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The aim of the present study was to evaluate the association between a polymorphism (rs2910164) in the microRNA (miR)-146a precursor and the prognosis of glioblastoma multiforme (GBM), as well as to examine the possible underlying mechanism in a Chinese population. A total of 380 patients with histologically confirmed GBM were recruited between 2008 and 2012, and were genotyped for the rs2910164 polymorphism using Sanger sequencing. The Kaplan-Meier method was used to estimate overall survival (OS), and univariate and multivariate Cox proportional hazard regression analyses were used to evaluate the effect of miR-146a polymorphisms on OS. It was identified that the rs2910164 CC genotype was significantly associated with a decreased OS among the patients with GBM (P=0.002). It was confirmed that Notch1 and Notch2 were targets of miR-146a and it was demonstrated that the introduction of miR-146a mimic suppressed the levels of Notch1 and Notch2 to different extents, resulting in a reduced Notch1/Notch2 ratio with an increase in miR-146a mimic concentration in U251 cells. Additionally, resected tumor specimens were collected from 138 GBM patients and the expression levels of miR-146a, Notch1 and Notch2 were examined using reverse transcription-quantitative polymerase chain reaction and western blot analysis. Consistent with the in vitro study, lower levels of miR-146a, higher levels of Notch1 and Notch2, and a higher Notch1/Notch2 ratio were identified in the CC genotype group compared with those of the GG/GC group. In the present study, the rs2910164 C allele was found to be associated with a reduced survival rate in patients with GBM, and the observed association between the CC genotype and poorer prognosis of GBM was at least partially mediated by the decreased expression of miR-146a, which interfered with the balance of Notch1 and Notch2. [ABSTRACT FROM AUTHOR]

Background Currently, Posterior Short Segment Pedicle Screw Fixation is a popular procedure for treating unstable thoracolumbar/lumbar burst fracture. But progressive kyphosis and a high rate of hardware failure because of lack of the anterior column support remains a concern. The efficacy of different methods remains debatable and each technique has its advantages and disadvantages. Methods A consecutive series of 20 patients with isolated thoracolumbar/lumbar burst fractures were treated by posterior short segment pedicle screw fixation and transforaminal thoracolumbar/lumbar interbody fusion (TLIF) between January 2005 and December 2007. All patients were followed up for a minimum of 2 years. Demographic data, neurologic status, anterior vertebral body heights, segmental Cobb angle and treatment-related complications were evaluated. Results The mean operative time was 167 minutes (range, 150–220). Blood loss was 450 ~ 1200 ml, an average of 820 ml. All patients recovered with solid fusion of the intervertebral bone graft, without main complications like misplacement of the pedicle screw, nerve or vessel lesion or hard ware failure. The post-operative radiographs demonstrated a good fracture reduction and it was well maintained until the bone graft fusion. Neurological recovery of one to three Frankel grade was seen in 14 patients with partial neurological deficit, three grades of improvement was seen in one patient, two grades of improvement was observed in 6 patients and one grade of improvement was found in 6 patients. All the 6 patients with no paraplegia on admission remained neurological intact, and in one patient with Frankel D on admission no improvement was observed. Conclusion Posterior short-segment pedicle fixation in conjunction with TLIF seems to be a feasible option in the management of selected thoracolumbar/lumbar burst fractures, thereby addressing all the three columns through a single approach with less trauma and good results. [ABSTRACT FROM AUTHOR]

Abstract: This paper exploits the applicability of the state-of-the-art Internet router buffer allocation wisdoms in the context of TCP-Friendly Rate Control (TFRC) protocol through extensive numerical simulations. The assessment of buffer allocation is carried out for evaluating network performance in terms of resource utilization, packet delay and loss rate, and the result highlights the deficits of direct application of existing allocation strategies for TFRC protocol. As a result, this paper presents additional analytical remarks on the characteristics of TFRC protocol buffer allocation through a comparison with TCP protocol. [Copyright &y& Elsevier]