• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.4
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• pp.269-282
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• 2017

Objectives: Currently, masks against yellow dust and fine particulates are being certified with no consideration of facial dimensional variations among children and adults. The aims of this study were to develop masks against yellow dust and fine particulates for children in Korea and provide basic data to suggest new test methods for mask certification that consider the breathing capacity of children. Methods: A total of 730 study participants aged from six to 13 years old were recruited in the Seoul, Gyeonggi, and Incheon region. This study used a 3D scanning instrument to obtain 16 facial anthropometric data points. Literature reviews, a comparison of breathing capacity between adults and children, and analysis of children's pulmonary physiological data were conducted in order to suggest new test standards for certifying children's masks against yellow dust and fine particulates. In addition, types of children's masks, choice of wearing a mask or not, and reasons for not wearing masks were surveyed. Results: Based on a clustering analysis of participants' facial dimensions, facial shapes were classified into three groups: small, medium, and large. The sizes of children's masks were subtracted by using 3D sketch techniques(Large: $121.25mm{\times}89.46mm$, Medium: $111.92mm{\times}78.55mm$, Small: $102.13mm{\times}72.87mm$). In certifying children's mask, flow rates of $60{\ell}/m$ for the filtering efficiency test and $20{\ell}/m$ for the breathing resistance test were recommended, since children's pulmonary physiological capacity is about 60-70% of adults' pulmonary capacity. Conclusions: The results of this study suggest that three mask sizes for children would be sufficient and practical for providing protection against yellow dust and fine particulates. Revising current test methods for certifying respiratory protective devices for children is important, since children's pulmonary physiological capacity substantially differs from that of adults. Therefore, it is recommended that new test standards for certifying children's masks be promulgated in the near future.

• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.80-86
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• 1997

The objective of this study was to investigate how resistant poplar hybrid makes compensation to ozone stress. Growth, net assimilation rate and initial Rubisco activity were investigated. This study elucidates the physiological mechanisms associated with ozone sensitivity and resistance in 3 selected $F_2$ hybrids, a family originating from a cross between Populus trichocarpa${\times}$P. deltoides. Open-top chambers were used. Ozone concentrations varied from 90 to 115 ppb for 126 days, 6 to 9 hours in a day. This study tested the hypothesis that resistant poplar hybrid maintains the biomass production to ozone exposure via increased net assimilation rate and Rubisco activity. Growth, biomass, net assimilation rate and initial Rubisco activity were generally reduced by ozone treatment. In the tree parts, root under ozone stress was the most sensitive part. Reduced allocation of photosynthates to root growth might be due to increased respiratory demands for maintenance and repair of aboveground tissue damaged by ozone stress. Maintenance or increases remaining leaves in photosynthetic rates and Rubisco activity in resistant clone in response to ozone treatment were the results of biological compensation to ozone stress.

• Journal of Haehwa Medicine
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• v.9 no.1
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• pp.201-214
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• 2000

Precise and detailed clinical research and evaluation based on objective standards are imperative factors in securing reliability of a clinical test. Built on this principle, this clinical test has been conducted during the period between March 1999 and March 2000 dealing with 31 outpatients treated with ShiHo-GuizhiTang or ShiHo-GuizhiTang modify and ShiHo-GuizhiTang mixed prescriptions at the Sung-bo ORIENTAL MEDICAL CLINIC. A variety of information relating to those patients has been collected and analyzed under such criteria as precise diagnoses and their clinical effectiveness. The analysis was duly based on "The theory of cold syndrome". Then, the 31 patients' individual clinical information was compared one another by breaking down the results into sub-categories including gender, age, disease, main symptom, blood pressure, pulse beats, syndrome of abdomen, treatment period, modify and mixed prescription, and evaluation. The result of this clinical test can be summarized as follows: First, ShiHo-GuizhiTang appears to be more frequently prescribed in the case of female patients than in the case of male patients despite the fact that it does not necessarily need to be applied only to female. In addition, the numbers of prescriptions of ShiHo-GuizhiTang in the two age groups consisting of elementary school children and economically active adults respectively were the highest among other age groups. Second, ShiHo-GuizhiTang proved to be most effective in treatment for respiratory ailments and arthritis. Third, ShiHo-GuizhiTang brought down blood pressure of hypertension patients and at the same time benefited patients with normal or lower-than-normal blood pressure who were vulnerable to diseases due to low disease-resistance. Fourth, ShiHo-GuizhiTang was effective in the case of frequent pulse(rapid pulse) and thereby indicating the fact it carries Taiyang superficies syndrome. 지맥 arises from suppressed immune responses owing to adrenocortical hormones. ShiHo-GuizhiTang controls and revitalizes those suppressed immune systems which stem from slow pulse and, as a consequence of that process, helps them return to normal condition of pulse. Fifth, from the standpoint of syndrome of abdomen, feeling of obstruction in the epigastrium serves as an important standard in the process of diagnosing diseases and evaluating effectiveness of treatments. Sixth, according to the results of the clinical test with the 31 patients, a total of 81 percent of test subjects benefited from the treatment. The figure is the sum of 52 percent of I-class (both main symptom and accompanying symptoms had been eliminated) and 29 percent of II-class (part of main symptom and accompanying symptoms had been eliminated) respectively. All told it is safe to say that ShiHo-GuizhiTang can elect to be a viable clinical treatment. In conclusion, it is estimated that this clinical study has drawn up guidelines for objective diagnostic standards and evaluation on specific treatments' effectiveness. This will lead to more general application of ShiHo-GuizhiTang. On top of that, this study could also provide an opportunity to stress the significance of ShiHo-GuizhiTang and ShiHo-GuizhiTang modify and ShiHo-GuizhiTang mixed prescriptions as an alternative treatment for collagen disease which comes from environmental degradation and pollution.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.69-78
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• 1967

Kim, Jong Hyup, (Div. of Biology, Atomic Energy Research Institute.) Studies on the Cellular Metabolism in Microorganisms as influenced by Gamma-irradiation(II). On respiration rate and dehydrogenase activity of yeast cells irradiated by gamma ray from cobalt-60. 1. Oxygen uptake rate of the gamma irraiated yeast cells had been measured with Warburg's manometer, and the $O_{2}$-uptake was compared with those of normal cells. The rate of endogetious respiration increases in its $O_2$-uptake at 150, 000 rentgen dose, and at higher rentoen doses it was decreased. Exogenous respiration begin to decrease in its O_2$-uptake at 5, 000r. doses of irradiation, further decrease with increasing of doses unproportionally. 2. It appears that plasma-membrane and nuclear membrane of yeast cells have changed and denatured by gamma-irradiation, as exogenous respiration of glucose had been decreased at a dose of 200, 000r's irradiation. 3. The activity of glucose, alcoholic, lactic, succinic and glutamic deliydrogenase (G.D.H., A.D.H., L.D.H., S.D.11., and GL.D.H.) in the gamma irradaited cells had been assayed by T.T.C.(Triphenyl tetrazolium chloride) method and spectrophotometry, the obtained results were compared with those of normal cells. 4. At a dose of and 10, 000 rentgens' irradiation of gamma ray, the activty of each debydrogenase (G.D.H., A.D.H., L.D.H., ) shows a sharp and highest peak in optical absorbalicy, but each abtivity of S.D.H and Gl.D.H shows its' maximum peak at a dose of 30, 000r. 5. The curve of each dehydrogenase activity was found to be rhythmical according to dose-rate of gamma irradiation. 6. Comparing with activity of debydrogenase each other, the maximum peak in optical absorbency can be arranged according to order as follows; glucose > alcoholoic > lactic > glutamic > succinic, this order is identical to the order of breakdown utility in respiration of normal yeast cells. 7. The activity of dehydrogenase experimented exhibit a resistance against gamma irradiation at lethal dose of cells, and the activity of dehydrogenase are found to be much resistant than those of respiratory system. We may assume that the membrane substrate of mitochondria or cytoplasm had been destructed by gamma-irradiation much more than that of dehydronase system.

• Journal of Dental Anesthesia and Pain Medicine
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• v.17 no.4
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• pp.265-270
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• 2017

Background: Endotracheal intubation during anesthesia induction may increase airway resistance ($R_{aw}$) and decrease dynamic lung compliance ($C_{dyn}$). We hypothesized that prophylactic treatment with a transdermal ${\beta}2$-agonist tulobuterol patch (TP) would help to reduce the risk of bronchospasm after placement of the endotracheal tube. Methods: Eighty-two American Society of Anesthesiologists (ASA) category I or II adult patients showing obstructive patterns were divided randomly into a control and a TP group (n = 41 each). The night before surgery, a 2-mg TP was applied to patients in the TP group. Standard monitors were recorded, and target controlled infusion (TCI) with propofol and remifentanil was used for anesthesia induction and maintenance. Simultaneously, end-tidal carbon dioxide, $R_{aw}$, and $C_{dyn}$ were determined at 5, 10, and 15 min intervals after endotracheal intubation. Results: There was no significant difference in demographic data between the two groups. The TP group was associated with a lower $R_{aw}$ and a higher $C_{dyn}$, as compared to the control group. $R_{aw}$ was significantly lower at 10 min (P < 0.05) and 15 min (P < 0.01), and $C_{dyn}$ was significantly higher at 5 min (P < 0.05) and 15 min (P < 0.01) in the TP group. A trend towards a lower $R_{aw}$ was observed showing a statistically significant difference 5 min after endotracheal intubation (P < 0.01) in each group. Conclusions: Prophylactic treatment with TP showed a bronchodilatory effect through suppressing an increase in $R_{aw}$ and a decrease in $C_{dyn}$ after anesthesia induction without severe adverse effects.

• Korean Journal of Veterinary Service
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• v.43 no.4
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• pp.227-236
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• 2020

In this study, we have developed 3D8 scFv transgenic pig (TG) by microinjection of fertilized one-cell pig zygotes (2.17%). The effect of 3D8 scFv TG on porcine reproductive and respiratory syndrome virus (PRRSV) resistance were evaluated through PRRSV VR2332 (1×103 TCID50/mL) challenge and transmission experiments. As a result, the average daily weight gain (ADWG) of TG increased compared to the wild type pigs (WT) in PRRSV challenge groups and the serum viremia levels of the TG was significantly lower than of WT on the 7 day and 21 day after infection, meaning that the viral shedding was suppressed by 3D8 scFv expression. These results suggest that the expression of 3D8 scFv in pig could suppress spreading of infected virus to pigs sharing a room.

• Journal of Ginseng Research
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• v.47 no.1
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• pp.123-132
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• 2023

Background: Pseudotyped virus systems that incorporate viral proteins have been widely employed for the rapid determination of the effectiveness and neutralizing activity of drug and vaccine candidates in biosafety level 2 facilities. We report an efficient method for producing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus with dual luciferase and fluorescent protein reporters. Moreover, using the established method, we also aimed to investigate whether Korean Red Ginseng (KRG), a valuable Korean herbal medicine, can attenuate infectivity of the pseudotyped virus. Methods: A pseudovirus of SARS-CoV-2 (SARS-2pv) was constructed and efficiently produced using lentivirus vector systems available in the public domain by the introduction of critical mutations in the cytoplasmic tail of the spike protein. KRG extract was dose-dependently treated to Calu-3 cells during SARS2-pv treatment to evaluate the protective activity against SARS-CoV-2. Results: The use of Calu-3 cells or the expression of angiotensin-converting enzyme 2 (ACE2) in HEK293T cells enabled SARS-2pv infection of host cells. Coexpression of transmembrane protease serine subtype 2 (TMPRSS2), which is the activator of spike protein, with ACE2 dramatically elevated luciferase activity, confirming the importance of the TMPRSS2-mediated pathway during SARS-CoV-2 entry. Our pseudovirus assay also revealed that KRG elicited resistance to SARS-CoV-2 infection in lung cells, suggesting its beneficial health effect. Conclusion: The method demonstrated the production of SARS-2pv for the analysis of vaccine or drug candidates. When KRG was assessed by the method, it protected host cells from coronavirus infection. Further studies will be followed for demonstrating this potential benefit.

• Clean Technology
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• v.29 no.2
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• pp.135-144
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• 2023

Pseudomonas aeruginosa and Staphylococcus aureus are the two most frequently encountered pathogens responsible for chronic wound infections, often coexisting in such cases. These infections exhibit heightened virulence compared to single infections, leading to unfavorable patient outcomes. The interaction among microorganisms within polymicrobial infections has been shown to exacerbate disease progression. Polymicrobial infections, prevalent in various contexts such as the respiratory tract, wounds, and diabetic foot, typically involve diverse microorganisms, with Pseudomonas aeruginosa and Staphylococcus aureus being the most commonly identified pathogens. This study aimed to compare the growth patterns of bacteria under a concentration gradient of toxic chemicals, focusing on a Gram-negative strain of Pseudomonas aeruginosa and a Gram-positive strain of Staphylococcus aureus. The minimum inhibitory concentration (MIC), which signifies the concentration at which bacterial growth is inhibited, was determined by performing broth microdilution and assessing the bacteria's growth curves. The growth curves of both Pseudomonas aeruginosa and Staphylococcus aureus were confirmed, and the exponential growth phases were applied to calculate the doubling times of bacteria. The MIC value for each toxic chemical was determined through broth microdilution. These results allowed for the identification of disparities in growth rates between Gram-positive and Gram-negative bacteria, as well as differences in resistance to individual toxic substances. We expect that this approach has a strong potential for further development towards the innovative treatment of bacteria-associated infections.

• Safety and Health at Work
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• v.14 no.4
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• pp.457-466
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• 2023

Background: During hot environment work tasks with whole-body enclosed anti-bioaerosol suit, the combined effect of heavy sweating and exhaled hot humid air may cause the N95 medical respirator to saturate with water/sweat (i.e., water-blocking). Methods: 32 young male subjects with different body mass indexes (BMI) in whole-body protection (N95 medical respirator + one-piece protective suit + head covering + protective face screen + gloves + shoe covers) were asked to simulate waste collecting from each isolated room in a seven-story building at 27-28℃, and the weight, inhalation resistance (R_f), and aerosol penetration of the respirator before worn and after water-blocking were analyzed. Results: All subjects reported water-blocking asphyxia of the N95 respirators within 36-67 min of the task. When water-blocking occurred, the R_f and 10-200 nm total aerosol penetration (P_t) of the respirators reached up to 1270-1810 Pa and 17.3-23.3%, respectively, which were 10 and 8 times of that before wearing. The most penetration particle size of the respirators increased from 49-65 nm before worn to 115-154 nm under water-blocking condition, and the corresponding maximum size-dependent aerosol penetration increased from 2.5-3.5% to 20-27%. With the increase of BMI, the water-blocking occurrence time firstly increased then reduced, while the R_f, P_t, and absorbed water all increased significantly. Conclusions: This study reveals respirator water-blocking and its serious negative impacts on respiratory protection. When performing moderate-to-high-load tasks with whole-body protection in a hot environment, it is recommended that respirator be replaced with a new one at least every hour to avoid water-blocking asphyxia.

• Journal of Chest Surgery
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• v.38 no.4 s.249
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• pp.277-283
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• 2005

Arterial oxygen saturation $(SaO_2)$ instability frequently takes place after systemic-pulmonary shunt without shunt occlusion. We analyzed actual incidence and risk factors for $SaO_2$ instability after shunt operations, and possible mechanisms were speculated on. Material and Method: Ninety three patients, who underwent modified Blalock-Taussig shunt from January 1996 to December 2000, were enrolled in this study. Adequacy of shunt was verified in all patients, either by ensuing one ventricle or biventricular repair later on or by appropriate pulmonary artery growth on postoperative angiogram. Age, body weight, hemoglobin level at operation were 3 day to 36 years (median: 1.8 months), 2.5kg to 51kg (median: 4.1kg) and $10.7\~24.3$ gm/dL (median: 15.2 gm/dL) respectively. Preoperative diagnoses were functional single ventricle with pulmonary stenosis or atresia in 39, tetralogy of Fallot in 38 and pulmonary atresia with intact ventricular septum in 16. Pulmonary blood flow (PBF) was maintained pre-operatively by patent ductus or previous shunt in 64 and by forward flow through stenotic right ventricular outflow tract (RVOT) in 29. $SaO_2$ instability was defined as $SaO_2$ less than $50\%$ for more than 1 hour with neither anatomic obstruction of shunt nor respiratory problem. Result: 10 patients $(10.7\%)$ showed $SaO_2$ instability after shunt operation. After shunt occlusion was ruled out by echocardiogram, they received measures to lower pulmonary vascular resistance (PVR), which worked within a few hours in all patients. Risk factors for $SaO_2$ instability included older age at operation (p=0.039), lower preoperative $SaO_2$ (p=0.0001) and emergency operation (p=0.001). PBF through stenotic RVOT showed marginal statistical significance (p=0.065). Conclusion: $SaO_2$ instability occurs frequently after shunt operation, especially in patients with severe hypoxia pre-operatively or unstable clinical condition necessitating emergency operation. Temporary elevation of pulmonary vascular resistance is a possible mechanism in this specific clinical setting.