1.Neurochemical Identification of Hypothalamic Neurons Expressing c-Fos in response to Hypertonic Saline.
Youngki LEE ; Deokbae PARK ; Ka Young CHANG
Korean Journal of Anatomy 2001;34(1):57-63
Previous studies have shown that hypertonic saline induces c-fos expression in the magnocellular neurons of rat hypothalamus. The present immunohistochemical double-labeling study was undertaken to determine the identification of magnocellular neurons expressing c-Fos in response to osmotic stimulus. Hypertonic saline induced c-Fos-like immunoreactivity (FLI) in various regions of hypothalamus in addition to supraoptic nucleus (SON) and paraventricular nucleus (PVN). FLI was detected in most of oxytocin neurons in the preoptic region and in the accessory nuclei located between the PVN and SON as well as in the SON and PVN. In particular, most of all oxytocin neurons in the accessory nuclei were labeled for c-Fos. There were also many FLI cells that did not show oxytocin and vasopressin immunore-acitivity in their cytoplasm. Relative frequencies of oxytocin and vasopressin neuronal responses showed that much more cells of oxytocin than vasopressin were induced to express c-fos in response to hypertonic saline. These data show that both oxytocin and vasopressin neurons are sensitive to osmotic stimulus and activated via expression of c-Fos by hypertonic saline.
Animals
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Cytoplasm
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Hypothalamus
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Neurons*
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Oxytocin
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Paraventricular Hypothalamic Nucleus
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Rats
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Supraoptic Nucleus
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Vasopressins
2.Improvement of Ergone Production from Mycelial Culture of Polyporus umbellatus.
Wi Young LEE ; Youngki PARK ; Jin Kwon AHN
Mycobiology 2007;35(2):82-86
Ergone,a fungal metabolite derived from ergosterol,was previously isolated and identified from Polyporus umbellatus. Ergone is a major component of P. umbellatus known to have anti-aldosteronic diuretic effect and also displays cytotoxic activities. Most of mushroom's fruit bodies used for test contained less than 10 microg/g of ergone. But P. umbellatus have larger amount of ergone than any other mushrooms. In order to improve the ergone production from the submerged culture of P. umbellatus, several factors including medium composition,culture conditions (temperature and pH) and different combinations of co-cultivation with various mycelia were studied. Among various carbon sources examined,starch proved to be most effective for the production of mycelia. The optimum pH and temperature for a flask culture of P. umbellatus mycelia were found to be 4.5 and 25degrees C,respectively. Under the optimized culture conditions,both the ergone production (86.9 microg/g) and mycelial growth (3.5 g/l) increased when P. umbellatus was cultured with Armillariella mellea. When the optimized conditions were applied,both mycelium and ergone production were significantly enhanced.
Agaricales
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Carbon
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Coculture Techniques
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Diuretics
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Fruit
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Hydrogen-Ion Concentration
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Mycelium
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Polyporus*
3.Erratum: Lutein decreases oxidative stress and inflammation in liver and eyes of guinea pigs fed a hypercholesterolemic diet.
Jung Eun KIM ; Richard M CLARK ; Youngki PARK ; Jiyoung LEE ; Maria Luz FERNANDEZ
Nutrition Research and Practice 2013;7(2):146-146
This article was initially published on Nutrition Research and Practice with mistyped concentration of lutein used in the study.
4.The Relationship between Work Ability and Job Stress Factors in Manufacturing Industries.
Sangbum YE ; Dongmug KANG ; Youngki KIM ; Minjeong SON ; Jongeun KIM ; Somin PARK
Korean Journal of Occupational and Environmental Medicine 2008;20(3):260-271
OBJECTIVE: This study was performed to investigate the association between work ability and job stress factors in three manufacturing industries. METHODS: The data were gathered from 705 workers of 3 manufacturing industries, from August 2007 to January 2008. A structured, self-reported questionnaire was used to access the demographic, socioeconomic and work related characteristics. Work ability and job stress factors were determined using two questionnaires: the work ability index (WAI) of the Finnish Institute of Occupational Health and the Korean Occupational Stress Scale (KOSS), respectively. RESULTS: According to the logistic regression analysis results, WAI was related to job stress factors after adjustment for age, shift work, employment type and exercise. Of the eight subscales, job demand, interpersonal conflict, lack of reward, occupational climate and total score were significantly associated with WAI. In the analysis of each factory, interpersonal conflict, job insecurity and lack of reward were significantly associated with WAI in factory II, and organizational system, lack of reward and total score in factory III, but there was no significant association in factory I. CONCLUSIONS: Job stress factors were significantly associated with WAI in two of the three manufacturing industries. Further and more detailed study needs to be conducted to reduce the job stress and improve the work ability.
Climate
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Employment
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Logistic Models
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Occupational Health
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Questionnaires
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Reward
5.Lutein decreases oxidative stress and inflammation in liver and eyes of guinea pigs fed a hypercholesterolemic diet.
Jung Eun KIM ; Richard M CLARK ; Youngki PARK ; Jiyoung LEE ; Maria Luz FERNANDEZ
Nutrition Research and Practice 2012;6(2):113-119
Guinea pigs were fed a hypercholesterolemic diet (0.25 g/100 g cholesterol) and randomly allocated either to a Control group (n = 9) or to a Lutein (0.1 g/100 g) group (n = 10) for 12 weeks to evaluate oxidative stress and inflammation in both liver and eyes. Malondialdehyde (MDA) concentrations and inflammatory cytokines were measured as well as hepatic nuclear factor-kappaB (NF-kappaB) binding. Lutein concentrations were greater in eyes (P < 0.01) and liver (P < 0.001) in the Lutein group. All guinea pigs had high concentrations of hepatic cholesterol as well as high plasma ALT and AST levels indicative of liver injury. However, the Lutein group had 43% lower hepatic free cholesterol than the Controls (P < 0.05). Hepatic MDA and MDA in the eye were lower in the Lutein compared to the Control group (P < 0.05). Hepatic tumor necrosis factor-alpha was 32% lower in the Lutein group (P < 0.05). Lastly, the Lutein group presented lower NF-kappaB DNA binding activity than the Control group (P < 0.001). These results suggest that in the presence of high cholesterol, lutein exerts both antioxidant and anti-inflammatory effects, which can be explained by attenuated NF-kappaB DNA binding activity. Furthermore, results also suggest that lutein accumulates in the eyes of guinea pigs to protect against oxidative stress.
Animals
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Cholesterol
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Cytokines
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Diet
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DNA
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Eye
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Guinea
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Guinea Pigs
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Inflammation
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Lipid Peroxidation
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Liver
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Lutein
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Malondialdehyde
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NF-kappa B
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Oxidative Stress
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Plasma
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Tumor Necrosis Factor-alpha