61 research outputs found
DOTATOC: A powerful new tool for receptor-mediated radionuclide therapy
This study presents the first successful use of a peptidic vector, DOTATOC, labelled with the ÎČ-emitting radioisotope yttrium-90, for the treatment of a patient with somatostatin receptor-positive abdominal metastases of a neuroendocrine carcinoma of unknown localization. Tumour response and symptomatic relief were achieved. In addition, the new substance DOTA-TOC was labelled with the diagnostic chemical analogue indium-111 and studied in three patients with histopathologically verified neuroendocrine abdominal tumours for its diagnostic sensitivity and compared with the commercially available OctreoScan. In all patients the kidney-to-tumour uptake ratio (in counts per pixel) was on average 1.9-fold lower with111In-DOTATOC than with OctreoScan. DOTATOC could be a potential new diagnostic and therapeutic agent in the management of neuroendocrine tumour
Peptide receptor radiotherapy: a new option for the management of aggressive fibromatosis on behalf of the Italian Sarcoma Group
The management of aggressive fibromatosis (AF) is problematic, and few options are available to patients unsuitable for surgery and resistant to external-beam radiation therapy (EBRT). We report on two patients with fast-growing recurrences of AF resistant to EBRT who obtained protracted clinical benefits with 90Y-DOTATOC. 90Y-DOTATOC should be further investigated in this setting
PET imaging of αvÎČ3 integrin expression in tumours with 68Ga-labelled mono-, di- and tetrameric RGD peptides
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97195.pdf (publisher's version ) (Closed access)PURPOSE: Due to the restricted expression of alpha(v)beta(3) in tumours, alpha(v)beta(3) is considered a suitable receptor for tumour targeting. In this study the alpha(v)beta(3)-binding characteristics of (68)Ga-labelled monomeric, dimeric and tetrameric RGD peptides were determined and compared with their (111)In-labelled counterparts. METHODS: A monomeric (E-c(RGDfK)), a dimeric (E-[c(RGDfK)](2)) and a tetrameric (E{E[c(RGDfK)](2)}(2)) RGD peptide were synthesised, conjugated with DOTA and radiolabelled with (68)Ga. In vitro alpha(v)beta(3)-binding characteristics were determined in a competitive binding assay. In vivo alpha(v)beta(3)-targeting characteristics of the compounds were assessed in mice with subcutaneously growing SK-RC-52 xenografts. In addition, microPET images were acquired using a microPET/CT scanner. RESULTS: The IC(50) values for the Ga(III)-labelled DOTA-E-c(RGDfK), DOTA-E-[c(RGDfK)](2) and DOTA-E{E[c(RGDfK)](2)}(2) were 23.9 +/- 1.22, 8.99 +/- 1.20 and 1.74 +/- 1.18 nM, respectively, and were similar to those of the In(III)-labelled mono-, di- and tetrameric RGD peptides (26.6 +/- 1.15, 3.34 +/- 1.16 and 1.80 +/- 1.37 nM, respectively). At 2 h post-injection, tumour uptake of the (68)Ga-labelled mono-, di- and tetrameric RGD peptides (3.30 +/- 0.30, 5.24 +/- 0.27 and 7.11 +/- 0.67%ID/g, respectively) was comparable to that of their (111)In-labelled counterparts (2.70 +/- 0.29, 5.61 +/- 0.85 and 7.32 +/- 2.45%ID/g, respectively). PET scans were in line with the biodistribution data. On all PET scans, the tumour could be clearly visualised. CONCLUSION: The integrin affinity and the tumour uptake followed the order of DOTA-tetramer > DOTA-dimer > DOTA-monomer. The (68)Ga-labelled tetrameric RGD peptide has excellent characteristics for imaging of alpha(v)beta(3) expression with PET
Somatostatin analogues in the treatment of gastroenteropancreatic neuroendocrine tumours, current aspects and new perspectives
Gastroenteropancreatic neuroendocrine tumours (GEP NETs) are rare tumours that present many clinical features
Synthesis, structure and characterisation of amido derivatives of [9]aneN3 (1,4,7-triazacyclononane)
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Effectiveness of the Heavy Ion Radiation Criterion as an index of accelerator radiation levels
The research program of the Physics Division's tandem Van de Graaff accelerator facility at Argonne National Laboratory often requires entries into a target room while the accelerator beam is present, both to perform adjustments on an experiment in progress and to set up a future experiment on another beam line. To assure the safety of personnel, while permitting the maximum feasible freedom of movement, it is useful to have a means of predicting the maximum possible radiation levels in the target room for the planned operating conditions. This would assure thorough radiation surveys, by Health Physics personnel, when they are needed, while minimizing delays for low hazard experiments. Such a predictive index has been developed by John P. Schiffer, a Senior Physicist, at Argonne National Laboratory. It is called the Heavy Ion Radiation Criterion (HIRC). The authors have performed an empirical study of the effectiveness of the HIRC. From July, 1978 to May, 1979, the actual, measured radiation levels for accelerator experiments were compared with the calculated HIRC values. For each experiment, the radiation level used was the maximum measured dose equivalent rate (gamma plus neutron), in mrem/h. The results of these measurements are given
A generic system for the Escherichia coli cell-surface display of lipolytic enzymes
EstA is an outer membrane-anchored esterase from Pseudomonas aeruginosa. An inactive EstA variant was used as an anchoring motif for the Escherichia coli cell-surface display of lipolytic enzymes. Flow cytometry analysis and measurement of lipase activity revealed that Bacillus subtilis lipase LipA, Fusarium solani pisi cutinase and one of the largest lipases presently known, namely Serratia marcescens lipase were all efficiently exported by the EstA autotransporter and also retained their lipolytic activities upon cell surface exposition. EstA provides a useful tool for surface display of lipases including variant libraries generated by directed evolution thereby enabling the identification of novel enzymes with interesting biological and biotechnological ramifications. (C) 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved
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