Semiquantitative measurements, peak tissue gadolinium concentration (C(peak)), maximum slope of gadolinium increase (slope), and BEZ235 PI3K/Akt/mTOR inhibitor area under the gadolinium curve at 60 seconds (AUC(60)) were also calculated. Perfusion
parameters and tumor size changes were correlated with carbohydrate antigen 19-9 levels. Comparisons between pre- and posttreatment studies were performed by using the Wilcoxon signed rank test, and comparisons between responders and nonresponders were performed by using the Mann-Whitney test.
Results: After therapy, K(trans), v(e), C(peak), slope, and AUC(60) decreased significantly (P = .02, .001, .002, .007, and .01, respectively). Tumor size and K(ep) were not significantly changed. Pretreatment K(trans) and K(ep) were significantly higher (P = .02 and .006, respectively) in tumors that showed marker response than in those that did not. A pretreatment K(trans) value (milliliters of blood per milliliter of tissue times Nepicastat concentration minutes) of more than 0.78 mL/mL . min was 100% sensitive and 71% specific for subsequent tumor response. Semiquantative parameters and tumor size were not different between the groups.
Conclusion: Pretreatment K(trans) measurement in pancreatic tumors can predict response to antiangiogenic
therapy. All perfusion parameters showed substantial reduction after 28 days of combined chemotherapy and antiangiogenic therapy. (C) RSNA, 2010″
“The reactive extrusion of maleic anhydride grafted polypropylene (PP-g-MAH) with ethylenediamine (EDA) as coupling agent is carried out in a corotating twin-screw extruder to produce long chain branched polypropylene (LCBPP). Part of PP-g-MAH is replaced by maleic anhydride grafted
high-density polyethylene (HDPE-g-MAH) or linear low-density polyethylene (LLDPE-g-MAH) to obtain hybrid long chain branched (LCB) polyolefins. Compared with the PP-g-MAH, PE-g-MAH, and their blends, the LCB polyolefins exhibit excellent dynamic shear and transient extensional rheological characteristics such as increased dynamic modulus, higher low-frequency complex viscosity, broader relaxation spectra, significantly enhanced melt strength and strain-hardening behaviors. The LCB polyolefins also have higher tensile strength, tensile modulus, selleck chemicals llc impact strength and lower elongation at break than their blends. Furthermore, supercritical carbon dioxide (scCO(2)) is constructively introduced in the reactive extrusion process. In the presence of scCO(2), the motor current of the twin extruder is decreased and LCB polyolefins with lower melt flow rate (MFR), higher complex viscosity and increased tensile strength and modulus can be obtained. This indicates that the application of scCO(2) can reduce the viscosity of melt in extruder, enhance the diffusion of reactive species, and then facilitate the long chain branching reaction between anhydride group and primary amine group. (C) 2011 Wiley Periodicals, Inc.