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1.
Int J Radiat Biol ; 94(11): 996-1005, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30295106

RESUMO

PURPOSE OF THE STUDY: One of the main difficulties in radiation dose assessment is cells inability to reach mitosis after exposure to acute radiation. Premature chromosome condensation (PCC) has become an important method used in biological dosimetry in case of exposure to high doses. Various ways to induce PCC including mitotic cells fusion, chemical stimulation with calyculin A or okadaic acid give wide spectrum of application. The main goal of this study was to evaluate the utility of drug-induced PCC scoring procedure by testing 2 experimental modes where 150 and 75 G2/M-PCC phase cells were analyzed after exposure to high dose proton and X-ray radiation. Another aim is to determine the differences in cellular response induced by proton and photon radiation using a HPBL in vitro model as a further extension of our previous studies involving doses up to 4.0 Gy. MATERIALS AND METHODS: Total body exposure was simulated by irradiating whole blood collected from a healthy donor. Whole blood samples were exposed to two radiation types: 60 MeV protons and 250 kVp X-rays in the dose range of 5.0-20.0 Gy, the dose rate for protons was 0.075 and 0.15 Gy/s for X-rays. Post 48 h of human peripheral blood lymphocytes (HPBL) culture, calyculin A was added. After Giemsa staining, chromosome spreads were photographed and manually analyzed by scorers in the G2/M-PCC phase. In order to check the consistency of obtained results all scorers followed identical scoring criteria. Additionally, PCC index kinetics was evaluated for first 500 cells scored. CONCLUSIONS: Here we provide a different method of results analysis. Presented dose-response curves were obtained by calculating the value of counted excess chromosome fragments. The results indicated that obtained dose estimates as adequate in the high dose range till 18.0 Gy for both studied radiation types, giving an opportunity to further improve PCC assay procedure and shorten the analysis time i.e. in case of partial-body exposure. Moreover, the study presents preliminary results of HPBL cellular response after proton irradiation at high doses range showing differences of PCC index kinetics for different cell classes and cell distribution.


Assuntos
Cromossomos Humanos/efeitos da radiação , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Prótons/efeitos adversos , Adulto , Ciclo Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Feminino , Humanos , Linfócitos/citologia , Raios X/efeitos adversos
2.
Q J Nucl Med Mol Imaging ; 59(2): 152-60, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25719487

RESUMO

Glucagon-like peptide 1 (GLP-1) receptors expression has been found on many types of cancer cells. In case of benign insulinoma the density of those receptors is even higher than the density of somatostatin receptors. This article presents the results of clinical trials proving the utility of GLP-1 receptors imaging. Scintigraphy or positron emission tomography with the use of GLP-1 analogues labelled with appropriate radioisotopes (111In, 99mTc, 68Ga, 18F or 64Cu) seem to be superior compared with other available techniques in diagnosis of hardly detectable benign insulinoma. While surgery is the only effective therapy for insulinoma patients, therefore proper preoperative localization of the tumor allows sparing operation. Glucagon-like peptide 1 receptors might become also a target for imaging of other tumors such as gastrinoma, pheochromocytoma and medullary thyroid cancer (MTC), which also were shown to overexpress this type of receptors. However, studies with larger groups of patients are required to prove the clinical usefulness of this indication. Moreover GLP-1 receptor imaging seems to be a potential tool to evaluate pancreatic beta cell mass (BCM). It may be useful in the early diagnosis of beta cell loss in preclinical phases of diabetes. The panceratic beta cells imaging may influence the prophylaxis of diabetes and management of diabetic patients. Presented results of clinical trials prove that glucagon-like peptide 1 receptor imaging might become helpful diagnostic strategy particularly in case of patients with benign insulinoma tumors, but also patients with gastrinoma, pheochromocytoma, medullary thyroid cancer and diabetes.


Assuntos
Biomarcadores Tumorais/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/metabolismo , Peptídeos/metabolismo , Cintilografia/métodos , Peçonhas/metabolismo , Exenatida , Previsões , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Humanos , Marcação por Isótopo/métodos , Imagem Molecular/métodos , Imagem Molecular/tendências , Cintilografia/tendências , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacocinética
3.
Int J Endocrinol ; 2013: 384508, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23606839

RESUMO

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 [Lys(40)(Ahx-HYNIC-(99m)Tc/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 [Lys(40)(Ahx-HYNIC-(99m)Tc/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.

4.
IEEE Trans Vis Comput Graph ; 18(12): 2033-40, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26357109

RESUMO

In nuclear science, density functional theory (DFT) is a powerful tool to model the complex interactions within the atomic nucleus, and is the primary theoretical approach used by physicists seeking a better understanding of fission. However DFT simulations result in complex multivariate datasets in which it is difficult to locate the crucial `scission' point at which one nucleus fragments into two, and to identify the precursors to scission. The Joint Contour Net (JCN) has recently been proposed as a new data structure for the topological analysis of multivariate scalar fields, analogous to the contour tree for univariate fields. This paper reports the analysis of DFT simulations using the JCN, the first application of the JCN technique to real data. It makes three contributions to visualization: (i) a set of practical methods for visualizing the JCN, (ii) new insight into the detection of nuclear scission, and (iii) an analysis of aesthetic criteria to drive further work on representing the JCN.

5.
Eur J Nucl Med Mol Imaging ; 34(10): 1545-55, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17653543

RESUMO

PURPOSE: Radio-guided surgery (RGS) is an intra-operative localising technique which enables identification of tissue "marked" by a specific radiotracer injected before surgery. It is mainly used for sentinel node mapping and for detection of parathyroid adenomas and other tumours, including neuroendocrine tumours of the gastrointestinal tract (GEP-NET). The aim of this study was to determine whether intra-operative radio-detection with the use of [(99m)Tc-EDDA/HYNIC]octreotate, a new somatostatin analogue, is able to reveal an unknown primary and secondary sites, thereby improving surgical treatment and the final outcome of GEP-NET. METHODS: The study group included nine patients with suspected GEP-NET (four carcinoids, five pancreatic NET) localised with somatostatin receptor scintigraphy (with [(99m)Tc-EDDA/HYNIC]octreotate), who had negative results on other pre-operative imaging tests. At surgery, suspected tumours were measured in situ and ex vivo and precise exploration of the abdominal cavity was performed with the intra-operative scintillation detector (Navigator). RESULTS: Intra-operative gamma counting localised three carcinoids. In one patient SRS was false positive (owing to inflammatory infiltration). Compared with SRS, RGS revealed additional lymph node metastases in one case. RGS resulted in successful localisation of all pancreatic NET (the smallest lesion was 8 mm in diameter). CONCLUSION: [(99m)Tc-EDDA/HYNIC]octreotate SRS followed by RGS is a promising technique to improve the rate of detection and efficacy of treatment of GEP-NET, especially in the presence of occult endocrine tumours. The imaging properties of [(99m)Tc-EDDA/HYNIC]octreotate and the 1-day imaging protocol offer opportunities for more widespread application of this tracer followed by RGS in oncology.


Assuntos
Carcinoma Neuroendócrino/diagnóstico por imagem , Carcinoma Neuroendócrino/cirurgia , Neoplasias Gastrointestinais/diagnóstico por imagem , Neoplasias Gastrointestinais/cirurgia , Octreotida/análogos & derivados , Compostos de Organotecnécio , Cirurgia Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Cintilografia , Compostos Radiofarmacêuticos , Resultado do Tratamento
6.
Exp Clin Endocrinol Diabetes ; 115(1): 47-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17286235

RESUMO

UNLABELLED: Pulmonary carcinoids cause serious difficulties in imaging diagnostics in all stages of the disease. SRS holds great promise for detecting occult primary tu and metastatic lesions. (99m)Tc-EDDA/HYNIC-octreotate, a new scintigraphic agent, should significantly improve sensitivity of the diagnostics of carcinoids due to better affinity to SSR2 than (111)In-Octreoscan and the higher count rate obtained from (99m)Tc over (111)In. We present a case of a 40-year-old women operated on because of lung carcinoid tumour in 2002. The symptoms did not resolve after the operation and 5-OHIAA was still elevated. The thorax spiral CT revealed the focal lesion beneath carina. (111)In-Octreoscan and (99m)Tc-EDDA/HYNIC-octreotate SRS revealed two focal lesions in the mediastinum. (99m)Tc-EDDA/HYNIC-octreotate detected two additional lesions in the lower part of the right lung. Target/non-target count ratios of the lesions were as follows: (99m)Tc-EDDA/HYNIC-octreotate scans - 2,9, (111)In-Octreoscan- 2,1. PET-FDG examination revealed no pathology. Owing to severe bone pains and carcinoid symptoms the patient was referred for the 90Y-DOTA-octreotate treatment. CONCLUSIONS: SRS with a new 99mTc marked somatostatin analogue - octreotate allows for a more sensitive detection of metastatic leasions in carcinoid tumours. The usefulness of 18F-FDG PET, widely used as a powerful imaging technique in clinical oncology, is limited in detection of carcinoid tumours due to the low proliferative activity.


Assuntos
Tumor Carcinoide/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias do Mediastino/diagnóstico por imagem , Compostos Radiofarmacêuticos/administração & dosagem , Adulto , Tumor Carcinoide/terapia , Ácido Edético/administração & dosagem , Ácido Edético/análogos & derivados , Feminino , Humanos , Hidrazinas , Neoplasias Pulmonares/terapia , Neoplasias do Mediastino/secundário , Neoplasias do Mediastino/terapia , Metástase Neoplásica , Ácidos Nicotínicos , Compostos de Organotecnécio/administração & dosagem , Radiografia , Somatostatina/administração & dosagem , Somatostatina/análogos & derivados
7.
Eur J Nucl Med Mol Imaging ; 33(10): 1123-33, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16721571

RESUMO

PURPOSE: At all stages of the disease, serious difficulties are encountered in the imaging diagnosis of carcinoids. Somatostatin receptor scintigraphy (SRS) holds great promise for detecting primary tumours and metastases. 99mTc-EDDA/HYNIC-octreotate should significantly improve the diagnosis of carcinoids in comparison with 111In-Octreoscan owing to the better affinity for SSR2 and the higher count rate. The aim of this study was to assess the diagnostic efficiency of 99mTc-EDDA/HYNIC-octreotate scintigraphy in the detection and staging of carcinoid tumours. METHODS: The study population comprised 75 patients (age 48.5+/-15.5 years): 46 with histological confirmation of carcinoid and 29 with suspected disease. 99mTc-EDDA/HYNIC-octreotate (740 MBq) SRS and CT were performed in all patients. Fifteen patients were examined with 111In-Octreoscan. RESULTS: High-quality 99mTc-EDDA/HYNIC-octreotate images were obtained in all cases, with maximum tumour tracer accumulation 4 h p.i. The mean target/non-target ratios for whole body (WB) and SPECT scans were, respectively, as follows: primary lesions: 4.5 and 10.2; metastases: liver, 3.1 and 12.3; abdominal focal lesions, 2.7 and 5.8; lung, 2.7 and 8.3; mediastinum, 3.4 and 7.6; bones, 6.8 and 19.0. 99mTc-EDDA/HYNIC-octreotate WB scans revealed more metastases than 111In-Octreoscan, with better individual separation. 99mTc-EDDA/HYNIC-octreotate SRS revealed new metastatic lesions in seven patients with confirmed carcinoid, and in four with dissemination the primary focus was found. Five patients qualified for radioguided surgery and 11 were referred to 90Y-DOTA-TATE therapy. The sensitivity of SRS in comparison with CT was higher for primary lesions and liver and abdominal lymph node metastases. In the subgroup of patients with suspected neuroendocrine tumours, two duodenal carcinoids, one thymic carcinoid and one ileal carcinoid were found. CONCLUSION: 99mTc-EDDA/HYNIC-octreotate, with high imaging quality, is an excellent alternative to 111In-Octreoscan for staging of carcinoids, and it seems to be the method of choice for detection of the primary focus in patients with metastases from an unknown primary tumour.


Assuntos
Tumor Carcinoide/diagnóstico por imagem , Octreotida/análogos & derivados , Compostos de Organotecnécio , Ácido Pentético/análogos & derivados , Adolescente , Adulto , Idoso , Tumor Carcinoide/patologia , Criança , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cintilografia , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
J Endocrinol Invest ; 26(2 Suppl): 7-10, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12762633

RESUMO

Iodine prophylaxis was introduced in Poland in 1935. It was interrupted twice, the first time between 1939 and 1947 (due to the Second World War and its aftermath), and then between 1980 and 1986, due to the economical crisis in Poland at that time. A voluntary model of iodine prophylaxis (20 +/- 10 mg/kg of household salt) introduced in Poland in 1986, was followed by a mandatory model, implemented at the beginning of 1997, with 30 +/- 10 mg/kg of household salt. In the early sixties, in our Department of Endocrinology 24-hour iodine uptake test was introduced as a routine procedure for evaluating the thyroid gland. The reference value of this test increased in 1986 after discontinuation of iodine prophylaxis, and decreased in 1998, two years after re-implementation of the mandatory model of iodine prophylaxis. In 167 patients (147 with endemic goiter and 20 with no thyroid disturbances) examined between 1998 and 2000 the mean value of 24-hour iodine uptake was 27.3 +/- 10.4%, as compared to the mean value of 45,7 +/- 6.6 % in 1986. In patients with thyrotoxicosis the mean value of iodine uptake was 41.9% +/- 16.2 in 1999 (no.=614), 42.4% +/- 16.9 in 2000 (no.=644) and 37,7% +/- 17.2 at the beginning of 2001 (no.=328). The mean value of iodine uptake in patients with thyrotoxicosis before implementation of iodine prophylaxis was over 60%. The 24-hour thyroid radioiodine uptake test proved to be a useful indicator of changes of iodine intake in a iodine-deficient population. The data presented in this study confirm the importance and efficacy of the iodine prophylaxis introduced in Poland.


Assuntos
Bócio/metabolismo , Radioisótopos do Iodo/farmacocinética , Iodo/deficiência , Iodo/uso terapêutico , Medicina Preventiva , Glândula Tireoide/metabolismo , Adulto , Estudos de Casos e Controles , Ritmo Circadiano , Deficiências Nutricionais/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Tireotoxicose/metabolismo
9.
Neurol Neurochir Pol ; 22(3): 221-7, 1988.
Artigo em Polonês | MEDLINE | ID: mdl-3221960

RESUMO

In a group of 139 patients with poorly differentiated brain gliomas controlled clinical trial was carried out for assessment of two methods of postoperative treatment. After possibly radical removal of the glioma the patients were treated by radiotherapy with 60Co teletherapy in doses of 60 Gy (30 fr) in depth during 6 weeks, and randomly chosen patients received also CCNU in one dose of 100 mg/m repeated at intervals of 6-8 weeks. The administration of CCNU failed to improve the therapeutic results. The median survival time in the whole group was 49 weeks. The survival rate after 1, 2 and 3 years was 45.4%, 22.8% and 14.9% respectively. The survival times of cases of glioblastoma multiforme were not significantly different from those of patients with other poorly differentiated gliomas independently of the treatment method. The complications were not troublesome.


Assuntos
Neoplasias Encefálicas/cirurgia , Radioisótopos de Cobalto/administração & dosagem , Glioma/cirurgia , Lomustina/administração & dosagem , Teleterapia por Radioisótopo , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Diferenciação Celular , Feminino , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Fatores de Tempo
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