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1.
Nuklearmedizin ; 52(6): 212-21, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24036694

RESUMO

OBJECTIVE: Increased amino acid transport in brain tumours is used for diagnostic purposes. It has been shown that the α-emitting radionuclide astatine-211 labeled to L-phenylalanine is taken up by glioblastoma cells. We here tested, if systemic treatment with 4-[211At]astatine-phenylalanine (At-Phe) has a beneficial effect on survival of rats with intracranial glioblastoma. ANIMALS, METHODS: The rat glioblastoma cell line BT4Ca was implanted into the prefrontal cortex of female BDIX rats by stereotaxic microinjection (10,000 cells/3 µl; n = 83). 3 days after implantation At-Phe or phosphate buffered saline were injected intravenously. A third group was treated twice, i.e., on day 3 and 10. Health condition was assessed each day by using a score system. Rats were sacrificed on days 6, 10, 13 and 17 after implantation, or when showing premortal health condition to measure tumour volume and necrosis. The proliferation index (PI) was assessed after immunohistochemical staining of Ki-67. RESULTS: Survival time of rats treated twice with At-Phe was significantly prolonged. Additionally, both At-Phe-treated groups remained significantly longer in a better health condition. Rats with poor health status had larger tumours than rats with fair health condition. Overall, irrespective of treatment the PI was reduced in rats with poor health condition. Necrosis was larger in rats treated twice with At-Phe. CONCLUSION: Intravenous treatment with At-Phe enhanced survival time of rats with intracranial glioblastomas and improved health condition. These results encourage studies using local treatment of intracranial glioblastoma with At-Phe, either by repeated local injection or by intracavital application after tumour resection.


Assuntos
Astato/administração & dosagem , Braquiterapia/métodos , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Fenilalanina/administração & dosagem , Animais , Neoplasias Encefálicas/diagnóstico , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Feminino , Glioblastoma/diagnóstico , Compostos Radiofarmacêuticos/administração & dosagem , Ratos , Taxa de Sobrevida , Resultado do Tratamento
2.
J Agric Saf Health ; 18(2): 141-54, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22655523

RESUMO

Documented incidents have occurred in which failure or unintentional disengagement of agricultural hitch pins has contributed to property damage and personal injury. An examination of current hitch pin use on a convenience sample of farm operations in Indiana revealed a variety of non-standard, worn and damaged, and inappropriately sized hitch pins in use. Informal interviews with the farm operators confirmed that hitch pin misuse, failure, or disengagement is a relatively widespread problem that remains largely unaddressed. On-site observations also suggested a low use of hitch pin retaining devices or safety chains. A review of prior research revealed that little attention has been given to this problem, and currently no documentation allows for an estimate of the frequency or severity of losses associated with hitch pin misuse, failure, or disengagement. No specific engineering standards were found that directly applied to the design, appropriate selection, or loading capacity of agricultural hitch pins. Major suppliers of replacement hitch pins currently provide little or no information on matching hitch pin size to intended applications, and most replacement hitch pins examined were of foreign origin, with the overwhelming majority imported from China or India. These replacement hitch pins provided no specifications other than diameter, length, and, in some cases, labeling that indicated that the pins had been "heat treated. " Testing of a sample of 11 commercially available replacement hitch pins found variation along the length of the pin shaft and between individual pins in surface hardness, a potential predictor of pin failure. Examination of 17 commercially available replacement pins also revealed a variety of identifiers used to describe pin composition and fabrication methods, e.g., "heat treated." None of the pins examined provided any specifications on loading capacity. It was therefore concluded that there is a need to develop an agricultural hitch pin engineering standard that would reflect current agricultural applications and practices and that would be promoted to both original equipment manufacturers and manufacturers and suppliers of replacement hitch pins. The standard should address the design of composite pins, heat treating, surface hardening, loading capacity and labeling of such, incorporation of unintentional disengagement prevention devices, indicators of the need for replacement due to wear, and safety information that should be included in operator instructions. ASABE is the most appropriate organization to develop such a standard. It was also concluded that agricultural safety and health programs and professionals need to raise the awareness of farmers concerning the appropriate selection and use of agricultural hitch pins, including the need to replace non-standard pins with pins less likely to fail or disengage during use, the need to replace hitch pins with indications of potential failure, and the importance of using appropriate safety chains, especially during transport of equipment behind tractors and trucks on public roads.


Assuntos
Agricultura/instrumentação , Engenharia/normas , Acidentes de Trabalho/prevenção & controle , Engenharia/métodos , Desenho de Equipamento/métodos , Desenho de Equipamento/normas , Segurança de Equipamentos/métodos , Segurança de Equipamentos/normas , Humanos , Indiana , Traumatismos Ocupacionais/prevenção & controle , Sociedades Científicas
3.
Nuklearmedizin ; 50(5): 214-20, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21789339

RESUMO

UNLABELLED: The aim of this study is to verify the in vivo stability, to determine the biodistribution and to estimate the unspecific radiotoxicity of an (211)At-labelled CD33-antibody ((211)At-antiCD33) in mice with a view to therapeutic application in treating leukaemia. ANIMALS, METHODS: (211)At was produced via the (209)Bi(a,2n)(211)At reaction and was linked via 3-(211)At-succinimidyl-benzoate to the antiCD33-antibody. The biodistribution and the in vivo stability in serum were determined after i.v.-injection in NMRI nu/nu-mice. For toxicity experiments, mice received either three times 315-650 kBq (211)At-antiCD33 or unlabelled antibody and NaCl-solution respectively. RESULTS: (211)At-antiCD33 showed a characteristic biodistribution complying with the unspecific antibody retention in the reticular endothelial system. The largest proportion of radioactivity remained in blood and blood-rich tissues with a minor accumulation in the thyroid and stomach. After 21 h, >85% of activity in serum still represented intact antibody. Mice showed no difference in unspecific toxicity of (211)At-labelled antibodies over six months compared to those treated with unlabelled antibody and NaCl-solution respectively, with regard to histopathologic lesions, survival time, behaviour and haemograms. CONCLUSION: The radiolabelling method yielded adequate in vivo stability of (211)At-antiCD33. Biodistribution with rapid elimination of free (211)At via kidneys and urine complies with requirements for targeted therapy. Activity doses potentially required for treatment do not elicit radiotoxicity to normal organs in mice. Further development is required to enhance the apparent specific activity and to verify the efficacy in an adequate animal model before phase I clinical studies in leukaemia can be envisaged.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Astato/farmacocinética , Astato/toxicidade , Lesões por Radiação/etiologia , Animais , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/toxicidade , Antígenos CD/toxicidade , Antígenos de Diferenciação Mielomonocítica/toxicidade , Células HL-60 , Humanos , Taxa de Depuração Metabólica , Camundongos , Camundongos Nus , Especificidade de Órgãos , Doses de Radiação , Lesões por Radiação/diagnóstico , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/toxicidade , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Taxa de Sobrevida , Distribuição Tecidual
4.
Nuklearmedizin ; 48(6): 215-20, 2009.
Artigo em Alemão | MEDLINE | ID: mdl-19902120

RESUMO

This guideline is a prerequisite for the quality management in the treatment of non-Hodgkon-lymphomas in patients with relapsed or refractory follicular lymphoma after rituximab therapy and as consolidation therapy after first remission following CHOP like treatment using radioimmunotherapy. It is based on an interdisciplinary consensus and contains background information and definitions as well as specified indications and detailed contraindications of treatment. Essential topics are the requirements for institutions performing the therapy. For instance, presence of an expert for medical physics, intense cooperation with all colleagues committed to treatment of lymphomas, and a certificate of instruction in radiochemical labelling and quality control are required. Furthermore, it is specified which patient data have to be available prior to performance of therapy and how treatment has to be carried out technically. Here, quality control and documentation of labelling are of great importance. After treatment, clinical quality control is mandatory (work-up of therapy data and follow-up of patients). Essential elements of follow-up are specified in detail. The complete treatment inclusive after-care has to be realised in close cooperation with those colleagues (hemato-oncologists) who propose, in general, radioimmunotherapy under consideration of the development of the disease.


Assuntos
Antígenos CD2/imunologia , Linfoma de Células B/imunologia , Linfoma de Células B/radioterapia , Medicina Nuclear/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Radioterapia (Especialidade)/normas , Radioimunoterapia/normas , Alemanha , Humanos
5.
Zentralbl Chir ; 133(3): 267-84, 2008 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-18563694

RESUMO

In this review, standards of diagnosis and treatment of colorectal liver metastases are described on the basis of a workshop discussion. Algorithms of care for patients with synchronous / metachronous colorectal liver metastases or locoregional recurrent tumour are presented. Surgical resection is the procedure of choice in the curative treatment of liver metastases. The decision about the resection of liver metastases should consider the following parameters: 1. General operability of the patient (comorbidity); 2. Achievability of an R 0 situation: i. if necessary, in combination with ablative methods, ii. if necessary, neoadjuvant chemotherapy, iii. the ability to eradicate extrahepatic tumour manifestations; 3. Sufficient volume of the liver remaining after resection ("future liver remnant = FLR): i. if necessary, in combination with portal vein embolisation or two-stage hepatectomy; 4. The feasibility to preserve two contiguous hepatic segments with adequate vascular inflow and outflow as well as biliary drainage; 5. Tumour biological aspects ("prognostic variables"); 6. Experience of the surgeon and centre! Extrahepatic disease does not contraindicate hepatectomy for colorectal liver metastases provided a complete resection of both intra- and extrahepatic disease is feasible. Even in bilobar colorectal metastases and 5 or more tumours in the liver, a complete tumour resection has been described. The type of resection (hepatic wedge resection or anatomic resection) does not influence the recurrence rate. Preoperative volumetry is indicated when major hepatic resection is planned. The FLR should be 25 % in patients with normal liver, 40 % in patients who have received intensive chemotherapy or in cases of fatty liver, liver fibrosis or diabetes, and 50-60 % in patients with cirrhosis. In patients with initially unresectable colorectal liver metastases, preoperative chemotherapy enables complete resection in 15-30 % of the cases, whereas the value of neoadjuvant chemotherapy in patients with resectable liver metastases has not been sufficiently supported. In situ ablative procedures (radiofrequency ablation = RFA and laser-induced interstitial thermotherapy = LITT) are local therapy options in selected patients who are not candidates for resection (central recurrent liver metastases, bilobar multiple metastases and high-risk resection or restricted patient operability). Patients with tumours larger than 3 cm have a high local recurrence rate after percutaneous RFA and are not optimal candidates for this procedure. The physician's experience influences the results significantly, both after hepatectomy and after in situ ablation. Therefore, patients with colorectal liver metastases should be treated in centres with experience in liver surgery.


Assuntos
Neoplasias Colorretais/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/secundário , Recidiva Local de Neoplasia/cirurgia , Algoritmos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Terapia Combinada , Intervalo Livre de Doença , Embolização Terapêutica , Medicina Baseada em Evidências , Estudos de Viabilidade , Humanos , Laparoscopia , Fígado/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Metástase Linfática/patologia , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/mortalidade , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Prognóstico
7.
Cochrane Database Syst Rev ; (3): CD003023, 2007 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-17636713

RESUMO

BACKGROUND: The consumption of psychostimulants for non-medical reasons probably occurs because of their euphoriant and psychomotor-stimulating properties. Chronic consumption of these agents results in development of stereotyped behaviour, paranoia, and possibly aggressive behaviour. Psychosocial treatments for psychostimulant use disorder are supposed to improve compliance, and to promote abstinence. Evidence from randomised controlled trials in this subject needs to be summarised. OBJECTIVES: To conduct a systematic review of all RCTs on psychosocial interventions for treating psychostimulant use disorder. SEARCH STRATEGY: Electronic searches of Cochrane Library, EMBASE, MEDLINE, and LILACS (to may 2006); reference searching; personal communication; conference abstracts; unpublished trials from pharmaceutical industry; book chapters on treatment of psychostimulants abuse/ dependence. SELECTION CRITERIA: All randomised-controlled trials focusing on psychosocial interventions for treating psychostimulants abuse/ dependence. DATA COLLECTION AND ANALYSIS: Three authors extracted the data independently and Relative Risks, weighted mean difference and number needed to treat were estimated, when possible. The reviewers assumed that people who died or dropped out had no improvement (intention to treat analysis) and tested the sensitivity of the final results to this assumption. MAIN RESULTS: Twenty-seven randomised controlled studies (3663 participants) fulfilled inclusion criteria and had data that could be used for at least one of the main comparisons. There was a wide heterogeneity in the interventions evaluated: this did not allow to provide a summary estimate of effect and results cannot be summarised in a clear cut way. The comparisons between different type of Behavioural Interventions showed results in favour of treatments with some form of Contingency management in respect to both reducing drop outs and lowering cocaine use.. AUTHORS' CONCLUSIONS: Overall this review reports little significant behavioural changes with reductions in rates of drug consumption following an intervention. Moreover, with the evidence currently available, there are no data supporting a single treatment approach that is able to comprise the multidimensional facets of addiction patterns and to significantly yield better outcomes to resolve the chronic, relapsing nature of addiction, with all its correlates and consequences.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/terapia , Transtornos Relacionados ao Uso de Cocaína/terapia , Psicoterapia/métodos , Adaptação Psicológica , Adulto , Idoso , Transtornos Relacionados ao Uso de Anfetaminas/psicologia , Transtornos Relacionados ao Uso de Cocaína/psicologia , Terapia Cognitivo-Comportamental/métodos , Aconselhamento/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reforço Psicológico , Prevenção Secundária , Resultado do Tratamento
8.
Eur J Nucl Med Mol Imaging ; 34(11): 1861-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17492446

RESUMO

PURPOSE: The transplantation of lymph node fragments and stimulation of lymph vessel regeneration seems to be a promising model to prevent lymphoedema in patients after mammary tumour excision combined with axillary lymph node dissection and irradiation. This study evaluated the advantages of SPECT-CT in studying the regeneration of lymph vessels and lymphoid tissue after autologous lymph node transplantation. METHODS: Five minipigs underwent autologous lymph node transplantation in the left groin. The lymph node was excised, cut into six pieces and embedded into two newly created subcutaneous pouches on this side. The superficial lymph node of the right groin was removed as a control. Five months after surgery the lymph flow of both legs was investigated using conventional lymphoscintigraphy and SPECT-CT with 10 MBq(99m)Tc-nanocolloid in combination with Berlin Blue injected subcutaneously into the draining area. RESULTS: The integration of the transplanted lymph node fragments was shown. The SPECT-CT results correlated with the in situ findings observed at dissection. Afferent and efferent lymph flow could be followed up to the lumbar trunks. The use of SPECT-CT allowed exact localisation of the lymph node fragments in three-dimensional space and the regeneration of the lymph node fragments was documented histologically. CONCLUSION: SPECT-CT is a good method to evaluate lymphatic flow and document lymph node regeneration. The data suggest that autologous lymph node transplantation is a promising model for prevention of lymphoedema.


Assuntos
Sobrevivência de Enxerto , Linfonodos , Regeneração , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Animais , Linfonodos/diagnóstico por imagem , Linfonodos/transplante , Suínos , Porco Miniatura
9.
Eur J Radiol ; 63(3): 427-35, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17293073

RESUMO

Post transplant lymphoproliferative disease (PTLD) is a severe complication after solid organ or bone marrow transplantation. In pediatric transplant recipients PTLD is the most common malignancy. The aim of this study was to evaluate a possible role for positron emission tomography with [18F]-2-fluoro-2-desoxy-glucose (FDG) in the initial staging and in therapy monitoring of pediatric patients suffering from biopsy-proven CD20-positive PTLD after solid organ transplantation. Seven pediatric patients were included. All available imaging studies - CT (n=15), MRI (n=16) and PET/PETCT (n=16) - were reviewed on a lesion by lesion base. The performance of FDG-PET in the initial staging and during therapy with a chimeric anti-CD20 antibody was compared to conventional cross sectional imaging and correlated with the clinical outcome. FDG-PET identified all sites of disease as shown by CT/MRI and helped to clarify the significance of equivocal findings. The initial stage of disease was correctly identified by FDG-PET alone when compared to CT/MRI. During therapy, FDG-PET was superior to conventional cross-sectional imaging in the early evaluation of response.


Assuntos
Fluordesoxiglucose F18 , Transtornos Linfoproliferativos/diagnóstico por imagem , Transplante de Órgãos , Tomografia por Emissão de Pósitrons/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Compostos Radiofarmacêuticos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Transtornos Linfoproliferativos/etiologia , Masculino , Estudos Retrospectivos
11.
Appl Radiat Isot ; 64(7): 763-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16554168

RESUMO

A synthesis of 1-(2,4-dichlorophenyl)-5-(4-[123I]iodophenyl)-4-methyl-1H-pyrazole-3-carboxylic acid N',N'-dimethyl-hydrazide ([123I]Me2Pyr), a new radioiodinated analogue of the high-affinity cannabinoid CB1 receptor antagonist SR141716A, is described. Labelling was achieved by radioiododestannylation of the tributylstannyl precursor with [123I]iodide in the presence of chloramine T. HPLC purification afforded the labelled product in 48% radiochemical yield. Preliminary rat brain biodistribution studies with the 125I labelled compound revealed high uptake in the substantia nigra, the globus pallidus externus and the cerebellum, which is consistent with the known distribution of CB1 receptors.


Assuntos
Radioisótopos do Iodo/química , Pirazóis/síntese química , Compostos Radiofarmacêuticos/síntese química , Receptor CB1 de Canabinoide/análise , Animais , Autorradiografia , Hidrazinas/química , Hidrazinas/farmacocinética , Hidrazinas/farmacologia , Marcação por Isótopo/métodos , Espectroscopia de Ressonância Magnética , Piperidinas/química , Piperidinas/farmacologia , Pirazóis/química , Pirazóis/farmacocinética , Pirazóis/farmacologia , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/metabolismo , Rimonabanto , Espectrometria de Massas por Ionização por Electrospray , Substância Negra/metabolismo
15.
Urologe A ; 43(11): 1397-409, 2004 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-15502907

RESUMO

Positron emission tomography (PET) using ((18)F)2-fluoro-D-2-desoxyglucose (FDG) has been shown to be a highly sensitive and specific imaging modality in the diagnosis of primary and recurrent tumors and in the control of therapies in numerous non-urologic cancers. It was the aim of this review to validate the significance of PET as a diagnostic tool in malignant tumors of the urogenital tract. A systematic review of the current literature concerning the role of PET for malignant tumors of the kidney, testicles, prostate, and bladder was carried out. The role of FDG PET for renal cell cancer can be seen in the detection of recurrences after definitive local therapy and metastases. The higher sensitivity of PET in comparison to other therapeutic modalities (CT, ultrasound, MRI) in recurrent and metastatic renal cell cancer suggests a supplemental role of this diagnostic procedure to complement other imaging modalities.The clinical value of PET is established for the identification of vital tumor tissue after chemotherapy of seminomatous germ cell tumors. This diagnostic method has little significance for primary tumor staging and diagnosis of non-seminomatous germ cell tumor because of the high probability of false-negative results in adult teratomas. FDG PET is not sensitive enough in the diagnosis of primary or recurrent tumors in prostate or bladder cancer. Also PET did not prove to be superior to conventional bone scintigram in the detection of mostly osteoblastic metastases in prostate cancer. The recent use of alternative tracers, which are partly not eliminated by urinary secretion (acetate, choline) has increased the sensitivity and specificity of PET also in this tumor entity so that further clinical investigations are needed to validate these technical modifications in their significance for this imaging modality. PET appears to be sufficiently evaluated only for the diagnostic follow-up of patients with seminomatous germ cell tumors after chemotherapy to regard it is the diagnostic tool of first choice. For all other tumors of the urogenital tract this proof is still awaited.


Assuntos
Fluordesoxiglucose F18 , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Tomografia por Emissão de Pósitrons/métodos , Neoplasias Urogenitais/diagnóstico por imagem , Urologia/métodos , Algoritmos , Humanos , Tomografia por Emissão de Pósitrons/tendências , Prognóstico , Compostos Radiofarmacêuticos , Neoplasias Urogenitais/terapia , Neoplasias Urológicas/diagnóstico por imagem , Neoplasias Urológicas/terapia , Urologia/tendências
16.
Nuklearmedizin ; 43(5): 171-6, 2004 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-15480506

RESUMO

This guideline is a prerequisite for the quality management in the treatment of non-Hodgkin-lymphomas using radioimmunotherapy. It is based on an interdisciplinary consensus and contains background information and definitions as well as specified indications and detailed contraindications of treatment. Essential topics are the requirements for institutions performing the therapy. For instance, presence of an expert for medical physics, intense cooperation with all colleagues committed to treatment of lymphomas, and a certificate of instruction in radiochemical labelling and quality control are required. Furthermore, it is specified which patient data have to be available prior to performance of therapy and how the treatment has to be carried out technically. Here, quality control and documentation of labelling are of greatest importance. After treatment, clinical quality control is mandatory (work-up of therapy data and follow-up of patients). Essential elements of follow-up are specified in detail. The complete treatment inclusive after-care has to be realised in close cooperation with those colleagues (haematology-oncology) who propose, in general, radioimmunotherapy under consideration of the development of the disease.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD20/sangue , Linfoma de Células B/radioterapia , Linfoma Folicular/radioterapia , Radioimunoterapia/normas , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais Murinos , Antígenos CD/sangue , Humanos , Linfoma de Células B/sangue , Linfoma Folicular/sangue , Controle de Qualidade , Dosagem Radioterapêutica , Rituximab , Distribuição Tecidual
17.
Eur J Nucl Med Mol Imaging ; 31(10): 1405-12, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15278308

RESUMO

PURPOSE: Previous studies have shown high sensitivity of positron emission tomography (PET) with 11C-methionine in the pre-operative localisation of parathyroid adenoma and hyperplasia. Nonetheless, in secondary and tertiary hyperparathyroidism (HPT) and in patients with recurrent disease, pre-operative localisation of adenomatous (PTA) or hyperplastic tissue is still a problem with all available methods. The aim of this study was to define the optimal imaging protocol and to compare the diagnostic value of 11C-methionine PET and 99mTc-methoxyisobutylisonitrile (MIBI) single-photon emission computed tomography (SPECT): in particular, we wished to define the benefit of 11C-methionine in those patients with inconclusive or negative conventional imaging. METHODS: Thirty highly pre-selected patients with HPT were enrolled. Sixteen patients had primary HPT, 12 patients had secondary HPT, and two patients had recurrences of parathyroid carcinomas. All patients had ultrasound of the neck, dual-phase scintigraphy with 99mTc-MIBI and PET with 11C-methionine. SUV(parathyroid)/SUV(cervical soft tissue) (target-to-background) and SUV(parathyroid tissue)/SUV(thyroid tissue) (target-to-non-target) ratios were calculated. After surgery, histology of specimens was obtained in all patients but one. RESULTS: In 12 patients with secondary or tertiary HPT, 36 hyperplastic parathyroid glands were histologically verified. Twenty-five of 36 lesions (69%) were detected with 11C-methionine PET and 17 (47%) with 99mTc-MIBI scintigraphy. PET studies were positive in 17/18 (94%) cases in which HPT was related to adenomas or carcinomas. 99mTc-MIBI scintigraphy/SPECT yielded pathological lesions in 9/18 cases (50%). All eight atypical localisations of parathyroid glands were detected with PET but only six of the eight were detected with 99mTc-MIBI scintigraphy/SPECT. In 10/11 patients with recurrent HPT and non-diagnostic scintigraphy/SPECT, hyperfunctional parathyroid tissue was identified with 11C-methionine PET. The highest SUV(parathyroid)/SUV(cervical soft tissue) ratio was found 10 min, and the highest SUV(parathyroid tissue)/SUV(thyroid tissue) ratio 40 min post injection. In three patients clear delineation of hyperfunctional tissue was only achieved after 40 min post injection. CONCLUSION: 11C-methionine PET is a clinically useful method in highly pre-selected patients with recurrent primary HPT as well as in secondary and tertiary HPT if ultrasound and 99mTc-MIBI SPECT are inconclusive or negative. PET imaging of atypical PTA localisations is more accurate than conventional scintigraphy. In order to achieve optimal contrast of parathyroid glands versus thyroid tissue and adjacent soft tissue, imaging at both 10 min and 40 min is recommended.


Assuntos
Hiperparatireoidismo/diagnóstico por imagem , Hiperparatireoidismo/cirurgia , Metionina , Tomografia por Emissão de Pósitrons/métodos , Cuidados Pré-Operatórios/métodos , Tireoidectomia/métodos , Adulto , Idoso , Feminino , Humanos , Hiperparatireoidismo/diagnóstico , Hiperparatireoidismo Secundário/diagnóstico , Hiperparatireoidismo Secundário/diagnóstico por imagem , Hiperparatireoidismo Secundário/cirurgia , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Eur J Nucl Med Mol Imaging ; 31(8): 1097-104, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15029459

RESUMO

68Ge/68Ga generators provide cyclotron-independent access to positron emission tomography (PET) radiopharmaceuticals. We describe a system which allows the safe and efficient handling of 68Ge/68Ga generator eluates for labelling of DOTA-derivatised peptide ligands. The system comprises concentration and purification of the 68Ga eluate as well as labelling and purification steps for peptides, and can be used with different 68Ge/68Ga generator types. The suitability and efficiency were tested with two different DOTA-derivatised somatostatin derivatives and a DOTA-derivatised bombesin derivative. Amounts of 10-20 nmol of the peptides were sufficient and resulted in labelling yields of 50% for all peptides. The built-in safety precautions have proven to be appropriate in allowing use of the method for routine clinical applications. The system was set up and operated in a "hot lab" by personnel with no previous experience in the preparation of PET radiopharmaceuticals.


Assuntos
Radioisótopos de Gálio/química , Compostos Heterocíclicos com 1 Anel/química , Marcação por Isótopo/instrumentação , Marcação por Isótopo/métodos , Peptídeos/química , Compostos Radiofarmacêuticos/química , Bombesina/análogos & derivados , Bombesina/isolamento & purificação , Radioisótopos de Gálio/isolamento & purificação , Compostos Heterocíclicos com 1 Anel/síntese química , Compostos Heterocíclicos com 1 Anel/isolamento & purificação , Ligantes , Peptídeos/síntese química , Peptídeos/isolamento & purificação , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/isolamento & purificação , Somatostatina/análogos & derivados , Somatostatina/isolamento & purificação , Manejo de Espécimes/instrumentação , Manejo de Espécimes/métodos
19.
Leukemia ; 18(3): 394-400, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14671631

RESUMO

The analysis of CD87 (urokinase-type plasminogen activator receptor - uPAR) expression has a potential role in the diagnostic or prognostic work-up of several hematological malignancies, particularly acute leukemia and multiple myeloma. The distribution of CD87 in acute myeloid leukemia (AML) varies according to the FAB subtype (highest expression in M5 and lowest in M0). Functionally, it is conceivable that the expression of CD87 could contribute to the invasive properties of the leukemic cells towards the skin and mucosal tissues as reflected by the clinical behavior of CD87 high cases. The lack of or weaker expression of CD87 on blast cells from ALL patients supports the concept that CD87 investigation might help in the distinction of AMLs from lymphoid malignancies. Among lymphoproliferative disorders, the expression of CD87 is exclusively found in pathological plasma cells. Since plasma cells also coexpress some adhesion molecules such as CD138 and CD56, this observation is consistent with the capacity of these cells to home in the bone compartment. High levels of soluble uPAR appear to represent an independent factor predicting worse prognosis and extramedullary involvement in multiple myeloma.


Assuntos
Doenças Hematológicas/metabolismo , Ativadores de Plasminogênio/metabolismo , Receptores de Superfície Celular/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Receptores de Ativador de Plasminogênio Tipo Uroquinase
20.
J Biol Regul Homeost Agents ; 18(3-4): 335-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15786701

RESUMO

Lysosomal proteins including myeloperoxidase (MPO), lysozyme (LZ), CD68 and lactoferrin (LF), represent classical immunohistology marker molecules. Additionally, flow cytometry can be used to detect and quantify their expression at the single cell level in phenotypically defined leukocyte subsets. Recent results demonstrated that expression densities of these intracellular proteins vary among myeloid cell subsets, thus enabling insights into novel subset biology and development. Additionally, whole blood staining protocols allow detection of lysosomal proteins in infrequent leukocyte subsets such as circulating CD34+ hematopoietic progenitors and dendritic cells (DC). Thus, information on leukocyte subset distribution and aberrant phenotypes might be gained for diagnositic purposes. Finally, FACS detection of MPO and LZ proved to be of high value for the lineage diagnosis of acute leukemias.


Assuntos
Linhagem da Célula , Citometria de Fluxo , Leucemia Mieloide Aguda/diagnóstico , Leucócitos/classificação , Proteínas/análise , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Biomarcadores , Humanos , Muramidase/análise , Mielopoese , Neoplasia Residual , Peroxidase/análise
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