RESUMO
BACKGROUND: The purpose of this study was to investigate whether phosphorus-31 magnetic resonance spectroscopy (31P-MRS) of the isolated donor liver can serve as a viability indicator with prognostic value for transplantation outcome. METHODS: Forty human donor livers preserved with University of Wisconsin solution were studied shortly before transplantation. The respective spectral peak areas of the isolated donor liver were correlated with the amount of hepatocellular graft damage and liver metabolic function shortly after implantation. RESULTS: The individual phosphomonoesters, inorganic phosphate, phosphodiesters, and nicotine adenine dinucleotide peaks were not prognostic for postoperative hepatocellular damage or liver metabolic capacity. The presence of adenosine triphosphate, however, predicts a significantly better metabolic capacity to eliminate bilirubin, to synthesize fibrinogen and antithrombin III, and to maintain a better prothrombin time after transplantation. Furthermore, this study is probably the first 31P-MRS demonstration in the human liver of phosphocreatine. CONCLUSIONS: In the clinical setting described, metabolic assessment using 31P-MRS did not result in a reliable noninvasive test to predict primary graft dysfunction. Study of the role of phosphocreatine in liver metabolism during cold storage is needed.
Assuntos
Fígado/metabolismo , Doadores de Tecidos , Nucleotídeos de Adenina/fisiologia , Sobrevivência Celular , Seguimentos , Humanos , Fígado/química , Fígado/citologia , Transplante de Fígado/fisiologia , Espectroscopia de Ressonância Magnética , Fósforo , Prognóstico , Análise de Regressão , Fatores de TempoRESUMO
During cold preservation for transplantation the tissue hydration state changes. It is not known whether such changes lead to altered relaxation times of 31P nuclei with potential consequences for the quantification of tissue metabolites. Therefore, 31P spectroscopic and proton T1 relaxometric measurements were performed on 42 isolated human donor livers shortly before implantation. The results demonstrate that 31P T1 relaxation times change during preservation for clinical transplantation, thus quantification of tissue metabolites in cold stored donor livers may be in part dependent on the tissue hydration state. Furthermore, it appeared that changes in tissue hydration state especially affect the physico-chemical characteristics of the intracellular fluid compartment. This study indicates that reliable spectroscopic quantification of tissue metabolites, particularly during sequential spectroscopic measurements in cold stored donor organs is best warranted under fully relaxed conditions.
Assuntos
Criopreservação , Transplante de Fígado , Fígado/metabolismo , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Soluções para Preservação de Órgãos , Fósforo/metabolismo , Adenosina/administração & dosagem , Alopurinol/administração & dosagem , Aorta , Área Sob a Curva , Sistema Biliar , Água Corporal/metabolismo , Fenômenos Químicos , Físico-Química , Análise de Fourier , Glutationa/administração & dosagem , Artéria Hepática , Humanos , Processamento de Imagem Assistida por Computador , Insulina/administração & dosagem , Líquido Intracelular/metabolismo , Transplante de Fígado/fisiologia , Preservação de Órgãos , Isótopos de Fósforo , Veia Porta , Rafinose/administração & dosagem , Reprodutibilidade dos Testes , Análise EspectralRESUMO
Proton magnetic resonance spectroscopic imaging (1H-MRSI) and positron emission tomography with the tracer L-[1-11C]tyrosine (11C-TYR) were used to localize gliomas for biopsy or resection. This is especially helpful in cases of low-grade gliomas, if these lesions are not visualized by contrast-enhanced computed tomographic and magnetic resonance imaging scans. The clues to improved localization are provided by changes in tissue metabolite contents, such as elevation of phosphocholine, indicating cellular proliferation; decrease of N-acetylaspartate, denoting loss of neurons (as these are replaced by tumor cells); and elevation of lactate, pointing to the prevalence of glycolysis, as observed in many tumors. These data on tissue metabolite content have been obtained in vivo in the patient by proton magnetic resonance spectroscopy; metabolite maps derived from these data then visualize the distribution of the various metabolites over the section of the brain under investigation. Alternatively, localization of a tumor may be achieved by means of positron emission tomography depicting the pattern of uptake of the amino acid tracer 11C-TYR, as it tends to be incorporated in the process of cellular proliferation and protein biosynthesis. Five cases are presented as examples.
Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada de Emissão , Adulto , Astrocitoma/patologia , Astrocitoma/cirurgia , Biópsia , Neoplasias Encefálicas/cirurgia , Radioisótopos de Carbono , Craniotomia , Feminino , Lobo Frontal/patologia , Lobo Frontal/cirurgia , Glioblastoma/patologia , Glioblastoma/cirurgia , Glioma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas Estereotáxicas , Lobo Temporal/patologia , Lobo Temporal/cirurgia , TirosinaAssuntos
Transplante de Fígado/patologia , Fígado/patologia , Espectroscopia de Ressonância Magnética , Soluções para Preservação de Órgãos , Nucleotídeos de Adenina/análise , Adenosina , Monofosfato de Adenosina/análise , Trifosfato de Adenosina/análise , Alopurinol , Ésteres/análise , Glutationa , Humanos , Insulina , Fígado/química , Fígado/metabolismo , NAD/análise , Preservação de Órgãos , Fósforo , Rafinose , Soluções , Doadores de TecidosRESUMO
31P Magnetic Resonance-Spectroscopy was performed at the site of tender points in the trapezius muscle of patients with primary fibromyalgia syndrome. Earlier, in vitro studies have reported changes in the high energy phosphate-metabolism in biopsies taken from tender points of fibromyalgia patients. The observed alterations could not be confirmed with in vivo Magnetic Resonance-Spectroscopy.