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)

For the first time results of investigations on rats with radioactive compounds in autochtonal tumors of the central nervous system, induced via placenta by Ethyl-Nitrose-Urea (ENU), are reported. In contrast to transplantation tumors the tumors induced by ENU are comparable in regard to the szintigrafic results with human brain tumors. The radiopharmaceuticals 131I-HSA, 99mTc-Pertechnetate, 203Hg-Chlormerodrin and 113m/111In-DTPA are similar to human brain tumors taken up by the ENU-tumors. For these findings it may be important, that the ENU-tumors are of neurogenic origin and do not differ histologically from the human brain tumors. The accumulation of the radioactive substances in ENU-tumors can be explained with the lesion at the blood-brain-barrier and at the blood-nerv-barrier. Therefore, it is discussed that the mechanism of the uptake is similar in human brain neoplasms and in ENU-tumors of the brain. The ENU-tumor model is suitable for testing new radiopharmaceuticals before their application in men.
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PMID:[Experimental investigations on the accumulation of radioactive compounds in autochtonal tumors in the rat (author's transl)]. 17 56

Hypertrophy of the renal columns of Bertin may present as a mass, at times difficult to distinguish from neoplasia or cyst. Herein, we present a case characterized by the inability of this lesion to absorb 99mTc DTPA (99mTechnetium diethylenetriaminepentaacetic acid) isotope on two separate renal studies.
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PMID:Pseudotumor of kidney. 21 80

The pharmacodynamics of technetium-99m stannous citrate were studies in Yale-Swiss mice bearing a sarcoma-like transplantable brain tumor, and the renal kinetics were determined in normal mice. Using a rating system based on tumor uptake and tumor-to-brain, tumor-to-blood, and tumor-to-skin ratios, the data obtained with this compound were compared with similar data obtained previously in the same model with Tc-99m Fe-(ascorbic acid), Tc-99m Fe-(ascorbic acid)-DTPA, Tc-99m Sn-DTPA, [99mTc] pertechnetate, and [99mTc] pertechnetate with perchlorate predose. Technetium-99m stannous citrate does not appear to achieve tumor localization by a mode different from these other Tc-99m-labeled compounds, nor does it show any potential advantage as a scanning agent in the tumor model.
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PMID:Technetium-99m stannous citrate brain-tumor uptake in mice: concise communication. 89 90

Experience with Radio Isotope Myelography is reported here. 169Yb-DTPA as a tracer was intrathecally injected at lumbar region in twenty three patients with various spinal cord lesions. The first scanning is perfomed after comfirming by gamma-camera that the tracer reaches to the lesion, the second and the third scannings are done according to the ascending rate of the tracer. (I) Normal scintimyelogram (A) In normal case, the shape of the Radio Isotope Myelogram well corresponds the shape of anatomical subarachnoid space. (B) In normal adult cases, the tracer comes up to the cisterna magna in 20-25 minutes after the lumbar injection. Therefore, the scintimyelographic diagnosis should be made not only by the shape but also by the ascending rapidity of the tracer. (II) Abnormal scintimyelogram Abnormal scintimyelograms could be summarized as following three categories. (A) "Delay": It means delay of the ascending of the tracer. Besides, "Transient delay" found in a case of Arnord-Chiari's malformation was proposed. (B) "Partial block": It meas a defect at the level of the lesion. This "Partial block" were observed in cases of spinal cord angioma, cervical spondylosis and spinal cord tumor etc. (C) "Complete block": It means the stagnation of the tracer below the lesion. To sum up, Rario Isotope Myelography, especially in partial block, can more easily and more sensitively represent the maximum extent of the spinal cord lesion than other myelographic study or angiographic one. On the other hand, we can not qualitatively diagnose about the lesions by its indistinct border.
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PMID:[Experience with radio isotope myelography from neurosurgical aspects (author's transl)]. 98 90

Sixty-three patients with malignant glioma undergoing chemotherapy and radiotherapy were evaluated with electroencephalography, 99mTc-DTPA imaging, and computed tomography (CT). Tumor size, central lucency, contrast enhancement, surrounding edema, and ventricular size were assessed. CT findings were found to be reliable and often predicted the clinical course. Tumor size, central lucency, and contrast enhancement increased in patients with clinical deterioration and decreased in those with improvement. The CT scan also provided additional information of value in adjunctive therapy, such as the presence of cysts or ventricular obstruction. In general, CT gave a more complete profile of tumor characteristics than other diagnostic modalities.
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PMID:Computed tomography in the evaluation of malignant glioma before and after therapy. 108 56

Octreotide is a synthetic analog of the peptide hormone somatostatin (SMS). A wide variety of tumors express enhanced numbers of SMS receptors, notably neuroendocrine tumors and lymphomas, but also some of the more common adenocarcinomas. Octreotide contains only eight amino acids, some of which are in the (D) configuration in order to enhance the stability of the molecule in vivo. Tyrosine and DTPA-containing analogs of octreotide have been synthesized and labeled with iodine-123 and indium-111, respectively, with the intention of targeting SMS receptor-containing tumors for diagnostic purposes. Both radiopharmaceuticals demonstrate a high sensitivity and specificity for these tumors, indicating a clinical role for these agents in management of these diseases. Lessons can be learned from the success of these agents when designing improved antibody-based molecules. Tumor uptake of radiolabeled octreotide is very rapid, occurring within minutes of administration. Blood clearance is also rapid, such that tumors are soon visible even in areas of high blood background. An interesting finding has been the differences between the pharmacokinetics of the iodinated and indium-labeled species. Although the majority of 123I-Tyr3-octreotide undergoes hepatobiliary excretion, 111In-DTPAPhe1-octreotide is eliminated predominantly by the kidneys. These results suggest that the smallest possible antibody-like tracers are likely to have advantages over native immunoglobulins and conventional Fab-like fragments.
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PMID:Radiolabeled octreotide. What lessons for antibody-mediated targeting? 128 34

A man presented with recurrent renal cell carcinoma, complicated with acute pyelonephritis, 3 months status post partial nephrectomy. He underwent cystourethroscopy and a bilateral retrograde pyelogram, then was referred for a Tc-99m DTPA renal study; the images showed an initial photon-deficient area of the right kidney being gradually filled-in by radiotracer with further extension laterally, indicating urinary extravasation. 16 days later this area was aspirated, yielding 5 ml of yellowish fluid with clots consistent with necrotic tumor and pus.
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PMID:Urinary extravasation from the kidney of recurrent renal cell carcinoma. 129 73

The pharmacokinetics of various radiopharmaceuticals following i.v. administration in mice and rats has been studied and compared. Before injection the radiochemical purity (RP) of the compounds were determined by HPLC and PAGE. In all cases RP-s were higher than 90%. The biodistribution of 99mTc labelled anti CEA IgG was studied in mice bearing human colon carcinoma xenografts. Animals with different tumour weights showed different blood kinetic and tumor uptake. The pilot clinical study of the 99mTc labelled anti melanoma Fab and 111-In-DTPA labelled anti melanoma F(ab')2 showed differences in the pharmacokinetic parameters. (99mTc labelled: comp.A. 84.6%; T1/2:0.6 h, 111-In-labelled: comp.A.: 46%, T1/2 1.5 h.) The various isonitrile derivatives synthetized in our laboratory were labelled with 99mTc and the biodistribution were tested in rats. The kinetic study showed that all the three molecules have different half lives in the heart and liver (T1/2 for heart ranged 5.1-18.6 h, for liver T1/2:1.2-2.5 h). Reversed phase HPLC study of the collected bile showed the 15-100% of injected compounds are metabolized during hepatic excretion. Literature data and our recent observations confirm that the knowledge of pharmacokinetics of radiolabelled compounds both in research, development and clinical practice is of basic importance.
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PMID:Pharmacokinetics of radiopharmaceuticals. 130 81

We carried out a retrospective analysis of about 100 surgical cases of mediastinal, pleural, chest wall and pulmonary disorders in order to determine the clinical application and efficacy of MRI (magnetic resonance imaging) of the thorax. Coronal and/or axial image of T1-weighted images were obtained in all cases, and T2-weighted or gadolinium-DTPA contrast-enhanced T1-weighted images were additionally obtained in several selected cases. All MR images were compared with findings of chest X-ray, CT and IVDSA (intravenous digital subtraction angiography) as appropriate. As a result, MR images were considered to provide additional information to that obtained by conventional techniques of chest X-ray and CT, in demonstrating chest wall invasion of pulmonary carcinoma, detecting hilar masses, which were difficult to distinguish from vessels, and in defining mediastinal masses. The anterior segment of the diaphragm is clearly depicted, aiding the differentiation of Morgagni hernia from other entities. Tuberculoma showed peripheral enhancement in Gd-enhanced T1 WI, which was distinctly different from the enhancing pattern of carcinomas. With the use of surface coil, the pleura and chest wall anatomy were clearly demonstrated. It is hoped that the wide application of this technique will increase the diagnostic accuracy of chest wall tumor invasion.
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PMID:[MRI of the thorax; clinical application and efficacy in 100 thoracic diseases]. 130 34

The authors investigated the magnetic resonance appearance of hepatocellular carcinoma using a 1.5-Tesla magnet. Twenty-four patients with pathologically proven hepatocellular carcinoma had magnetic resonance imaging (MRI) studies, which were retrospectively reviewed. All patients were imaged with at least two of the following techniques: (1) T1-weighted (T1W), (2) T1-weighted with Gd-DTPA enhancement (T1W-E), (3) T2-weighted (T2W), (4) proton density (PD), and (5) gradient-recalled echoes (GRE). T1W images were equal to T2W images for tumor detection using a grading system. T1W images were slightly better than T2W images for the total number of lesions detected. The other pulsing techniques (PD, T1W-E, and GRE) detected fewer lesions. Eight cases of hepatocellular carcinoma (33%) had nonhomogeneous increased signal intensity on both T1W and T2W images. The authors conclude that T1W images are equal to T2W images for detection of hepatocellular carcinoma. The authors also conclude that 33% of hepatocellular carcinomas have an imaging pattern with increased signal intensity on both T1W and T2W images. This pattern is atypical for most other hepatic masses and hence can be used to suggest the mass is hepatocellular carcinoma.
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PMID:MR imaging of hepatocellular carcinoma at 1.5 Tesla. 131 48


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