• 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 Life Science
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• v.28 no.7
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• pp.786-794
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• 2018

Silkworm (Bombyx mori) pupae have been widely worked in wound dressing, hepatoprotective activity, antigenotoxicity, control of glucose level and anti-cancer activity. To investigate the anti-obesity activity of ethanol extract of silkworm pupae powder fermented with Cordyceps militaris (ESfC), the free glycerol release and cAMP concentration as well as fat accumulation were measured in the primary adipocytes of SD (Sprague Dawley) rats and high fat diet (HFD)-treated C57BL/6 mice treated with 12 weeks. Firstly, the presence of the cordycepin with lipid lowering effect was confirmed in ESfC using HPLC analysis. The level of free glycerol and cAMP concentration was significantly increased in the primary adipocytes treated with high dose of ESfC ($400{\mu}g/ml$) although these levels were consistently maintained in other dose ESfC treated groups. In HFD-induced obesity model, the increased fat weight and size of adipocytes in HFD+Vehicle treated group was recovered in HFD+ESfC treated group. Also, the liver weight and the number of lipid droplets were higher in HFD+Vehicle treated group than No treated group. But, this level was significantly decreased in HFD+ESfC treated group compared with HFD+Vehicle treated group. Furthermore, a similar recovery was detected on the phosphorylation of periliphin and HSL, and ATGL expression. Overall, the results of the present study provide some scientific evidences that ESfC can stimulate lipolysis in primary adipocytes and prevent fat accumulation in HFD-treated obesity model, and therefore have the potential for use as anti-obesity agents to treat obese patient.

• Applied Microscopy
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• v.30 no.4
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• pp.377-387
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• 2000

There are a few tanycytes between the general ependymal cells lining the ependymal layer of the brain ventricle. These cells are considered as modified ependymal cells which possess a long basal process. Tanycytes are known to have an ability to communicate by absorbing substances from cerebrospinal fluid and transporting them to the blood vessels and/or to the neurons in the CNS. The third and fourth ventricular tanycytes were mainly studied as subjects but it's rare to find reports about the tanycytes of the area postrema. Glial fibrillary acidic protein is an intermediate filament protein that is expressed especially in astrocytes of the CNS. But GFAP is also found in filament of the tanycytes and its process. Therefore this study was carried out for the examination of the GFAP immunoreactive tanycytes lining the area postrema of the bat, and we also examined the ultrastructure of tanycytes using electron microscope. GFAP immunoreactive tanycytes were located in the caudal portion of the fourth ventricle, and especially mainly in the transitional zone between the floor of the caudal fourth ventricle and ependymal layer lining the area postrema. A few GFAP immunoreactive tanycytes were also found in the ependymal layer lining the area postrema, and some groups of tanycytes were found in the ependymal layer of the area postrema near the floor of the caudal fourth ventricle , The processes of tanycytes were stained deeply with anti-GFAP antibody. Especially the GFAP immunoreactive tanycytes lining the area postrema had very long processes that cross the whole width of the area postrema. In the electron microscope, the cell body of ependymal tanycyte was located on the ependymal layer and had a long basal process. Intermediate filaments were observed around the nucleus and well developed in the process of tanycrte. Longitudinal oriented long mitochondria and a few lipid droplets were also found in this process. After immunocytocheical staining, the gold particles were found only in the intermediate filaments. We could not determine the function of the tanycytes in the area postrema. Thus, further investigation is required to determine the functional relationship between the tanycytes and the area postrema in hibernating animal, the bat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1270-1278
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• 2010

Dietary effects of chicken treated with Hwangki-Beni Koji sauces (HBS) on serum and hepatic lipid profiles in rats fed high a fat and high cholesterol diet were investigated. Experimental plots (5 rats per each group) were divided into normal control diet group (NC), high fat and high cholesterol diet group (HFC), HFC plus 15% base sauce treated chicken supplemented diet group (HFC-BS), HFC plus 15% HBS-treated chicken supplemented diet group (HFC-HBS), and fed for 5 weeks. Feed intakes in HFC-HBS group were higher than those of HFC and HFC-BS groups, whereas body weight gain and feed efficiency ratio of the HFC-HBS group were lower than those of the HFC and HFC-BS groups. Serum alanine aminotransferase and aspartate aminotransferase activities of HFC-HBS group were significantly lower than those of HFC and HFC-BS groups. Level of serum triglyceride, total cholesterol and LDL-cholesterol in HFC-HBS group were 34.06%, 6.28% and 31.00% lower than those of HFC-BS group, respectively, whereas HDL-cholesterol level and atherogenic index in HFC-HBS group were 1.72-fold higher and 2.52-fold lower, respectively, than those of HFC-BS group. Level of hepatic total lipid, triglyceride and total cholesterol in HFC-HBS group were 9.53%, 5.25% and 22.20% lower than those of HFC-BS group, respectively. In the morphological results of liver, the hepatocytes of central vein lesion and intact hepatic cell plate are preserved well from steatosis in HFC-HBS group, whereas the hepatocytes in HFC and HFC-BS groups are distended by accumulation of multiple fat droplets, and sinusoids are occluded. In the above results, we expected that chicken treated with Hwangki-Beni Koji sauce may have functionalities of anti-obesity, anti-cholesterol and also, lowering anti-atherogenic index in high fat and high cholesterol diets.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.813-819
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• 2010

The intracellular lipid droplets were stained with Oil Red O dye and quantified. Compared to the control, lipid accumulation was significantly decreased by 19.4% with the treatment of LCM at the concentration of $1000\;{\mu}g$/mL. Intracellular triglyceride (TG) level was also reduced by 21% at the concentration of $1000\;{\mu}g$/mL. To determine the mechanism for the reduction in TG content, levels of glucose uptake and glycerol release were measured. Incubation of the 3T3-L1 adipocytes with LCM did not affect the cellular uptake of glucose. However, the level of free glycerol released into the cultured medium drastically increased by 24.3% with the treatment of LCM. In subsequent measurements using quantitative real-time PCR, mRNA levels of hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) except lipoprotein lipase (LPL) were significantly elevated at higher concentration. These results suggest that LCM partially stimulates the lipolysis through the induction of HSL and/or ATGL gene expression, resulting in the reduced lipid accumulation and increased glycerol release.

• Journal of Life Science
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• v.24 no.2
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• pp.137-147
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• 2014

Cortex ulmi pumilae, the cortex of Ulmus davidiana var. japonica, has been used in traditional folk medicine for its anti-inflammatory effect. Although its various bioactivities such as anti-inflammatory, anti-microbial, and anti-cancer, have been reported, the anti-adipogenic activity of cortex ulmi pumilae remains unclarified. In the present study, we investigated the effect of cortex ulmi pumilae extract on adipocyte differentiation in 3T3-L1 preadipocytes. Treatment with cortex ulmi pumilae extract significantly reduced the formation of lipid droplets and triglyceride content in a dose-dependent manner; this is associated with an inhibition of the adipogenic transcription factors, CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$). In addition, cortex ulmi pumilae extract treatment during the early stage of adipogenesis showed more efficient anti-adipogenic activity than treatment during other stages of adipogenesis. Cortex ulmi pumilae extract also inhibited cell proliferation and induced G1 arrest of 3T3-L1 cells in the early stage of adipogenesis. This was associated with upregulated expression of Cdk inhibitor p21 and downregulated expression of cyclin E and phospho-Rb, indicating that cortex ulmi pumilae extract blocks mitotic clonal expansion by cell cycle regulation. Taken together, these results suggest that cortex ulmi pumilae extract possesses anti-adipogenic activity through the inhibition of adipocyte differentiation by blocking mitotic clonal expansion.

• Parasites, Hosts and Diseases
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• v.30 no.2
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• pp.113-124
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• 1992

Protective effects of monoclonal antibodies against n. fowleri were comparatively studied. nALB/c mice were treated with two types of monoclonal antibodies, Nf 2 and Nf 154, before and after the infection with N. fowleri. The mortality and mean survival times were then compared. Also, direct effect of the monoclonal antibodies on the N. fewleri trophozoites in vitro were observed. In vitro protective effects of the monoclonal antibodies were also studied in cells infected with N. fowleri. The observed results are summarized as follows: 1. Among mice pretreated twice before the infection with monoclonal antibody Nf 2 (McAb Nf 2), only 15.8% were killed, and the mean survival time was 17, 7 days. This was not much different from the mice pretreated once, as the mortality and mean survival time were 16.7% and 17 days. Those effects were compatible with monoclonal antibody Nf 154 (McAb Nf 154). The above findings contrast with the mortality and mean survival time of the control mice, which were 22.7% and 14.6 days respectively. 2. Mice which received twice the McAb Nf 2 following N. fowleri infection incurred a 19.4% mortality rate with 13.6 days survival time; 17.9% and 15.8 days with on time administration, in contrast to the 25% and 14.6 days in the control group. 3. Marked agglutination effect of McAb Nf 2 or McAb Nf 154 were observed on n. fowkwi, trophogoites. 4. When N, fowleri trophozoites were treated with McAb Nf 2 or McAb Mf 154 combined with comments, the proliferation rate was more significantly suppressed than in that the control, 5. N. fowleri trophozoites treated with McAb Nf 2 or McAb Nf 154 showed an increased number of swollen mitochondria, disfigured cisternal, lipid droplets, and osmiophilic granules in the cytoplasm. 6. A remarkable protective effect of monoclonal antibodies was noticed in CHO cells infected with N. fowleri. More than 90.6% of the infected CHO cells survived, contrasted with 27% of untreated cells. The overall results in this study suggest that N. fewleri treated with monoclonal antibodies against N. fowleri reduce the mortality and prolong the survivial time of the mice when the antibodies are administered before the infection. The protective effect of the monoclonal antibodies is surmised being caused by agglutination of the trophozoites.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1595-1603
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• 2010

The present study was conducted to investigate the effect of dietary grape pomace on lipid metabolism and hepatic morphology of rats fed a high fat diet. The high fat diet contained additional 15% lard to AIN 93-based diet. Male Sprague-Dawley rats were fed experimental diets containing 5% grape pomace for 4 weeks. Serum activities of glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) were not changed by high fat and grape pomace feeding. Serum concentration of triglyceride in rats fed a high fat diet was decreased significantly by dietary grape pomace. Hepatic concentrations of total lipid, total cholesterol and triglyceride were reduced in grape pomace groups with a high fat diet. Fecal concentrations of total cholesterol and triglyceride were increased in grape pomace groups with a high fat diet. The fecal content of coprostanol was not different among the groups. Dietary grape pomace increased the fecal excretion of cholesterol and coprostanone in rats fed a high fat diet. The fecal excretion of bile acid was not affected by feeding grape pomace in rats fed a high fat diet. Light micrographs of liver tissue revealed lipid droplets were increased by a high fat diet, but dietary supplementation of grape pomace tended to alleviate such changes.

• Biomedical Science Letters
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• v.2 no.1
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• pp.71-90
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• 1996

There is considerable current interest in the effect of regular vigorous exercise and in particular endurance-running as a possible measure in improving myocardial function. Some data indicate that the aging heart may actually suffer from vigorous endurance exercise. On the contrary appropriate exercise in aged animals improves myocardial function and aerobic energy metabolism. So far there is relatively little data to indicate that endurance exercise is in fact beneficial in improving myocardial function or damaging to heart of aged animals. The present investigation aimed to study the possible effect of a long range treadmill training program on the heart in aging rats. Male rats aged 3, 10, and 20 months were divided at random into a control (sedentary) and an exercise group. The training group was exercised for 5 days a week on an automated treadmill for 20minutes at 18m/min over a period of 5 months. The exercise regimen of our experiments did not cause any significant changes in the tissues and ultrastructural as com-pared with sedentary age-matched control. Tissues and ultrastructures of myocardial cells in trained group aged 8 months are intact and well organized as well as sedentary control group. Age associated tissue and ultrastructural changes of trained group aged 15 months included : an increase in transformed mitochondria, vacuoles, lysosomes, lipid droplets and early lipofuscin. But the trained heart did not show significant difference in tissue and ultrastructural properties from those of sedentary controls. Endurance-trained group aged 25 months showed significant qualitative tissue and ultrastructural difference as compared with age-matched controls. In addition to those found in 25 months control group, focal necrosis, myofibril fraying, hypercontraction band, seperation of intercalated discs, degenerating nucleus and infiltration of collagenous fiber into myocyte were noted in trained 25 months group. The stereological examination of the mi-crographs disclosed no significant difference in the myoflbril, mitochondrion, sarcotubule and in-terstitium volume density and surface density of mitochondrial cristae and numerical density of mitochondria between trained and control group aged 8 and 15 months. In the trained 25 months group, significant increase in volume density of interstitium, lipofucsin granule were shown as compared to untrained age-matched control. On the other hand, significant decrease in mitochondrion volume density was shown. The myofibril volume density did not differ between trained and control group although trained group showed slight increase. From the data obtained a reduced mitochondria/myofibrils ratio was found in trained rat heart aged 25 months and there was no difference between trained and control rat aged 15 months. But a slight but not significant increase was found in the trained group aged 8 months as compared with same age control group. Such increase in the ratio in young animals is considered to be of great importance to cardiac pumping and adaptability. Whereas such adaptations don't seem to occur in aged heart muscle. This study proposed that repeated endurance exercise do not cause any significant qualitative and quantitative ultrastructural change of heart muscle in young(3months) and adult (10months) suggesting that the heart is able to adapt to the exercise. On the contrary, the repeated endurance exercise stress may actually induce degenerative changes in the aged heart muscle(20months).

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.8-8
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• 2001

Mouse follicles require the addition of gonadotropins (Gns) to complete maturation and ovulation of oocyte and antrum formation of follicles in vitro. However, we tried examination of in vitro growth of mouse pre-antral follicles in medium without Gns and physiological factors. And also, pre-antral follicles were isolated from ovaries by mechanical method. Our present studies were conducted to evaluate on the growth of follicles and intra-follicular oocytes and antrum formation in vitro of mouse pre-antral follicles in two different media. Pre-antral follicles (91-120${\mu}{\textrm}{m}$) were isolated mechanically by fine 30G needles not using enzymes from ovary of 3-6 weeks old female ICR mice. Isolated pre-antral follicles were cultured in 20 ${mu}ell$ droplets of TCM (n=17; follicles: 107.8 $\pm$ 1.58 ${\mu}{\textrm}{m}$; oocytes: 59.9$\pm$1.2 ${\mu}{\textrm}{m}$) or MEM (n=12; follicles: 109.3$\pm$2.53 ${\mu}{\textrm}{m}$; oocytes: 55.4 $\pm$1.6${\mu}{\textrm}{m}$) under mineral oil on the 60mm culture dish. All experimental media was supplemented with 10% FBS but without Gns and/or physiological factors. Pre-antral follicles were individually cultured in drops for 8 days. Antrum formation and growth of pre-antral follicles and intra-follicular oocytes were evaluated using a precalibrated ocular micrometer at $\times$200 magnifications during in vitro culture. Results between different groups were analyzed using combination of Student's t-test and Chi-square, and considered statistically significant when P<0.05. Antrum formation of pre-antral follicles had started in two culture media on day-2. On day-8, antrum formation had occurred in 58.3%(7/12) of pre-antral follicles cultured in MEM, but only in 23.5% (4/17) of those cultured in TCM (P=0.0364). Growth of pre-antral follicles and intra-follicular oocytes were observed on day-4 and -8. On day-4, follicular diameters was similar (P=0.1338) in TCM (119.4$\pm$2.58 ${\mu}{\textrm}{m}$) and MEM (125.4$\pm$4.52 ${\mu}{\textrm}{m}$). However, on day-8, diameters of pre-antral follicles cultured in MEM (168.9$\pm$17.29 ${\mu}{\textrm}{m}$) was significantly (P=0.0248) bigger than that in TCM (126.7$\pm$4.28 ${\mu}{\textrm}{m}$). On day-4 and -8, diameters of intra-follicular oocytes were similar TCM (67.1$\pm$1.3 and 72.4$\pm$0.9${\mu}{\textrm}{m}$) and MEM (65.2$\pm$1.7 and 73.3$\pm$1.5 ${\mu}{\textrm}{m}$), respectively. We can conform that medium not supplemented with Gns and/or physiological factors can be used for in vitro antrum formation and growth of mouse pre-antral follicles and intra-follicular oocytes. In conclusion, MEM supplemented with FBS can be used for growth in vitro of mouse pre-antral follicles isolated mechanically.