• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.31 no.3
• /
• pp.185-193
• /
• 2021

Objectives: Inhalation toxicity testing of chemical substances to identify carcinogenicity requires a long time and considerable cost, so the selection of test candidates is a very important aspect. This study was performed to determine optimal procedures for selecting carcinogenic inhalation toxicity test substances as conducted by the Occupational Safety and Health Research Institute (OSHRI). Methods: At the beginning, a database was constructed containing complex information such as usage amount, hazard, carcinogenicity prediction, and testability in order to select chemicals requiring carcinogenicity testing. Selection of test substances was carried out with priority given to usage, carcinogenicity, and testability. Results: Chemicals used in large quantities in industrial fields and strongly suspected of carcinogenicity were winnowed down to 12 substances, and these substances were scheduled for future testing by OSHRI. Conclusions: For the stable and reliable operation of carcinogenicity tests as conducted by OSHRI, this study standardized the procedures for selecting carcinogenicity test substances and suggested the introduction of various carcinogenicity prediction techniques.

• Biomedical Science Letters
• /
• v.29 no.4
• /
• pp.231-241
• /
• 2023

Messenger RNA (mRNA)-based vaccines and treatments have recently emerged as a promising strategy. Naked mRNA presents various limitations for direct delivery. Therefore, in this paper, Lipid Nanoparticles (LNPs) were utilized for the delivery of mRNA. Lipid nanoparticle (LNP) mRNA systems are highly effective as vaccines, but their efficacy for pulmonary delivery has not yet been fully established. Additionally, research on effective delivery systems and administration methods for vaccines is required to resolve the stability and degradation issues associated with naked mRNA delivery. This study aimed to determine mRNA delivery efficiency via the inhalation of a lipid nanoparticle (LNP) formulation designed specifically for pulmonary delivery. To this purpose, we built a library of seven LNP configurations with different lipid molar and N/P ratios and evaluated their encapsulation efficiency using gel retardation assay. Among the tested LNPs, LNP1, LNP2-2, and LNP3-2 demonstrated high transfection efficiency in vitro based on FACS analyses luciferase assays, and intracellular accumulation tests. The mRNA delivery efficiencies of the selected LNPs after inhalation and intravenous injection were compared and evaluated. LNP2-2 showed the highest mRNA expression in healthy mouse lungs when aerosolized and was found to be non-toxic. These results indicate that LNP2-2 is a promising carrier for lung mRNA delivery via inhalation.

• Journal of Veterinary Clinics
• /
• v.34 no.2
• /
• pp.135-139
• /
• 2017

This study was performed to evaluate the clinical efficacy of alfaxalone for induction of inhalation anesthesia in small animal practice. Patient data were collected according to anesthetic records (136 dogs and 14 cats) presented to the Veterinary Medical Teaching Hospital of Seoul National University for surgeries and diagnostic imaging from July 2013 to March 2014. Anesthetic results included signalment, American Society of Anesthesiologists (ASA) grade, premedicated drugs, procedures, induction quality, and recovery after anesthesia. One hundred fifty anesthetic events were classified according to the ASA grade. Three patients were ASA grade I, 52 patients grade II, 86 patients grade III, and 9 patients grade IV, respectively. The most common premedication was midazolam and hydromorphone combination (n = 59, 39.3%) follow by acepromazine and hydromorphone combination (n = 22, 14.7%). The majority of anesthesia procedures were diagnostic imaging (n = 33, 22.0%) and ophthalmic surgeries (n = 31, 20.7%), followed by soft tissue surgeries (n = 27, 18.0%), and orthopedic surgeries (n = 20, 13.3%). Intravenous alfaxalone provided smooth induction for inhalation anesthesia in almost cases, but transient apnea and twitching/paddling were observed after induction and during recovery, respectively. In addition, alfaxalone did not show pain response during intravenous administration. Alfaxalone showed smooth induction of inhalation anesthesia in dogs and cats with mild to severe systemic disease (ASA 2-4). Alfaxalone was considered as an acceptable induction agent for patients with higher risk in small animal practice.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.13 no.1
• /
• pp.76-84
• /
• 2002

Objectives：This study was conducted to investigate the effect of oxygen on attention and memory functions in healthy adolescents. Methods：The participant subjects were recruited from local advertisement. All subjects are students attending ordinary middle and high school. Their degree of achievement was average or below average. Before the study, its nature and purpose were fully explained to the patients and their parents, and a written informed consent was obtained from each child's parent and a written assent from each child for entire the procedure. The Ethics Committee and Clinical Research Committee of Gyeongsang National University Hospital approved the protocol. For baseline assessment, all subjects received tests for attention and memory. All tests were conducted by a certified psychologist. Stroop test, continuous performance test and trail making test A and B were used for evaluation of attention. As memory tests, we used memory assessment scale(MAS), standardized memory assessment tools. Ten to fourteen days after initial assessments, same tests was applied to the same subjects after prior 5 minute oxygen inhalation. Results：1) Attention test：Improved performances in trail making part B, and stroop test were found in normobaric oxygen inhalation group compared to air inhalation group. Improved reaction time in those tests seemed to reflect the enhanced executive prefrontal activity. 2) Memory test：More words and digits memorization were found in short-term memory subscale score in MAS in oxygen inhalation group compared to air inhalation group. This finding suggested the improved working memory function after oxygen inhalation. Conclusion：Though interpreted cautiously, these results suggested that normobaric oxygen inhalation could enhance executive function and working memory of prefrontal lobe. Further study, however, should be performed to investigate the mechanism of effects of oxygen on cognitive enhancement.

• The Korean Journal of Pesticide Science
• /
• v.15 no.4
• /
• pp.507-528
• /
• 2011

Agricultural workers who mix/loads and spray pesticide in fields expose to pesticide through dermal and inhalation routes. In such situation, exposed amount should be measured quantitatively for reasonable risk assessment. Patch, gloves, socks and mask will be good materials for monitoring for dermal exposure while personal air monitor equipped with solid adsorbent and air pump will be a tool for inhalation exposure. For extrapolation of absorbed amount in dermal exposure matrices and of trapped amount in solid sorbent to total deraml or inhalation exposure, Korean standard body surface area and respiration rate were proposed in substitution of EPA data. Important exposure factors such as clothing and skin penetration ratio of dermal and inhalation exposure were suggested based on Spraying time for exposure monitoring must be long enough that the amount of pesticide to get absorbed/trapped in exposure matrices results in reasonable analytical value. In domestic case for the both of speed sprayer and power spray machine, spraying time of 20~40 minutes (0.1~0.2 ha) will be reasonable per single replicate before extrapolating to 4 hours a day with triplicates experiment.

• The Korean Journal of Physiology
• /
• v.9 no.2
• /
• pp.17-22
• /
• 1975

Adult nonpregnant female rabbits were subjected to the study of the effects of carbon monoxide inhalation on the uterine motility. Animals were anesthetized with intravenous injection of nembutal, 35 mg/kg, and the uteri were exposed. Polyethylene tubing which had a small hole near the blind tip was inserted in the loop and normal saline was infused at a constant rate of 1.5 ml/min. On the other end of the loop, an outlet of fluid was made. When a peristaltic wave proceeded to the hole, a rise of the pressure was ensued and it was transmitted to the pressure transducer, making an upward deflection of the recording pen on the physiograph. Carbon monoxide, 1,000 ppm in the concentration, was inhaled through a tracheal cannula for 30 minutes, following fresh air for 30 minutes. In some cases, pure oxygen was also supplemented for another 30 minutes. Uterine motility was expressed in terms of the impulse that was the time integral of the pressure and of the frequency of the peristaltic waves. The results obtained were as follows. 1. When 1,000 ppm carbon monoxide was inhaled for 30 minutes, the impulse dropped to $72{\pm}16.5%$ and the frequency to $75{\pm}22.7%$ of the values obtained before the gas administration. 2. By fresh air for 30 minutes, the impulse and the frequency restored to $77{\pm}25.7%$ and $92{\pm}21.1%$, respectively. 3. By the supplement of pure oxygen for 30 minutes, no remarkable improvement were revealed, showing $89{\pm}35.2%$ in the impulse and $91{\pm}10.8%$ in the frequency, respectively. 4. There was an appreciable discrepancy in the recovery courses of the impulse and the frequency, suggesting different mechanisms attributable to the alteration by carbon monoxide inhalation.

• The Journal of Pediatrics of Korean Medicine
• /
• v.20 no.1
• /
• pp.181-194
• /
• 2006

Objective : Author evaluate the effects of Citri Reticulatae Viride Pericarpium for the bronchial asthma using assesment of the vascular endothelial growth factor after Citri Reticulatae Viride Peicarpium was intravenously administered Ovalbumine(OVA)-sensitized and -challenged mice. Material and Methods : Twenty-four female mice, 8-10 weeks old and free of murine specific pathogens, were sensitized by intraperitoneal injection of OVA. Of the sensitized mice, ten mice didn't administrate Citri Reticulatae Viride Pericarpium and the other ten mice administrated Citri Reticulatae Viride Pericarpium. Mice were sensitized on the first and fourteen days introspectional injection of 20 ${\mu}g$ OVA. After$21^{st}\;22^{th}\;and\;23^{rd}$, the initial sensitization, the mice were challenged for 30 minutes with an aerosol of 1% OVA in saline. Citri Reticulatae Viride Pericarpium administered 200mg/kg in the tail of the mouse, one a day, for 7 days and beginning 14 days after first sensitization. Bronchoalveolar lavage was performed 72 hours after the last challenge, and total cell numbers in the BAL fluid were count. Also, lever of VEGF in the BAL fluid was measured by Enzyme immunoassays and Western blot analysis. Results: Total cell numbers in BAL fluid were significantly greater than from 72 hrs after OVA inhalation compared with cell numbers in the control group. However, there was no difference of the total cell numbers between OVA-challenge groups without Citri Reticulatae Viride Pericarpium, and OVA-challenge with Citri Reticulatae Viride Pericarpium. Enzyme immunoassay revealed that VEGF levels in the BAL fluids were significantly increased 72 hrs after OVA inhalation compared with levels in the control group. After administration of the Citri Reticulatae Viride Pericarpiu, the levels of the VEGF in BAL fluids 72 hrs after OVA inhalation reduced dramatically. Western blot analysis revealed that VEGF protein levels were increased in the all mice which were challenge with OVA, without administered Citri Reticulatae Viride Pericarpium, compared the normal mouse. However, in the groups of the administered Citri Reticulatae Viride Pericarpium, the VEGF protein level markedly decreased. Conclusion: Citri Reticulatae Viride Pericarpium might affect the treatment of the bronchial ashma as a inhibition of the VEGF.

• Journal of Korean Academy of Nursing Administration
• /
• v.12 no.3
• /
• pp.444-453
• /
• 2006

Purpose: The purpose of the study was to identify critical indicators for the development of efficient patient classification system in a emergency room. Method: This study involved following five steps. Step 1. Selection of the lists direct nursing services in the ER. Step 2. Measurement of the time of direct nursing services from Aug. 31st to Nov. 30th, 2005. Step 3. Classification of the patients according to the nursing care time. Step 4. The determination the critical indicators for different patient classes. Result: Determinate indicators were as follow: 3 items in the first group (vital sign checking, IV route starting, blood sampling), 3 items in the second group (vital sign checking, fluid infusion, blood sampling), 9 items in the third group (I/O checking, $O_{2}$ inhalation, suction, fluid infusion, IV bolus, Central catheter preparation & management, blood sampling, intubation preparation & management, postmortem management), 7 items in the fourth group (EKG monitoring, BP monitoring, $O_{2}$ inhalation, fluid infusion, using the specific drugs, CPR, postmortem management). Conclusion: This study can help future studies which measure nursing services standard time or assigns value to emergency nursing services.

• The Journal of Korea Assosiation for Disability and Oral Health
• /
• v.2 no.2
• /
• pp.142-146
• /
• 2006

Oral administration of chloral hydrate with hydroxyzine, nitrous oxide inhalation and intramuscular or intranasal administration of midazolam is the most commonly used pharmacological behavior management methods for the children in pre-cooperative stage or show negative behavior in pediatric dentistry. For oral administration of chloral hydrate with hydroxyzine, it is hard to apply to the patient refused to intake and with overweighted or elderly children and the effect of the drug decrease. Nitrous oxide and midazolam is anxiolytic agents and have limitation for properly managing the behavior of the children refuse to dental treatment. These occasions, deep sedation or general anesthesia can be considered. Although intravenous sedation with midazolam has many advantages such as, rapid onset and recovery, possible to titration and few side effect, no rebound effect by metabolites, the reports for, intravenous sedation with midazolam is insufficient in pediatric dentistry. We report the case in pre-cooperative stage. He is treated successfully under intravenous sedation with midazolam.

• Toxicological Research
• /
• v.14 no.3
• /
• pp.329-332
• /
• 1998

Ingredients and concentrations of organic solvents in 7 kinds of adhesive sold on the domestic market were qualitatively and quantitatively analysed. Vapor concentrations were also analysed to estimate inhalation concentratins when adhesives were abused to get high. Acetone, methyl ethyl ketone, methyl cyclopenatane, cyclohexane and toluene were identified to be used in domstic adhesives as solvents. When organic solvents of adhesives were vaporized in the vial at the room temprature for 30 mins, concentrations of organic solvents in air were in the range of 5,000~140,000ppm. Among these solvents, toluene, known to have strong hallucination effect, showed 5,000~35,000 ppm. The putative concentration of toluene in case of glue sniffing was estimated to be about 5,000ppm in consideration of glue sniffing circumstances. Toluene was found in all adhesives in this study, even adhesives which toluene was not described in label.