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91.
IntroductionThe objective of this study was to assess the effects of an educational program on the course of rheumatoid arthritis (RA) after 3 years.MethodsFrom December 2002 to December 2003, 39 RA patients participated in a 3-day education program delivered to groups of four or five patients. Effects of the program were evaluated after 3 years in 33 patients, comparatively to baseline, based on the following variables: knowledge of RA (self-questionnaire), disease activity (DAS 28), functional impairment (health assessment questionnaire [HAQ]) and quality of life (arthritis impact measurement scale 2 [AIMS2], short-form). We also compared patient knowledge in the educational program participants and in 38 controls with RA. Direct questions were used to evaluate the program after 3 years.ResultsPatient knowledge 3 years after the education program was significantly improved compared to baseline (P < 0.0001) and was significantly better than in the controls (P < 0.0001). Disease activity was significantly lower in the education group after 3 years than at baseline (DAS28, 3.1 vs. 3.8, P < 0.005). Neither the HAQ nor the AIMS2 scores changed significantly after 3 years compared to baseline. The replies to the direct questions indicated a very high level of overall satisfaction with the educational program.ConclusionAn educational program tailored to patient needs can produce lasting improvements in knowledge of the disease and may help to control the activity of RA. These results warrant the development of education programs for patients with chronic inflammatory joint disease.  相似文献   
92.
We describe affinity sensors for monitoring various metabolites in blood plasma by optical means. The principle of detection is similar to that used in radioimmunoassays and is based on the competitive binding of a particular metabolite and a fluorescein-labeled analogue with receptor sites specific for the metabolite and the labeled ligand. This concept has been directed toward the development of an affinity sensor for glucose. Concanavalin A, a protein with specific binding character for glucose, was immobilized on the inside surface of a hollow dialysis fiber. Fluorescein-labeled dextran was selected as the competitive labeled ligand. The molecular weight cutoff of the dialysis fiber is low enough to completely retain the 70,000 MW dextran within the fiber lumen while glucose can freely pass through the dialysis membrane. The sensor is completed by inserting a single optical fiber in the lumen of the dialysis fiber, thus allowing measurement of the unbound FITC-dextran. Preliminary tests of the sensor indicated the feasibility of the approach. Sensitivity to glucose in the physiologic range was obtained, but further work will be required to optimize the sensitivity and response time of the sensor.  相似文献   
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Background Context

Predictors of outcome after surgery for degenerative cervical myelopathy (DCM) have been determined previously through hypothesis-driven multivariate statistical models that rely on a priori knowledge of potential confounders, exclude potentially important variables because of restrictions in model building, cannot include highly collinear variables in the same model, and ignore intrinsic correlations among variables.

Purpose

The present study aimed to apply a data-driven approach to identify patient phenotypes that may predict outcomes after surgery for mild DCM.

Study Design

This is a principal component analysis of data from two related prospective, multicenter cohort studies.

Patient Sample

The study included patients with mild DCM, defined by a modified Japanese Orthopaedic Association score of 15–17, undergoing surgical decompression as part of the AOSpine CSM-NA or CSM-I trials.

Outcome Measures

Patient outcomes were evaluated preoperatively at baseline and at 6 months, 1 year, and 2 years after surgery. Quality of life (QOL) was evaluated by the Neck Disability Index (NDI) and Short Form-36 version 2 (SF-36v2). These are both patient self-reported measures that evaluate health-related QOL, with NDI being specific to neck conditions and SF-36v2 being a generic instrument.

Materials and Methods

The analysis included 154 patients. A heterogeneous correlation matrix was created using a combination of Pearson, polyserial, and polychoric regressions among 67 variables, which then underwent eigen decomposition. Scores of significant principal components (PCs) (with eigenvalues>1) were included in multivariate logistic regression analyses for three dichotomous outcomes of interest: achievement of the minimum clinically important difference [MCID] in (1) NDI (≤?7.5), (2) SF-36v2 Physical Component Summary (PCS) score (≥5), and (3) SF-36v2 Mental Component Summary (MCS) score (≥5).

Results

Twenty-four significant PCs accounting for 75% of the variance in the data were identified. Two PCs were associated with achievement of the MCID in NDI. The first (PC 1) was dominated by variables related to surgical approach and number of operated levels; the second (PC 21) consisted of variables related to patient demographics, severity and etiology of DCM, comorbid status, and surgical approach. Both PC 1 and PC 21 also correlated with SF-36v2 PCS score, in addition to PC 4, which described patients' physical profile, including gender, height, and weight, as well as comorbid renal disease; PC 6, which received large loadings from variables related to cardiac disease, impaired mobility, and length of surgery and recovery; and PC 9, which harbored large contributions from features of upper limb dysfunction, cardiorespiratory disease, surgical approach, and region. In addition to PC 21, a component profiling patients' socioeconomic status and support systems and degree of physical disability (PC 24) was associated with achievement of the MCID in SF-36 MCS score.

Conclusions

Through a data-driven approach, we identified several phenotypes associated with disability and physical and mental health-related QOL. Such data reduction methods may separate patient-, disease-, and treatment-related variables more accurately into clinically meaningful phenotypes that may inform patient care and recruitment into clinical trials.  相似文献   
94.
BACKGROUND: Acetaminophen was falsely detected in the plasma of a severely jaundiced patient, and a methodologic interference from bilirubin was suspected. METHODS: Acetaminophen was measured by an enzymatic method (GDS Diagnostics). The putative bilirubin interference was investigated in 12 hyperbilirubinemic specimens and in bilirubin linearity calibrators. The analytical method was modified to correct for background absorbance at a second wavelength. Hyperbilirubinemic specimens were fortified with acetaminophen to assess the effect of the interference on acetaminophen measurements. RESULTS: Acetaminophen was detected in 12 specimens from hyperbilirubinemic patients without a history of recent acetaminophen exposure. Dilution of hyperbilirubinemic specimens produced a nonproportional decrease in apparent acetaminophen concentrations, and no acetaminophen was detected when bilirubin was <50 mg/L. Background correction at a second wavelength failed to compensate for the interference. Although erroneous acetaminophen concentrations were detected in all specimens with high bilirubin, acetaminophen measurements in fortified specimens were accurate. CONCLUSION: The data are consistent with bilirubin interference in the enzymatic and/or chromogenic reactions involved in the acetaminophen method.  相似文献   
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Intracellular sources of peroxynitrite formation and potential targets for this powerful oxidant and nitrating agent have not been identified after acetaminophen (AAP) overdose. Therefore, we tested the hypothesis that peroxynitrite generated in mitochondria may be responsible for mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) damage. C3Heb/FeJ mice were treated with 300 mg/kg AAP and monitored for up to 12 h. Loss of mtDNA (assayed by slot blot hybridization) and substantial nDNA fragmentation (evaluated by anti-histone enzyme-linked immunosorbent assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, and agarose gel electrophoresis) were observed as early as 3 h after AAP overdose. Analysis of nitrotyrosine protein adducts in subcellular fractions established that peroxynitrite was generated predominantly in mitochondria beginning at 1 h after AAP injection. Delayed treatment with a bolus dose of glutathione (GSH) accelerated the recovery of mitochondrial glutathione, which then effectively scavenged peroxynitrite. However, mtDNA loss was only partially prevented. Despite the absence of nitrotyrosine adducts in the nucleus after AAP overdose, nDNA damage was almost completely eliminated with GSH administration. A direct comparison of nDNA damage after AAP overdose with nDNA fragmentation during tumor necrosis factor receptor-mediated apoptosis showed similar DNA ladders on agarose gels but quantitatively different results in three other assays. We conclude that peroxynitrite may be partially responsible for mtDNA loss but is not directly involved in nDNA damage. In contrast, nDNA fragmentation after AAP overdose is not caused by caspase-activated DNase but most likely by other intracellular DNase(s), whose activation is dependent on the mitochondrial oxidant stress and peroxynitrite formation.  相似文献   
99.
The Middle East (ME) is an ethnically and economically diverse region. A systematic review of all stroke studies conducted in the ME was carried out, with the aim of determining the prevalence of classic vascular risk factors (CRFs) across this region. Additionally, the prevalence of CRFs in the ME was compared to that of a US cohort. Prospective and retrospective ME stroke studies published from 1994 to 2014 were searched for that specifically reported on the prevalence of CRFs. The Z test for proportions was used to determine the significance of differences in CRF rates between the ME and non‐ME studies. A total of 21 724 stroke patients from 13 nations in the ME were included. The prevalence rates for CRFs in the ME stroke population were hypertension, 62.1%; diabetes, 33.1%; dyslipidaemia, 36.8%; ischaemic heart disease, 24.6%; smoking, 19.3%; and atrial fibrillation, 13.6%. Compared to the US cohort, ME patients had a lower prevalence of all CRFs except diabetes (< 0.0001) and smoking (P = 0.05). Compared with stroke patients in the USA, those in the ME have a significantly higher prevalence of diabetes and smoking. Education and lifestyle modification is perhaps the most effective strategy in reducing the risk of stroke in this population.  相似文献   
100.
Cerebrovascular complications of endocarditis occur in 25–70% of patients with infective endocarditis. The cornerstone of treatment is early initiation of antibiotic treatment, which significantly reduces the risk of embolization after 1 week of treatment. In general, thrombolysis and anticoagulation of these patients should be avoided, while antiplatelet therapy may be considered in those with other indications. Endovascular treatment of acute septic emboli is uncertain, but a few case reports have demonstrated benefit. Other complications of infective endocarditis include intracerebral hemorrhage, which may be predicted by the presence of two or more cerebral microbleeds on gradient echo sequences. Intracranial mycotic aneurysms can often be managed with serial imaging and coiled if there is evidence of failure to reduce in size, or enlargement.  相似文献   
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