• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.10 no.5
• /
• pp.240-249
• /
• 1985

This paper proposes the requirements of protocol testing, the protocol test methods and the architecture of PTF. Also this paper includes the test sequences and the test results for X.25 DTE packet level protocol.

• Phonetics and Speech Sciences
• /
• v.2 no.3
• /
• pp.157-164
• /
• 2010

This study investigated the characteristics of two aerodynamic indices, PTP (Phonation threshold pressure) and PTF (Phonation threshold flow) in patients with ADSD (adductor spasmodic dysphonia) and to see if two new aerodynamic indices can differentiate between normal and ADSD group. Additionally, PTP and PTF values were compared in terms of overall severity of ADSD in the patient group. The severity of ADSD was rated on a 7-point rating scale by two experienced speech language pathologists. The Kay Elemetrics Phonatory Aerodynamic System (PAS) (Kay Elemetrics Corp., Lincoln Park, NJ) was used to collect PTP and PTF measurements from 16 female normal subjects, 31 female patients with ADSD. Significantly lower PTF values (P< 0.05) were observed in ADSD when compared to those of normal control. Also, significantly lower PTF values in severe ADSD patients (P<.001). However, PTP could not distinguish patients with ADSD from control groups (P=0.119) and among the ADSD groups according to the severity (P=0.177). Consequently, PTF was more sensitive than PTP which might differentiate between normal speakers and ADSD and among different levels of severity within ADSD, suggesting that PTF could be a useful diagnostic parameter to measure the aerodynamic function of ADSD and provide the neurolaryngeal dysfunction in patients with ADSD.

• Microbiology and Biotechnology Letters
• /
• v.50 no.2
• /
• pp.310-318
• /
• 2022

The fruits of Paulownia tomentosa (Thunb.) (PT) Steud. have been reported to exert a variety of biological activities. A previous study confirmed that compounds isolated from PT fruits (PTF) exerted anti-inflammatory effects on TNF-α-stimulated airway epithelial cells. However, there is no report on the protective effects of PTF on acute lung injury (ALI). Here, we examined the ameliorative effects of PTF in an experimental animal model of lipopolysaccharide (LPS)-induced ALI. In ALI mice, increased levels of inflammatory cell influx were confirmed in the lungs of mice, and an increase of microphage numbers, TNF-α, IL-6 and MCP-1 production and protein content were detected in mouse bronchoalveolar lavage fluid. However, these increases were significantly reversed with PTF pretreatment. In addition, PTF inhibited the increased expression of iNOS and COX-2 in the lungs of ALI mice. Furthermore, the upregulation of MAPK and NF-κB activation was decreased in the lungs of ALI mice by PTF. In the in vitro experiment, PTF pretreatment exerted an anti-inflammatory effect by inhibiting the secretion of nitric oxide, TNF-α and IL-6 in LPS-stimulated RAW264.7 macrophages. Collectively, these results indicated that PTF has ameliorative effects on airway inflammation in an experimental animal model of ALI.

• Biomolecules & Therapeutics
• /
• v.20 no.1
• /
• pp.89-95
• /
• 2012

Poncirus trifoliata fruit (PTF) affects the digestive and cardiovascular systems, and kidney function. The authors studied the effects of ethyl acetate (EtOAc) extract of PTF on the activities of osteoblasts and in an animal model. The main compounds of the EtOAc extract, naringin and poncirin have been confirmed by HPLC and NMR analysis. Effects of osteoblastic differentiation were measured by alkaline phosphatase (ALP) activity, osteopontin (OPN) protein expression and osteoprotegerin (OPG) mRNA expression in MC3T3-E1 cells. Also, osteoclast differentiation was measured by multinucleated cells (MNCs) formation through tartrate resistance acid phosphatase (TRAP)-positive staining. Bone mineral density (BMD) was measured before and after treatment with EtOAc extract of PTF in prednisolone-induced osteoporotic mice. Dexamethasone (DEX) decreased OPN and OPG expression level in MC3T3-E1 cells and ALP activity was decreased by DEX dose-dependently. EtOAc extract of PTF recovered the levels of ALP activity, and the expression of OPN and OPG in MC3T3-E1 cells treated with DEX. In osteoclast differentiation, multinucleated TRAP-positive cell formation was significantly suppressed by the EtOAc extract of PTF. Total body BMD was restored by EtOAc extract of PTF in prednisolone-induced osteoporotic mice. In conclusion, EtOAc extract of PTF recovered DEX-mediated deteriorations in osteoblastic and osteoclastic functions, and increased BMD in glucocorticoid-induced osteoporosis.

• Journal of Chest Surgery
• /
• v.25 no.8
• /
• pp.863-870
• /
• 1992

The low profile Ionescu-Shiley pericardial xenograft valve had been initially introduced to have improved hemodynamic performance and expected superior durability, However, subsequent clinical reports and laboratory studies have repeatedly indicated early failure of the valve from mechanical reasons in valve design, A total and consecutive 169 patients underwent isolated MVR with the low profile Ionescu-Shiley valve at Seoul National University Hospital from November 1984 to October 1989 [Group ISLM]. Five patients [3.0%] died within 30 days of surgery, and early survivors were followed up for 734.9 patient-years [Mean$\pm$SD, 4.9$\pm$2.0 years], Late mortality rate was 0.136% /patient-year [pt-yr], Linearized incidences of major complications were: 0.953% embolism /pt-yr; 0.680% bleeding /pt-yr; 0.272% endocarditis /pt-yr; and 0, 408% primary tissue failure [PTF] /pt-yr, The actuarial survival was 99.4$\pm$0.6%, and probabilities of from thromboembolism and from PTF were 90.7$\pm$4.6% and 95.9$\pm$2.6% at 8 years, respectively These results were compared with the clinical data from the 291 patients of isolated MVR with the standard Ionescu-Shiley valve at the same hospital during the period between October 1978 and June 1983 [Group ISUM], Group ISUM included 11% of patients younger than 15 years of age, whereas Group ISLM did no patient of this age. The mean age at the time of surgery was significantly younger in Group ISUM than one in Group ISLM [P<0.001]. Differences were not statistically significant in operative mortality, mean follow-up period and linearized incidences of thromboembolism, bleeding and endocarditis, between two groups, However, the linearized rate of PTF was lower [P<0.001] and probabilities of freedom fro PTF higher [P<0.001] in Group ISLM at least up to postoperative 8 years. While the features of PTF of the standard valve was predominantly degeneration with calcification and stenosis, the ones of the low profile valve was cusp tear and incompetence. It remains, however, to be seen whether the low profile valve fails mostly from mechanical reason, and further follow-up will still be necessary to determine the differences in mode of PTF of two valves.

• Journal of Chest Surgery
• /
• v.22 no.6
• /
• pp.980-989
• /
• 1989

The Hancock porcine xenograft valves had been used in Seoul National University Hospital, mainly because of their antithrombogenicity despite of the predicted failure, from March 1976 to April 1984, and a total and consecutive 163 patients were retrospectively studied for late results with the special stress on the structural failure. The hospital mortality rate [within 30 days] was 6.1 %, and the 153 early survivors were followed up for a total of 822.9 patient-years [p-y][Mean * SD 5.38 * 3.02 years]. The linealized late mortality was 1.823%/p-y. Four major complications related to the Hancock valve were: 1.822% thromboembolism/p-y; 0.729 % bleeding/p-y; 0.972% endocarditis/p-y; 3.646% overall valve failure/p-y and 2.187 % primary tissue failure [PTF]/p-y. The actuarial survival rates at 5 and 10 years were 94.90 * 1.89% and 80.58 * 5.21 %; and the probabilities of freedom from thromboembolism at 5 and 10 years were 90.93 * 2.63% and 83.35 * 7.64 9o respectively. The probabilities from PTF at 5, 10 and 12 years were 98.02 * 1.39%, 60.62 * 8.89% and 49.60 * 12.34 %. One hundred-eighteen patients [72.4%] had single MVR [age, 34.0 * 10.9 years] with the operative mortality rate of 4.2%; and 113 early survivors were followed up for a total 616.4 patient-years[5.46 * 2.96 years]. The late mortality rate was 1.460 %/p-y. The major complications were: 1.622 % thromboembolism /p-y; 0.487% bleeding/p-y; 0.649 % endocarditis/p-y; 2.920% primary valve failure/p y and 1.785% PTF/p-y. The actuarial survival rates were 97.08 * 1.67%[at 5 years] and 81.27 * 6.64%[at 10 years], and the probabilities of freedom from thromboembolism 92.44 * 2.76 %[at 5 years] and 80.89 * 11.08%[at 10 years]. The probabilities of freedom from PTF at 5 and 10 years were 98 70 * 1.29% and 65.59 * 9.78% respectively. The mean age of 11 patients of PTF was 25.7 * 8.8 years and the valve extraction period 7.16 * 1.45 years. Failure of bioprosthetic xenograft valves are reportedly known to occur earlier in young patients in an accelerated fashion. The study with two groups divided into the cumulative younger and the cumulative older patients according to the age limits of 5-year interval strongly suggested these tendency. Although PTF began to occur past postoperative 5 years and the probabilities of freedom from PTF increased as the age limits raised and the number of patients increased in the cumulative younger patients while they decreased as the age limits lowered and the number of patients increased in the cumulative older patients, the definite age limits from which the Hancock valve can be safely recommended could not be obtained. From the results, the Hancock valves are contraindicated in patients younger than 20 to 25 years and may be safely recommended in patients older than 45 years as a tentative conclusion. Further longitudinal study may define these age factors.

• Journal of Ginseng Research
• /
• v.47 no.5
• /
• pp.638-644
• /
• 2023

Background: The anti-platelet activity of the saponin fraction of Korean Red Ginseng has been widely studied. The saponin fraction consists of the panaxadiol fraction (PDF) and panaxatriol fraction (PTF); however, their anti-platelet activity is yet to be compared. Our study aimed to investigate the potency of anti-platelet activity of PDF and PTF and to elucidate how well they retain their anti-platelet activity via different administration routes. Methods: For ex vivo studies, Sprague-Dawley rats were orally administered 250 mg/kg PDF and PTF for 7 consecutive days before blood collection via cardiac puncture. Platelet aggregation was conducted after isolation of the washed platelets. For in vitro studies, washed platelets were obtained from Sprague-Dawley rats. Collagen and adenosine diphosphate (ADP) were used to induce platelet aggregation. Collagen was used as an agonist for assaying adenosine triphosphate release, thromboxane B2, serotonin, cyclic adenosine monophosphate, and cyclic guanosine monophosphate (cGMP) release. Results: When treated ex vivo, PDF not only inhibited ADP and collagen-induced platelet aggregation, but also upregulated cGMP levels and reduced platelet adhesion to fibronectin. Furthermore, it also inhibited Akt phosphorylation induced by collagen treatment. Panaxadiol fraction did not exert any antiplatelet activity in vitro, whereas PTF exhibited potent anti-platelet activity, inhibiting ADP, collagen, and thrombin-induced platelet aggregation, but significantly elevated levels of cGMP. Conclusion: Our study showed that in vitro and ex vivo PDF and PTF treatments exhibited different potency levels, indicating possible metabolic conversions of ginsenosides, which altered the content of ginsenosides capable of preventing platelet aggregation.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• v.y2005m4
• /
• pp.168-175
• /
• 2005

The pressurization system in a liquid rocket propulsion system provides a controlled gas pressure in the ullage space of the vehicle propellant tanks. It is advantage to employ a hot gas heat exchanger in the pressurization system to increase the specific volume of the pressurant and thereby reduce over-all system weight. A significant improvement in pressurization-system performance can be achieved, particularly in a cryogenic system, where the gas supply is stored inside the cryogenic propellant tank. The temperature characteristic of cryogenic pressurant is very important to develop some components in pressurization system. Numerical modeling and Test data were studied using SINDA/FLUINT Program and PTF(Propellant-feeding Test Facility).

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.19 no.4
• /
• pp.679-684
• /
• 1994

Progressive transmission using optimum bit-ordering of discrete cosine transform(DCT) coded image is proposed to reconstruct a better image in a few bits among all the coded bits at the receiver. It is to transmit the bit gradually to reduce the distrotion of the reconstructed image most by transmitting one more bit. To do this, the power transfer factor(PTF) which is the squared value of difference between the reconstruction level of embedded quantizer and another reconstruction level made by transmitting one more bit is defined. And then, the transmission order of bits is obtained by sorting the PTFs of the coded bits. As a results, the proposed method can reconstruct image having less distortion and better quality at the same bit rate than the conventional zig-zag scan.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.9 no.3
• /
• pp.66-73
• /
• 2005

The pressurization system in a liquid rocket propulsion system provides a controlled gas pressure in the ullage space of the vehicle propellant tanks. It is advantage to employ a hot gas heat exchanger in the pressurization system to increase the specific volume of the pressurant and thereby reduce over-all system weight. A significant improvement in pressurization-system performance can be achieved, particularly in a cryogenic system, where the gas supply is stored inside the cryogenic propellant tank. In this study liquid nitrogen was used instead of liquid oxygen as a simulant. The temperature characteristic of cryogenic pressurant is very important to develop some components in pressurization system. Numerical modeling and test data were studied using SINDA/FLUINT Program and PTF(Propellant-feeding Test facility).