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Background/Aim: Inhalation toxicity tests of glycolic acid, which is used in many household products, have been reported, but the pulmonary toxicity of glycolic acid has not been confirmed. Here, the lung damage caused by glycolic acid was investigated in rats. Materials and Methods: An intratracheal instillation test was performed with glycolic acid in male rats. Bronchoalveolar lavage fluid (BALF) and histopathological analysis were conducted to identify the pulmonary toxicities. Results: Intratracheal instillation of glycolic acid caused weight loss in animals and increased the content of lactate dehydrogenase, total protein, polymorphonuclear neutrophils, and inflammatory cytokines in BALF. In addition, pulmonary edema, alveolar/interstitial inflammation, and necrosis and desquamation of bronchial/bronchiolar epithelia were confirmed via histopathological examination. Conclusion: Exposure to glycolic acid can be harmful and toxic to the lungs.

The purpose of this article is to discuss the current status of research mentoring in nursing across 4 countries (the United States, Taiwan, South Korea, and Japan) and to make suggestions for future research mentoring. Seven leaders reflected on the current status of research mentoring in nursing, provided exemplars/cases from their own experiences, and their reviews of the literature. Six themes were discussed: (a) "culturally defined"; (b) "professionally contextualized"; (c) "teaching research integrity and research practice"; (d) "with mutual respect and care"; (e) "based on effective communication"; and (f) "supported by institutional and governmental commitment and infrastructure."

In patients with intraoperative massive bleeding, the effects of fluid and blood volume on postoperative pulmonary edema are uncertain. Patients with intraoperative massive bleeding who had undergone a non-cardiac surgery in five hospitals were enrolled in this study. We evaluated the association of postoperative pulmonary edema risk and intra- and post-operatively administered fluid and blood volumes in patients with intraoperative massive bleeding. In total, 2090 patients were included in the postoperative pulmonary edema analysis, and 300 patients developed pulmonary edema within 72 h of the surgery. The postoperative pulmonary edema with hypoxemia analysis included 1660 patients, and the condition occurred in 161 patients. An increase in the amount of red blood cells transfused per hour after surgery increased the risk of pulmonary edema (hazard ratio: 1.03, 95% confidence interval: 1.01–1.05) p = 0.013) and the risk of pulmonary edema with hypoxemia (hazard ratio: 1.04, 95% confidence interval: 1.01–1.07, p = 0.024). An increase in the red blood cells transfused per hour after surgery increased the risk of developing pulmonary edema. This increase can be considered as a risk factor for pulmonary edema.

Ambient particulate matter 2.5 (PM2.5) and total suspended particles (TSPs) are common airborne pollutants that cause respiratory and cardiovascular diseases. We investigated the differences of cytotoxicity and mechanism between PM2.5 and TSP activity in human alveolar epithelial A549 cells. Atmospheric samples from the central district of Seoul were collected and their chemical compositions were analyzed by inductively-coupled plasma mass spectrometry and ion chromatography. PM2.5 and TSP contained high concentrations of heavy metals (Cu, Fe, Zn, and Pb). The most abundant ions in PM2.5 were SO42−, NH4+, and NO3−. A549 cells were exposed to PM2.5 and TSP (25–200 µg/mL) for 24 h. TSP was more cytotoxic than PM2.5 per unit mass. PM2.5 induced oxidative stress, as evidenced by increased levels of a glutamate-cysteine ligase modifier, whereas low-concentration TSP increased hemeoxygenase-1 levels. PM2.5 and TSP did not affect c-Jun N-terminal kinase expression. The levels of nuclear factor erythroid 2-related factor 2 (Nrf2) in PM2.5- and TSP-treated cells decreased significantly in the cytosol and increased in the nucleus. Thus, Nrf2 may be a key transcription factor for detoxifying environmental airborne particles in A549 cells. TSP and PM2.5 could activate the protective Kelch-like ECH-associated protein 1/Nrf2 pathway in A549 cells.

Obesity is a critical target for public health interventions worldwide. There are many causes of obesity, and the importance of the gut microbiota in its pathogenesis has recently been recognized. The composition and function of the gut microbiota play a role in obesity and metabolic disease, yet the underlying mechanisms are unclear. Advances in our understanding of the link between obesity and the gut microbiota have suggested the potential of its manipulation for treating obesity. In this review, we summarize current knowledge of the interactions between the gut microbiota and obesity as well as the therapeutic potential of its modulation. (Korean J Med 2019;94:410-413)

인터넷 개인방송의 이용증가로 일부 개인방송 콘텐츠 문제가 사회문화적 쟁점이 되면서 인터넷 개인방송에 대한 규제 강화 목소리가 커지고 있다. 인터넷 공간에 대한 규제는 인터넷 공간이 가지는 "개방, 자유, 참여" 특성으로 인해 이에 대한 다른 입장이 나타나고 있다. 본 연구는 현재 국내 인터넷 개인방송 영역을 둘러싼 내·외부의 규제 현황을 확인하고자 하였다. 인터넷 개인방송 콘텐츠 심의기관, 동영상 플랫폼사업자, MCN 콘텐츠사업자 및 크리에이터를 대상으로 심층인터뷰를 진행하였고, 관련 자료를 바탕으로 인터넷 개인방송에 대한 규제 현황을 분석하였다. 분석 결과, 심의기관을 통한 인터넷 개인방송에 관한 내용규제는 사업자의 자율적 운영의 보완적 성격을 가지고 있었다. 플랫폼사업자들의 자율규제 현황은 사업자마다 운영정책과 대응 시스템이 다르게 나타났다. 이에 공동의 지침이나 동일한 수준의 규제 기준이 필요한 상황이다. 본 연구의 분석 결과를 바탕으로, 인터넷 개인방송의 합리적·효율적 자율규제 시스템을 위한 방안을 제시하였다.

Background Predicting difficult airway is challengeable in patients with limited airway evaluation. The aim of this study is to develop and validate a model that predicts difficult laryngoscopy by machine learning of neck circumference and thyromental height as predictors that can be used even for patients with limited airway evaluation. Methods Variables for prediction of difficulty laryngoscopy included age, sex, height, weight, body mass index, neck circumference, and thyromental distance. Difficult laryngoscopy was defined as Grade 3 and 4 by the Cormack-Lehane classification. The preanesthesia and anesthesia data of 1677 patients who had undergone general anesthesia at a single center were collected. The data set was randomly stratified into a training set (80%) and a test set (20%), with equal distribution of difficulty laryngoscopy. The training data sets were trained with five algorithms (logistic regression, multilayer perceptron, random forest, extreme gradient boosting, and light gradient boosting machine). The prediction models were validated through a test set. Results The model’s performance using random forest was best (area under receiver operating characteristic curve = 0.79 [95% confidence interval: 0.72–0.86], area under precision-recall curve = 0.32 [95% confidence interval: 0.27–0.37]). Conclusions Machine learning can predict difficult laryngoscopy through a combination of several predictors including neck circumference and thyromental height. The performance of the model can be improved with more data, a new variable and combination of models.

Recent research on in vitro systems has focused on mimicking the in vivo situation of cells within the respiratory system. However, few studies have predicted inhalation toxicity using conventional and simple submerged two-dimensional (2D) cell culture models. We investigated the conventional submerged 2-D cell culture model as a method for the prediction of acute inhalation toxicity. Median lethal concentration (LC50 ) (rat, inhalation, 4 h) and half maximal inhibitory concentration (IC50 ) (lung or bronchial cell, 24 h) data for 59 substances were obtained from the literature and by experiments. Cytotoxicity assays were performed on 44 substances with reported LC50 , but without IC50 , data to obtain the IC50 values. A weak correlation was observed between the IC50 and LC50 of all substances. Semi-volatile organic compounds (SVOCs) and non-VOCs (NVOCs) (16 substances) with a water solubility of ≥1 g/L were strongly correlated between 24-h IC50 and 4-h LC50 , and this had an excellent predictive ability to distinguish between Categories 1-3 and 4 (Globally Harmonized System classification for acute inhalation toxicity). Our results suggest that the submerged 2-D cell culture model may be used to predict in vivo acute inhalation toxicity for substances with a water solubility of ≥1 g/L in SVOCs and NVOCs.

Cetylpyridinium chloride (CPC), a quaternary ammonium compound and cationic surfactant, is used in personal hygiene products such as toothpaste, mouthwash, and nasal spray. Although public exposure to CPC is frequent, its pulmonary toxicity has yet to be fully characterized. Due to high risks of CPC inhalation, we aimed to comprehensively elucidate the in vitro and in vivo toxicity of CPC. The results demonstrated that CPC is highly cytotoxic against the A549 cells with a half-maximal inhibitory concentration (IC50 ) of 5.79 μg/ml. Following CPC exposure, via intratracheal instillation (ITI), leakage of lactate dehydrogenase, a biomarker of cell injury, was significantly increased in all exposure groups. Further, repeated exposure of rats to CPC for 28 days caused a decrease in body weight of the high-exposure group and the relative weights of the lungs and kidneys of the high recovery group, but no changes were evident in the histological and serum chemical analyses. The bronchoalveolar lavage fluid (BALF) analysis showed a significant increase in proinflammatory cytokines interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α levels. ITI of CPC induced focal inflammation of the pulmonary parenchyma in rats' lungs. Our study demonstrated that TNF-α was the most commonly secreted proinflammatory cytokine during CPC exposure in both in vitro and in vivo models. Polymorphonuclear leukocytes in the BALF, which are indicators of pulmonary inflammation, significantly increased in a concentration-dependent manner in all in vivo studies including the ITI, acute, and subacute inhalation assays, demonstrating that PMNs are the most sensitive parameters of pulmonary toxicity.

In water, sodium dichloroisocyanurate (NaDCC), a source for chlorine gas generation, releases free available chlorine in the form of hypochlorous acid, a strong oxidizing agent. NaDCC has been used as a disinfectant in humidifiers; however, its inhalation toxicity is a concern. Seven-week-old rats were exposed to NaDCC doses of 100, 500, and 2500 μg·kg−1body weight by intratracheal instillation (ITI) to investigate pulmonary toxicity. The rats were sacrificed at 1 d (exposure group) or 14 d (recovery group) after ITI. Despite a slight decrease in body weight after exposure, there was no statistically significant difference between the control and NaDCC-treated groups. A significant increase in the total protein level of the bronchoalveolar lavage fluid (BALF) was observed in the exposure groups. Lactate dehydrogenase leakage into the BALF increased significantly ( p < 0.01) in the exposure groups; however, recovery was observed after 14 d. The measurement of cytokines in the BALF samples indicated a significant increase in interleukin (IL)-6 in the exposure group and IL-8 in the recovery group. Histopathological examination revealed inflammatory foci and pulmonary edema around the terminal bronchioles and alveoli. This study demonstrated that ITI of NaDCC induced reversible pulmonary edema and inflammation without hepatic involvement in rats.

Background/Aim: The use of glycolic acid is present in a variety of consumer products, including medicines, cleaners, cosmetics, and paint strippers. It has recently led to concerns about toxicity from inhalation exposure. Herein, the pulmonary toxicity of glycolic acid was investigated in rats. Materials and Methods: We conducted acute (~458 mg/m(3)) and sub-acute (~49.5 mg/m(3)) inhalation tests to identify the potential toxicities of glycolic acid. Results: Inhalation exposure to glycolic acid in the acute and subacute inhalation tests did not cause any specific changes in clinical examinations, including body weight, organ weight, hematology, serum biochemistry, and histopathology. The polymorphonuclear neutrophils (PMNs) and inflammatory cytokines in Bronchoalveolar lavage fluid (BALF) increased in rats exposed to single and repeated inhalations. In the sub-acute test, the changes induced by glycolic acid were minor or returned to normal during the recovery period. Conclusion: The No Observed Adverse Effect Concentration (NOAEC) for the nasal and pulmonary toxicity of glycolic acid was determined to be over 50 mg/m(3) at the end of a 28-day inhalation test in male rats.

We present a novel and in-situ strategy to synthesize silver nanoparticles (AgNPs) onto cotton, leather, and silk fabrics by three different methods: a green method, a chemical method, and a composite of the green and chemical methods. The in-situ green synthesis was achieved with Aegle marmelos fruit pulp extract while the chemical synthesis utilized NaOH. To validate the green synthesis of AgNPs, various instrumental techniques were used including UV–Vis spectrophotometry, HR-TEM, FTIR, and XRD. The chemical and composite methods reduce Ag+ onto cotton, leather, and silk fabrics upon heating, and alkaline conditions are required for bonding to fibers; these conditions are not used in the green synthesis protocol. The composite technique used to bond AgNPs onto various fabrics provides significant color coordination, color fastness, bulk properties of the leather, and excellent antibacterial activity. In addition, FE-SEM images show the binding patterns of AgNPs on the fabric specimens.

Many consumer products used in our daily lives result in inhalation exposure to a variety of chemicals, although the toxicities of the active ingredients are not well known; furthermore, simultaneous exposure to chemical mixtures occurs. Sodium metabisulfite (SM) and propylene glycol (PG) are used in a variety of products. Both the cytotoxicity and the sub-acute inhalation toxicity of each chemical and their mixtures were evaluated. Assays for cell viability, membrane damage, and lysosome damage demonstrated that SM over 100 μg/ml induced significant cytotoxicity; moreover, when PG, which was not cytotoxic, was mixed with SM, the cytotoxicity of the mixture was enhanced. Solutions of 1, 5, and 20% SM, each with 1% PG solution, were prepared, and the whole body of rats was exposed to aerosols of the mixture for 6 h/day, 5 days/week for 2 weeks. The rats were sacrificed 1 (exposure group) or 7 days (recovery group) after termination of the exposure. The actual concentration of SM in the low-, medium-, and high-exposure groups was 3.91 ± 1.26, 35.73 ± 6.01, and 80.98 ± 5.47 mg/m3, respectively, and the actual concentration of PG in each group was 6.47 ± 1.25, 8.68 ± 0.6, and 8.84 ± 1.77 mg/m3. The repeated exposure to SM and PG caused specific clinical signs including nasal sound, sneeze, and eye irritation which were not found in SM single exposure. In addition, the body weight of treatment group rats decreased compared to that of the control group rats in a time-dependent manner. The total protein concentration and lactate dehydrogenase activity in the bronchoalveolar lavage fluid (BALF) increased. Histopathological analysis of the lungs, liver, and nasal cavity was performed. Adverse effects were observed in the nasal cavity, with squamous cell metaplasia identified in the front of the nasal cavity in all high-exposure groups, which completely recovered 7 days after exposure was terminated. Whereas inhalation of SM for 2 weeks only reduced body weight in the high-dose group, inhalation of SM and PG mixtures for 2 weeks significantly decreased body weight and induced metaplasia of the respiratory epithelium into squamous cells in the medium- and high-dose groups. In conclusion, PG potentiated the toxicity of SM in human lung epithelial cells and the inhalation toxicity in rats.

In the present study, surface of laccase producing Ceriporia lacerata was modified using 4-bromobutyryl chloride andpolyethylenimine. The modified biomass was freeze dried and utilized as a biosorbent for the removal of Ni(II) fromaqueous solution. The physicochemical properties of the biosorbent were analyzed using scanning electron microscopyand Fourier transform infrared spectroscopy. Batch experiments were carried out as a function of contact time (0-60 min),pH (2 to 8), adsorbent dosage (25-150 mg), and initial Ni(II) concentration (25-125 mg/L). The results indicate that surfacemodified biosorbent effectively adsorbed (9.5 mg/0.1 g biomass) Ni(II) present in the solution. The equilibrium adsorptiondata were modeled with different kinetic and isotherm models. The Ni(II) adsorption followed pseudo-first-order kinetics(R 2 = 0.998) and Langmuir isotherm (R 2 = 0.994) model. Hydroxyl and carbonyl functional groups present in biomass playa major role in the adsorption of Ni(II). The adsorbed Ni(II) from the biosorbent was successfully desorbed (85%) by 1 MHCl. The results of the study indicate that the surface modified C. lacerate biomass could be used for the treatment ofNi(II) contaminated ground waters.Key words : Adsorption isotherm, Ceriporia lacerata, Heavy metal, Kinetics, Nickel

Introduction This study aims to evaluate the effectiveness of zooming in improving screen-reader performance in reporting digital mammograms. Method Two experiments were conducted. In the first experiment, 5 readers were asked to report 59 two-view bilateral mammograms retrospectively with zooming function turned off. The second session was similar to the first one except that zooming was enabled. The task of readers was to assess if the mammograms were normal or abnormal and rate the confidence levels for each of the lesion they detected. The reader performances were evaluated via case sensitivity, lesion sensitivity, specificity, receiver operating characteristics (ROC) area under the curve (AUC) and jackknife free-response receiver operating characteristics (JAFROC) figure of merit (FOM). Results There was no significant improvement in overall reader performance in detecting abnormalities in zooming condition compared with no zooming in terms of case sensitivity (96% and 87%, P = 0.285) or lesion sensitivity (88% and 81%, P = 0.224). However, differences in ROC AUC and JAFROC FOM (P ≤ 0.05) were found in two readers when they performed the test set with zooming function. Conclusion The results suggested that the use of the zooming function did improve the performance of some readers in detecting abnormal cases.

Aim Sarcoidosis is a multisystem granulomatous disease. This condition has a documented association with the diagnosis of melanoma and can be induced in melanoma patients receiving anti-neoplastic therapy. We evaluated a case series of melanoma patients who developed immunotherapy-induced sarcoidosis. Methods Three patients with melanoma (n = 1 resected Stage III, n = 2 metastatic) treated with anti-programmed cell death (PD)-1 antibody therapy at two institutions developed biopsy-proven sarcoidosis. We used mass cytometry to determine expression of the relevant chemokine receptors (CR) by peripheral blood mononuclear cells for two of the three patients who developed sarcoidosis and 13 melanoma patients who did not. Blood samples were collected before receiving PD-1 checkpoint inhibitor therapy. Results Immunophenotypic analysis demonstrated abnormally high numbers of circulating Th17.1 (CCR6+CCR4−CXCR3+CCR10−) cells prior to commencing PD-1 checkpoint inhibitor therapy in five of 15 melanoma patients, including both the patients who developed sarcoidosis during the course of therapy. Conclusion Our findings support prior literature implicating Th17.1 cells in the pathogenesis of sarcoidosis. However, we demonstrate these findings in patients with melanoma prior to administration of checkpoint therapy and before the onset of clinically symptomatic sarcoidosis. The identification of elevated Th17.1 cells in melanoma patients who have not developed sarcoidosis may reflect the established association between melanoma and sarcoidosis. With some patients receiving these agents over a prolonged period, the clinical course of immunotherapy-induced sarcoidosis is uncertain.

Consumption of trans-fatty acids has been linked to an increased risk of cardiovascular diseases, such as atherosclerosis. Milk and dairy products contain trans-fatty acids, such as transvaccenic acid (TVA) and conjugated linoleic acid (CLA). Although artificially hydrogenated trans-fatty acids (e.g., elaidic acid (EA)) are known to induce atherosclerosis, it is unclear whether ruminant trans-fats, such as TVA, are associated with such diseases. Therefore, we investigated the effects of TVA on vascular smooth muscle cells (VSMCs). VSMCs were treated with TVA, CLA, and EA at 0-100 μM for 24 h. Cell proliferation and migration increased upon treatment with EA, not with TVA and CLA. EA increased protein expression of proliferation-associated proteins (cyclin-dependent kinase 4 (CDK4) and cyclin D1), while TVA and CLA decreased CDK4 expression. These results suggest that TVA is not as risky as other trans-fatty acids such as EA in the vascular system.

In this study, we synthesized ( E )-2-cyano-3-(substituted phenyl)acrylamide ( CPA ) derivatives which possess a linear β-phenyl-α,β-unsaturated carbonyl scaffold and examined their inhibitory activities against tyrosinase. CPA analogs exerted inhibitory activity against mushroom tyrosinase. Results from the docking simulation indicated that CPA2 could bind directly to the active site of mushroom tyrosinase and the binding affinity of CPA2 for tyrosinase might be higher than that of kojic acid, a well-known potent tyrosinase inhibitor. In B16F10 cells, CPA2 significantly suppressed tyrosinase activity and melanogenesis in a dose-dependent manner. At the concentration of 25 μM, CPA2 exhibited tyrosinase inhibitory activity comparable to that of kojic acid with no cytotoxic effect. Results from the present study suggest that CPA2 bearing a linear β-phenyl-α,β-unsaturated carbonyl scaffold may be the potential candidate for treatment of diseases associated with hyperpigmentation and that a linear β-phenyl-α,β-unsaturated carbonyl scaffold might be closely related to potent tyrosinase inhibition.

This study aims to evaluate the effectiveness of zooming in improving screen-reader performance in reporting digital mammograms.Two experiments were conducted. In the first experiment, 5 readers were asked to report 59 two-view bilateral mammograms retrospectively with zooming function turned off. The second session was similar to the first one except that zooming was enabled. The task of readers was to assess if the mammograms were normal or abnormal and rate the confidence levels for each of the lesion they detected. The reader performances were evaluated via case sensitivity, lesion sensitivity, specificity, receiver operating characteristics (ROC) area under the curve (AUC) and jackknife free-response receiver operating characteristics (JAFROC) figure of merit (FOM).There was no significant improvement in overall reader performance in detecting abnormalities in zooming condition compared with no zooming in terms of case sensitivity (96% and 87%, P = 0.285) or lesion sensitivity (88% and 81%, P = 0.224). However, differences in ROC AUC and JAFROC FOM (P ≤ 0.05) were found in two readers when they performed the test set with zooming function.The results suggested that the use of the zooming function did improve the performance of some readers in detecting abnormal cases.