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31.
OBJECTIVE: Adipose tissue-derived mesenchymal stem cells (ATMSCs) have been shown to differentiate into bone, cartilage, fat or muscle. However, it is not certain that ATMSCs are equal to bone marrow-derived mesenchymal stem cells (BMMSC) for their bone and cartilage forming potential. The purpose of this study was to answer the question. METHODS: BMMSCs were obtained from the medullary canal of femur and ATMSCs were isolated from the fat harvested during liposuction procedures. After cell expansion in culture media and two passages, the immunofluorescent studies for STRO-1 and CD34 were performed to characterize the BMMSCs and ATMSCs. Osteogenesis was induced on a monolayer culture with osteogenic medium containing dexamethasone, beta-glycerophosphate and ascorbate. After 2-3 weeks, alkaline phosphatase (AP) and Von Kossa staining were done. To test for chondrogenesis, mesenchymal stem cells (MSCs) were cultured in a pellet culture and in a fibrin scaffold with a chondrogenic medium (CM) containing transforming growth factor-beta(2) and insulin-like growth factor-I. After 4 weeks, Safranin-O staining and immunohistochemical staining for type II collagen were done to evaluate the chondrogenic differentiation and the matrix production. A histological scale was used to semiquantitatively assess the degree of chondrogenesis. RESULTS: Both BMMSCs and ATMSCs were STRO-1 positive and CD34 negative. On the test of osteogenesis, the osteoblastic differentiation of ATMSCs as demonstrated by AP staining was much less than that of the BMMSCs (P=0.002). The amount of matrix mineralization shown by Von Kossa staining also showed statistical differences between the two MSCs (P=0.011). On the test for chondrogenesis by the pellet culture ATMSCs showed much weaker presentation as chondrogenic cells in both cell morphology and the matrix production. The histological score was 6.5 (SD1.3) for the BMMSCs, and 4.3 (SD1.6) for the ATMSCs cultured in CM, which was statistically significant (P=0.023). The results from fibrin gel paralleled those from the pellet culture in general. CONCLUSION: The results of our study suggest that the ATMSCs may have an inferior potential for both osteogenesis and chondrogenesis compared with the BMMSCs, and these cast doubts on the value of adipose tissue as a source of MSCs.  相似文献   
32.

Purpose

The purpose of this study was to investigate the usefulness of metabolic-volumetric indices of 18F- fluorodeoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for the evaluation of neoadjuvant chemotherapy outcomes in breast cancer.

Methods

Twenty-four patients with locally advanced breast cancer were enrolled in the study. They underwent baseline 18F-FDG PET/CT scan and received four or six cycles of neoadjuvant chemotherapy, interim 18F-FDG PET/CT was done after second cycle of chemotherapy. Maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary lesions were calculated. Reduction rates of these parameters were obtained between baseline and interim 18F-FDG PET/CT. Chemotherapy outcomes were assessed using tumor size reduction rate and histological grading system (Miller and Payne system). Reduction rates of SUVmax, MTV, and TLG correlated with chemotherapy outcomes.

Results

MTV and TLG reduction rates showed significant correlation with tumor size reduction rate (R = 0.68, P = 0.0004; R = 0.62, P = 0.002, respectively). However, SUVmax reduction rate showed no significant correlation. MTV and TLG reduction rates were significantly higher in responders than nonresponders, as determined by Miller and Payne system (P < 0.0007, P < 0.002). However, SUVmax reduction rate showed no significant difference. On ROC analysis, the area under the MTV and TLG curves was 0.886, and that of SUVmax was 0.743. Sensitivity, specificity, positive predictive value, and negative predictive value to predict histopathologic response were the same for MTV and TLG, and the values were 100 %, 85.7 %, 83.3 %, and 100 %, respectively (at the reduction rate of 93.2 % for MTV, and 95.8 % for TLG).

Conclusion

Changes of metabolic–volumetric indices successfully reflected the neoadjuvant chemotherapy outcomes. MTV and TLG could be robust indices in discriminating pathologic responder as SUVmax, after neoadjuvant chemotherapy.  相似文献   
33.
A wide spectrum of pulmonary complications occurs in patients with pneumoconiosis. Those complications include chronic obstructive pulmonary disease, hemoptysis, pneumothorax, pleural disease, tuberculosis, autoimmune disease, anthracofibrosis, chronic interstitial pneumonia, and malignancy. Generally, imaging workup starts with plain chest radiography. However, sometimes, plain radiography has limited role in the diagnosis of pulmonary complications of pneumoconiosis because of overlapping pneumoconiotic infiltration. Computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI) are potentially helpful for the detection of pulmonary complications in patients with pneumoconiosis. CT, with its excellent contrast resolution, is more sensitive and specific method than plain radiograph in the evaluation of pulmonary abnormalities. CT is useful in detecting lung parenchymal abnormalities caused by infection, anthracofibrosis, and chronic interstitial pneumonia. Also, CT is valuable in distinguishing localized pneumothorax from bullae and aiding the identification of multiloculated effusions. US can be used in detection of complicated pleural effusions and guidance of the thoracentesis procedure. MRI is useful for differentiating between progressive massive fibrosis and lung cancer.  相似文献   
34.

Purpose

Lymph node (LN) characterization is crucial in determining the stage and treatment decisions in patient with lung cancer. Although 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has a higher diagnostic accuracy in LN characterization than anatomical imaging, differentiating between metastatic and inflammatory LNs is still challenging because both could show high 18F-FDG uptake. The purpose of this study was to assess if the heterogeneity of the 18F-FDG uptake could help in differentiating between inflammatory and metastatic LNs in lung cancer, and to compare with other parameters.

Methods

A total of 44 patients with adenocarcinoma of the lung, who underwent preoperative 18F-FDG PET/CT without having any previous treatments and were revealed to have 18F-FDG-avid LNs, were enrolled. There were 52 pathology-proven metastatic lymph nodes in 26 subjects. The pathology-proven metastatic LNs were compared with 42 pathology-proven inflammatory/benign LNs in 18 subjects. The coefficient of variation (CV) was used to assess the heterogeneity of 18F-FDG uptake by dividing the standard deviation of standardized uptake value (SUV) by mean SUV. The volume of interest was manually drawn based on the combined CT images of 18F-FDG PET/CT (no threshold is used). Comparisons were made with the maximum standardized uptake values (SUVmax), visual assessment of 18F-FDG uptake, longest diameter, and maximum Hounsfield units (HUmax).

Results

Metastatic lymph nodes tended to have higher CVs than the inflammatory LNs. The mean CV of metastatic LNs (0.30 ± 0.08; range: 0.08–0.55) was higher than that of inflammatory LNs (0.17 + 0.06; range, 0.07–0.32; P < 0.0001). On receiver operating characteristic (ROC) curve analysis, the area under curve was 0.901, and using 0.20 as cut-off value, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 88.5 %, 76.2 %, 82.2 %, 84.3, and 83.0 % respectively. Accuracy of CV was slightly higher than SUVmax and diameter, but significantly higher than visual assessment and HUmax.

Conclusions

In patients with adenocarcinoma of the lung having no prior treatments, metastatic LNs showed more heterogeneous 18F-FDG uptake than inflammatory LNs. Measuring the CV of the SUV derived from a manual volume of interest (VOI) can be helpful in determining metastatic LN of adenocarcinoma of the lung. Including diagnostic criteria of CV into the diagnostic approach can increase the accuracy of mediastinal node status.  相似文献   
35.
Purpose Motion artifact is problematic in the diagnosis of Creutzfeldt-Jakob disease (CJD) because of dementia. The purpose was to compare the occurrence of this artifact between a diffusion-weighted (DW) magnetic resonance (MR) imaging sequence and conventional sequences. Materials and methods Ten MR examinations comprising T2-weighted, T1-weighted, DW, and fluid-attenuated inversion recovery imaging in seven CJD patients were retrospectively evaluated. The occurrence of motion artifacts on each sequence were assessed, and the examination was classified into four groups as follows: group A, motion artifact not revealed on DW imaging but revealed on one or more other sequences; group B, revealed on DW imaging and one or more other sequences; group C, not revealed on any sequences; and group D, revealed on DW imaging but not on any other sequences. Results The 10 MR examinations were classified as eight group A (80%), one B (10%), one C (10%), and zero D (0%). Conclusion Motion artifacts are likely to occur in any conventional imaging sequences in CJD, but the fast-imaging ability of DW imaging can reduce this artifact. The combination of an absence of motion artifact on DW imaging and the presence on conventional sequences may be one of the frequent findings of CJD.  相似文献   
36.
甲状腺术后瘢痕组织是甲状腺局部分切除术后由于手术方式及缝线填充而形成的组织,甲状腺术后瘢痕组织形成及其发生发展过程同一般的组织损伤修复病理过程一样,为渐进老化阶段的结缔组织,其内小血管稀少,胶原纤维增多[1]。由于甲状腺术后瘢痕组织其质地较硬,活动性差,超声声像图上表现缺乏典型特征,与癌灶极其相似,因此鉴别较困难。本文将介绍超声对于甲状腺术后的随诊应用,分析甲状腺术后瘢痕组织的超声检查特点并着重介绍超声动态观察甲状腺术后瘢痕组织的应用及其发展前景。  相似文献   
37.
The aims of this study were to establish reference data for bone mineral density (BMD) at central skeletal sites using Lunar dual-energy X-ray absorptiometry (DXA), and to estimate the age-and sex-specific prevalence of osteoporosis in a Korean population. We performed a population-based, cross-sectional study. The subjects were 4148 (1810 men and 2338 women) Korean adults, aged 20–79 years. The BMD for central sites (lumbar spine, femoral neck, trochanter, and Ward’s triangle) were measured by DXA. The standardized prevalence of osteoporosis among individual aged 50–79 years in lumbar spine, femoral neck, Ward’s triangle, and trochanter was 40.1%, 12.4%, 28.4%, and 4.4% in women and 6.5%, 5.9%, 3.7%, and 1.6% in men, respectively. In women, peak BMD occurred in the age range 40–49 years for the femoral neck and trochanter, 30–39 years for the lumbar spine, and 20–29 years for Ward’s triangle. In men, peak BMD values were observed at 20–29 years for all measured sites. This study establishes a normative database for BMD at central skeletal sites using dualenergy X-ray absorptiometry and provides more reliable information on the prevalence of osteoporosis in Korea.  相似文献   
38.
39.
目的 评价吡柔比星(THP)膀胱灌注预防腺性膀胱炎术后复发的疗效。方法 对30例腺性膀胱炎患者行经尿道汽化电切术,术后定期应用THP(40mg/50ml)膀胱内灌注化疗。结果 30例患者随访5~20个月,平均14.5个月,3例复发(10%)。未见有全身性药物不良反应,仅2例血白细胞降至3000个/ml。结论THP膀胱灌注预防腺性膀胱炎术后复发疗效满意,病人耐受性好,副作用小。  相似文献   
40.
舌黏膜尿道成形治疗尿道狭窄的初步报告   总被引:3,自引:0,他引:3  
目的:探讨舌黏膜补片法尿道成形治疗尿道狭窄的疗效。方法:采用舌黏膜尿道成形治疗尿道狭窄14例。尿道狭窄段3.5~14cm,平均6.2cm;术前耻骨上膀胱造瘘8例,余6例排尿均较为困难,最大尿流率2.5~5.5ml/s,平均3.8ml/s。结果:术后随访2~8个月,1例因伤口感染致尿道皮肤瘘,余患者均排尿通畅,最大尿流率增至22~51ml/s,平均29.6ml/s。结论:舌黏膜具有取材方便、对患者创伤小、抗感染力强等特点,是一种较好的尿道替代物,尤其适合尿道狭窄段<6cm的患者。  相似文献   
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