Giant aneurysm of the bilateral vertebrobasilar junction treated by pipeline and coils: A case report and literature review.

Giant aneurysm of the posterior circulation is associated with a higher risk of rupture compared with that of the anterior circulation. Furthermore, surgical clipping and interventional embolization for giant aneurysm of the posterior circulation are more difficult and complex to perform. The present study reported on the case of a 26-year-old female who exhibited a giant spherical aneurysm of the vertebrobasilar junction (VBJ) with a maximum diameter of ~35 mm that caused cervical discomfort. In addition, the patient experienced symptoms including left-sided walking and hoarseness caused by the compression of the brainstem and the posterior cranial nerves. The risks associated with performing surgery in this area are high and the prognosis is mainly poor. The patient of the present study was treated using the Pipeline Flex device with coil embolization. As a giant aneurysm of the VBJ simultaneously affects the bilateral vertebral arteries (VAs) and basilar artery, it is a unique condition and the treatment strategy must be personalized. Based on an analysis of the hemodynamic influence on the aneurysm in the present case, the Pipeline was placed through the left VA, the coils were packed through the right VA, and finally, the right VA was proximally occluded. At 7 months after embolization, the patient's modified Rankin scale score was 1 point. Upon analysis of the hemodynamic influence on the aneurysm of the VBJ, the VA with the larger shear force on the wall of the aneurysm was selected for occlusion to simplify the treatment of the aneurysm and to maximize the probability to achieve recovery.

Compensation of Rotary Encoders Using Fourier Expansion-Back Propagation Neural Network Optimized by Genetic Algorithm.

The measurement accuracy of the precision instruments that contain rotation joints is influenced significantly by the rotary encoders that are installed in the rotation joints. Apart from the imperfect manufacturing and installation of the rotary encoder, the variations of ambient temperature could cause the angle measurement error of the rotary encoder. According to the characteristics of the 2π periodicity of the angle measurement at the stationary temperature and the complexity of the effects of ambient temperature changes, the method based on the Fourier expansion-back propagation (BP) neural network optimized by genetic algorithm (FE-GABPNN) is proposed to improve the angle measurement accuracy of the rotary encoder. The proposed method, which innovatively integrates the characteristics of Fourier expansion, the BP neural network and genetic algorithm, has good fitting performance. The rotary encoder that is installed in the rotation joint of the articulated coordinate measuring machine (ACMM) is calibrated by using an autocollimator and a regular optical polygon at ambient temperature ranging from 10 to 40 °C. The contrastive analysis is carried out. The experimental results show that the angle measurement errors decrease remarkably, from 110.2″ to 2.7″ after compensation. The mean root mean square error (RMSE) of the residual errors is 0.85″.

Enhanced cyclic adenosine monophosphate production by Arthrobacter A302 through rational redistribution of metabolic flux.

Cyclic adenosine monophosphate (cAMP) was synthesized through the purine salvage synthesis pathway by Arthrobacter A302. Results showed that hypoxanthine was the best of the precursors, and the cAMP concentration reached 4.06 g/L. For inhibition of the glycolytic pathway, sodium fluoride was found the optimal effector, which was further studied on cAMP production. With the addition of 0.4 g/L of sodium fluoride, the maximal cAMP concentration reached 11.04 g/L, and the concentrations of lactic acid, alpha-ketoglutarate and citric acid were decreased by 77%, 86% and 76%, respectively. Meanwhile, the specific activities of glyceraldehyde 3-phosphate dehydrogenase, phosphofructokinase and pyruvate kinase were decreased by 66%, 61%, and 46%, respectively. By contrast the activity of 6-phosphoglucose dehydrogenase was increased by 100%, which demonstrated the redistribution of metabolic flux. This is the first study to reveal the regulatory mechanisms of different effectors on cAMP production among the EMP pathway, HMP pathway and TCA cycle.

Medium optimization for the production of cyclic adenosine 3',5'-monophosphate by Microbacterium sp. no. 205 using response surface methodology.

Response surface methodology was employed to optimize medium composition for the production of cyclic adenosine 3',5'-monophosphate (cAMP) with Microbacterium sp. no. 205. A fractional factorial design (2(11-7)) was applied to evaluate the effects of different components in the medium. K(2)HPO(4), MgSO(4) and NaF were found to significantly influence on the cAMP production. The steepest ascent method was used to access the optimal region of the medium composition. The concentrations of the three factors were optimized subsequently using central composite design and response surface methodology. The optimal medium composition to achieve the optimal cAMP production was determined (g/L): K(2)HPO(4), 12.78; MgSO(4), 3.53 and NaF, 0.18. The corresponding cAMP concentration was 8.50 g/L, which was about 1.8-fold increase compared with that using the original medium. Validation experiments were also carried out to prove the adequacy and the accuracy of the model obtained. The cAMP fermentation in 5L fermenter reached 9.87 g/L.