English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Objectives  Receptor scintigraphy gains more interest for diagnosis and treatment of tumors, in particular for neuroendocrine tumors (NET). We used a pan-Bombesin analog, the peptide DOTA-PEG 2 -[D-tyr 6 , β-Ala 11 , Thi 13 , Nle 14 ] BN(6-14) amide (BZH3). BZH3 binds to at least three receptor subtypes: the BB1 (Neuromedin B), BB2 (Gastrin-releasing peptide, GRP), and BB3. Imaging of ανβ3 integrin expression playing an important role in angiogenesis and metastasis was accomplished with a  68 Ga-RGD tetramer. The purpose of this study was to investigate the kinetics and to compare both tracers in an experimental NET cell line.    Methods  This study comprised nine nude rats inoculated with the pancreatic tumor cell line AR42J. Dynamic positron emission tomography (PET) scans using  68 Ga-BZH3 and  68 Ga-RGD tetramer were performed ( 68 Ga-RGD tetramer:  n  = 4,  68 Ga-BZH3:  n  = 5). Standardized uptake values (SUVs) were calculated, and a two-tissue compartmental learning-machine model (calculation of  K 1 -  k 4 vessel density (VB) and receptor binding potential (RBP)) as well as a non-compartmental model based on the fractal dimension was used for quantitative analysis of both tracers. Multivariate analysis was used to evaluate the kinetic data.    Results  The PET kinetic parameters showed significant differences when individual parameters were compared between groups. Significant differences were found in FD, VB,  K 1, and RBP ( p  = 0.0275, 0.05, 0.05, and 0.0275 respectively). The 56- to 60-min SUV for  68 Ga-BZH3, with a range of 0.86 to 1.29 (median, 1.19) was higher than the corresponding value for the  68 Ga-RGD tetramer, with a range of 0.78 to 1.31 (median, 0.99). Furthermore, FD, VB,  K 1, and RBP for  68 Ga-BZH3 were generally higher than the corresponding values for the  68 Ga-RGD tetramer, whereas  k 3 was slightly higher for  68 Ga-RGD tetramer.    Conclusions  As a parameter that reflects receptor binding, the increase of  K 1 for  68 Ga-BZH3 indicated higher expression of bombesin receptors than that of the ανβ3 integrin in neuroendocrine tumors.  68 Ga-BZH3 seems better suited for diagnosis of NETs owing to higher global tracer uptake.

ejnmmi research

Comparison between 68Ga-bombesin (68Ga-BZH3) and the cRGD tetramer 68Ga-RGD4 studies in an experimental nude rat model with a neuroendocrine pancreatic tumor cell line