• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.535-538
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• 2000

Human leptin is a 16 kDa (146 amino acids) protein secreted from adipocytes and influences body weight homeostasis. In this report, active human leptin was successfully produced in the culture medium of Bacillus subtilis. After simple purification steps consisting of ammonium sulfate precipitation and anion-exchange column chromatography, 2.3 mg of leptin with a purity of greater than 95% was obtained from the 0.5 L culture with the recovery yield of 54.9%. The purified leptin showed the correct folding structure with one disulfide bond.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.3-4
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• 2003

Body weight is maintained at a relatively constant level over days and months despite variability in food intake and physical activity. To achieve energy homeostasis, the hypothalamus receives information related to energy surplus or shortage from the periphery and controls food intake and energy expenditure. Leptin, an adipocyte derived hormone, is a principal mediator that signals the brain about the stored energy status. Increased leptin signaling in the brain prevents excess energy stores by suppressing food intake and increasing energy expenditure. In addition, insulin and nutrients themselves, such as glucose and free fatty acids, also regulate food intake.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.16 no.1
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• pp.17-21
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• 2013

The gut mucosal barrier plays an important role in maintaining a delicate immune homeostasis. The pathogenesis of inflammatory bowel disease (IBD) is considered to involve a defective mucosal immunity along with a genetic predisposition. Recent views have suggested an excessive response to components of the gut microbiota in IBD. A condition of "dysbiosis", with alterations of the gut microbial composition, has been observed in patients with IBD. In this article, the author review recent studies of gut microbiota in IBD, particularly the importance of the gut microbiota in the pathogenesis of pediatric IBD.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.04a
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• pp.113-130
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• 2003

1. We have established a model system to study sodium chloride, an environmental factor, induced gene regulations. 2. ${\alpha}$ENaC, cox-2, and c-fos genes are regulated by sodium chloride at mRNA level as well as at protein level. 3. Regulation of ${\alpha}$ENaC requires syntheses of new protein(s). 4. COX-2 may have a important role for homeostasis in hypertonic situation.

• The Journal of Korean Physical Therapy
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• v.12 no.3
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• pp.369-377
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• 2000

Hot spring water is petrifaction water and mixed with animals and plants disintegrated water in the underground. The ingredient are complicated and abundant. The contained element is used to facilitate the function of human body. activate the human structure movement. discharge waste material due to increase circulation and metabolism, also it can remain the homeostasis. We can not find research for spa therapy in our country. We use to drink and bath in the hot spring water bue don't have rehabilitation facilities

• Molecules and Cells
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• v.28 no.2
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• pp.81-85
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• 2009

$Na^+-H^+$ exchanger (NHE) is the main acid extruder in cardiac myocytes. We review the experimental findings of ion-dependency of NHE activity, and the mathematical modeling developed so far. In spite of extensive investigation, many unsolved questions still remain. We consider that the precise description of NHE activity with mathematical models elucidates the roles of NHE in maintaining ionic homeostasis, especially under pathophysiological conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.510-522
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• 2008

Our earlier studies showed that estrogen was involved in the regulation of fluid reabsorption in adult mouse efferent ductules (ED), through estrogen receptor (ER) ${\alpha}$ and $ER{\beta}$ by modulating gene expression of epithelial genes involved in ion homeostasis. However, little is known about the importance of $ER{\alpha}$ in the ED during postnatal development. Based on previous findings, we hypothesized that there should be a difference in the expression of epithelial ion transporters and anion producers in the ED of postnatal wild type (WT) and estrogen receptor ${\alpha}$ knockout (${\alpha}ERKO$) mice. Using absolute, comparative and semi-quantitative RT-PCR along with immunohistochemistry, we looked at expression levels of several genes in the ED across postnatal development. The presence of estrogen in the testicular fluid was indirectly ascertained by immunohistochemical detection of the P450 aromatase in the testis. There was no immunohistochemically detectable difference in the expression of P450 aromatase in the testes and ER${\beta}$ in the ED of WT and ${\alpha}$ERKO mice. ER${\alpha}$ was only detected in the ED of WT mice. The absence of ER${\alpha}$ in the ED of postnatally developing mice resulted in differential expression of mRNAs and/or proteins for carbonic anhydrase II, $Na^+/H^+$ exchanger 3, down-regulated in adenoma, cystic fibrosis transmembrane regulator, and $Na^+/K^+$ ATPase ${\alpha}$. Our data indicate that the absence of ER${\alpha}$ resulted in altered expression of an epithelial ion producer and transporters during postnatal development of mice. We conclude that the presence of ER${\alpha}$is important for regulation of the ED function during the prepubertal developmental and postpubertal period.

• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.319-325
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• 2001

Several recent studies demonstrate that cAMP accumulation evokes marked changes in magnesium ($Mg^{2+}$) homeostasis. The goal of this study was to investigate the effect of melatonin, the principal hormone of the vertebral pineal gland, on $Mg^{2+}$ regulation in perfused guinea pig hearts. We hypothesized that melationin would regulate $Mg^{2+}$ efflux induced by adrenergic drugs and cAMP analogues because melatonin inhibites adneylate cyclase (AC) and phospholipase C(PLC) in the hearts. The $Mg^{2+}$ content in the perfusate was significantly higher in the presence than in the absence of melatonin. The addition of forskolin, isoproterenol or dimaprit to perfused hearts induced a marked $Mg^{2+}$ efflux. These effluxes were not inhibited by melatonin. The $Mg^{2+}$ efflux could also be induced by phenylephrine, a ${\alpha}_1$-adrenoceptor agonist. This phenylephrine-induced $Mg^{2+}$ efflux was inhibited by melatonin. In addition, the phenylephrine-induced $Mg^{2+}$ efflux was potentiated by PMA, a protein kinase C(PKC) activator. This $Mg^{2+}$ efflux was inhibited by melatonin. In conclusion, these data suggest that melatonin regulates $Mg^{2+}$ homeostasis and the inhibitory effect of melatonin on ${\alpha}_1$-adrenoceptor-stimulated $Mg^{2+}$ efflux may occur through an inhibition of PLC pathway in perfused guinea pig hearts.

• Clinical and Experimental Pediatrics
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• v.63 no.7
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• pp.239-250
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• 2020

The novel coronavirus disease 2019 (COVID-19) is spreading globally. Although its etiologic agent is discovered as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), there are many unsolved issues in COVID-19 and other infectious diseases. The causes of different clinical phenotypes and incubation periods among individuals, species specificity, and cytokine storm with lymphopenia as well as the mechanism of damage to organ cells are unknown. It has been suggested that in viral pneumonia, virus itself is not a direct cause of acute lung injury; rather, aberrant immune reactions of the host to the insults from viral infection are responsible. According to its epidemiological and clinical characteristics, SARS-CoV-2 may be a virus with low virulence in nature that has adapted to the human species. Current immunological concepts have limited ability to explain such unsolved issues, and a presumed immunopathogenesis of COVID-19 is presented under the protein-homeostasis-system hypothesis. Every disease, including COVID-19, has etiological substances controlled by the host immune system according to size and biochemical properties. Patients with severe pneumonia caused by SARS-CoV-2 show more severe hypercytokinemia with corresponding lymphocytopenia than patients with mild pneumonia; thus, early immunomodulator treatment, including corticosteroids, has been considered. However, current guidelines recommend their use only for patients with advanced pneumonia or acute respiratory distress syndrome. Since the immunopathogenesis of pneumonia may be the same for all patients regardless of age or severity and the critical immune-mediated lung injury may begin in the early stage of the disease, early immunomodulator treatment, including corticosteroids and intravenous immunoglobulin, can help reduce morbidity and possibly mortality rates of older patients with underlying conditions.

• Nutrition Research and Practice
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• v.8 no.4
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• pp.469-475
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• 2014

BACKGROUND/OBJECTIVE: The goal of the present study was to investigate the effects of moderate caloric restriction on ${\beta}$-cell function and insulin sensitivity in middle-aged obese Korean women. SUBJECTS/METHODS: Fifty-seven obese pre-menopausal Korean women participated in a 12-week calorie restriction program. Data on total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), and fasting serum levels of glucose, insulin, C-peptide, blood pressure, leptin and anthropometrics were collected. A dietary intake assessment was based on three days of food recording. Additionally, ${\beta}$-cell function [homeostasis model assessment of ${\beta}$-cell (HOMA-${\beta}$), insulinogenic index (ISI), C-peptide:glucose ratio, and area under curve insulin/glucose ($AUC_{ins/glu}$)] and insulin sensitivity [homeostasis model assessment for insulin resistance (HOMA-IR), Quantitative insulin-sensitivity check index (QUICKI) and Matsuda index (MI)] were recorded. RESULTS: When calories were reduced by an average of 422 kcal/day for 12 weeks, BMI (-2.7%), body fat mass (-10.2%), and waist circumference (-5%) all decreased significantly (P < 0.05). After calorie restriction, weight, body fat percentage, hip circumference, BP, TC, HDL-C, LDL-C, plasma glucose at fasting, insulin at fasting and 120 min, $AUC_{glu}$ and the insulin area under the curve all decreased significantly (all P < 0.05), while insulin sensitivity (HOMA-IR, QUICKI and Matsuda index) measured by OGTT improved significantly (P < 0.01). CONCLUSIONS: Moderate weight loss due to caloric restriction with reduction in insulin resistance improves glucose tolerance and insulin sensitivity in middle-aged obese women and thereby may help prevent the development of type 2 diabetes mellitus.