Radical stereotactic radiosurgery with real-time tumor motion tracking in the treatment of small peripheral lung tumors

<p>Abstract</p> <p>Background</p> <p>Recent developments in radiotherapeutic technology have resulted in a new approach to treating patients with localized lung cancer. We report preliminary clinical outcomes using stereotactic radiosurgery with real-time tumor motion tracking to treat small peripheral lung tumors.</p> <p>Methods</p> <p>Eligible patients were treated over a 24-month period and followed for a minimum of 6 months. Fiducials (3–5) were placed in or near tumors under CT-guidance. Non-isocentric treatment plans with 5-mm margins were generated. Patients received 45–60 Gy in 3 equal fractions delivered in less than 2 weeks. CT imaging and routine pulmonary function tests were completed at 3, 6, 12, 18, 24 and 30 months.</p> <p>Results</p> <p>Twenty-four consecutive patients were treated, 15 with stage I lung cancer and 9 with single lung metastases. Pneumothorax was a complication of fiducial placement in 7 patients, requiring tube thoracostomy in 4. All patients completed radiation treatment with minimal discomfort, few acute side effects and no procedure-related mortalities. Following treatment transient chest wall discomfort, typically lasting several weeks, developed in 7 of 11 patients with lesions within 5 mm of the pleura. Grade III pneumonitis was seen in 2 patients, one with prior conventional thoracic irradiation and the other treated with concurrent Gefitinib. A small statistically significant decline in the mean % predicted DLCO was observed at 6 and 12 months. All tumors responded to treatment at 3 months and local failure was seen in only 2 single metastases. There have been no regional lymph node recurrences. At a median follow-up of 12 months, the crude survival rate is 83%, with 3 deaths due to co-morbidities and 1 secondary to metastatic disease.</p> <p>Conclusion</p> <p>Radical stereotactic radiosurgery with real-time tumor motion tracking is a promising well-tolerated treatment option for small peripheral lung tumors.</p

Morphologic and metabolic changes in rat osteoblast cultures during the dark reaction with 8-methoxypsoralen

The dark reaction of 8-methoxypsoralen (8-MOP) with cultured rat osteoblasts did not cause significant changes in cellular replication rates or in the synthesis RNA and proteins. Microscopic examination, however, revealed that the dark reaction resulted in massive accumulation of perinuclear lipids and in the statistically significant enhancement of alkaline phosphatase activity. A sharp, and statistically significant, upsurge of lipid synthesis in osteoblasts preceded microscopically detectable accumulation of lipids and occurred only during the initial, but not during the subsequent stages of the dark reaction. These results suggest that in the course of the dark reaction the plasma membrane of osteoblasts is a target of psoralen

Interaction of cultured rat osteoblasts with 8-methoxypsoralen during irradiation with long-wave ultraviolet light

Rat osteoblasts in monolayer cell cultures have been irradiated with long-wave ultraviolet light (UVA) in the presence and without 8-methoxypsoralen (8-MOP). In the absence of 8-MOP, the exposures to UVA (3 x 10(-3)W.cm-2) for up to 30 min have not affected cellular viability, the rate of 14C-acetate incorporation, and alkaline phosphatase (AP) activity. However, it depressed 3H-TdR incorporation rates by osteoblasts. In the presence of 15 to 100ng of 8-MOP/ml, even 5-min irradiation of osteoblasts was sufficient to reduce DNA synthesis. Much higher (0.5 to 1.0 micrograms/ml) 8-MOP concentrations were required to depress lipid synthesis, AP activity, and the viability of irradiated cells. These results suggest that in osteoblasts the machinery of DNA synthesis is especially labile to photosensitization with 8-MOP and UVA, whereas UVA light by itself exerts a less potent inhibitory effect

ECCM15 -15 PREPARATION AND CHARACTERIZATION OF POLY(ETHYLENE OXIDE)/LITHIUM MONTMORILLONITE COMPOSITES

Abstract Poly(ethylene oxide)/lithium montmorillonite (PEO/LiMMT) composites were prepared by mixing and ultrasonication PEO and LiMMT in water. Characterization of PEO/LiMMT composites was performed by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR) and non-isothermal thermogravimetry (TGA). DSC and TGA reveal that higher loadings of LiMMT significantly influence the crystallinity, melting temperatures and thermal stability of PEO, respectively. Glass transition temperatures of PEO do not change with addition of LiMMT. FT-IR analysis shows that the helical structure of PEO chains is distorted in PEO/LiMMT composites. Changes of activation energy in composites compared to pure PEO indicate possible changes in the mechanism of the nonisothermal degradation of PEO due to addition of LiMMT. Introduction Poly(ethylene oxide) (PEO) as solid polymer electrolyte in lithium polymer batteries has many advantages over its liquid counterparts or organic solutions due to the ease of processing, stable electrochemical characteristics and excellent mechanical propertie