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81.
Park JC  Lee SM  Kim JC  Yun JH  Cho KS  Im GI  Kim BS  Kim CS 《Oral diseases》2012,18(6):537-547
Oral Diseases (2012) 18, 537–547 Objective: The human periodontal ligament stem cells (hPDLSCs) and human alveolar bone–derived stromal cells (hABCs) seem to be closely involved in the maintenance of alveolar bone in an anatomically indirect manner; however, there is little study on this matter. Therefore, the effect of hPDLSCs on the osteoclastogenic, osteogenic, and adipogenic differentiation of hABCs was evaluated, focusing on the humoral factors released by hPDLSCs. Materials and methods: Human periodontal ligament stem cells and hABCs were isolated and characterized. hPDLSCs were indirectly cocultured to observe the in vitro effect of humoral factors released from hPDLSCs on the osteoclastogenic, osteogenic, and adipogenic differentiation of hABCs. Human gingival fibroblasts (hGFs) were utilized as positive control. Results: Isolated cells demonstrated the presence of stem cells within. Indirect coculture of hPDLSCs greatly inhibited osteoclastogenesis by hABCs. Osteogenesis/adipogenesis of hABCs was also inhibited by indirect coculture with hPDLSC. The magnitude of regulatory effect from hPDLSCs was significantly greater than that of hGFs. Conclusions: Humoral factors released from hPDLSCs seemed to modulate the differentiation of hABCs, and the osteoclastogenic, osteogenic, and adipogenic differentiation of hABCs was all inhibited, suggesting the potential role of hPDLSCs in the maintenance of the alveolar bone.  相似文献   
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Objective Chemerin, a recently discovered adipocytokine, may be linked to obesity and obesity‐associated metabolic complications. However, the relationship between visceral fat accumulation and chemerin is still unknown. Therefore, we investigated the relationship between serum chemerin levels and body composition as measured by computed tomography (CT). Patients We recruited 173 men and women without histories of diabetes or cardiovascular disease. Measurements Biomarkers of metabolic risk factors and body composition by computed tomography were assessed. Serum chemerin levels were measured by enzyme‐linked immunosorbent assay. Results Chemerin levels correlated with body mass index (BMI), waist circumference, abdominal visceral fat area, blood pressure, fasting insulin, homoeostasis model of assessment‐insulin resistance, total cholesterol, triglyceride, creatinine, aspartate aminotransferase and alanine aminotransferase. By stepwise multiple regression analysis, abdominal visceral fat area, blood pressure and total cholesterol levels independently affected chemerin levels. Conclusions Abdominal visceral fat accumulation, blood pressure and lipid profile were significantly associated with serum chemerin levels. Our findings suggest that chemerin may be a mediator that links visceral obesity to cardiovascular risk factors.  相似文献   
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Central pulse pressure is correlated with carotid atherosclerosis and the incidence of cardiovascular events more significantly than brachial pulse pressure. Augmentation index (Aix) has been shown to be an independent predictor of cardiovascular morbidity and mortality. Pulse wave analysis using the Gaon system allows for the estimation of central blood pressure (CBP), corrected augmentation index (Aix@HR75), ejection duration (ED) and subendocardial viability ratio (SEVR), and is widely used in clinical research in Korea. However, the accuracy of this system is controversial. From February 2008 to March 2011, 99 patients were recruited for this study. Measurements were taken both by the Gaon system and the SphygmoCor system on the same day for all study participants. The estimated values of CBP, Aix@HR75, ED and SEVR for the two systems were compared using paired t-tests, simple correlation analyses and Bland-Altman plots. Systolic blood pressure (SBP) estimated by the two systems was significantly (P<0.001) correlated; the coefficient was 0.982. The two s.d. of the difference in SBP between these systems was quite small--<7?mm?Hg. Aix@HR75, ED and SEVR as estimated by the two systems were also significantly correlated, although they, especially SEVR, showed much weaker correlations than were observed in SBP: coefficients for Aix@HR75, ED and SEVR were 0.727, 0.648 and 0.230, respectively. We assessed the CBP of Korean patients estimated by the two systems and observed that the correlations of Aix, ED and SEVR were weaker than that of CBP. Such variations may be due to the difference in measuring methods between the devices. As even a slight change in pulse waveforms may result in a large difference in estimations, parameters, including Aix@HR75, ED and SEVR, should be carefully interpreted by experienced clinicians.  相似文献   
86.
Using granulocyte-macrophage colony stimulating factor, interleukin4 and tumor necrosis factor α, we generated dendritic cells (DCs) from mononuclear cells isolated from the peripheral blood (PB) of eight patients with acute lymphoblastic leukemia (ALL), who were in complete remission (CR), and pulsed these DCs with leukemic cell lysates. Specific cytotoxicity assays were performed by incubation of effector cells (lymphocytes generated from cryopreserved mononuclear cells isolated in CR state of ALL) and targets (cryopreserved leukemic cells at diagnosis). Patients showing decreased cytotoxicity had poorer clinical courses. When we measured lymphocyte subsets, we found positive correlations between cytotoxicity levels and the proportions of T lymphocytes and CD8+ T lymphocytes, but negative correlations between cytotoxicity levels and the proportions of NK cells and regulatory T lymphocytes. In conclusion, we show here that leukemia-specific autologous DCs can be generated from the PB of ALL patients in CR, that the incubation of these DCs with leukemic cell lysates can generate lymphocytes potentiated against leukemic cells, and that relationships are evident among all of cytotoxicity, lymphocyte subsets, and patient prognosis.  相似文献   
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88.

Purpose

Recently, the American Joint Committee on Cancer (AJCC) 7th edition proposed new response criteria for neoadjuvant chemotherapy (NAC) in breast cancer. The purpose of this study was to evaluate the clinical usefulness of AJCC response criteria.

Methods

A total of 398 consecutive stage II or III breast cancer patients who received NAC were enrolled in this study. AJCC response criteria were as follows: (1) complete response (CR)—absence of invasive carcinoma in the breast and node; (2) partial response (PR)—decrease in either or both T or N stage; (3) no response (NR)—no change or increase in either or both T or N stage.

Results

Complete response, PR, and NR by AJCC criteria were 9.8, 59.3, and 30.7 %, respectively. Among the 398 patients, 337 patients were available for both paired pre- and post- breast MRI and chest CT. AJCC response criteria were significantly associated with RECIST criteria (P < 0.001). AJCC response was significantly associated with relapse-free survival (RFS) and overall survival (OS). The 5-year RFS rates were 89.6 % in CR, 74.1 % in PR, and 62.6 % in NR (P = 0.002). The 5-year OS rates were 97.4 % in CR, 88.6 % in PR, and 78.3 % in NR (P = 0.012). When adjusting potential prognostic factors, AJCC response was independently associated with RFS and OS.

Conclusions

AJCC response criteria for NAC in breast cancer have clinical usefulness in evaluating response of NAC, as well as predicting survival. AJCC response criteria can discriminate among patient subgroups with respect to survival.  相似文献   
89.
The majority of clinical trials of neo‐adjuvant therapy for breast cancer have been conducted in resource‐rich countries. We chose Nigeria, a resource‐poor country, as the major site for a phase II feasibility open‐label multicenter clinical trial designed to evaluate the efficacy, safety, and tolerability of neo‐adjuvant capecitabine in locally advanced breast cancer (LABC). Planned treatment consisted of 24 weeks of capecitabine at a dose of 1,000 mg/m2 twice daily (2,000 mg/m2 total per day). The primary endpoints were overall, partial, complete clinical response rate (OCR, PCR, CCR) and complete pathologic response (cPR). A total of 16 patients were recruited from August 2007 to April 2010. The study was terminated early as a result of slow accrual. After the first three cycles of therapy, PCR were seen in five of 16 patients (31%; 95% CI 11–59%). Of the remaining 11 patients, eight had no response (NR) or stable disease (SD), and three had progressive disease (PD). Seven patients proceeded with further therapy of which had SD. OCR at the end of eight cycles was 44% (95% CI 20–70%). Clinical response and radiologic response by ultrasonomammography were highly concordant (spearman correlation 0.70). The most common adverse effect was Grade 1 hand–foot syndrome, which was seen in 75% of patients. Despite several limitations, we successfully carried out this phase II feasibility study of neo‐adjuvant capecitabine for LABC in Nigeria. Capecitabine monotherapy showed good overall response rates with minimal toxicity and further studies are warranted.  相似文献   
90.
Park J‐C, Kim J.C, Kim B‐K, Cho K‐S, Im G‐I, Kim B‐S, Kim C‐S. Dose‐ and time‐dependent effects of recombinant human bone morphogenetic protein‐2 on the osteogenic and adipogenic potentials of alveolar bone‐derived stromal cells. J Periodont Res 2012; 47: 645–654. © 2012 John Wiley & Sons A/S Background and Objective: Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) is a well‐known growth factor that can induce robust bone formation, and recent studies have shown that rhBMP‐2‐induced osteogenesis is closely related to adipogenesis. The aim of the present study was to determine the dose‐ and time‐dependent effects of rhBMP‐2 on the osteogenic and adipogenic differentiation of human alveolar bone‐derived stromal cells (hABCs) in vivo and in vitro. Material and Methods: hABCs were isolated and cultured, and then transplanted using a carrier treated either with or without rhBMP‐2 (100 μg/mL) into an ectopic subcutaneous mouse model. Comprehensive histologic and histometric analyses were performed after an 8‐wk healing period. To further understand the dose‐dependent (0, 10, 50, 200, 500 and 1000 ng/mL) and time‐dependent (0, 3, 5, 7 and 14 d) effects of rhBMP‐2 on osteogenic and adipogenic differentiation, in vitro osteogenic and adipogenic differentiation of hABCs were evaluated, and the expression of related mRNAs, including those for alkaline phosphatase, osteocalcin, bone sialoprotein, peroxisome‐proliferator‐activated receptor gamma‐2 and lipoprotein lipase, were assessed using quantitative RT‐PCR. Results: rhBMP‐2 significantly promoted the osteogenic and adipogenic differentiation of hABCs in vivo, and gradually increased both the osteogenic and adipogenic potential in a dose‐ and time‐dependent manner with minimal deviation in vitro. The expression of osteogenesis‐ and adipogenesis‐associated mRNAs were concomitantly up‐regulated by rhBMP‐2. Conclusion: The findings of the present study showed that rhBMP‐2 significantly enhanced the adipogenic as well as the osteogenic potential of hABCs in dose‐ and time‐dependent manner. The control of adipogenic differentiation of hABCs should be considered when regenerating the alveolar bone using rhBMP‐2.  相似文献   
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