| 1. |
- Martens, L., et al.
(författare)
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Electromagnetic field calculations used for exposure experiments on small animals in TEM-cells
- 1993
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Ingår i: Bioelectrochemistry and Bioenergetics. - : Elsevier BV. - 0302-4598. ; 30:C, s. 73-81
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Tidskriftsartikel (refereegranskat)abstract
- Three-dimensional electromagnetic calculations for loaded transverse electromagnetic (TEM) transmission cells are presented. Based on those calculations a prediction of the perturbation of the standard uniform field in the TEM-cell, due to the scattering by inhomogeneous structures placed inside the cell cavity, is given. The influence of the dimensions of a lossy structure and its position in the TEM-cell on its absorption of the electromagnetic fields is presented. Knowing the perturbation of the uniform field is important for good interpretation of the biological experimental results.
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| 2. |
- Andersson-Engels, Stefan, et al.
(författare)
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Clinical recording of laser-induced fluorescence spectra for evaluation of tumour demarcation feasibility in selected clinical specialities
- 1991
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Ingår i: Lasers in Medical Science. - 0268-8921. ; 6:4, s. 415-424
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Tidskriftsartikel (refereegranskat)abstract
- Laser-induced autofluorescence spectra from humans were recorded in vivo at three different clinics in a study aimed at investigating the capability of this method to discriminate between malignant tumours and normal surrounding tissues. For the recordings a mobile trolley with the necessary equipment was constructed for use in an examination room or in an operating theatre environment. Laser light was guided through a 600m optical fibre to the target tissue. The fluorescence from the excited tissue was collected with the same fibre and was fed to an optical multichannel analyser. Two excitation wavelengths were used (337 and 405 nm) in order to optimize the fluorescence signals in two interesting wavelength regions (380–500 and 550–700 nm). Oral and oropharyngeal tumours excited with 405 nm light contained detectable endogenous porphyrins and were in this way discriminated from the normal mucosa. Astrocytoma grade III–IV fluorescence different from that of normal brain tissue, while tumours in the bronchial tree were not detectable using the spectral shape of the pure tissue autofluorescence.
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| 3. |
- Andersson-Engels, Stefan, et al.
(författare)
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Identification of brain tumours in rats using laser-induced fluorescence and haematoporphyrin derivative
- 1989
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Ingår i: Lasers in Medical Science. - 0268-8921. ; 4:4, s. 241-249
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Tidskriftsartikel (refereegranskat)abstract
- Laser-induced fluorescence has been used for the identification of brain tumours in rats, which have been previously given tumour-seeking haematoporphyrin derivative. A pulsed nitrogen laser (λ=337 nm) was used in conjunction with an optical multichannel analyzer. For both inoculated RG-2 and TCVC rat-brain-tumour models, the blue autofluorescence was strongly reduced in the tumour compared with normal brain tissue, and at the same time the characteristic red-drug signal increased. The contrast between tumour and normal tissue was strongly enhanced by forming the ratio between the two signals. Implications for possible improvement of tumour delineation in brain tumour surgery are discussed.
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| 4. |
- Andersson-Engels, S., et al.
(författare)
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Tissue diagnostics using laser-induced fluorescence
- 1989
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Ingår i: Berichte der Bunsengesellschaft für Physikalische Chemie. - : Wiley. - 0005-9021. ; 93:3, s. 335-342
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Tidskriftsartikel (refereegranskat)abstract
- We have performed extensive investigations of laser-induced fluorescence in animal and human tissue aimed at instant tissue characterization. Autofluorescence, as well as specific fluorescence from HPD/DHE and other photosensitizers, has been utilized. The studies have been focused on the demarcation of malignant tumours and atheroscleortic plaques. A nitrogen laser or an excimer-pumped dye laser was used to induce fluorescence, which was analysed with an intensified optical multichannel system. A fibre-optic sensor system was developed for the clinical work. Multi-colour fluorescence imaging has also been demonstrated along a line and equipment for two-dimensional imaging is being constructed. Dimensionless spectroscopic functions, which are not affected by factors that are clinically uncontrollable have been employed for optimum tissue discrimination. The investigations have so far been performed in a time-integrated mode, but time-resolved studies are now being initiated to fully exploit the diagnostic power of tissue laser-induced fluorescence. In addition to a presentation of our own work a brief review of tissue fluorescence studies performed by other groups is also given.
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| 5. |
- Capala, J, et al.
(författare)
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Boron neutron capture therapy for glioblastoma multiforme : Clinical studies in Sweden
- 2003
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Ingår i: Journal of Neuro-Oncology. - 1573-7373. ; 62:1, s. 135-144
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Tidskriftsartikel (refereegranskat)abstract
- A boron neutron capture therapy (BNCT) facility has been constructed at Studsvik, Sweden. It includes two filter/moderator configurations. One of the resulting neutron beams has been optimized for clinical irradiations with a filter/moderator system that allows easy variation of the neutron spectrum from the thermal to the epithermal energy range. The other beam has been designed to produce a large uniform field of thermal neutrons for radio-biological research. Scientific operations of the Studsvik BNCT project are overseen by the Scientific Advisory Board comprised of representatives of major universities in Sweden. Furthermore, special task groups for clinical and preclinical studies have been formed to facilitate collaboration with academia. The clinical Phase II trials for glioblastoma are sponsored by the Swedish National Neuro-Oncology Group and, presently, involve a protocol for BNCT treatment of glioblastoma patients who have not received any therapy other than surgery. In this protocol, p-boronophenylalanine (BPA), administered as a 6-h intravenous infusion, is used as the boron delivery agent. As of January 2002, 17 patients were treated. The 6-h infusion of 900 mg BPA/kg body weight was shown to be safe and resulted in the average blood-boron concentration of 24 μg/g (range: 15-32 μg/g) at the time of irradiation (approximately 2-3 h post-infusion). Peak and average weighted radiation doses to the brain were in the ranges of 8.0-15.5 Gy(W) and 3.3-6.1 Gy(W), respectively. So far, no severe BNCT-related acute toxicities have been observed. Due to the short follow-up time, it is too early to evaluate the efficacy of these studies.
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| 6. |
- Ceberg, Crister, et al.
(författare)
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Enhanced boron uptake in RG 2 rat gliomas by electropermeabilization in vivo--a new possibility in boron neutron capture therapy
- 1994
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Ingår i: Anti-Cancer Drugs. - 0959-4973. ; 5:4, s. 463-466
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Tidskriftsartikel (refereegranskat)abstract
- Accumulation of boron in tumor tissue is an indispensable requirement for boron neutron capture therapy and it is important that the uptake is as high as possible. In this work we have studied the influence of electropermeabilization in vivo on the uptake of boron in normal and RG 2 glioma bearing Fischer 344 rats. Two different boron compounds, a sulfhydryl boron hydride (BSH) and a boronated porphyrin (BOPP), have been investigated. The rats were infused intravenously during 5 min with 175 micrograms BSH/g body weight or 12 micrograms BOPP/g body weight. Two electrodes were placed 5 mm apart in the brain and electropermeabilization was performed with eight square 400 V pulses at 4 and 7 min after the end of the infusion. After 6 h the animals were killed, and the boron content in the tumors and the surrounding brain was measured with neutron-activated autoradiography. In electropermeabilized healthy animals the BOPP uptake was low and limited to the electrode lesions, whereas BSH was spread extensively throughout the hemisphere. Rats with gliomas showed doubled (BOPP) to 10-fold (BSH) uptake of boron in the tumor when electropermeabilization was performed as compared with untreated animals. We conclude that electropermeabilization in the future may provide an interesting possibility to increase the uptake of certain boron compounds before neutron capture therapy.
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| 7. |
- Lonn, Stefan, et al.
(författare)
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Long-term mobile phone use and brain tumor risk
- 2005
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Ingår i: American Journal of Epidemiology. - : Oxford University Press (OUP). - 0002-9262 .- 1476-6256. ; 161:6, s. 526-535
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Tidskriftsartikel (refereegranskat)abstract
- Handheld mobile phones were introduced in Sweden during the late 1980s. The purpose of this population-based, case-control study was to test the hypothesis that long-term mobile phone use increases the risk of brain tumors. The authors identified all cases aged 20-69 years who were diagnosed with glioma or meningioma during 2000-2002 in certain parts of Sweden. Randomly selected controls were stratified on age, gender, and residential area. Detailed information about mobile phone use was collected from 371 (74%) glioma and 273 (85%) meningioma cases and 674 (71%) controls. For regular mobile phone use, the odds ratio was 0.8 (95% confidence interval: 0.6, 1.0) for glioma and 0.7 (95% confidence interval: 0.5, 0.9) for meningioma. Similar results were found for more than 10 years' duration of mobile phone use. No risk increase was found for ipsilateral phone use for tumors located in the temporal and parietal lobes. Furthermore, the odds ratio did not increase, regardless of tumor histology, type of phone, and amount of use. This study includes a large number of long-term mobile phone users, and the authors conclude that the data do not support the hypothesis that mobile phone use is related to an increased risk of glioma or meningioma.
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| 8. |
- Andersson, P. S., et al.
(författare)
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TISSUE CHARACTERIZATION USING LASER-INDUCED FLUORESCENCE.
- 1987
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Ingår i: Conference on Lasers and Electro-Optics. - 0936659491 ; 14, s. 46-48
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Konferensbidrag (refereegranskat)abstract
- In cancer tumor detection, tissue autofluorescence and characteristic features of injected hematoporphyrin derivative (HPD) can be utilized. The authors have studied the importance of the excitation wavelength for the achievable contrast between tumor and surrounding tissue using a rat tumor model. They have also compared the relative merits of two HPD preparations for tumor fluorescence detection. The real-time capability of the fluorescence technique is discussed.
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| 9. |
- Engstrom, P.E., et al.
(författare)
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Electrically mediated drug delivery for treatment of an adenocarcinoma transplanted into rat liver
- 2001
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Ingår i: Anticancer research. - 1791-7530. ; 21:3B, s. 1817-1822
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: In this study, electrochemotherapy (ECT), i.e. tumour treatment based on local augmentation of intracellular drug delivery from short, intense electric pulses, was evaluated in rats with an adenocarcinoma implanted into the liver. Tumour response and concentrations of macrophages and T-lymphocytes (CD4 and CD8) in and around the tumour were measured.MATERIALS AND METHODS: Rats were treated with permeabilizing electric pulses, bleomycin, or both, eight days after implantation of the tumour, while one group received sham treatment.RESULTS: Treatment with electric pulses and bleomycin resulted in a significantly reduced lesion volume and 92% cure rate (12 out of 13, p<0.0002 compared to the other treatment groups). The highest concentration of CD8 lymphocytes was found in tumours treated with electric pulses and bleomycin. Macrophages were found mainly in tumours treated with electric pulses, with or without bleomycin.CONCLUSION: Electrochemotherapy using millisecond exponential pulses and bleomycin is efficient in a rat liver tumour model and appears to stimulate the host's immune system.
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| 10. |
- Engström, P, et al.
(författare)
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Distribution of bleomycin in a rat model
- 2000
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Ingår i: Electrochemotherapy, Electrogenetherapy, and Transdermal Drug Delivery : Electrically Mediated Delivery of Molecules to Cells - Electrically Mediated Delivery of Molecules to Cells. - New Jersey : Humana Press. - 9780896036062 - 9781592590803 ; 37, s. 92-285
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Bokkapitel (refereegranskat)abstract
- Bleomycin has, in the years of developing electrochemotherapy (ECT), proven to be an extremely potent drug for this cancer treatment modality and is also the most frequently applied chemical agent. It is of importance to investigate the pharmacokinetics of bleomycin under normal conditions and particularly in combination with ECT.
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