Preclinical studies of166Ho-chitosan for treatment of hepatocellular carcinoma

Introduction: Recently, due to the special characteristics of166Ho and chitosan,166Ho-chitosan complex was developed for treatment of tumors such as hepatocellular carcinoma. This complex has been lately prepared with high radiochemical purity in our lab. The preclinical studies of the complex however should be performed to evaluate the tracer concentration in target and normal tissues before human use. Methods: In this study,166Ho-chitosan was prepared and its preclinical studies for treatment of hepatocellular carcinoma was carried out by injection of the radiopharmaceutical into the rabbit's liver via two different methods, surgery and venography. Leakage of the injected activity from the injection site in the rabbit organs was investigated using SPECT and SPECT-CT imaging up to 24 hours. Results: Both SPECT and SPECT-CT imaging of the rabbits showed that there was no significant leakage of the injected activity. Almost all the activity would remain in the injection site at least 24 h post injection. Conclusion: Considering all of the excellent features of the complex, this radiopharmaceutical is suggestive for treatment of hepatocellular carcinoma by radioembolization method

Traumatic Pulmonary Pneumatoceles (Pseudocyst)

Introduction: Traumatic pulmonary parenchymal cavitary lesions (TPPCs) are pulmonary pseudocysts raiding secondary to lung contusion. Method: To provide an overview of the etiology, presentation, diagnosis and treatment of TPPCs, and to discuss this in the context of a cohort of 12 retrospectively reviewed patients with TPPCs presenting to Sahlgrenska University Hospital, Gothenburg, Sweden, from January 2014 to December 2016. Between January 2014 and December 2016, a total of twelve trauma patients presented to Sahlgrenska University Hospital with TPPC following blunt trauma. Results: TPPCs are of limited clinical consequence. Inexperienced clinicians may treat these inappropriately. A Computed Tomography (CT) scan is the investigation of choice. Treatment is symptomatic. Intervention is indicated only in case of complications

Razvoj radiomarkiranog β-humanog koriogonadotropina

-human chorionic gonadotropin (-hCG) was successively labeled with [67Ga] gallium chloride after conjugation with freshly prepared diethylenetriaminepentaacetic acid dianhydride (ccDTPA). After solid phase purification of the radiolabeled hormone, high performance liquid chromatography showed radiochemical purity higher than 95 % under optimized conditions (specific activity = 2223 TBq mM1, labeling efficiency 80 %). Preliminary in vivo studies (ID g1, %) in male wild-type rats showed marked gonadal uptake of the tracer after 240 minutes in agreement with the biodistribution studies and reported -hCG receptors. Target to blood ratios were 5.1 and 15.2 after 3 and 24 hours, respectively, while target to muscle ratios were 35 and 40 after 3 and 24 hours, respectively.Beta-humani korionski gonadotropin (beta-hCG) uspješno je markiran s [67Ga] galijevim kloridom nakon konjugacije sa svježe priređenim dianhidridom dietilentriaminpentaoctene kiseline (ccDTPA). Nakon čišćenja radiomarkiranog hormona na čvrstoj fazi, radiokemijska čistoća bila je prema HPLC veća od 95 % (specifična aktivnost = 22-23 TBq mM-1, učinkovitost markiranja 80 %). Preliminarni in vivo pokusi (ID g-1, %) na mužjacima divljeg tipa štakora pokazali su da obilježeni hormon značajno ulazi u gonade nakon 240 minuta, što je u suglasnosti s ispitivanjima biodistribucije i podacima o receptorima za beta-hCG. Omjer koncentracija u gonadama i krvi bio je 5,1, odnosno 15,2 nakon 3, odnosno 24 sata, dok je omjer koncentracija u gonadama i mišićima bio 35, odnosno 40 nakon 3, odnosno 24 sata

Monte Carlo simulation of response function of organic scintillators to gamma rays and neutrons using FLUKA, MCNPX and SCINFUL code

In organic scintillators, the energy distribution of gamma rays and neutrons is indirectly measured by the pulse height distribution of light output produced through gamma ray and neutron reactions in the detectors. Accurate estimate of the interaction of gamma and neutrons in the detector and produce charged secondary particles and subsequent scintillation light produced in the calculation of the response function is the most important. Although,, the complexity of the light generation on these scintillators makes modeling their response function difficult with standard Monte Carlo method. The paper reports generate the response function of an NE102 plastic scintillator when exposed to gamma rays and response function of a BC501A liquid scintillator to mono-energetic and Am-Be neutrons using the EVENTBIN card of the FLUKA code and the PTRAC card of the MCNPX code. The comparison between simulated and experimental response functions show that both FLUKA and MCNPX codes generated distributions are in good agreement with corresponding experimental results

Absorbed Dose Estimation of 177Lu-DOTATOC in Adenocarcinoma Breast Cancer Bearing Mice

In this study, the absorbed dose of human organs after injection of 177Lu-DOTATOC was studied based on the biodistribution of the complex in adenocarcinoma breast cancer bearing mice. For this purpose, the biodistribution of the radiolabelled complex was studied and compartmental modeling was applied to calculate the absorbed dose with high precision. As expected, 177Lu-DOTATOC illustrated a notable specific uptake in tumor and pancreas, organs with high level of somatostatin receptor on their surface and the effectiveness of the radio-conjugate for targeting of the breast adenocarcinoma tumors was indicated. The elicited results of modeling were the exponential equations, and those are utilized for obtaining the cumulated activity data by taking their integral. The results also exemplified that non-target absorbed-doses such as the liver, spleen and pancreas were approximately 0.008, 0.004, and 0.039, respectively. While these values were so much lower than target (tumor) absorbed-dose, it seems due to this low toxicity, this complex is a good agent for therapy

Preparation, quality control and biodistribution studies of [61Cu]-oxinate for PET tumor imaging

Targeting apoptosis is an interesting issue in molecular imaging and various modalities have been presented. However, recent experiences in nuclear pharmacy demonstrated the application of small tracer molecules is more desired. This work was conducted for production of a radiolabeled copper complex, i.e. 61Cu-oxinate as a potential PET tracer for apoptosis imaging in oncology. Cu-61 was prepared by natural zinc target irradiation with 22 MeV protons (150 miA) via the natZn(p, xn)61Cu nuclear reaction with a yield of 3.33 mCi/miAh. In order to obtain the best labeling method, optimization reactions were performed for pH, temperature and concentration followed by solid phase extraction. Biodistribution of the tracer was studied in wild-type and fibrosarcoma bearing mice. Under the optimized conditions, radio-thin-layer chromatography (RTLC) and HPLC showed radiochemical purities of 99.99% and 97% respectively (with a minimum specific activity of 16 Ci/mM). Biodistribution of the tracer in fibrosarcoma bearing mice demonstrated a significant tumor uptake after 3 h. Tumor:blood and tumor:muscle ratios were 2.0 and 6.0 after 3 h, respectively

Preparation and quality control of lutetium-177 bleomycin as a possible therapeutic agent

Due to interesting therapeutic properties of 177Lu and antineoblastic antibiotic, bleomycin (BLM), 177Lu-bleomycin (177Lu-BLM) was developed as a possible therapeutic compound. Lu-177 of 2.6-3 GBq/mg specific activity was obtained by irradiation of a natural Lu2O3 sample with a thermal neutron flux of 4 × 1013 nźcm-2źs-1. The product was converted into chloride form which was further used for labeling of BLM. In optimized conditions a radiochemical purity of 98% was obtained for 177Lu-BLM shown by instant thin-layer chromatography (ITLC) (specific activity, 740 GBq/mmole). Biodistribution studies of Lu-177 chloride and 177Lu-BLM were performed in wild-type rats. The accumulation of the radiolabeled compound in lungs, liver and spleen demonstrates a pattern similar to the other radiolabeled bleomycins. Lu-BLM is a possible therapeutic agent in human malignancies and the efficacy of the compound should be tested in various tumor-bearing models

Development of 153Sm-DTPA-rituximab for radioimmunotherapy

Combining beta-particle effect with therapeutic properties of anti-CD20 monoclonal antibody in lymphomas, Mabthera™ (rituximab) was targeted in this study. The antibody was labeled with 153Sm-samarium chloride (185 MBq) after conjugation with freshly prepared ccDTPA. Conjugated-rituximab was obtained by the addition of 1 ml of a rituximab pharmaceutical solution (5 mg/ml, in phosphate buffer, pH = 7.8) to a glass tube precoated with freshly prepared ccDTPA (0.01–0.1 mg) at 25 degrees centigrade. Sm-153 chloride was obtained by a thermal neutron flux (5 × 1013 nźcm–2źs–1) of an enriched 152Sm2O3 sample, dissolved in acidic media. Radiolabeling was performed in one hour by the addition of DTPA-rituximab conjugate at room temperature. Radiochemical purity of 96% (ITLC) and 98% (HPLC) were obtained for the final radioimmunoconjugate (specific activity = 120 TBq/mmol). The final isotonic 153Sm-rituximab complex was checked by gel electrophoresis for protein integrity retention. Biodistribution studies in normal rats were performed to determine radioimmunoconjugate distribution up to 24 h. SPECT images were also obtained using 103 keV photons up to 48 h

An Intracardiac Mass in a Pregnant Woman Presenting with Ventricular Tachycardia

A pregnant patient presented with symptomatic ventricular tachycardia. Echocardiography revealed a large intramyocardial mass. Surgical resection was attempted in conjunction with cryoablation of the surrounding myocardial tissue. Histologic examination of the resected mass revealed cardiac neurofibroma. To the best of our knowledge, this is the first report of cardiac neurofibroma in a pregnant patient in the absence of any neurocutaneous syndromes such as neurofibromatosis. © 2016 The Society of Thoracic Surgeons