Abstract Background Gastric cancer is one of most common malignancies in the world. Currently the prognostic prediction is entirely based on the TNM staging system. In this study, we evaluated ...whether metastatic lymph node ratio (rN) at the time of surgery would improve the prognostic prediction in conjunction with the TNM staging system. Methods This retrospective study includes 745 patients, who had been referred for surgery due to gastric cancer between 1995 and 2007 and had at least 15 lymph nodes examined at the time of surgery without preoperative treatment. Clinicopathologic features and overall survival were analyzed using univariate and multivariate modes to identify the risk factors for overall survival. Results Median overall survival of all patients analyzed is 57.8 months and 5-year overall survival is 49.5%. Tumor site, macroscopic type, pTNM stage, and rN stage are identified as independent prognostic factors. Increased positive lymph node ratio correlates with shorter survival in all patients and in each T and N stage. In stage III gastric cancer patients, rN stage shows additional prognostic value on overall survival ( p < 0.001). Conclusions rN stage is a simple and promising prognostic factor of gastric cancer after surgery in addition to the TNM stage system especially in stage III patients. But the independent prognostic value of rN stage in stage I, II and IV gastric cancer is yet to be determined.
•The flow boiling experiment are conducted in porous-wall (PW) microchannels.•The effect of mass flux, heat flux and vapor quality on microchannels are studied.•PW microchannels reduce the wall ...superheat for ONB and improve the CHF.•PW microchannels exhibit obvious heat transfer enhancement with pressure drop reduction.•The uniformity and stability of wall temperature are analyzed in PW microchannels.
In this work, we proposed a porous-wall (PW) microchannel heat sink, in which micro pin fin arrays were fabricated on sidewalls of rectangular microchannels by MEMS (Microelectrical Mechanical System) technique. High speed flow visualizations were performed simultaneously with heat transfer and pressure drop measurements to investigate the flow boiling characteristics of PW microchannel heat sink. Conventional rectangular (Rec) microchannel heat sink was also explored together as a comparison. Experiments were carried out with pure acetone liquid at inlet temperature of 30 °C, mass flux from 255 kg/(m2·s) to 843 kg/(m2·s), heat flux from 4 W/cm2 to 110 W/cm2 and the maximum vapor quality at the outlet of the channel was 0.88. Experimental results demonstrated that the PW microchannels reduce wall superheat of onset of nucleate boiling (ONB) and improve critical heat flux (CHF) compared to the Rec microchannels. Moreover, the PW microchannels show significant heat transfer enhancement, pressure drop reduction and mitigation of two-phase flow instability. The porous walls provide numerous nucleation sites and the intensive pin fins arrangements introduce significant wicking effect to maintain the liquid rewetting, which contribute to the above notable flow boiling enhancement.
A tunable stiffness and damping vibration isolator based on magnetorheological elastomers (MREs) is developed. In this isolator, four MRE elements are used as the tunable springs, whose stiffness can ...be controlled by varying the magnetic field. A voice coil motor, which is controlled by the relative velocity feedback of the payload, is used as the tunable damper of the isolator. Under the combined ON–OFF control, the proposed vibration isolator shows satisfying isolation effect. The experimental results indicate that the responses of the payload are suppressed significantly in comparison to the passive system. The transmissibility of the payload around the resonant frequency is decreased by 61.5%. The root mean square (RMS) value and the maximum value of the displacement responses of the payload are decreased by 36.0% and 50.0%, respectively. In addition, the RMS values and maximum values of the velocity responses are decreased by 45.4% and 52.5%, respectively.
•A novel porous-wall microchannels was designed and fabricated, in which the solid walls were replaced by the micro pin fin arrangements.•With the porous-wall inter-connect effect, the mass and ...pressure can be propagated between adjacent channels.•For semi-stable/moderate/severe unstable two-phase flow, the variation of wall temperatures was not in accordance with ΔP.
In this work, a porous-wall microchannel heat sink was designed and fabricated, and the wall regions were etched with the micro pin fin arrangement instead of solid walls. The porous-wall can be divided into three regions: the densely/intermediate densely/sparely pin fin region with the fin gap of 5 μm/7.5 μm/10 μm, respectively. Flow boiling tests in porous-wall microchannels were carried out at mass fluxes of 250–510 kg/(m2·s) and heat fluxes of 120–720 kW/m2. The effects of the porous-wall on suppressing the flow instabilities and manipulating the boiling flow were studied, and different boiling flow behaviors of pressure drops and temperatures as well as corresponding flow patterns were measured and observed. The experimental results showed that: (1) With the porous-wall inter-connect effect, the premature ONB (Onset of Nucleate Boiling) can be occurred, the nucleate boiling flow in whole channel can be triggered in less than 2 ms, the boiling flow instability can be suppressed, and the duration of two-phase flow can be prolonged; (2) The boiling instabilities in porous-wall microchannels were classified into four flow modes, and the temporal behaviors of temperatures and pressure drops corresponding to each flow instability mode were observed and analyzed. (3) By PSD (Power Spectral Density) combined with WT (Wavelet Transform) analysis method, the coupled wall temperature oscillations in each instability type were decoupled into different instability sub-types at different amplitudes and timescales. Moreover, the analysis of ms-timescale flow instability induced by the flow pattern transition helps to better understanding the dominant influence of the porous-wall on the resulting temperature oscillations.
•Novel heat sink with 4-ports and offset zigzag microchannel is designed.•4-ports configuration effectively reduce pressure drop and enhance heat transfer.•Zigzag channels enhance heat transfer, but ...not bring larger pressure drop.•4-port with Z improvise temperature uniformity and reduce pressure drop.•For fixed Pp, 4-ports with Z can meet larger heat dissipation than 2-ports and R.
For cooling specific chip of 2mm∗10mm, the 4-ports and offset zigzag microchannels are designed. The fluid flow and heat transfer characteristics of 4-ports silicon heat sinks with rectangle and zigzag microchannels have been investigated experimentally. Deionized water is employed as the cooling fluid with flow rates of 28–72ml/min. Results show the 4-ports heat sink can effectively reduce pressure drops and reduce temperature rising along the flow directions for the fixed flow rates. For 4-ports with rectangle microchannel, the pressure drops is decreased about 70% and average temperature also is reduced by 2.8°C. It can be interpreted that 4-ports structures reduce the length of channel and increase channel number, which leads to the flow velocity decreased by 0.5 times and the fluid distribution more uniform. Compared with 4-ports with rectangle microchannels, for 4-ports with zigzag microchannels heat sink, the pressure drop is reduced under the lower flow rates but increased slightly under larger flow rates. And temperatures of all flow rates are reduced, which is reduced by 3.8°C and pressure drop only increased 2.6kPa at flow rates of 72ml/min. It can be interpreted that zigzag cavities redevelop thermal boundary layer and enhance the fluid disturbance to make the fluid mixing better. Additional, zigzag cavities also enlarge heat transfer areas and reduce the fluid velocity by increasing flow cross-section areas. Under fixed pumping power, 4-ports with Z can meet the larger heat dissipation and smaller flow rates requirement.
The glioblastoma includes brain tumors, which are very aggressive in nature and are among the most common brain tumors in adults. Latest therapeutic avenues involve combination approach. However, the ...observed median survival is still no more than 15 months. Moreover, there is a scarcity of accurate pre-clinical model systems, which in turn resulted in limited treatment options for this disease. Cancer stem cells are attractive avenues in anticancer research against glioblastoma. Most of the recent studies are focused towards the identification of novel markers for cancer stem cells. The present review article is focused on two important markers in current research viz. Prominin-1 and NPM1 in glioblastoma.
Purpose: Non-steroidal anti-inflammatory drugs (NSAIDs) have generally been viewed as first-line therapy for axial spondyloarthritis (axSpA). Imrecoxib is a selective COX-2 inhibitor developed ...independently in China. At present, only one single-center RCT trial has shown that imrecoxib is equally effective as celecoxib in treating axSpA. Based on real-world data, our study aims to explore the efficiency of imrecoxib and TNF inhibitor (TNFi) combined with imrecoxib in treating axSpA. Patients and Methods: A total of 163 patients with axSpA who had more than two follow-up records in 6 months and treated with imrecoxib/celecoxib/TNFi combined with imrecoxib/TNFi combined with celecoxib from the First Affliated Hospital of Anhui Medical University SpA Real World Database (AHSpA) were selected for analysis of our study. The linear mixed model was used to compare efficacy indexes before and after treatment and between different groups, adjust baseline measurement value and follow-up time. The Kaplan-Meier survival analysis was used to identify the differences in cumulative clinical remission rates between groups with different treatment at the follow-up period. Results: Results showed that after treatment ASDAScrp was slightly improved in imrecoxib group and celecoxib group within 6 months (p < 0.05). CRP, ESR, BASDAI, ASDAScrp, BASFI, occiput to wall distance and finger foor distance all significantly improved in TNFi combined with imrecoxib group and TNFi combined with celecoxib group within 6 months (all p < 0.05). According to the Kaplan-Meier survival curve and Log rank test analysis, the clinical remission rate was not significantly different between different treatment during 24-month follow-up (all p > 0.05). Conclusion: ASDAScrp improved slightly within 6 months after treatment with imrecoxib, and TNFi combined with imrecoxib significantly improved multiple effect indexes in axSpA patients. The efficacy of imrecoxib and celecoxib in the treatment of axSpA is equivalent. Also, they have the same efficacy after being combined with TNFi. Keywords: axial spondyloarthritis, imrecoxib, celecoxib, TNF inhibitor
Gastric cancer is the fourth most common cancer worldwide and the leading cause of tumor-related death in China. Gastric cancer is a heterogeneous disease and therefore requires different treatments ...based on the subtype. We describe a patient who had gastric cancer with liver metastases. Biopsy and tumor analysis using the HercepTest revealed a human epidermal growth factor receptor 2 (HER2)-positive adenocarcinoma as confirmed by fluorescence in situ hybridization. The patient was treated with a regimen of trastuzumab, oxaliplatin, and S-1 (six cycles). When positron emission tomography findings suggested that the metastases had resolved, the patient underwent surgery. Histopathologically, no cancer cells were observed in the resected hepatic tissue. The patient underwent tumor resection surgery, during which the tumor and gastric lymph nodes with lesions were removed. The patient has remained disease-free for 3 months. Therefore, trastuzumab may be an effective agent in the chemotherapeutic treatment of liver metastases in patients with HER2-positive gastric adenocarcinoma.
This study proposes an improved microchannel heat sink with offset zigzag cavities to enhance boiling performance. Flow and heat transfer characteristics are experimentally investigated via a ...microscale boiling heat transfer visualization system using acetone as the working fluid. At mass fluxes of 285, 402, and 684 kg/(m2·s) and heat fluxes of 1.31–80.26 W/cm2, the effects of heat and mass fluxes on flow pattern, heat transfer, wall temperature, and pressure drop of zigzag microchannel heat sink are analyzed and compared with conventional rectangle microchannel heat sink. Results show that the fluctuating amplitude first increases and then decreases with the increment of heat fluxes, thereby causing a quasi-steady and unstable boiling with small fluctuations. Instability becomes increasingly severe for the nucleate boiling area moves toward the inlet and flow reversal intensity increases with heat fluxes under low heat flux. With heat flux increased furtherly. The proportion of steam in the channel increases to reduce fluctuations. Compared with the rectangular microchannel, the zigzag microchannel evidently enhances heat transfer characteristic with lower wall temperature at the onset of nucleate boiling (ONB), higher heat transfer coefficient (HTC) and critical heat flux (CHF) and improves boiling stability by suppressing flow reversal and reducing two-phase pressure drop. The mechanism of zigzag microchannel enhancement boiling performance can be attributed to (1) the improved disturbance of the working fluid, which enhances forced convective boiling heat transfer and mitigates bubble coalescence and flow reversal strength; (2) the continuously developing liquid film and improved wettability maintain a stable liquid film evaporation and delay partial dry out. Increase in mass flux can improve CHF and reduce pressure drop albeit with high wall temperature of ONB. The local HTC is enhanced, except for the low heat fluxes, because the bubbles are condensed by liquid and cannot grow to absorb heat at low heat fluxes.
•A microchannel with offset zigzag cavities is proposed.•Zigzag microchannel improves surface wettability and fluid disturbance, and forms a continuously developing liquid film.•Zigzag microchannel enhances heat transfer with reducing wall temperature at ONB and improving HTC and CHF.•Zigzag microchannel improves boiling stability with suppressing bubble combination and flow reversal strength.
Abstract We studied the effect of vasoactive intestinal peptide (VIP) on angiogenesis in the ischemic boundary area after focal cerebral ischemia. Adult male Sprague–Dawley rats underwent middle ...cerebral artery occlusion for 2 h. A single dose of VIP was given via i.c.v. injection at the beginning of reperfusion. Immunohistochemistry and Western blotting were performed to assay angiogenesis and brain levels of vascular endothelial growth factor (VEGF) protein, respectively. In addition, the expression of VEGF and its receptors (flt-1 and flk-1), as well as endothelial proliferation, was measured using rat brain microvascular endothelial cells. Immunohistochemical analyses revealed significant ( P <0.05) increases in the numbers of bromodeoxyuridine (BrdU) positive endothelial cells and microvessels at the boundary of the ischemic lesion in rats treated with VIP compared with rats treated with saline. Western blotting analysis showed that treatment with VIP significantly ( P <0.05) raised VEGF levels in the ischemic hemisphere. In addition, treatment with VIP increased flt-1 and flk-1 immunoreactivity in endothelial cells. In vitro , incubation with VIP significantly ( P <0.01) increased the proliferation of endothelial cells and induced the expression of VEGF, flt-1 and flk-1 in endothelial cells. The stimulatory effect of VIP on the proliferation of endothelial cells was significantly ( P <0.01) inhibited by SU5416, a selective inhibitor of VEGF receptor tyrosine kinase. Our data suggest that treatment with VIP enhances angiogenesis in the ischemic brain, and this effect may be mediated by increases in levels of VEGF and its receptors.
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