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Preclinical studies of a new octreotide derivative with a chelate (DPAH-octreotide) that binds 99mTc for radiological diagnosis of neuroendocrine tumors are currently in progress. A method for preparing DPAH-octreotide is based on forming an amide bond between the amine of D-phenylalanine and the bifunctional chelate succinimid-1-yl 6-[bis(pyridin-2-ylmethyl)amino]hexanoate. An HPLC method for determining the identity, impurities, and quantitative content is proposed for DPAH-octreotide quality assurance. The validation protocol established that the HPLC analytical method for determining DPAH-octreotide had quality parameters for specificity, detection limit, linearity, accuracy, precision, and intralaboratory precision that met requirements for analytical methods and could be used for quality control of the finished product during manufacturing of reagents for preparation of related radiopharmaceuticals. [ABSTRACT FROM AUTHOR]

Experimental batches of iodine-123-labeled beta-methyl iodophenylpentadecanoic acid (123I-BMIPP) with an activity of 180 MBq/mL have been produced based on 123I extracted from enriched 122Te targets irradiated by accelerated deuterons at the R-7M cyclotron. It is shown that the radiochemical purity of 123I-BMIPP in EtOH solutions exceeds 96% at an acceptable content of the main chemical impurities (Cu, Te). The conditions of 123I-BMIPP dilution in human serum albumin (10%) solution for injection in experimental animals are determined. The biological behavior of the preparation in rats has been studied. It is established that 123I-BMIPP is characterized by pronounced accumulation in the heart. A qualitative scintigram of the rabbit heart was obtained and showed the possibility of external detection. It is established that it is possible to judge the viability of myocardium by measuring the amount of 123I-BMIPP accumulated in the heart. [ABSTRACT FROM AUTHOR]

Anatomic visualization and molecular typing of metastatic regional lymph nodes in breast cancer patients are a serious clinical challenge in modern oncology. According to the results of previous studies, [99mTc]Tc-(HE)3-G3 has proven to be a promising diagnostic agent in differentiating the HER2/neu receptor status in primary breast tumors ( p < 0.05, Mann-Whitney test). In this regard, the purpose of this study is to explore the possibilities of using [99mTc]Tc-(HE)3-G3 to determine the HER2/neu receptor status in the metastatic axillary lymph nodes (mALNs) of breast cancer patients. The study was conducted using clinical material from 20 breast cancer patients (T2-4N1-3M0-1) before systemic therapy (10 patients with positive and 10 patients with negative HER2/neu expression in mALNs) who underwent SPECT/CT scan 4 h after the administration of [99mTc]Tc-(HE)3-G3. Morphological and immunohistochemical studies of mALNs with assessment of the HER2/neu status were performed on all patients. We found that mALN-to-background and mALN-to-latissimus dorsi muscle ratios for [99mTc]Tc-(HE)3-G3 uptake 4 h after its administration may be used for typing of the HER2/neu status in mALNs of breast cancer patients ( p < 0.05, Mann-Whitney test). In that case, sensitivity and specificity for the mALN-to-background ratio were identical at 80%, with the threshold value being > 12.25., (Copyright ® 2024 National Research University Higher School of Economics.)

This review examines the evolution of the radionuclide diagnosis of HER2-positive breast cancer using various compounds as a targeting module in clinical practice: from full-length antibodies to a new group of small synthetic proteins called alternative scaffold proteins. This topic is of especial relevance today in view of the problems attendant to the detection of breast cancer with HER2/neu overexpression, which, in most cases, introduce errors in the treatment of patients. The results of clinical studies of radiopharmaceuticals based on affibody molecules, ADAPTs, and DARPins for SPECT and PET have demonstrated good tolerability of the compounds, their rapid excretion from the body, and the possibility to differentiate tumor sites depending on the HER2/neu status. This indicates that targeted radionuclide diagnosis holds promise and the need to continue research in this direction., (Copyright ® 2022 National Research University Higher School of Economics.)

The aim of the present work was to study cerebral hemodynamics and cognitive function in patients suffering from coronary artery disease (CAD) in the short- and long-term periods after coronary bypass grafting (CBG). The study accrued 65 patients who underwent myocardial revascularization using cardiopulmonary bypass (43 persons) and without heart interruption (22 persons). In 21 cases, CBG using cardiopulmonary bypass with a purpose of preventing cerebral events was supplemented by administration of instenon manufactured by the Nycomed Company, Perfusion tomoscintigraphy of the brain and neuropsychological testing were provided to all the patients prior to CBG, 14 days and 6 months following surgery. CBG coupled with preventive administration of instenon or beating heart operation allow to appreciably minimize the risk of disorders of cerebral hemodynamics and cognitive function in the long-term postoperative period.

Background: Twenty two patients with congestive cardiac failure treated surgically by dynamic cardiomyoplasty (CMP) with m. latissimus dorsi were examined. Myocardial perfusion was assessed with (199)TlCl scintigraphy combined with dipyridamole stress-test. In order to obtain direct evidence of myocardial perfusion from muscular flap we also injected a bolus of (99m)Tc into a. thoracodorsalis, with simultaneous blood sampling from coronary sinus. Haemodynamic parameters were assessed using radionuclide angiography., Methods: In a year of follow-up all the patients were assigned to one of two groups: eleven patients demonstrated improvement in clinical status (first group) and in another group comprising eleven persons no positive effect or deterioration were obvious (second group). The patients of the first group before operation revealed two times less persistent defect size than patients of the second group. Analysis of integral index of persistent defect revealed more expressive differences between groups. Before the surgical treatment the patients with improvement in clinical status after cardiomyoplasty demonstrated greater size of reversible defect in comparison with patients of the second group. In the second group coronary fraction of thallium accumulation was 1.4 times higher in comparison to the first group, as the result of myocardial hypertrophy in patients with bad prognosis. There were no significant differences between the two groups in Il/m level before cardiomyoplasty. Before the surgical treatment the patients with improvement in clinical status after cardiomyoplasty demonstrated greater ejection fraction in comparison with patients of the second group., Results: Cardiomyoplasty led to a decrease in the mean size of reversible defects due to indirect revascularisation. This hypothesis was testified to by the fact that in patients after cardiomyoplasty nuclide appeared in coronary sinus at 10-12th seconds after injection into artery thoracodorsalis through anastomoses between the latissimus dorsi muscle and the myocardium. The time of appearance of the second wave of rise gamma-counting in blood samples from coronary sinus reflects the repeated entry of radiopharmaceutical in myocardium after recirculation.

The efficacy of a new radionuclide, thallium-199 for myocardial scintigraphy was compared with conventional thallium-201 imaging. Owing to the short half-life of thallium-199 (7.4 hours), when the injected dose of thallium-199 was increased to 200 MBq, the total dose reaching the critical organs was 3.6-15.5 times lower than with conventional nuclide, thallium-201. Studies were performed in a total of 177 patients. The patients were divided into two groups(a) 17 patients with acute myocardial infarction and (b) 160 patients undergoing coronary angiography: 55 patients with no significant coronary artery disease and 105 patients with coronary disease. The sensitivity of the test was 92% with a specificity of 82% and overall predictive accuracy of 84%. Myocardial images obtained with low and high energy collimators have similar predictive accuracy. Perfusion defects were detected more frequently with increasing severity of angina. Myocardial infarction was characterized by persistent defects and myocardial ischaemia by redistribution of thallium. Thallium-199 myocardial scintigraphy performed at rest can be used for the diagnosis of acute myocardial infarction and for the determination of infarct site and extent. Thallium-199 is a new myocardial imaging agent, with a predictive accuracy for the diagnosis of coronary artery disease similar to thallium-201, but a significantly reduced total body dose permits repeat studies with a reduced radiation dose for the patient.

The pulmonary haemodynamics and thyroid hormone level were investigated in 21 patients with EKS-222 (VVI) pacemaker, implanted after successful transvenous electrical endocardial His-bundle fulguration (TEF). Triiodthyronine (T3) and thyroxine (T4) were determined by radioimmunoassay, pulmonary circulation parameters were estimated by means of radiocardiography and radionuclide ventriculography using an Omega 500 gamma-camera and a "Scintron MX" computer system. Patients with atrial fibrillation (AF) during VVI pacing had higher level of T3 and T4 and better pulmonary circulation parameters than those with persistent sinus node activity during paced rhythm.