• The Korean Journal of Physiology and Pharmacology
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• 제26권6호
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• pp.479-499
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• 2022

The lack of a clonal renin-secreting cell line has greatly hindered the investigation of the regulatory mechanisms of renin secretion at the cellular, biochemical, and molecular levels. In the present study, we investigated whether it was possible to induce phenotypic switching of the renin-expressing clonal cell line As4.1 from constitutive inactive renin secretion to regulated active renin secretion. When grown to postconfluence for at least two days in media containing fetal bovine serum or insulin-like growth factor-1, the formation of cell-cell contacts via N-cadherin triggered downstream cellular signaling cascades and activated smooth muscle-specific genes, culminating in phenotypic switching to a regulated active renin secretion phenotype, including responding to the key stimuli of active renin secretion. With the use of phenotype-switched As4.1 cells, we provide the first evidence that active renin secretion via exocytosis is regulated by phosphorylation/dephosphorylation of the 20 kDa myosin light chain. The molecular mechanism of phenotypic switching in As4.1 cells described here could serve as a working model for full phenotypic modulation of other secretory cell lines with incomplete phenotypes.

• Biomedical Science Letters
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• 제8권3호
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• pp.195-202
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• 2002

Osteoarthritis (OA), the most common form of arthritis, involves the destabilization of the normal balance between the degradation and the synthesis of articular cartilage and subchondral bone within a joint. As articular cartilage degrades over time, its smooth surface roughens and bone-against-bone contact ensues, producing the inflammation response symptomatic of this 'wear and tear' disease. Although a variety of genetic, developmental, metabolic, and traumatic factors may initiate the development of osteoarthritis, its symptoms (joint pain, stiffness, and curtailed function) typically evolve slowly, and patients experience periods of relative calm alternation with episodes of inflammation and pain. Rheumatoid arthritis (RA), an autoimmune disease of unknown etiology characterized by chronic synovitis and cartilage destruction, affect 1% of the total population. Cartilage is a specialized connective tissue in which the chondrocytes occupy only 5% of the volume. Cartilage is particularly rich in extracellular matrix, with matrix making up 90% of the dry weight of the tissue chondrocytes have cell processes that extend a short distance into the matrix, but do not touch other cells thus in cartilage, cell-matrix interactions are essential for the maintenance of the extracellular matrix. In this study, subtractive hybridization method was utilized to detect genes differentially expressed in chondrocytes treated with methylprednisolone. We have isolated 57 genes that expressed differentially in the chondreocytes by methylprednisolone. 13 clones of them were analyzed with sequencing and their homologies were searched. 8 cDNAS included KIAA 0368, upregulated during skeletal muscle growth 5 (usmg 5), ribosomal protein S 18 (RPS 18), skeletal muscle ryanodine receptor, radial spoke protein 3 (RSP 3), ribosomal protein QM, ribosomal protein L37a (RPL37A), cytochrome coxidase subunit VIII (COX8).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권6호
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• pp.533-537
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• 2010

Sialadenoma papilliferum (SP) is a rare benign neoplasm that normally arises from the minor salivary glands, particularly in the palate. SP is normally encountered in older men with an exophytic papillary surface growth. In the present study, an SP of the hard palate of a 69-year-old woman was examined immunohistochemically. Myoepithelial cell markers, such as S-100, smooth muscle actin and vimentin, were observed in the basal or luminal layer of tumor cells, indicating that myoepithelial cells participate in the pathogenesis of SP. In addition, cytokeratin 7 was also strongly detected in the tumor cells, suggesting that excretory ductal epithelial cells have a role in its histogenesis. A review of the literature of immunohistochemical studies on SP showed that the expression and co-expression of cytokeratins and myoepithelial cell markers have been reported in tumor cells. These results suggested that excretory duct cells and myoepithelial cells participate in the pathogenesis of SP.

• The Korean Journal of Physiology and Pharmacology
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• 제15권1호
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• pp.37-41
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• 2011

Interstitial cells of Cajal (ICC) evoke pacemaker activities in many tissues. The purpose of this study was to investigate the relationship between interstitial cell and pacemaker activity in the human ureter through the recording of spontaneous contractions. Spontaneous contractions of eight circular and longitudinal smooth muscle strips of the human ureter to acetylcholine (ACh) and/or norepinephrine (NE) were observed. Human ureteral strips were divided into proximal and distal groups, and each group was subdivided into circular and longitudinal groups. The proximal group showed spontaneous activities of 3~4 times within 5 minutes in the longitudinal group. ACh ($10^{-4}\;M$) augmented the frequency of the spontaneous contractions. The cumulative application of NE also augmented the frequency in a dose-dependent manner. The effects of NE application were inhibited by concomitant application of $10^{-5}\;M$ glibenclamide. Receptor tyrosine kinase (c-kit) staining revealed abundant ICCs only in proximal tissues. Therefore, spontaneous contractions of the human ureter might be modulated by ICC in the proximal region, and the actions might be related with the activation of cholinergic and/or adrenergic system mediated by a glibenclamide-sensitive pathway.

• Nutrition Research and Practice
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• 제4권5호
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• pp.369-374
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• 2010

Grape is one of the most popular and widely cultivated fruits in the world. Although grape skin and seeds are waste product of the winery and grape juice industry, these wastes contain large amounts of phytochemicals such as flavonoids, phenolic acids, and anthocyanidins, which play an important role as chemopreventive and anticancer agents. We evaluated efficacies of grape skin and seeds on hepatic injury induced by dimethylnitrosamine (DMN) in rats. Treatment with DMN significantly increased levels of serum alanine transaminase, aspartate transaminase, alkaline phosphatase, and bilirubin. Diet supplementation with grape skin or seeds (10% daily for 4 weeks) prevented these elevations. The grape skin and seeds also restored serum albumin and total protein levels, and reduced the hepatic level of hydroxyproline and malondialdehyde. Furthermore, grape skin and seeds reduced DMN-induced collagen accumulation, as estimated by histological analysis of liver tissue stained with Sirius red. Grape skin and seeds also reduced hepatic stellate cell activation, as assessed by ${\alpha}$-smooth muscle actin staining. In conclusion, grape skin and seeds exhibited in vivo hepatoprotective and antifibrogenic effects against DMN-induced liver injury, suggesting that grape skin and seeds may be useful in preventing the development of hepatic fibrosis.

• Journal of Veterinary Clinics
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• 제23권2호
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• pp.194-196
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• 2006

A leiomyosarcoma that occurred in the right kidney with hepatic metastasis of a 15-year-old intact female Asian water buffalo (Bubalus arnee) in a zoo, Republic of Korea. The animal showed no clinical signs. Grossly, a firm and white mass (6.0 x- 5.0- x 4.0 cm) was observed in the renal capsule and multiple firm white nodules, measuring 1.0-2.5 cm, were present on the surface of the liver. Microscopically, tumor cells were spindle-shaped, the cell density was high, and complex fasciculated tumor cells showing longitudinal and transverse cross-sections were observed. Tumor cell nuclei was ordinarily cigar shaped and had rounded blunt ends. Immunohistochemically, tumor cells reacted intensely with anti-smooth muscle actin antibody. This is the first case report of a renal leiomyosarcoma with hepatic metastasis in a Asian water buffalo.

• Journal of Veterinary Clinics
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• 제33권1호
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• pp.43-47
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• 2016

A 7-year-old castrated male Schnauzer was presented with melena and inappetence. Laboratory examination revealed mild anemia. Abdominal ultrasonography showed abnormal enlargement of intestinal segment and a oval mass with soft tissue density. After surgical resection of the enlarged intestine including the mass, histopathologic examination showed that the mass was tentatively diagnosed as synchronous occurrence of gland cell- and mesenchymal cell-origin tumors. Subsequently, immunohistochemistry showed positivity to cytokeratin AE1/AE3 in the gland cells and positivity to ${\alpha}-smooth$ muscle-specific actin, but negative expression of c-Kit, suggesting the co-existence of adenocarcinoma and leiomyosarcoma. Follow-up examination after 3-year of the surgery confirmed that the dog remained healthy and did not show recurrence of the tumors.

• Toxicological Research
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• 제35권2호
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• pp.201-207
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• 2019

Nanoxel-$PM^{TM}$ (Nanoxel) is a docetaxel-loaded methoxy-poly(ethylene glycol)-block-poly(D,L-lactide) (mPEG-PDLLA). This newly developed and marketed nanoformulation exhibits an improved pharmacokinetic profile, efficacy, and safety. Although the safety of Nanoxel to docetaxel as well as its bioequivalence must be clinically confirmed, all biological activities have not been examined in in vitro or in vivo studies. Here, the toxicity in a cultured cell system and the effects on blood cells were tested with Nanoxel and docetaxel. The in vitro cytotoxicity of Nanoxel was found to be comparable to or slightly lower than that of docetaxel depending on the concentrations tested or the cell types. Neither docetaxel nor Nanoxel induced erythrocytes hemolysis and produced reactive oxygen species up to $100{\mu}M$. However, Nanoxel was able to enhance the aggregatory response of platelets to collagen, whereas docetaxel attenuated such aggregation in a range of $50-100{\mu}M$, while thrombin-induced aggregation was not affected by either of them. Docetaxel or Nanoxel did not alter basal level of $Ca^{2+}$ and 5-hydroxytryptamine-evoked $Ca^{2+}$ transient in vascular smooth muscle cells. These results suggest that the mPEG-PDLLA micellar formulation alters the toxicological properties of docetaxel, and that extra cautions are needed when evaluating the safety of nanomedicine.

• BMB Reports
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• 제57권3호
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• pp.143-148
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• 2024

Pulmonary fibrosis is a serious lung disease that occurs predominantly in men. Genistein is an important natural soybean-derived phytoestrogen that affects various biological functions, such as cell migration and fibrosis. However, the antifibrotic effects of genistein on pulmonary fibrosis are largely unknown. The antifibrotic effects of genistein were evaluated using in vitro and in vivo models of lung fibrosis. Proteomic data were analyzed using nano-LC-ESI-MS/MS. Genistein significantly reduced transforming growth factor (TGF)-β1-induced expression of collagen type I and α-smooth muscle actin (SMA) in MRC-5 cells and primary fibroblasts from patients with idiopathic pulmonary fibrosis (IPF). Genistein also reduced TGF-β1-induced expression of p-Smad2/3 and p-p38 MAPK in fibroblast models. Comprehensive protein analysis confirmed that genistein exerted an anti-fibrotic effect by regulating various molecular mechanisms, such as unfolded protein response, epithelial mesenchymal transition (EMT), mammalian target of rapamycin complex 1 (mTORC1) signaling, cell death, and several metabolic pathways. Genistein was also found to decrease hydroxyproline levels in the lungs of BLM-treated mice. Genistein exerted an anti-fibrotic effect by preventing fibroblast activation, suggesting that genistein could be developed as a pharmacological agent for the prevention and treatment of pulmonary fibrosis.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.78-78
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• 2003

Adult stem cells can make identical copies of themselves for long periods of time. They also give rise to many differentiated mature cell types that have characteristic morphology and specialized function. Human adult stem cells are the attractive raw materials for the cell/tissue therapy, however, it is not easy to get from the adult tissues. In the present study, we tried to isolate a cell population derived from human umbilical cord vein which has been discarded after birth. The cells were isolated after treatment of the umbilical vein with collagenase or trypsin. After 3 days of culture, two kinds of cell populations were found consisting of adherent cells with endothelial cell-like and fibroblast-like morphology, respectively. When these cells were subcultured 12 times over a period of 3 months, almost cells appeared uniformly to exhibit fibroblastoid morphology which was different from that of mesenchymal stem cells obtained from human bone marrow The results of RT-PCR analyses showed distinct expression of BMP-4, oct-4, and SCF genes but not of GATA, PAX-6 and Brachyury genes. On immunohistochemical staining, the cells were negative for the von Willebrand factor(vWF), alpha-smooth muscle actin and placental alkaline phosphatase. From these observations, it is suggested that stem-like cells might be present in human umbilical cord vein.