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In rabbits with immune arthritis the numbers of lymphoid aggregates and pyroninophilic and non-pyroninophilic cells per unit area of synovium were calculated from sections taken at various intervals after intra-articular drug injections. A model of immune arthritis based on the results is presented. In the active phase of the arthritis, plasma cells, plasmablasts and lymphoid aggregates proliferate, while the number of lymphocytes decreases. In the inactive phase after treatment, the cell pattern is the reverse. The ratio of pyroninophilic to non-pyroninophilic cells proved to be a good measure of the activity of the arthritis. A favourable therapeutic effect was achieved with triamcinolone hexacetonide and combined steroid-osmic acid, but not with osmic acid alone.  相似文献   
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AIMS: Peroxisome proliferator-activated receptor gamma (PPARgamma) activators have recently been identified as regulators of cellular proliferation, inflammatory responses and lipid and glucose metabolism. These agents prevent coronary arteriosclerosis and improve left ventricular remodelling and function in heart failure after myocardial infarction. Improvement in myocardial metabolic state may be one of the mechanisms behind these findings. The aim of this study was to investigate the effects of rosiglitazone on myocardial glucose uptake in patients with Type 2 diabetes. Placebo and metformin were used as control treatments. METHODS: Forty-four patients were randomized to treatment with rosiglitazone (4 mg b.i.d.), metformin (1 g b.i.d.) or placebo in a 26-week double-blinded trial. Myocardial glucose uptake was measured using [(18)F]-2-fluoro-2-deoxy-D-glucose ([(18)F]FDG) and positron emission tomography (PET) during euglycaemic hyperinsulinaemia before and after the treatment. RESULTS: Rosiglitazone increased insulin-stimulated myocardial glucose uptake by 38% (from 38.7 +/- 3.4 to 53.3 +/- 3.6 micromol 100 g(-1) min(-1), P = 0.004) and whole body glucose uptake by 36% (P = 0.01), while metformin treatment had no significant effect on myocardial (40.5 +/- 3.5 vs. 36.6 +/- 5.2, NS) or whole body glucose uptake. Myocardial work as determined by the rate-pressure-product was similar between the groups. Neither treatment had any significant effect on fasting serum free fatty acids (FFA) but the FFA levels during hyperinsulinaemia were more suppressed in the rosiglitazone group (-47%, P = 0.02). Myocardial glucose uptake correlated inversely to FFA concentrations both before (r =-0.54, P = 0.002) and after (r = -0.43, P = 0.01) the treatment period in the pooled data. Furthermore, the increase in myocardial glucose uptake correlated inversely with interleukin-6 (IL-6) concentrations (r = -0.58, P = 0.03). CONCLUSIONS: In addition to the improvement in whole body insulin sensitivity, rosiglitazone treatment enhances insulin stimulated myocardial glucose uptake in patients with Type 2 diabetes, most probably due to its suppression of the serum FFAs.  相似文献   
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Background

Individual depressive symptoms may contribute to the risk of chronic depression. This study aimed to explore which symptoms predict chronic dysphoria, a hallmark of depression.

Methods

1057 participants from the population-based Young Finns study were examined for four times during a 16-year period. Those with a modified Beck’s Depression Inventory score in the upper third at all four screenings were considered to have chronic dysphoria (n=135). Participants with only one high depression score formed the reference group of transient dysphoria (n=179). Individual items of the Inventory were analyzed in terms of their association with dysphoria status and chronicity, controlling for potential confounding factors, such as personality assessed using the Temperament and Character Inventory.

Results

Body-image dissatisfaction was strongly associated with chronically elevated dysphoria (Bonferroni-corrected p=0.006). The degree of body-image dissatisfaction was associated with the probability for chronic dysphoria in a dose–response manner, with the estimated probability ranging from 0.01 to 0.60 as a function of item response. The association remained after adjustments for a wide range of personality characteristics.

Limitations

The study relied on self-reports of mood and personality, and lacked information on external opinion on participants appearances. The requirement of full time-series data may have resulted in attrition-related bias.

Conclusions

Body-image dissatisfaction was a strong predictor of chronic depression characterized by dysphoria. This finding suggests that dysfunctional attitude towards oneself might represent a potentially important target for cognitive therapies and preventive interventions.  相似文献   
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Ameloblastoma is a benign but locally infiltrative odontogenic neoplasm. Although ameloblastomas rarely metastasise, recurrences together with radical surgery often result in facial deformity and significant morbidity. Development of non‐invasive therapies has been precluded by a lack of understanding of the molecular background of ameloblastoma pathogenesis. When addressing the role of ERBB receptors as potential new targets for ameloblastoma, we discovered significant EGFR over‐expression in clinical samples using real‐time RT–PCR, but observed variable sensitivity of novel primary ameloblastoma cells to EGFR‐targeted drugs in vitro. In the quest for mutations downstream of EGFR that could explain this apparent discrepancy, Sanger sequencing revealed an oncogenic BRAF V600E mutation in the cell line resistant to EGFR inhibition. Further analysis of the clinical samples by Sanger sequencing and BRAF V600E‐specific immunohistochemistry demonstrated a high frequency of BRAF V600E mutations (15 of 24 samples, 63%). These data provide novel insight into the poorly understood molecular pathogenesis of ameloblastoma and offer a rationale to test drugs targeting EGFR or mutant BRAF as novel therapies for ameloblastoma. Published by John Wiley & Sons, Ltd. www.pathsoc.org.uk  相似文献   
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