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991.
Coronary artery disease is characterized by atherosclerotic plaque formation. Despite impressive advances in intravascular imaging modalities, in vivo molecular plaque characterization remains challenging, and different multimodality imaging systems have been proposed. We validated an engineered bimodal intravascular ultrasound imaging (IVUS) / near-infrared fluorescence (NIRF) imaging catheter in vivo using a balloon injury atherosclerosis rabbit model. Rabbit aortas and right iliac arteries were scanned in vivo after indocyanine green (ICG) injection, and compared to corresponding ex vivo fluorescence and white light images. Areas of ICG accumulation were colocalized with macroscopic atherosclerotic plaque formation. In vivo imaging was performed with the bimodal catheter integrating ICG-induced fluorescence signals into cross-sectional IVUS imaging. In vivo ICG accumulation corresponded to ex vivo fluorescence signal intensity and IVUS identified plaques.OCIS codes: (170.0110) Imaging systems, (110.7170) Ultrasound, (170.6280) Spectroscopy, fluorescence and luminescence, (170.2150) Endoscopic imaging  相似文献   
992.
The association between membranous nephropathy (MN) and immunological disorder-related liver disease has not been extensively investigated, and the specific features of this uncommon association, if any, remain to be determined.We retrospectively identified 10 patients with this association. We aimed to describe the clinical, biological, and pathological characteristics of these patients and their therapeutic management. The possible involvement of the phospholipase A2 receptor (PLA2R) in these apparent secondary forms of MN was assessed by immunohistochemistry with renal and liver biopsy specimens.The mean delay between MN and liver disease diagnoses was 3.9 years and the interval between the diagnosis of the glomerular and liver diseases was <1.5 years in 5 patients. MN was associated with a broad spectrum of liver diseases including primary biliary cirrhosis (PBC), autoimmune hepatitis (AIH), and primary sclerosing cholangitis (PSC). AIH whether isolated (n = 3) or associated with PBC (n = 2) or PSC (n = 2) was the most frequent autoimmune liver disease. Circulating PLA2R antibodies were detected in 4 out of 9 patients but the test was performed under specific immunosuppressive treatment in 3 out of 9 patients. Seven of the 9 patients with available renal tissue specimens displayed enhanced expression of PLA2R in glomeruli whereas PLA2R was not expressed in liver parenchyma from these patients or in normal liver tissue. The study of immunoglobulin (Ig) subclasses of deposits in glomeruli revealed that the most frequent pattern was the coexistence of IgG1 and IgG4 immune deposits with IgG4 predominating.Detection of PLA2R antibodies in glomeruli but not in liver parenchyma is a common finding in patients with MN associated with autoimmune liver disease, suggesting that these autoantibodies are not exclusively detected in idiopathic MN.  相似文献   
993.
994.
Glucosamine products have been used extensively for the management of pain in osteoarthritis. This paper reviews the most recent clinical and experimental studies regarding its efficacy and safety. Although clinical trials include methodologic flaws and publication bias, glucosamine is likely an effective therapy for the symptomatic management of osteoarthritis. In turn, definite proof for chondromodulating effect requires well-conducted clinical trials. In North America, glucosamine is an over-the-counter dietary supplement and preparations made by different manufacturers may vary. There is also a need to standardize this therapy and allow practitioners to give patients suitable advice. An ongoing long-term clinical trial in the US will possibly permit to investigate the clinical relevance of these results and give appropriate recommendations.  相似文献   
995.
Hypertension is associated with increased risk of cardiovascular diseases. Antihypertensive treatment, particularly blockade of the renin-angiotensin system, contributes to prevent atherosclerosis-mediated cardiovascular events. Direct comparison of different antihypertensive treatments on atherosclerosis and particularly plaque stabilization is sparse. ApoE(-/-) mice with vulnerable (2-kidney, 1-clip renovascular hypertension model) or stable (1-kidney, 1-clip renovascular hypertension model) atherosclerotic plaques were used. Mice were treated with aliskiren (renin inhibitor), irbesartan (angiotensin-receptor blocker), atenolol (beta-blocker), or amlodipine (calcium channel blocker). Atherosclerosis characteristics were assessed. Hemodynamic and hormonal parameters were measured. Aliskiren and irbesartan significantly prevented atherosclerosis progression in 2-kidney, 1-clip mice. Indeed, compared with untreated animals, plaques showed thinner fibrous cap (P<0.05); smaller lipid core (P<0.05); decreased media degeneration, layering, and macrophage content (P<0.05); and increased smooth muscle cell content (P<0.05). Interestingly, aliskiren significantly increased the smooth muscle cell compared with irbesartan. Despite similar blood pressure lowering, only partial plaque stabilization was attained by atenolol and amlodipine. Amlodipine increased plaque smooth muscle cell content (P<0.05), whereas atenolol decreased plaque inflammation (P<0.05). This divergent effect was also observed in 1-kidney, 1-clip mice. Normalizing blood pressure by irbesartan increased the plasma renin concentration (5932+/-1512 ng/mL per hour) more than normalizing it by aliskiren (16085+/-5628 ng/mL per hour). Specific renin-angiotensin system blockade prevents atherosclerosis progression. First, evidence is provided that direct renin inhibition mediates atherosclerotic plaque stabilization. In contrast, beta-blocker and calcium channel blocker treatment only partially stabilize plaques differently influencing atherogenesis. Angiotensin II decisively mediates plaque vulnerability. The plasma renin concentration measurement by an indirect method did not confirm the excessive increase of plasma renin concentration reported in the literature during aliskiren compared with irbesartan or amlodipine treatment.  相似文献   
996.
BACKGROUND: Effective treatment of active rheumatoid arthritis (RA) requires early diagnosis and early disease modifying antirheumatic drug (DMARD) treatment to have an impact on long term morbidity and mortality. Clinical criteria would facilitate early referral of the patient with suspected RA to a rheumatologist for definitive diagnosis and initiation of DMARD treatment at that point in the disease most likely to have an impact on the long term outcome. OBJECTIVE: To develop a referral recommendation that may serve as a clinical guide for primary care doctors, enabling them to identify patients with suspected RA during the early inflammatory stages. METHODS: Key points of the referral criteria were formed based on a thorough literature review targeting early RA, early arthritis clinics, DMARD treatment for early RA, prognostic factors of disease progression, early RA clinical trials, and quality of life. Evidence was graded using the methods defined by Shekelle et al. A draft version of the criterion was circulated among the authors for critical evaluation. A consensus integrated these comments. RESULTS: Clinical evidence strongly supports the observations that structural damage occurs early in active RA and that early DMARD treatment improves the long term outcome of the disease. The observations indicate that rapid referral to a rheumatologist is advised when RA is suspected. This may be supported by the presence of any of the following: >or=3 swollen joints, metatarsophalangeal/metacarpophalangeal involvement, and morning stiffness of >or=30 minutes. CONCLUSION: The proposed early referral recommendation is a viable tool for primary care doctors to identify potential patients with active RA early in the disease. Early referral to a rheumatologist for definitive diagnosis and early DMARD treatment should improve the long term outcome of RA.  相似文献   
997.
OBJECTIVE: To obtain an international consensus about the use of anti-tumour necrosis factor alpha (anti-TNF alpha) for treating patients with ankylosing spondylitis (AS). METHODS: These recommendations were developed by a review of published reports in combination with expert opinion, including a Delphi exercise, and a consensus meeting of the ASsessments in AS (ASAS) Working Group. RESULTS: The final consensus comprises the following requirements: (1) For the initiation of anti-TNF alpha therapy: (a) a diagnosis of definitive AS; (b) presence of active disease for at least four weeks as defined by both a sustained Bath AS Disease Activity Index (BASDAI) of at least 4 and an expert opinion based on clinical features, acute phase reactants, and imaging modalities; (c) presence of refractory disease defined by failure of at least two non-steroidal anti-inflammatory drugs during a single three month period, failure of intra-articular steroids if indicated, and failure of sulfasalazine in patients with peripheral arthritis; (d) application and implementation of the usual precautions and contraindications for biological therapy. (2) For the monitoring of anti-TNF alpha therapy: both the BASDAI and the ASAS core set for clinical practice should be followed regularly. (3) For the discontinuation of anti-TNF alpha therapy: in non-responders, consideration should be made after 6-12 weeks' treatment. Response is defined as improvement of (a) at least 50% or 2 units (on a 0-10 scale) of the BASDAI, (b) expert opinion that treatment should be continued. CONCLUSION: This consensus statement on anti-TNF alpha treatment in AS may be used for guidance in clinical decision making and as the basis for the development of guidelines. Evaluation of the healthcare consequences of this consensus is subject to further research by the ASAS group.  相似文献   
998.
OBJECTIVE: A 2-year randomized controlled trial was performed to test the hypothesis that long-term, continuous treatment with nonsteroidal antiinflammatory drugs (NSAIDs), in comparison with NSAID treatment on demand only, influences radiographic progression in patients with ankylosing spondylitis (AS). METHODS: Patients with AS (n = 215), who had previously participated in a 6-week, randomized, double-blind clinical trial that compared celecoxib, ketoprofen, and placebo, were randomly allocated to receive either continuous treatment with NSAIDs or on-demand treatment with NSAIDs for a period of 2 years. All patients began treatment with celecoxib, at a starting dosage of 100 mg twice daily; patients could increase this dosage to 200 mg twice daily or could switch to another NSAID while maintaining the same treatment strategy. Structural changes were assessed by radiographs of the lumbar and cervical spine and scored according to the modified Stoke Ankylosing Spondylitis Spine Score by one observer who was blinded to the treatment strategy and temporal order of the radiographs. Statistical analyses included a between-group comparison of 1) radiographic progression scores (by Mann-Whitney U test), 2) time-averaged values of variables reflecting signs and symptoms of AS (by linear regression analysis), and 3) the frequency of reported site-specific adverse events (by chi-square test or Fisher's exact test, as appropriate). RESULTS: Complete sets of radiographs were available for 76 of the 111 patients in the continuous-treatment group and for 74 of the 104 patients in the on-demand group. The mean +/- SD scores for radiographic progression were 0.4 +/- 1.7 in the continuous-treatment group and 1.5 +/- 2.5 in the on-demand treatment group (P = 0.002). Parameters reflecting signs and symptoms were not statistically significantly different between groups. The between-group difference in radiographic progression did not disappear after adjusting for baseline values of radiographic damage or disease activity variables and for time-averaged values of disease activity variables, nor after input of missing data. Relevant adverse events tended to occur more frequently in the continuous-treatment group than in the on-demand group (for hypertension, 9% versus 3%; for abdominal pain, 11% versus 6%; for dyspepsia, 41% versus 38%), but the differences were not statistically significant. CONCLUSION: A strategy of continuous use of NSAIDs reduces radiographic progression in symptomatic patients with AS, without increasing toxicity substantially.  相似文献   
999.
1000.
The use of T and B lymphocyte markers and of different antisera raised against malignant B cells and fetal thymocytes allowed the classification of 100 patients with acute lymphoblastic leukemia (ALL) into three groups. (I) Patients with non-T non-B ALL whose cells were devoid of conventional B and T markers but characterized by a leukaemia associated antigen (69 cases). (2) Patients with T-derived ALL (28 cases). (3) Patients with ALL of B cell origin (three cases). The search for haematological and clinical correlations showed that those patients with T-derived ALL tended to have a higher leucocyte count (P=0.05) and acid phosphatase positivity of blast cells (P= 0.01), a higher incidence of tumour presentation (P=0.05) and a thymic mass. Survival curves for the two main groups of patients are similar at 36 months but meningeal relapses were more frequent in patients with T-derived ALL (P=0.02).  相似文献   
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