Association between intraplaque neovascularization assessed by contrast-enhanced ultrasound and the risk of stroke.

AIM: To determine the cut-off value of the area ratio under the curve (ARUC) for predicting symptoms of stroke. MATERIALS AND METHODS: Contrast-enhanced ultrasound was used to analyse intraplaque neovascularization (IPN). The correlations between the ARUC and risk factors of stroke were examined. A receiver operating characteristic curve was used to determine the cut-off value of the ARUC. RESULTS: Using a quantitative analysis method for IPN, the ARUC was significantly higher in the symptomatic group than in the asymptomatic group (p=0.017). The ARUC was positively associated with the homocysteine level (r=0.429, p=0.002) and high-sensitivity C-reactive protein level (r=0.424, p=0.003). Regression analysis showed that the ARUC was a risk factor for symptoms of stroke. The receiver operating characteristic curve showed that the cut-off value for symptoms was 0.24; the sensitivity was 77%, and the specificity was 70%; the positive predictive value was 68%, and the negative predictive value was 78%. CONCLUSION: IPN was a risk factor for the occurrence of the clinical symptoms of stroke. Patients with an ARUC of >0.24 had a higher risk of stroke.

[Effects of reconstruction with unicondylar osteoarticular allografts with or without prosthesis for bone tumors around knee joint].

Objective: To investigate the survival rate, function outcomes, and complications after using unicondylar osteoarticular allografts with or without prosthesis to reconstruct the knee joint for tumors located in distal femoral or proximal tibial uni-condyle. Methods: Twenty-two patients who underwent unicondylar osteoarticular allografts with or without prosthesis composite reconstructions from January 2007 to December 2015 in Department of Orthopaedic Surgery of Xi Jing Hospital, the Fourth Military Medical University were retrospectively reviewed. There were 14 males and 8 females and the mean age was 35 years(8-65 years). There were 12 malignent tumors and 10 aggressive benign tumors. The tumors were located in distal femur in 14 cases and proximal tibia in 8 cases. After tumor excision, the distal femur was reconstructed with unicondylar osteoallograft-prosthesis composite, and proximal tibial plate was reconstructed with unicondylar osteoarticular allograft with the help of computer-assisted navigation system. Function and radiograph were documented according to the Musculoskeletal Tumor Society (MSTS) functional scoring system and the International Society of Limb Salvage (ISOLS) radiographic scoring system. The median follow-up time was 60 months (5-116 months). Results: At the latest follow-up, 2 patients had amputation owing to local recurrence in 12 malignant tumors. Three patients had pulmonary metastasis and 1 patient died another 2 alive with disease. Kaplan-Meier analysis indicated that the disease-free survival rate was 73%. There was no recurrence and metastasis in 10 patients with giant cell tumor. The average MSTS score was 26 points and the radiographic score was 78%-94%(average 90%). The complications included superficial infection in 1 patient and screw broken in 1 patient. There was no broken or collapse allograft in all composite reconstruction patients but 6 cases in allograft reconstruction. Conclusions: Unicondylar osteoarticular allografts or prosthesis composite was feasible reconstruction for tumors in distal femoral uni-condyle. It could provide good functional outcomes and also prevent joint degeneration. Similarly, allograft reconstruction was also a reliable technique for proximal tibial defect.

Population structure analysis and association mapping of blast resistance in indica rice (Oryza sativa L.) landraces.

Rice blast caused by Magnaporthe oryzae is one of the most devastating rice diseases worldwide. To understand the genetic diversity of indica landrace accessions and identify simple sequence repeat (SSR) markers that are associated with blast resistance, a population of 276 indica landraces from across the world was constructed. This population was then used to evaluate the blast-resistance phenotype through artificial inoculation under controlled conditions in 2012 and 2013. The genetic diversity and association of the population with resistance were analyzed by examining the phenotype for 160 SSR markers distributed on 12 rice chromosomes. The 276 accessions were classified into seven groups using model- and distance-based cluster analyses. Associations between SSR markers and blast resistance showed that 26 SSR markers were significantly associated with blast resistance in 2012 and 2013 (P < 0.01) and that the phenotypic variation ranged from 2.68 to 13.11%. Nineteen of the markers associated with blast resistance were located in regions where genes or quantitative trait loci (QTLs) have been previously reported, and seven were newly identified in this study. These results indicate that marker-trait association has potential advantages over classical linkage analysis and QTL mapping, and that these markers could be used for marker-assisted selection in rice blast-resistance-breeding programs.

Identification of quantitative trait loci conferring blast resistance in Bodao, a japonica rice landrace.

Bodao, a japonica landrace from the Taihu Lake region of China, is highly resistant to most Chinese isolates of Magnaporthe oryzea, a form of rice blast. To effectively dissect the influence of genetics on this blast resistance, a population of 155 recombinant inbred lines (F2:8) derived from a cross of Bodao x Suyunuo was inoculated with 12 blast isolates. Using a quantitative trait locus (QTL) mapping approach, 13 QTL on chromosomes 1, 2, 9, 11, and 12 were detected from Bodao. Five QTL, including qtl11-1-1, qtl11-3-7, qtl11-4-9, qtl12-1-1, and qtl12-2-3, have not been previously reported. The qtl11-3-7 and qtl11-4-9 may be the two main effective QTL and resistant to 7 and 9 isolates, respectively. The results of the present study will be valuable for the fine mapping and cloning of these two new resistance genes.