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991.

Objective

For patients with rheumatoid arthritis (RA) in remission who are receiving disease‐modifying antirheumatic drugs (DMARDs), radiographic progression correlates with imaging‐detected synovitis as measured by power Doppler activity. In contrast, patients with disease in remission who are receiving the combination of tumor necrosis factor (TNF) blockade with methotrexate (MTX) (combination treatment) have reduced radiographic damage for the equivalent clinical state. We undertook this study to determine whether the difference in radiographic outcome is a result of more complete suppression of imaging‐detected synovitis.

Methods

One hundred patients with RA in remission (Disease Activity Score in 28 joints [DAS28] <2.6) for at least 6 months while receiving either combination treatment (n = 50) or DMARDs (n = 50) were matched for clinical variables. Ultrasound of metacarpophalangeal joints 1–5 and the wrist joints was performed. Remission according to imaging results was defined as a score of 0 for both grey scale synovitis and power Doppler activity.

Results

In patients receiving combination treatment or DMARDs (median DAS28 1.65 versus 1.78, median disease duration 120 months versus 90 months, and median duration of remission 13 months versus 18 months), the proportion with remission according to imaging results was not significantly different (10% versus 16%, respectively). The combination treatment group had more grey scale synovitis (P < 0.001) but similar power Doppler activity (48% versus 60%, respectively; P = 0.229) in any joint as compared with the DMARD group. Results were not affected by stratification for duration of disease or remission.

Conclusion

In RA patients with disease in remission, imaging‐detected synovitis persists, with power Doppler activity seen in ≥48% of the patients regardless of therapy. These results suggest that superior radiographic outcomes in patients treated with the combination of TNF blockade and MTX may not be due to complete suppression of imaging‐detected synovitis.
  相似文献   
992.
993.
The long-term metabolic and functional effects of a dietary deprivation of long-chain polyunsaturated ω3 fatty acids were recently investigated in second-generation ω3-depleted rats. This study represents the first attempt to explore the direct, but not immediate, effects of ω3 fatty acids on insulin-producing cells. For this purpose, BRIN-BD11 cells were cultured for 24 h in the absence or presence of both C20:5ω3 and C22:6ω3 (50 μM each) and, thereafter, examined for their phospholipid and triglyceride fatty acid pattern, and their metabolic, ionic, and secretory responses to d-glucose and/or non-nutrient insulinotropic agents. The prior culture in the presence of the two ω3 fatty acids provoked an enrichment of cell lipids in such ω3 fatty acids, changes in the phospholipid fatty acid pattern of long-chain polyunsaturated ω6 fatty acids as well as saturated and monodesaturated fatty acids, and cell steatosis. It minimized the relative increase in d-[5-3H]glucose utilization and d-[U-14C]glucose oxidation otherwise resulting from an increase in the concentration of the hexose from 1.1 to 11.1 mM. It also minimized the changes in 86Rb+ net uptake otherwise provoked by rises in d-glucose concentration and decreased the absolute values for insulin output. It is concluded that the major changes in metabolic, cationic, and secretory behavior of the ω3-enriched BRIN-BD11 cells are paradoxically similar to those encountered in pancreatic islets from ω3-depleted rats and, in both cases, possibly attributable to a phenomenon of lipotoxicity.  相似文献   
994.
Oxidized low-density lipoproteins (LDLs) accumulate in the vascular wall and promote local inflammation, which contributes to the progression of the atheromatous plaque. The key role of myeloperoxidase (MPO) in this process is related to its ability to modify APO B-100 in the intima and at the surface of endothelial cells. A series of 3-(aminoalkyl)-5-fluoroindole analogues was designed and synthesized by exploiting the structure-based docking of 5-fluorotryptamine, a known MPO inhibitor. In vitro assays were used to study the effects of these compounds on the inhibition of MPO-mediated taurine chlorination and oxidation of LDLs. The kinetics of the interaction between the MPO redox intermediates, Compounds I and II, and these inhibitors was also investigated. The most potent molecules possessed a 4- or 5-carbon aminoalkyl side chain and no substituent on the amino group. The mode of binding of these analogues and the mechanism of inhibition is discussed with respect to the structure of MPO and its halogenation and peroxidase cycles.  相似文献   
995.
We studied the aerobic bacterial isolates from bile and their susceptibilty pattern in patients with biliary tract disease. Samples of bile collected during endoscopic retrograde cholangio pancreatography (ERCP) and surgery, were inoculated on standard media. Bacterial identification and susceptibility were done by standard techniques. A total of 209 samples were cultured, out of which 128 samples showed growth. Total number of isolates obtained was 221. Poly-microbial infection was detected in 67 patients. Predominant aerobic bacterial isolates obtained were Escherichia coli 30% (67), Klebsiella species 23.98% (53), Enterococcus species 12.21% (27). Multi-drug resistance was noted in 57%. Higher resistance rate was noted among Gram negative bacilli for ampicillin (92.4%), cephalexin (82.46%), ciprofloxacin (68.42%), piperacillin (64.33%). Sensitivity to meropenem was 90.64% and amikacin was 76.61%. Gram positive bacteria showed high resistance to gentamicin (39.53%). Sensitivity to ampicillin was 86.05% and penicillin was 81.4%. Vancomycin and teicoplanin showed 100% sensitivity. From our study we conclude that E. coli, Klebsiella species and Enterococcus species are common pathogens infecting biliary tract. Poly-microbial infection and multi-drug resistance warrants culture and sensitivity to guide antimicrobial therapy. We recommend combination of amikacin and ampicillin for empirical therapy at our institution.  相似文献   
996.
Alzheimer's disease (AD) reduces associative effects on false recognition in the Deese-Roediger-McDermott task, either due to impaired memory for gist or impaired use of gist in memory decisions. Gist processes were manipulated by blocking or mixing studied words according to their associations and by varying the associative strength between studied and nonstudied words at test. Both associative blocking and associative strength had smaller effects on false recognition in AD patients than in control participants, consistent with gist memory impairments. However, unlike the case with control participants, blocking influenced true and false recognition equally in AD patients, demonstrating an overdependence on gist when making memory decisions. AD also impaired item-specific recollections, relative to control participants, as true recognition of studied words was reduced even when the two groups were equated on gist-based false recognition. We propose that the overdependence on degraded gist memory in AD is caused by even larger impairments in item-specific recollections.  相似文献   
997.
Gangliosides are ubiquitous, membrane-associated, glycosphingolipids, the composition and production of which is altered in many tumour cells. They have been shown to inhibit the in vitro generation and differentiation of dendritic cells (DCs) from progenitors, but their effect on human tissue-residing DCs is yet to be investigated. In the present study, we analysed the effect of GM3 and GD3 gangliosides purified from human melanoma tumours on the phenotypic and functional maturation of human epidermal Langerhans cells (LCs), the first immune barrier against the tumour cells. We showed that both gangliosides impaired spontaneous LC maturation induced by a short in vitro culture, as assessed by significant down-regulation of co-stimulation (CD40, CD54, CD80, CD86) and maturation markers (CD83, CCR7), which correlated to an impaired ability of the cells to mount allogeneic T cell proliferation. Furthermore, the ganglioside-treated cells displayed less ability to migrate towards CCL19/macrophage inflammatory protein 3 beta, the chemokine that specifically binds CCR7 and mediates LC migration to lymph nodes. Lastly, we showed that both GM3 and GD3 gangliosides enhance LC spontaneous apoptosis. Globally, these in vitro results might explain, at least in part, the altered number and distribution of LCs in melanoma-bearing patients. They underscore a new mechanism for gangliosides to impede the host immune response by inducing LC dysfunction in the tumour microenvironment.  相似文献   
998.
BACKGROUND: Several large, randomized, double-blind, placebo-controlled trials have found topiramate (TPM) to be effective and generally well tolerated as a preventive therapy for migraine. OBJECTIVE: This paper evaluates efficacy and safety data from a pilot study of TPM 200 mg/d as preventive therapy in adult subjects with a history of migraine with or without aura. METHODS: The pilot study had a randomized, double-blind, placebo-controlled design. Subjects were randomized in a 2:1 ratio to receive TPM 200 mg/d or placebo. The double-blind treatment phase consisted of an 8-week titration period (25 mg/d for the first week, followed by weekly increases of 25 mg) and a 12-week maintenance period. The primary efficacy measure was the change in mean monthly migraine frequency. Additional measures were the median percent reduction in monthly migraine frequency and the proportion of responders (those with > or =50%, > or =75%, or 100% reduction in monthly migraine frequency). RESULTS: The intent-to-treat (ITT) population included 211 subjects (138 TPM, 73 placebo; mean [SD] mean weight, 76.7 [18.7] kg). Of 45 subjects who discontinued the study in the TPM group, 21 discontinued during the titration period, compared with 3 of 13 subjects who discontinued in the placebo group. When the efficacy data were assessed using the per-protocol, analysis-of-covariance model, TPM 200 mg/d was not associated with a significant reduction in mean monthly migraine frequency compared with placebo. A post hoc analysis using a Poisson regression model in the ITT population suggested that TPM significantly reduced mean monthly migraine frequency compared with placebo (P=0.04). A significantly larger proportion of TPM-treated subjects had a > or =75% reduction in monthly migraine frequency compared with placebo (P=0.03). At least 1 adverse event was reported by 90.0% and 69.9% of the TPM and placebo groups, respectively. Treatment-emergent adverse events (AEs) occurring in > or =10% of subjects in the TPM group were paresthesia (45%), dizziness (16%), fatigue (16%), nausea (14%), and weight loss (14%). Most treatment-emergent AEs were rated mild or moderate in severity. Of 3 serious AEs (depression, abdominal pain, leg pain) occurring during the trial, none were considered related to either TPM or placebo. CONCLUSION: In this pilot study, mean monthly migraine frequency did not differ significantly between TPM and placebo.  相似文献   
999.
1000.
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