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Treatments enhancing angiogenesis for chronic cerebral hypoperfusion (CCH) are still in the research stage. Although encephalomyosynangiosis (EMS) is a common indirect anastomosis for the treatment of CCH, the effectiveness to promote angiogenesis is not satisfactory. Vascular endothelial growth factors (VEGF) is a cytokine found to specifically act directly on vascular endothelial cells, promote neovascularization, and enhance capillary permeability. However, the short half life and unstable property of VEGF underlies the need to explore available delivery system. In this study, poly (lactide-co-glycolide) (PLGA) was used to prepare VEGF controlled-release microspheres. In vitro and in vivo analysis of release kinetics showed that the microspheres could release VEGF continuously within 30 days. Then, modified chronic cerebral hypoperfusion rat model was established by ligation of bilateral internal carotid artery and one vertebral artery. At 14 days after ischemia, the EMS and the VEGF microspheres injection were performed. At 30 days after the injection, the result of Morris water maze displayed that combinating VEGF microspheres and EMS significantly ameliorated cognitive deficit after ischemia. We observed that combinating VEGF microspheres and EMS could further significantly increase cerebral blood flow. We speculated that this enhancement of cerebral blood flow was attributed to more angiogenesis induced by combination of VEGF microspheres and EMS, which verified by more collateral circulation with cerebral angiography and higher expression of CD31 or α-SMA. Our study demonstrated that combinating VEGF-PLGA controlled-release microspheres could significantly promote angiogenesis in EMS-based CCH rats model, providing new ideas for clinical treatment of CCH.

Refereed/Peer-reviewed P75 pan-neurotrophin receptor (p75NTR) is an important receptor for the role of neurotrophins in survival and death of neurons during development and after nerve injury. Our previous research found that the precursor of brain-derived neurotrophic factor (proBDNF) regulates pain as an inflammatory mediator. The current understanding of the role of proBDNF/p75NTR signaling pathway in inflammatory arthritis pain and rheumatoid arthritis (RA) is unclear. We recruited 20 RA patients, 20 healthy donors (HDs), and 10 osteoarthritis (OA) patients. Hematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) of proBDNF and p75NTR in synovial membrane were performed and evaluated. We next examined the mRNA and protein expression of proBDNF/p75NTR signaling pathway in peripheral blood mononuclear cells (PBMCs) and synovial tissue. ELISA and flow cytometry were assessed between the blood of RA patients and HD. To induce RA, collagen-induced arthritis (CIA) were induced in mice. We found over-synovitis of RA synovial membrane compared to OA controls in histologic sections. P75NTR and sortilin mRNA, and proBDNF protein level were significantly increased in PBMCs of RA patients compared with the HD. Consistently, ELISA showed that p75NTR, sortilin, tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and interleukin-10 (IL-10) levels in the serum of RA patients were increased compared with HD and p75NTR, sortilin were positively correlated with Disease Activity Score in 28 joints (DAS28). In addition, using flow cytometry we showed that the increased levels of proBDNF and p75NTR characterized in CD4+ and CD8+ T cells of RA patients were subsequently reversed with methotrexate (MTX) treatment. Furthermore, we found pathological changes, inflammatory pain, upregulation of the mRNA and protein expression of proBDNF/p75NTR signaling pathway, and upregulation of inflammatory cytokines in spinal cord using a well-established CIA mouse model. We showed intravenous treatment of recombinant p75ECD-Fc that biologically blocked all inflammatory responses and relieved inflammatory pain of animals with CIA. Our findings showed the involvement of proBDNF/p75NTR pathway in the RA inflammatory response and how blocking it with p75ECD-Fc may be a promising therapeutic treatment for RA.

At present, multiphase flow productivity calculation requires many parameters, and most of them only consider oil and gas two-phase flow, which is complicated and limited. Therefore, a reasonable productivity formula of condensate gas reservoir with producing water is needed. The three-zone model of condensate gas reservoirs is generally applied to the physical model for inferring productivity. On this basis, an improved model is established, which includes that different seepage characteristics are considered for different zones. Moreover, the effects of inclined angle and water production on gas wells are regarded as pseudo-skin factors and additional-skin factors. In addition, Zone I considers the effects of high-speed nonDarcy effect(HSND), starting pressure gradient, stress sensitivity, inclined angle and water production; Zone II is the same way excepting starting pressure gradient and stress sensitivity ; Zone III only considers the effects of inclined angle and water production. As a result, a productivity equation with multiple factors for condensate gas wells is established. Through analysing cases and influences in H gas reservoir X1 well, the HSND, starting pressure gradient, stress sensitivity and water production have a negative impact on gas well productivity, but the inclined angle is opposite. Founded that the starting pressure gradient impacts on productivity is less than the HSND because of the limited radius of Zone I; the impact of the HSND on productivity increases with the decreasing of bottom hole pressure; the impact of water production on gas well productivity is much higher. When the angle is over 60°, the effect of gas

Now there is not engough basic theory to explain the friction mechanism on the shear deformation zone and tool-workpiece deformation zone in the process of metal cutting.But the constant coefficient of friction model is not in accord with the actual cutting tool friction. So Friction law of micro friction process were studied by friction test and simulation, the friction model of micro - cutting are very important which can improve the micro-cutting mechanism, finite element modeling and Simulation of metal cutting process and etc.

Though the observation in micro cutting of 45 steel, the deformation zone of fracture characteristics was studied, and the corresponding cutting model was established; on dynamic tensile and situ observation of 45 steel by transmission electron microscopy , micro cutting ductile fracture process is simulated by the experiment on the steel tensile of 45 film sample, and the mechanism on initiation and propagation of crack in micro cutting fracture was studied with dislocation theory.

This paper makes an analysis of the essential reasons for a continuously high percentage of electrical fire occurrences in China. The analysis of the genesis of electric fires in the electric circuit is also described in the article. Based on the different genesis of electric fire in the electric circuit, different features, including short circuit, circuit overload, bad contact of the terminals, increasing of the contact resistance in the circuit, ageing and charging in the circuit and leakage current fault, are described in this paper. Corresponding methods of fire preventions & control to the different electric circuit faults are put out. With respect to different electrical fire genesis and features, an overall plan for electrical fire prevention & control in a low voltage distribution system is put forward here.

In this paper, fire risk has been analyzed to the daily electric power utilization, communication cabinet, battery cupboard and distribution cabinet installed in a communication room. Based on the present situation of the fire protection system in such kind of places, the design principles are offered. Also some suggestions to prevent fire attack from the daily electric power utilization, communication cabinet, battery cupboard and distribution cabinet in such kind of places are offered in this paper.

It analyses deeply the diffrence between micro cutting and conventional machine cutting from the mechanism of cutting surface formation in this paper, and building the micro cutting model , then analyses friction mechanism of micro cutting processing introduce a new micro friction model, this paper discusses interface micro friction characteristics in the process of micro cutting.

This paper analysis Griffith 's Theory and the metal theoretical fracture strength, thus introducing a line defect that existence in actual crystal — dislocation; And in-depth analysis the metal fracture dislocation mechanism in the micro cutting, and the formation and expand of the Fracture cracks , provides the theory basis for micro cutting