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91.
Yoon J. Lee Seung E. Baek Sujin Lee Yeon J. Jeong Ki J. Kim Young J. Jun Jong W. Rhie 《International wound journal》2019,16(1):286-296
The potential use of extracellular matrix (ECM) as a source of wound dressing material has recently received much attention. The ECM is an intricate network of various combinations of elastin, collagens, laminin, fibronectin, and proteoglycans that play a key role in stimulating cell proliferation and differentiation. We evaluated the efficacy of an ECM sheet derived from human adipose tissue as a wound dressing material to enhance healing. We prepared a novel porous ECM sheet dressing scaffold from human adipose tissue. in vitro analysis of the ECM sheets showed efficient decellularisation; absence of immunostimulatory components; and the presence of a wide number of angiogenic and bioactive factors, including collagen, elastin, and proteoglycans. To evaluate in vivo efficacy, full‐thickness excisional wounds were created on the dorsal skin of a rat, and the ECM sheets; secondary healing foam wound dressing, Healoderm; or a conventional dressing were applied to each wound site. Photographs were taken every other day, and the degree of reepithelialisation of the wounds was determined. Application of an ECM sheet dressing enhanced the macroscopic wound‐healing rate on days 4, 7, and 10 compared with that in the control group. Microscopic analysis indicated that the reepithelialisation rate of the wound was higher in the ECM group compared with that in the control group; the reepithelialisation rate was better than that of the secondary healing foam wound dressing. Moreover, a denser and more organised granulation tissue was formed in the ECM sheet group compared with that in the secondary healing foam wound dressing and control groups. The ECM sheet also showed the highest microvessel density compared with the secondary healing foam wound dressing and control groups. Based on these data, we suggest that a bioactive ECM sheet dressing derived from human adipose can provide therapeutic proteins for wound healing. 相似文献
92.
Sung Rak Lee Hyoung Won Jang Dhong Won Lee Sang Wook Nam Jeong Ku Ha Jin Goo Kim 《Clinics in Orthopedic Surgery》2013,5(3):188-194
Background
The purpose of this study is to report a modified transtibial technique to approach the center of anatomical femoral footprint in anterior cruciate ligament (ACL) reconstruction and to investigate the accurate femoral tunnel position with 3-dimensional computed tomography (3D-CT) and radiography after reconstruction.Methods
From December 2010 to October 2011, we evaluated 98 patients who underwent primary ACL reconstruction using a modified transtibial technique to approach the center of anatomical femoral footprint in single bundle ACL reconstruction with hamstring autograft. Their femoral tunnel positions were investigated with 3D-CT and radiography postoperatively. Femoral tunnel angle was measured on the postoperative anteroposterior (AP) radiograph and the center of the femoral tunnel aperture on the lateral femoral condyle was assessed with 3D-CT according to the quadrant method by two orthopedic surgeons.Results
According to the quadrant method with 3D-CT, the femoral tunnel was measured at a mean of 32.94% ± 5.16% from the proximal condylar surface (parallel to the Blumensaat line) and 41.89% ± 5.58% from the notch roof (perpendicular to the Blumensaat line) with good interobserver (intraclass correlation coefficients [ICC], 0.766 and 0.793, respectively) and intraobserver reliability (ICC, 0.875 and 0.893, respectively). According to the radiographic measurement on the AP view, the femoral tunnel angles averaged 50.43° ± 7.04° (ICC, 0.783 and 0.911, respectively).Conclusions
Our modified transtibial technique is anticipated to provide more anatomical placement of the femoral tunnel during ACL reconstruction than the former traditional transtibial techniques. 相似文献93.
Jeong HJ Min JJ Park JM Chung JK Kim BT Jeong JM Lee DS Lee MC Han SK Shim YS 《Nuclear medicine communications》2002,23(9):865-870
The aim of this study was to determine whether quantitative information obtained from [(18)F]fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has a prognostic significance for patients with non-small cell lung cancer (NSCLC). We investigated (18)F-FDG PET imaging of 73 patients with NSCLC. The maximum standardized uptake value (SUV(max)) was significantly different between the histopathological types of tumour (squamous cell carcinoma (n=37, 12.4+/-5.1), adenocarcinoma (n=30, 8.2+/-5.8), bronchioloalveolar carcinoma (n=4, 2.6+/-1.7), <0.01). In the univariate analysis of all patients, staging (P=0.0001), tumour cell type (P=0.013), and a SUV(max) greater than 7 (P=0.0011) was correlated with survival. However, a multivariate analysis identified staging and SUV(max) greater than 7 were affected survival adversely. The mortality rate of patients with group I disease (stage I to stage IIIA) was 5.8 times lower than that of patients with group II disease (stage IIIB to stage IV). Patients with a high SUV(max) (> or =7) had a 6.3 times higher mortality than those with a low SUV(max)(<7). By multivariate analysis of patients with squamous cell carcinoma, only grouping affected survival (P=0.008, relative risk=4.3). In the case of adenocarcinoma, the SUV(max) (>10) correlated exclusively with poorer survival (P=0.031, relative risk=11.152). (18)F-FDG uptake correlated with survival in NSCLC. Especially in adenocarcinomas, the SUV(max) was complementary to other known prognostic factors. 相似文献
94.
Neuronal tumors of the central nervous system: radiologic findings and pathologic correlation. 总被引:17,自引:0,他引:17
Ji Hoon Shin Ho Kyu Lee Shin Kwang Khang Dong Won Kim Ae Kyung Jeong Kook Jin Ahn Choong Gon Choi Dae Chul Suh 《Radiographics》2002,22(5):1177-1189
Pure neuronal and mixed neuronal-glial tumors of the central nervous system are uncommon but fascinating because they are less aggressive than the more common glial tumors and their prognosis is excellent. Neurologic manifestations are varied and include seizures, symptoms of increased intracranial pressure, and neurologic deficits according to tumor location. Many neuronal tumors of the central nervous system demonstrate characteristic radiologic findings. At magnetic resonance (MR) imaging, gangliocytomas demonstrate low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, and frequent enhancement on gadolinium-enhanced T1-weighted images. Characteristic MR imaging findings of Lhermitte-Duclos disease are a nonenhancing mass in a cerebellar hemisphere with a striated pattern. Central neurocytomas are typically located in the lateral ventricles near the foramen of Monro with a characteristic attachment to the septum pellucidum. Ganglioneurocytoma is a rare variant of central neurocytoma that is characterized by differentiation toward ganglion cells. In ganglioglioma, a well-defined cystic mass with a solid mural nodule is typically seen. Extension of enhancement to the leptomeninges is characteristic of desmoplastic infantile ganglioglioma and correlates with the firm dural attachment of the solid component. Dysembryoplastic neuroepithelial tumor has a well-demarcated, multilobulated or gyriform appearance. 相似文献
95.
Reduction of flow-related signal loss in flow-compensated 3D TOF MR angiography, using variable echo time (3D TOF-VTE). 总被引:1,自引:0,他引:1
Eun-Kee Jeong Dennis L Parker Jay S Tsuruda Jong-Yun Won 《Magnetic resonance in medicine》2002,48(4):667-676
High-resolution MRA with phase/frequency flow compensation may require very long echo times (TEs). Variable TE (VTE) was implemented into flow-compensated 3D TOF to minimize the effective TE and reduce the flow-related signal void. The k-space of the 3D TOF was divided into segment groups ranging from two to 32 segments with different TEs. The TEs were minimized and the flow-compensation gradient lobes were calculated to null the total first moment at the peak of the echo for each segment. Possible artifacts and off-resonance effects were evaluated, with respect to the number of TE segments, using the point spread function (PSF) and corresponding experiments. The optimal number of TE segments for the least artifact was determined to be one-half of the number of slices. Two types of artifacts caused by VTE were predicted and subsequently observed. The developed pulse sequence 3D TOF-VTE was tested on clinical MRI systems, by performing scans of the cervical carotid artery and intracranial carotid artery at the carotid siphon. The signal distribution near the bifurcation and the siphon was much more uniform with VTE, and the flow-related signal loss was greatly reduced. The resultant MR angiograms provided improved vessel detail. The results show that VTE improved the quality of flow-compensated 3D TOF MRA. 相似文献
96.
PURPOSE: Increasing clinical importance is being placed on the role of differential renal function (DRF) in the management of congenital ureteropelvic junction obstruction. Supranormal DRF of the hydronephrotic kidney on renal scan is a puzzling phenomenon and is hypothesized to be due to an increase in single nephron filtration or nephron volume without sound evidence. We studied the histopathological changes of hydronephrotic kidneys to determine whether glomerular hypertrophy underlies supranormal DRF. MATERIALS AND METHODS: We retrospectively evaluated the records of 3 females and 32 males with unilateral congenital hydronephrosis who underwent pyeloplasty. Mean patient age at operation was 12.6 months (range 0.1 to 144). Needle biopsies from 3 different sites at the lower pole of the kidney were performed during surgery. To evaluate the presence of glomerular hypertrophy, the maximal planar area of glomeruli was measured under light microscopy using an image analyzer. Tissue samples obtained from kidneys without a history of urinary tract disease at autopsy were used as controls. The mean glomerular areas of the patient and control groups were evaluated according to DRF and age. RESULTS: The mean glomerular area values of the patient group were smaller than those of the control group, except for 4 patients. The glomerular areas of the hydronephrotic kidneys with supranormal DRF were not significantly different from those of the control group. Instead, the probability of larger renal glomeruli increased with decreasing DRF (p = 0.1155). CONCLUSIONS: Increased nephron volume can be discounted as a cause of supranormal DRF. 相似文献
97.
Shawn T. Steen MD Alice P. Chung MD Soo-Hwa Han MD Arnold L. Vinstein MD Jeong L. Yoon MS Armando E. Giuliano MD 《Annals of surgical oncology》2013,20(2):633-639
Background
Preoperative assessment of the nipple–areolar complex (NAC) is invaluable when considering nipple-sparing mastectomy. Our hypothesis is that breast magnetic resonance imaging (MRI) may predict involvement of the NAC with tumor.Methods
Clinical, histopathologic, and imaging data were compiled for patients who underwent preoperative breast MRI followed by mastectomy or nipple-sparing mastectomy for malignancy between 2006 and 2009. Blinded rereview of all MRI studies was performed by a breast MRI imager and compared to initial MRI findings. Multivariate analysis identified variables predicting NAC involvement with tumor.Results
Of 77 breasts, 18 (23 %) had tumor involving or within 1 cm of the NAC. The sensitivity of detecting histopathologically confirmed NAC involvement was 61 % with history and/or physical examination, and 56 % with MRI. Univariate analysis identified the following variables as significant for NAC involvement: large tumors near the nipple on preoperative MRI, node-positive disease, invasive lobular carcinoma, advanced histopathologic T stage, and neoadjuvant chemotherapy. On multivariate analysis, only tumor size >2 cm and distance from tumor edge to the NAC <2 cm on MRI maintained significance. Pearson correlation coefficient for MRI size compared to histopathologic size was 0.53 (P < 0.0001).Conclusions
MRI is not superior to thorough clinical evaluation for predicting tumor in or near the NAC. However, MRI-measured tumor size and distance from the NAC are correlated with increased risk of NAC involvement. The combination of preoperative history and physical examination, tumor characteristics, and breast MRI can aid the surgeon in predicting a tumor-involved nipple more than any single modality alone. 相似文献98.
Background
Knowledge of the intraoperative location of lesions is a prerequisite for deciding the proper extent of gastric resection or the choice of anastomosis technique during totally laparoscopic distal gastrectomy (TLDG) for early gastric cancer (EGC). In this study we introduce a novel tumor localization method for TLDG: endoscopic blood tattooing.Methods
Twenty-three consecutive patients scheduled for TLDG for EGC were enrolled in this prospective study. The day before surgery, 2–3?ml of autologous blood was injected into the gastric muscle layer at 3–4?cm proximal to the lesion during endoscopy.Results
The study subjects consisted of 15 males and 8 females with a mean age of 61?±?10.4?years. During surgery, the endoscopic blood tattooed sites were successfully identified in all 23 patients. No complications associated with the procedure occurred, and no patient had microscopic residual tumor cells at the proximal resection margin, with a mean proximal margin length of 3.3?±?2.7?cm. Eighteen patients underwent TLDG with Billroth II anastomosis, four patients with Roux-en-Y gastrojejunostomy, and one patient with laparoscopic total gastrectomy. At final pathologic examinations, 20 patients were of stage IA and 3 were of stage IB according to the UICC TNM classification (6th ed.).Conclusions
Endoscopic blood tattooing provides a simple and useful means of localizing lesions during TLDG for EGC. Although the superiority of this technique over other localization methods needs to be evaluated further, the authors recommend endoscopic blood tattooing as an alternative to other intraoperative localization methods for laparoscopic surgery for EGC. 相似文献99.
We investigated the therapeutic effect of topical Risedronate (RIS) on a mouse model of estrogen-deficient osteoporosis. Fourteen-week-old female mice were ovariectomized and assigned to 4 groups: SHAM-operated (SHAM), OVX mice treated with vehicle (OVX-V), OVX mice treated with 0.2% RIS (OVX-0.2% RIS), and OVX-mice treated with 0.02% RIS (OVX-0.02% RIS). Topical samples containing RIS were prepared in 10% (w/w) polyethylene glycol (PEG, MW 400) and 80 μg of sample was spread on the mice's mid-backs every 3 days for 5 weeks. Micro-CT analysis of femora demonstrated that OVX-0.2% RIS exhibited a 29% greater bone mineral density and 24% greater bone volume fraction than that of OVX-V group. Investigation of the trabecular bone in OVX-0.2% RIS revealed a 24% higher bone volume (BV/TV), 51% higher trabecular number (Tb.N), and 40% lower trabecular separation (Tb.Sp) compared to OVX-V mice. Additionally, bone phenotypes of tibiae were further confirmed by histological analysis. OVX-0.2% RIS group exhibited a 494% greater BV/TV, 464% less Tb.Sp, 81% greater active osteoclast surface (Oc.S/BS) and 26% less osteoclast number (N.Oc/BS) than that of OVX-V group. Collectively, these results indicated that topical delivery of RIS has powerful pharmaceutical effects on the prevention of osteoporosis and bone turnover. 相似文献
100.
In Gab Jeong Dalsan You Jongwon Kim Seong Cheol Kim Jun Hyuk Hong Hanjong Ahn Choung-Soo Kim 《World journal of urology》2012,30(6):815-820