56 research outputs found

    Radiopharmaceuticals for somatostatin receptor imaging

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    The aim of this review is to summarize the developments and briefly characterize the somatostatin analogs which are currently used for somatostatin receptor imaging in clinical routine or in early phase clinical trials. Somatostatin (sst) receptor targeting with radiolabeled peptides has become an integral part in nuclear oncology during the last 20 years. This integration process has been initiated in Europe with the introduction to the market of 111In-DTPA-DPhe1-octreotide [111In-pentetreotide]. Introducing 99mTc in somatostatin receptor targeting radiopeptides resulted in much better image quality, higher sensitivity of tumor detection and lower mean effective dose for the examined patient. The next generation are 68Ga labeled somatostatin analogs. Due to the spatial resolution of PET technique and increasing number of PET scanners, the PET or PET/CT technique became very important in somatostatin receptor imaging. Until up to a couple of years ago the analogs of somatostatin were constructed aiming at their agonistic behavior, expecting that their internalization with the receptor acti­vated by the radiolabeled ligand and its retention within the tumor cell are crucial for efficient imaging and therapy. Recently it has been shown that the antagonists recognize more binding sites at the tumor cell membrane and hence offer an improved diagnostic efficacy, especially when the density of sst receptors is low. This approach may in future improve diagnostic value of somatostatin receptor imaging techniques. The developments in tracer design are followed by the improvements in imaging techniques. The new SPECT scanners offer resolution close to that of PET, which might open a new era for 99mTc and other SPECT radiotracers

    Glucagon-like peptide-1 receptor imaging with [Lys^{40}(Ahx-HYNIC-^{99m}Tc/EDDA)NH_2]-Exendin-4 for the diagnosis of recurrence or dissemination of medullary thyroid cancer : a preliminary report

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    Introduction. Epidemiological studies on medullary thyroid cancer (MTC) have shown that neither a change in stage at diagnosis nor improvement in survival has occurred during the past 30 years. In patients with detectable serum calcitonin and no clinically apparent disease, a careful search for local recurrence, and nodal or distant metastases, should be performed. Conventional imaging modalities will not show any disease until basal serum calcitonin is at least 150 pg/mL. The objective of the study was to present the first experience with labelled glucagon-like peptide-1 (GLP-1) analogue [Lys40(Ahx-HYNIC-99mTc/EDDA)NH2]-exendin-4 in the visualisation of MTC in humans. Material and Method. Four patients aged 22–74 years (two with sporadic and two with MEN2 syndrome-related disseminated MTC) were enrolled in the study. In all patients, GLP-1 receptor imaging was performed. Results. High-quality images were obtained in all patients. All previously known MTC lesions have been confirmed in GLP-1 scintigraphy. Moreover, one additional liver lesion was detected in sporadic MTC male patient. Conclusions. GLP-1 receptor imaging with [Lys40(Ahx-HYNIC-99mTc/EDDA)NH2]-exendin-4 is able to detect MTC lesions. GLP-1 scintigraphy can serve as a confirmatory test in MTC patients, in whom other imaging procedures are inconsistent

    Male, National, and Religious Collective Narcissism Predict Sexism

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    Results of three cross-sectional studies indicate that sexism in Poland is associated with collective narcissism—a belief that one’s own group’s (the in-group’s) exaggerated exceptionality is not sufficiently recognized by others—with reference to three social identities: male, religious, and national. In Study 1 (n = 329), male collective narcissism was associated with sexism. This relationship was sequentially mediated by precarious manhood and traditional gender beliefs. In Study 2 (n = 877), Catholic collective narcissism predicted tolerance of violence against women (among men and women) over and above religious fundamentalism and in contrast to intrinsic religiosity. In Study 3 (n = 1070), national collective narcissism was associated with hostile sexism among men and women and with benevolent sexism more strongly among women than among men. In contrast, national in-group satisfaction—a belief that the nation is of a high value—predicted rejection of benevolent and hostile sexism among women but was positively associated with hostile and benevolent sexism among men. Among men and women collective narcissism was associated with tolerance of domestic violence against women, whereas national in-group satisfaction was associated with rejection of violence against women

    Cross-Cultural Sexism and the Effectiveness of Gender (Non)Traditional Advertising: A Comparison of Purchase Intentions in Poland, South Africa, and the United Kingdom.

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    Findings regarding the effectiveness of (non)traditionally gendered advertisements are mixed and largely emanate from the United States. We tested the stereotype content model and ambivalent sexism theory cross-nationally in an advertising context and predicted that paternalistic (vs. envious) female stereotypes will trigger higher purchase intent (PI) irrespective of country (Hypothesis 1), viewers’ benevolent sexism will positively predict PI for paternalistic housewife advertisements (Hypothesis 2a), viewers’ hostile sexism will negatively predict PI for envious businesswoman advertisements (Hypothesis 2b), and these relationships with sexism will be confined to less gender egalitarian countries (i.e., Poland and South Africa) (Hypothesis 3). Statistical analyses of data from 468 Polish, South African, and British university students supported Hypothesis 1 and partially supported Hypotheses 2 and 3. The predicted patterns held for South Africa, but in Poland, viewers’ benevolence positively predicted PI for both advertisement types, with the exception of highly hostile women. British viewers’ hostility positively predicted PI for the housewife advertisement. Our findings support the cross-cultural applicability of the stereotype content model to advertising and suggest that the predictive role of sexism changes depending on its type, advertisement type, country, and gender. We recommend that advertisers should adopt a nuanced approach in predicting the effectiveness of gendered advertisements

    The situation on the credit market versus the rate of economic growth in chosen countries of East-Central Europe

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    The article concerns the comparative analysis concerning credit market situation on the background of economic growth changes in Poland, the Czech Republic, Lithuania and Hungary. The main objective of this article is to identify the similarities and differences in the economic situation of the whole economies and credits market conditions in individual countries. This relationship has been verified for each country. To determine the strength of the relationship between the dynamics of changes in the value of credits and GDP, Pearson correlation analysis was used. The basis of the analysis presented in the article was data from central banks, Central Statistical Office and Eurostat. Time horizon under investigation covered the period of 2004-2013. The results of analysis indicate that both the economic condition of entire economies, as well as the situation in the credit market remained diverse in all analyzed countries. Among the most significant similarities there was found that changes in the rate of economic growth in the analyzed countries remained at a moderate depending on the dynamics of changes in the credit market. Although the analyzed countries experienced a financial crisis, not all of them recorded a negative growth rate of GDP and credits

    Chaotic time series prediction with feed-forward and recurrent neural nets

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    The results of experimental comparison between several neural architectures for short-term chaotic time series prediction problem are presented. Selected feed-forward architectures (Multi-layer Perceptrons) are compared with the most popular recurrent ones (Elman, extended Elman, and Jordan) on the basis prediction accuracy, training time requirements and stability. The application domain is logistic map series - the well known chaotic time series predition benchmark problem. Simulation results suggest that in terms of prediction accuracy feed-forward networks with two hidden layers are superior to other tested architectures. On the other hand feed-forward architectures are, in general, more demanding in terms of training time requirements. Results also indicate that with a careful choice of learning parameters all tested architectures tend to generate stable (repeatable) results

    Laplacian mesh smoothing for tetrahedra based volume visualization

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    In this paper an improved method for three-dimensional (3-D) surface reconstruction from computed tomography slices is presented. Marching cubes (MC) is a popular method for extracting iso-surfaces from discrete (3-D) data. We implemented a simplification of marching cubes, commonly known as marching tetrahedrons (MT)

    Radioisotopes for medical and industrial use during the 50-year history of the Institute of Nuclear Research

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    The paper summarises the 50-years long history of the development of research programmes related to the practical applications of radionuclides in various fields of the Polish economy. The changing trends of interest of the potential users are reflected in the research and development activities of the Radioisotope Centre POLATOM. In the 1960's and 1970's the main areas of activity were focused on the sealed sources and radiolabelled compounds for the investigation of industrial processes. The introduction to the routine practice of the RIA and the IRMA kits for hormonal in vitro diagnostics in the 70-ties and 80-ties resulted in the general availability of this diagnostic technique in Poland. The number of radioisotopes having the required radiation type, energy and half-life is steadily increasing due to the progress in irradiation facilities and in chemical separation processes. The need for modern radiopharmaceuticals, more specific and providing higher diagnostic and therapeutic potential as an alternative to other medical modalities is reflected in the research programmes carried out and implemented currently at the Radioisotope Centre POLATOM
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