Safety Assessment of Starch Nanoparticles as an Emulsifier in Human Skin Cells, 3D Cultured Artificial Skin, and Human Skin.

Emulsion systems are widely used in various industries, including the cosmetic, pharmaceutical, and food industries, because they require emulsifiers to stabilize the inherently unstable contact between oil and water. Although emulsifiers are included in many products, excessive use of emulsifiers destroys skin barriers and causes contact dermatitis. Accordingly, the consumer demand for cosmetic products made from natural ingredients with biocompatibility and biodegradability has increased. Starch in the form of solid nanosized particles is considered an attractive emulsifier that forms and stabilizes Pickering emulsion. Chemical modification of nanosized starch via acid hydrolysis can effectively provide higher emulsion stability. However, typical acid hydrolysis limits the industrial application of starch due to its high time consumption and low recovery. In previous studies, the effects of starch nanoparticles (SNPs) prepared by treatment with acidic dry heat, which overcomes these limitations, on the formation and stability of Pickering emulsions were reported. In this study, we evaluated the safety of SNPs in skin cell lines, 3D cultured skin, and human skin. We found that the cytotoxicity of SNPs in both HaCaT cells and HDF cells could be controlled by neutralization. We also observed that SNPs did not induce structural abnormalities on 3D cultured skin and did not permeate across micropig skin tissue or human skin membranes. Furthermore, patches loaded with SNPs were found to belong in the "No irritation" category because they did not cause any irritation when placed on human skin. Overall, the study results suggest that SNPs can be used as a safe emulsifier in various industries, including in cosmetics.

A direct contact bioassay using sulfur-oxidizing bacteria (SOB) for toxicity assessment of contaminated field soils.

In this study, 11 low/uncontaminated (including Lufa 2.2) and 9 contaminated field soils with varying geophysical and physicochemical characteristics were evaluated for toxicities based on oxygen consumption of sulfur-oxidizing bacteria (SOB). Oxygen consumption of the low/uncontaminated soils ranged between 7.9 mL and 9.5 mL, while contaminated soils ranged between 0.4 mL and 5.4 mL. Inherent test variability (CVi), variation due to soil natural properties (CVns) and minimal detectable difference (MDD) values ranged 1.2%-3.9%, 3.5%-16.9%, and 2.1%-4.3%, respectively. The toxicity threshold of 20% was established for soil toxicity based maximal tolerable inhibition (MTI). All the contaminated soils were found to be toxic and showed inhibition between 42% and 100% above the 20% threshold value. Increased proportions of clay and slit enhanced the of inhibitory effect of contaminants on SOB by reducing the oxygen consumption. Current study provides a suitable method for the rapid toxicity assessment of contaminated field soils with the advantages of ease of handling and rapidity without employing elutriates and sophisticated equipments and tools.

Sociodemographic factors associated with the use of mental health services in depressed adults: results from the Korea National Health and Nutrition Examination Survey (KNHANES).

BACKGROUND: The aims of this study were to determine the utilization of mental health services (MHSs) by adults with a depressive mood and to identify the influencing sociodemographic factors, using a nationwide representative Korean sample. METHODS: The study included 2735 subjects, aged 19 years or older, who had experienced a depressive mood continuously for over 2 weeks within the previous year, using the data from the KNHANES IV (Fourth Korea National Health and Nutrition Examination Survey), which was performed between 2007 and 2009, and involved a nationally representative sample of the Korean community population who were visited at home. A multivariate logistic regression analysis was used to estimate the adjusted odd ratios (ORs) and 95% confidence intervals (CIs) for the use of MHSs, which was defined as using healthcare institutions, consulting services, and inpatient or outpatient treatments due to mental health problems. RESULTS: MHSs had been used by 9.6% of the subjects with a depressive mood. The use of the MHSs was significantly associated with age, education level, and employment status, after adjusting for sociodemographic and health-related factors. Specifically, the OR for the nonuse of MHSs by the elderly (≥65 years) relative to subjects aged 19-34 years was 2.55 (95% CI = 1.13-5.76), subjects with a lower education level were less likely to use MHSs compared to those with a higher education level (7-9 years, OR = 2.35, 95% CI = 1.19-4.64; 10-12 years, OR = 1.66, 95% CI = 1.07-2.56; ≥13 years, reference), and the OR of unemployed relative to employed was 0.47 (95% CI = 0.32-0.67). CONCLUSIONS: Among Korean adults with a depressive mood, the elderly, those with a lower education level, and the employed are less likely to use MHSs. These findings suggest that mental health policies should be made based on the characteristics of the population in order to reduce untreated patients with depression. Greater resources and attention to identifying and treating depression in older, less educated, and employed adults are warranted.

Gender differences in emergency stroke care and hospital outcome in acute ischemic stroke: a multicenter observational study.

BACKGROUND: We aimed to investigate the effect of gender difference on the accessibility to emergency care, hospital mortality and disability in acute stroke care. METHODS: This study was performed on a single-tiered basic emergency medical service with a comprehensive national health insurance. Demographic variables, risk factors, elapsed time intervals, performing diagnosis and treatment options, hospital mortality, and modified Rankin Scale of acute ischemic stroke during 2008 were collected. We modeled the multivariate regression analysis for gender differences on the accessibility, hospital mortality, and disability. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated adjusting for potential risk factors. RESULTS: The total number of patients was 6635. The time from symptom onset to emergency department (ED) arrival and to computed tomography or magnetic resonance imaging scan and from ED arrival to computed tomography or magnetic resonance imaging scan was significantly longer in women. No significant difference was found in either the time to intravenous thrombolysis or in the number of patients who received intravenous thrombolysis, anti-platelet therapy, anti-coagulation, or operation. The hospital mortality rate was higher in women (3.9%) than in men (2.9%) (P = .03). The increased disability was significantly higher in women (67.8%) than in men (65.1%) (P = .02). The hospital mortality and increased disability showed a non-significant difference between the 2 genders in the adjusted model (OR, 1.10; 95% CI, 0.74-1.64) and (OR, 1.11; 95% CI, 0.96-1.28), respectively. CONCLUSION: The adjusted model for risk factors showed no significant difference on hospital mortality and disability between the 2 genders for stroke patients.

[The effects of the parents' social class on infant and child death among 1995-2004 birth cohort in Korea].

OBJECTIVES: To investigate the effect of parents' social class on infant and child mortality rates among the birth cohort, for the period of transition to and from the Koran economic crisis 1995-2004. METHODS: All births reported to between 1995 and 2004 (n=5,711,337) were analyzed using a Cox regression model, to study the role of the social determinants of parents in infant and child mortality. The results were adjusted for the parents' age, education and occupation, together with mother's obstetrical history. RESULTS: The crude death rate among those under 10 was 3.71 per 1000 births (21,217 deaths among 5,711,337 births) between 1995 and 2004. The birth cohorts from lower educated parents less than elementary school showed higher mortality rates compared with those from higher educated parents over university level (HR:3.0 (95% CI:2.8-3.7) for father and HR:3.4 (95% CI:3.3-4.5) for mother). The mother's education level showed a stronger relationship with mortality among the birth cohort than that of the fathers'. The gaps in infant mortality rates by parents' social class, and educational level became wider from 1995 to 2004. In particular, the breadth of the existing gap between higher and lower parents' social class groups has dramatically widened since the economic crisis of 1998. DISCUSSIONS: This study shows that social differences exist in infant and child mortality rates. Also, the gap for the infant mortality due to social class has become wider since the economic crisis of 1998.