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91.
Mi Sook Gwak Kwang-Woong Lee Shi Yeon Kim Jihyun Lee Jae Won Joh Sung Joo Kim Hwan Hyo Lee Jean Wan Park Gaab Soo Kim Suk-Koo Lee 《Liver transplantation》2005,11(3):331-335
During liver transplantation for hepatocellular carcinoma (HCC) patients, HCC could theoretically be introduced into the systemic circulation when salvaged blood is used with an autotransfusion device. Several reports have shown that some types of leukocyte depletion filters (LDFs) could completely reduce the risk for reintroducing some types of tumor cells. In this study, we tested the ability of the LDF (RCEZ1T, Pall Biomedical Co, NY, USA) to reduce the risk for reintroducing HCC cells in vitro by using a very sensitive detection method. We divided the test group into 6 groups: group I was 10 cells, group II was 20 cells, group III was 2 x 10(3) cells, group IV was 2 x 10(5) cells, group V was 2 x 10(6) cells, and group VI was 2 x 10(7) cells. The counted cells in 200 mL saline were passed through the RCEZ1T using the force of gravity. To identify the presence of cells, the pellet was resuspended, and polymerase chain reaction (PCR) was performed. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a housekeeping gene, was used as a primer. In groups I and II, the HCC cells were completely filtered in all experiments. However, in groups III, IV, and V, the HCC cells were not completely filtered in a few of the repeated experiments, with the unfiltered rate of tumor cells being between 8% and 20%. In group VI, the HCC cells were not completely filtered in all the repeated experiments. In conclusion, the RCEZ1T filter markedly reduced the risk for reintroduction of HCC cells. However, at high HCC cell load the filter cannot completely remove all the tumor cells. Further studies are required to assess the impact in clinical settings. 相似文献
92.
Matrix metalloproteinases in ascending aortic aneurysms: bicuspid versus trileaflet aortic valves 总被引:3,自引:0,他引:3
LeMaire SA Wang X Wilks JA Carter SA Wen S Won T Leonardelli D Anand G Conklin LD Wang XL Thompson RW Coselli JS 《The Journal of surgical research》2005,123(1):40-48
BACKGROUND: Abnormal matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) expression contributes to the development of abdominal aortic aneurysms. Recent data suggest that MMP-2 and MMP-9 may also play a role in thoracic aortic disease. We sought to determine (1) whether ascending aortic aneurysms are associated with increased MMP expression and (2) whether aortic inflammation and MMP expression differ between patients with congenital bicuspid aortic valves (BAVs) and those with trileaflet aortic valves (TAVs). MATERIALS AND METHODS: Samples of ascending aortic aneurysms were obtained from 29 patients; 14 patients had BAVs and 15 had TAVs. Control ascending aorta was obtained from 14 organ donors or heart transplant recipients. Aortic histology and immunohistochemistry were performed to evaluate elastin degradation, inflammatory changes, and MMP-2 and MMP-9 expression. Aortic levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured using ELISA. RESULTS: Aneurysms in the TAV patients exhibited marked inflammation, high CD68 expression, diminished elastin content, increased MMP-9 expression, and normal MMP-2 levels. In contrast, BAV aneurysms were characterized by a relative lack of inflammation, preservation of elastin content, normal MMP-9 levels, and elevated MMP-2 expression. TIMP-1 and TIMP-2 levels were not significantly different among the three groups. CONCLUSIONS: Ascending aortic aneurysms exhibited increased MMP expression. The pattern of MMP expression and the degree of inflammation, however, differed between aneurysms associated with BAVs and those with TAVs. Variations in the molecular mechanisms underlying different types of thoracic aortic aneurysms warrant further investigation. 相似文献
93.
94.
Hun Cho Jin Woo Kim You Sun Hong Sang Hyun Lim Je Hwan Won 《Korean journal of radiology》2015,16(4):723-728
ObjectiveThis study was conducted to evaluate stent compression in iliac vein compression syndrome (IVCS) and to identify its association with stent patency.ResultsAll of the stents used were laser-cut nitinol stents. The proportion of limbs showing significant stent compression was 33%. Fifty-six percent of limbs in the significant stent compression group developed stent occlusion. On the other hand, only 9% of limbs in the insignificant stent compression group developed stent occlusion. Significant stent compression was inversely correlated with stent patency (p < 0.001). The median patency period evaluated with Kaplan-Meier analysis was 20.0 months for patients with significant stent compression. Other factors including gender, age, and type of stent were not correlated with stent patency. Significant stent compression occurred most frequently (87.5%) at the upper end of the stent (ilio-caval junction).ConclusionSignificant compression of nitinol stents placed in IVCS highly affects stent patency. Therefore, in order to prevent stent compression in IVCS, nitinol stents with higher radial resistive force may be required. 相似文献
95.
Jeong Won Lee Hye Sook Min Sang Mi Lee Hyun Woo Kwon June-Key Chung 《Nuclear Medicine and Molecular Imaging》2015,49(2):127-134
Purpose
The aim of this study was to investigate relationships between the immunohistochemical results and radioiodine scan and 18F-FDG PET findings in papillary thyroid cancer (PTC) patients with recurrent cervical nodal metastases.Methods
A total of 46 PTC patients who had undergone a radioiodine scan and/or 18F-FDG PET/CT and a subsequent operation on recurrent cervical lymph nodes were enrolled. Twenty-seven patients underwent 18F-FDG PET/CT, 8 underwent radioiodine scans, and 11 underwent both scans. In all surgical specimens, the immunoexpressions of thyroglobulin (Tg), sodium-iodide symporter (NIS), glucose transporter 1 (Glut-1), and somatostatin receptor 1 and 2A (SSTR1 and SSTR2A) were assessed, and associations between these expressions and radioiodine scan and 18F-FDG PET findings were evaluated.Results
Of the 38 patients who underwent 18F-FDG PET/CT, all patients with weak Tg expression had positive 18F-FDG uptake, while only 45 % of the patients with moderate or strong Tg expression showed positive uptake (p = 0.01). The proportion of patients with positive 18F-FDG uptake increased as the degree of Glut-1 expression with luminal accentuation increased. Of the 19 patients who underwent a radioiodine scan, the proportion with positive radioiodine uptake was greater among patients with strong NIS and SSTR2A expression than among patients expressing these markers at weak levels (p = 0.04 for all). All three patients with weak Tg expression were negative for radioiodine uptake.Conclusion
The 18F-FDG uptakes of recurrent cervical nodes are related to strong Glut-1 expression with luminal accentuation and weak Tg expression, whereas radioiodine uptake is related to the strong expressions of NIS and SSTR2A. 相似文献96.
Bum-Jin Shim Heejae Won Shin-Yoon Kim Seung-Hoon Baek 《World journal of orthopedics》2023,14(5):302-311
The atypical femoral fracture (AFF) has been attracting significant attention because of its increasing incidence; additionally, its treatment is challenging from biological and mechanical aspects. Although surgery is often required to manage complete AFFs, clear guidelines for the surgical treatment of AFFs are currently sparse. We reviewed and described the surgical treatment of AFFs and the surveillance of the contralateral femur. For complete AFFs, cephalomedullary intramedullary nailing spanning the entire length of the femur can be used. Various surgical techniques to overcome the femoral bowing common in AFFs include a lateral entry point, external rotation of the nail, and the use of a nail with a small radius of curvature, or a contralateral nail. In the case of a narrow medullary canal, severe femoral bowing, or pre-existing implants, plate fixation may be considered as an alternative. For incomplete AFFs, prophylactic fixation depends on several risk factors, such as a subtrochanteric location, presence of a radiolucent line, functional pain, and condition of the contralateral femur; the same surgical principles as those in complete AFFs can be applied. Finally, once AFF is diagnosed, clinicians should recognize the increased risk of contralateral AFFs, and close surveillance of the contralateral femur is recommended. 相似文献
97.
Yong Seuk Lee Beom Koo Lee Won Seok Kim Jang Seok Choi Jong Ryoon Baek Chan-Woong Moon 《Knee surgery, sports traumatology, arthroscopy》2014,22(11):2629-2634
Purpose
The objectives of this study were (1) to evaluate the sagittal and coronal plane location of the popliteal artery during the advancement of open-wedge high tibial osteotomy and (2) to confirm the effect of osteoarthritis if it changes the relationship between the popliteal artery and posterior cortex.Methods
Two hundred consecutive patients were enrolled, and we divided patients into two subgroups according to age and cartilage status in the radiologic report of magnetic resonance imaging (group I: 100 non-arthritic knees; group II: 100 arthritic knees). For prediction of the location of the popliteal artery during the operation, sagittal and coronal plane location along the osteotomy plane was evaluated.Results
The distance between the posterior cortex of the osteotomy and popliteal artery was 13–14 mm on the sagittal plane, and the popliteal artery was located at an approximately 35 ± 5.5 mm portion from the starting point of the osteotomy on the coronal plane. The distance at the starting point of osteotomy was larger than at the end portion and prominent area. In comparison between groups I and II, group II showed a larger distance on the sagittal planes [osteotomy–vascular: 13.6 vs 14.4 (p = 0.01), fibula–vascular: 4.88 vs 6.5 (p < 0.01), and prominence–vascular: 4.3 vs 5.3 (p < 0.01)] compared to the group I.Conclusions
Special caution and some protection should be given until the approximately 35 mm portion from the starting point of the posteromedial cortex with consideration for the approximity on the sagittal plane. In comparison between the non-arthritic and arthritic knee, differences were observed on the sagittal plane. However, the value was minimal, and the clinical relevance was questionable.Level of evidence
Case series, Level IV. 相似文献98.
Image quality assessment of ultra low-dose chest CT using sinogram-affirmed iterative reconstruction
So Won Lee Yookyung Kim Sung Shine Shim Jeong Kyong Lee Seok Jeong Lee Yon Ju Ryu Jung Hyun Chang 《European radiology》2014,24(4):817-826
Objectives
To assess the image quality of ultra-low-dose computed tomography (ULDCT) using sinogram-affirmed iterative reconstruction (SAFIRE) compared to reduced dose CT (RDCT).Methods
Eighty-one consecutive patients underwent non-enhanced ULDCT using 80 kVp and 30 mAs and contrast-enhanced RDCT using automated tube potential selection and tube current modulation. CT images were reconstructed with SAFIRE. Image noise and subjective image quality of normal structures and various pulmonary lesions were assessed.Results
The mean effective doses were 0.29?±?0.03 and 2.88?±?1.11 mSv for ULDCT and RDCT, respectively. ULDCT had significantly higher noise (p?<?0.001). Image quality of five normal structures was diagnostic in 91.1 % of ULDCT and 100 % of RDCT. With ULDCT, the frequencies of non-diagnostic image quality were 2.0 (1/50), 4.6 (13/280), 25.5 (14/55), and 40.0 (8/20)% for BMIs of?<?20, 20–25, 25–30, and >30. In the assessment of pulmonary lesions, non-diagnostic image quality was observed for 11.2 % of all lesions, 60.9 % of decreased attenuation (significantly more frequent for upper lung lesions), and 23.5 % of ground-glass nodules.Conclusion
ULDCT generates diagnostic images in patients with a BMI ≤25, but is of limited use for lesions with decreased attenuation, ground-glass nodules, or those located in the upper lobe.Key Points
? Iterative reconstruction enables ultra-low-dose CT (ULDCT) with very low radiation doses. ? Image quality of ULDCT depends on the patient body mass index (BMI). ? Selection of kVp and mAs depends on both BMI and lesion type. ? Diagnosis of pulmonary emphysema or ground-glass nodules requires higher radiation doses. 相似文献99.
Jiwon An Youn-Woo Lee Woo Young Park Sungchul Park Hyungbae Park Ji Won Yoo Jong Bum Choi 《Journal of anesthesia》2016,30(6):999-1002
Purpose
Anatomic variations complicate surface landmark-guided needle placement, thereby increasing nerve blockade failure rate. However, little is understood about how anatomic distances change under different clinical conditions. As the cricoid cartilage is an easy and accurate landmark, we investigated changes in distance between the sixth or seventh cervical transverse processes (C6TP or C7TP) and the cricoid cartilage in neutral and extended supine positions.Methods
Forty-two patients (16 men, 26 women) were included in this study. Distances between the cricoid cartilage and C6TP/C7TP were measured using ultrasonography with the patient in neutral and extended supine positions.Results
C6TP and C7TP were caudally located at 6.0 ± 8.1 and 15.1 ± 7.2 mm, respectively, from the cricoid cartilage in the neutral supine position, and at 15.2 ± 8.0 and 25.3 ± 8.0 mm, respectively, in the extended supine position. In the extended supine position, the cricoid cartilage was more cephalad than C6TP and C7TP in all patients. The distance from the cricoid cartilage to C6TP was 12.1 ± 7.6 mm in men and 17.2 ± 7.7 mm in women.Conclusion
C6TP and C7TP are located approximately 15 and 25 mm, respectively, caudal to the cricoid cartilage in the extended supine position. Our results highlight the fact that there can be significant anatomic variation between the extended and neutral supine positions used in stellate ganglion block, which should be kept in mind when devising easily identifiable and palpable surface landmarks.100.
Min Ji Shin Harin Rhee Il Young Kim Sang Heon Song Dong Won Lee Soo Bong Lee Ihm Soo Kwak Eun Young Seong 《Clinical and experimental nephrology》2016,20(3):402-410