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From a biomechanical point of view, the femoral neck system is a valid alternative to treat unstable femoral neck fractures, representing the advantages of a minimally invasive implant with comparable stability to the 2 DHS systems and superior to cannulated screws.

The effects of selection on genome variation were investigated and visualized in tomato using a high-density single nucleotide polymorphism (SNP) array. 7,720 SNPs were genotyped on a collection of 426 tomato accessions (410 inbreds and 16 hybrids) and over 97% of the markers were polymorphic in the entire collection. Principal component analysis (PCA) and pairwise estimates of F st supported that the inbred accessions represented seven sub-populations including processing, large-fruited fresh market, large-fruited vintage, cultivated cherry, landrace, wild cherry, and S. pimpinellifolium. Further divisions were found within both the contemporary processing and fresh market sub-populations. These sub-populations showed higher levels of genetic diversity relative to the vintage sub-population. The array provided a large number of polymorphic SNP markers across each sub-population, ranging from 3,159 in the vintage accessions to 6,234 in the cultivated cherry accessions. Visualization of minor allele frequency revealed regions of the genome that distinguished three representative sub-populations of cultivated tomato (processing, fresh market, and vintage), particularly on chromosomes 2, 4, 5, 6, and 11. The PCA loadings and F st outlier analysis between these three sub-populations identified a large number of candidate loci under positive selection on chromosomes 4, 5, and 11. The extent of linkage disequilibrium (LD) was examined within each chromosome for these sub-populations. LD decay varied between chromosomes and sub-populations, with large differences reflective of breeding history. For example, on chromosome 11, decay occurred over 0.8 cM for processing accessions and over 19.7 cM for fresh market accessions. The observed SNP variation and LD decay suggest that different patterns of genetic variation in cultivated tomato are due to introgression from wild species and selection for market specialization.

Patella infera is a known complication of high tibial osteotomy (HTO) that can cause anterior knee pain due to excessive stresses associated with abnormal patellofemoral (PF) joint biomechanics. However, the translation of these abnormal biomechanics to native cartilage pressure has not been explored. The present study was designed to compare the PF contact pressures of three different HTOs in a human cadaveric model of valgus tibiofemoral correction. Nine fresh cadaveric knees underwent (1) medial opening wedge (OWHTO) with a proximal tuberosity osteotomy (PTO), (2) OWHTO with a distal tuberosity osteotomy (DTO), and (3) a lateral closing wedge (CWHTO). The specimens were mounted in a custom knee simulation rig, with muscle forces being simulated using a pulley system and weights. The PF contact pressure was recorded using an electronic pressure sensor at 15 degrees , 30 degrees , 60 degrees , 90 degrees , and 120 degrees of knee flexion, with results of the intact knees obtained as relative control. Compared to the intact knee, the DTO OWHTO and CWHTO did not significantly (P > 0.05) influence PF pressure at any flexion angle. On the other hand, PTO OWHTO lead to a significant elevation in PF cartilage pressure at 30 degrees (P < 0.05), 60 degrees (P < 0.005), and 90 degrees (P < 0.0005) knee flexion. We conclude from these results that DTO OWHTO maintains normal joint biomechanics and has no significant effect on PF cartilage pressure. In patients who complain of pre-existing anterior knee pain, DTO OWHTO or CWHTO should be considered.

We have generated an ultra-high-density genetic map for lettuce, an economically important member of the Compositae, consisting of 12,842 unigenes (13,943 markers) mapped in 3696 genetic bins distributed over nine chromosomal linkage groups. Genomic DNA was hybridized to a custom Affymetrix oligonucleotide array containing 6.4 million features representing 35,628 unigenes of Lactuca spp. Segregation of single-position polymorphisms was analyzed using 213 F7:8 recombinant inbred lines that had been generated by crossing cultivated Lactuca sativa cv. Salinas and L. serriola acc. US96UC23, the wild progenitor species of L. sativa. The high level of replication of each allele in the recombinant inbred lines was exploited to identify single-position polymorphisms that were assigned to parental haplotypes. Marker information has been made available using GBrowse to facilitate access to the map. This map has been anchored to the previously published integrated map of lettuce providing candidate genes for multiple phenotypes. The high density of markers achieved in this ultradense map allowed syntenic studies between lettuce and Vitis vinifera as well as other plant species.

For the detection of syndesmotic instability at the site of ankle fractures on stress radiographs, the lateral stress test appeared to be superior to the external rotation stress test in this cadaver model.

Background:The bone remodeling sequence after bone fracture changes the concentrations of biochemical bone markers, but the relationships of fracture size and of healing time to changes in biomarkers are unclear. The present pilot study was undertaken to determine the changes found in serum bone markers after plate osteosynthesis of closed distal tibial and malleolar fractures during a study period of 24 weeks.