High Axle Research Articles

Performance Evaluation of Polymer Modified Asphalt Mixtures

Attention has been increasing towards the use of polymer modified asphalt, because conventional asphalt mixtures cannot resist the high axle loads and tire pressures. Several classes of modified binders have been used in asphalt pavements. The main objective of this research was to evaluate the effect of adding several types of polymers on asphalt cement and asphalt mixtures. Experimental program involved two phases. The first phase was modifying the asphalt using six types of polymers then evaluating the properties of the modified asphalt. The second phase was evaluating the effect of binder modification on Marshall mix design and indirect tensile strength of the asphalt concrete mixtures. It was found that the optimum percentage of PVC, plastic bags and novolac was 4%, and the optimum percentage of HDPE was 5% by weight of asphalt. These percentages caused increase in kinematic viscosity, stability, and indirect tensile strength and caused reduction in penetration.

Targeted Inhibition of Axl Primes Chronic Lymphocytic Leukemia B-Cells for Apoptosis: Synergistic/Additive Effects in Combination with Bruton Tyrosine Kinase Inhibitors

Introduction: B-cell chronic lymphocytic leukemia (CLL) is an incurable disease despite that still requires options for treatment despite recent advances with BTK therapy. We previously found that Axl receptor tyrosine kinase (RTK), a member of the TAM (Tyro3, Axl, MER) family of RTKs, plays a critical role in CLL B-cell survival (Blood 2011, 117:1928). Here, we explored the levels of apoptosis induction of CLL B-cells using a novel high-affinity Axl inhibitor as a single agent or in combination with BTK inhibitors.Methods: Expression/activation status of the Tyro3, Axl and MER in CLL B-cells was evaluated by Immunoprecipitation/Western blots. Cells were treated with a high-affinity orally bioavailable Axl inhibitor TP-0903 (Tolero Pharmaceuticals) or FGFR inhibitor TKI-258 (Novartis) with or without the presence of CLL bone marrow stromal cells (BMSCs). Impact of Axl or FGFR signal inhibition on CLL B-cell survival was also evaluated by flow cytometry after staining with annexin V/propidium iodide. Finally, cells were exposed to TP-0903 in combination with BTK inhibitors to determine any synergistic/additive effects of the combination in induction of apoptosis. Combination index (CI) of two agents was calculated using the method of Chou and Talalay, 1984.Results: Although we defined pro-survival role of Axl in CLL B-cells, contribution of other members of the TAM family of RTKs including Tyro3 and MER to prolonged survival of the leukemic B-cells remains largely undefined. In this study we found that CLL B-cells overexpress Tyro3, but not MER, and that Tyro3 is constitutively phosphorylated. Interestingly, immunoprecipitation of Tyro3 from CLL B-cell lysates shows retention of highly active Axl in the immune complex suggesting that these two RTKs either heterodimerize or form a molecular complex in CLL B-cells.Our earlier work found that Axl regulates multiple cell survival signaling pathways including PI3K/AKT and Src and that, Axl inhibition using a first generation Axl inhibitor induced apoptosis in CLL B-cells (Blood 2011, 117:1928). Thus, we hypothesized that targeting Axl using a very high affinity Axl inhibitor would induce even higher levels of apoptosis in CLL B-cells compared to the first generation Axl inhibitor. To address this, we utilized a high-affinity orally bioavailable Axl inhibitor TP-0903 to generate preliminary information on its efficiency to specifically target Axl and the level of apoptosis induction in CLL B-cells. Indeed TP-0903 as a single agent induced a robust apoptotic cell death in CLL B-cells within 24 hours of exposure at nanomolar doses, which are easily achievable in vivo (information provided by Tolero Pharmaceuticals). Interestingly, while TP-0903 effectively reduces phosphorylation on Axl in CLL B-cells, it was unable to target P-Tyro3 suggesting that Axl is likely the predominant RTK of the TAM family in CLL B-cells. A marked reduction of the anti-apoptotic proteins Mcl-1, Bcl-2, XIAP and upregulation of the pro-apoptotic protein BIM in CLL B-cells via activation of its upstream regulator FOXO3a were noted as a result of inhibition of P-Axl and its downstream signaling pathways, P-AKT/P-Src. Importantly, TP-0903 was able to overcome CLL BMSC mediated protection of the leukemic B-cells from apoptosis induction. Given the observed robust induction of apoptosis with TP-0903 and the known impact of BTK inhibitors on CLL patient clinical outcome, we then exposed CLL B-cells to TP-0903 in combination with two BTK inhibitors that included Ibrutinib and a reversible BTK inhibitor TP-4216 (a kind gift from Tolero Pharmaceuticals). Based on the CI values, we found that the in vitro combination of TP-0903 and Ibrutinib showed additive effects in CLL B-cells from 6 of 11 CLL patients, CLL B-cells from the remaining 5 CLL patients showed antagonistic effects (Fig. 1A). However, we observed synergistic effects of TP-0903 in combination with TP-4216 in the induction of apoptosis in CLL B-cells from 2 of 10 patients and additive effects in CLL B-cells from 6 patients (Fig. 1B). Cells from the remaining 2 patients exhibited a slightly antagonisticeffect.Conclusion: In total, these results suggest that TP-0903 is quite effective in inducing robust CLL B-cell apoptosis as a single agent even at a nanomolar concentration and its combination with the reversible BTK inhibitor TP-4216 could be an effective and unique strategy for the treatment of CLL patients. [Display omitted] DisclosuresWarner:Tolero Pharmaceuticals: Employment, Equity Ownership, Patents & Royalties. Bearss:Tolero Pharmaceuticals: Employment. Shanafelt:Genentech: Research Funding; GlaxoSmithKline: Research Funding; Celegene: Research Funding; Cephalon: Research Funding; Pharmacyclics/Jannsen: Research Funding; Hospira: Research Funding; Polyphenon E Int’l: Research Funding. Kay:Genetech: Research Funding; Pharmacyclics: Research Funding; Hospira: Research Funding; Celgene: Membership on an entity’s Board of Directors or advisory committees; Gilead: Membership on an entity’s Board of Directors or advisory committees.

The role of AXL and the in vitro activity of the receptor tyrosine kinase inhibitor BGB324 in Ewing sarcoma.

New targets for Ewing sarcoma (ES) patients are urgently needed. Therefore, we investigated the expression and genetic aberrations of the oncogenic receptor tyrosine kinase (RTK) AXL in ES and determined the efficacy of AXL targeting on cell viability and migration. First, AXL and Gas6 (ligand) mRNA expression was determined by RT-PCR on 29 ES samples. Low, medium and high AXL mRNA expression was observed in 31% (n = 9), 48% (n = 14) and 21% (n = 6) of samples. Gas6 was abundantly present in all specimens. We next tested AXL protein expression immunohistochemically in 36 tumors (primary, post-chemotherapy, metastasized and relapsed samples) from 25 ES patients. Low, medium and high AXL protein expression was observed in 17% (n = 6), 19% (n = 7) and 36% (n = 13) of samples. In primary tumors (n = 15), high AXL expression correlated significantly with a worse overall survival compared to patients with lower expression (61 vs. 194 months, p = 0.026). No genetic aberrations were detected in the AXL RTK domain (n = 29). The AXL-inhibitor BGB324 affected viability (IC50 0.79-2.13 μmol/L) and migratory potential of all tested ES cell lines in vitro (n = 5-6). BGB324 chemosensitized chemotherapy-resistant ES-4 cells to vincristine and doxorubicin. These data suggest that AXL is a potential novel, druggable therapeutic target in ES.

Abstract 4403: Preclinical evaluation of LY2801653, an orally bioavailable small molecule oncokinase inhibitor, in cholangiocarcinoma models

Abstract Cholangiocarcinoma (CCA) is an aggressive and locally invasive biliary tract malignancy with a poor prognosis and no approved drug treatment. LY2801653 is an orally bioavailable small molecule oncokinase inhibitor1 of MET, a receptor reported to be dysregulated and correlated with a poor outcome in CCA. We evaluated additional oncotargets of LY2801653 (MET/HGF, pMET, AXL/pAXL, the MKNK1/2 substrate p-eIF4E, and ROS1) in 7 CCA cell lines (EGI-1, TFK-1, SNU245, SNU478, SNU869, SNU1079, and SNU1196) and 5 CCA patient-derived mouse xenograft (PDX) tumors. Cell line expression of MET, EGFR and p-eIF4E were evaluated by western blot. Although HGF expression was not detected in any of the cell lines by ELISA, pMET was detected in 5 cell lines (not in TFK-1 or SNU1079). ROS1 fusion was not detected in the 7 cell lines using break-apart FISH probes. Very high AXL and pAXL were detected in the SNU1196 line by western blot. Despite the high levels of pAXL, further increases in pAXL were noted after addition of its ligand, Gas6. In the SNU1196 cell line, pAXL expression and cell proliferation were completely inhibited by LY2801653, but not by a MET-specific inhibitor PF4217903. HGF-induced SNU1196 cell migration was inhibited equally well by LY2801653 and PF4217903. Unlike CCA cell line derived mouse xenograft tumors, the 5 PDX tumors retained prominent desmoplastic stroma. As analyzed by immunohistochemistry (IHC), MET was highly expressed in 3 of the 5 PDX tumors, and high levels of p-eIF4E were expressed in all 5. Increased AXL expression (IHC) appeared to be associated with more poorly differentiated PDX tumors. LY2801653 demonstrated potent in vivo anti-tumor activity in several CCA xenograft models. In a xenograft mouse model with the extrahepatic CCA derived EGI-1 cell line, treatment with LY2801653 at 24 mg/kg dosed twice daily resulted anti-tumor effect of 38.5% (% treated/control). In the SNU869 extrahepatic CCA cell line-derived xenograft mouse model, combination treatment with LY2801653 (12 mg/kg twice daily) and either cisplatin (5 mg/kg once weekly) or gemcitabine (60 mg/kg once weekly) resulted in an additive anti-tumor effect as compared to LY2801653 alone. Moreover, the combination of LY2801653 with gemcitabine resulted in tumor regression in this model. In vivo studies are ongoing with LY2801653 in the extrahepatic SNU1196 CCA cell line-derived xenograft model as well as two of the PDX models. The preclinical data in this study support the ongoing phase 1 clinical evaluation of LY2801653 in cholangiocarcinoma patients (trial I3O-MC-JSBA, NCT01285037). (1 - Yan et al. Invest New Drugs 2013;31:833-44). Citation Format: Sau-Chi Betty Yan, Suzane L. Um, Victoria L. Peek, Megan N. Thobe, Kelly M. Credille, Jennifer R. Stephens, Jason R. Manro, Darryl W. Ballard, Jessica A. Baker, Joel D. Cook, Bruce W. Konicek, Jeremy R. Graff, Timothy R. Holzer, Richard A. Walgren. Preclinical evaluation of LY2801653, an orally bioavailable small molecule oncokinase inhibitor, in cholangiocarcinoma models. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4403. doi:10.1158/1538-7445.AM2014-4403

Yes-associated protein 1 (YAP1) promotes human gallbladder tumor growth via activation of the AXL/MAPK pathway

The transcriptional coactivator Yes-associated protein 1 (YAP1), a key regulator of cell proliferation and organ size in vertebrates, has been implicated in various malignancies. However, little is known about the expression and biological function of YAP1 in human gallbladder cancer (GBC). In this study we examined the clinical significance and biological functions of YAP1 in GBC and found that nuclear YAP1 and its target gene AXL were overexpressed in GBC tissues. We also observed a significant correlation between high YAP1 and AXL expression levels and worse prognosis. The depletion of YAP1 using lentivirus shRNAs significantly inhibited cell proliferation by inducing cell cycle arrest in S phase in concordance with the decrease of CDK2, CDC25A, and cyclin A, and resulted in increased cell apoptosis and invasive repression in GBC cell lines in vitro. Furthermore, knockdown of YAP1 also inhibited tumor growth in vivo. Additionally, we demonstrated that the activation of the AXL/MAPK pathway was involved in the oncogenic functions of YAP1 in GBC. These results demonstrated that YAP1 is a putative oncogene and represents a prognostic marker and potentially a novel therapeutic target for GBC.

The Role of Axl in Ewing Sarcoma

ABSTRACT Aim: Ewing sarcoma (ES) is an aggressive form of primary bone cancer affecting mainly children and young adults. Despite intensive multimodal treatment, survival has not improved much during the last decade and therapeutic options in second line are scarce. Therefore, the search for novel, targeted therapeutic strategies has a high priority. Here, we investigated for the first time the expression and genetic aberrations of AXL, an oncogenic receptor tyrosine kinase (RTK), in ES and determined the efficacy of AXL-targeting on cell viability and migration in vitro. Methods: AXL and Gas6 (ligand) mRNA expression were determined by RT-PCR on 29 fresh-frozen ES patient samples. AXL protein expression was determined immunohistochemically in 36 tumors (primary tumors, post-chemotherapy resections, metastases and relapses) from 25 ES patients. Kaplan-Meier analysis (log-rank test) was performed to draw and evaluate the significance of survival curves. The AXL RTK domain and Gas6 were sequenced in 29 ES tumors. Six ES cell lines (ES1, ES2, ES4, ES7, ES8 and EW8) were treated in vitro with the specific AXL-inhibitor BGB324 (R428) and viability was analyzed with MTT-assays. In vitro migration assays were performed to investigate effects of BGB324 on ES cell migration. Results: Low, medium and high AXL mRNA expression was observed in 31% (n=9), 48% (n=14) and 21% (n=6) of ES samples, respectively. Gas6 was abundantly present in all specimens. Low, medium and high AXL protein expression was observed in 16% (n=6), 18% (n=7) and 34% (n=13) of ES samples. In primary tumors (n=15), high AXL expression correlated significantly with a worse overall survival (OS) compared to patients with lower expression (61 vs. 194 months, p=0.026). No genetic aberrations were observed in the AXL RTK domain or Gas6. BGB324 dose-dependently affected ES cell viability (IC50 0.79 - 2.13 mmol/L) and migratory potential (∼2 times delayed wound closure) in vitro. Conclusions: Our data suggest that AXL is a potential novel therapeutic target in ES. We are currently examining the effects of BGB324 on human derived ES xenografts in vivo. Because AXL-targeting drugs, such as BGB324, entered the phase of clinical trials, AXL targeting may potentially be of interest for further exploration in the clinical ES setting. Disclosure: All authors have declared no conflicts of interest.

Experimental investigation by laser ultrasonics for high speed train axle diagnostics

The present paper demonstrates the applicability of a laser-ultrasonic procedure to improve the performances of train axle ultrasonic inspection. The method exploits an air-coupled ultrasonic probe that detects the ultrasonic waves generated by a high-power pulsed laser. As a result, the measurement chain is completely non-contact, from generation to detection, this making it possible to considerably speed up inspection time and make the set-up more flexible. The main advantage of the technique developed is that it works in thermo-elastic regime and it therefore can be considered as a non-destructive method.The laser-ultrasonic procedure investigated has been applied for the inspection of a real high speed train axle provided by the Italian railway company (Trenitalia), on which typical fatigue defects have been expressly created according to standard specifications. A dedicated test bench has been developed so as to rotate the axle with the angle control and to speed up the inspection of the axle surface. The laser-ultrasonic procedure proposed can be automated and is potentially suitable for regular inspection of train axles.The main achievements of the activity described in this paper are:–the study of the effective applicability of laser-ultrasonics for the diagnostic of train hollow axles with variable sections by means of a numerical FE model,–the carrying out of an automated experiment on a real train axle,–the analysis of the sensitivity to experimental parameters, like laser source – receiving probe distance and receiving probe angular position,–the demonstration that the technique is suitable for the detection of surface defects purposely created on the train axle.

Influence of Construction of Railway Superstructure on Railway Quality

The operation of railway tracks is historically confirmed that the classic structure of the railway superstructure is capable to ensure operational capability of standard railway tracks for a relatively long period of time (railways tracks to speed of 160 km.h-1). Such a railway track and its track is considered the railway track with a classic structure of the railway superstructure, where track removal is stored in the ballast. In the case of high operating and axle load, increasing track speed and requirements for safety of operation, which are associated with high requirements on the track geometry, it appears that such structure has its operational (in terms of guaranteeing the long-term safety and reliability of the railway track) and economic (in terms of the cost of maintenance of railway track) limits. "Floating" placement of the track removal during each passage of a rail vehicle, or train leads to the growth of dynamic horizontal and vertical forces that cause gradual degradation of track geometry, what subsequently leads to restless journey of moving rail vehicles. Elimination of imperfections in track geometry - the quality of the railway track - forces the operators to remove such imperfections of railway track in time and financially consuming maintenance work in certain periods. However, it is sufficient if only the weakest element of classic railway superstructure is replaced in the railway, and it is the track ballast using other more appropriate component representing no elastic and plastic behaviour. The structure is such replacement, in which the track removal is concreted (monolithic structure) or stored on a concrete or asphalt bearing layer (layered structure), namely structural design, which is referred to as unconventional railway superstructure. The structure of railway superstructure is characterized by cross sleepers used in a modified shape or they are not part of it at all. Currently, thus conceived railway track is referred to as a slab track (hereinafter referred to as the "ST"), which requires flexibility of the railway superstructure for the system of the wheel/rail secured using elastic elements disposed between the rail and the sleeper and/or under the sleeper. In general, the structure of ST has been currently applied mainly to high-speed track and the tracks that have high operational load, where the cost of maintaining the track with the classic structure of the railway superstructure strongly grows. At the same time, however, this structure also promotes in the upgraded sections of the standard tracks (track speed to 160 km.h-1), especially in track sections conducted in tunnels, as there are located the required properties of the ballast that do not demonstrate subsidence. The subgrade without a drop also offers for application of the ST structure bridges, and therefore, the application of this structure is also possible in these track sections.

Reliability and measurement accuracy of a condition monitoring system in an extreme climate: A case study of automatic laser scanning of wheel profiles

The Iron Ore Line (Malmbanan) is a 473 km long track section located in northern Sweden and has been in operation since 1903. This track section stretches through two countries, namely Sweden and Norway, and the main part of the track runs on the Swedish side, where the owner is the Swedish Government and the infrastructure manager is Trafikverket (the Swedish Transport Administration). The ore trains are owned and managed by the freight operator and mining company LKAB. Due to the high axle load exerted by transportation of the iron ore, 30 tonnes, and the high demand for a constant flow of ore and pellets, the track and wagons must be monitored and maintained on a regular basis. The condition of the wagon wheel is one of the most important aspects in this connection, and here the wheel profile plays an important role. For this reason an automatic laser-based wheel profile monitoring system (WPMS) has been installed on this line using a system lifecycle approach that is based on the reliability, availability, maintainability and safety (RAMS) approach for railways. The system was prepared and installed and is being operated in a collaborative project between the freight operator and infrastructure manager. The measurements are used to diagnose the condition of the wheels, and to further optimize their maintenance. This paper presents a study of the concepts and ideas of the WPMS, and the selection, installation and validation of the equipment using a system lifecycle approach that is based on RAMS for railways. Results from the profile measurements and validation are shown. The system’s reliability during performance in extreme climate conditions, with severe cold and large quantities of snow, is presented. Then the benefits, perceived challenges and acquired knowledge of the system are discussed, and an improved V-model for the lifecycle approach is presented.

MP28-04 AXL IS A NOVEL PROGNOSTIC MARKER IN UPPER URINARY TRACT UROTHELIAL CARCINOM

INTRODUCTION AND OBJECTIVES: There are few molecular markers which are known to predict a poor prognosis in upper tract urothelial carcinomas (UTUC). Axl, which is in the TAM family of receptor tyrosine kinases, has been shown to be associated with tumor progression and cancer metastasis in some types of cancer, although the association with UTUC is still not clear. We therefore investigated the biological significance of Axl on UTUC outcome. METHODS: The protein expression of Axl by immunohistochemistry and its correlation with clinicopathologic features were investigated in surgical specimens obtained from 167 patients who had been surgically treated for UTUC at our institution. The mean follow-up period was 81.8 (1-291) months. The immunoreactivity for Axl was assessed independently by a single uropathologist. RESULTS: Axl labeling was strong in 85 of 167 (55%) cases and was weak in 82 of 167 (45%) cases. Overall strong positivity of Axl expression was statistically significantly associated with high grade tumors (p1⁄40.004), positive lymphovascular invasion (LVI) (p1⁄40.001), and occurrence of postoperative metastasis (p<0.001). In univariate analysis, patients with high pathological stage (p<0.001), high grade tumor (p<0.001), LVI positive (p<0.001), or strong Axl immunostaining (p<0.001) had a significantly lower rate of disease-specific survival. In multivariate analysis, high pathological stage (p1⁄40.010), high grade tumor (p1⁄40.012), and strong Axl immunostaining (p1⁄40.047) were statistically significant factors which predicted disease-specific survival. Using the 3 statistically significant variables in multivariate Cox regression analysis, we developed a prognostic factor-based model for risk stratification (Figure 1). Based on the odds ratio (OR) of diseasespecific survival, patients were divided into 3 risk groups: low (OR 1.00-5.23, 87 patients), intermediate (OR 7.01-9.07, 35 patients), and high (OR 18.2, 45 patients). The 3-year disease-specific survival rate was 90.3% in the low-risk group, 72.4% in the intermediate-risk group, and 35.7% in the high-risk group. The differences across groups were significant (low-risk vs. intermediate risk: p1⁄4 0.033, intermediate risk vs. high-risk: p<0.001, low-risk vs. high-risk: p<0.001). CONCLUSIONS: Axl protein expression is highly associated with tumor progression and metastasis of UTUC and might be a strong prognostic marker in UTUC patients treated by radical nephroureterectomy.

Fatigue Analysis of the Rail Underhead Radius under High Axle Load Conditions

An evaluation of the potential risk of fatigue damage at the rail underhead radius (UHR) due to the occurrence of a short duration tensile stress peak, as a wheel passes over, has been examined. The tensile stress peak is mainly due to the localised bending of the rail head-on-web and its magnitude is associated with the contact position, lateral and vertical forces and rail head wear (HW). The stresses at the underhead radius have been explored using the finite element method (FEM). The Dang Van (DV) criterion, implemented as a customised computer programme, was used to identify the fatigue damage at the UHR. Fatigue behaviour under heavy haul conditions was compared for heat-treated low alloy, euctectoid and hypereutectoid rail grades in order to predict allowable rail head wear limits.

High-Performance LC Resonant Amplifier Design and Implementation

The work mainly by the front level attenuator, the LC tuned amplifier, the push-pull output stage is composed. The first level weakens 40dB fixedly through pi the attenuator realization. Front the double grid field effect manages 3SK223 to make the level to increase the controllable LC tuned amplifier, the LC resonance by double harmonious and the list harmonious cascade way, enhanced the system selectivity. The complete machine gain is bigger than the 80dB, AGC control area to achieve above 60dB.The output stage uses the low pressure high electric current high speed axle to the axle structure integration operational amplifier OPA2354 push-pull transformer coupling output, sharpened the belt load capacity greatly. In order to reduce the amplifier as far as possible the noise and ceases the high frequency auto excitation, this design has adopted the power source filter, the shield, electromagnetic compatibility, the interstate coupling, the impedance matching and so on many kinds of measures. After the test, this plan has completed completely the basic function and the expansion function. Sweeps the frequency source turning on input end after CPLD self-made DDS, May very convenient see the system frequency response on the oscilloscope.

Optimisation of vehicle dynamics via torque vectoring for space optimised electric vehicles

Available space optimised packaging of the drivetrain components can lead to unconventional wheel axle loads, which have to be taken into account for the design of the vehicles’ dynamics. The BMW Group Research and Technology developed in cooperation with the German Aerospace Institute (DLR) and the Institute of Control Systems (IRS) within the Karlsruhe Institute of Technology (KIT) a control concept for torque vectoring. In spite of the challenge of high rear axle loads, attractive and at the same time safe ride characteristics are achieved by utilisation of independent distribution of drive and brake wheel torques.

Effect of Using Polymers on Bituminous Mixtures Characteristics in Egypt

Attention has been increasing towards the use of polymer modified asphalt, because conventional asphalt mixtures cannot resist the high axle loads and tire pressures. Several classes of modified binders have been used in asphalt pavements. The main objective of this research was to evaluate the effect of adding several types of polymers on asphalt cement and asphalt concrete mixtures. Experimental program involved two phases. The first phase was modifying the asphalt using six types of polymers then evaluating the properties of the modified asphalt. The second phase was evaluating the effect of binder modification on Marshall mix design characteristics and indirect tensile strength of the asphalt concrete mixtures. It was found that the optimum percentage of PVC, plastic bags and novolac was 4%, and the optimum percentage of HDPE was 5% by weight of asphalt. These percentages caused increase in kinematic viscosity, stability, and indirect tensile strength and caused reduction in penetration.

AXL is a key regulator of inherent and chemotherapy-induced invasion and predicts a poor clinical outcome in early-stage colon cancer.

Despite the use of 5-fluorouracil (5-FU)-based adjuvant treatments, a large proportion of patients with high-risk stage II/III colorectal cancer will relapse. Thus, novel therapeutic strategies are needed for early-stage colorectal cancer. Residual micrometastatic disease from the primary tumor is a major cause of patient relapse. To model colorectal cancer tumor cell invasion/metastasis, we have generated invasive (KRASMT/KRASWT/+chr3/p53-null) colorectal cancer cell subpopulations. Receptor tyrosine kinase (RTK) screens were used to identify novel proteins that underpin the migratory/invasive phenotype. Migration/invasion was assessed using the XCELLigence system. Tumors from patients with early-stage colorectal cancer (N = 336) were examined for AXL expression. Invasive colorectal cancer cell subpopulations showed a transition from an epithelial-to-mesenchymal like phenotype with significant increases in migration, invasion, colony-forming ability, and an attenuation of EGF receptor (EGFR)/HER2 autocrine signaling. RTK arrays showed significant increases in AXL levels in all invasive sublines. Importantly, 5-FU treatment resulted in significantly increased migration and invasion, and targeting AXL using pharmacologic inhibition or RNA interference (RNAi) approaches suppressed basal and 5-FU-induced migration and invasion. Significantly, high AXL mRNA and protein expression were found to be associated with poor overall survival in early-stage colorectal cancer tissues. We have identified AXL as a poor prognostic marker and important mediator of cell migration/invasiveness in colorectal cancer. These findings provide support for the further investigation of AXL as a novel prognostic biomarker and therapeutic target in colorectal cancer, in particular in the adjuvant disease in which EGFR/VEGF-targeted therapies have failed.

Axl mediates acquired resistance of head and neck cancer cells to the epidermal growth factor receptor inhibitor erlotinib.

Elevated expression and activity of the epidermal growth factor receptor (EGFR) is associated with development and progression of head and neck cancer (HNC) and a poor prognosis. Clinical trials with EGFR tyrosine kinase inhibitors (e.g., erlotinib) have been disappointing in HNC. To investigate the mechanisms mediating resistance to these agents, we developed an HNC cell line (HN5-ER) with acquired erlotinib resistance. In contrast to parental HN5 HNC cells, HN5-ER cells exhibited an epithelial-mesenchymal (EMT) phenotype with increased migratory potential, reduced E-cadherin and epithelial-associated microRNAs (miRNA), and elevated vimentin expression. Phosphorylated receptor tyrosine kinase profiling identified Axl activation in HN5-ER cells. Growth and migration of HN5-ER cells were blocked with a specific Axl inhibitor, R428, and R428 resensitized HN5-ER cells to erlotinib. Microarray analysis of HN5-ER cells confirmed the EMT phenotype associated with acquired erlotinib resistance, and identified activation of gene expression associated with cell migration and inflammation pathways. Moreover, increased expression and secretion of interleukin (IL)-6 and IL-8 in HN5-ER cells suggested a role for inflammatory cytokine signaling in EMT and erlotinib resistance. Expression of the tumor suppressor miR-34a was reduced in HN5-ER cells and increasing its expression abrogated Axl expression and reversed erlotinib resistance. Finally, analysis of 302 HNC patients revealed that high tumor Axl mRNA expression was associated with poorer survival (HR = 1.66, P = 0.007). In summary, our results identify Axl as a key mediator of acquired erlotinib resistance in HNC and suggest that therapeutic inhibition of Axl by small molecule drugs or specific miRNAs might overcome anti-EGFR therapy resistance.

Continuous application of direct sowing: Traffic effect on subsoil compaction and maize (Zea mays L.) yields in Argentinean Pampas

Our main objective was to evaluate the effect of subsoil compaction on maize (Zea mays L.) yields. This work was performed on clayey soil and on loamy Entic Haplustoll soil. Three types of direct sowing (DS) equipment (heavy load (HL), medium load (ML) and light load (LL)) were utilised. We hypothesised that the application of DS over five continuous years would cause subsoil compaction and that maize yields would be affected. The cone index (CI), root dry matter per plant (RDM), dry matter per plant (DMP) and maize yields (MY) were measured. The results show that after five years, the CI values produced by the HL treatment were higher in clayey soil than in loamy soil, which decreased maize yields. At site 1, the highest average RDM values were found in 2005; the measurements for the LL and ML treatments were 45.9 and 43.1g plant−1, respectively, whereas the highest value in the HL treatment was 35.6g plant−1. For site 2, the highest RDM values were found in 2006; the measurements for the LL and ML treatments were 42.6 and 38.2g plant−1, respectively, whereas the highest value in the HL treatment was 30.2g plant−1. The average DMP measurement (site 1) was 150g plant−1 in the LL treatment, followed by 147g plant−1 in ML and 137g plant−1 in HL. Site 2 values were 143, 137 and 130g plant−1 in LL, ML and HL, respectively. At both sites, the HL treatment resulted in a significantly lower maize yield (14.3% and 11% for sites 1 and 2, respectively) compared to the ML and LL treatments. The main conclusions were as follows: when clayey and loamy soil was trafficked with between loads of 144 and 177.9kN for five years, the cone index was increased in the subsoil. These high CI values caused by the combination of a high axle load and ground pressure would have affected the maize yields.

Downregulation of Axl in non-MYCN amplified neuroblastoma cell lines reduces migration

Neuroblastomas (NBL) are common pediatric solid tumors with a variable clinical course. At diagnosis half of all neuroblastoma patients presents with metastatic disease. The mechanisms of metastasis are largely unknown. Gene expression profiles (HU133plus2.0 arrays, Affymetrix) of 17 NBL and 5 peripheral neuro-ectodermal cell lines were used to identify a subgroup of non-MYCN amplified (non-NMA) NBL cell lines with a distinct gene expression profile and characterized by high expression of AXL. Axl is a tyrosine kinase receptor which plays a role in the metastatic process of several types of cancer. We hypothesized that Axl contributes to the metastasizing potential of non-NMA NBL and tested if AXL silencing diminishes malignant properties of high Axl expressing cell lines.AXL was silenced in two non-NMA NBL cell lines by using a lentiviral shRNA construct that was able to transduce these cell lines with more than 90% infection efficiency. Axl mRNA and protein level were efficiently knocked-down resulting in a decrease of migration of Axl positive cell lines GI-M-EN and SH-EP-2, and decreased invasion of GI-M-EN. Morphologically, Axl knockdown induced more rounded cells with a loss of contact. Intracellularly, we observed induction of stress fibers (immunofluorescence F-actin). These changes in cytoskeleton were associated with decreased migration, but were not accompanied by changes in genes involved in epithelial to mesenchymal transition such as CDH2, VIM or MMP9. No effects were observed for cell proliferation, apoptosis or downstream pathways. In conclusion, AXL is identified as a possible mediator of NBL metastasis.

Higher expression of receptor tyrosine kinase Axl, and differential expression of its ligand, Gas6, predict poor survival in lung adenocarcinoma patients.

BackgroundDownstream activation through receptor tyrosine kinases (RTKs) plays important roles in carcinogenesis. In this study, we assessed the clinical involvement of Axl, an RTK, and its ligand, Gas6, in surgically treated lung adenocarcinoma.Methods Axl and Gas6 mRNA and protein expression levels were quantified using quantitative real-time polymerase chain reaction and immunohistochemistry, respectively, in completely resected lung adenocarcinoma tissues (n = 88) and were evaluated for correlation with clinicopathologic features and patient survival.ResultsHigher expressions of Axl mRNA/protein and Gas6 protein were significantly related to worse clinicopathological features and prognosis (5-year overall survival rates: Axl mRNA low: 72.3 %, high: 49.7 %, P = 0.047; Axl protein low: 77.5 %, high: 38.6 %, P < 0.001; and Gas6 protein low: 70.5 %, high: 48 %, P = 0.042). On the contrary, higher Gas6 mRNA expression was related to better clinicopathological features and prognosis (5-year overall survival rates: Gas6 mRNA low: 59.2 %, high: 81.8 %, P = 0.054). Multivariate analysis suggests that high Axl mRNA expression may be an independent factor for poor patient prognosis (P = 0.04).ConclusionsIn lung adenocarcinoma, Axl and Gas6 expression levels were associated with tumor advancement and patient survival, thus rendering them as reliable biomarkers and potential targets for treatment of lung adenocarcinoma.

Effect of Excess Axle Loads and High Tire Pressures on Flexible Pavement Performance

The main objective of this paper is to evaluate the performance of the flexible pavement under different conditions of axle loads and tire pressure of different vehicles (trucks) in Egypt.. Strains of different pavement sections were calculated using computer program based on linear elastictheory. Moreover, theoretical analysis was achieved by using BISAR computer program to obtain regression equations to simplify determination of load equivalency factor (LEF) as a function of axle loads and tire pressure for single and tandem axle loads. A comparison between the values of calculated LEF and these that adopted by the AASHTO specifications was achieved . From theresults analysis, it could be obtained that , at low to intermediate axle loads, high tire pressure could cause marked increase in LEF. At high axle loads, variation of equivalency factor with tire pressure could be neglected. Moreover, increased subgrade elastic modulus had insignificant influence on LEF