Machine Learning-Based Pre-Impact Fall Detection Model to Discriminate Various Types of Fall.

Pre-impact fall detection can send alarm service faster to reduce long-lie conditions and decrease the risk of hospitalization. Detecting various types of fall to determine the impact site or direction prior to impact is important because it increases the chance of decreasing the incidence or severity of fall-related injuries. In this study, a robust pre-impact fall detection model was developed to classify various activities and falls as multiclass and its performance was compared with the performance of previous developed models. Twelve healthy subjects participated in this study. All subjects were asked to place an inertial measuring unit module by fixing on a belt near the left iliac crest to collect accelerometer data for each activity. Our novel proposed model consists of feature calculation and infinite latent feature selection (ILFS) algorithm, auto labeling of activities, and application of machine learning classifiers for discrete and continuous time series data. Nine machine-learning classifiers were applied to detect falls prior to impact and derive final detection results by sorting the classifier. Our model showed the highest classification accuracy. Results for the proposed model that could classify as multiclass showed significantly higher average classification accuracy of 99.57 ± 0.01% for discrete data-based classifiers and 99.84 ± 0.02% for continuous time series-based classifiers than previous models (p < 0.01). In the future, multiclass pre-impact fall detection models can be applied to fall protector devices by detecting various activities for sending alerts or immediate feedback reactions to prevent falls.

Socioeconomic and sociodemographic factors related to allergic diseases in Korean adolescents based on the Seventh Korea Youth Risk Behavior Web-based Survey: a cross-sectional study.

BACKGROUND: Various international reports have shown that socioeconomic and sociodemographic variables are correlated with allergic diseases; however, little is known about how these variables affect Korean adolescents. This study was conducted to identify socioeconomic and sociodemographic risk factors for allergic diseases in Korean adolescents to provide information for preventing and managing such conditions. METHODS: Data from the 2011 Korea Youth Risk Behavior Web-based Survey (KYRBWS-VII) of 75,643 adolescents were used. An anonymously administered online survey was conducted to collect dependent variable information on perceived sexes, residence, family affluence (Family Affluence Scale; FAS), parental education levels, subjective academic achievement, obesity, drinking and smoking. The independent variables were asthma, allergic rhinitis and atopic dermatitis. Multivariate logistic regression was used to analyze the correlations between the dependent and independent variables. RESULTS: Low subjective academic achievement, obesity, drinking and smoking were risk factors for asthma. High FAS, parental bachelor's degree and high subjective academic achievement were risk factors for allergic rhinitis. Finally, high FAS, maternal bachelor's degree and high subjective academic achievement were risk factors for atopic dermatitis. CONCLUSION: We found that high socioeconomic status (SES) was a risk factor for allergic diseases in Korean adolescents. We propose that the greater access to medical services and immunization (e.g., hygiene hypothesis) afforded by high SES influenced the prevalence of allergic diseases. Thus, as the Korean economy develops further, the prevalence of allergic diseases is likely to increase. Controlling harmful behavioral risk factors, such as drinking and smoking, may help to prevent adolescent allergic diseases.

Percentile Distributions of Birth Weight according to Gestational Ages in Korea (2010-2012).

The Pediatric Growth Chart (2007) is used as a standard reference to evaluate weight and height percentiles of Korean children and adolescents. Although several previous studies provided a useful reference range of newborn birth weight (BW) by gestational age (GA), the BW reference analyzed by sex and plurality is not currently available. Therefore, we aimed to establish a national reference range of neonatal BW percentiles considering GA, sex, and plurality of newborns in Korea. The raw data of all newborns (470,171 in 2010, 471,265 in 2011, and 484,550 in 2012) were analyzed. Using the Korean Statistical Information Service data (2010-2012), smoothed percentile curves (3(rd)-97(th)) by GA were created using the lambda-mu-sigma method after exclusion and the data were distinguished by all live births, singleton births, and multiple births. In the entire cohort, male newborns were heavier than female newborns and singletons were heavier than twins. As GA increased, the difference in BW between singleton and multiples increased. Compared to the previous data published 10 years ago in Korea, the BW of newborns 22-23 gestational weeks old was increased, whereas that of others was smaller. Other countries' data were also compared and showed differences in BW of both singleton and multiple newborns. We expect this updated data to be utilized as a reference to improve clinical assessments of newborn growth.

A retrospective analysis of conception per embryo transfer in dairy cattle in South Korea.

The bovine embryo production industry has seen significant growth over the past two decades, particularly in the production of in vitro produced embryos. This growth, driven by advancements in cryopreservation, in vitro culture mediums, ovum pick-up (OPU) procedures, ultrasonography devices, and embryo transfer (ET) has been notable. Particularly, ET is crucial for disseminating high genetic merit and amplifying foreign breeds by importing frozen embryos. This retrospective study aimed to assess factors affecting conception per embryo transfer (CPET) in Holstein-Friesian cattle in South Korea from October 2008 to July 2022. We evaluated type of embryo breed, type of embryo production (fresh and frozen; in vitro and in vivo production), recipient conditions including estrus type, corpus luteum quality, parity (nulliparous heifers, primiparous, and multiparous cows), and the daily mean temperature-humidity index (THI) as an index for heat stress. Type of embryo breed and estrus had no significant impact on CPET. However, we observed higher CPET in recipients with good quality corpus luteum, nulliparous heifers, and surrogates receiving fresh in vitro and frozen in vivo embryos. Importantly, CPET was not adversely affected by mild heat stress conditions (up to daily mean THI 76), indicating that using frozen in vivo embryos produced by multiple ovulation embryo transfer and fresh in vitro embryos by OPU-ET can help alleviate the subfertility issues in dairy cattle caused by global warming in Korea.

Annual Change in Fungal Concentrations and Allergic Sensitization Rates to Alternaria and Cladosporium in Korea During the Period 1998-2022.

PURPOSE: Atmospheric fungi are associated with respiratory allergies in humans, and some fungal spores can cause allergic diseases. Environmental and biological factors influence the concentrations of atmospheric spores. In this study, we evaluated the climate change-induced annual variations in fungal spore concentrations and allergic sensitization rates in the Seoul Metropolitan Area over a period of 25 years. METHODS: Fungal spores and pollen were obtained from Hanyang University Seoul and Guri Hospitals; they were identified and counted for 25 years (1998-2022). The study participants included patients who underwent tests for allergic diseases in both hospitals. Their allergenic sensitization rates were determined via allergic skin prick and serum tests, after which their sensitization rates to allergenic fungi and pollens were calculated. The daily climatic variables were obtained from the Korea Meteorological Administration. RESULTS: The total annual atmospheric fungal concentrations decreased in both areas during the period. Simultaneously, we recruited 21,394 patients with allergies (asthma, 1,550; allergic rhinitis, 5,983; and atopic dermatitis, 5,422) from Seoul and Guri Hospitals for allergenic fungal sensitization evaluations over the period. The allergenic fungal sensitization rates decreased annually in both areas over that time `+(Alternaria [3.5%] and Cladosporium [4.4%] in 1998; Alternaria [0.2%] and Cladosporium [0.2%] in 2022). In contrast, the annual pollen concentrations increased with the sensitization rates to pollen in children. CONCLUSIONS: The atmospheric fungal concentrations decreased annually, with allergic sensitization rate decreasing over the period of 25 years. Allergenic fungal sporulation could decrease with climate changes, such as desertification and drought. Extended monitoring periods and further large-scale studies are required to confirm the causality and to evaluate the impact of climate change.

Work-related injuries and fatalities among farmers in South Korea.

BACKGROUND: Agricultural injuries are increasing in South Korea according to its workforce's reduced size and increased age. Available data are insufficient to exactly understand present situation. This study evaluated the patterns and characteristics of agricultural injury and assessed the injury rates. METHODS: We analyzed the entry and compensation data compiled in 2005 by the Safety Aid System of Farm Workers, South Korea's government insurance for agricultural injury. We examined the general characteristics, rates, and mortality of agricultural injury. RESULTS: There were 11,931 compensated events, including 219 compensated deaths. Farm injuries occurred most frequently in October, and most injuries were unintentional. The incidence and fatality rates were 16.67 per 1,000 person-years and 30.59 per 100,000 person-years, respectively. Most number of agricultural injuries occurred in October. The most common cause of deaths was accidents caused by machinery use (35.64%) for males and other transport accidents (23.53%) for females, while the most common cause of injuries for females was falls (45.39%). Incidence and mortality rate of agricultural injuries were higher in elders. CONCLUSIONS: Although injury rates may have been underestimated owing to data limitations, we are confident that South Korea's rate is higher than those seen in other countries or occupations.

Indicators Related to Cardiopulmonary Resuscitation According to Occupation Among Family Members of Coronary Heart Disease Patients.

This study aimed to evaluate differences in cardiopulmonary resuscitation (CPR)-related indicators among families of community-dwelling coronary heart disease (CHD) patients according to their occupation. A total of 6,867 family members living with CHD patients were selected for analysis from the 2016 Korea Community Health Survey. Respondents' occupations were classified into managers and professionals (MP), clerks (CL), service and sales workers (SSW), agricultural/forestry/fishery workers (AFFW), mechanical and manual laborers (MML), and homemakers and unemployed (HU). The adjusted odds ratio (aOR) for awareness of CPR in the MP (3.82), SSW (1.73), and MML (1.29) groups were higher than that in HU (reference), while the CL (1.42) and AFFW (1.04) groups showed no significant difference compared to HU. The aORs for experience with CPR education and manikin-assisted CPR training were higher among the MP (4.00 and 3.94), CL (2.61 and 2.26), SSW (2.02 and 1.91), and MML (1.99 and 1.69) groups than in HU, and only AFFW (1.22 and 1.18) showed no difference from HU. Finally, the aOR for self-efficacy in CPR performance was significantly higher among the MP (3.17), CL (1.64), SSW (1.87), and MML (1.44) groups than in HU. However, there was no significant difference between AFFW (1.22) and HU in self-efficacy in CPR performance. To improve the survival rate of CHD patients through successful CPR at the pre-hospital stage during cardiac arrest, it is important to increase the ability of family members of CHD patients to perform CPR, especially among those in AFFW and HU occupations.

Evaluation of Short-Term Exposure Levels on Ammonia and Hydrogen Sulfide During Manure-Handling Processes at Livestock Farms.

BACKGROUND: Ammonia and hydrogen sulfide are harmful gases generated during aerobic/anaerobic bacterial decomposition of livestock manure. We evaluated ammonia and hydrogen sulfide concentrations generated from workplaces at livestock farms and determined environmental factors influencing the gas concentrations. METHODS: Five commercial swine farms and five poultry farms were selected for monitoring. Real-time monitors were used to measure the ammonia and hydrogen sulfide concentrations and environmental conditions during the manure-handling processes. Monitoring was conducted in the manure storage facility and composting facility. Information on the farm conditions was also collected through interview and walk-through survey. RESULTS: The ammonia concentrations were significantly higher at the swine composting facilities (9.5-43.2 ppm) than at other manure-handling facilities at the swine and poultry farms, and high concentrations of hydrogen sulfide were identified during the manure agitation and mixing process at the swine manure storage facilities (6.9-19.5 ppm). At the poultry manure-handling facilities, the ammonia concentration was higher during the manure-handling processes (2.6-57.9 ppm), and very low hydrogen sulfide concentrations (0-3.4 ppm) were detected. The air temperature and relative humidity, volume of the facility, duration of manure storage, and the number of animals influenced the gas concentrations. CONCLUSION: A high level of hazardous gases was generated during manure handling, and some levels increased up to risk levels that can threaten workers' health and safety. Some of the farm operational factors were also found to influence the gas levels. By controlling and improving these factors, it would be possible to protect workers' safety and health from occupational risks.

Increased risk of atherosclerosis associated with pesticide exposure in rural areas in Korea.

Atherosclerosis is a progressive inflammation in systemic vessels, and pesticide exposure has been emerging as its risk factor. This cross-sectional study investigated the association between pesticide exposure and the risk of atherosclerosis in a rural population in Korea using carotid intima-media thickness (CIMT). This study used dataset from the baseline survey of the Korea Farmers Cohort Study between November 2005 and January 2008, and the final analysis included 477 participants. Well-structured questionnaires were used to estimate pesticide exposure. CIMT ≥ 0.9 mm was established for carotid atherosclerosis. Multiple logistic regression analyses were undertaken to evaluate the association between pesticide exposure and atherosclerosis, adjusting demographic and health-related confounders. Even after adjustments, the increased risk of atherosclerosis was significantly associated with pesticide exposure, such as a lifetime history of farming (odds ratio [OR] 3.25 95% confidence interval [CI] 1.51-6.98), a history of using pesticide (OR 3.42 95% CI 1.63-7.16), using pesticide 10 times or more annually (OR 2.55 95% CI 1.21-5.39), and higher cumulative exposure index level (OR 3.63 95% CI 1.65-7.97). Further prospective studies are required to elucidate effects of pesticide exposure on the risk of atherosclerosis.

Comparison between urban and rural mortality in patients with acute myocardial infarction: a nationwide longitudinal cohort study in South Korea.

OBJECTIVES: This study investigated the risk associated with interhospital transfer of patients with acute myocardial infarction (AMI) and clinical outcomes according to the location of the patient' residence. DESIGN: A nationwide longitudinal cohort. SETTING: National Health Insurance Service database of South Korea. PARTICIPANTS: This study included 69 899 patients with AMI who visited an emergency centre from 2013 to 2015, as per the Korea National Health Insurance Service database. PRIMARY OUTCOME MEASURE: The clinical outcome of a patient with AMI was defined as mortality within 7 days, 30 days and 1 year. RESULTS: Clinical outcomes were analysed and compared with respect to the location of the patient's residence and occurrence of interhospital transfer. We concluded that the HR of mortality within 7 days was 1.49 times higher (95% CI 1.18 to 1.87) in rural patients than in urban patients not subjected to interhospital transfer and 1.90 times higher (95% CI 1.13 to 3.19) in transferred rural patients than in non-transferred urban patients. CONCLUSIONS: To reduce health inequality in rural areas, a healthcare policy considering regional characteristics, rather than a central government-led, catch-all approach to healthcare policy, must be formulated. Additionally, a local medical emergency delivery system, based on allocation of roles between different medical facilities in the region, must be established.

Hearing impairment among Korean farmers, based on a 3-year audiometry examination.

INTRODUCTION AND OBJECTIVE: Work noise exposure among farmers can cause hearing loss. Farmers are exposed to hazardous noise from equipment and domestic animals, and experience high rates of noise-induced hearing loss. The aim of our study was to evaluate the hearing thresholds of farmers in Korea. This study is the first to evaluate hearing impairment in Korean farmers nationwide. There have been few studies that have performed audiometric testing to measure hearing impairment at the national level in Korea. MATERIAL AND METHODS: Through the Farm Work Safety Model Project among the 40 villages in which inhabitants received health check-ups from 2006-2008, 2,027 people from 35 villages were targeted (957 people in 16 villages in 2006, 436 people in five villages in 2007, and 634 people in 14 villages in 2008) and underwent pure tone audiometry tests. 2,027 people from 35 villages underwent pure tone audiometry tests through the Farm Work Safety Model Project. The tests were conducted using a portable audiometer, and air conduction thresholds were determined. RESULTS: Hearing impairment at 3kHz and above was more prevalent in men than in women. The prevalence of moderate-to-profound hearing impairment was 19.6% in the total study population and increased with age. CONCLUSIONS: It is proposed that the high prevalence rate of farmers' hearing impairment may be due to excessive workplace noise. To manage farmers' hearing health, precise evaluations of farmers' hearing acuity and noise exposure on farms should be conducted. This study might be a stepping-stone to protect farmers' hearing health.

Differences in the awareness of stroke symptoms and emergency response by occupation in the Korean general population.

We evaluated the difference in awareness of stroke warning signs (SWS) and emergency response among occupational groups in the community-dwelling population. From the 2016 Korea Community Health Survey, a total of 10,445 individuals without stroke were included in the analysis. Multiple logistic regression analysis was used to explore the association of occupation with awareness of SWS and correct emergency response. SWS included the following: sudden numbness or weakness, sudden difficulty speaking or understanding speech, sudden dizziness, sudden visual impairment, and sudden severe headache. Respondents' occupation was classified into six groups: managers and professionals (MP); clerks; service and sales workers (SSW); agricultural, forestry, and fishery workers (AFFW); mechanical and manual laborers (MML); or housewives and unemployed people (HUP). Awareness of each SWS was the same with the highest for MP and lowest for AFFW. After adjusting for socio-demographic factors, compared to MP (reference), AFFW (odds ratio 0.49; 95% confidence interval 0.36-0.67), HUP (0.55; 0.40-0.75), MML (0.57; 0.42-0.79), and SSW (0.62; 0.45-0.86) had significantly lower ORs for knowing at least one of the SWS. Additionally, AFFW (0.79; 0.66-0.96) and MML (0.76; 0.63-0.91) had significantly lower ORs for knowing all five SWS compared to MP. However, there was no significant occupational difference in correct emergency response when a stroke occurred. To improve stroke literacy and to reduce the disparity of awareness of SWS in community settings, public health efforts with an emphasis on AFFW and MML are needed.

Association Between Chronic Exposure to Pesticide and Suicide.

OBJECTIVE: We investigated the association between suicide and pesticide exposure in a community-based cohort study. METHODS: We performed a longitudinal analysis of 6333 who participated in the initial survey of the Korean Genome and Epidemiology Study. Data were collected using a questionnaire to assess the prevalence of suicide. We calculated the hazard ratios (HRs) for suicide by pesticide exposure using the Cox proportional hazard model. RESULTS: After adjusting for variables, participants exposed to pesticides had a 1.88-fold increased risk of suicide (HR, 1.88; 95% confidence interval [CI], 1.11 to 3.16) than those who were not exposed. Study populations with greater pesticide use (HR, 2.42; 95% CI, 1.27 to 4.60) and pesticide addiction had the highest suicide rates (HR, 1.91; 95% CI, 1.03 to 3.56). CONCLUSIONS: Pesticide exposure for suicide should be considered during the development and implementation of suicide prevention in rural area.

Exposure to pesticides and the prevalence of diabetes in a rural population in Korea.

BACKGROUND: Among the adverse health effects of exposure to pesticides, an association with diabetes has been reported. However, there is a lack of epidemiologic studies on the health effects of exposure to pesticides, particularly investigating the association between occupational pesticide exposure and diabetes prevalence. PURPOSE: The present study examined the association between pesticide exposure and prevalence of diabetes in a rural population in Korea. METHODS: This cross-sectional study used data from the Korea Farmers Cohort study, and included 2559 participants in the baseline survey between November 2005 and January 2008. We performed a clinical examination including blood sampling and assessed data on diabetes diagnosis, demographics, and pesticide exposure. Logistic regression was performed to evaluate the association between pesticide exposure and diabetes prevalence, adjusting for age, sex, monthly income, and marital status. In addition, a stratified analysis by body mass index (BMI) was conducted, with two categories: normal weight (<25 kg/m2) and overweight or obese (≥25 kg/m2). RESULTS: At baseline, the prevalence of diabetes was 9.30%. Pesticide exposure was associated with the risk of diabetes after adjustment for covariates. In the analysis stratified by BMI, all the variables related to pesticide exposure were associated with prevalence of diabetes in the overweight or obese group, whereas no significant association was found in the normal weight group. CONCLUSION: Exposure to pesticides was associated with diabetes, and this association was stronger in overweight or obese individuals than in normal weight individuals. Further longitudinal studies that consider information on BMI are necessary.

Analysis of checklists for agricultural safety management.

INTRODUCTION: The current health and safety management system under the Occupational Health and Safety Act has avoided agriculture in Korea. It is important to consider the various safety systems used in agricultural health and safety to develop effective regulations. OBJECTIVE: The aims were to classify and review the items from various checklists using safety systems, such as design, training, etc., ultimately aimed at proposing directions for improving the health and safety of farmers. MATERIAL AND METHODS: Among the retrieved checklists with Google, four were chosen for this study, based on criteria such as the Checklist developed by an international organization, as well as others. Each item on the checklist was categorized using criteria concerning safety systems, developed based on previous studies. RESULTS: The total number of analyzed items was 573, which is 36 more than the actual number of checklist items (537). The proportion of items belonging to the training/procedures system was the highest (32.5%); the second-highest was for the mitigation system - 18.2%.; the third-largest proportion of items was maintenance/inspection - with 14.3%. Items related to the design and human factor systems were 8.2% and 5.6%, respectively. The safety system with the lowest proportion was the warning/notification system - 4.2% of the total items. The proportion of items that could not be classified into safety systems was found to be 16.1%. CONCLUSIONS: A large number of items belonging to the training/procedures system reported as occasionally not effective in prevention of injury were found in the checklists. It appears important to develop checklist items proposing the supplementation of various safety systems, rather than presenting items that are biased towards certain safety systems.

Comparisons of ergonomic evaluation tools (ALLA, RULA, REBA and OWAS) for farm work.

INTRODUCTION: The purpose of this study was to validate the agricultural lower limb assessment (ALLA) ergonomic checklist, which was developed for various agricultural tasks in Korea. METHODS: One hundred and ninety-six working postures were selected from the real agricultural tasks to verify ALLA, a lower limb body posture assessment tool, and then evaluated by 16 ergonomic experts. Hit rate, quadratic weighted κ, one-way analysis of variance and t-test analyses were applied to compare ALLA with other assessment tools. RESULTS: ALLA analysis had a superior hit rate with ergonomic expert assessment compared with other assessment tools. Quadratic weighted κ analysis also showed that ALLA provided superior estimates of risk levels for farm working postures. DISCUSSION: ALLA would be an appropriate assessment tool to estimate risk factors for various lower limb body postures which frequently occur in agricultural tasks in Korea. ALLA is a simple and accurate risk assessment tool that could be usefully applied to identify and mitigate risk factors and work-related musculoskeletal disorders in agricultural tasks, and also to evaluate the effects of control and intervention for working conditions.

A Longitudinal Study on the Effects of Negative Rearing Experiences on Adolescents' Social Withdrawal and Aggression.

BACKGROUND: Children who have experienced negative rearing behaviors show a lack of self-confidence due to emotional instability and are reserved in interpersonal relationships. This can lead to failure in social adaptation and a high risk of depression, suicide, criminal acts, and anti-social behaviors. Therefore, this study aims to analyze the effects of experiencing negative parental rearing behaviors, such as neglect and abuse, on adolescents' social withdrawal and aggression, by utilizing multivariate latent growth models. METHODS: Data from the Korean Children and Youth Panel Study (KCYPS), a survey conducted by the National Youth Policy Institute targeting a cohort of three different age groups (grade 1, grade 4, and grade 7), from 2010 to 2016 was used. Multi-stage stratified sampling methods were used in the KCYPS, which surveyed the students and parents of the selected grade levels. This study analyzed the data for grade 7, from second year (grade 8) to fourth year (grade 10). RESULTS: Negative rearing experiences had a significant effect on social withdrawal and aggression, and this influence was shown to persist over the long term. CONCLUSION: This study examined the long-term developmental trajectory in the relationship between risk factors for adolescent development. Furthermore, the relationship between risk factors was shown to have not only short term but long-term effects as well, which reinforces the limitations of previous studies.

Pesticide metabolite and oxidative stress in male farmers exposed to pesticide.

BACKGROUND: The objective of this study was to measure malondialdehyde (MDA) and isoprostane which has been used as an index of lipid injury, 8-hydroxy-2'-deoxyguanosine (8-OHdG), which has been used as an index of DNA damage, and dialkyl-phosphate (DAP), which has been used to quantify pesticide exposure, and to investigate the relationship between pesticide exposure and oxidative stress. METHODS: This study was a cross-sectional study that evaluated 84 male farmers exposure to pesticide. In this study, 8-OHdG, isoprostane, and MDA were measured as oxidative stress indices, and dialkyl-phosphate (dimethylphosphate(DMP), diethylphosphate(DEP), dimethylthiophosphate(DMTP), and diethylthiophosphate (DETP)) excreted in the urine was also measured to evaluate pesticide exposure. A linear regression analysis was performed to investigate the relationship between pesticide metabolites, and oxidative stress biomarkers. RESULTS: A Correlation analysis was performed for pesticide exposure month (PEI), cumulative exposure index (CEI), and DAP as well as the concentration of the oxidative stress biomarkers. The PEM significantly and positively correlated to the levels of 8-OHdG, isoprostane, CEI, and DMP. CEI showed a correlation to 8-OHdG and PEM. DMP, DEP, and DETP showed a positive correlation to 8-OHdG, isoprostane, and MDA. A correlation analysis was adjusted some demographic characteristics, such as age, smoking, drinking, and exercise to determine the relationship between pesticide exposure and oxidative stress. The 8-OHdG, isoprostane, and MDA levels were significantly related to the DMP (ß = 0.320), DEP (ß = 0.390), and DETP (ß = 0.082); DMP (ß = 0.396), DEP (ß = 0.508), and DETP (ß = 0.504); and DMP (ß = 0.432), DEP (ß = 0.508), and DETP (ß = 0.329) levels, respectively. CONCLUSIONS: The concentration between oxidative stress biomarkers and the pesticide metabolite were a positive correlation. Indicators of oxidative stress was associated with a pesticide metabolite DMP, DEP, and DETP. Therefore, Pesticide exposure and oxidative stress were relevant.

Exposure to pesticide as a risk factor for depression: A population-based longitudinal study in Korea.

BACKGROUND: Exposure to pesticides is associated with mental disorders, including depression, especially among occupationally exposed populations, such as farmers. The results of experimental studies ascribed the negative effects of pesticides on mental health to their neurotoxic and endocrine-disrupting activities. PURPOSE: This study aimed to investigate the association between the risk of depression and high- or low-level exposure to pesticides in a rural population. METHODS: This longitudinal study was performed in 2005-2008 (baseline) and 2008-2012 (follow-up) to evaluate the risk of depression among 2151 Korean adults. A standardized questionnaire was used to obtain information on depression upon self-reported exposure to pesticide based on the Center for Epidemiologic Studies Depression Scale. Logistic regression analysis was performed to evaluate the association between pesticide exposure and depression. We adjusted the data for age, cigarette smoking status, current alcohol use, monthly income, educational level, marriage status, and religion. RESULTS: Among the individuals who reported depression, the number of participants who used pesticides was significantly higher than that who did not (N=61 [7.2%] vs. N=54 [4.2%], P=0.003). A positive association was noted between >20-year period of pesticide use and depression (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.41-3.88). Individuals who reported depression showed greater odds of being exposed to higher pesticide concentrations (OR, 2.33; 95% CI, 1.40-3.88) and experiencing pesticide poisoning (OR, 5.83; 95% CI, 1.80-18.86) than those who did not. CONCLUSION: Exposure to pesticides at a high concentration was found to be associated with depressive symptoms among Korean adults.

Transactivation of EGFR mediates insulin-stimulated ERK1/2 activation and enhanced cell migration in human corneal epithelial cells.

PURPOSE: Insulin activates phosphatidylinositol 3-kinase (PI3K) and extracellular signal-regulated kinase (ERK)-1/2 in human corneal epithelial cells. These events have been shown to be involved in wound healing. However, the mechanism of insulin-induced ERK pathway is not clear during corneal wound healing. In this study, the effect of insulin associated with epidermal growth factor receptor (EGFR) on wound healing in transformed human corneal epithelial cells was investigated to determine the signaling mechanism involved. METHODS: SV40-immortalized human corneal epithelial (THCE) cells were cultured on a diluted Matrigel matrix that resembled the basement membrane of the corneal epithelium. A wound was introduced with a micropipette tip, and closure of the scratch wound was photographed 12 h after exposure to insulin. Activation of EGFR was analyzed by immunoprecipitation, and cytoskeletal rearrangements were visualized with rhodamine-conjugated phalloidin. RESULTS: Exposure of corneal epithelial cells to insulin induced phosphorylation of EGFR. Inhibition of EGFR activation by AG1478 or the MMP inhibitor, GM6001, reduced phosphorylation of insulin-induced ERK in the presence of insulin and delayed wound closure. In addition, cells exposed to insulin contained stress fibers and their submembranous cortical actin was depleted. These effects were inhibited by AG1478. CONCLUSIONS: Inhibition of EGFR activity decreases cell migration involved in insulin-induced wound repair, an effect that mimics inhibition of MMP activation. Inhibition of MMP activity leads to decreased EGFR phosphorylation. Our data show that insulin stimulates wound healing in the corneal epithelium by activating EGFR, and point to a novel insulin signaling pathway that acts during corneal wound healing.