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1.
Curr Med Imaging Rev ; 15(10): 1001-1005, 2019.
Article En | MEDLINE | ID: mdl-32008528

BACKGROUND: Supernumerary kidney is an accessory organ with its own encapsulated parenchyma, blood vessels and ureters, either separated from the normal kidney or connected to it via fibrous tissue and ectopic kidney is a migration abnormality of the kidney. Here, we have evaluated a rare case of the supernumerary and ectopic kidney with DMSA, MAG3 and also CT fusion of the images. METHODS: The absolute divided renal function was calculated for each kidney by DMSA. The MAG3 scintigraphy showed no obstruction in the ureteropelvic junction. Furthermore, the renogram curve and Tmax and time to ½ values were assessed. Two months after the conventional scintigraphies, the patient was referred to a CT scan and the fusion of DMSA SPECT and CT data was generated on a workstation. RESULTS: The ectopic supernumerary kidney was functioning very well except a small hypoactive area, visible on DMSA, which was possibly a minimal pelvicalyceal dilatation. However, consequent CT scan did not show any pathology. CONCLUSION: It is important to evaluate particularly complicated or rare cases with multimodality systems with 3D or fusion techniques for the accurate diagnosis.


Choristoma/physiopathology , Kidney , Pelvis , Adult , Choristoma/diagnostic imaging , Choristoma/metabolism , Female , Humans , Pelvis/diagnostic imaging , Positron-Emission Tomography , Radiopharmaceuticals/pharmacokinetics , Technetium Tc 99m Dimercaptosuccinic Acid/pharmacokinetics , Technetium Tc 99m Mertiatide/pharmacokinetics , Ultrasonography
2.
Appl Radiat Isot ; 138: 25-28, 2018 Aug.
Article En | MEDLINE | ID: mdl-28781122

The dose to kidneys of newborns and 1-year old children was calculated using the MIRD methodology. In order to perform renal studies radiopharmaceutical like 99mTc-DTPA, 99m Tc-MAG3 and 99mTc-DMSA are used. Here, besides the anatomic and structure information of kidneys another data are provided in benefit of patient, however during the radioisotope decay emitted radiations delivers, totally or partially, their energy. Therefore is important to estimate the internal radiation dose of the organs. The largest dose to kidneys comes from the self-dose and it is due to the charged particles emitted during 99mTc decay. From the three radiopharmaceutical here used the largest dose to kidneys is due to 99mTc-DMSA, and the smaller dose is due to 99mTc-MAG3.


Kidney/diagnostic imaging , Radioisotope Renography/methods , Radiopharmaceuticals , Technetium Tc 99m Dimercaptosuccinic Acid , Technetium Tc 99m Mertiatide , Technetium Tc 99m Pentetate , Female , Humans , Infant , Infant, Newborn , Kidney/radiation effects , Kidney Function Tests/methods , Male , Radiation Dosage , Radiometry , Radiopharmaceuticals/pharmacokinetics , Technetium Tc 99m Dimercaptosuccinic Acid/pharmacokinetics , Technetium Tc 99m Mertiatide/pharmacokinetics , Technetium Tc 99m Pentetate/pharmacokinetics
3.
Pak J Pharm Sci ; 30(4): 1289-1295, 2017 Jul.
Article En | MEDLINE | ID: mdl-29039327

A Technetium 99mTc labeled lyophilized single component kit of N-N-ethylene-I-dicysteine (EC) is developed to replace multiple step kit developed by others. The aim of study is to formulate a radionuclide that is easy to prepare, has rapid plasma clearance, produce high quality images and is an affective alternative to radioiodine labeled orthoiodohippurate, which has been remained the physiological 'gold standard' since long time. To achieve this goal, the systematically varied key parameters such as pH, the use of reducing agents, stabilizers and additives are optimized to obtain maximum radiochemical purity and optimum biodistribution in non human and human primates. Various pH levels of EC showed equally good results in animal experiments but only pH 10 was suitable for human use. Dynamic and renal Scintigraphic studies are carried out with 99mTc-EC at pH 8 in 12 volunteers and at pH 10 in 18 volunteers and compared with 99mTc-MAG3, Background ratios, renograms, relative renal function and semi quantitative parameters are available in all studies. The background ratios (mean ± SD) at 30th minute are 0229±0.024 and 0.236±0.018 for 99mTc-EC at pH 10 and 99mTc-MAG3 respectively. The mean ± standard error of mean (SEM) values of TMAX and time to half activity (T12) for 99mTc-EC (pH10) are 3.7±0.6 and 7.3±1.0 respectively while for 99mTc-MAG3, they are 4.0±0.8 and 7.9±1.4 with p values 0.001 and 0.049 respectively. The values of relative renal function (RRF) for 99mTc-EC and 99mTc-MAG3 are 50.8±3.11 and 51.2±3.4 respectively with p value of 0.822. The residual activity at 25th minute (A25 / A MAX) and renal uptake are 0. 209±12.67±2.80 for 99mTc-EC and 0.218±0.035 and 1053±2.98 for 99mTc-MAG3 (p=0.031 an 0.0003) respectively. The correlation coefficient (R2) for TMAX, T1/2, A25/AMAX and renal uptake are 0.96, 0.69, 0.93 and 0.85 respectively.


Cysteine/analogs & derivatives , Kidney Function Tests/methods , Technetium Tc 99m Mertiatide/pharmacokinetics , Technetium/pharmacokinetics , Adult , Aged , Animals , Cysteine/chemistry , Cysteine/pharmacokinetics , Drug Compounding/methods , Female , Humans , Hydrogen-Ion Concentration , Macaca mulatta , Male , Middle Aged , Radionuclide Imaging , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/pharmacokinetics , Technetium/chemistry , Technetium Tc 99m Mertiatide/chemistry , Tissue Distribution , Young Adult
4.
Urology ; 108: 149-154, 2017 Oct.
Article En | MEDLINE | ID: mdl-28595935

OBJECTIVE: To determine the clinical value of visually assessed renal tissue transit time (TTT) in 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) renography for patients undergoing pyeloplasty. MATERIALS AND METHODS: Medical records of 164 patients who underwent dismembered pyeloplasty were retrospectively reviewed. Baseline and postoperative renal ultrasonography and 99mTc-MAG3 renography were performed. Two urologists blinded to clinical data evaluated the renography and classified TTT as timely or delayed based on visualization of the tracer in the kidney pelvis between 2 and 10 minutes. Renal functional change after pyeloplasty was compared between patients in the timely and delayed groups. RESULTS: A total of 126 patients (median age, 9 months) were evaluated after excluding patients with bilateral ureteropelvic junction obstruction, a single functioning kidney, duplicated ureter, or <3 months of follow-up. There were no differences between 89 patients with timely TTT and 37 patients with delayed TTT in mean preoperative hydronephrosis grade (3.7 vs 3.8) and pelvic diameter (3.1 cm vs 3.4 cm). Although the pre- and postoperative mean values of differential renal function (DRF) were significantly higher in the timely group than in the delayed group (47.2% vs 38.3% and 47.9% vs 44.6%), DRF change was greater in the delayed group (6.3% vs 0.6%). In multivariate analysis, delayed TTT was the only significant predictor of >5% improvement in renal function after pyeloplasty. CONCLUSION: Delayed TTT in 99mTc-MAG3 renography was a significant predictor of renal functional improvement after pyeloplasty in ureteropelvic junction obstruction. Because substantial improvement of renal function is anticipated, we recommend immediate pyeloplasty in patients with delayed TTT and decreased DRF.


Glomerular Filtration Rate/physiology , Kidney/physiopathology , Plastic Surgery Procedures/methods , Radioisotope Renography/methods , Technetium Tc 99m Mertiatide/pharmacokinetics , Ureteral Obstruction/diagnostic imaging , Urologic Surgical Procedures/methods , Disease Progression , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Kidney/diagnostic imaging , Kidney/metabolism , Kidney Pelvis/diagnostic imaging , Male , Postoperative Period , Radiopharmaceuticals/pharmacokinetics , Retrospective Studies , Time Factors , Ureter/surgery , Ureteral Obstruction/physiopathology , Ureteral Obstruction/surgery
5.
Nucl Med Commun ; 38(2): 124-128, 2017 Feb.
Article En | MEDLINE | ID: mdl-27851658

OBJECTIVE: This study aims to evaluate interobserver agreement on visual analysis of technetium-99m mercaptoacetyltriglycine (Tc-MAG3) renal tissue transit used for the evaluation of antenatal hydronephrosis. MATERIALS AND METHODS: Thirty-eight Tc-MAG3 diuretic renograms were retrospectively collected between 1 and 31 December 2015. The 1-min reframed images were presented to four nuclear medicine consultants and to two nuclear medicine residents, one in the first year of the training program and the others in their fourth and final year. These observers were asked to classify the radiotracer cortical transit (normal/delayed) based solely on visual assessment of the images. For the interobserver agreement, modified Fleiss' kappa (κ) analysis for multiple raters was carried out. For both groups, percentages of agreement were also calculated. RESULTS: A total of 69 kidneys were evaluated. All four nuclear medicine consultants agreed on the classification of 88.4% of the kidneys. When the agreement of at least three of the four observers was considered, the percentage of agreement reached 98.6%. The two nuclear medicine residents agreed on the classification of 69.6% of the kidneys. The modified Fleiss' κ-value was 0.88 (95% confidence interval: 0.79-0.95) for the group of nuclear medicine consultants, indicating almost perfect agreement. For the residents, it was 0.39 (95% confidence interval: 0.16-0.59), suggesting fair agreement. CONCLUSION: Our results seem to indicate that there is an almost perfect agreement in the qualitative identification of delayed cortical transit among physicians with experience at observing renographic images.


Hydronephrosis/congenital , Hydronephrosis/diagnostic imaging , Radioisotope Renography/methods , Technetium Tc 99m Mertiatide , Adolescent , Child , Child, Preschool , Humans , Hydronephrosis/metabolism , Infant , Infant, Newborn , Kidney/abnormalities , Kidney/diagnostic imaging , Kidney/metabolism , Kidney Cortex/diagnostic imaging , Kidney Cortex/metabolism , Observer Variation , Radiopharmaceuticals/pharmacokinetics , Retrospective Studies , Technetium Tc 99m Mertiatide/pharmacokinetics
6.
Oncotarget ; 7(27): 41233-41241, 2016 Jul 05.
Article En | MEDLINE | ID: mdl-27259246

Peptide Receptor Radionuclide Therapy (PRRT) for the treatment of neuroendocrine tumors may lead to kidney deterioration. This study aimed to evaluate the suitability of 99mTc-mercaptoacetyltriglycine (99mTc--MAG3) clearance for the early detection of PRRT-induced changes on tubular extraction (TE). TE rate (TER) was measured prior to 128 PRRT cycles (7.6±0.4 GBq 177Lu-octreotate/octreotide each) in 32 patients. TER reduction during PRRT was corrected for age-related decrease and analyzed for the potential to predict loss of glomerular filtration (GF). The GF rate (GFR) as measure for renal function was derived from serum creatinine. The mean TER was 234 ± 53 ml/min/1.73 m² before PRRT (baseline) and 221 ± 45 ml/min/1.73 m² after a median follow-up of 370 days. The age-corrected decrease (mean: -3%, range: -27% to +19%) did not reach significance (p=0.09) but significantly correlated with the baseline TER (Spearman p=-0.62, p<0.001). Patients with low baseline TER showed an improved TER after PRRT, high decreases were only observed in individuals with high baseline TER. Pre-therapeutic TER data were inferior to plasma creatinine-derived GFR estimates in predicting late nephropathy. TER assessed by 99mTc-MAG3-clearance prior to and during PRRT is not suitable as early predictor of renal injury and an increased risk for late nephropathy.


Glomerular Filtration Rate/radiation effects , Kidney Diseases/diagnosis , Kidney Tubules/metabolism , Kidney Tubules/radiation effects , Octreotide/analogs & derivatives , Radiation Injuries/diagnosis , Technetium Tc 99m Mertiatide/pharmacokinetics , Adult , Aged , Female , Humans , Kidney Diseases/etiology , Male , Middle Aged , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/metabolism , Neuroendocrine Tumors/radiotherapy , Octreotide/adverse effects , Octreotide/therapeutic use , Prognosis , Retrospective Studies , Single Photon Emission Computed Tomography Computed Tomography , Young Adult
8.
Nephrology (Carlton) ; 19(4): 210-6, 2014 Apr.
Article En | MEDLINE | ID: mdl-24387277

AIM: The sulfonamide group is widely used for bacterial diseases including kidney and urinary tract infections. The present study investigates the effect of a sulfa drug on kidney function and renography studies by using a radionuclide. METHODS: Renography studies were performed on New Zealand white rabbits. Each rabbit was injected with 48.1 MBq technetium-99m mercaptoacetyltriglycine ((99m) Tc-MAG-3). Dynamic images were acquired using a gamma camera. Radioactivity time curves were generated from the regions of interest, time to peak activity (Tmax ) and time from peak to 50% activity (T1/2 ). Each rabbit served as its own control. The sulfa drug was given to these rabbits for 7 days (i.v injection 130 mg/kg daily in two divided doses; i.e. the single dose is 65 mg/kg), then dynamic images were acquired. RESULTS: Treatment with sulfa shifted the experimental curves to the right of the control curves. This result showed that there was a delayed renal uptake of (99m) Tc-MAG-3 and its clearance. Calculated averages of Tmax were 2.2 ± 0.3 and 5.9 ± 0.5 min; while for T1/2 were 3.1 ± 0.3 and 8.4 ± 0.6 min for control and sulfa-treated rabbits, respectively (n = 20; P < 0.05). CONCLUSION: Our results indicate that sulfa drug induced pharmacokinetic changes because of delaying both the Tmax and T1/2 . Sulfa drug has an effect on the reabsorption from the renal tubules and the excretion process of (99m) Tc-MAG-3 which is excreted almost exclusively by the renal tubules. Therefore, sulfa drug causes a deterioration in kidney function and an alteration on radionuclide renography.


Anti-Bacterial Agents/toxicity , Kidney/drug effects , Radioisotope Renography , Sulfonamides/toxicity , Animals , Anti-Bacterial Agents/administration & dosage , Half-Life , Injections, Intravenous , Kidney/diagnostic imaging , Kidney/physiopathology , Male , Metabolic Clearance Rate , Rabbits , Radiopharmaceuticals/pharmacokinetics , Renal Reabsorption , Sulfonamides/administration & dosage , Technetium Tc 99m Mertiatide/pharmacokinetics
9.
BMC Urol ; 14: 3, 2014 Jan 07.
Article En | MEDLINE | ID: mdl-24397735

BACKGROUND: To investigate functional aspects of silent ureteral stones with special focus on obstruction and its relationship to renal anatomy. The present study is the first investigation of renal excretory function in patients with silent ureteral stones. METHODS: Patients with primarily asymptomatic ureteral stones underwent a mercapto-acetyltriglycine (MAG-3) renal scintigraphy prior to treatment, in addition to anatomic evaluation of renal units and serum creatinine levels. The primary outcome measure was the presence or absence of obstruction. Secondary outcome measures were kidney anatomy, grade of hydronephrosis, location of stones, stone size, and serum creatinine levels. RESULTS: During a ten-year period, 14 patients (median age 52.6 years; range 37.3 to 80.7 years) were included in the study. The relative frequency of primarily asymptomatic ureteral stones among all patients treated for ureteral stones in the study period was 0.7%. Eleven renal units showed some degree of hydronephrosis while 3 kidneys were not dilated. On the MAG-3 scan, 7 patients had an obstruction of the ureter, 5 had no obstruction, and 2 had dysfunction of the kidney. A statistically significant correlation was established between the grade of obstruction and stone size (p = 0.02). CONCLUSIONS: At the time of presentation, only 64.3% of the patients revealed an obstruction in the stone-bearing renal unit. The degree of hydronephrosis and renal function were very diverse in this subgroup of patients with ureteral stones. The onset of ureterolithiasis and the chronological sequence of obstruction remain unclear in patients who have never experienced symptoms due to their stones.


Kidney Function Tests/methods , Technetium Tc 99m Mertiatide/pharmacokinetics , Ureter/physiopathology , Ureteral Calculi/physiopathology , Ureteral Obstruction/physiopathology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Radionuclide Imaging , Radiopharmaceuticals/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity , Ureter/diagnostic imaging , Ureteral Calculi/complications , Ureteral Calculi/diagnostic imaging , Ureteral Obstruction/diagnostic imaging , Ureteral Obstruction/etiology
10.
Intern Med ; 52(9): 987-91, 2013.
Article En | MEDLINE | ID: mdl-23648719

Acute kidney injury (AKI) is a well-recognized complication of minimal change nephrotic syndrome (MCNS). Previous reports support the concept that AKI associated with MCNS is reversible; however, information regarding the hemodynamic basis of AKI in MCNS is insufficient. We herein describe a case of AKI in a man with MCNS. In this case, monitoring the longitudinal changes in renal perfusion using serial Tc-99m-MAG3 renal scanning was beneficial for evaluating the pathophysiological background associated with the development of AKI. The potential impact of serial renal scanning in MCNS patients with AKI will also be discussed.


Acute Kidney Injury/diagnostic imaging , Nephrosis, Lipoid/diagnostic imaging , Radiopharmaceuticals , Technetium Tc 99m Mertiatide , Acute Kidney Injury/chemically induced , Aged , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Disease Susceptibility , Fracture Fixation, Internal , Humans , Humeral Fractures/complications , Humeral Fractures/surgery , Kidney Tubules/diagnostic imaging , Kidney Tubules/metabolism , Male , Nephrosclerosis/complications , Nephrosclerosis/diagnosis , Nephrosclerosis/pathology , Nephrosis, Lipoid/chemically induced , Nephrosis, Lipoid/physiopathology , Pain, Postoperative/drug therapy , Phenylpropionates/adverse effects , Phenylpropionates/therapeutic use , Prednisolone/therapeutic use , Radionuclide Imaging , Radiopharmaceuticals/pharmacokinetics , Remission Induction , Technetium Tc 99m Mertiatide/pharmacokinetics
11.
Clin Physiol Funct Imaging ; 33(5): 353-8, 2013 Sep.
Article En | MEDLINE | ID: mdl-23701132

Several single sample methods for determination of (99m)Tc-mercaptoacetyltriglycine (MAG3) clearance are being used clinically. Kabasakal et al. proposed a similar formula for (99m)Tc-ethylenedicysteine (EC). This study was performed to compare his method with Bubeck et al. formula for (99m)Tc-MAG3 already in use. Twenty-eight subjects divided in two groups were registered which included 22 patients with various renal diseases (group-I) and six normal volunteers (group II). All subjects were studied twice using both the radiopharmaceuticals. The images and renogram parameters, that is TMAX and T1/2 of both the agents, were similar in all the subjects. The clearance of the (99m)Tc-EC was however considerably higher than (99m)Tc-MAG3 in both the groups (mean ± SEM =279 ± 14 ml min(-1)/1.73 m(2) versus 177 ± 15 ml min(-1)/1.73 m(2) in group-I and 377 ± 11.90 ml min(-1)/1.73 m(2) versus 238 ± 8.23 ml min(-1)/1.73 m(2) in group II). This difference was more pronounced in cases with reduced renal functions. Among the Effective Renal Plasma Flow (ERPF) values determined from EC and MAG3 clearances in six normal volunteers, four cases only in MAG3 had ERPF below the lower limit. This study has demonstrated superiority of single sample method for (99 m)Tc-EC clearance over its analogous method for (99m)Tc-MAG3.


Cysteine/analogs & derivatives , Kidney Diseases/diagnostic imaging , Kidney/diagnostic imaging , Organotechnetium Compounds , Radioisotope Renography/methods , Radiopharmaceuticals , Technetium Tc 99m Mertiatide , Adolescent , Adult , Aged , Case-Control Studies , Cysteine/blood , Cysteine/pharmacokinetics , Female , Half-Life , Humans , Kidney/blood supply , Kidney/physiopathology , Kidney Diseases/blood , Kidney Diseases/physiopathology , Male , Metabolic Clearance Rate , Middle Aged , Organotechnetium Compounds/blood , Organotechnetium Compounds/pharmacokinetics , Predictive Value of Tests , Radiopharmaceuticals/blood , Radiopharmaceuticals/pharmacokinetics , Renal Plasma Flow, Effective , Severity of Illness Index , Technetium Tc 99m Mertiatide/blood , Technetium Tc 99m Mertiatide/pharmacokinetics , Young Adult
12.
Phys Med Biol ; 58(10): 3145-61, 2013 May 21.
Article En | MEDLINE | ID: mdl-23603770

In dynamic renal scintigraphy, the main interest is the radiopharmaceutical redistribution as a function of time. Quality control (QC) of renal procedures often relies on phantom experiments to compare image-based results with the measurement setup. A phantom with a realistic anatomy and time-varying activity distribution is therefore desirable. This work describes a pharmacokinetic (PK) compartment model for (99m)Tc-MAG3, used for defining a dynamic whole-body activity distribution within a digital phantom (XCAT) for accurate Monte Carlo (MC)-based images for QC. Each phantom structure is assigned a time-activity curve provided by the PK model, employing parameter values consistent with MAG3 pharmacokinetics. This approach ensures that the total amount of tracer in the phantom is preserved between time points, and it allows for modifications of the pharmacokinetics in a controlled fashion. By adjusting parameter values in the PK model, different clinically realistic scenarios can be mimicked, regarding, e.g., the relative renal uptake and renal transit time. Using the MC code SIMIND, a complete set of renography images including effects of photon attenuation, scattering, limited spatial resolution and noise, are simulated. The obtained image data can be used to evaluate quantitative techniques and computer software in clinical renography.


Gamma Cameras , Models, Biological , Monte Carlo Method , Phantoms, Imaging , Radioisotope Renography/instrumentation , Technetium Tc 99m Mertiatide/pharmacokinetics , Female , Humans , Image Processing, Computer-Assisted , Male , Quality Control
13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 45(2): 250-4, 2013 Apr 18.
Article Zh | MEDLINE | ID: mdl-23591346

OBJECTIVE: To explore the value of telomerase targeted radiolabeled small interference RNA (siRNA) in tumor imaging in vivo. METHODS: Human telomerase reverse transcriptase (hTERT)-targeted and human gene non-targeted siRNAs were chemically synthesized. Through the conjugation with the chelator N-hydroxysuccinimidyl derivative of S-acetylmercaptoacetyltriglycine (NHS-MAG3), the siRNAs were radiolabeled with technetium-99m ((99m)Tc). HE staining and immunohistochemical staining were used to identify their pathological characteristics. 7.4 MBq of (99m)Tc-siRNAs were injected via the tail vein of hepatocarcinoma bearing mice. At 0.5, 1, 3, and 6 h post injection, the mice were laid on a face-up detector and imaged by single-photon emission computed tomography (SPECT), respectively. The ratio of radioactive counts in tumor to that in the contralateral equivalent region was calculated by drawing regions of interest (ROI) at each time point. After the administration of 7.4 MBq of (99m)Tc-siRNAs, the biodistribution (%ID/g) of tumors and blood was measured at the end of 2, 4 and 6 h. Statistical comparisons of the variables were performed by t-test. RESULTS: The labeling efficiency reached 73.4% ± 3.0%. After purification, the radiochemical purity was no less than 92% and the specific activity was up to 25.9 GBq/µmol. HE staining showed pathological mitotic figure in the nucleus of the tumor cells. hTERT immunohistochemical staining showed deep brown dyed spots in the cell nucleus. hTERT-targeted (99m)Tc-siRNA administrated xenografts showed tumor images clearly after the administration, especially at 6 h. In contrast, (99m)Tc-control-siRNA showed no tumor image. The ratios of uptake in tumor to that in contralateral region of hTERT-targeted siRNA increased from 2.68 ± 0.21 to 5.86 ± 0.30 at 6 h, whereas those of control siRNA decreased from 1.55 ± 0.16 to 1.28 ± 0.12 (P<0.01). The biodistribution of tumors in the hTERT-targeted mice increased from 0.71 ± 0.14 to 0.97 ± 0.15 at 6 h, whereas that in the control mice decreased. CONCLUSION: (99m)Tc radiolabeled telomerase-targeted siRNA probe allows for noninvasive visualization of tumor telomerase in vivo.


Liver Neoplasms, Experimental/diagnostic imaging , RNA, Small Interfering/metabolism , Technetium Tc 99m Mertiatide , Telomerase/genetics , Animals , Female , Isotope Labeling , Liver Neoplasms, Experimental/genetics , Liver Neoplasms, Experimental/metabolism , Mice , Mice, Inbred BALB C , Mice, Nude , Molecular Imaging , Oligonucleotides, Antisense , RNA Interference , RNA, Small Interfering/genetics , RNA, Small Interfering/pharmacokinetics , Radionuclide Imaging , Technetium Tc 99m Mertiatide/pharmacokinetics , Telomerase/antagonists & inhibitors
14.
Nucl Med Biol ; 40(3): 366-70, 2013 Apr.
Article En | MEDLINE | ID: mdl-23312701

INTRODUCTION: When a radiopharmaceutical is simultaneously administered with a medicine that has high affinity for the same plasma protein, the radiopharmaceutical is released at higher concentrations in blood, leading to enhanced transfer into target tissues. This is known as the serum protein binding displacement method. In this study, we investigated the pharmacokinetic alteration of technetium-99m-labeled mercaptoacetylglycylglycylglycine ((99m)Tc-MAG3) using the serum protein binding displacement method. METHODS: Rat and human serum protein binding rates of (99m)Tc-MAG3 were measured by ultrafiltration with or without displacers of human serum albumin (HSA) binding sites I and II (200µM and 400µM loading). Male Wistar rats were injected with (99m)Tc-MAG3 (740kBq/0.3mL saline) via the tail vein, and biodistribution was assessed at 2, 5, 10 and 15min. Dynamic whole-body images were obtained for (99m)Tc-MAG3 (11.1MBq/0.3mL saline)-injected rats, with or without HSA displacers. RESULTS: (99m)Tc-MAG3 strongly bound to HSA (87.37%±2.13%). Using HSA site I displacers, the free fraction of (99m)Tc-MAG3 increased significantly (1.20 to 1.47 times) when compared with controls. For biodistribution and imaging, rapid blood clearance was observed with bucolome (BCL) loading, which is an HSA site I displacer. With BCL loading, peak times for rat renograms were respectively shifted from 240s to 110s, and from 170s to 120s. CONCLUSIONS: We found that (99m)Tc-MAG3 bound to the HSA binding site I. It was confirmed that pharmacokinetic distribution of (99m)Tc-MAG3 is altered by presence of BCL, which leads to increases in the free fraction of (99m)Tc-MAG3, and BCL produced rapid blood clearance and fast peak times on rat renograms. The serum protein binding displacement method using (99m)Tc-MAG3 and BCL, a safe displacer for humans, may be applicable to clinical study and lead to better diagnostic images with shorter waiting times and lower radiation doses for patients.


Serum Albumin/metabolism , Technetium Tc 99m Mertiatide/metabolism , Technetium Tc 99m Mertiatide/pharmacokinetics , Animals , Binding, Competitive , Humans , Male , Protein Binding , Rats , Rats, Wistar , Technetium Tc 99m Mertiatide/administration & dosage
15.
Clin Nucl Med ; 36(11): 1012-6, 2011 Nov.
Article En | MEDLINE | ID: mdl-21975390

PURPOSE: To establish camera-based methods for estimating Tc-99m mercaptoacetyltriglycine (MAG3) clearance without blood sampling. MATERIALS AND METHODS: The results of renal scintigraphy with Tc-99m MAG3 obtained from 160 patients were analyzed retrospectively. Eight renogram parameters were calculated for each patient based on the area under the renogram (area method) and slope of the renogram (slope method) using different periods for analysis (1-2 and 1-2.5 minutes for the area method; 0.5-1.5 and 0.5-2 minutes for the slope method) and different backgrounds for subtraction (perirenal and subrenal backgrounds). The 8 parameters were then correlated with MAG3 clearance measured by the single-sample methods proposed by Russell et al and Bubeck et al to determine the equation for the conversion of renogram parameters to clearance. RESULTS: All 8 renogram parameters were highly correlated with clearance measured by the single-sample methods, and the obtained equations enabled the estimation of clearance from image data. Selection between the area and slope methods, between different periods for analysis, or between perirenal and subrenal backgrounds did not cause large differences in the estimation. CONCLUSION: The camera-based methods determined in the present study allow the estimation of MAG3 clearance with acceptable accuracy.


Blood Specimen Collection/methods , Gamma Cameras , Radioisotope Renography/instrumentation , Technetium Tc 99m Mertiatide/pharmacokinetics , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Kidney/diagnostic imaging , Male , Middle Aged , Young Adult
16.
Ceska Slov Farm ; 60(1): 7-10, 2011 Feb.
Article En | MEDLINE | ID: mdl-21648170

Mercaptoacetyltriglycine (MAG3) and dimercaptosuccinic acid (DMSA) labelled with technetium-99m belongs to standard renal radiodiagnostics. However, the renal transport mechanisms responsible for their high renal uptake have not been fully explained. In addition, no in vitro experimental study comparing the renal uptake of these radiopharmaceuticals at the cellular level has not been performed. The investigation compared the 99mTc-MAG3 and 99mTc-DMSA renal uptake using primary rat renal cells and evaluated contribution of active and passive transport processes to the renal accumulation. The renal cells were isolated from the rat kidneys by means of the two-phase collagenase perfusion method. The used experimental model showed to be useful tool for such type of investigation. The results documented significant quantitative and qualitative differences in the accumulation of 99mTc-DMSA and 99mTc-MAG3 in the rat isolated cells. The found experimental data indicated several times higher uptake of 99mTc-MAG3 than that found in 99mTc-DMSA. 99mTc-MAG3 cellular uptake was substantially decreased when active, energy-dependent processes were inhibited. However, 99mTc-DMSA accumulation in the renal cells demonstrated only a minor dependency on energy. These findings demonstrate a very different character of the membrane transport determining 99mTc-DMSA and 99mTc-MAG3 renal accumulation.


Kidney/metabolism , Radiopharmaceuticals/pharmacokinetics , Technetium Tc 99m Dimercaptosuccinic Acid/pharmacokinetics , Technetium Tc 99m Mertiatide/pharmacokinetics , Animals , In Vitro Techniques , Kidney/diagnostic imaging , Radioisotope Renography , Rats , Rats, Wistar
18.
Urology ; 76(6): 1512-6, 2010 Dec.
Article En | MEDLINE | ID: mdl-20708778

OBJECTIVES: To address the fact that a decrease in the relative renal uptake of 99mTc-mercaptoacetyltriglycine (MAG3) on serial MAG3 scans may indicate a loss of function and require a change in management by providing guidance as to what constitutes a meaningful change in serial relative function measurements as well determining the normal variation of other common MAG3 renogram parameters. METHODS: A prospective study was conducted in 24 male urology patients with stable renal function. The mean age was 66.5 ± 7.9 (SD) years; the mean serum creatinine was 1.38 ± 0.57 (SD) mg/dL, and the MAG3 renal scans were performed a mean of 11 ± 8 days apart. Each MAG3 scan included a measurement of relative function as well as the time to maximum counts and 20 minutes to maximum count ratios for both cortical and whole kidney regions of interest. RESULTS: The Pearson and intraclass correlations for the baseline and repeat measurements of relative renal function were both 0.98. Bland-Altman plots showed no bias between the baseline and repeat relative uptake measurements. The mean difference between 2 repeated measurements of the relative MAG3 uptake was 0.04 ± 2.88% (SD) for the left kidney and 0.08 ± 3.07% (SD) for the right kidney. Comparable results were obtained for the other renogram parameters. CONCLUSIONS: Measurements of relative renal uptake of MAG3 and common renogram parameters are highly reproducible; a decrease in relative uptake ≥7% (ie, 50%-43%) implies a loss in renal function.


Kidney Function Tests/methods , Kidney/diagnostic imaging , Radiopharmaceuticals/pharmacokinetics , Technetium Tc 99m Mertiatide/pharmacokinetics , Aged , Creatinine/blood , Humans , Kidney/metabolism , Male , Middle Aged , Prospective Studies , Radionuclide Imaging , Reproducibility of Results , Ureteral Obstruction/diagnostic imaging
19.
In Vivo ; 24(2): 137-9, 2010.
Article En | MEDLINE | ID: mdl-20363984

Renal function measurements using (99m)Tc-DTPA and (99m)Tc-MAG(3) dynamic scintigraphs were compared to those obtained using (99m)Tc-DMSA static scintigraphy. Eighteen experimental rabbits were randomly divided into (99m)Tc-DTPA-, (99m)Tc-MAG(3)-, and (99m) Tc-DMSA-injected groups. Experimental unilateral renal damage was induced by ligating a unilateral right ureter in 18 rabbits. Scintigraphic images were obtained at 2 and 5 h after intravenous injection of (99m)Tc-DMSA, or immediately after administration of (99m)Tc-DTPA or (99m)Tc-MAG(3). For the dynamic images using (99m)Tc-DTPA and (99m)Tc-MAG(3), rapid sequential images were obtained every 2 s for 30 images up to 1 min. The three groups presented different relative renal functions between the left normal and the right abnormal kidneys at 1, 2, 3, and 4 weeks post-ligation (p<0.05). However, the between-group comparisons showed no significant differences at any time. These results suggest that dynamic images of (99m)Tc-DTPA and (99m)Tc-MAG(3) can be used to measure the relative renal function in place of the static image of (99m)Tc-DMSA.


Kidney/metabolism , Radiopharmaceuticals , Technetium Tc 99m Dimercaptosuccinic Acid , Technetium Tc 99m Mertiatide , Technetium Tc 99m Pentetate , Ureteral Obstruction/diagnostic imaging , Animals , Kidney Function Tests/methods , Male , Rabbits , Radionuclide Imaging , Radiopharmaceuticals/pharmacokinetics , Technetium Tc 99m Dimercaptosuccinic Acid/pharmacokinetics , Technetium Tc 99m Mertiatide/pharmacokinetics , Technetium Tc 99m Pentetate/pharmacokinetics
20.
Bioorg Med Chem Lett ; 20(1): 315-7, 2010 Jan 01.
Article En | MEDLINE | ID: mdl-19926278

Three carbohydrate derivatives, MAG(3)-Gl, MAG(3)-Ga, MAG(3)-NG, were synthesized and radiolabeled in high yields. These substances were injected in health Swiss mice and their biodistribution were evaluated. Among them, (99m)Tc-MAG(3)-Ga displayed higher accumulation in hepatic tissue, due to the presence of specific receptors in the liver for this carbohydrate. Thus, the use of (99m)Tc-MAG(3)-Ga to assess hepatic function can be considered.


Carbohydrates/chemistry , Technetium Tc 99m Mertiatide/chemistry , Animals , Carbohydrates/chemical synthesis , Carbohydrates/pharmacokinetics , Glycine/analogs & derivatives , Glycine/chemistry , Glycine/pharmacokinetics , Isotope Labeling , Liver/metabolism , Mice , Technetium Tc 99m Mertiatide/pharmacokinetics , Tissue Distribution
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