Targeting of small molecule anticancer drugs to the tumour and its vasculature using cationic liposomes: lessons from gene therapy

Cationic (positively charged) liposomes have been tested in various gene therapy clinical trials for neoplastic and other diseases. They have demonstrated selectivity for tumour vascular endothelial cells raising hopes for both antiangiogenic and antivascular therapies. They are also capable of being selectively delivered to the lungs and liver when administered intravenously. These vesicles are being targeted to the tumour in various parts of the body by using advanced liposomal systems such as ligand-receptor and antibody-antigen combinations. At present, the transferrin receptor is commonly used for cancer-targeted drug delivery systems including cationic liposomes. This review looks at the growing utility of these vesicles for delivery of small molecule anticancer drugs

Effect of Specimen Length on Longitudinal Gas Permeability in Hardwoods

A study was carried out to determine whether the longitudinal gas permeability of hardwoods is affected by specimen length. The results indicate that in most woods tested, the permeability remains constant as length is reduced, except for lengths below 0.75 inch. Thereafter, with decreasing specimen length, permeability increases drastically. The large differences in permeability of samples of different length are attributed to random blockages in the capillary structure of the wood

Effect of Cultural Treatment and Wood-type On Some Physical Properties of Longleaf and Slash Pine Wood

Wood was studied from relatively mature longleaf and slash pine trees that had been growing under experimental treatments including cultivation, two levels of thinning, and four levels of fertilization in various combinations. From discs taken at five heights and separated into three wood-types, green moisture content, radial shrinkage, tangential shrinkage, volumetric shrinkage, latewood percentage, number of rings per inch, and specific gravity were determined. In longleaf pine, there were indications of treatment effect on latewood percentage and the number of rings per inch, with the more intensive treatments generally leading to fewer rings and higher amounts of latewood. In slash pine, a similar trend was found with these two variables. The species exhibited an almost identical trend in the interrelationships among properties. Green moisture content was negatively correlated with specific gravity and moisture content of the innerwood and middlewood increased with height. Shrinkage was found to be negatively correlated with height and positively correlated with specific gravity, except in the innerwood. Latewood percentage accounted for much of the variation in specific gravity in all wood-types. In the outerwood only, there was a positive but weak correlation of number of rings with specific gravity

Research: Is resection of tumours involving the pelvic ring justified? : A review of 49 consecutive cases

INTRODUCTION: Pelvic surgery is challenging and impacts significantly on limb and visceral function, thus, raising the question "is heroic surgery justifiable". This study assessed the functional, oncologic and surgical outcomes following pelvis tumour resections. METHODS: Between 1996–2003, 49 patients (mean age 43 years) underwent pelvic tumour resections- 38 primary malignant tumours, 5 secondary tumours and 6 benign tumours. Bone tumours comprised 5 osteosarcomas, 5 Ewings sarcomas, and 12 chondrosarcomas. Of the soft tumours, 9 were of neural origin. Tumours involved the ilium, acetabulum, pubic bones, sacrum or a combination of these. Functional assessment was performed and no patient had metastases at presentation. RESULTS: There were 41 limb sparing resections and 8 hindquarter amputations. Surgical margins were intralesional (1), marginal (13), wide (26), and radical (3). Of limb sparing surgery, prosthetic reconstructions were performed in 10 patients, biologic reconstructions in 6, a combination of these in 3 and no reconstruction in others. There was 1 intraoperative death, 7 local recurrences and 19 metastases. Death from disease occurred at a mean of 14.2 months with a mean followup of 27 (1–96) months. Amputation and periacetabular resections had worse functional outcomes. Emotional acceptance was surprisingly high. CONCLUSION: Pelvic resections are complex. Functional outcome is significantly affected by surgery. Disease control is similar to limb tumours. Emotional acceptance of surgery in survivors was surprisingly high. Major pelvic resection for malignancy appears justified

Post-radiation sarcoma of the neck treated with re-irradiation followed by wide excision

BACKGROUND: Post-radiation sarcoma (PRS) is an uncommon disease manifesting as sarcoma in a previously irradiated field, usually with a latent period of 5 years or more. Literature is limited to small series. Optimal management of this disease is unclear. Positive margins are common following attempted curative surgery and outcomes are poor. Radiotherapy is hardly used and its effect on PRS is not known. We described a case of PRS treated with preoperative radiotherapy followed by margin-negative wide excision. CASE PRESENTATION: The 59-year-old patient presented with a mass in the left supraclavicular fossa and numbness in the arm, six years following radical irradiation of the head and neck for nasopharyngeal carcinoma. Open biopsy showed pleomorphic spindle cell sarcoma. She was treated with pre-operative hyperfractionated radiotherapy followed by margin-negative wide excision and nerve grafting. Cumulative radiation dose to the supraclavicular fossa was 98 Gy. Histological examination of the post-irradiation tumor specimens showed evidence of significant tumor response to re-irradiation. The patient remained free of disease five years after surgery with excellent functional outcome. CONCLUSION: Role of radiotherapy in PRS is uncertain. We described a case that was successfully managed with preoperative radiotherapy and margin-negative wide excision in terms of tumor control and functional outcomes. The impact of radiotherapy was demonstrated in the post-irradiation resected specimen. Further investigation using re-irradiation and surgery in PRS is warranted

Variation in Shrinkage Properties of Second-Growth Baldcypress and Tupelo-Gum

Trees of baldcypress and tupelo-gum aged from 55 to 75 years, growing in a naturally regenerated stand in the Atchafalaya Basin in south Louisiana, were felled to provide samples for determination of shrinkage, specific gravity, and extractive content. Samples were taken from six heights and from three radial positions (=wood-types) along three radii. Differences among trees and among plots (which had different basal areas) were found for all measured variables. There were also variations in unextracted specific gravity with height in the tree and wood-type in baldcypress, and, except for specific gravity, with wood-type in tupelo-gum. After extraction, shrinkage effects of height and wood-type were reduced or disappeared. Specific gravity was generally lowest in the lower portion of the stem and in the outerwood. Correlation of shrinkage with specific gravity was highest in the outerwood, and extractive content was correlated with shrinkage in tupelo-gum but not in baldcypress