1,229 research outputs found

    Clinical results of quality-assured hyperthermia: Chemotherapy and hyperthermia.

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    Local and regional hyperthermia as part of multimodality treatment approaches was proven to enhance the therapeutic efficacy of standard radiotherapy and chemotherapy protocols in the treatment of several malignant diseases. Recent technical advances, e.g. CT- or MRI-based planning systems, are contributing to improved quality assurance. This book gives an overview on biological and technical fundamentals, hyperthermia procedures and clinical indications, and summarizes clinical results for the combined use of hyperthermia with radio- and/or chemotherapy. It is dedicated to the interested reader without any expertise in local and regional hyperthermia and provides fast access for the use of hyperthermia

    Current and future clinical trials.

    No full text
    Local and regional hyperthermia as part of multimodality treatment approaches was proven to enhance the therapeutic efficacy of standard radiotherapy and chemotherapy protocols in the treatment of several malignant diseases. Recent technical advances, e.g. CT- or MRI-based planning systems, are contributing to improved quality assurance. This book gives an overview on biological and technical fundamentals, hyperthermia procedures and clinical indications, and summarizes clinical results for the combined use of hyperthermia with radio- and/or chemotherapy. It is dedicated to the interested reader without any expertise in local and regional hyperthermia and provides fast access for the use of hyperthermia

    Hyperthermia combined with chemotherapy - Biological rationale, clinical application, and treatment results

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    There is substantial evidence from preclinical data that the antitumor cytotoxicity of selected chemotherapeutic agents either alone or combined with radiation can be enhanced by appropriate heat exposure (40-44 degrees C) of cells or tumor tissues. Based upon these results the integration of hyperthermia as an additional treatment modality, given simultaneously with systemic chemotherapy or in combination with radiochemotherapy, is currently tested at the clinic. Regional hyperthermia combined with chemotherapy or radiochemotherapy showed impressive results (phase II studies) at clinical relevant temperatures in locally advanced tumors of different entities in terms of objective response rate, local tumor control and relapse-free survival. Clinical protocols of well-designed phase III trials on combined treatment modalities integrating hyperthermia are rather limited but for some tumors confirm its clinical benefit. In general, the clinical approach to use hyperthermia has gained much more interest within in the field of medical oncology. One of the major reason is the substantial technical improvements made with the available commercial equipment for local or regional heating, especially in case of deep-seated lesions or systemic heating. Further testing of the potential of hyperthermia combined with chemotherapy or radiochemotherapy in prospective randomized trials are warranted. At this time, hyperthermia as an adjunct to conventional treatment strategies is recommended in the setting of clinical protocols. The results of prospective trials should answer the question for which types of local advanced or metastatic tumors hyperthermia becomes standard as part of a multi-modal treatment strategy

    Ifosfamide with regional hyperthermia in soft-tissue sarcomas

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    For high-risk soft tissue sarcomas (HR-STS) of adults, new treatment strategies are needed to improve outcome with regard to local control and overall survival. Therefore, systemic chemotherapy has been integrated either after (adjuvant) or before (neoadjuvant) optimal local treatment by surgery and radiotherapy in HR-STS. The combination with regional hyperthermia as a new treatment strategy seems to open a new therapeutic window. Copyright (C) 2003 S. Karger AG, Basel

    Feasibility and morbidity of combined hyperthermia and radiochemotherapy in recurrent rectal cancer - Preliminary results

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    Background: The local recurrence rate of colorectal cancer has been significantly reduced due to the use of combined radiochemotherapy. Despite this improvement regarding locally advanced tumour recurrences, the treatment strategy for pre-treated patients remains difficult and unresolved. Patients and Methods: We analysed treatment and follow-up data of 14 patients with local recurrence of rectal cancer who were treated with radiation therapy (RT), chemotherapy (CT) and regional hyperthermia (RHT) from November 1997 to December 2001. Nine of these patients had received irradiation and CT (=pre-treated patients) in the past. For this group, 30.6-39.6 Gy RT, 5-fluorouracil (5-FU) as a continuous infusion over 5 days per week (350 mg/m(2)/24 h) combined with RHT twice a week was given. The 5 remaining patients (=not pre-treated) received conformal irradiation of 45 Gy with a boost between 9 and 14.4 Gy, combined with continuous infusion of 5-FU on days 1-4, and 29-33 (500 mg/m(2)/24 h), and RHT twice a week. Response to therapy was evaluated by means of computed tomography (CT) or magnetic resonance imaging (MRI) and by clinical follow-up. Results: Among 13 evaluated cases, the overall objective response rate was 54% (5 complete responses, 2 partial responses). At mean follow-up of 13.9 months (range 5-32 months) 7 patients were alive. Conclusion: The therapeutic regimen appears to be active in the treatment of local recurrences of rectal cancer. Larger-scaled studies are needed to evaluate the potency of hyperthermia in this therapeutic strategy

    Promotion of cystine uptake, increase of glutathione biosynthesis, and modulation of glutathione status by <em>S</em>-2-(3-aminopropylamino)ethyl phosphorothioic acid (WR-2721) in Chinese hamster cells.

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    We recently found that exposure of cells to different aminothiols promotes cystine uptake and leads to an increase of cellular glutathione by new biosynthesis (Issels et al., Biochem. Pharmacol. 37: 881-888, 1988). Therefore, we further investigated whether the known radioprotective and chemoprotective aminothiol derivative S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) or its dephosphorylated form (WR-1065) will lead to similar effects. In order to convert WR-2721 to the free thiol compound (WR-1065) in vitro, the medium also contained 20 U/ml alkaline phosphatase (AP). For uptake studies a modified McCoy&#39;s 5A medium supplemented with 0.1 mM [35S]cystine was used. In Chinese hamster ovary (CHO) and Chinese hamster ovarian carcinoma (OvCa) cells, WR-2721 exposure alone did not increase the cystine uptake relative to that of control (untreated) cells, while WR-2721 + AP enhanced the uptake of cystine more than twofold in both cell lines. The increase of cystine uptake was dependent on the time of exposure (0-60 min) and the concentrations of WR-2721 (0-8 mM) + AP. Half-maximal uptake of cystine was observed at concentrations of 0.69 and 0.57 mM WR-2721 in CHO and OvCa cells, respectively. Determination of both reduced (GSH) and oxidized (GSSG) cellular glutathione levels after the exposure (0-300 min) to WR-2721 + AP in CHO cells showed a depletion of GSH to less than 10% of the pretreatment value and a 4-fold reduction of the GSH/GSSG ratio. In contrast, in OvCa cells the amount of total glutathione rather increased with no significant change of the GSH/GSSG ratio by the exposure to WR-2721 + AP. Further analysis using high-performance liquid chromatography of cell extracts revealed that the relative amount of incorporated [35S]cystine into glutathione was increased similarly in both cell lines. The data show that precursor availability and new biosynthesis of glutathione is enhanced by the exposure to WR-2721 + AP in vitro despite the differential modulation of the cellular glutathione status in the two cell lines. These findings may have important implications for the use of aminothiols like WR-2721 in various cells and tissues in regard of their response to chemotherapeutic agents, ionizing radiation and/or hyperthermia

    Solution of the problem of composite charge using R.D.38

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    In this paper the author has solved the problem of internal ballistics of composite charge using 'R.D.38' method which is based upon the usual isothermal approximation. A linear law of burning has been assumed

    Author index

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    The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.This is a continuation of the "Author and Subject Index to the Onderstepoort Journal of Veterinary Science and Animal Industry (1933- l950)" and the "Onderstepoort Journal of Veterinary Research (1951 - 1968)" which appeared in June 1969 and covers the period 1969 to 1973, i.e. Volumes 36 to 40. As from 1974 (Volume 41) it is intended to furnish an Author and Subject Index in Number 4 of each volume covering all four numbers for that particular year

    Noise due to unsteady flow past trailing edges

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    This paper presents two-dimensional direct numerical simulations (DNS) of noise generated at trailing edges (TE) with zero thickness. The simulations are conducted specifying either no-slip or slip walls in order to investigate viscous effects. In both cases, small amplitude disturbances are introduced close to the inflow boundary that serve as pressure disturbances at the TE. DNS data reveals that the unsteady Kutta condition is not satisfied, irrespective of the wall boundary condition. However, it appears that the validity of the unsteady Kutta condition is not essential for making an accurate prediction of the far field noise. The far field pressure is predicted as a function of the surface pressure difference using a 2-D modification of Amiet's classical theory, and compared with the far field pressure computed directly. Directivity plots provide evidence that the presence of boundary layers and noise generated by an unsteady wake in the no-slip cases lead to smearing of individual lobes, and that the downstream pointing lobes in no-slip wall cases are probably due to nonlinear noise generation in the wake. The simulations are conducted using a high-order accurate numerical method which is free of upwinding, artificial dissipation or any form of explicit filtering, and employs a novel boundary treatment
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