Search results for "HYPERTHERMIA"
showing 10 items of 95 documents
Microcirculatory and pH Alterations in Isotransplanted Rat and Xenotransplanted Human Tumors Associated with Hyperthermia
1988
The rationale for considering the use of hyperthermia as an antitumor agent is based on three different mechanisms of action depending on the hyperthermia levels chosen: At moderate hyperthermia levels (40°–42.5° C) heat can increase the radiosensitivity and/or the chemosensitivity. At higher tissue temperatures ( > 42.5° C) hyperthermia acts as a cytotoxic agent since mammalian cells die after heating in a temperature-, time-, and cell cycle-dependent manner. Besides direct effects on the cell membranes, on the cytoskeleton, on metabolic processes, on DNA replication, and on RNA and protein synthesis, indirect effects distinctly modulating the anticancer action of heat have to be considere…
Effects of the exercise in the cerebral blood flow and metabolism: A review
2015
In recent years it has been shown that cerebral blood flow is affected by intense exercise, what may even lead to a reduction in the cognitive capacity. This statement is contrary to the traditional belief that cerebral blood flood remains constant and unaltered even when exercise is performed. During physical exercise of moderate intensity, cerebral blood flow increases in the cerebral areas responsible for movement. Moreover, recent studies have observed that cerebral blood flow decreases during high-intensity exercise as a consequence of a local hyperventilation and vasoconstriction of the areas with lower cerebral activity. Traditionally, the glucose has been considered as the main and …
Effect of hyperthermia on tumor blood flow.
1984
Differences in blood perfusion rates between tumors and normal tissue can be utilized to selectively heat many solid tumors. Blood flow in normal tissues is considerably increased at temperatures commonly applied during localized hyperthermia. In contrast, tumor blood flow may respond to localized heat typically in two different blood flow patterns: Flow may either decrease continuously with increasing exposure time and/or temperature or flow may exhibit a transient increase followed by a decline. A decrease in blood flow at high thermal doses can be observed in most of the tumors, whereas an increase in flow at low thermal doses seems to occur less frequently. The inhibition of blood flow …
Die intraoperative Hyperpyrexie bei Osteogenesis imperfecta-Betroffenen
2000
The aim of this study was to evaluate the influence of different types of anesthesia upon the intra- and postoperative body temperature in osteogenesis imperfecta patients. The development of an intraoperative hyperpyrexia of unknown origin is a typical phenomenon in patients with osteogenesis imperfecta. Body temperatures of up to 40 degrees C are known to complicate the operation. Therefore, in a retrospective study, the pre-, intra- and postoperative body temperature curves of 45 operations under different anaesthesias were measured. Group A underwent a common balanced anaesthesia with the volatile anaesthetic Enfluran in combination with Fentanyl, while group B was operated on under tot…
Analyzing the electrophysiological effects of local epicardial temperature in experimental studies with isolated hearts
2008
As a result of their modulating effects upon myocardial electrophysiology, both hypo- and hyperthermia can be used to study the mechanisms that generate or sustain cardiac arrhythmias. The present study describes an original electrode developed with thick-film technology and capable of controlling regional temperature variations in the epicardium while simultaneously registering its electrical activity. In this way, it is possible to measure electrophysiological parameters of the heart at different temperatures. The results obtained with this device in a study with isolated and perfused rabbit hearts are reported. An exploration has been made of the effects of local temperature changes upon…
Using A Heating Cable Within The Abdomen To Make Hyperthermic Intraperitoneal Chemotherapy Easier: Feasibility And Safety Study In The Swine
2009
International audience; BACKGROUND: Hyperthermic intraperitoneal chemotherapy (HIPEC) is a complex, expensive and time-consuming procedure. Despite its good results in the treatment of peritoneal carcinomatosis, these factors have precluded the wider use of this procedure around the world. We hypothesized that HIPEC could be performed by heating the liquid within the abdomen and thus avoiding the need for an external heating circuit and a pump. The aim of this study was to assess the feasibility and safety of an internal heating device for hyperthermic intraperitoneal chemotherapy in an experimental model. METHODS: Four large-white pigs underwent one-hour open intraperitoneal hyperthermia w…
Do Changes in Tumor Blood Flow Necessarily Lead to Changes in Tissue Oxygenation and in Bioenergetic Status?
1994
An increasing number of investigations carried out in recent years provide evidence suggesting that “chronic” decreases in tumor blood flow and/or tissue oxygenation (e.g., during tumor growth) or acute declines in the tissue perfusion (e.g., following therapeutic measures) might be accompanied by significant reductions in the energy status. In several instances, positive correlations between energy status and tumor blood flow or oxygenation have been reported (Lilly et al., 1985; Evelhoch et al., 1986; Tozer et al., 1989; Vaupel et al., 1989a, 1989b; Steen and Graham, 1991), and these investigations have led to the conclusion that blood flow may be the limiting factor in determining the bi…
Accumulation of purine catabolites in solid tumors exposed to therapeutic hyperthermia
1996
Intensified adenosine triphosphate (ATP) degradation following therapeutic hyperthermia is often observed in solid tumors. As a result, accumulation of purine catabolites can be expected together with formation of protons at several stages during degradation to the final product, uric acid. Proton formation in turn can contribute to the development of heat-induced acidosis. Furthermore, oxidation of hypoxanthine and xanthine may result in generation of reactive oxygen species, which may lead to DNA damage, lipid peroxidation and protein denaturation, thus also contributing to heat-induced cytotoxicity. In hyperthermia experiments a tumor-size-dependent, significant increase in the levels of…
Trattamento endovescicale alternativo al BCG nel carcinoma vescicale NMI a rischio intermedio o elevato
2013
Endovesical treatment as an alternative to BCG for intermediate or high-risk NMI bladder cancer A shortage of BCG is foreseen till the end of 2013. Which will be the management of intermediate and high-risk NMI-BC if BCG will not be available? In patients harboring high-risk NMI tumors, particularly T1G3 and Tis, the first therapeutic choice is radical cystectomy. Device-assisted therapies, although showing promising results, should be considered only for selected patients. In intermediate risk patients, intravesical chemotherapy remains a legitimate option even if BCG is available. Thus, in a period of BCG shortage, intravesical chemotherapy should be offered, preferably preceded by early …
Malignā hipertermija: diagnostikas, ārstēšanas un profilakses sistēmas ieviešana Latvijā
2011
Elektroniskā versija nesatur pielikumus