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1.
Micromachines (Basel) ; 15(7)2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39064428

ABSTRACT

Piezoelectric composites, which consist of piezoelectric materials and polymers, are widely employed in various applications such as underwater sonar transducers and medical diagnostic ultrasonic transducers. Acoustic transducers based on piezoelectric composites can have high sensitivity with broad bandwidth. In recent studies, it is demonstrated that 2-2 composites based on single crystals provide further increased sensitivity and wide bandwidth. In order to utilize a 2-2 composite in acoustic sensors, it is required to demonstrate the full material coefficients of the 2-2 composite. In this study, we investigated an analytic solution for determining equivalent material coefficients of a 2-2 composite. Impedance spectrums of the single-phase resonators with equivalent material coefficients and 2-2 composite resonators were compared by the finite element method in order to verify the analytic solutions. Furthermore, the equivalent material coefficients derived from the analytic solution were also verified by comparing the measured and the simulated impedance spectrums. The difference in resonance and anti-resonance frequencies between the measured and simulated impedance spectrums was around 0.5% and 1.2%. By utilizing the analytic solutions in this study, it is possible to accurately derive full equivalent material coefficients of a 2-2 composite, which are essential for the development of acoustic sensors.

2.
JSES Int ; 7(3): 439-444, 2023 May.
Article in English | MEDLINE | ID: mdl-37266175

ABSTRACT

Background: Rotator cuff posterior delamination and subscapularis tear are commonly observed in rotator cuff injuries. However, there are very few studies on the relationship between posterior delamination and subscapularis tendon tear. This study aimed to investigate the relationship between posterior delamination and subscapularis tendon tear. Methods: The study was conducted from March 2018 to June 2021 with 553 patients who underwent rotator cuff repairs at two institutions. The age and gender, size of rotator cuff tear, duration of symptoms, range of motion of shoulder joint, visual analog scale score, Korean Shoulder Scale score, gap and width of rotator cuff tear, and fatty degeneration of the supraspinatus and infraspinatus muscles were compared to confirm the differences between a delaminated and nondelaminated rotator cuff tear. Moreover, the proportions of the subscapular tendon rupture and subscapularis tendon rupture according to the size of the rotator cuff tear were analyzed in both the delaminated and nondelaminated rotator cuff tear groups. Results: Compared to the nondelaminated rotator cuff tear group, the age of the delaminated rotator cuff tear group was significantly higher, and as the size of the rotator cuff tear increased, the proportion of delaminated tear increased (P < .001). Furthermore, the duration of symptoms was longer, visual analog scale score was higher, Korean Shoulder Scale score was lower, gap and width of rotator cuff as well as fatty degeneration of the supraspinatus and infraspinatus were more severe in the group with posterior delamination than that without. In the nondelaminated rotator cuff tear group, 212 subjects (84.46%) had no subscapularis tear, and 39 subjects (15.54%) had subscapularis tear. In the delaminated rotator cuff tear group, 103 subjects (34.11%) had no subscapular tendon tear while 199 subjects (65.89%) had a subscapular tendon tear (P < .001). Furthermore, as the size of the rotator cuff tear increased, the rate of subscapular tendon tear increased in both the delaminated and nondelaminated rotator cuff tear groups. Conclusions: The results suggest that there is a high probability of concomitant rupture of the subscapularis tendon in the patient group with posterior delamination tear. Therefore, it should be noted that if a posterior delamination is confirmed during surgery, it is necessary to carefully check for rupture of the scapular tendon.

3.
Sensors (Basel) ; 23(7)2023 Mar 24.
Article in English | MEDLINE | ID: mdl-37050505

ABSTRACT

Piezoelectric composites, which consist of a piezoelectric material and a polymer, have been extensively studied for the applications of underwater sonar sensors and medical diagnostic ultrasonic transducers. Acoustic sensors utilizing piezoelectric composites can have a high sensitivity and wide bandwidth because of their high piezoelectric coefficient and low acoustic impedance compared to single-phase piezoelectric materials. In this study, a thickness-mode driving hydrophone utilizing a 2-2 piezoelectric single crystal composite was examined. From the theoretical and numerical analysis, material properties that determine the bandwidth and sensitivity of the thickness-mode piezoelectric plate were derived, and the voltage sensitivity of piezoelectric plates with various configurations was compared. It was shown that the 2-2 composite with [011] poled single crystals and epoxy polymers can provide high sensitivity and wide bandwidth when used for hydrophones with a thickness resonance mode. The hydrophone element was designed and fabricated to have a thickness mode at a frequency around 220 kHz by attaching a composite plate of quarter-wavelength thickness to a hard baffle. The fabricated hydrophone demonstrated an open circuit voltage sensitivity of more than -180 dB re 1 V/µPa at the resonance frequency and a -3 dB bandwidth of more than 55 kHz. The theoretical and experimental studies show that the 2-2 single crystal composite can have a high sensitivity and wide bandwidth compared to other configurations of piezoelectric elements when they are used for thickness-mode hydrophones.

4.
Sensors (Basel) ; 23(2)2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36679608

ABSTRACT

In this study, two thin rectangular PVDFs were installed in the form of a cantilever on a FTEH (funnel-type energy harvester), and a CTEH (cymbal-type energy harvester) was fabricated in a form coupled to the upper part of the support. As a result of measuring the energy harvesting sensitivity according to the installation direction of the CTEH, a high voltage was measured in the structure installed on top of the support across all flow velocity conditions. A composite structure PVDF energy harvester combining CTEH and FTEH was fabricated and the amount of power generated was measured. As a result of measuring the open-circuit voltage of the PVDF energy harvester device with a composite structure to which the optimum resistance of CTEH of 241 kΩ and the optimum resistance of FTEH of 1474 kΩ were applied at a flow rate of 0.25 m/s, the output voltage compared to the RMS average value was 7 to 8.5 times higher for FTEH than for CTEH. When the flow rate was 0.5 m/s, the electrical energy charged for 500 s was measured as 2.0 µWs to 2.5 µWs, and when the flow speed was 0.75 m/s, it reached 2.5 µWs when charged for 300 s, generating the same amount when the flow rate increased by 50%. The time to do it was reduced by 66.7%.


Subject(s)
Electricity , Physical Phenomena
5.
Micromachines (Basel) ; 13(4)2022 Apr 07.
Article in English | MEDLINE | ID: mdl-35457886

ABSTRACT

For the purpose of stably supplying electric power to the underwater wireless sensor, the energy harvesting technology in which a voltage is obtained by generating displacement in a piezoelectric material using flow-induced vibration is one of the most attractive research fields. The funnel type energy harvester (FTEH) with PVDF proposed in this study is an energy harvester in which the inlet has a larger cross-sectional area than the outlet and a spiral structure is inserted to generate a vortex flow at the inlet. Based on numerical analysis, when PVDF with L = 100 mm and t = 1 mm was used, the electric power of 39 µW was generated at flow velocity of 0.25 m/s. In experiment the average RMS voltage of FTEH increased by 0.0209 V when the flow velocity increased by 1 m/s. When measured at 0.25 m/s flow velocity for 25 s, it was shown that voltage doubler rectifier (VDR) generated a voltage of 133.4 mV, 2.25 times larger than that of full bridge rectifier (FBR), and the energy charged in the capacitor was 44.3 nJ, 14% higher in VDR than that of the FBR. In addition, the VDR can deliver power of 17.75 µW for 1 kΩ load. It is shown that if the voltage generated by the FTEH using the flow velocity is stored using the VDR electric circuit, it will greatly contribute to the stable power supply of the underwater wireless sensor.

6.
Sensors (Basel) ; 23(1)2022 Dec 23.
Article in English | MEDLINE | ID: mdl-36616739

ABSTRACT

Polyvinylidene fluoride (PVDF) is an emerging method for energy harvesting by fluid motion with superior flexibility. However, the PVDF energy harvester, which has a high internal impedance and generates a low voltage, has a large power transmission loss. To overcome this problem, we propose an impedance-coupled voltage-boosting circuit (IC-VBC) that reduces the impedance of the PVDF energy harvester and boosts the voltage. SPICE simulation results show that IC-VBC reduces the impedance of the PVDF energy harvester from 4.3 MΩ to 320 kΩ and increases the output voltage by 2.52 times. We successfully charged lithium-ion batteries using the PVDF energy harvester and IC-VBC with low-speed wind power generation.

7.
Cancer Chemother Pharmacol ; 81(2): 393-398, 2018 02.
Article in English | MEDLINE | ID: mdl-29294168

ABSTRACT

Induction of complete remission (CR) is imperative for long-term survival in adult acute lymphoblastic leukemia (ALL) patients regardless of transplantation eligibility. Hyper-CVAD chemotherapy is a widely-used frontline remission induction regimen for these patients. We conducted a pilot trial of frontline remission induction using daunorubicin-augmented hyper-CVAD regimen (hyper-CVDD) in adult ALL patients (n = 15). The CR rate after this modified regimen was 100% (n = 15). Twelve patients were able to proceed to allogeneic hematopoietic cell transplantation, two patients died before transplantation due to infection, and the remaining one who was ineligible for transplant due to her age received an additional five courses of consolidation chemotherapy. Overall survival (OS) and event-free survival (EFS) of the study patients was 61.0 and 47.5% at 3 years. OS and relapse-free survival of transplanted patients was 66.8 and 55.0% at 3 years. This pilot trial demonstrates the favorable efficacy of the hyper-CVDD chemotherapy as a frontline remission induction regimen. Further clinical trials using this regimen are warranted.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Induction Chemotherapy/methods , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Adolescent , Adult , Aged , Antibiotics, Antineoplastic/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Blood Cell Count , Cyclophosphamide/administration & dosage , Daunorubicin/administration & dosage , Dexamethasone/administration & dosage , Doxorubicin/administration & dosage , Female , Hematopoietic Stem Cell Transplantation/methods , Humans , Male , Middle Aged , Pilot Projects , Recurrence , Remission Induction , Survival Analysis , Treatment Outcome , Vincristine/administration & dosage , Young Adult
8.
Arch Orthop Trauma Surg ; 137(3): 357-365, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28132087

ABSTRACT

INTRODUCTION: This study was performed to compare ACL graft maturation and morphologies using MRI between trans-tibial (TT) and retrograde outside-in (OI) techniques, and to compare clinical outcomes between the two groups. MATERIALS AND METHODS: Patients underwent single-tunnel ACL reconstruction using quadrupled hamstring autografts, with the TT technique used on 42 patients (TT group) and the retrograde OI technique used on 39 patients (OI group). All patients were examined with 3 T MRI at 6 months (between 5 and 7 months) after surgery. The signal intensity of the reconstructed graft was analyzed and compared between the two groups, using the signal/noise quotient (SNQ), the orientation of the ACL graft and the tibial tunnel location of the graft. The SNQ value is indicative of graft maturation, and the orientation of the graft and the tibial tunnel location of the graft represent graft morphology. Clinical evaluation was performed before the surgery and 2 years or more after the surgery. RESULTS: The mean SNQ value of the TT group was significantly (P = 0.030) lower than that of the OI group. The mean sagittal ACL angle (P < 0.001) and the mean coronal ACL angle (P < 0.001) were more vertical in the TT group. The tibial tunnel aperture was located at a significantly (P < 0.001) more posterior position in the TT group. There was no statistically significant difference in the clinical results between the two groups. CONCLUSIONS: The OI technique showed a more anteriorly positioned tibial tunnel and a more oblique graft orientation in both sagittal and coronal planes. However, in comparison with the TT group, a significantly higher SNQ value was noticed in the follow-up MRI of the OI group at 6 months, although clinical results of the two groups were not significantly different during at least the 2-year follow-up.


Subject(s)
Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction/methods , Anterior Cruciate Ligament/diagnostic imaging , Autografts/diagnostic imaging , Hamstring Tendons/transplantation , Magnetic Resonance Imaging , Adult , Anterior Cruciate Ligament/surgery , Case-Control Studies , Female , Femur/surgery , Humans , Knee Joint/surgery , Male , Retrospective Studies , Tibia/surgery , Transplantation, Autologous , Young Adult
9.
Cancer Res Treat ; 49(1): 255-262, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27188198

ABSTRACT

PURPOSE: A meta-analysis was conducted to examine the question of whether combination regimens are more effective than monotherapy as a second-line chemotherapy in advanced gastric cancer. MATERIALS AND METHODS: The MEDLINE and the EMBASE databases and the Cochrane Central Register for Controlled Trials were searched using appropriate keywords. Only randomized controlled trials were eligible. RESULTS: Taxane-based study is rare; thus, four irinotecan-based studies were finally included in the meta-analysis. Out of 661 patients, 331 patients were assigned to combination therapy and 330 to monotherapy. Cisplatin or fluoropyrimidine (S-1 or 5-fluorouracil) was used as a combination partner to irinotecan. The pooled hazard ratio (HR) for overall survival (OS) and for progression-free survival (PFS) was 0.938 (95% confidence interval [CI], 0.796 to 1.104; p=0.442) and 0.815 (95% CI, 0.693 to 0.958; p=0.013). In subgroup analysis according to previous exposure to a partner agent, the PFS benefit of combination was observed only in the partially exposed group (HR, 0.784; 95% CI, 0.628 to 0.980; p=0.032). CONCLUSION: Second-line irinotecan-based combination was not associated with increased OS, but with PFS benefit, which seemed particularly significant for patients receiving combination with a new agent.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Camptothecin/analogs & derivatives , Stomach Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Camptothecin/administration & dosage , Camptothecin/adverse effects , Camptothecin/therapeutic use , Humans , Irinotecan , Neoplasm Staging , Proportional Hazards Models , Publication Bias , Retreatment , Stomach Neoplasms/diagnosis , Stomach Neoplasms/mortality , Survival Analysis , Treatment Outcome
10.
Hip Pelvis ; 28(3): 157-163, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27777918

ABSTRACT

PURPOSE: The purpose of this study was to analyze the questions in the hip and pelvis section of the Korean Orthopaedic In-Training Examination (KOITE). MATERIALS AND METHODS: We analyzed all KOITE questions pertaining to hip and pelvis surgery between 2010 and 2014. A thorough analysis of the contents was performed after categorizing as tested topics, imaging modalities used, taxonomic classification, and recommended references. We also analyzed the scores of the hip and pelvis section of the KOITE. RESULTS: Seventy-five of five-hundred questions (weight, 15.0%) were related to the hip and pelvis. Trauma including fracture and dislocation (26/75, 34.7%) was asked more commonly than disease and basics. The description-only questions (65/75, 86.7%) were the most frequently asked. According to taxonomic classification, taxonomy 3 (decision; 39/75, 52.0%) was most frequently asked. Campbell's Operative Orthopedics (52/75, 69.3%) was the reference that covered most of the questions. CONCLUSION: This analysis of the hip and pelvis section of KOITE could be used for resident training programs in teaching hospitals.

11.
J Eval Clin Pract ; 22(6): 887-891, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27151774

ABSTRACT

RATIONALE, AIMS AND OBJECTIVES: The purpose of this study was to verify the effect of pop-up messages (regarding a history of dual-energy X-ray absorptiometry [DXA]) on the identification and management of osteoporosis after osteoporotic hip or spine fractures. We hypothesized that these pop-up messages would increase the awareness and management of osteoporosis among clinicians and patients. METHODS: We introduced pop-up messages regarding a history of DXA in our Order Communication System (March 2012) and evaluated the records of 404 patients who were treated between January 2011 and December 2012. The patients were categorized as being treated without the pop-up messages (Group I, before March 2012) or with the pop-up messages (Group II, after March 2012). We compared their rates of DXA prescription, osteoporosis medication, exercise, mortality and subsequent refractures during a 2-year follow-up. RESULTS: After introducing the pop-up messages, the DXA prescription rate increased from 35.1 to 57.1% (P < 0.001), the osteoporosis medication rate increased from 21.1 to 25.2% (P = 0.05) and the exercise rate increased from 35.6 to 40.5% (P = 0.018). During the 2-year follow-up, the mortality rates were 4.64% in Group I and 6.67% in Group II (P = 0.4). Subsequent refractures were found in 12.9% of Group I patients and 9.52% of Group II patients (P = 0.87). CONCLUSION: The pop-up messages positively affected the behaviours of orthopaedic surgeons and were associated with increased rates of prescription of DXA, osteoporosis medication, and might affect the behaviour of patient, increased exercise rate. Therefore, we recommend using this simple and effective method to improve physicians' awareness of osteoporosis.


Subject(s)
Awareness , Communication , Osteoporosis , Absorptiometry, Photon , Aged , Ambulatory Care Facilities , Electronic Health Records , Female , Humans , Male , Osteoporosis/drug therapy , Osteoporotic Fractures/prevention & control , Republic of Korea , Retrospective Studies , Software , Spinal Fractures/prevention & control
12.
Ann Hematol ; 95(3): 483-91, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26658911

ABSTRACT

Methotrexate (MTX) toxicity can hamper the administration of all planned doses in acute graft-versus-host disease (GVHD) prophylaxis following allogeneic hematopoietic stem cell transplantation. Reduction or omission of MTX doses results in an increased risk of acute GVHD. In this prospective observational study, we compared the incidence of GVHD and the transplant outcomes between patients who received the full treatment course of MTX (group 1), patients in whom MTX doses were omitted if MTX toxicity developed (group 2), and patients receiving corticosteroid instead of MTX if MTX toxicity developed (group 3). The cumulative incidence of grades II-IV acute GVHD at 100 days post-transplantation was 22.2 % in group 1, 43.6 % in group 2, and 25.0 % in group 3 (P = 0.132). The risk of grades II-IV acute GVHD in group 2 was higher than that in group 1 (hazard ratio (HR) 3.262, P = 0.016), but the risk in group 3 was similar to that in group 1 (HR 0.960, P = 0.890). Group 3 also showed a trend towards a lower risk of chronic GVHD compared to the other groups. The cumulative risk of chronic GVHD at 2 years was 73.9, 71.6, and 33.3 % in groups 1, 2, and 3, respectively (P = 0.084). However, a likely higher relapse incidence and infection-related mortality in group 3 produced a trend towards the lowest relapse-free survival (2-year RFS, 46.3, 49.3, and 25.0 % in groups 1, 2, and 3, respectively; P = 0.329) and overall survival (2-year OS, 45, 52.3, and 25 %, respectively; P = 0.322) in group 3. Although the substitution of MTX with corticosteroid ameliorates the increased risk of GVHD in patients in which it is imperative to omit its dose, its negative impact on relapse and infection risk does not result in favorable transplant outcomes.


Subject(s)
Adrenal Cortex Hormones/administration & dosage , Drug Substitution , Graft vs Host Disease/prevention & control , Methotrexate/administration & dosage , Methotrexate/adverse effects , Adolescent , Adult , Aged , Cohort Studies , Drug Substitution/methods , Female , Graft vs Host Disease/diagnosis , Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cell Transplantation/methods , Humans , Male , Middle Aged , Prospective Studies , Transplantation Conditioning/adverse effects , Transplantation Conditioning/methods , Young Adult
13.
Oncologist ; 20(12): 1440-7, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26512046

ABSTRACT

BACKGROUND: A combination of serotonin receptor (5-hydroxytryptamine receptor type 3) antagonists, NK-1 receptor antagonist, and steroid improves the complete response (CR) of chemotherapy-induced nausea and vomiting (CINV) in cancer patients. Ramosetron's efficacy in this triple combination regimen has not been investigated. This prospective, multicenter, single-blind, randomized, phase III study compares a combination of ramosetron, aprepitant, and dexamethasone (RAD) with a combination of ondansetron, aprepitant, and dexamethasone (OAD) to prove the noninferiority of RAD in controlling highly emetogenic CINV. METHODS: Aprepitant and dexamethasone were orally administered for both arms. Ramosetron and ondansetron were intravenously given to the RAD and OAD groups. The primary endpoint was no vomiting and retching and no need for rescue medication during the acute period (day 1); the noninferiority margin was -15%. RESULTS: A total of 299 modified intention-to-treat cancer patients who received RAD (144 patients) and OAD (155 patients) were eligible for the efficacy analysis. The CR rates of RAD versus OAD were 97.2% versus 93.6% during the acute period, 77.8% versus 73.6% during the delayed period (day 2-5), and 77.1% versus 71.6% during the overall period. Furthermore, RAD was noninferior to OAD in subgroups stratified by age, cancer type, chemotherapeutic agents, and schedule. Repeated measures analysis showed that in male patients, RAD was superior to OAD. Profiles of adverse events were similar in both groups. CONCLUSION: RAD is as effective and tolerable as OAD for CINV prevention in patients receiving highly emetogenic chemotherapy. Ramosetron could be considered one of the best partners for aprepitant.


Subject(s)
Antiemetics/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Nausea/drug therapy , Neoplasms/drug therapy , Vomiting/drug therapy , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Aprepitant , Benzimidazoles/therapeutic use , Dexamethasone/therapeutic use , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Morpholines/therapeutic use , Nausea/chemically induced , Ondansetron/therapeutic use , Prospective Studies , Single-Blind Method , Treatment Outcome , Vomiting/chemically induced
15.
Korean J Radiol ; 12(1): 107-12, 2011.
Article in English | MEDLINE | ID: mdl-21228946

ABSTRACT

OBJECTIVE: We wanted to evaluate the efficacy of stent placement using the coaxial technique with a stiff, long introducer sheath in patients with technical failure using an angiographic catheter for the obstructions proximal to the descending colon. MATERIALS AND METHODS: Self-expandable metallic stent placement was attempted under fluoroscopy-guidance in 77 consecutive patients who had malignant colorectal obstruction. Stent placement was performed using an angiographic catheter and a guide wire. If the angiographic catheter could not be advanced over the guide wire into the obstructive lesions proximal to the descending colon, then a 6-Fr introducer sheath was used. The technical success rate, the clinical success rate and the complications were analyzed. RESULTS: Successful stent placement was achieved in 75 of 77 patients (97%). The angiographic catheter failed to advance into the obstructive lesions of 11 patients (M:F = 7:4; mean age, 65.5 years) whose lesions were at the level of the splenic flexure or transverse colon. Therefore, the coaxial technique was implemented in all these 11 patients using a 6-Fr stiff introducer sheath and then the stent placement was successful. There were no complications related to the use of a stiff introducer sheath. Clinical success, which was defined as relief of clinical obstructive bowel symptoms, was obtained within 24 hours in all of patients. CONCLUSION: The coaxial technique using a stiff introducer sheath can increase the technical success of fluoroscopy-guided, self-expandable metallic stent placement in patients with colonic obstruction proximal to the descending colon.


Subject(s)
Catheters , Colon, Descending , Colonic Diseases/therapy , Fluoroscopy , Intestinal Obstruction/therapy , Radiography, Interventional , Stents , Adult , Aged , Aged, 80 and over , Colonic Diseases/etiology , Colonic Neoplasms/complications , Female , Humans , Intestinal Obstruction/etiology , Male , Middle Aged
16.
J Gen Psychol ; 137(4): 343-61, 2010.
Article in English | MEDLINE | ID: mdl-21086857

ABSTRACT

Previous studies have reported that our interpersonal knowledge shows an asymmetry; that is, we tend to believe that we know and understand other people's thoughts and feelings better than other people know and understand our own thoughts and feelings. In the present study, the authors compared American (114 men, 192 women) and Korean (99 men and 98 women) students to examine whether the asymmetry is greater in collectivistic than in individualistic culture in two types of relationships: horizontal (with best friends) and vertical (with parents). On all three items--Know, Understand, and Visibility--asymmetry was found for both horizontal and vertical relationships. Further, the Understand and Visibility items showed greater asymmetry for the Korean group than for the American group. It was concluded that asymmetry is greater in collectivistic than in individualistic culture. The cultural differences can be explained by self-consistency, sensitivity to social consequences, parent-child interaction, and living arrangement.


Subject(s)
Culture , Interpersonal Relations , Knowledge , Parent-Child Relations , Peer Group , Adult , Analysis of Variance , Cross-Cultural Comparison , Female , Humans , Male , Republic of Korea , United States
17.
Mol Cancer Ther ; 9(6): 1894-902, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20501807

ABSTRACT

Abnormal regulation of Wnt/beta-catenin signaling followed by increased levels of the beta-catenin protein have been identified in enhanced cellular proliferation and development of colon polyps and cancers. To inhibit beta-catenin gene expression in colon cancer cells, RNA-cleaving oligodeoxyribozyme (DNAzyme) was employed to destroy the beta-catenin mRNA. We designed a strategy to identify the cleavage sites in beta-catenin RNA with a pool of random sequences from a DNAzyme library and identified four potential DNAzyme-working sites. DNAzymes were constructed for the selected target sites and were tested for the ability to cleave beta-catenin RNA. When introduced into the cells, the selected DNAzymes decreased the expression of beta-catenin significantly as well as its downstream gene, cyclin D1. Additionally, we designed short hairpin RNA that targets the same cleavage site for the selected DNAzyme. The designed short hairpin RNA also inhibited beta-catenin gene expression in colon cancer cells. Our studies show that RNA-cleaving DNAzymes and RNA interference targeted to beta-catenin significantly reduced beta-catenin-dependent gene expression, resulting in inhibition of colon cancer cell growth. These results indicate that the functional antisense oligonucleotides directed against beta-catenin might have potential as a therapeutic intervention to treat colon cancer.


Subject(s)
Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , DNA, Catalytic/metabolism , DNA, Catalytic/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Transcription, Genetic/drug effects , beta Catenin/genetics , Base Sequence , Cell Line, Tumor , Cell Proliferation/drug effects , DNA, Catalytic/genetics , Humans , Molecular Sequence Data , Nucleic Acid Conformation , RNA Interference/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/genetics , beta Catenin/metabolism
18.
J Cancer Res Clin Oncol ; 136(12): 1929-35, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20306088

ABSTRACT

PURPOSE: We evaluated the role of FDG-PET/CT in patients with metastatic gastric adenocarcinoma before palliative chemotherapy to predict prognosis and chemotherapeutic response. METHODS: The study included 35 consecutive newly diagnosed patients with metastatic gastric adenocarcinoma who underwent FDG-PET/CT before palliative chemotherapy. Maximum standardized uptake value (SUVmax) of the primary tumor was assessed to evaluate survival and chemotherapeutic response. Survival analysis was performed for time to progression and overall survival using the Kaplan-Meier method. Cox proportional hazard models were used to determine independent prognostic factors. RESULTS: All primary tumors were visualized using FDG-PET/CT (mean SUVmax = 8.1 ± 4.5, range 2.5-22.1). Sensitivity, specificity, and accuracy of FDG-PET/CT in detection of solid organ metastasis were 95.2% (20/21), 100% (14/14), and 97.1% (34/35), respectively. No significant difference of primary tumor SUVmax was found among the chemotherapeutic response groups. Univariate survival analysis demonstrated ECOG performance status (≥2), presence of solid organ metastasis, number of organs involved in distant metastasis (≥2), and SUVmax of the primary tumor (>8) as significant predictors for poor overall survival. Multivariate survival analysis showed SUVmax of the primary tumor (P = 0.048), presence of solid organ metastasis (P = 0.015), and ECOG performance status (P = 0.002) as significant independent prognostic predictors for overall survival. CONCLUSIONS: High FDG uptake of the primary tumor in patients with metastatic gastric adenocarcinoma is associated with poor overall survival. Assessment of tumor FDG uptake has limited value for prediction of chemotherapeutic response, but provides useful information regarding prognosis.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Positron-Emission Tomography/methods , Stomach Neoplasms/drug therapy , Tomography, X-Ray Computed/methods , Adenocarcinoma/diagnosis , Adult , Aged , Aged, 80 and over , Female , Fluorodeoxyglucose F18/pharmacokinetics , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Metastasis , Palliative Care/methods , Palliative Care/statistics & numerical data , Proportional Hazards Models , Reproducibility of Results , Sensitivity and Specificity , Stomach Neoplasms/diagnosis , Treatment Outcome
19.
Cancer Res Treat ; 41(2): 100-3, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19707508

ABSTRACT

We report a gastric adenocarcinoma patient with liver metastases. The metastases showed progression on computed tomography (CT), but this was not true progression in terms of metabolic activity according to (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET). Discordance between size criteria and metabolic criteria has been reported in liver gastrointestinal stromal tumors, hepatomas, and renal cell carcinomas after dramatic responses with targeted therapies such as imatinib, sorafenib, and sunitinib (1-6). However, this discordance has been rarely reported in liver metastases of gastric adenocarcinoma when treated with conventional chemotherapy.

20.
Head Neck ; 30(3): 346-50, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17972310

ABSTRACT

BACKGROUND: Although meta-analysis showed that survival improved with concurrent chemoradiation in locally advanced head and neck cancer, neoadjuvant chemotherapy is still unique, because it renders curative surgery feasible for marginally resectable head and neck cancer patients. METHODS: We reviewed patients with locally advanced head and neck cancer, who had been treated with neoadjuvant chemotherapy between June 1984 and February 2001 at the Seoul National University Hospital. RESULTS: A total of 167 patients were included. After 2 to 3 chemotherapy cycles, either surgery (38 patients) or radiation (104 patients) was conducted. Those who received surgery exhibited better survival than those who received radiation [median survival: not reached vs 33.6 months (95% CI: 22.6-44.7), p = .006]. The 5-year and 10-year survival rates of surgery group were 63.2% and 59.8%. CONCLUSION: The potential benefit of neoadjuvant chemotherapy with surgery in patients with locally advanced head and neck cancers merits further evaluation in future clinical trials.


Subject(s)
Carcinoma/mortality , Carcinoma/therapy , Head and Neck Neoplasms/mortality , Head and Neck Neoplasms/therapy , Neoadjuvant Therapy , Adolescent , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Bleomycin/administration & dosage , Carboplatin/administration & dosage , Carcinoma/pathology , Cisplatin/administration & dosage , Etoposide/administration & dosage , Female , Fluorouracil/administration & dosage , Head and Neck Neoplasms/pathology , Humans , Male , Middle Aged , Mitomycin/administration & dosage , Prognosis , Radiotherapy, Adjuvant , Survival Analysis , Vincristine/administration & dosage
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