• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.164-168
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• 2001

Abel et al. in Germany discovered a new dioxin-responsive gene, which has later been identified as rpt-1 (regulatory protein T-lymphocyte 1). While it is speculated that rpt-1 may play a role in signal transduction and carcinogenesis, its roles and functions remain unknown. The present study attempted to analyze functions of rpt-1 in human epithelial cells following the xenobiotic exposures. While German counterpart analyzed expressionn of rpt-1 in spleen and thymus cells from mouse and rat and characterizes molecular properties of the gene, our work mainly focused on analyzing function of rpt-1 in human skin cells. Expression of rpt-1 in human cells were analyzed by western and northern blot RT-PCR analysis. Expression of rpt-1 as well as Staf-50 in human cells with or without exposure to environmental pollutants were also analyzed by northern blot analysis, since Staf-50 is homologous with rpt-1 and found in human cells. To help study roles of rpt-1 in human cell system, retroviral vector system carrying rpt-1 gene under the CMV promoter were constructed and transfected. Cells overexpressing the gene after the transfection showed an increase of cell density and soft agar colony formations, as compared to the control cells, suggesting that rpt-1 may play a certain role in the transformation processes of human cells. While the expression of rpt-1 in spleen and thymus is known to be strong in the laboratory animals, both the basal and TCDD-induced expression of rpt-1 in the current cellular system remained insignificant. It is speculated that the expression pattern of rpt-1 may be tissue- and species-specific. The present study demonstrated a strong expression of rpt-1 protein in the brain of SD rat model. Since there is no previous report on the expression of rpt-1 in the brain tissue, the result may play a significant role in understanding dioxin-induced neurotoxicities in the future. The present study provides an opportunity to understand a role of rpt-1 in human cell system and suggest a possible lead and basis for the future study of dioxin-induced neurotoxicities.

• Journal of The Korean Association For Science Education
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• v.27 no.3
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• pp.180-189
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• 2007

This study investigated the influences of reciprocal peer tutoring (RPT) strategy on middle school students' science achievement, self-efficacy, perception of instruction by grouping method and science achievement level. Eighth graders from a middle school in Seoul were assigned to comparison, homogeneous RPT, and heterogeneous RPT groups. The students were taught about 'separation of mixtures' for 8 class hours. After the instructions, a science achievement test consisting of three subtests (knowledge, understanding, and application), a self-efficacy test, and a questionnaire about the perception of instruction were administered. The analysis of the results revealed that the scores of heterogeneous RPT group, regardless of the students prior science achievement level, were significantly higher than those of the other groups in the knowledge and understanding subtests, and the self-efficacy test. The scores of homogeneous RPT group were significantly higher than those of the comparison group in the knowledge subtest but not in the understanding subtest and the self-efficacy test. The low-level students in heterogeneous RPT group performed better in the science achievement test and the application subtest than those in the other groups. The high-level students in RPT groups performed better in the science achievement test than those in comparison group. However, there was no significant difference for the application subtest scores of the high-level students of the three groups. Most students in RPT groups perceived positively on the instructions. The students in heterogeneous RPT group and low-level students especially showed more positive perception of the instruction than those in homogeneous RPT group and high-level students.

• Radiation Oncology Journal
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• v.25 no.2
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• pp.109-117
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• 2007

[ $\underline{Purpose}$ ]: To evaluate the incidences and potential predictive factors for symptomatic radiation pneumonitis (SRP) and radiographic pulmonary toxicity (RPT) following adjuvant radiotherapy (RT) for patients with breast cancer. A particular focus was made to correlate RPT with the dose volume histogram (DVH) parameters based on three-dimensional RT planning (3D-RTP) data. $\underline{Materials\;and\;Methods}$: From September 2003 through February 2006, 171 patients with breast cancer were treated with adjuvant RT following breast surgery. A radiation dose of 50.4 Gy was delivered with tangential photon fields on the whole breast or chest wall. A single anterior oblique photon field for supraclavicular (SCL) nodes was added if indicated. Serial follow-up chest radiographs were reviewed by a chest radiologist. Radiation Therapy Oncology Group (RTOG) toxicity criteria were used for grading SRP and a modified World Health Organization (WHO) grading system was used to evaluate RPT. The overall percentage of the ipsilateral lung volume that received ${\geq}15\;Gy\;(V_{15}),\;20\;Gy\;(V_{20})$, and $30\;Gy\;(V_{30})$ and the mean lung dose (MLD) were calculated. We divided the ipsilateral lung into two territories, and defined separate DVH parameters, i.e., $V_{15\;TNGT},\;V_{20\;TNGT},\;V_{30\;TNGT},\;MLD_{TNGT}$, and $V_{15\;SCL},\;V_{20\;SCL},\;V_{30SCL},\;MLD_{SCL}$ to assess the relationship between these parameters and RPT. $\underline{Results}$: Four patients (2.1%) developed SRP (three with grade 3 and one with grade 2, respectively). There was no significant association of SRP with clinical parameters such as, age, pre-existing lung disease, smoking, chemotherapy, hormonal therapy and regional RT. When 137 patients treated with 3D-RTP were evaluated, 13.9% developed RPT in the tangent (TNGT) territory and 49.2% of 59 patients with regional RT developed RPT in the SCL territory. Regional RT (p<0.001) and age (p=0.039) was significantly correlated with RPT. All DVH parameters except for $V_{15\;TNGT}$ showed a significant correlation with RPT (p<0.05). $MLD_{TNGT}$ was a better predictor for RPT for the TNGT territory than $V_{15\;SCL}$ for the SCL territory. $\underline{Conclusion}$: The incidence of SRP was acceptable with the RT technique that was used. Age and regional RT were significant factors to predict RPT. The DVH parameter was good predictor for RPT for the SCL territory while $MLD_{TNGT}$ was a better predictor for RPT for the TNGT territory.

• Journal of The Korean Association For Science Education
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• v.27 no.5
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• pp.394-403
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• 2007

In this study, the effects of reciprocal peer questioning (RPQ) strategy upon students' concept learning were investigated. Ninety-two seventh graders at a co-ed middle school were assigned to control, reciprocal peer tutoring (RPT), and RPQ groups. The students were taught about 'three states of matter' and 'motion of molecules' for 12 class hours. Regardless of students' prior science achievement level, the RPQ group showed the highest scores among the three groups in the test of conceptual understanding, and the RPT group performed better than the control group. For high-level students, the scores of the RPQ group were significantly higher than those of the other groups in the test of the concept application, and those of the RPT group were higher than those of the control group. For low-level students, the scores of the RPT and RPQ groups in the concept application test were significantly higher than those of the control group, while those of the RPT and RPQ groups were not significantly different. These results indicated that verbal interaction by reciprocal tutoring helped students to understand chemical concept learning, and that using self-generated questions was more effective. Therefore, RPQ strategy is suggested to become one of the useful instructional methods to facilitate verbal interaction and concept learning in middle school science instructions.

• Journal of the Korean Chemical Society
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• v.51 no.1
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• pp.82-92
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• 2007

This study investigated the influences of reciprocal peer tutoring strategy and field independencedependence in the instruction enhancing student questions by using weekly reports. Seventh graders (N=152) from a middle school were assigned to WR (weekly reports) and WR-RPT (weekly reports-reciprocal peer tutoring) groups. Students were taught about ‘three states of matter', ‘motion of molecules', and ‘change of states and thermal energy for eighteen class hours and wrote weekly reports six times for the period. The students in the WR-RPT group also conducted reciprocal peer tutoring with the questions of weekly reports which they wrote. The results revealed that the scores of the WR-RPT group were significantly higher than those of the WR group in a conception test regardless of students' field independence-dependence. The field dependent students in the WR-RPT group performed better in an achievement test than those in WR group, while there was no significant difference for the field independent stu dents between the two groups. Additionally, field independent students in each group scored significantly higher than field dependent students in the two tests. Many students, especially having more field independence in the WR-RPT group, perceived WR-RPT positively.

• Tuberculosis and Respiratory Diseases
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• v.59 no.1
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• pp.69-76
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• 2005

Background : Residual pleural thickening (RPT) is the most common complication of tuberculous pleurisy (TP), despite adequate anti-tuberculous chemotherapy. At the conclusion of treatment, 43-50% of patients present RPT, with its incidence varying according to the time of evaluation. To assess the spontaneous resolution of RPT, the RPT at the completion of treatment was compared with that at the final follow-up. The factors related to the development of RPT after the completion of treatment were also studied. Methods : The medical records of sixty four patients, diagnosed with TP between March 2001 and June 2003, were retrospectively. The RPT was measured at the completion of treatment and at the time of the final follow-up and the degree and frequency of RPT compared between the two measurements. Each time, the patients were divided into two groups: those with and without RPT. The clinical characteristics and the radiographic and pleural fluid findings of the two groups were compared. Results : Thirty six (56%) and 27 patients had RPT at the completion of treatment and at the time of the final follow-up, respectively (median follow up period: 8 months). Spontaneous resolution of the RPT was found in 9 patients (24%), and had decrease below 10mm in 15 (42%) during the follow-up period after treatment. The patients were initially divided into two groups: 36 and 27 patients with and without RPT, respectively. There was no predicting factor of RPT, with the exception of the presence of CRP, between the two groups. The patients were also separated into two groups at the time of final visit: 27 and 37 patients with and without RPT, respectively. The patients with RPT were found to have a lower total WBC count in pleural fluid. Conclusion : 57% of patients with RPT were found to have spontaneous resolution of the residual pleural thickening after completion of the chemotherapy. The time of evaluation for RPT and its predicting factors were decided after adequate follow-up, irrespective of the completion of treatment.

• BMB Reports
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• v.54 no.10
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• pp.516-521
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• 2021

Although arginase primarily participates in the last reaction of the urea cycle, we have previously demonstrated that arginase II is an important cytosolic calcium regulator through spermine production in a p32-dependent manner. Here, we demonstrated that rhaponticin (RPT) is a novel medicinal-plant arginase inhibitor and investigated its mechanism of action on Ca²⁺-dependent endothelial nitric oxide synthase (eNOS) activation. RPT was uncompetitively inhibited for both arginases I and II prepared from mouse liver and kidney. It also inhibited arginase activity in both aorta and human umbilical vein endothelial cells (HUVECs). Using both microscope and FACS analyses, RPT treatments induced increases in cytosolic Ca²⁺ levels using Fluo-4 AM as a calcium indicator. Increased cytosolic Ca²⁺ elicited the phosphorylations of both CaMKII and eNOS Ser1177 in a time-dependent manner. RPT incubations also increased intracellular L-arginine (L-Arg) levels and activated the CaMKII/AMPK/Akt/eNOS signaling cascade in HUVECs. Treatment of L-Arg and ABH, arginase inhibitor, increased intracellular Ca²⁺ concentrations and activated CaMKII-dependent eNOS activation in ECs of WT mice, but, the effects were not observed in ECs of inositol triphosphate receptor type 1 knockout (IP3R1^-/-) mice. In the aortic endothelium of WT mice, RPT also augmented nitric oxide (NO) production and attenuated reactive oxygen species (ROS) generation. In a vascular tension assay using RPT-treated aortic tissue, cumulative vasorelaxant responses to acetylcholine (Ach) were enhanced, and phenylephrine (PE)-dependent vasoconstrictive responses were retarded, although sodium nitroprusside and KCl responses were not different. In this study, we present a novel mechanism for RPT, as an arginase inhibitor, to increase cytosolic Ca²⁺ concentration in a L-Arg-dependent manner and enhance endothelial function through eNOS activation.

• Journal of the Korea Concrete Institute
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• v.23 no.4
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• pp.479-486
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• 2011

In this study, we conducted experiment and finite element analysis on the flexural behavior of the round concrete panels according to the evaluation method of biaxial flexural tensile strengths. The Round Panel Test (RPT) and the Biaxial Flexure Test (BFT) were used to determine the biaxial flexural strength of round plain concrete panels. In order to understand the stress distribution on the panels, we measured load-strain relationship at the center of the panels' bottom surface. Test results show that fracture pattern in RPT and BFT panels are similar, and the tensile stress distribution is uniform in all directions at the center of the bottom surface of the panels for both RPT and BFT. The distribution of stresses in two test specimens coincided with the analysis result. The average biaxial flexural strength of RPT is about 29% greater than those of the BFT. The coefficient of variations (COV) of the RPT and BFT for the biaxial flexure strength is 8%, 6%, respectively, which indicates that BFT method is useful and reliable for determining biaxial flexural strengths of the concrete.

• Journal of Life Science
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• v.17 no.2 s.82
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• pp.235-240
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• 2007

AvrRpt2 protein triggers hypersensitive response (HR) and strong disease resistance when it is translocated from a bacterial pathogen Pseudomonas sp. to host plant cells containing a cognate RPS2 resistance protein through Type III Secretion System (TTSS). However, AvrRpt2 protein can function as the effector that suppresses a basal defense and enhances the disease symptom when functional RPS2 resistance protein is absent in the infected plant cells. Using Affymetrix Arabidopsis DNA chip, we found that many genes were specifically regulated by AvrRpt2 protein in the rps2 Arabidopsis mutant. Here, we showed that expression of AtERF11 that is known as a member of B1a subcluster of AP2/ERF transcription factor family was down regulated specifically by AvrRpt2. To determine its function in plant resistance, we also generated the Arabidopsis thaliana transgenic plants constitutively overexpressing AtERF11 under CaMV 355 promoter, which conferred an enhanced resistance against a bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. Thus, these results collectively suggest that AtERF11 plays a role as a positive regulator for disease resistance against biotrophic bacterial pathogen in plant.

• Convergence Security Journal
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• v.2 no.2
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• pp.1-8
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• 2002

Real-Time Protocol (RTP) is used for multimedia information transmission and RTP payload must be encrypted for providing multimedia information security. Encryption/decryption delay is minimized, because there are constraints in transporting a multimedia data through the Internet. Therefore, encryption algorithm is changed with considering network traffic and load. Doting many users participate in the same multimedia service, an user who already left the service can receive and decrypt the RTP payload because of knowing the encryption key. In this paper, Security Control Protocol for RTP is designed and implemented for changing the encryption algorithm and the key.