• The Korean Journal of Physiology and Pharmacology
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• v.22 no.1
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• pp.91-99
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• 2018

Protein phosphatase 1 (PP1) is involved in various signal transduction mechanisms as an extensive regulator. The PP1 catalytic subunit (PP1c) recognizes and binds to PP1-binding consensus residues (FxxR/KxR/K) in NBCe1-B. Consequently, we focused on identifying the function of the PP1-binding consensus residue, $^{922}FMDRLK^{927}$, in NBCe1-B. Using site-directed mutagenesis and co-immunoprecipitation assays, we revealed that in cases where the residues were substituted (F922A, R925A, and K927A) or deleted (deletion of amino acids 922-927), NBCe1-B mutants inhibited PP1 binding to NBCe1-B. Additionally, by recording the intracellular pH, we found that PP1-binding consensus residues in NBCe1-B were not only critical for NBCe1-B activity, but also relevant to its surface expression level. Therefore, we reported that NBCe1-B, as a substrate of PP1, contains these residues in the C-terminal region and that the direct interaction between NBCe1-B and PP1 is functionally critical in controlling the regulation of the ${HCO_3}^-$ transport. These results suggested that like IRBIT, PP1 was another novel regulator of ${HCO_3}^-$ secretion in several types of epithelia.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.85-96
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• 2003

Normal human skin, constantly challenged by environmental micro-organisms, has an innate ability to fight invading microbes through antimicrobial peptides. These peptides, described in both plant and animal kingdoms are able to inactivate a broad spectrum of micro-organisms. Mammalian defensins constitute one of the most common antimicrobial peptide family. Among the three human beta-defensins hBD1, hBD2 and hBD3 produced in epithelia, only hBD2 and hBD3 are inducible and additionally have been described as expressed by differentiated keratinocytes at site of inflammation and infection. The aims of these studies were to define a cell culture model in which the basal production of hBD could be detected and up-regulated in order to enhance skin auto-protection against micro-organisms. A specific Polymerase Chain Reaction method have been developed for hBD2 and hBD3 mRNA detection in non-differentiated monolayer keratinocytes cell culture. We have been able to demonstrate that in vitro, hBD2 and hBD3 expression in normal human keratinocytes could be detected and enhanced by TNF-alpha and IFN-gamma, in hypercalcic culture conditions. This research opened the possibility of the development of cosmetic active compounds, able to induce the expression of skin natural antibiotic peptides responsible about microflora ecology of the skin.

• Korean Journal of Veterinary Research
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• v.26 no.1
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• pp.125-137
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• 1986

Sprague-Dawley rats received subcutaneous injections of gentamicin sulfate, 50 and 100mg/kg for 3, 7 and 10 days. The hematological and blood chemical values were determined. Kidneys were examined histologically and ultrastructurally. The results obtained were summarized as follows; 1. The serum values of aspartate transaminase, blood urea nitrogen and creatinine in the rats administered gentamicin, 50 and 100mg/kg/day were significantly increased than those in the control. 2. The ratio of kidney weight to body weight was significantly increased in the rats injected gentamicin, 100mg/kg for 10 days than those in the control. 3. The brush borders of proximal convoluted tubules in the kindneys received gentamicin, 50 and 100mg/kg/day were decreased or absent in periodic acid-Schiff staining. 4. The necrosis of proximal convoluted tubules was shown in the rats given gentamicin, 50 and 100mg/kg for 7 and 10 days. 5. The regeneration of the proximal tubular epithelia was observed in the rats treated gentamicin, 100mg/kg for 10 days. 6. The number and size of lysosomes were increased in the proximal convoluted tubules of the rats injected gentamicin, 50mg/kg for 7 days, many of which contained myeloid bodies.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.131-147
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• 1998

A histochemical and ultrastructural study on the epithelia of some selected digestive tracks such as esophagus, crop, intestine of a land snail N. samarangae was carried out during the period of June 1997 to may 1998. The epithelium of digestive tract are simple columnar epithelium and consisted of five types of columnar cells. Type 1 cell which is majority in number has a brush border with microvilli on the free surface of the cell and contains numerous secretory granules supposed to be neutral mucopolysaccharide. Type 2 cell, elongated conical in shape, is rarely found in the epithelium. This cell also has a brush border with microvilli on its free surface and contains well developed rough surfaced endoplasmic reticulum, Golgi bodies, and secretory granules in various electron densities. This cell seems to produce both of acid and neutral mucopolysaccharides. Type 3 cell, which is morphologically similar to the Type 1 cell, has microvilli and cilia on the free surface and exists in group only in the limited regions of the intestine. Type 4 cell, typical goblet cell containing secretory granules in high electron density. Type 5 cell rarely found in the digestive tract. This cell contain inconspicuous materials.

• Toxicological Research
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• v.18 no.4
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• pp.375-384
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• 2002

Repeated-dose toxicity of hyrubicin ID6105, a novel anthrarycline anticancer agent, was investigated in Sprague-Dawley rats. ID6105 was injected intravenously to rats at dose levels of 0.04, 0.2 or 1.0 mg/kg/day for 4 week. As a result, there were no dose-related mortality and specific clinical signs of all animals treated with the drug. However body weight gain of both male and female rats treated with a high dose (l.0 mg/kg/day) of ID6105 significantly decreased compared to control. Interestingly, the numbers of RBC and platelets, and concentration of hemoglobin remarkably increased, while protein synthesis was suppressed, which may be related to the atrophy of spleen, thymus and liver. Moreover there were severe lymphocytic depletion in spleen and thymus as well as decrease in the number of hematopoietic cells in bone marrow. Also, degeneration of cardiac muscles and testicular germinal epithelia were observed. Taken together, it is suggested that Long-term administration of ID6105 at high doses over 0.2 mg/kg/day might cause hematopoietic and male reproductive system injuries, in addition to hepatic dysfunction.

• Korean Journal of Veterinary Service
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• v.22 no.2
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• pp.113-119
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• 1999

The most common cause of death is ostrich chick fading syndrome(OCFS), which is due to bacterial infection during artificial incubation and hatching. Six farmed ostrich chicks aged 3 and 10 days in Chonbuk province, were submitted to Chonbuk Livestock Development and Research Institute for necropsy, Clinically, birds showed hair loss, ocular exudate, lethargy, diarrhea, and subsequently died 3-5 days after onset of clinical signs. Grossly, umbilicus was enlarged. White-yellowish purulent nodules were scattered on the lung and the membrane of air-sac was thickened and had inflamed exudate on the surface in two chicks that died 3 days after hatching. In 10 days-old chick, intestine was shown rodding segmentally. Yolk sac was still retarded and its surface was partially hemorrahgic. The synovial fluid of the leg was yellowish. Microscopically, multifocal purulent exudates were scattered on the lung. Capillary microthrombi in the glomerulus were prominent and tubular epithelia were necrotic. Necrotic hepatocytes were scattered and intestine were congested. Microbiologically, Pseudomonas sp and/or E coli were isolated from air-sac, lung and/or liver. This case suggests that poor hygiene during artificial incubation, hatching or in the first week after hatching may cause high mortality of the ostrich chicks.

• Proceedings of the Korean Society of Toxicology Conference
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• 2005.05a
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• pp.51-82
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• 2005

To compare the pulmonary toxicity between ultrafine colloidal silica particles (UFCSs) and fine colloidal silica particles (FCSs), mice were intratracheally instilled with 3 mg of 14-nm UFCSs and 230-nm FCSs and pathologically examined from 30 mill to 24 hr post-exposure. Histopathologically, lungs exposed to both sizes of particles showed bronchiolar degeneration and necrosis, neutrophilic inflammation in alveoli with alveolar type II cell proliferation and particle-laden alveolar macrophage accumulation. UFCSs, however, induced extensive alveolar hemorrhage compared to FCSs from 30 min onwards. UFCSs also caused more severe bronchiolar epithelial cell necrosis and neutrophil influx in alveoli than FCSs at 12 and 24 hr post-exposure. Laminin positive immunolabellings in basement membranes of bronchioles and alveoli of UFCSs treated animals was weaker than those of FCSs treated animals in all observation times. Electron microscopy demonstrated UFCSs and FCSs on bronchiolar and alveolar wall surface as well as in the cytoplasm of alveolar epithelial cells, alveolar macrophages and neutrophils. Type I alveolar epithelial cell erosion with basement membrane damage in UFCSs treated animals was more severe than those in FCSs treated animals. At 12 and 24 hr post-exposure, bronchiolar epithelia cells in UFCSs treated animals showed more intense vacuolation and necrosis compared to FCSs treated animals. These findings suggest that UFCSs has greater ability to induce lung inflammation and tissue damages than FCSs.

• Journal of Embryo Transfer
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• v.27 no.4
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• pp.211-221
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• 2012

The process of embryo implantation requires physical contact and physiological communication between the conceptus trophectoderm and the maternal uterine endometrium. During the peri-implantation period in pigs, the conceptus undergoes significant morphological changes and secretes estrogens, the signal for maternal recognition of pregnancy. Estrogens secreted from the conceptus act on uterine epithelia to redirect $PGF_2{\alpha}$, luteolysin, secretion from the uterine vasculature to the uterine lumen to prevent luteolysis as well as to induce expression of endometrial genes that support implantation and conceptus development. In addition, conceptuses secrete cytokines, interferons, growth factors, and proteases, and in response to these signals, the uterine endometrium produces hormones, protease inhibitors, growth factors, transport proteins, adhesion molecules, lipid molecules, and calcium regulatory molecules. Coordinated interactions of these factors derived from the conceptus and the uterus play important roles in the process of implantation in pigs. To better understand mechanism of implantation process in pigs, this review provides information on signaling molecules at the conceptus-uterine interface during early pregnancy, including recently reported data reported.

• Journal of Life Science
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• v.11 no.3
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• pp.259-265
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• 2001

Mercury vapor inhalation-induced acute respiratory failure(ARF) has been reported to be fatal. This study was designed to observe the possible mechanism of inhaled mercury vapor poisoning in the respiratory system. Sixty percent of rats(12/20) exposed to mercury vapor were dead within 72 hours of exposure whereas all the rats(20/20) exposed to mercury vapor combined with dithiothreitol(DTT) vapor survived. The histological observation showed that ARF was a direct cause of the death induced by mercury vapor inhalation, which was significantly circumvented by DTT vapor. Cyclic AMP mediated chloride secretion was inhibited by luminal side but not serosal side sulfhydryl blocking agents (Hf$^{2+}$ $\rho$-chloromercuribenzoic acid or $\rho$-chloromercuriphenyl sulfonic acid) in a dose-dependent manner in a primary cultured rat airway monolayer. The inhibitory component of cAMP induced chloride secretion was completely restored by luminal side DTT(0.5mM). these results suggest that the oxidized form(Hg$^{2+}$) of mercury vapor(Hg0) contribute to ARF and subsequent death. The finding is important as it can provide important information regarding emergency manipulation of ARF patients suffering from by mercury vapor poisoning.ing.

• Korean Journal of Veterinary Research
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• v.44 no.3
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• pp.329-334
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• 2004

Ischemia/reperfusion(I/R) injury of the rat testis causes germ cell death and infiltration of inflammatory cells. To investigate the mechanism of germ cell death in torsion of the rat testis, apoptosis and macrophage activation were studied using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling(TUNEL) method and immunohistochemistry in the testes of Sprague-Dawley rats subjected to 1.5 h of ischemia, followed by 0, 1, 3, 6, 12, 24, 48 and 96 h of reperfusion. Apoptotic, TUNEL-positive cells were found at the base of the seminiferous epithelia after I/R. TUNEL-positive cells were significantly increased 6 h after repair of the torsion, and there was a significant peak in apoptosis 24 h after reperfusion, as compared with normal or sham-operated controls. In contrast, histological evidence of germ cell necrosis in the seminiferous tubules was first visible 24 h after reperfusion. In the testis of sham-operated rats, ED2-positive resident macrophages were found diffusely in the interstitial space, while ED1-positive monocyte-like macrophages were rarely found. After I/R, ED1-positive cells were significantly increased beginning 12 h after reperfusion, while ED2-positive immunoreactivity did not change during the experimental period. Together, the results of this study confirmed that increased numbers of ED1-positive macrophages, but not resident ED2-positive macrophages, infiltrated the interstitial space surrounding damaged tubules and induced germcell death.