• Journal of Embryo Transfer
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• v.19 no.2
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• pp.89-99
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• 2004

Stretch-activated channels (SACs) responds to membrane stress with changes in open probability (Po). They play essential roles in regulation of cell volume and differentiation, vascular tone, and in hormonal secretion. SACs highly present in Xenopus oocytes and Ascidian oocytes are suggested to be involved in the regulation of pH and fluid transport to balance the osmotic pressure, but remain unclear in mammanlian oocytes. This study was investigated to find the presence of SACs in hamster oocytes and to examine their electrophysiological properties. To infer a role of SAC in relation to the development of early stage, we followed up to the stage of two-cell zygote with patch clamp techniques. Single channels were elicited by negative pressure (lower than ­15 cm$H_2O$). Interestingly, SACs were dependent on permeable cations such as $Na^+$ or $K^+$. As permeable cation removed from both sides across the membrane, SAC activity completely disappeared. When permeable cations present only in intracellular compartment, outward currents appeared at positive potentials. In contrast to this, inward currents occurred only at the negative voltage when permeable cation absent in cell interior. These result suggests that SAC carry cations through the nonselective cation channel (NSC channel). Taken together, we found that stretch activated channels present in hamster oocyte and the channel may carry cations through NSC channels. This stretch activated-NSC channels may play physiological role(s) in oocyte growth, maturation, fertilization and embryogenesis in fertilized oocytes to two-cell zygotes of hamster.

• The korean journal of orthodontics
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• v.28 no.4 s.69
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• pp.611-626
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• 1998

Cytokines are intercellular peptide mediators that regulate homeostasis and host defense reactions in living body. Of the diversity of cytokines in terms of biological accomplishment, interleukin $1-{\beta}$($IL-1{\beta}$) and tumor necrosis factor(TNF) are the most conspicuous cytokines with a wide variety of effects on cells involved in inflammatory and immune responses, and likely to be involved in the inflammatory pathogenesis of oral tissue as well. The present study was designed to explicate the role of $IL-1{\beta}$ on inflammatory revelation of oral tissues in mice biochemically. In the Induced arthritis by injection of 10${\mu}g$ LPS shown the relaese of 0.93 ${\mu}g$ $IL-1{\beta}$/joint with a peak at at 4-5 h. and diminished at 24t and the release of $TNF_{\alpha}$ of 1.25 ${\mu}g$/joint with a peak at 2-3h and diminished at 6h. After injection of th $IL-1{\beta}$ into the joint, the mumber of leucocytes proliferated with a peak at 4-5h and diminished at 36h and the loss of proteoglycan showed with maximum at 15-30h. After injection of $IL-1{\beta}$ into the oral tissue, cycloosygenase metabolites ($PGE_2$) accumulated in the oral tissue with dose dependant. These elucidated $IL-1{\beta}$ to be inflammatory mediator in the early phase of its pathogenesis. Intraoral injection of recombinant $IL-1{\beta}$ induced the proliferation of leukocytes in situ. $IL-1{\beta}$ took an pertinent part in the development of inflammation and the succession of cellular infiltration. The results exemplify that $IL-1{\beta}$ plays a significant role in mediating inflammatory response induced by LPS in oral tissue, the inflammatory response is regulated by $IL-1{\beta}$ at an acute phase of pathogenesis.

• Korean Journal of Veterinary Research
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• v.9 no.1
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• pp.23-62
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• 1969

Throughout the studies the following experimental results were obtained and are summarized: 1. Multiplication of agents in primary cell cultures of both GF classical and CR-64 acute strain of Marek's disease infected chicken kidneys was accompanied by the formation of distinct transformed cell foci. This characteristic nature of cell transformation was passaged regularly by addition of dispersed cell from infected cultures to normal chicken kidney cell cultures, and also transferred was the nature of cell transformation to normal chick-embryo liver and neuroglial cell cultures. No cytopathic changes were noticed in inoculated chick-embryo fibroblast cultures. 2. The same cytopathic effects were noticed in normal kidney cell monolayers after the inoculation of whole blood and huffy coat cells derived from both forms of Marek's disease infected chickens. In these cases, however, the number of transformed cell foci appearing was far less than that of uninoculated monolayers prepared directly from the kidneys of Marek's disease infected chickens. 3. The change in cell culture IS regarded as a specific cell transformation focus induced by an oncogenic virus rather than it plaque in slowly progressing cytopathic effect by non-oncogenic viruses, and it is quite similar to RSV focus in chick-embryo fibroblasts in many respects. 4. The infective agent (cell transformable) were extremely cell-associated and could not be separated in an infective state from cells under the experimental conditions. 5. The focus assay of these agents was valid as shown by the high degree of linear correlation (r=0.97 and 0.99) between the relative infected cell concentration (in inoculum) and the transformed cell foci counted. 6. No differences were observed between the GF classical strain and the CR-64 acute strain of Marek's disease as far as cell culture behavior. 7. Characterization of the isolates by physical and chemical treatments, development of internuclear inclusions in Infected cells, and nucleic acid typing by differential stainings and cytochemical treatments indicated that the natures of these cell transformation agents closely resemble to those described fer the group B herpes viruses. 8. Susceptible chicks inoculated with infected kidney tissue culture cells developed specific lesions of Marek's disease, and in a case of prolonged observation after inoculation (5 weeks) the birds developed clinical symptoms and gross lesions of Marek's disease. Kidney cell cultures prepared from those inoculated birds and sacrificed showed a superior recovery of cell transformation property by formation of distinct foci. 9. Electron microscopic study of infected kidney culture cells (GF agent) by negative staining technique revealed virus particles furnishing the properties of herpes viruses. The particle was measured about $100m{\mu}$ and, so far, no herpes virus envelop has been seen from these preparations. 10. No relationship of both isolates to avian leukosis/sarcoma group viruses and PPLO was observed.

• Journal of Chest Surgery
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• v.30 no.4
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• pp.363-372
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• 1997

One hundred forty-four patients underwent operation for coarctation of the aorta at Seoul National University Children's Hospital between June 1986 and Decembsr 1995. Age ranged 0.1 to 191 months. Of these 78.5%(113) were infants. We classified the patients in terms of the anatomic location of coarctatiln and the associatCd anomalies(I[401= primary coarctation, 11(741=isthmic hypoplasia, lIIf30)=tubular hypoplasia involving transverse arch, Ar63 =with ventricular septal defect, B(28)=with other major cardiac defects). Subcalvian flap coarctoplasty(60), resection & anastomosis(44), extended aortoplasty(26), and onlay patch(14) were used as surgical methods. Overall operative mortality was 16.0(23/144)%. The hospital mortality was signific'antly higher in patheints with type 111, subtype B, younger age(under 3 months), extended aortoplasty(p(0.01). However, one-stage total repair in patients with subtype A or B were not found to be a predictor of hospital death. Restenosis had occured in 18 patients among 121 survivals(14. 9%). The mean follow-up period was 29.1 $\pm$28.8(0~129.2) months. Preoperative, immediate postoperative(within 3 months after operation) and postoperative(later than 6 months after operation) echocardiographic data on the dimensions of ascending aorta(AA), transverse arch(TA), an4 aortic isthmus(Al) were available in 77 patients(I=20, ll=42, 111= 15). Preoperative and postoperative aortic isthmus(All) and tra sverse arch indices(TAI), defined as TAIAA & AIIAA respectively, were compared. Immediate postoperative All in type 1, II and TAI in type 111 were significantly smaller in stenotic than non-stenotic group suggesting incomplete relieves of stenotic segment Younger age, subclavian coarctoplasty in patient under 3 months of age were round to be the risk factors for restenosis in this series. In conclusion, We found that aortic arch index and transverse arch index can be a useful tool to figure out the anatomic and clinical characteristics of the patients with aortic coarctation, and that anatomy, associated anomalies, age, and surgical methods may influence the surgical outcome of the coarctation repair.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1377-1382
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• 2009

Purpose:The gonadotropin-releasing hormone (GnRH) test results of girls with precocious puberty were analyzed to determine whether this test can efficiently and clearly differentiate between central precocious puberty (CPP) and other disorders. Methods:Clinical and laboratory data of 54 girls with precocious pubertal signs were reviewed. Intravenous GnRH test was performed with blood samples obtained at 0, 30, 60, and 90 minutes. A peak luteinizing hormone (LH) level of ${\geq}5.0IU/L$ was indicative of CPP. Results:Of the 40 girls with CPP, 36 (90.0%), 3 (7.5%), and 1 (2.5%) showed peak LH levels at 30, 60, and 90 minutes, respectively. A percentage of girls whose peak LH ${\geq}5.0IU/L$ up to 30, 60, and 90 minutes was 92.5%, 100%, and 100%, respectively. The peak LH/follicle stimulating hormone (FSH) ratio of girls with CPP was 0.89${\pm}$0.49 and was <1 in 16 of the 40 girls (40.0%). Girls with peak LH/FSH ratio of >1.0 showed higher chronological age (CA) ($8.3{\pm}0.6$ vs. $7.7{\pm}1.0$ years, P=0.033), bone age (BA) ($10.9{\pm}0.8$ vs. $9.7{\pm}1.1$ years, P=0.001), and BA-CA difference ($2.6{\pm}0.7$ vs. $2.0{\pm}0.7$ years, P=0.009) than those of girls with peak LH/FSH ratio of ${\leq}1.0$. Higher percentage of girls with peak LH/FSH ratio of >1.0 showed advanced breast development (${\geq}TannerIII$) (93.7% vs. 41.7%, P=0.001). Conclusion:LH levels after 30 and 60 minutes of intravenous GnRH administration are the most useful for diagnosing CPP in girls.

• The Korean Journal of Nuclear Medicine
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• v.37 no.3
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• pp.190-198
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• 2003

Purpose: To evaluate radiation sensitivity of dendritic cells in comparison with lymphocytes. Materials and methods: T lymphocytes captured from peripheral blood were irradiated by 0 Gy, 10 Gy, 30 Gy. Apoptosis was measured by flowcytometry for staining of Annexin V 4 hours after irradiation. Immature and mature dendritic cells processed from blood hematopoietic stem cell were irradiated by 0 Gy, 10 Gy, 30 Gy, 100 Gy respectively and apoptosis was measured by flowcytometry with time difference as 4h, 24h and 48h after irradiation. Morphometric analysis by percent nucleus was measured in three cell groups, also. Results: Lymphocytes showed radiation sensitivity by increasing apoptotic fraction according to radiation dose. However, both mature and immature dendritic cells showed consistent fraction of apoptosis in spite of increasing radiation dose. Percent nucleus ratio is significantly higher in lymphocytes than that of mature or immature dendritic cells. Stimulation of T-cell by dendritic cells was not changed after irradiation. Conclusion: Dendritic cells showed radioresistance which was associated with small size of nucleus in comparison with lymphocytes and this result would be used as a basal data of radio-labelling for the cellular trafficking studios in nuclear medicine fields.