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Optical Coherence Tomography (OCT) is an evolving imaging technology allowing non‐destructive imaging of cartilage tissue at near‐histological resolution. This study investigated the diagnostic value of real time 3‐D OCT in comparison to conventional 2‐D OCT in the comprehensive grading of human cartilage degeneration. Fifty‐three human osteochondral samples were obtained from eight total knee arthroplasties. OCT imaging was performed by either obtaining a single two‐dimensional cross‐sectional image (2‐D OCT) or by collecting 100 consecutive parallel 2‐D OCT images to generate a volumetric data set of 8 × 8 mm (3‐D OCT). OCT images were assessed qualitatively according to a modified version of the DJD classification and quantitatively by algorithm‐based evaluation of surface irregularity, tissue homogeneity, and signal attenuation. Samples were graded according to the Outerbridge classification and statistically analyzed by one‐way ANOVA, Kruskal Wallis and Tukey's or Dunn's post‐hoc tests. Overall, the generation of 3‐D volumetric datasets and their multiple reconstructions such as rendering, surface topography, parametric, and cross‐sectional views proved to be of potential diagnostic value. With increasing distance to the mid‐sagittal plane and increasing degeneration, score deviations increased, too. In conclusion, 3‐D imaging of cartilage with image analysis algorithms adds considerable potential diagnostic value to conventional OCT diagnostics. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:651–659, 2015.  相似文献   
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This meta‐analysis aimed to compare outcomes following bile duct reconstruction in patients with primary sclerosing cholangitis (PSC) undergoing liver transplantation depending on whether duct‐to‐duct or Roux‐en‐Y anastomosis was utilized. An electronic search was performed of the MEDLINE, EMBASE, PubMed databases using both subject headings (MeSH) and truncated word searches. Pooled risk ratios and mean difference were calculated using the fixed‐effects and random‐effects models for meta‐analysis. Ten studies including 910 patients met the inclusion criteria. There was no difference in the overall incidence of biliary strictures between the two groups [odds ratio (OR) 1.06 (0.68, 1.66); (P = 0.80)]. The anastomotic stricture rate was similar, [OR 1.18 (0.56, 2.50); (P = 0.67)]. Ascending cholangitis was higher in the Roux–en‐Y group [OR 2.91 (1.17, 7.23); (P = 0.02)]. Anastomotic bile leak rates, graft survival, PSC recurrence and number of patients diagnosed with cholangiocarcinoma following transplantation were comparable between both groups. Duct‐to‐duct and Roux‐en‐Y reconstruction had comparable outcomes. Both techniques are associated with similar incidence of biliary stricture. The bilioenteric reconstruction was associated with a higher risk of cholangitis. The incidence of de novo cholangiocarcinoma was similar in both groups. Duct‐to‐duct reconstruction should be considered when feasible in patients with PSC.  相似文献   
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ObjectivesThe authors report the procedural and 30-day results of the PASCAL Transcatheter Valve Repair System (Edwards Lifesciences, Irvine, California) in patients with mitral regurgitation (MR) enrolled in the multicenter, prospective, single-arm CLASP study.BackgroundSevere MR may lead to symptoms, impaired quality of life, and reduced functional capacity when untreated.MethodsEligible patients had grade 3+ or 4+ MR despite optimal medical therapy and were deemed appropriate for the study by the local heart team. All outcomes were assessed through 30 days post-procedure. Major adverse events (MAEs) were adjudicated by an independent clinical events committee, and echocardiographic images were assessed by a core laboratory. The primary safety endpoint was the rate of MAEs at 30 days.ResultsBetween June 2017 and September 2018, 62 patients with grade 3+ or 4+ MR were enrolled. The mean age was 76.5 years, and 51.6% of patients were in New York Heart Association functional class III or IV, with 56% functional, 36% degenerative, and 8% mixed MR etiology. At 30 days, the MAE rate was 6.5%, with an all-cause mortality rate of 1.6% and no occurrence of stroke; 98% had MR grade ≤2+, with 86% with MR grade ≤1+ (p < 0.0001); and 85% were in New York Heart Association functional class I or II (p < 0.0001). Six-minute walk distance improved by 36 m (p = 0.0018), and Kansas City Cardiomyopathy Questionnaire and EQ-5D scores improved by 17 (p < 0.0001) and 10 (p = 0.0004) points, respectively.ConclusionsThe PASCAL repair system showed feasibility and acceptable safety in the treatment of patients with grade 3+ or 4+ MR. MR severity, irrespective of etiology, was significantly reduced and accompanied by clinically and statistically significant improvements in functional status, exercise capacity, and quality of life. (The CLASP Study Edwards PASCAL Transcatheter Mitral Valve Repair System Study; NCT03170349)  相似文献   
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Surfactant protein-D (SP-D), a member of the "collectin" family, has been shown to play a role in innate immunity through modulation of inflammation and clearance of organisms. The role of SP-D in host defense against Pneumocystis carinii pneumonia was assessed using SP-D knockout (KO) mice. When inoculated with P. carinii, both wild-type (wt) and SP-D KO mice required CD4 cell depletion to develop infection. In CD4 cell-depleted models, 2 weeks after infection with P. carinii, SP-D KO mice developed increased intensity of infection, compared with wt mice, despite higher lung-inflammation scores and increased amounts of alveolar inflammatory cells. The increased inflammation seen in SP-D KO mice was accompanied by increases in lung weight, expression of inducible nitric oxide (NO) synthase, total NO levels, and 3-nitrotyrosine levels in lung tissue. These results indicate that SP-D plays a role in host defense against P. carinii in vivo by modulating clearance of organisms, lung inflammation, and metabolism of NO.  相似文献   
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From May 2004 to October 2006, a prospective study was carried out in Dakar, Senegal, to update information about the antimicrobial susceptibility of Shigella spp. isolated from stool specimens. Among the 165 non-duplicate strains collected, 81 (49%) were identified as Shigella flexneri, 75 (45%) as Shigella sonnei, 5 (3%) as Shigella boydii, and 4 (2%) as Shigella dysenteriae. Disk diffusion testing revealed that the majority of isolates were resistant to sulphonamides, trimethoprim-sulfamethoxazole, streptomycin, and tetracycline (respective overall resistance rates: 90, 90, 96, and 94%). More than half of the S. flexneri isolates were resistant to amoxicillin, amoxicillin-clavulanic acid, and chloramphenicol (respective resistance rates: 59, 58, and 52%), and almost all of the S. sonnei isolates were susceptible to these antimicrobials (respective resistance rates: 4, 1, and 4%). Only one isolate (belonging to the species S. sonnei) was resistant to nalidixic acid and displayed reduced susceptibility to ciprofloxacin.  相似文献   
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