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1.
Acta Neuropathol Commun ; 8(1): 92, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32586411

RESUMEN

The choroid plexus (CP) is a highly vascularized structure located in the ventricles that forms the blood-CSF barrier (BCSFB) and separates the blood from the cerebrospinal fluid (CSF). In addition to its role as a physical barrier, the CP functions in CSF secretion, transport of nutrients into the central nervous system (CNS) and a gated point of entry of circulating immune cells into the CNS. Aging and neurodegeneration have been reported to affect CP morphology and function and increase protein leakage from blood to the CSF. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease associated with both upper and lower motor neuron loss, as well as altered proteomic and metabolomic signatures in the CSF. The role of the BCSFB and the CP in ALS is unknown. Here we describe a transcriptomic and ultrastructural analysis of BCSFB and CP alterations in human postmortem tissues from ALS and non-neurologic disease controls. ALS-CP exhibited widespread disruptions in tight junctional components of the CP epithelial layer and vascular integrity. In addition, we detected loss of pericytes around ALS blood vessels, accompanied by activation of platelet aggregation markers vWF and Fibrinogen, reminiscent of vascular injury. To investigate the immune component of ALS-CP, we conducted a comprehensive analysis of cytokines and chemokine panels in CP lysates and found a significant down-regulation of M-CSF and V-CAM1 in ALS, as well as up-regulation of VEGF-A protein. This phenotype was accompanied by an infiltration of MERTK positive macrophages into the parenchyma of the ALS-CP when compared to controls. Taken together, we demonstrate widespread structural and functional disruptions of the BCSFB in human ALS increasing our understanding of the disease pathology and identifying potential new targets for ALS therapeutic development.


Asunto(s)
Esclerosis Amiotrófica Lateral/patología , Barrera Hematoencefálica/patología , Plexo Coroideo/patología , Esclerosis Amiotrófica Lateral/inmunología , Esclerosis Amiotrófica Lateral/metabolismo , Barrera Hematoencefálica/inmunología , Barrera Hematoencefálica/metabolismo , Plexo Coroideo/inmunología , Plexo Coroideo/metabolismo , Citocinas/líquido cefalorraquídeo , Citocinas/inmunología , Citocinas/metabolismo , Humanos , Activación Plaquetaria/fisiología , Transcriptoma
3.
Mol Psychiatry ; 18(7): 781-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23608917

RESUMEN

Whole-exome sequencing of individuals with mild cognitive impairment, combined with genotype imputation, was used to identify coding variants other than the apolipoprotein E (APOE) ε4 allele associated with rate of hippocampal volume loss using an extreme trait design. Matched unrelated APOE ε3 homozygous male Caucasian participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) were selected at the extremes of the 2-year longitudinal change distribution of hippocampal volume (eight subjects with rapid rates of atrophy and eight with slow/stable rates of atrophy). We identified 57 non-synonymous single nucleotide variants (SNVs) which were found exclusively in at least 4 of 8 subjects in the rapid atrophy group, but not in any of the 8 subjects in the slow atrophy group. Among these SNVs, the variants that accounted for the greatest group difference and were predicted in silico as 'probably damaging' missense variants were rs9610775 (CARD10) and rs1136410 (PARP1). To further investigate and extend the exome findings in a larger sample, we conducted quantitative trait analysis including whole-brain search in the remaining ADNI APOE ε3/ε3 group (N=315). Genetic variation within PARP1 and CARD10 was associated with rate of hippocampal neurodegeneration in APOE ε3/ε3. Meta-analysis across five independent cross sectional cohorts indicated that rs1136410 is also significantly associated with hippocampal volume in APOE ε3/ε3 individuals (N=923). Larger sequencing studies and longitudinal follow-up are needed for confirmation. The combination of next-generation sequencing and quantitative imaging phenotypes holds significant promise for discovery of variants involved in neurodegeneration.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/genética , Disfunción Cognitiva/genética , Exoma/genética , Predisposición Genética a la Enfermedad/genética , Hipocampo/patología , Poli(ADP-Ribosa) Polimerasas/genética , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/psicología , Apolipoproteína E3/genética , Atrofia/patología , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/patología , Estudios de Cohortes , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Neuroimagen , Poli(ADP-Ribosa) Polimerasa-1 , Polimorfismo de Nucleótido Simple , Población Blanca/genética
4.
Health Phys ; 85(6): 662-77, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14626318

RESUMEN

This paper provides the results of an in situ gamma-ray spectrometry intercomparison that was held from 18-21 October 1999, in Grand Junction, CO. This intercomparison was a collaborative effort between the U.S. Department of Energy's Environmental Measurements Laboratory and the U.S. Environmental Protection Agency's Office of Radiation and Indoor Air. It featured measurements of a background location and the Walker Field Calibration Pads. In this paper, the in situ gamma-ray measurements of the background location were compared to soil samples, and the in situ measurements of the Walker Field Calibration Pads were compared to corrected reference values. The results showed that 84% of the in situ gamma-ray measurements of 226Ra, 232Th, and 40K at the background location fell within 20% of the soil sample mean. Similarly, in situ gamma-ray measurements of the Walker Field Calibration Pads showed that 77% of the in situ concentrations fell within 20% of the corrected reference values.


Asunto(s)
Calibración/normas , Radioisótopos de Potasio/análisis , Radio (Elemento)/análisis , Contaminantes Radiactivos del Suelo/análisis , Espectrometría gamma/métodos , Espectrometría gamma/normas , Torio/análisis , Radiación de Fondo , Dosis de Radiación , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría gamma/instrumentación , Estados Unidos
5.
J Nucl Med ; 42(12): 1805-14, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11752077

RESUMEN

UNLABELLED: Elevated levels of choline (trimethyl-2-hydroxyethylammonium) and choline kinase (CK) activity in neoplasms have motivated the development of positron-labeled choline analogs for noninvasive detection of cancer using PET. The aim of this study was to further evaluate [(18)F]fluorocholine (fluoromethyl-dimethyl-2-hydroxyethylammonium [FCH]) as an oncologic probe in comparison with several other closely related molecules. METHODS: FCH, [(18)F]fluoromethyl-methylethyl-2-hydroxyethylammonium (FMEC), [(18)F]fluoroethyl-dimethyl-2-hydroxyethylammonium (FEC), and [(18)F]fluoropropyl-dimethyl-2-hydroxyethylammonium (FPC) were synthesized through [(18)F]fluoroalkylation reactions. In vitro phosphorylation rates of the (18)F-labeled choline analogs and [methyl-(14)C]choline (CH) were studied using yeast CK. Several choline radiotracers were also evaluated in cultured PC-3 human prostate cancer cells. Data on chemical stability, radiation dosimetry, and toxicity of FCH were obtained. PET studies with FCH were performed on a patient with prostate cancer and a patient with a brain tumor. RESULTS: FCH and FMEC revealed in vitro phosphorylation by CK that was similar to that of choline, whereas rates of phosphorylation of FEC and FPC were 30% (P < 0.01) and 60% (P < 0.01) lower, respectively. Accumulations of FCH, CH, and FPC in cultured PC-3 cancer cells were comparable, whereas uptake of FEC was approximately one fifth that of FCH. Dosimetry estimates using FCH biodistribution data in mice indicated that the kidneys are radiation-dose-critical organs for FCH. PET images of a patient with recurrent prostate cancer showed uptake of FCH in the prostatic bed and in metastases to lymph nodes. FCH PET showed uptake in malignancies in a patient with metastatic breast cancer. PET revealed FCH uptake in biopsy-proven recurrent brain tumor with little confounding uptake by normal brain tissues. CONCLUSION: The fluoromethyl choline analog FCH may serve as a probe of choline uptake and phosphorylation in cancer cells, whereas fluoroethyl (FEC) and fluoropropyl (FPC) analogs appear to have relatively poorer biologic compatibility. Preliminary PET studies on patients with prostate cancer and with breast cancer and brain tumor support further studies to evaluate the usefulness of FCH as an oncologic probe.


Asunto(s)
Radioisótopos de Flúor , Compuestos de Amonio Cuaternario , Radiofármacos , Tomografía Computarizada de Emisión , Adulto , Anciano , Animales , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Colina/análogos & derivados , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Neoplasias de la Próstata/diagnóstico por imagen , Radiometría , Distribución Tisular
6.
Clin Positron Imaging ; 3(4): 147, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11150750

RESUMEN

The purpose of this study was to develop and evaluate an F-18 labeled choline tumor imaging agent.FCH was synthesized through the intermediate F-18 fluorobromomethane that was used to alkylate dimethylethanolamine. The isolated FCH was evaluated in PC-3 human prostate cancer cells, PC-3 human prostate cancer xenograft studies, and human prostate and brain tumor patients.FCH was accumulated at a slightly lower rate than FDG in the cultures of PC-3 cells. Inhibition of choline transport and phosphorylation by hemicholinium-3 resulted in a 90% decrease in FCH uptake without altering FDG uptake. FCH had a similar biodistribution as C-14 choline in mice, with the liver and kidneys being the primary sites of uptake. Tumor uptake of FCH and FDG were comparable at 45-60 mins after injections. The tumor:blood ratio was higher for FCH (5.3 +/- 2.4) than for FDG (3.2 +/- 0.3). Brain uptake of FCH was 10% that of FDG. FCH-PET studies were compared to FDG-PET studies. In the prostate cancer patients, more lesions have been seen on the FCH studies than on the FDG studies, and the standardized uptake values (SUV) have been higher with the FCH. Decreases in FCH-PET SUV have been noted in patients treated by androgen deprivation. Patients with suspected recurrent brain tumors have had more clearly defined abnormal accumulation on the FCH-PET scans than on the FDG-PET scans. The FCH is not accumulated by normal cortex.FCH is a promising imaging agent for the evaluation of metastatic prostate cancer and recurrent brain tumor.

7.
Altern Lab Anim ; 28(3): 461-72, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-25419927

RESUMEN

A new direct-contact toxicity test, the solid-phase flash assay, which utilises photobacteria in direct contact with soil particles during the exposure, was evaluated on four soil samples. Samples HTNT1 and HTNT2 originated from former military sites in Germany, and were highly contaminated with nitroaromatics (approximately 20g/kg), lead and polycyclic aromatic hydrocarbons. Samples LMKW1 and LMKW2, from bioremediation stacks in Germany, were mainly contaminated with mineral oils. The solid-phase flash assay was applied to soil-water slurries, and the results were compared with the toxicity data for soil-water extracts obtained by using various conventional ecotoxicological tests, in which photobacteria, crustaceans, protozoa and algae were used as test organisms. The LMKW1 and LMKW2 samples were not toxic (EC20 > 12.5%) according to all the tests applied, except for the Photobacterium phosphoreum conventional luminescence-inhibition test for LMKW1 (15-minute EC20 = 5.4%(. The HTNT1 and HTNT2 samples were toxic according to all the tests applied, with the majority of EC20 values being lower than 1%. The solid-phase flash assay (1 minute of extraction and 30 seconds of exposure time) gave comparable results to the conventional tests. Therefore, this flash assay could be applied as a fast screening test in parallel with conventional toxicity tests that use soil 24-hour extracts. The flash assay results will be ready by the start of the conventional assays, and could serve as range-finders for these slower and more expensive tests.

8.
J Immunol ; 163(12): 6551-6, 1999 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-10586048

RESUMEN

Although generally thought of as a T cell-driven autoimmune disease, recent studies in experimental allergic encephalomyelitis (EAE), the animal model of multiple sclerosis, suggest a significant role for innate immune mechanisms. To address the possibility that the complement system plays a central role in these diseases, we developed a transgenic mouse with astrocyte-targeted production of a soluble inhibitor of complement activation, complement receptor-related protein y (sCrry). Here, we show that sCrry transgenic mice are either fully protected against EAE or develop significantly delayed clinical signs. These results indicate that complement activation may have an essential role in the pathogenesis of the disease and that complement-mediated events may occur early during the effector phase of EAE. Furthermore, this work underscores the importance of humoral immunity in amplifying a T cell-initiated pathogenic process.


Asunto(s)
Sistema Nervioso Central/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/prevención & control , Receptores de Complemento/biosíntesis , Animales , Sistema Nervioso Central/citología , Sistema Nervioso Central/metabolismo , Cerebelo/química , Cerebelo/metabolismo , Cerebelo/patología , Complemento C4/metabolismo , ADN Complementario/genética , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/patología , Regulación de la Expresión Génica/inmunología , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/inmunología , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas de la Mielina , Glicoproteína Asociada a Mielina/inmunología , Glicoproteína Mielina-Oligodendrócito , Regiones Promotoras Genéticas/inmunología , Receptores de Complemento/genética , Receptores de Complemento 3b
9.
Altern Lab Anim ; 27(3): 359-66, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-25470674

RESUMEN

The chemical composition and toxicity of five phenolic wastewater samples collected from the Kohtla-Järve (Estonia) oil-shale industry region were analysed. The total phenolic contents (HPLC data) of these samples ranged from 0.7mg/l to 195mg/l. A total of 11 phenolic compounds were found in the wastewater samples, the most abundant being phenol (up to 84mg/l) and p-cresol (up to 74mg/l). Artificial phenolic mixtures were also composed, to mimic the content of phenolic compounds in the wastewater samples. The theoretical toxicities of these artificial mixtures were calculated by using the toxicities of the individual phenolic constituents to photobacteria (the BioTox™ test) and were assumed to have an additive mode of action. From the BioTox data, the additive toxic effects of phenolic compounds in the artificial mixtures were confirmed to be highly probable. The toxicities of the wastewater samples and their artificial phenolic analogues (mixtures) were studied by using a battery of Toxkit microbiotests (Daphtoxkit F™ magna, Thamnotoxkit F™, Protoxkit F™ and Rotoxkit F™) and three photobacterial tests (Microtox™, BioTox™ and Vibrio fischeri 1500). The wastewaters were classified as toxic (two samples), very toxic (two samples) and extremely toxic (one sample). Comparison of the test battery responses showed that the industrial wastewaters were 2-28-fold more toxic than the respective artificial phenolic mixtures. The photobacterial tests proved to be the most appropriate for screening purposes. This was the first attempt to use a test battery approach in the toxicity testing of Estonian wastewaters. The study showed that the toxicity of oil-shale industry wastewaters could not be predicted solely on the basis of their phenolic composition, since only 7-50% of their toxicity was shown to be due to phenolic compounds. It is true, to a certain extent, that the majority of environmental samples are usually very complex and contain various types of pollutants. As even a full chemical analysis (which is very expensive) can easily miss the constituent(s) with the greatest toxic effect(s), the use of toxicity tests in parallel to chemical analysis should be encouraged.

10.
Chemosphere ; 37(2): 301-18, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9650267

RESUMEN

Phenolic composition, toxicity and biodegradability of three different phenolic leachates/samples was studied. Samples A and C were the leachates from the oil-shale industry spent shale dumps at Kohtla-Järve, Estonia. Sample B was a laboratory-prepared synthetic mixture of 7 phenolic compounds mimmicking the phenolic composition of the leachate A. Toxicity of these 3 samples was analyzed using two photobacterial test (BioTox and Microtox), Daphnia test (DAPHTOXKIT F pulex) and rotifiers' test (ROTOXKIT F). All the LC50 values were in the range of 1-10%, leachate A being the most toxic. The growth and detoxifying potential (toxicity of the growth medium was measured using photobacterial tests) of 3 different phenol-utilizing bacteria and acclimated activated sludges was studied in shake-flask cultures. 30% leachate A (altogether 0.6 mM total phenolic compounds) was too toxic to rhodococci and they did not grow. Cell number of Kurthia sp. and Pseudomonas sp. in 30% leachate A increased by 2 orders of magnitude but despite of the growth of bacteria the toxicity of the leachate did not decrease even by 7 weeks of cultivation. However, if the activated sludge was used instead of pure bacterial cultures the toxicity of the 30% leachate A was eliminated already after 3 days of incubation. 30% samples B and C were detoxified by activated sludge even more rapidly, within 2 days. As the biodegradable part of samples A and B should be identical, the detoxification of leachate A compared to that of sample B was most probably inhibited by inorganic (e.g. sulphuric) compounds present in the leachate A. Also, the presence of toxic recalcitrant organic compounds in the leachate A (missed by chemical analysis) that were not readily biodegradable even by activated sludge consortium should not be excluded.


Asunto(s)
Fenoles/metabolismo , Photobacterium/metabolismo , Aguas del Alcantarillado/microbiología , Adenosina Trifosfato/análisis , Animales , Biodegradación Ambiental , Recuento de Colonia Microbiana , Daphnia/efectos de los fármacos , Estonia , Combustibles Fósiles , Fenoles/análisis , Fenoles/toxicidad , Photobacterium/efectos de los fármacos , Proteus/metabolismo , Pseudomonas/metabolismo , Rhodococcus/metabolismo , Rotíferos/efectos de los fármacos , Aguas del Alcantarillado/química , Pruebas de Toxicidad , Administración de Residuos
11.
Clin Cancer Res ; 2(6): 963-72, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9816257

RESUMEN

We aimed to determine the maximum tolerated dose (MTD) of 131I-labeled 81C6 in patients with leptomeningeal neoplasms or brain tumor resection cavities with subarachnoid communication and to identify any objective responses. 81C6 is a murine IgG monoclonal antibody that reacts with tenascin in gliomas/carcinomas but does not react with normal adult brain. 131I-labeled 81C6 delivers intrathecal (IT) radiation to these neoplasms. This study was a Phase I trial in which patients were treated with a single IT dose of 131I-labeled 81C6. Cohorts of three to six patients were treated with escalating doses of 131I (starting dose, 40 mCi; 20 mCi escalations) on 10 mg 81C6. MTD is defined as the highest dose resulting in serious toxicity in no more than two of six patients. Serious toxicity is defined as grade III/IV nonhematological toxicity or major hematological toxicity. We treated 31 patients (8 pediatric and 23 adult). Eighteen had glioblastoma multiforme. Patients were treated with 131I doses from 40 to 100 mCi. Hematological toxicity was dose limiting and correlated with the administered 131I dose. No grade III/IV nonhematological toxicities were encountered. A partial response occurred in 1 patient and disease stabilization occurred in 13 (42%) of 31 patients. Twelve patients are alive (median follow-up, > 320 days); five are progression free >409 days median posttreatment. The MTD of a single IT administration of 131I-labeled 81C6 in adults is 80 mCi 131I-labeled 81C6. The MTD in pediatric patients was not reached at 131I doses up to 40 mCi normalized for body surface area.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Neoplasias Encefálicas/radioterapia , Radioisótopos de Yodo/uso terapéutico , Neoplasias Meníngeas/radioterapia , Radioinmunoterapia , Adolescente , Adulto , Anciano , Animales , Anticuerpos Monoclonales/inmunología , Neoplasias Encefálicas/mortalidad , Preescolar , Femenino , Humanos , Masculino , Neoplasias Meníngeas/mortalidad , Ratones , Persona de Mediana Edad , Radioinmunoterapia/efectos adversos , Dosificación Radioterapéutica
14.
J Clin Oncol ; 12(2): 306-11, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8113837

RESUMEN

PURPOSE: This study was intended to assess the ability of restaging gallium scanning to distinguish between patients with residual radiographic abnormalities who still have active Hodgkin's disease (HD) and those who are truly complete responders. Early identification of the former patients might increase the success of secondary salvage therapy. MATERIALS AND METHODS: The charts of all patients with advanced HD treated at Duke University Medical Center during the years 1983 to 1991 who underwent gallium scanning were reviewed. Thirty-three patients were identified who had gallium scans performed as part of restaging following induction combination chemotherapy; no patient had other signs or symptoms of active or progressive HD. RESULTS: Thirteen of 33 patients had positive restaging gallium scans; 20 patients had negative scans. The 4-year actuarial relapse-free survival (RFS) rate was 75% for patients with negative restaging gallium scans compared with 8% for those with positive restaging scans (P < .001). The 4-year actuarial overall survival (OS) rate was 100% for those with negative scans compared with 51% for gallium-positive patients (P = .001). Twenty-four patients had residual chest x-ray or computed tomographic scan abnormalities. Calculated negative and positive predictive values for gallium scanning are 92% and 90%, respectively, compared with values of 48% and 83% for computed tomographic scanning. CONCLUSION: Restaging gallium scans separate complete responders from induction failures with a high degree of accuracy. Gallium scanning is clearly superior to computed tomography in this regard. Patients with advanced HD who have positive restaging gallium scans after induction chemotherapy should be classified as induction failures and are highly unlikely to be cured with involved-field low-dose radiotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Radioisótopos de Galio , Enfermedad de Hodgkin/diagnóstico por imagen , Análisis Actuarial , Adolescente , Adulto , Femenino , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Cintigrafía , Inducción de Remisión , Estudios Retrospectivos , Análisis de Supervivencia
15.
Ann Anat ; 174(3): 201-6, 1992 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-1503238

RESUMEN

There are four types of cavities of the lumbosacral joints. Type A: The synovial membrane is all around attached to the margin of the articular facet of the superior articular process of the sacrum. Type B: The synovial membrane extends to the posterior surface of the sacrum forming a recess at the root of the superior articular process; this recess communicates widely with the cavity of the joint. Type C: The synovial membrane also forms a recess similar to that of type B, but the gap of communication is narrowed by a fibro-adipose meniscoid. Type D: The synovial membrane is attached in the same way as described in type A; besides a synovial bursa non communicating with the cavity is found at the root of the superior articular process. We have found 43% showing type A, 33% type B, 16% type C and 8% type D. The recesses and bursae described above enable the inferior articular process of the fifth lumbar vertebra to slide at the posterior surface of the sacrum, thus avoiding a painful rubbing during dorsiflexion of the lumbar spine. The existence of these sliding facilities does not depend on the range of the lumbosacral angle nor on the quality of the lumbosacral intervertebral disc.


Asunto(s)
Bolsa Sinovial/anatomía & histología , Articulaciones/anatomía & histología , Vértebras Lumbares/anatomía & histología , Sacro/anatomía & histología , Membrana Sinovial/anatomía & histología , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad
16.
Clin Nucl Med ; 12(1): 22-6, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3028690

RESUMEN

Alpha-aminoisobutyric acid (AIB), a synthetic, nonmetabolized amino acid which is rapidly transported into viable cells by the A-type or alanine-preferring amino acid transport system, has been labeled with the short-lived, positron-emitting radionuclide carbon-11. Carbon-11 labeled AIB is currently being evaluated as a tumor imaging agent for in vivo amino acid transport studies in patients with cancer. In this study, C-11 AIB was used to image two patients with malignant fibrous histiocytoma (MFH), a pleomorphic sarcoma. Following intravenous administration of C-11 AIB, tumors in the distal femur of one patient and in the anterior chest wall of another patient were well visualized using high energy gamma scintigraphy. Since therapy may alter the accumulation of amino acids in tumor tissue, studies using C-11 AIB in patients with MFH before and after chemotherapy are in progress.


Asunto(s)
Ácidos Aminoisobutíricos , Radioisótopos de Carbono , Histiocitoma Fibroso Benigno/diagnóstico por imagen , Adulto , Femenino , Neoplasias Femorales/diagnóstico por imagen , Radioisótopos de Galio , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía , Medronato de Tecnecio Tc 99m , Neoplasias Torácicas/diagnóstico por imagen
17.
Am J Physiol Imaging ; 1(4): 195-200, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3482783

RESUMEN

The work described herein is the first reported use of nitrogen-13-labeled L-methionine in human subjects. Three volunteers and 14 patients with a variety of solid tumors were scanned after intravenous administration of L-(N-13) methionine. In both volunteers and cancer patients, uptake of label was seen in the liver and pancreas, with smaller amounts of label detected in the heart, urinary bladder, and salivary glands. Concentration of N-13 in tumor was seen in 12 of the 14 cancer patients. Five had repeat studies after chemotherapy; in each case, the change in tumor uptake of N-13 after N-13 methionine injection paralleled the clinical response to chemotherapy. Three patients had L-(N-13) glutamate scans the same day that they were studied with N-13 methionine. Concentration of the radiolabel in the tumor was very similar for the two compounds in each case. The systemic distribution of N-13 from methionine is similar to that from glutamate, except for a much smaller myocardial uptake and a prominent accumulation in the intestinal region. It is concluded that L-(N-13) methionine is potentially useful as a biologically significant agent for tumor visualization and assessment of therapeutic response.


Asunto(s)
Metionina , Neoplasias/diagnóstico por imagen , Radioisótopos de Nitrógeno , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Metionina/farmacocinética , Persona de Mediana Edad , Osteosarcoma/diagnóstico por imagen , Cintigrafía , Sarcoma/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Distribución Tisular
18.
Am J Dis Child ; 138(8): 746-8, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6741890

RESUMEN

The diagnosis of idiopathic pulmonary hemosiderosis (IPH) may be elusive. A 6-year-old boy had microcytic hypochromic anemia and a hemolytic component. Hemosiderin-laden macrophages were not found in the gastric aspirate. He had no pulmonary signs or symptoms. Extensive hematologic and roentgenologic investigations failed to reveal the cause of the anemia. Quantitative serial scintigraphic scanning showed significant (35%) pulmonary sequestration of autologous erythrocytes labeled with sodium chromate Cr51. The half-life of the RBCs was moderately decreased (half-life, 15 days; normal, 25 to 35 days). An open-lung biopsy specimen confirmed the diagnosis of IPH. A diagnosis of IPH should be considered when children have iron deficiency anemia and pulmonary signs or symptoms. Organ sequestration studies may be helpful in equivocal cases.


Asunto(s)
Radioisótopos de Cromo , Hemosiderosis/diagnóstico por imagen , Enfermedades Pulmonares/diagnóstico por imagen , Compuestos de Sodio , Anemia Hipocrómica/sangre , Anemia Hipocrómica/complicaciones , Niño , Cromatos , Humanos , Masculino , Cintigrafía
20.
Cancer ; 52(12): 2256-60, 1983 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-6685568

RESUMEN

Previous studies regarding sites of platelet destruction in patients with the Kasabach-Merritt syndrome are conflicting. The authors recently studied an adult patient with multiple large hemangiomata, thrombocytopenia, and intravascular coagulation by external imaging following the injection of autologous Indium-111 labeled platelets. Sequential images showed prompt accumulation of platelet-associated radioactivity in areas within the right hemithorax which corresponded to certain tumors noted on the chest roentgenogram. Despite the presence of multiple other lesions in bone and soft tissues, platelet radioactivity was otherwise normally confined to liver and spleen. Using data obtained from serial images, it was shown that radioactivity within the thoracic masses actually increased over time. These data indicate that platelet consumption occurred as an active process and that localization was not a result of tumor vascularity. It is concluded that platelets are locally consumed within certain hemangiomata. However, within the same individual, there may exist considerable heterogeneity among these tumors with respect to platelet-trapping ability. In similar patients with multiple tumors, indium-platelet scanning might be used to direct local therapy to particular lesions in an effort to correct the thrombocytopenia.


Asunto(s)
Hemangioma/diagnóstico por imagen , Púrpura Trombocitopénica/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Abdomen/diagnóstico por imagen , Adulto , Plaquetas , Huesos/diagnóstico por imagen , Femenino , Humanos , Indio/metabolismo , Radioisótopos , Cintigrafía , Bazo/diagnóstico por imagen , Síndrome , Tórax/diagnóstico por imagen
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