Tumors brain tumor

The potential for normal brain tissue injury is one of the limiting factors in the use of XRT for brain tumors. Pentobarbital is a cerebral radioprotectant in rodent and primate models after single doses, but is associated with significant risks. Of alternative barbiturates, thiopental given to tats receiving 70-Gy (7000-rad) whole-brain irradiation in a single fraction enhances the 30-day survival similarly to pentobarbital, whereas ethohexital and phenobarbital show no radioprotective activity (250). 

In an animal study of rats exposed by inhalation to ethylene oxide at 10, 33, or 100 ppm for approximately two years (245), and in a separate chronic rat study in which rats were exposed to 50 or 100 ppm of ethylene oxide (240), increased incidences of mononuclear cell leukemia, peritoneal mesothelioma, and various brain tumors have been reported. In an NTP (246) two-year inhalation study of mice at 50 and 100 ppm, alveolar/bronchiolar carcinomas and adenomas, papillary cystadenomas of the harderian gland, and malignant lymphomas, uterine adenocarcinomas, and mammary gland tumors were increased in one or both exposure groups. 

Cancer chemothCTapeutic agents as a rule poorly penetrate the blood brain barrier. Brain tumors are thus not readily treatable by chemotherapy. Diaziquone (at one time known as AZQ) is an exception to this generalization. Treatment of chloranil (213) with the anion from urethane gives intermediate 214, probably by an addition elimination scheme. Displacement of the remaining halogen with aziridine yields diaziquone (215) [.55J. 

Carmustine is a bicyclohexylnitrosourea (BCNU, Fig. 3) with broad spectrum of antineoplastic activity (e.g., lymphomas, multiple myeloma, sarcomas, brain tumors, gastrointestinal tumors, melanomas). At doses of 80-200 mg/m2 it is given i.v. at 6 week s intervals. 

Lomustine (2-chlorethyl-3 cyclohexyl-1 -nutrosourea, CCNU, Fig 3) is a nitrosourea for oral application. It is used for the treatment of Hodgkin s lymphomas, brain tumors and bronchial carcinomas at a dose of 3.5 mg/kg (130 mg/m2) repeated in 6-8 weeks intervals. 

Temozolomide crosses the blood brain barrier and can be used for the treatment of brain tumors (e.g., glioblastoma multiforme). The most common side effects are nausea and vomiting. 

Cancer Neuroblastoma, leukemia, brain tumors and prostate cancer (A) ... 

Seizure disorders are generally categorized as idiopathic or acquired. Idiopathic seizures have no known cause acquired seizure disorders have a known cause, including high fever, electrolyte imbalances, uremia, hypoglycemia, hypoxia, brain tumors, and some drug withdrawal reactions. Once the cause is removed (if it can be removed), the seizures theoretically cease. 

Cornetta K, Croop J, Dropcho E, Abonour R, Kieran MW, Kreissman S, Reeves L, Erickson LC, Williams DA (2006) A pilot study of dose-intensified procarbazine, CCNU, vincristine for poor prognosis brain tumors utilizing fibronectin-assisted, retroviral-mediated modification of CD34-I- peripheral blood cells with 06-methylguanine DNA methyltransferase. Cancer Gene Ther 13 886-895... 

Strobel et al. (101) reported a unique approach to delivery of anticancer agents from lactide/glycolide polymers. The concept is based on the combination of misonidazole or adriamycin-releasing devices with radiation therapy or hyperthermia. Prototype devices consisted of orthodontic wire or sutures dip-coated with drug and polymeric excipient. The device was designed to be inserted through a catheter directly into a brain tumor. In vitro release studies showed the expected first-order release kinetics on the monolithic devices. 

Brain scans are used to study epiiepsy, brain tumors, strokes, Aizheimer s disease, and mentai iiiness. Each of these disorders generates a unique brain activity pattern that differs from the pattern seen in normai brains. Physicians interpret these patterns both for diagnosis and to indicate appropriate treatment. 

The radioactive source need not aiways be introduced into the body. Inoperable brain tumors can be treated with y rays from an extemai source, usuaiiy a sampie of cobait-60. The patient is placed in a position where the y-ray beam passes through the tumor. The patient is moved so that the y rays irradiate the tumor from several angles. In this manner the tumor receives a much higher dose of radiation than the dose received by any surrounding tissues. 

In addition to their inherent self-sustaining properties, brain tumor stem cells may be more resistant to chemotherapy and radiation therapy than other tumor cells. Bao et al. (2006) found glioma stem cells (CD133+) were relatively radioresistant compared to CD133- tumor cells and preferentially activated the DNA damage checkpoint response. This relative resistance to standard treatment approaches of tumor stem cells compared to the majority of other cells within a tumor may underlie our current inability to cure patients with aggressive brain tumors such as glioblastoma. 

CXCL12 Stimulates Brain Tumor Cell Proliferation and Survival... 

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