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E O Backlund

Publications and source records attributed to E O Backlund.

62 records · Page 4Linked to original sources
PubMedDate not supplied

Effects of high and low single dose irradiation on glioma spheroid invasion into normal rat brain tissue in vitro.

The effects of radiation on direction on directional migration in monolayer cultures and brain tissue invasion by two glioblastoma cell lines (D-54 MG, D-247 MG) were investigated. The Leksell Gamma Unit was the radiation source and invasion was registered in an in vitro invasion assay developed in our laboratory. As tumor spheroids and brain tissue aggregates were treated simultaneously in cocultures; the effects of radiation on the interaction between the two tissues could be investigated. Tumor spheroids from both cell lines retained their ability to invade and destroy normal brain tissue, even after irradiation with 47.6 Gy. However, while the D-54 MG tumor spheroids showed a dose-dependent reduction of invasion, tumor spheroids from the D-247 MG cell line did not. In addition, radiation produced a dose dependent inhibition of directional migration of cells from D-54 MG spheroids. A similar significant inhibition of directional migration was found in D-247 MG, but it was not dose-dependent. Transmission electron microscopy revealed a loosening of the neuropil in the brain tissue of irradiated cocultures. However, this structural change did not seem to affect the invasiveness of the tumor. In this preliminary study, irradiation could not prevent invasion of two different glioblastoma cell lines into fetal rat brain tissue. Further studies using the same technique may help to understand the influence of ionizing radiation upon the invasion process in gliomas.

Animals↗
PubMedDate not supplied

Stereotactic biopsies as a model for studying the interaction between gliomas and normal brain tissue in vitro.

In order to study tumor invasiveness, the authors used a model system which allows the direct interaction between glioma cells and normal brain tissue to be studied. The spiral needle biopsy technique provides a tissue core with a completely preserved architecture from brain tumors. These biopsies, once cultured, produce three-dimensional multicellular tumor spheroids; they display morphological features similar to those of the original tumor in vivo. As a target fetal rat brain cell aggregates were used, in order to study the invasive process in the microscope. Not surprisingly, different tumors show different patterns of invasion; this variability is not yet clearly correlated with the clinical course of the patient.

Animals↗
PubMedDate not supplied

Radiosurgery in intracranial tumors and vascular malformations.

In 1951 Leksell first coined the term "radiosurgery" indicating a new tool for the neurosurgeon by means of ionizing radiations. The technique consists of cross-firing a stereotactic target with several well-collimated "shots" of radiation. This produces well-defined lesions in the brain without opening the skull. After several significant improvements of this technique, now assisted by a computer, today it is possible to "tailormake" composite radiation fields for any single lesion. Some interesting clinical applications are Cushing's disease, acoustic tumors, pineal region tumors and arteriovenous malformations.

Adenoma↗
PubMedDate not supplied

Colloidal radioisotopes as part of a multi-modality treatment of craniopharyngiomas.

The therapy of craniopharyngiomas has always been a challenge for the neurosurgeon. These tumors often display a cystic or polycystic portion usually bigger than the solid portion. This paper reports therapeutic results in a series of 42 cases; the follow-up range is 10 to 23 yrs. The results are particularly rewarding in the group treated by stereotactic methods exclusively. In any case the optimal management of a craniopharyngioma should include a careful study of the anatomy of the tumor and the intracystic treatment as the first choice if more than 50% of the total tumor bulk is cystic and the number of cysts reasonable.

Colloids↗