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91.
OBJECTIVE: Involvement of the temporomandibular joint (TMJ) in patients with juvenile idiopathic arthritis (JIA) can cause severe craniofacial growth disturbances if not treated in the initial stage. Magnetic resonance imaging (MRI) is an efficient method for detecting early inflammatory changes of the TMJ. We investigated correlation between findings from the clinical examination with MRI of the TMJ, and describe development of the MR image over time. METHODS: Fifteen children with newly diagnosed JIA (mean age 12.0 yrs) were examined clinically and with MRI enhanced with Gd-DTPA 4 times at 6-8 month intervals. Clinical and MRI findings were scored. MRI variables included T1 weighted images before and after administration of Gd-DTPA with and without fat suppression. RESULTS: A total of 115 joints were examined during the 2 year period: 93% showed enhancement, 71% condylar erosions, 26% pannus, and 23% joint fluid accumulation of the TMJ. In all except one child, one or both TMJ showed enhancement of the synovial membrane during the examination period. Symptoms were rare. All patients showing mild to severe findings by clinical examination also had pathological signs on the enhanced MRI, but not all patients without clinical findings had a normal MRI. CONCLUSION: TMJ involvement in patients with JIA is very common, and MRI findings such as synovial enhancement, pannus, and joint fluid fluctuate over time. The clinical examination may be used as a filter, where children showing no clinical signs could be selected for enhanced MRI.  相似文献   
92.
Epidemiological data demonstrate an association between systemic low-grade inflammation defined as 2- to 3-fold increases in circulating inflammatory mediators and age-related decline in cognitive function. However, it is not known whether small elevations of circulating cytokine levels cause direct effects on human neuropsychological functions. We investigated changes in emotional, cognitive, and inflammatory parameters in an experimental in vivo model of low-grade inflammation. In a double-blind crossover study, 12 healthy young males completed neuropsychological tests before as well as 1.5, 6, and 24 h after an intravenous injection of Escherichia coli endotoxin (0.2 ng/kg) or saline in two experimental sessions. Endotoxin administration had no effect on body temperature, cortisol levels, blood pressure or heart rate, but circulating levels of tumor necrosis factor (TNF) and interleukin (IL)-6 increased 2- and 7-fold, respectively, reaching peak values at 3 h, whereas soluble TNF-receptors and IL-1 receptor antagonist peaked at 4.5 h. The neutrophil count increased and the lymphocyte count declined. In this model, low-dose endotoxemia did not affect cognitive performance significantly but declarative memory performance was inversely correlated with cytokine increases. In conclusion, our findings demonstrate a negative association between circulating IL-6 and memory functions during very low-dose endotoxemia independently of physical stress symptoms, and the hypothalamo-pituitary-adrenal axis.  相似文献   
93.
The physiological and pathophysiological functions of PAI-1 are related to its expression by specific cell types in normal and diseased tissues. We analysed the contribution of DNA methylation to the variation in PAI-1 mRNA levels in five cell lines. We found varying frequencies of methylation of 25 CpGs in the -805/+152 region of the PAI-1 gene in Bowes, MCF-7 and U937 cells, while little or no methylation was detected in Hep2 and HT- 1080 cells. The methylation frequency was inversely correlated with PAI-1 mRNA level within its 20-fold range in Bowes, MCF-7, U937,and Hep2 cells, while the lack of methylation in both Hep2 and HT-1080 cells suggested another mechanism behind the 150-fold higher level in HT- 1080 cells than in Hep2 cells. However, all cell lines exhibited a high frequency of methylation of 10 CpGs in a CpG island at about--1800. Treatment with 5-aza-2'-deoxycytidine led up to circa a 40-fold increase in the PAI-1 mRNA level and a strong decrease in the frequency of methylation in the -805/+152 region in Bowes, MCF-7 and U937. The histone deacetylase inhibitor trichostatin A induced a several fold increase of the PAI-I mRNA level in cells with a high methylation frequency of the -805/+152 region. As compared with matched normal tissue, three samples of oral squamous cell carcinomas displayed decreased frequencies of methylation of the PAI-1 5' flanking region and increased levels of PAI-1 mRNA. These results for the first time implicate DNA methylation and histone acetylation in regulation of the PAI-1 gene, and indicate that without proper CpG islands in 5'-flanking region,trancription may be regulated by methylation of less dense CpGs in the 5'-flanking region rather than methylation of upstream CpG island.  相似文献   
94.
Eukaryotic centromeres are composed of centromere DNA and the multiple proteins directly or indirectly associated with it. One important DNA-binding protein in the centromere is DNA topoisomerase II (topo II). In the genome in general, topo II has two functions, one structural and one enzymatic, the latter catalyzing DNA strand-passage reactions. It has been demonstrated that topo II accumulates at centromeres during the first part of mitosis, and disappears again at anaphase, but it has not been clear whether it serves a structural or an enzymatic function at the centromere. To investigate this issue, we developed the topo II-induced self-primed in situ assay (Topo-SPRINS). In this assay, DNA breaks created by topo II are stabilized with the topo II inhibitor VM-26 in vivo, and used as ‘primers’ for localized DNA synthesis in vitro. The assay revealed that topo II has enzymatic activity at mitotic centromeres and that the activity is relatively constant across centromeres. Furthermore, the activity was observed at a neocentromere, and, in multicentric chromosomes, the activity was restricted to the active centromere. The topo II activity is thus selectively present at functioning centromeres, indicating that it plays a role in mitotic centromere function. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Optimal dose and timing of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy for aggressive non-Hodgkin lymphoma (NHL) is still an unresolved issue. We assessed whether dose intensifications with cyclophosphamide and doxorubicin might improve outcome in younger patients with intermediate-risk aggressive NHL. Previously untreated patients were assigned to receive either 8 courses of standard CHOP (n = 239) or 6 courses of intensified (I)-CHOP (n = 238). Although there was a tendency in favor of I-CHOP for overall survival (OS), disease-free survival (DFS), and event-free survival (EFS), the differences were not significant. However, although these analyses were not planned, when the intermediate-risk group was divided into low-intermediate- and high-intermediate-risk patients according to the International Prognostic Index (IPI), low-intermediate-risk patients had improved 6-year OS (67% vs 52%; P = .05), DFS (58% vs 45%; P = .06), and EFS (41% vs 30%; P = .21) when they were treated with I-CHOP compared with standard CHOP. On the other hand, high-intermediate-risk patients seem to have no benefit from I-CHOP. Although clinically relevant side effects occurred more often in the I-CHOP arm, treatment-related mortality was similar. These data suggest that I-CHOP might be preferable to standard CHOP in younger patients with low-intermediate-risk aggressive NHL.  相似文献   
98.
Background:  To compare the inflammatory changes of antigen-induced temporomandibular joint (TMJ) arthritis in rabbits by different histological methods and to evaluate the immunomodulatory effect of intra-articular corticosteroid injections histologically.
Methods:  35 rabbits (10 weeks old) pre-sensibilized with ovalbumin were divided into three groups: a placebo group of five (saline), an arthritis group of 15 (ovalbumin) and a steroid-treated group of 15 (ovalbumin + corticosteroid). Additionally, a group of seven rabbits receiving no sensibilization with ovalbumin and no intra-articular injections served as controls. Histomorphometry of the inflammatory changes in the subsynovial connective tissue (SSCT) of the TMJ included: (i) semi-quantitative (S-Q) scoring of inflammation and synovial proliferation, (ii) thickness measurements and fractional surface and (iii) stereological quantitative assessment of volume and plasma cells in thick sections of the SSCT by an optical fractionator.
Results:  The histomorphometry showed synovial proliferation in both the arthritis and the steroid groups. The plasma cell count obtained by the optical fractionator was significantly reduced when treating the TMJ with corticosteroids. However, the thickness of the synovial lining and volume of the SSCT as well as S-Q scoring of inflammation showed no difference between the arthritis and the steroid-treated groups. The optical fractionator proved a superior tool compared to S-Q assessments.
Conclusion:  Counting of plasma cells in the SSCT showed that corticosteroids reduced the inflammation, but did not eliminate it. Semiquantitative scoring of synovial proliferation and inflammation demonstrated low sensitivity regarding changes in immunomodulation in antigen-induced arthritis compared to stereological quantitative estimations using an optical fractionator.  相似文献   
99.
PURPOSE: Patients with recurrent cervical carcinoma within a previously irradiated area respond poorly to chemotherapy. We have treated these patients with simultaneous cisplatin and hyperthermia (CDDP + HT) and investigated response, toxicity, palliative effect and survival. MATERIALS AND METHODS: Between 1992 and 2005 47 patients received CDDP + HT. Response was evaluated by gynaecologic examination and CT-scan. The Common Toxicity Criteria (CTC) were used for evaluation of toxicity and palliative effect. The Kaplan-Meier method was used to estimate survival, and Cox regression analysis to evaluate the influence of prognostic factors. RESULTS: The objective response rate was 55%, palliation was achieved in 74% and operability in 19% of patients. Two patients are currently disease free at 9 years and 18 + months following treatment and 2 remained disease free until death by other causes. The median survival was 8 months and was influenced by duration of disease free interval and tumour diameter. Grade 3-4 haematological toxicity was observed in 36% of patients and renal toxicity was maximum grade 2. CONCLUSION: CDDP + HT results in a high response rate and acceptable toxicity in patients with recurrent cervical cancer.  相似文献   
100.
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