Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The early effects of in vivo platinum-rhodamine (PtR) chemotherapy on tumor high-energy phosphorous metabolism was investigated using phosphorus-31 (31P) magnetic resonance spectroscopy (MRS), magnetic resonance imaging (MRI), and histologic examination in a subcutaneously implanted hamster melanoma model. PtR was chosen because of its potential antimitochondrial and antineoplastic properties. All melanomas were clearly observed on both T1- and T2-weighted images (T1WI and T2WI), with viable tumor regions generally characterized by low to intermediate intensity on T1WI and high intensity on T2WI. Necrotic regions were more variable in appearance, depending on the amount of cystic fluid and hemorrhage. No changes were detected on either T1WI or T2WI within 90 minutes of a tumoristatic dose of PtR (40 mg/kg) by visual examination, but slight differences were seen on calculations of relative signal intensities. However, this same dose of PtR caused a 50% drop in tumor ATP and phosphocreatine content (relative to Pi) measured by 31P MRS within 90 minutes of drug injection. Magnetic resonance spectroscopy appears to offer a sensitive means of detecting the earliest biochemical effects of chemotherapeutic agents that are known to affect tumor bioenergetics.
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PMID:Magnetic resonance imaging of implanted melanomas before and after chemotherapy. Relation to 31P magnetic resonance spectroscopy and tumor histology. 207 5

In the present study, the intracellular localization of titanium was analyzed in three xenografted human adenocarcinomas of the colon sigmoideum (S 90), the stomach (M-Stg 4), and the lung (L 261) in dependence on the time after application of a single therapeutic dose (80 mg/kg) of the organometallic antitumor agent titanocene dichloride (C5H5)2TiCl2. The investigations were performed by use of electron energy loss spectroscopy (EELS), a method which allows microanalysis in ultrathin sections, in combination with electron spectroscopic imaging (ESI), which offers the possibility to image the two-dimensional localization and distribution of light- and medium-weight elements in animal tissues. In all three tumors which were studied, titanium was at first detected within the nucleus and, some hours and days later, it was additionally found in cytoplasmic lysosomes. In the colon and lung tumors S 90 and L 261, already 12 hr after treatment, titanium was traceable as tender granules in the nuclear chromatin. During the following days, it was then accumulated in certain areas of the nuclear heterochromatin and, in the case of the L 261 tumor, also in the nucleolus. Maximum concentrations were attained in the nuclei and nucleoli at 48 hr after substance application. Thereafter, titanium was increasingly incorporated into cytoplasmic lysosomes which are known to be involved in intracellular degrading and digesting processes and which occurred in increased numbers in treated tumor cells. Regarding the stomach carcinoma M-Stg 4, titanium was recognized in the nuclear heterochromatin only 1 and 2 days after application of titanocene dichloride. At 48 hr, it was additionally detected in cytoplasmic lysosomes. In all cases where titanium was found accumulated in the nucleus and in lysosomes, phosphorus was simultaneously enriched in a similar local distribution and a concentration which even exceeded that within phosphorus-rich areas, e.g., the nuclear heterochromatin and cytoplasmic ribosomes. These results confirm a primary interaction of titanium-containing metabolites deriving from titanocene complexes with nucleic acid molecules, especially with nuclear DNA. They suggest the formation of aggregates between nucleic acids and titanium-containing metabolites which are obviously extruded out of the nuclei and incorporated into cytoplasmic lysosomes, known to be involved in intracellular digesting processes.
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PMID:Intracellular localization of titanium within xenografted sensitive human tumors after treatment with the antitumor agent titanocene dichloride. 210 Jan 49

Magnetic resonance imaging (MRI) is a powerful tool for accurate assessment of the anatomic extent of head and neck neoplasms. The development of methods for spatial localization by use of multiply tuned radio frequency coils that permit the measurement of multiple nuclear MR spectra (1H and 31P) from precisely defined volumes of interest has provided a basis for integrating spectroscopy into the clinical MRI examination. This offers a means for noninvasive monitoring of relative concentrations of mobile metabolites within a tumor. With the use of imaging to determine proper coil placement, a test-retest variance of about 17% is seen on MR spectroscopy. Data are presented from MRI/MRS studies for four head and neck lesions: (1) a squamous cell carcinoma of the lip; (2) a juvenile angiofibroma extending into the nasal cavity; (3) a massive chondrosarcoma of the nasal septum; and (4) a cervical nodal metastasis of a squamous cell carcinoma of the pharynx. Spectra are evaluated by comparison of relative concentrations of phosphorus compounds. The concentrations of phosphomonoesters and phosphodiesters are significantly higher in the neoplasms studied than in normal skeletal muscle. The developing role of integrated MRI/MRS to monitor the response of malignant neoplasm to radiation therapy is discussed.
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PMID:31P localized magnetic resonance spectroscopy of head and neck tumors--preliminary findings. 212

The authors studied the usefulness of hydrogen-1 T2 measurements and phosphorus-31 magnetic resonance (MR) spectroscopy as indicators of prognosis and monitors of response to therapy in a group of patients with soft-tissue sarcomas. All eight patients were treated with combined local hyperthermia and fractionated radiation therapy, followed by surgical resection of the tumor. Each patient underwent T2 measurements and five patients underwent MR spectroscopy (phase encoded in one dimension) before treatment, after the first hyperthermia treatment, at the end of the therapy course, and just before surgery. Catheter thermometry was performed at each hyperthermia treatment. The T2 and MR spectroscopic variables were compared with thermometric data and the histologic findings from the complete surgical specimen. Changes in T2 correlated with histologic grade of tumor and thermometric data. The pretherapy tumor pH correlated positively, and changes during therapy in pH, ratio of phosphocreatine to inorganic phosphate (Pi), ratio of nucleoside triphosphate to Pi, and the phosphomonoester signal-to-noise ratio correlated negatively, with the percentage of tumor necrosis on the surgical specimen. These preliminary data suggest MR imaging and MR spectroscopy may be useful in the evaluation of such patients before and during therapy.
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PMID:Soft-tissue sarcomas: MR imaging and MR spectroscopy for prognosis and therapy monitoring. Work in progress. 215 37

We have obtained localized, water-suppressed proton magnetic resonance spectra from eleven astrocytomas in vivo. Localized phosphorus spectra were also obtained from three of these tumors. All tumors were examined prior to surgery, radiotherapy or chemotherapy. Examinations were performed with a commercially available 1.5 Tesla combined imaging and spectroscopy system using a stimulated echo pulse sequence for protons and an ISIS pulse sequence for phosphorus. A relatively high lactate resonance intensity correlated with a more malignant histological tumor grade and more aggressive behaviour. The resonance intensity of N-acetylaspartate/creatine was decreased and choline/creatine was increased, but these did not reliably discriminate between tumor grades. Other unidentified resonances not present in spectra of normal brain were sometimes seen. Proton magnetic resonance spectroscopy provides a new method for determining the metabolic behaviour of astrocytomas that may be useful in the clinical assessment of patients with these tumors.
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PMID:Proton and phosphorus magnetic resonance spectroscopy of human astrocytomas in vivo. Preliminary observations on tumor grading. 216 42

Longitudinal study of metabolic change after cerebral infarction was done using nuclear magnetic resonance spectroscopy (MRS). Localized completed infarction model induced by intra-cranial ligation of the middle cerebral artery and extra-cranial ligation of common carotid artery in rats was utilized. In acute study the proton MRS revealed a sharp increase of lactic acid but the phosphorus -31 MRS did not show prominent changes. This increase of lactic acid persists 24 hours after the induction of infarction. In chronic study the spectroscopic pattern of the infarcted brain showed minimum difference from the control normal brain. However the signal intensity of phosphomonoester was significantly higher in the infarcted brain. Our study in acute phase suggests that the proton MRS is a sensitive probe to detect an early metabolic deterioration induced by ischemic insult. And the increase of phosphomonoester in chronic infarcted brain may imply that a gliosis seen in chronic infarction has a metabolic resemblance to neonate brain and neoplasm.
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PMID:[Proton and phosphorus-31 nuclear magnetic resonance spectroscopy in experimental cerebral infarction in rats]. 217 75

Giant-cell reparative granuloma (GCRG) is an uncommon benign reactive intraosseous lesion. It occurs in the skull, jaw, hand, foot, and facial bones and rarely in other skeletal sites. It is a solitary, lytic, expanded lesion and infrequently may extend into the surrounding soft tissue. Histologically, it is composed of fibrous stroma with spindle-shaped fibroblasts, multinucleated giant cells, and inflammatory mononuclear cells. Areas of hemorrhage are uniformly present. It may be difficult to distinguish this entity from an aneurysmal bone cyst, giant-cell tumor, or brown tumor of hyperparathyroidism because of roentgenographic and histologic similarities. Accurate diagnosis is essential for appropriate treatment; serum calcium, phosphorus, and parathyroid hormone levels should be measured. Curettage and bone graft are effective treatments for both primary lesions and recurrences. Second recurrences are rare.
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PMID:Giant-cell reparative granuloma of the hand and foot bones. 222 31

Little notice has been paid in the surgical literature to problems with psychoeffective lithium, which by interfering with adenylate cyclase affects thyroid and parathyroid function, causing hypercalcemia, hyperparathyroidism, and hypothyroidism. Seven patients with lithiumogenic hyperparathyroidism occurring after years of lithium therapy underwent treatment and manifested osteoporosis (n = 2), hypertension (n = 2), nephrolithiasis (n = 1), coma (n = 1), rising hypercalcemia (n = 1), goitrous myxedema (n = 4), nephrogenic diabetes insipidus (n = 2), renal failure (n = 2), and hyperlipidemia (n = 1). Disease-directed parathyroidectomy (without morbidity) was curative. Unique laboratory findings included normal serum phosphorus and reduced urinary calcium and cyclic adenosine monophosphate values. Three separate cases of thyroid carcinoma after long-term lithium therapy were also treated, being preceded by myxedema (n = 2) and concurrent with hyperparathyroidism (n = 1). There has been only one previous report of lithium-associated thyroid carcinoma. All patients taking lithium should undergo surveillance for thyroid and parathyroid dysfunction and neoplasia, and appropriate surgical and medical treatment should be considered in each situation. Although hyperparathyroidism may be reversible with lithium discontinuance, such therapy may be obligatory for patient well-being, thus dictating parathyroidectomy.
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PMID:Lithiumogenic disorders of the thyroid and parathyroid glands as surgical disease. 224 24

The classification of giant cell lesions of the maxillofacial skeleton is one that remains controversial. Classifying giant cell lesions of the jaw as granulomatous based solely on location seems inappropriate. The categories of benign or malignant are more realistic. Benign lesions may then be subdivided into aggressive and nonaggressive. Multifocal giant cell lesions strongly suggest the brown tumor of hyperparathyroidism. Serum chemistry tests including calcium, phosphorus, ionized calcium, and PTH levels should routinely be obtained when a giant cell lesion is suspected. A case of benign, aggressive, multifocal central giant cell lesions of the maxillofacial skeleton, in the absence of either primary or secondary hyperparathyroidism is presented. Whether this represents metastasis from the initial lesion, metabolic osteoclastic dysfunction, or a new entity, craniofacial giant cell dysplasia, is unknown.
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PMID:Multifocal central giant cell lesions of the maxillofacial skeleton: a case report. 230 39

Positron emission tomography (PET) of 2(18F)-fluoro-2-deoxy-D-glucose (FDG) and volume-selective phosphorus-31 magnetic resonance spectroscopy (31P-MRS) are methods used to assess the energy metabolism of the brain. Both methods were studied with respect to their contribution to differential diagnosis in 23 patients with various brain tumors. The various neuroectodermal tumors differed with respect to their metabolic rate for glucose (MRGL). Benign and malignant tumors could be better differentiated by using tumor metabolism relative to contralateral brain and by evaluating heterogeneities in tumors. Low-grade gliomas usually showed normal 31P-MR spectra; high-grade gliomas were characterized by reduced and often split phosphodiester peaks and alkaline pH. Meningiomas, which had variable MRGL, typically showed extremely low phosphocreatine levels, reduced phosphodiesters, and alkaline pH. We concluded that FDG-PET and 31P-MRS examine different aspects of tumor metabolism. Therefore, both can contribute independently and complementarily to the differential diagnosis of brain tumors.
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PMID:Positron emission tomography of fluorine-18-deoxyglucose and image-guided phosphorus-31 magnetic resonance spectroscopy in brain tumors. 230 1


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