Trombosis vascular en injerto renal visualizado en renograma con 99mtc - mag3, un evento infrecuente / Vascular thrombosis in renal graft visualized in 99mtc- mag3 renogram, in unfortunate event / Trombose vascular do enxerto em renal renogram exibido em 99m - mag3, um evento pouco freqüente

El trasplante renal es el tratamiento de elección para la enfermedad renal terminal. Pueden presentarse diversas complicaciones médicas y quirúrgicas posteriores, entre ellas las vasculares (trombosis/estenosis de la vena y/o arteria renal) que son poco frecuentes y resultan en la pérdida del injerto. Presentamos el caso de un paciente masculino que al tercer día posterior al trasplante persisten con anuria y elevación de azoados, realizándose renograma con 99m - Tc MAG3 con hallazgos compatibles de trombosis vascular.

Kidney transplantation is the treatment of choice for end-stage renal disease. Various medical and surgical complications can occur later, among them the vascular ones (thrombosis/stenosis of the vein and/or renal artery) that are infrequent and result in the loss of the graft. We present the case of a male patient who persisted with anuria and azoate elevation on the third day after transplantation, performing a renogram with 99m - Tc MAG3 with compatible findings of vascular thrombosis.

Formulation of lyophilized single vial kit of N-N-Ethylene-L-Dicysteine 99m [EC] for labeling with Tc. II: Radiochemical and clinical evaluation 99mr as a renal tubular agent in comparison with Tc-MAG[3]

A Technetium[99m]Tc 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 bio distribution 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[99m]Tc-EC at pH 8 in 12 volunteers and at pH 10 in 18 volunteers and compared with[99m]Tc-MAG[3], Background ratios, renograms, relative renal function and semi quantitative parameters are available in all studies. The background ratios [mean +/- SD] at 30[th] minute are 0229+/-0.024 and 0.236+/-0.018 for[99m]Tc-EC at pH 10 and[99m]c-MAG[3] respectively. The mean +/- standard error of mean [SEM] values of T[M]X and time to half activity [T[12]] for[99m]Tc-EC [pHIO] are 3.7+/-0.6 and 7.3+/-1.0 respectively while for [99m]Tc-MAG[3], 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[99m]Tc-EC and[99m]Tc-MAG[3] are 50.8+/-3.11 and 51.2+/-3.4 respectively with p value of 0.822. The residual activity at 25[th] minute [A[25] / A[MAX]] and renal uptake are 0. 209+/-12.67+/-2.80 for[99m]Tc-EC and 0.218+/-0.035 and 1053+/-2.98 for[99m]Tc-MAG[3] [p=0.031 an 0.0003] respectively. The correlation coefficient [R] for T[max], T1/2, A[2]5/A[Max] and renal uptake are 0.96, 0.69, 0.93 and 0.85 respectively

Glomerular Filtration Rate Measurements Using 99mTechnetium-mercaptoacetyltriglycine Dynamic Renal Scintigraphy in Children with Renal Disease

PURPOSE: In children, 24-hour urine collections are unreliable for evaluating glomerular filtration rate (GFR) because of the difficulty of regulating voiding and the daily variation of urinary creatinine up to 25%. Additionally, creatinine clearance (Ccr) based on urinary creatinine is considered inaccurate. The purpose of this study was to compare estimated GFR determined using Ccr, formulas with serum cystatin C and creatinine, and 99mTc-mercaptoacetyltriglycine (MAG3) dynamic renal scintigraphy. METHODS: This retrospective study included 101 patients (age, <18 years) who visited Chung-Ang University Hospital between July 2011 and August 2012. GFR was estimated using 24-hour urinary creatinine, five formulas with serum creatinine and cystatin C, and 99mTc-MAG3 renal scan. RESULTS: Of the 101 patients, glomerular renal diseases were present in 60 patients (59.4%) and non-glomerular diseases were present in 41 patients (40.6%). There was a significant correlation between estimated GFR determined using 99mTc-MAG3 renal scan and Ccr (r=0.389, P<0.001). The correlation values between estimated GFR determined using 99mTc-MAG3 renal scan and each formula of Schwartz, Counahan-Barratt, Cockcroft-Gault, Filler and Lepage, and Bokencamp were 0.265 (P=0.007), 0.128 (P=0.044), 0.230 (P=0.021), 0.356 (P<0.001), and 0.355 (P<0.001), respectively. 99mTc-MAG3 renal scan was correlated with estimated-GFR by all formulas in decreased renal function. CONCLUSION: Estimated GFRs determined using serum creatinine and cystatin C, and 99mTc-MAG3 renal scan correlated well with estimated GFR determined using Ccr. 99mTc-MAG3 renal scan may be replaced for evaluation of renal function with convenience in patients with renal disease and decreased renal function in childhood.

Diagnostic Criteria for Stomal Obstruction of Tubeless Cutaneous Ureterostomy by Use of 99mTc-Mercaptoacetyltriglycine Diuretic Renography

PURPOSE: To evaluate 99mTc-mercaptoacetyltriglycine diuretic renograms for diagnosing stomal obstruction in tubeless cutaneous ureterostomy. MATERIALS AND METHODS: Cutaneous ureterostomy was performed in 29 patients (56 renal units) with a minimum follow-up period of 12 months. Stomal obstruction was evaluated with 99mTc-mercaptoacetyltriglycine diuretic renography 3 months after surgery. Regions of interest were drawn that completely encircled and snugly fit the kidney, renal pelvis, and ureter. The data analyses were performed with half-times to tracer clearance following furosemide (0.5 mg/kg) administration. RESULTS: The mean half-times to tracer clearance were 6.90+/-6.30, 5.25+/-4.29, and 8.75+/-7.63 minutes in the total, ipsilateral, and contralateral kidneys, respectively, in side relationships between the ureter and the stoma. There were significant differences between the ipsilateral and contralateral kidneys in the mean half-time to tracer clearance (p=0.038). Forty-eight renal units (85.7%) had a half-time to tracer clearance of less than 15 minutes, and all 48 renal units had no hydronephrosis. On the other hand, 5 renal units (8.9%) had a half-time to tracer clearance of more than 20 minutes, and these 5 renal units required the insertion of stent catheters or became atrophic. CONCLUSIONS: 99mTc-mercaptoacetyltriglycine diuretic renography was very useful for diagnosing stomal obstruction of tubeless cutaneous ureterostomy. The upper limit of the half-time to tracer clearance for unobstructed systems was 15 minutes, which allowed for the confident exclusion of stomal obstruction in tubeless cutaneous ureterostomy.

Difference in Results of Ultrasonography and Diuretic Renograms after Pyeloplasty in Children with Unilateral Ureteropelvic Junction Obstruction

PURPOSE: Controversies persist on pyeloplasty follow-up, and the aim of this study was to assess the differences and interpretations in results of postoperative ultrasonography and diuretic renograms. MATERIALS AND METHODS: The study population consisted of 46 patients who underwent pyeloplasty between 1997 and 2003. The average patient age was 7.0 months (range, 2-36 months). Serial changes in hydronephrosis were evaluated by consecutive ultrasonography at 1, 4, 10, and 24 months after pyeloplasty, and a diuretic 99mTc-MAG3 renal scan was performed 4 months after the surgery. RESULTS: Ultrasonography showed that 11 (24%), 27 (59%), 35 (76%), and 39 (89%) patients had improved in hydronephrosis at 1, 4, 10, and 24 months after pyeloplasty, respectively. Diuretic renal scans showed that of 27 patients who showed improvements in hydronephrosis at 4 months after pyeloplasty, only 17 (63%) had improved excretion and 22 (81%) had preservation of different renal function (DRF). Among 19 patients with persistent or worsened hydronephrosis, 10 (53%) had improved excretion and 13 (68%) had preserved DRF. CONCLUSIONS: The results of ultrasonography and diuretic renal scan studies can differ in the same case after pyeloplasty. We recommend that improvements in hydronephrosis be assessed individually by ultrasonography, renal scans, and clinical status to determine surgical outcomes.

Preparation and quality control of 99mTc labeled MDR1 oligonucleotide DNAs / 生物医学工程学杂志

The aim of this study is to explore the optimal labeling condition of technetium-99m labeled antisense oligonucleotides (ASON) DNA and sense oligonueleotides (SON) DNA against multi-drug resistance gene-1 (MIDR1) mRNA, to prepare its two-step icefrozen kits, and to perform the quality control of technetium-99m labeled ASON and SON DNAs and its two-step icefrozen kits. A 20 mer single-stranded ASON sequence and its SON sequence against MDR1 mRNA were synthesized respectively, both of the ASON and SON DNAs were uniform phosphorothioated for this investigation with a primary amine on the 5'-end via a six-carbon alkyl linker, and then were labeled with technetium-99m by conjugating with the bifunctional chelator S-Acetyl NHS-MAG3 to form ASON- and SON-MAC3 DNAs. The optimal labeling condition was explored by varying the amount of ASON- and SON-MAG3 DNAs, SnCl2.2H2O and buffer, the pH value in the reaction medium was also adjusted. The technetium-99m labeled ASON and SON DNAs' two-step icefrozen kits were developed. The radiochemical purities, labeling stability of ASON- and SON-MAG3 DNAs in vivo and vitro were measured, and stability of the two-step icefrozen kits were also studied. The recycled rates of ASON- and SON-MAG3 DNAs were over 70% (n >6), the two-step icefrozen kits of ASON- and SON-MAG3 DNAs were colourless ice crystal. The radiochemical purities of technetium-99m labeled ASON- and SON-MAG3 DNAs were over 92 %. The radiochemical purities were over 90% after stored at room temperature for 24 hours. The kits were stable within 6 months when stored at 0 degrees C, the radiochemical purities of technetium-99m labeled ASON- and SON-MAG3 DNAs were still over 90%. The two-step icefrozen kits of ASON- and SON-MAG3 DNAs were successfully developed. The radiochemical purities were all over 90%. The labeling method was simple, feasible and efficient with good stability.

A comparison on radiochemical behavior and biological property of antisense oligonucleotide labeled with technetium-99m by two methods: NHS-MAG3 versus SHNHP / 生物医学工程学杂志

This study was undertaken to explore and compare the radiochemical behavior and biological property of antisense oligonucleotide (ASON) labeled with Technetium-99m using two methods: N-hydroxysuccinimidyl S-acetylmercaptoacetyltriglycline (NHS-MAG3) versus hydrazino nicotinamide derivative (SHNH). After SHNH and NHS-MAG3 were synthesized, ASON was labeled with Technetium-99m using SHNH and NHS-MAG3 as a bifunctional chelator, separately. The stability in vivo and in vitro, the combination with plasma albumen of rabbit, the biodistribution in BALB/ C mice and the HT29 cellular uptake were compared between labeled compound 99mTc-SHNH-ASON, using SHNH as a bifunctional complex reagent, and 99mTc-MAG3-ASON, using NHS-MAG3 as a bifunctional chelator. The results revealed that the labeling rate and the stability of 99mTc-MAG3-ASON were evidently higher than that of 99mTc-SHNH-ASON (P < 0.05), the combination rate of 99mTc-MAG3-ASON with plasma albumen was markedly lower than that of 99mTc-SHNH-ASON (P < 0.05); the biodistribution of 99mTc-MAG3-ASON was markedly lower than that of 99mTc-SHNH-ASON in blood, heart, stomach and intestines (P < 0.05), slightly lower than that of 99mTc-SHNH-ASON in liver and spleen (P > 0.05), and markedly higher than that of 99mTc-SHNH-ASON in kidney (P < 0.05); the HT29 cellular uptake rates of 99mTc-MAG3-ASON was markedly higher than that of 99mTc-SHNH-ASON (P < 0.05). Therefore, the radiochemical behavior and biological property of 99mTc-MAG3-ASON labeled using NHS-MAG3 is better than that of 99mTc-SHNH-ASON labeled using SHNH.

(99m)Tc-YIGSR as a receptor tracer in imaging the Ehrlich ascites tumor-bearing mice as compared with (99m)Tc-MIBI / 华中科技大学学报（医学）（英德文版）

The validity of (99m)Tc-YIGSR, a novel receptor radio-tracer, in imaging the Ehrlich ascites tumor was evaluated. YIGSR, a pentapeptide of laminin, was labeled with (99m)Tc by using a bifunctional chelator S-Acetly-NH(3)-MAG(3). The MIBI was labeled with (99m)Tc by following the kit instruction. The mice of tumor group were intravenously injected 1-2 mCi of (99m)Tc-YIGSR or (99m)Tc-MIBI via caudal vein, immobilized and imaged under a Gamma camera. The same procedure was performed in mice of blockade group, in which the unlabeled YIGSR was previously injected to block the receptor-recognition sites, and inflammation group serving as control. The reverse-phase Sep-Pak C(18) chromatogram was found to have an essentially complete conjugation between YIGSR and S-Acetly-NH(3)-MAG(3). The conjugated YIGSR could be radio-labeled successfully with (99m)Tc at room temperature and neutral pH, with a radio-labeling yield of 62%. Without the chelator S-Acetly-NH(3)-MAG(3), the YIGSR was labeled with (99m)Tc at an efficiency of 4%. The imagological study revealed obvious tumor accumulation of (99m)Tc-YIGSR 15 min after the injection, and the uptake peaked after 3 h with a tumor-to-muscle ratio (T/M) of 11.36. The radio-tracer was slowly cleared up and resulted in a T/M of 3.01 at the 8th h after the injection. As for blocked group, the tumor uptake of radiotracer was significantly lower, with the highest T/M being 4.61 after 3 h and 0.89 after 8 h. The T/M was 3.72 at the 3rd h and 1.29 at the 8th h after the (99m)Tc-YIGSR injection in the inflammatory group. The T/M was significantly higher in tumor group than in inflammatory group or control group (P<0.001). In the 99mTc-MIBI group, the T/M was 1.40 at the 3rd h and 0.55 at the 8th h after the injection, which showed a significant difference as compared with (99m)Tc-YIGSR (P<0.001). It is concluded that YIGSR can be successfully radiolabelled by using S-Acetly-NH(3)-MAG(3). (99m)Tc-YIGSR has many advantages in tumor imaging, such as quick and clear visualization, high sensitivity and specificity, and satisfactory target/non-target ratio (N/NT). It promises to be tumor radio-tracer.

(99m)Tc-YIGSR as a receptor tracer in imaging the Ehrlich ascites tumor-bearing mice as compared with (99m)Tc-MIBI / 华中科技大学学报（医学）（英德文版）

The validity of (99m)Tc-YIGSR, a novel receptor radio-tracer, in imaging the Ehrlich ascites tumor was evaluated. YIGSR, a pentapeptide of laminin, was labeled with (99m)Tc by using a bifunctional chelator S-Acetly-NH(3)-MAG(3). The MIBI was labeled with (99m)Tc by following the kit instruction. The mice of tumor group were intravenously injected 1-2 mCi of (99m)Tc-YIGSR or (99m)Tc-MIBI via caudal vein, immobilized and imaged under a Gamma camera. The same procedure was performed in mice of blockade group, in which the unlabeled YIGSR was previously injected to block the receptor-recognition sites, and inflammation group serving as control. The reverse-phase Sep-Pak C(18) chromatogram was found to have an essentially complete conjugation between YIGSR and S-Acetly-NH(3)-MAG(3). The conjugated YIGSR could be radio-labeled successfully with (99m)Tc at room temperature and neutral pH, with a radio-labeling yield of 62%. Without the chelator S-Acetly-NH(3)-MAG(3), the YIGSR was labeled with (99m)Tc at an efficiency of 4%. The imagological study revealed obvious tumor accumulation of (99m)Tc-YIGSR 15 min after the injection, and the uptake peaked after 3 h with a tumor-to-muscle ratio (T/M) of 11.36. The radio-tracer was slowly cleared up and resulted in a T/M of 3.01 at the 8th h after the injection. As for blocked group, the tumor uptake of radiotracer was significantly lower, with the highest T/M being 4.61 after 3 h and 0.89 after 8 h. The T/M was 3.72 at the 3rd h and 1.29 at the 8th h after the (99m)Tc-YIGSR injection in the inflammatory group. The T/M was significantly higher in tumor group than in inflammatory group or control group (P<0.001). In the 99mTc-MIBI group, the T/M was 1.40 at the 3rd h and 0.55 at the 8th h after the injection, which showed a significant difference as compared with (99m)Tc-YIGSR (P<0.001). It is concluded that YIGSR can be successfully radiolabelled by using S-Acetly-NH(3)-MAG(3). (99m)Tc-YIGSR has many advantages in tumor imaging, such as quick and clear visualization, high sensitivity and specificity, and satisfactory target/non-target ratio (N/NT). It promises to be tumor radio-tracer.

Correlation of the ERPF with the extraction fraction values of technetium-99m mercaptoacetyltriglycine.

OBJECTIVE: The objective of this study was to determine if a correlation exists between the effective renal plasma flow (ERPF) and the extraction fraction (EF) using 99mTc MAG3 in children. This EF has been previously described with 9mTc DTPA. However, the renal imaging agent of choice has become 9mTc MAG3. MATERIAL AND METHOD: The study was approved by The Children's Hospital of Philadelphia's institutional review board. Informed consent was also obtained A retrospective study of 29 children (16 males, 13 females) of ages 1 month to 19.5 years who underwent 99mTc MAG3 renal scintigraphy from September 2001 to December 2001 was analysed. EF values were calculated with and without attenuation correction in each kidney by determining the counts in a region of interest, correcting for background and comparing the counts with the injected dose. The EF was compared to the ERPF calculated using the Schlegel's method. The correlation between the EF and the ERPF corrected and non-corrected for soft tissue attenuation, were determined and were identified by using linear regression analysis. RESULTS: There was significant correlation between the ERPF and the EF with (r = 0.62, p < 0.05 on the left, r = 0.51, p = 0.005 on the right) than without attenuation correction (r = 0.54, p = 0.003 on the left, r = 0.42, p = 0.022 on the right). CONCLUSION: These results indicate a correlation of the ERPF calculated using the Schlegel's method with EF obtained from a 99mTc MAG3 renal scintigraphy. The EF may be the good alternative parameter for calculation of renal function, potentially more practical in pediatric patient and the ERPF for 99mTc MAG3 using the established software program based on Schlegel's formula.

Dificultades en la interpretación del renograma diurético en niños / Difficulties in the interpretation of diuretic renal scintigraphy in childrens

El renograma diurético continúa siendo el estudio funcional de carácter no invasivo de elección en la evaluación de pacientes con hidronefrosis y probable obstrucción pielo-ureteral. Para una adecuada interpretación de éste es esencial dar una meticulosa atención a factores como la preparación previa del paciente, la selección del radiofármaco, la dosis y administración del diurético, la interpretación de las imágenes y el conocimiento de los potenciales errores de la técnica. Para la mayoría de los pacientes el protocolo F+20 es suficiente, sin embargo el protocolo F-15 puede ayudar a clarificar los casos equívocos del protocolo F+20. Las técnicas invasivas como el test de Whitaker son reservadas para aquellos pacientes con hidronefrosis severa o con insuficiencia renal en donde el diagnóstico clínico aún persiste equívoco después de haber efectuado el renograma. Las recientes publicaciones de guías de protocolos estandarizados y consensos internacionales han contribuido a unificar criterios y así mejorar la agudeza diagnóstica y la reproducibilidad de la técnica.

Laparoscopic Pyeloplasty with Transperitoneal Approach for Ureteropelvic Obstruction / 대한비뇨기과학회지

PURPOSE: Laparoscopic pyeloplasty is an alternative, minimally invasive approach for the repair of an ureteropelvic junction obstruction (UPJO). However, it has a technical difficulty, and various laparoscopic approaches are available. We present our initial experience of laparoscopic pyeloplasty using a transperitoneal approach in patients with an UPJO. MATERIALS AND METHODS: Between January 2002 and January 2004, 11 patients underwent laparoscopic pyeloplasty using a transperitoneal approach. Of these 11, 10 patients were followed up and enrolled in this study. They were comprised of 6 males and 4 females, with a mean age of 44 years (19-62). The chief complaints were flank pain in 8 patients, with a further 2 incidental detected. Three patients had had previous abdominal surgeries. The mean length of stricture was 1.1cm in the radiologic studies, and the degree of hydronephrosis was grade 3/4 in 6 patients and grade 4/4 in 4. An obstructive pattern in the 99mTc-MAG3 renal scan was present in 9 patients. RESULTS: Eight patients were treated with dismembered Anderson-Hynes pyeloplasty and 2 patients with Fenger pyeloplasty. The mean operating time and hospital stay were 225 minutes (120-450) and 7.4 days (5-10), respectively. During the operation, crossing vessels were found in 4 patients and an ureteral polyp in 1. One patient had an ascending colon injury, which was postoperatively detected and repaired. The mean follow- up period was 42.5 weeks (26-135). Follow-up excretory urography and a 99mTc-MAG3 renal scan showed improvements in 8 of the 10 patients (80%) at the 3 month follow-up. The flank pain disappeared in all the patients (100%) who had previously complained of this symptom. CONCLUSIONS: Laparoscopic pyeloplasty could be an alternative treatment for an ureteropelvic junction obstruction, especially using a transperitoneal approach, which seems to have a technical convenience over that of the retroperitoneal approach.

An imaging study using laminin peptide 99mTc-YIGSR in mice bearing Ehrlich ascites tumour / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The YIGSR is a pentapeptide, from the laminin-1 of the beta1 chain, which can mediate cell adhesion and bind the 67 kD laminin receptor. The purpose is to evaluate the usefulness of (99m)Tc-YIGSR, a novel tumour radiotracer, in the receptor imaging of Ehrlich ascites tumour.</p><p><b>METHODS</b>Using S-acetly-NH3-MAG3 as chelate, YIGSR, a pentapeptide from laminin, was tagged with (99m)Tc. (99m)Tc-YIGSR was detected in the tumour group bearing Ehrlich ascites tumour and blocked group. Tumour, normal, inflammatory and blocked groups were imaged.</p><p><b>RESULTS</b>Through reverse phase Sep-Pak C18 chromatogram, it was revealed that YIGSR could conjugate with S-acetly-NH3-MAG3, and be radiolabelled at room temperature and neutral pH with a radiolabelling yield of 62%, and of 4% without chelate. (99m)Tc-YIGSR was rapidly cleared from kidney, then liver. The imaging findings showed tumour tissue accumulated initial radioactivity at fifteen minutes after injection in the tumour group, and the uptake increased to peak at three hours with a tumour/muscle ratio (T/M) of 11.36, then cleared slowly to a T/M of 7.50 at eight hours. The tumour uptake of radiotracer in blocked group was significantly lower with T/M of 4.61 at three hours and 0.89 at eight hours. The T/M was only 3.72 at three hours and 1.29 at eight hours after injection in inflammatory group. Compared with inflammatory group and control obstructive group, the ratio of T/M in tumour group was significantly different (P < 0.001).</p><p><b>CONCLUSIONS</b>Using S-acetly-NH3-MAG3, we radiolabelled YIGSR with (99m)Tc. (99m)Tc-YIGSR possesses many merits of tumour imaging: rapid visualization, high sensitivity and specificity, and satisfactory target/nontarget ratio. Our data suggest (99m)Tc-YIGSR is a promising tumour radiotracer.</p>

A comparative study of 99mTc-YIGSR and 99mTc-MIBI uptake in tumor cells / 华中科技大学学报（医学）（英德文版）

To investigate a new kind of tumor tracer 99mTc-YIGSR developed from a five amino structure (YIGSR) of the Laminin -chain, which can bind to the laminin receptors of tumor specifically, and radiolabeled with MAG3. (1) Preparation of the 99mTc-YIGSR probe: with S-Acetly-NH3-MAG3 as the chelator and with proper reductants YIGSR was labeled with 99mTc; (2) Cell culture and viability measurement: EAC was maintained in RPMI 1640 supplemented with calf serum; the trypan blue exclusion was applied to calculate the cell viability; (3) Study of the cell dynamic: The EAC's uptake of 99mTc-YIGSR and 99mTc-MIBI was observed at 37 degrees C and 22 degrees C, respectively. (1) The labeling efficiencies of 99mTc-YIGSR and 99mTc-MIBI were (62 +/- 3)% and (96 +/- 2)%, respectively; (2) The cell viability was declined with time of incubation; (3) At 37 degrees C, the EAC'S uptake of 99mTc-YIGSR and 99mTc-MIBI reached the peak of (43.16 +/- 2.4) % and (24.4 +/- 1.8) % at 60 min, respectively; and at 22 degrees C, the highest uptake was (26.5 +/- 2.1) % and (9.47 +/- 1.9) % at 60 min, respectively. The in vitro study suggests that 99mTc-YIGSR is superior to 99mTc-MIBI in cell uptake and has potential value in tumor imaging.

Purificación del benzoil-mercaptoacetil triglicina, complementado con evaluaciones biológicas / Purification of benzoil-mercaptoacetil triglicine, complemented with biological evaluations

La síntesis se realiza por la técnica de W. Brandau. La purificación se realizó por cristalización fraccionada en metanol: agua (80:20), monitoreada por HPLC. Se obtienen varios precipitados, con los cuales se preparan minilotes de prueba, que se marcan con Tc 99m y se realizaron los controles radioquímicos y las evaluaciones biológicas. Los resultados obtenidos son los siguientes: la pureza química del Bz-MAG3 se incrementa de un 70 por ciento a un 98,12 por ciento del compuesto activo, con un rendimiento del 25 por ciento aproximadamente; la pureza radioquímica de los precipitados puros es mayor del 98 por ciento y el porcentaje de dosis de inyección en riñones se incrementa de un 8 por ciento a un 30 por ciento a los 5 minutos post-inyección en ratones sanos. El porcentaje de excreción renal promedio a los 60 minutos es mayor del 90 por ciento, porcentaje que garantizará una buena calidad de imágenes gammagráficas renales.

Análogos de somatostatina marcados con 99m-TC / Somatostatine analogs marked with 99m-TC

El objetivo del presente trabajo es el estudio biológico y radioquímico de dos análogos de la somatostatina, el péptido RC-160 y el Tyr3-Octreotide (TOC), marcados con 99mTc por método directo e indirecto usando como quelantes mercapto acetil triglicina (MAG3) e hidrazinonicotinamida (HYNIC) respectivamente. Se realizó la síntesis del benzoil MAG3-RC-160 y del HYNIC-Tyr3-Octreotide los cuales se marcaron con 99mTc obteniéndose purezas radioquímicas mayor que 70 por ciento y mayor que 95 por ciento respectivamente. Se realizaron biodistribuciones en ratas Wistar normales y los resultados se correlacionaron con los datos cromatográficos y de unión a proteinas, encontrándose que a menor lipofilicidad de los complejos se incrementaba la excreción renal. Se realizaron ensayos de unión a receptores utilizando como fuente de los mismos membranas de corteza de cerebro de rata. Los mejores resultados se obtuvieron con el conjugado de HYNIC-TOC marcando con tricina como coligando

Reflux Nephropathy Detected by Post-voiding Image on Scintigraphic Tc-99m MAG3 Scan

99mTc-MAG3 Scintigraphic Scan is sensitive at depicting focal parenchymal abnormalities and can be used for the measurement of overall renal function. We experienced a 12-year-old girl presenting with fever and flank pain. On the ultrasonogram and post-voiding delayed image of 99mTc-MAG3 scintigraphic scan, severe right cortical atrophy and hydronephrosis with vesicoureteral reflux were detected. We could demonstrate the reflux nephropathy by these two diagnostic work-up without conventional voiding cystourethrography.

99mTc MAG3 and 99mTc DTPA; comparison to evaluate renal functions in renal transplant patients

Renal scintigraphy evaluates the renal function non-invasively. The present study was conducted to compare 99mTc MAG3 and 99mTc DTPA in renal transplant patients for the evaluation of renal functions. Materials and 99mTc MAG3 and 99mTc DTPA studies were performed on 33 renal transplant patients and 10 normal subjects, with 1 day interval in between the two studies. Renal transplant patients were categorized as normal, acute tubular necrosis, rejection, urine outflow obstruction and urinary tract infection groups on the basis of routine clinical investigations and preliminary results of scintigraphic studies. Both radiopharmaceuticals, 99mTc MAG3 and 99mTc DTPA were having equal diagnostic efficacy, however image quality with 99mTc MAG3 was superior to that of 99mTc DTPA. Renograms clearly differentiated various renal groups. Correlation between glomerular filtration rate [GFR] and effective renal plasma flow [ERPF] was good [r=0.89 at P<0.00001]. In terms of perfusion index [PI] our results with both agents were similar [r=0.96 at p<0.00001], clearly differentiating all cases of rejection from acute tubular necrosis. PI was raised in rejection cases, while normal in all other groups. In cases of acute tubular necrosis and rejection, 99mTc MAG3 based parenchymal retention index [R-20/3] was markedly raised, compared to that of 99mTc DTPA [p<0.00001]. 99mTc- MAG3 and 99mTc DTPA have equal diagnostic efficacy in renal transplant patients. However visual delineations of the kidneys is better with 99mTc MAG3, especially in cases with compromised renal functions

Utilidad de la gamagrafía renal con MAG3 en evaluación de disfunción posterior al trasplante / Utility of renal gammagraphy with MAG3 in the evaluation of post transplantation disfunction

La evaluación de riñones trasplantados se puede realizar por medio de la gamagrafía renal con mercaptoacetiltriglicina (MAG3) marcada con tecnecio 99. Tulchinsky y colaboradores diseñaron la escala de severidad de injuria tubular (TISS) (utilizando MAG3) para evaluar la magnitud del compromiso funcional y determinar la posibilidad de recuperación renal. Objetivo: El presente estudio tuvo por objeto aplicar la escala del TISS a pacientes con diagnóstico de disfunción temprana (primeras 72 horas posterior al transplante) para establecer el pronóstico de recuperación; la capacidad de predicción fue evaluada por seguimiento clínico. Lugar del estudio: Fundación Clínica Valle del Lili, Cali - Colombia Materiales y Métodos: Se evaluaron 20 pacientes con sospecha de disfunción temprana, se aplicó la escala de TISS; se clasificaron en dos grupos: aquellos que recuperaron la función y quienes la perdieron. Se cálculo la concordancia entre observadores al aplicar la escala. Resultados: Los pacientes con disfunción temprana se clasificaron así: TISS 1:4, 2:5, 3:4, 4:3, 5:1 y 6:3. Del grupo total, 14 recuperaron la función y 6 perdieron el trasplante; todos los pacientes con TISS 1 evolucionaron a recuperación de la función y los TISS 6 a pérdida renal. Se encontraron mayores pérdidas en pacientes con escala ü a 4: 85 por ciento vs 16por ciento (p= 0.0012). El grado de acuerdo entre observadores al aplicar la escala de TISS fue 90 por ciento y el estadístico kappa del 0.80. Conclusiones: La importancia de la gamagrafía con MAG3 radica no sólo en la utilidad diagnóstica sino pronóstica; ésta última se puede determinar mediante la aplicación de la escala de TISS, sin embargo se requiere validación con un mayor número de pacientes