Polymyxin B [HRP]

Objective: To explore the correlation between dual source computed tomography perfusion imaging (CTPI) and microvascular parameters, and evaluate the value of CTPI in the differential diagnosis of solitary pulmonary nodule (SPN). Methods: 65 consecutive patients with SPN who successfully underwent pre-operative CT perfusion imaging with dual source CT and received a final diagnosis by postoperative pathology. The cases were divided into malignant, benign and inflammatory groups according to the pathological results. CT perfusion parameters, such as blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface (PMB) were obtained by performing CTPI of SPNs. The postoperative specimens of SPNs were immunohistochemically stained for CD34 and SMA to detect microvessel density (MVD) and luminal vascular parameters, such as luminal vascular number (LVN), lumina] vascular area (LVA) and lumina] vascular perimeter (LVP). The receiver operating characteristic (ROC) curve was used to assess the diagnostic efficiency of CT perfusion parameter in diagnosing malignant SPNs. Results: In these 65 cases, malignant, benign and inflammatory SPNs were respectively 39, 14 and 12 cases. Significant difference was observed in LVN/MVD, LVA and LVP among the three groups (P < 0.05). The correlation between CT perfusion parameters (BF, BV and PMB) and the lumina] vascular parameters was stronger than that with MVD (P < 0.05). PMB has the strongest correlation with LVN/MVD. Using BF 60m1/100m1/ min, BV 6.34m1/100m1 and PMB 13.35m1/100 ml/min for the diagnosis, the area under the curve (AUC) of the ROC curve was 0.760, the sensitivity was 82% and the specificity was 61%. Conclusions: The main indicators reflecting blood perfusion of SPN are the degree of lumen or maturity of microvessels (LVN, LVA and LVP), not just the number of microvessels (e.g. MVD). CT perfusion imaging can be used as an important method to non-invasively evaluate tumour angiogenesis and help to distinguish malignant SPNs from benign and inflammatory SPNs.

This article presents an investigation of 6 different triblock SBS (styrene-butadien-styrene) polymers with different structure (radial and linear) and different butadien:styrene ratio, used for modifying bitumen (70/100) with 5 and 16% polymer content. The behaviour of the polymer and the polymer modified bitumen (PmB) is characterized by dynamical shear rheometer (DSR), differential scanning calorimetry (DSC) and fluorescence microscopy (FM). The conditions for the formation of a polymer network within PmB and its effect on the mechanical performance of PmB were investigated. Based on the obtained results the number of styrene end blocks was identified as the key parameter for the formation of a polymer network. The polystyrene content controlled the coalescence and hence the distribution of polymer within the PmB. An increased poly butadiene content, on the other hand, lead to a more pronounced swelling of polymer within PmB by the adsorption of the maltene phase from bitumen, resulting in an increase of the polybutadiene particle size.