Search results for "induced"
showing 10 items of 1287 documents
Microwave-induced thermoablation with Amica-probe is a safe and reproducible method to treat solid renal masses: results from a phase I study.
2012
Microwave thermal ablation (MWTA) could be considered in the future for treating small solid renal masses. The aim of the present study was to determine both the tolerability of the new Amica-probe applicator-induced MWTA used in vivo on patients with solid renal masses and the effects of heating on renal tumors and normal renal parenchyma. Fourteen patients with renal masses eligible for open radical nephrectomy were enrolled in this phase I study. All patients underwent MWTA of renal masses during the open surgery procedure before clamping of renal vascular pedicle. The effects of MWTA on patients' coagulation and tumor/renal vasculature were investigated. The histological effects of MWTA…
LOCAL MICROWAVE HYPERTHERMIA AND INTRAVESICAL CHEMOTHERAPY AS BLADDER SPARING TREATMENT FOR SELECT MULTIFOCAL AND UNRESECTABLE SUPERFICIAL BLADDER TU…
1998
Purpose: The role of a combined regimen of local hyperthermia and topical chemotherapy in patients with multifocal and recurrent superficial bladder tumors not curable by transurethral resection was evaluated in a neodjuvant organ sparing clinical study. Materials and Methods: A total of 19 patients with multifocal, superficial grades 1 to 3 bladder tumors that recurred after intravesical chemoprophylaxis or immunoprophylaxis underwent local combined administration of microwave induced hyperthermia and intravesical chemotherapy as a debulking approach. Due to extensive superficial involvement of the bladder walls complete transurethral resection of all tumors seemed technically unfeasible i…
Effects of tumor necrosis factor-alpha on tumor blood flow and hyperthermic treatment.
1989
The impact of recombinant human tumor necrosis factor-alpha (rhTNF-alpha), given alone or in combination with local hyperthermia, on perfusion and growth of a moderately rhTNF-alpha-sensitive rat tumor (DS-carcinosarcoma) was investigated. DS-carcinosarcomas were implanted into the hind foot dorsum of Sprague-Dawley rats. Tumor blood flow (TBF) was measured with the krypton-85 clearance technique. Treatment with either tumor necrosis factor-alpha (0.1-1.0 mg/kg) or hyperthermia (43.3 and 44.3 degrees C, 40 min) can decrease the perfusion of malignant tumors. The TBF reduction was fully established 2 h after rhTNF-alpha injection and lasted for at least 4 h. The application of local hyperthe…
Tumor tissue oxygenation as evaluated by computerized-po2-histography
1990
A computerized pO2 measurement system with a novel electrode motion pattern (Sigma-pO2-histography) was evaluated in vitro and in vivo. The system was found to be reliable in 0.9% saline and 10% hydroxyethylene starch solution and in fresh donor blood. Marked deviations were found in lipid and hemoglobin solutions and in fluorocarbon emulsions. Histograms obtained in rat liver, mouse muscle, and subcutis were similar to previously reported distributions. Direct comparison between Sigma-Eppendorf and self-constructed Whalen-type electrodes in hypoxic tumors gave similar results. A large series of measurements indicated that hypoxic and anoxic tissue areas were frequently found both in isogra…
Hyperlactacidaemia in isolated hyperthermic perfusion of tumour bearing rat limbs: a study of feasibility using a novel infusion solution.
1999
In a methodological study the applicability of hyperlactacidaemia in isolated hyperthermic perfusion of tumour-bearing rat limbs was investigated.In 50 Sprague Dawley rats, DS-sarcoma growth was initiated on the right food dorsum by subcutaneous injection of 0.5 ml ascites cells. In the anaesthetized animals isolated limb perfusion was performed under steady state conditions for 60min using a miniature equipment. Thereafter tumour volume was measured daily. (a) Investigation of feasability: 40 rats were allocated to four groups. Group I: Normothermic perfusion at 38 degrees C, n = 10; Group II: Hyperthermic perfusion at 40-41 degrees C, n = 10; Group III: Normothermic perfusion at 38 degree…
Experimental evidence for a hyperthermia-induced breakdown of tumor blood flow during normoglycemia
1983
A compilation of experimental data is presented indicating that hyperthermia alone can achieve a significant inhibition of tumor blood flow if appropriate heat exposure times and tissue hyperthermia levels are chosen.
Tumour-growth inhibition by induced hyperglycaemia/hyperlactacidaemia and localized hyperthermia.
1996
The present study was undertaken to exploit pathophysiological properties of solid tumours for a tumour-specific therapy. Experiments were carried out on DS-sarcomas implanted s.c. in the hind foot dorsum of Sprague Dawley rats. Treatment strategies included tumour acidification, lactate accumulation and disturbance of the microcirculation by induced systemic hyperglycaemia/hyperlact-acidaemia (15-25/10 mmol/L; for 60 min) as well as localized hyperthermia (water-bath; 43 degrees C, 30 min.). A special infusion solution was developed for the systemic treatment containing glucose, lactic acid and organic buffer without inorganic ions. Growth kinetics of tumour volume and animal survival were…
Laser Doppler flowmetry in subepidermal tumours and in normal skin of rats during localized ultrasound hyperthermia.
1988
Laser Doppler flowmetry has been applied to normal skin and to subepidermal tumours during localized ultrasound hyperthermia in the rat. In normal skin, 40 degrees C hyperthermia only induced a marginal increase in the red blood cell flux. Significant increases occurred after 20 min at 42 degrees C and after 4 min at 44 degrees C. During 44 degrees C hyperthermia maximum fluxes were reached after 24 min. Thereafter, the flow declined and finally approached preheating values. In contrast, in subepidermal tumours 40 degrees C hyperthermia on the average induced a slight decrease of the flux. During 42 degrees C hyperthermia a significant flow decrease was found after 40 min of heating. Follow…
Enhanced effects of aminolaevulinic acid-based photodynamic therapy through local hyperthermia in rat tumours.
2003
The possibility of enhancing aminolaevulinic acid (ALA)-based photodynamic therapy (PDT) by simultaneous application of localised hyperthermia (HT) was evaluated. Treatments of rat DS-sarcomas included: (i) control, (ii) ALA administration (375 mg kg(-1), i.p.), no illumination, (iii) 'nonthermal' illumination, (iv) ALA-PDT: that is, ALA administration, 'nonthermal' illumination, (v) localised HT, 43 degrees C, 60 min (vi) ALA-PDT+HT: ALA administration with full spectrum irradiation resulting in ALA-PDT and HT. Tumour volume was monitored for 90 days or until a target volume (3.5 ml) was reached. No differences were seen between the first three groups, with all tumours reaching the target …
Relation between autoradiographically measured blood flow and ATP concentrations obtained from imaging bioluminescence in tumors following hypertherm…
1993
The effects of moderate local hyperthermia (43.3 degrees C/30 min) on regional blood flow and regional ATP distribution in the amelanotic hamster melanoma A-Mel-3 were investigated by high-resolution techniques. Blood flow and ATP concentrations were measured simultaneously in treated and untreated tumors and in adjacent tissues by means of (14C)-Iodoantipyrine autoradiography and quantitative imaging bioluminescence in consecutive tissue sections at 3, 12 and 24 hr following treatment. Digital image processing and the use of a special algorithm allowed the regional interrelationship of the 2 parameters to be quantified. Measurements revealed a great heterogeneity of blood flow and ATP betw…