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Sample records for 99m technetium labeled

  1. 99mTechnetium labelled Escherichia coli

    Samples of a culture of unlabeled Escherichia coli were incubated with different concentrations of stannous chloride for various time periods. 99mTc (26.0 MBq) was added to each preparation and the results showed a labelling yield of 98% for E. coli. Since the bacterial viability of 99mTc-E. coli and E. coli did not show any statistical differences, these results demonstrate that labelling of E. coli with 99mTc does not modify the bacterial viability, and the radiolabelled bacteria may be a good model to study bacterial translocation

  2. Studies of labelling of melphalan with technetium-99m

    Melphalan is an alkylating agent widely used in the treatment of neoplastic diseases. However, being an α-amino acid it cannot be labeled with Tc-99m by the use of SnCl2 for pertechnetate reduction. The N-carboxy methyl - derivative of melphalan was obtained and its complexing by technetium-99m was examined. A procedure for labelling of melphalan derivative with Tc-99m has been developed. (author). 18 refs, 8 figs, 8 tabs

  3. Labelling of biological structures with technetium 99 m

    The labelling of red blood cells (RBC) with technetium 99m (99m Tc) depends on several factors, as the stannous ion (Sn++) concentration, the time and temperature of incubation, the anticoagulant utilized, the presence of plasma proteins (PP) and others. Although the blinding of 99m Tc with hemoglobin and PP are similar, they appear to have specific characteristics as demonstrated by precipitation with alcohol, acetone, trichloroacetic acid, hydrochloric acid and mercury chloride. The bacterial cultures labeled with Technetium-99m, at optimal Sn++ ion concentration, presents a large stability and their viability is not altered by this treatment. The electrophoretic mobility, the hydrophobicity, the cationized ferritin distribution and the adherence to human buccal epithelial cells are not modified either. The possibility of labelling with 99m Tc of planaria and cercariae of Schistossoma mansoni evaluative cycle increases the utilization of this radionuclide to an experimental level. The results described with the labelling of these biological structures with 99m Tc demonstrated that stable labeled and viable operations are obtained. (author)

  4. The radio-labeling of Ciprofloxacin with Technetium-99m

    Even with rapid technological development in the field of diagnostic imaging, the localization of infection continues to pose challenges in day-to-day routine clinical practice. Tc-99m Ciprofloxacin is a relatively new radiopharmaceutical, which has proven its utility in imaging infection. This paper presents a new method of labeling Ciprofloxacin with Tc-99m using SnCI2.2H20 as reducing agent. The procedure used 2 mg of Ciprofloxacin manufactured by Bayer, 400 μg of SnCI2.2H20 (Sigma Chemical Co.) and 185MBq of Technetium-99m in the form of pertechnetate (Tc-99mO4) in a volume of 300 μl. The labeling was carried out at 100 deg. C for 10 minutes and at ambient temperature for a similar period of time. The solution obtained was filtered using millipore filter of 0.22 μm size. The efficiency of the labeling, verified by ascending chromatography on Whatman No.1 paper was found to be 97.3 % (±1.6), while it was 96.8% (±2.3) using Whatman No.3 paper and 96.6% (± 2.1) using thin-layer chromatography. Chromatography by exclusion chromatography (Bio-Gel P 10) was used for confirmation of the above results. The labeled molecules were eluted first, followed by the molecules of Technetium-99m while the colloids remained attached to the column. The results of the present study are comparable with the results of previous studies reported in literature. (author)

  5. Technetium-99m Labelled Infection Imaging Agents. Chapter 7

    Infection specific radiopharmaceuticals can be used for diagnosis as well as for decision making in therapy and treatment follow-up. Most of the currently used tracers are not able to discriminate between infection and inflammation. Research has been going on to develop infection specific markers, and radiolabelled anti-infective agents look promising towards developing infection specific agents. Technetium-99m labelled antibiotics might also have the potential to differentiate sterile inflammation from infection. There are numerous ongoing studies reporting the use of other radiolabelled antibacterial and antifungal agents for detecting infection. Other promising agents are antimicrobial peptides as they preferentially bind to membranes of bacteria over mammalian cells and, therefore, will discriminate between infection and sterile inflammation. Clinical studies are now being undertaken with these agents and further evaluation with different types of pathogens such as viruses, fungi, parasites and intracellular pathogens in humans will provide new infection specific diagnostic agents. (author)

  6. Ventilation imaging with 99m technetium labeled aerosols

    The major clinical use of ventilation perfusion scintigraphy is for the diagnosis of pulmonary embolism (PE). Accurate diagnosis of PE is essential since effective treatment if available. The scintigraphic characteristic of PE are segmental perfusion defects in lung that is normally ventilated. The inherent shortcoming of perfusion scintigraphy is its lack of specificity. Combining a ventilation study with perfusion imaging improves the diagnostic specificity of lungs scintigraphy. This article describes clinical use of simple same day ventilation and perfusion imaging technique. The technique is based on a low dose ventilation procedure using 99m Tc labelled aerosol immediately followed by a standard dose perfusion procedure. (author)

  7. Labelling of Klebsiella pneumoniae with technetium-99m: a preliminary communication

    The labeling of Klebsiella pneumoniae with technetium-99m (Tc-99m) seems to depend on the stannous ion (Sn++) concentration. Starting at 3μg/ml of this ion is the suspension fluid an uptake of Tc-99m close to 90% was observed. The labeling is apparently strong, since the eluation of Tc-99m, after incubation of the tagged culture, in a water-bath at 370C for several hours, was very weak. The viability of the culture was unaltered after treatment with tin and Tc-99m. (Author)

  8. Placental localization in abdominal pregnancy using technetium-99m-labeled red blood cells

    In a patient with third trimester abdominal pregnancy with fetal demise, technetium-99m-labeled erythrocytes (99mTc-RBCs) localized the placenta preoperatively, after nonvisualization by ultrasonography and arteriography. Extrauterine placental localization by blood-pool imaging may be useful when ultrasound fails

  9. Technetium-99m Labelled Molecules for Hypoxia Imaging. Chapter 15

    In the field of diagnostic imaging, the concept of imaging hypoxia constitutes an important development and 99mTc labelled vectors have taken a long stride in this direction. Delineation of hypoxic cells amidst oxygenated cells has a strong bearing on treatment strategies and regimes, since hypoxic cells are normally resistant to therapy, thus having a direct influence on the extent of tumour propagation and malignant progression. Inherent drawbacks in the invasive methods currently available for measuring hypoxia led to the development of non-invasive modalities such as use of radiolabelled molecules for imaging hypoxia. In the chapter, an attempt is made to provide a comprehensive overview of 99mTc based radiopharmaceutical agents as well as a brief discussion of other radiolabelled agents that show considerable promise in diagnostic imaging of tumour hypoxia. The review also discusses the phenomenon of hypoxia, other non-invasive methods of detecting hypoxia currently available and the evolution of radiopharmaceuticals to image hypoxia. (author)

  10. Synthesis and characterisation of technetium-99m labelled ciprofloxacin (Infecton)

    Full text: Infecton is Tc-99m labelled Ciprofloxacin, which is a synthetic carboxyquinolone derivative with broad-spectrum antimicrobial activity. It is a new class of radiopharmaceutical designed for imaging live bacterial infection. Conventional imaging agents such as Tc-99m or In-111 labelled leucocytes are either time-consuming or hazardous due to blood handling. These can be obviated by the use of Infecton which we synthesised by modifying the procedure described by Britton and co-workers (Lancet 1996;..347: 233-235). Bioassay and animal studies have been performed with a view to its use in infection imaging in patients. The first task was to prepare pure ciprofloxacin from its commercially available lactate salt. This was achieved by isoelectric precipitation at pH 8.6 by adding sodium hydroxide to the formulation. The resultant precipitate was washed with 200 mL of water for injection and filtered through a cintered-glass filtering unit. The precipitate was free of lactate and sodium as analysed by Biochem analyser. The UV spectrophotometric analysis showed an absorption peak at 276.3 nm which is close to the theoretical value of 277 nm, thus confirming the purity of the compound. Infecton was synthesised by adding 2 mg of pure ciprofloxacin, 0.4 mg of formimidine sulfinic acid ( non-stannous reducing agent) and 1.0 GBq Tc-99m pertechnetate in a final volume of 1.0 mL saline into a sterile N2-filled Amersham vial and boiling the mixture at 100 deg C for 10 min. The purity of the product was 40-45%. It was passed through a DEAE Sephadex A-25 column and eluted with phosphate buffered saline (0.01M, pH 6.9) with a purity of >96%. The preparation was characterised by bioassay (n=3) by adding Infecton to four different broths of bacterial strains viz Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and MRSA with resultant binding of 50.4, 45.6, 48.5 and 50.3% respectively. The binding was less than 1.0% when either ciprofloxacin or

  11. Synthesis and characterisation of technetium-99m labelled ciprofloxacin (Infecton)

    Kumar, V.; Choong, K.K.L.; Olma, T.R.; Mieczkowski, S. [Westmead and the New Childrens Hospital, Westmead, NSW (Australia). Department of Nuclear Medicineand Ultrasound and Centre for infectious Diseases and Microbiology laboratory Services

    1998-06-01

    Full text: Infecton is Tc-99m labelled Ciprofloxacin, which is a synthetic carboxyquinolone derivative with broad-spectrum antimicrobial activity. It is a new class of radiopharmaceutical designed for imaging live bacterial infection. Conventional imaging agents such as Tc-99m or In-111 labelled leucocytes are either time-consuming or hazardous due to blood handling. These can be obviated by the use of Infecton which we synthesised by modifying the procedure described by Britton and co-workers (Lancet 1996;..347: 233-235). Bioassay and animal studies have been performed with a view to its use in infection imaging in patients. The first task was to prepare pure ciprofloxacin from its commercially available lactate salt. This was achieved by isoelectric precipitation at pH 8.6 by adding sodium hydroxide to the formulation. The resultant precipitate was washed with 200 mL of water for injection and filtered through a cintered-glass filtering unit. The precipitate was free of lactate and sodium as analysed by Biochem analyser. The UV spectrophotometric analysis showed an absorption peak at 276.3 nm which is close to the theoretical value of 277 nm, thus confirming the purity of the compound. Infecton was synthesised by adding 2 mg of pure ciprofloxacin, 0.4 mg of formimidine sulfinic acid ( non-stannous reducing agent) and 1.0 GBq Tc-99m pertechnetate in a final volume of 1.0 mL saline into a sterile N{sub 2}-filled Amersham vial and boiling the mixture at 100 deg C for 10 min. The purity of the product was 40-45%. It was passed through a DEAE Sephadex A-25 column and eluted with phosphate buffered saline (0.01M, pH 6.9) with a purity of >96%. The preparation was characterised by bioassay (n=3) by adding Infecton to four different broths of bacterial strains viz Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and MRSA with resultant binding of 50.4, 45.6, 48.5 and 50.3% respectively. The binding was less than 1.0% when either ciprofloxacin or

  12. Complexes of technetium-99m with tetrapeptides, a new class of 99mTc-labelled agents

    concluded that tetrapeptides are an interesting group of technetium complexing agents which can easily be labelled with 99mTc at room temperature in alkaline medium. This class offers the possibility of a wide variety of derivatives, just by substituting one or more amino acids. This group of ligands thus opens a new research field of 99mTc-complexes with potential usefulness in several areas

  13. Technetium-99m labeling anti-amastigote polyclonal antibodies of Leishmania amazonensis

    Anti-amastigote polyclonal antibody (IgG) was incubated with solutions of stannous chloride and sodium borohidride. After that, 3.7 MBq of technetium-99m (99mTc) was added. A labeling yield of the antibody about 84% was obtained. After filtration of 99mTc-IgG, the radiochemical purity increased from 84 to 95%. The labeling of IgG with 99mTc did not modify the immunoreactivity of the antibody, since it was able to identify in vitro and in vivo the specific antigen of Leishmania amazonensis

  14. Technetium-99m labeling anti-amastigote polyclonal antibodies of Leishmania amazonensis

    Araujo, J.G.V.C.; Toledo, V.P.C.P.; Guimaraes, T.M.P.D.; Bernardo-Filho, M.; Simal, C.J.R.; Mota, L.G.; Diniz, S.O.F.; Cardoso, V.N. E-mail: cardosov@farmacia.ufmg.br

    2002-05-01

    Anti-amastigote polyclonal antibody (IgG) was incubated with solutions of stannous chloride and sodium borohidride. After that, 3.7 MBq of technetium-99m ({sup 99m}Tc) was added. A labeling yield of the antibody about 84% was obtained. After filtration of {sup 99m}Tc-IgG, the radiochemical purity increased from 84 to 95%. The labeling of IgG with {sup 99m}Tc did not modify the immunoreactivity of the antibody, since it was able to identify in vitro and in vivo the specific antigen of Leishmania amazonensis.

  15. Gastrointestinal transit of technetium-99m-labeled cellulose fiber and indium-111-labeled plastic particles

    We introduce two new nondigestible solid markers for gastrointestinal transit measurements. One is technetium-99m-labeled cellulose fiber [99mTc]CF, the other is indium-111-labeled plastic particles [111In]PP of 2- to 3-mm diameter. In six healthy male volunteers gastric emptying and small intestinal transit of the two markers were obtained simultaneously. Large intestinal transit of [111In]PP was also obtained. Technetium-99m CF had acceptable stability properties in the proximal gastrointestinal segments. Indium-111 PP was almost completely stable in all segments. Mean gastric emptying time was 1.13 +/- 0.24 hr (mean +/- s.d.) for [99mTc]CF and 1.94 +/- 0.78 hr for [111In]PP. The difference was significant (p less than 0.05). Mean small intestinal transit time was 3.85 +/- 0.61 hr (mean +/- s.d.) for [99mTc]CF and 4.03 +/- 0.34 hr for [111In]PP. The difference was not significant (p less than 0.5). Mean large intestinal transit time of [111In]PP was 23 +/- 11 hr (mean +/- s.d.). We also suggest a simple deconvolution principle for the interpretation of the small intestinal and the large intestinal transit data

  16. Labelling of Schistosoma mansoni cercariae with 99 m technetium: a preliminary communication

    The labelling of Schistosoma mansoni cercariae with technetium 99 m (99 m Tc) is performed. The effect of stannous chloride concentration in the labelling process, the stability of the labelling and the viability of the 99 m Tc labeled cercariae are studied. The incorporation of the radioactivity in the cercariae increases with an increase in the stannous chloride concentration reaching constant values threshold 13000 u M. The characteristic motion of the cercariae was only modify at the concentration of 130000 u M. (M.A.C.)

  17. Preclinical evaluation of technetium 99m-labeled P1827DS for infection imaging and comparison with technetium 99m IL-8

    Krause, Sabine [Bayer Schering Pharma AG, Global Drug Discovery, D-13342 Berlin (Germany); Rennen, Huub J.; Boerman, Otto C. [Radboud University, Nijmegen Medical Centre, 6500 HB Nijmegen (Netherlands); Baumann, Sabine; Cyr, John E.; Manchanda, Rajesh; Lister-James, John [Bayer Schering Pharma AG, Global Drug Discovery, D-13342 Berlin (Germany); Corstens, Frans C. [Radboud University, Nijmegen Medical Centre, 6500 HB Nijmegen (Netherlands); Dinkelborg, Ludger M. [Bayer Schering Pharma AG, Global Drug Discovery, D-13342 Berlin (Germany)], E-mail: sabine.krause@bayerhealthcare.com

    2007-11-15

    Background: The technetium 99 m ({sup 99m}Tc)-radiolabeled, leukocyte-avid peptide-glycoseaminoglycan complex, [{sup 99m}Tc]P1827DS, has been synthesized as an improved infection/inflammation imaging agent to [{sup 99m}Tc]P483H (LeukoTect, Diatide). In a phase I/II clinical trail, [{sup 99m}Tc]P483H images were equivalent to those obtained with {sup 111}In ex vivo labeled leukocytes. However, there was physiologic accumulation of radioactivity in the body that could hamper interpretation of the images. In this study, the potential of [{sup 99m}Tc]P1827DS for infection imaging was assessed in comparison with [{sup 99m}Tc]P483H and the well-described imaging agent [{sup 99m}Tc] hydrazinonicotinamide (HYNIC)-interleukin 8 (IL-8). Methods: The binding of [{sup 99m}Tc]P1827DS to human blood cell was studied in vitro. A rabbit Escherichia coli infection model was used to perform the biodistribution and imaging studies with [{sup 99m}Tc]P1827DS, [{sup 99m}Tc]P483H and [{sup 99m}Tc]HYNIC-IL-8. Results: [{sup 99m}Tc]P1827DS binds to leukocytes but not to erythrocytes. The leukocyte binding was not saturable up to an investigated concentration of 10 {mu}M. The accumulation of [{sup 99m}Tc]P1827/DS at the infection site strongly depends on the P1827/DS ratio and was optimal at a molar ratio of 10:1. [{sup 99m}Tc]P1827DS shows improved biodistribution over [{sup 99m}Tc]P483H with similar uptake at the infection site. Abscess uptake of [{sup 99m}Tc]HYNIC-IL-8 was approximately three times higher than that of [{sup 99m}Tc]P1827DS. [{sup 99m}Tc]HYNIC-IL-8 showed high accumulation in the kidneys, whereas [{sup 99m}Tc]P1827DS showed high lung uptake and slightly higher accumulation in the liver and spleen. Conclusion: [{sup 99m}Tc]P1827DS is a potential new inflammation imaging agent, which clearly visualized the abscess in the rabbit E. coli infection model and showed improved biodistribution compared to [{sup 99m}Tc]P483H. However, the infection uptake and biodistribution of

  18. Evaluation of five miniature chromatography systems for determining labeling efficiency of technetium Tc 99m pentetate.

    Robbins, P J

    1983-04-01

    The reliability and reproducibility of five miniature chromatography systems for the radiochemical purity of 99mTc-labeled technetium Tc 99m pentetate was evaluated. Radiochemical purity of technetium Tc 99m pentetate was determined 15-30 minutes after preparation once a month for nine consecutive months. A reference value was determined by gel filtration or by conventional-length paper chromatography and thin-layer chromatography. Radiochemical purity was determined simultaneously by five miniature chromatography systems. The miniature systems included an in-house system and commercial systems distributed by Ackerman Nuclear, Ashley Innovations, Atomic Products, and Technical Advancement. Each miniature system was tested in duplicate. A follow-up comparison of the Ackerman Nuclear and in-house systems was performed for an additional nine months. Labeling efficiency by the reference method was greater than 97% for all nine months. The miniature systems gave results that were comparable in most months. Very low labeling efficiency occurred with the Ackerman Nuclear system in month 9. The follow-up comparison produced only one unconfirmed result for the Ackerman Nuclear system that would have caused a laboratory to erroneously discard a batch of technetium Tc 99m pentetate. The miniature chromatography systems evaluated generally will give reliable and reproducible results for the radiochemical purity of technetium Tc 99m pentetate for nine months after receipt of the systems. PMID:6342380

  19. Evaluation of five miniature chromatography systems for determining labeling efficiency of technetium Tc 99m pentetate

    The reliability and reproducibility of five miniature chromatography systems for the radiochemical purity of 99mTc-labeled technetium Tc 99m pentetate was evaluated. Radiochemical purity of technetium Tc 99m pentetate was determined 15-30 minutes after preparation once a month for nine consecutive months. A reference value was determined by gel filtration or by conventional-length paper chromatography and thin-layer chromatography. Radiochemical purity was determined simultaneously by five miniature chromatography systems. The miniature systems included an in-house system and commercial systems distributed by Ackerman Nuclear, Ashley Innovations, Atomic Products, and Technical Advancement. Each miniature system was tested in duplicate. A follow-up comparison of the Ackerman Nuclear and in-house systems was performed for an additional nine months. Labeling efficiency by the reference method was greater than 97% for all nine months. The miniature systems gave results that were comparable in most months. Very low labeling efficiency occurred with the Ackerman Nuclear system in month 9. The follow-up comparison produced only one unconfirmed result for the Ackerman Nuclear system that would have caused a laboratory to erroneously discard a batch of technetium Tc 99m pentetate. The miniature chromatography systems evaluated generally will give reliable and reproducible results for the radiochemical purity of technetium Tc 99m pentetate for nine months after receipt of the systems

  20. Tin colloid labelled with technetium-99m as a diagnostic agent

    The invention relates to a process for preparing a tin colloid labelled with technetium 99m, whereby technetium 99m as an aqueous solution of the pertechnetate ion TcO4- is added to a reagent comprising one part by weight of sodium, potassium or ammonium fluoride and from 0.00075 to 0.75 part by weight of stannous tin. This reagent can be in an aqueous solution but it is preferably used in the solid freeze-dried state. The pertechnetate solution can be a solution in water or in a normal saline solution and it can be easily obtained by elution of technetium 99m generator. If the eluate is sterile, it is desirable that the reagent to which this solution is added should likewise be sterile

  1. Technetium-99m-labeled recombinant tissue plasminogen activator for the imaging of emboli in vivo

    Takahashi, Akihiro; Itoh, Kazuo; Tsukamoto, Eriko; Furudate, Masayori; Kamiyama, Hiroyasu; Abe, Hiroshi (Hokkaido Univ., Sapporo (Japan). School of Medicine)

    1993-07-01

    Tissue-type plasminogen activator (t-PA) effectively lyses activate thrombus by direct action. Recombinant t-PA (rt-PA) was labeled with technetium-99m ([sup 99m]Tc) to investigate the in vivo binding to fibrin clots in a feline cerebral embolism model created by insertion of an artificial fibrin clot within the carotid artery. [sup 99m]Tc-rt-PA administered intravenously provided clearer imaging of clots after priming with cold rt-PA, with uptake peaking 5-10 minutes after the injection. [sup 99m]Tc-labeled human serum albumin was not retained at clot sites. Systemically administered [sup 99m]Tc-rt-PA binds to fibrin clots within carotid arteries in our feline model. Our results suggest that the interaction of intrinsic plasminogen activator inhibitors with extrinsically administered rt-PA may regulate the demonstration of a clot, although the precise mechanism is unclear. (author).

  2. Labelling of CTMP with technetium-99m as radiopharmaceutical for bone cancer seeking

    Radiopharmaceutical for bone cancer seeking was developed in variable compound labelled with technetium-99m, formally pyrophosphate compound and diphosphonate compound such as methylenediphosphonate (99mTc-MDP), hydroxyethylene diphosphonate (99mTc-HEDP) and hydroxy methylene diphosphonate (99mTc-HMDP). Either pyrophosphate or diphosphonate still unsatisfied to use as radiopharmaceutical for bone cancer seeking because the high accumulation in lever, muscle and blood. The compound of tetraaminotetraphosphonate groups have the higher affinity in bone because of four phosphonate and four amine groups. This experiment was done to label the compound group especially 1,4,8, 1-tetraazacyclotetradecyl-1,4,8,11-tetramethylene phosphonic acid (CTMP) with technetium-99m radionuclide. To obtain the maximal labelling result, some parameters such as pH, amount of SnCl2 reductor and ligan, time and temperature of reaction are optimized. The optimal condition obtained were pH of 4-6, 100 µg of SnCl2 reductor, 500 µg of CTMP ligand and labelling time of 10 minutes in boiling water or 30 minutes in room temperature, with labelling efficiency was >95 %. (author)

  3. 99m-technetium labelling of a tumor associated murine monoclonal antibody for immunoscintigraphic studies in man

    The present study refers to the preparation of a 99m-Technetium labelled murine monoclonal antibody for clinical application. The monoclonal antibody was incubated with a 20fold molar excess of 2-iminothiolane. The free thiol groups created, were capable of binding reduced technetium. Labelling took place through an exchange reaction with 99m-Technetium-Glucoheptonate. The labelling conditions were studied extensively. (Author)

  4. Improved method to label beta-2 agonists in metered-dose inhalers with technetium-99m

    Ballinger, J.R.; Calcutt, L.E.; Hodder, R.V.; Proulx, A.; Gulenchyn, K.Y. (Ottawa Civic Hospital, Ottawa (Canada). Div. of Nuclear Medicine and Respiratory Unit)

    1993-01-01

    Labelling beta-2 agonists in a metered-dose inhaler (MDI) with technetium-99m allows imaging of the deposition of the aerosol in the respiratory tract. We have developed an improved labeling method in which anhydrous pertechnetate is dissolved in a small volume of ethanol, diluted with a fluorocarbon, and introduced into a commercial MDI. Imaging the MDI demonstrated that the [sup 99m]Tc was associated with the active ingredient, not just the propellant. The method has been used successfully with salbutamol and fenoterol MDIs and should be directly applicable to other MDIs which contain hydrophilic drugs. (Author).

  5. IL-2 labeled with 99mTechnetium by an indirect method

    IL-2 and the other cytokines labeled with 99mTc are an interesting option to early diagnosis of autoimmune diseases and monitoring with nuclear medicine images. The aim of this study was to obtain by indirect method IL-2 labeled with 99mTechnetium using Benzoyl MAG3 chelating agent, for in vivo diagnosis of lymphocytic infiltration. IL-2 is a small, relatively fragile protein, and it is essential to retain its receptor binding capacity after labeling. Two different methods of labeling have been proven: Pre-conjugation labeling method: we used NHS- Hynic as a chelator agent and labeled this conjugated protein with 99mTc using tricine as coligand. Albumin was used as a model for the conjugation and labeling steps. The albumin was labeled by this method with a good labeling efficiency but the IL-2 protein could not be labeled with this approach. Post- conjugation labeling method: we used the bifunctional chelating agent, benzoyl MAG3, this ligand is first labeled with 99mTc and then is conjugated to the protein. The N3S Logan complex was incubated for 30 minutes and then measured by RP- HPLC. An active ester of the labeled Logan was formed and was incubated with Il-2 at room temperature and basic pH to promote the conjugation between the active ester and the protein. The labeling efficiency was determined by RP-HPLC using a C 18 column. The albumin protein was also labeled by this method and the radiochemical purity was measured by RP- HPLC using a GPC column and the labeling efficiency was 80%. The next objectives are to explore different strategies for purifying the 99mTc-IL-2 and to evaluate the capacity of IL-2 to bind to its receptor after labeling. (author)

  6. Preparation, characterization, and biodistribution study of technetium-99m labelled crotalus venom

    Technetium-99m (99mTc) is a radionuclide widely used for nuclear medical examination. Called the workhorse of nuclear medicine, 99mTc is the favoured choice because it has the appropriate physical and chemical characteristics for imaging. The gamma radiation emitted by 99mTc has the appropriate energy (140 keV) to provide high efficiency detection with the advantage of reduced radiation burden for the patient and environmental (half-life of 6 h). Crotalus venom (CV) has been tested in a very few human cases and it has been shown to reduce tumours. Our group has shown that CV has antitumoural effects against some brain tumours in vitro. Pharmacokinetics and tissue distribution studies are very important for clinical use. The aim of the present study was to obtain an analogue of CV labelled with 99mTc which preserves its biological activity for use in biodistribution and binding studies. A direct method for 99mTc-labelling venom has been evaluated according to Pauwels, et al. The method employs stannous chloride and sodium borohydride as reducing agents. By altering the reaction conditions high yield of labelled venom was achieved. Labeling yield was estimated using chromatographic systems. Biological activity was assessed by haemolytic activity study. Comparing haemolytic activities of labelled and unlabeled venom we observed that neither 99mTc-CV nor CV caused direct lysis on washed erythrocytes. However, both of them caused indirect hemolysis provided that the incubation medium contained an exogenous source of lecithin. So, the biological activity of CV was preserved after labeling. Biodistribution of 99mTc-CV was evaluated in mice. Male swiss mice were injected i.p. with 99mTc-CV, vital organs were isolated and their respective radioactivities were measured. High radioactivity was found in the kidneys suggesting renal excretion. On the other hand, this radioactivity was displaced in animals pre-treated with excess of non labelled CV (not shown). These data show

  7. Guava extract (Psidium guajava) alters the labelling of blood constituents with technetium-99m

    ABREU P.R.C.; ALMEIDA M.C.; BERNARDO R.M.; BERNARDO L.C.; BRITO L.C.; GARCIA E.A.C.; FONSECA A.S.; BERNARDO-FILHO M.

    2006-01-01

    Psidium guajava (guava) leaf is a phytotherapic used in folk medicine to treat gastrointestinal and respiratory disturbances and is used as anti-inflammatory medicine. In nuclear medicine, blood constituents (BC) are labelled with technetium-99m (99mTc) and used to image procedures. However, data have demonstrated that synthetic or natural drugs could modify the labelling of BC with 99mTc. The aim of this work was to evaluate the effects of aqueous extract of guava leaves on the labelling of BC with 99mTc. Blood samples of Wistar rats were incubated with different concentrations of guava extract and labelled with 99mTc after the percentage of incorporated radioactivity (%ATI) in BC was determined. The results suggest that aqueous guava extract could present antioxidant action and/or alters the membrane structures involved in ion transport into cells, thus decreasing the radiolabelling of BC with 99mTc. The data showed significant (P<0.05) alteration of ATI in BC from blood incubated with guava extract.

  8. Scintigraphic evaluation of chronic osteomyelitis with technetium 99 m labeled polyclonal immunoglobulin

    Active chronic osteomyelitis or complicating osteomyelitis are difficult to be diagnosed by radiological imaging modalities, such as plain radiograph and CT. They frequently cause increased bone remodeling, leading to nonspecific uptake of Tc 99 m-bone scan agents and gallium-67. New radiopharmaceuticals with greater infection avidity are being developed, including the nonspecific polyclonal immunoglobulin (IgG) labeled with technetium 99 m. Tc 99 m-IgG may be available as a ready to use kit, with no reported side effects, low patient absorbed radiation dose and low cost. Material and Methods: 23 bone segments with suspected active chronic osteomyelitis or violated bone osteomyelitis were studied by Tc 99 m IgG scintigraphy. All patients underwent standard three phase bone scintigraphy using methylene diphosphonate (Tc 99 m MDP), gallium 67 scintigraphy and plain radiographs, compared with clinical evaluation and laboratory tests values. Results: Infection was found in 8 sites. Sensitivity and specificity for Tc-99 m MDP, gallium 67 and Tc 99 m IgG scintigraphy were, respectively, 88 and 36%, 75 and 73%, 88 and 82%. Conclusion: Tc-99 m IgG may be useful in the scintigraphic evaluation of osteomyelitis. (author)

  9. Labeling of Temafloxacin with Technetium-99m Eluted from Zirconium Molybdate-99Mo Column Matrix

    A 99Mo/99mmTc radioisotope generator was prepared by loading zirconium molybdate column matrix with the carrier-free Mo radio nuclide. Greater than 83.2±0.7% of the generated 99mTc was immediately and reproducibly eluted by passing 10 ml 0.9% Na CI solution through the column matrix at a flow rate 0.5 ml/min with high chemical, radionuclidic( 99mTc) and radiochemical purity (≤ 97.7% as 99mTcO4. Labeling of temafloxacin with technetium-99m using stannous chloride as a reducing agent was investigated. The optimum condition that gives high labeling yield of mTc-temafloxacin complex, 98.9%, was achieved using 5 mg temafloxacin, 100 μg Sn (II), at ph 7 and 10 min reaction time. For in vivo binding of 99mTc-temafloxacin pharmacokinetic studies were carried in experimentally induced infection, in the left thigh, using Staphylococcus aureus in rats. Both thighs of the rats were dissected and counted and the ratio of bacterial infected thigh/contralateral thigh was then evaluated. The time for maximum accumulation of 99mTc-temafloxacin at the site of infection (T/NT = 6.5 ± 0.7) was 30 min post intravenous injection, followed by gradual decline. So, 99m Tc-temafloxacin complex is a simple and stable preparation suitable for infection imaging after 30 min post injection

  10. Development new radiopharmaceutical based on 5-thio-d- glucose labeled technetium-99m

    Stasyuk, E. S.; Skuridin, V. S.; Ilina, E. A.; Rogov, A. S.; Nesterov, E. A.; Sadkin, V. L.; Larionova, L. A.; Varlamova, N. V.; Zelchan, R.

    2016-06-01

    The article considers the obtaining and possibility of using 5-thio-D-glucose labeled technetium-99m for the diagnosis of malignant tumors by single photon emission computed tomography. The analysis of the level of international developments of radiopharmaceuticals based on derivatives of glucose has been carried out. Also the article provides information on of using experimental batches of lyophilisate on the basis of 5-thio-D-glucose for preliminary biomedical testing on the mice.

  11. Contribution of technetium 99m-labelled pyrophosphate bone scintigraphy in infectious spondylodiscitis

    This work examines the contribution of technetium 99m(sup(99m)Tc)-labelled pyrophosphate bone scintigraphy in infectious spondylodiscitis and attempts to define its importance in the diagnosis of lesions and their subsequent supervision in patients under treatment. 5 to 15 millicuries of sup(99m)Tc-labelled pyrophosphates are injected intraveinously. Bone uptake is strong and durable; 1.3% of the injected activity is found in the blood by the fifth hour. The skeleton may be explored: - either one segment at a tome with a scintillation camera, - or all at once and more quickly with a whole-body device taking front and black exposures. Bone scintigraphy appears as a basic technique in the study of infectious spondylodiscitis. Moreover the use of increasingly efficient equipment, the quantification of results and perhaps the development of new tracers augur well for a technique which is already acknowledged to be of fundamental interest

  12. Technetium-99m labelled antimicrobial peptides discriminate between bacterial infections and sterile inflammations

    The aim of this study was to select technetium-99m labelled peptides that can discriminate between bacterial infections and sterile inflammations. For this purpose, we first assessed the binding of various 99mTc-labelled natural or synthetic peptides, which are based on the sequence of the human antimicrobial peptide ubiquicidin (UBI) or human lactoferrin (hLF), to bacteria and to leucocytes in vitro. In order to select peptides that preferentially bind to bacteria over host cells, radiolabelled peptides were injected into mice intraperitoneally infected with Klebsiella pneumoniae (K. pneumoniae) and the amount of radioactivity associated with the bacteria and with the leucocytes was quantitated. The next phase focussed on discrimination between bacterial infections and sterile inflammatory processes using 99mTc-labelled peptides in mice intramuscularly infected with various bacteria (e.g. multi-drug-resistant Staphylococcus aureus) and in animals that had been injected with lipopolysaccharides (LPS) of bacterial origin to create a sterile inflammatory process. Also, we studied the distribution of 99mTc-labelled UBI 29-41 and UBI 18-35 in rabbits having an experimental thigh muscle infection with K. pneumoniae and in rabbits injected with LPS. Based on the results of our in vitro and in vivo binding assays, two peptides, i.e. UBI 29-41 and UBI 18-35, were selected as possible candidates for infection imaging. The radiolabelled peptides can detect infections with both gram-positive and gram-negative bacteria in mice as early as 5-30 min after injection, with a target-to-non-target (T/NT) ratio between 2 and 3; maximum T/NT ratios were seen within 1 h after injection. In rabbits, high T/NT ratios (>5) for 99mTc-labelled UBI 29-41 were observed from 1 h after injection. No accumulation of the selected 99mTc-labelled UBI-derived peptides was observed in thighs of mice and rabbits previously injected with LPS. Scintigraphic investigation into the biodistribution of 99mTc-labelled

  13. Direct labeling of isoniazid with technetium-99m for diagnosis of tuberculosis

    Isonicotinic acid hydrazide (isoniazid) is one of the most effective agents in tuberculosis therapy. Hence it was chosen as ligand for 99mTc labeling and imaging in the developed animal model with a gamma camera. Direct labeling of isoniazid with technetium-99m was studied. Factors affecting the radiolabeling efficiency such as amount of reducing agent, pH and time of the reaction were studied. Biodistribution of the labeled compound was performed in Sprague-Dawley rats. The localization kinetics of the radiolabeled complex was also studied in the developed animal model by injecting 100-125 MBq 99mTc-isoniazid intravenously in the ear of rabbit and the images were taken with a gamma camera. Optimum conditions gave > 98% labeling efficiency of 99mTc-isoniazid. Biodistribution studies in rats revealed that the maximum uptake was in kidneys (15%, 8% and 2.5% at 0.5, 4 and 24 hours, respectively), indicating renal excretion of the 99mTc-isoniazid. High accumulation was obtained in liver (10%, 11% and 4% at 0.5, 4 and 24 hours, respectively) and significant radioactivity was also seen in the intestines (8%, 6% and 1% at 0.5, 4 and 24 hours, respectively), indicating hepatobiliary excretion of the complex. Less than 2% uptake in stomach until 24 hours confirmed good in vivo stability of the complex. 99mTc-isoniazid initially accumulated in infective lesions of S. aureus in rabbits due to hyper-vascularity, but because of its non specificity for S. aureus the residency of 99mTc-isoniazid was low and it showed rapid wash out from the lesion, whereas residency of tubercular lesion was high and it remained in the tubercular lesion in the delayed images also. The results suggest that 99mTc-isoniazid is a specific agent for localization of tubercular lesions. (orig.)

  14. Direct labeling of isoniazid with technetium-99m for diagnosis of tuberculosis

    Roohi, S.; Mushtaq, A.; Jehangir, M. [Isotope Production Div., Pakistan Inst. of Nuclear Science and Technology, P.O. Nilore, Islamabad (Pakistan); Malik, S.A. [Dept. of Biological Sciences, Quaid-e-Azam Univ., Islamabad (Pakistan)

    2006-07-01

    Isonicotinic acid hydrazide (isoniazid) is one of the most effective agents in tuberculosis therapy. Hence it was chosen as ligand for {sup 99m}Tc labeling and imaging in the developed animal model with a gamma camera. Direct labeling of isoniazid with technetium-99m was studied. Factors affecting the radiolabeling efficiency such as amount of reducing agent, pH and time of the reaction were studied. Biodistribution of the labeled compound was performed in Sprague-Dawley rats. The localization kinetics of the radiolabeled complex was also studied in the developed animal model by injecting 100-125 MBq {sup 99m}Tc-isoniazid intravenously in the ear of rabbit and the images were taken with a gamma camera. Optimum conditions gave > 98% labeling efficiency of {sup 99m}Tc-isoniazid. Biodistribution studies in rats revealed that the maximum uptake was in kidneys (15%, 8% and 2.5% at 0.5, 4 and 24 hours, respectively), indicating renal excretion of the {sup 99m}Tc-isoniazid. High accumulation was obtained in liver (10%, 11% and 4% at 0.5, 4 and 24 hours, respectively) and significant radioactivity was also seen in the intestines (8%, 6% and 1% at 0.5, 4 and 24 hours, respectively), indicating hepatobiliary excretion of the complex. Less than 2% uptake in stomach until 24 hours confirmed good in vivo stability of the complex. {sup 99m}Tc-isoniazid initially accumulated in infective lesions of S. aureus in rabbits due to hyper-vascularity, but because of its non specificity for S. aureus the residency of {sup 99m}Tc-isoniazid was low and it showed rapid wash out from the lesion, whereas residency of tubercular lesion was high and it remained in the tubercular lesion in the delayed images also. The results suggest that {sup 99m}Tc-isoniazid is a specific agent for localization of tubercular lesions. (orig.)

  15. The effect of drugs on the labeling of blood elements with technetium-99m.

    Braga, A C; Oliveira, M B; Feliciano, G D; Reiniger, I W; Oliveira, J F; Silva, C R; Bernardo-Filho, M

    2000-07-01

    The influence of drugs on the labeling of red blood cells and plasma proteins with 99mTc has been reported. Any drug, which alters the labeling of the tracer, could be expected to modify the disposition of the radiopharmaceuticals. Red blood cells (RBC) labeled with technetium-99m (99mTc) are used for several evaluations in nuclear medicine. We have evaluated the effect of Thuya occidentalis, Peumus boldus and Nicotiana tabacum (tobacco) extracts on the labeling of RBC and plasma and cellular proteins with 99mTc. Blood was incubated with the drugs. Stannous chloride (SnCl2) solutions and 99mTc were added. Plasma (P) and blood cells (BC) were separated. The percentage of radioactivity (%ATI) bound to P and BC was determined. The %ATI on the plasma and cellular proteins was also evaluated by precipitation of P and BC samples with trichloroacetic acid (TCA) and isolation of soluble (SF) and insoluble (IF) fractions. The analysis of the results shows that there is a decrease in %ATI (from 97.64 to 75.89 percent) in BC with Thuya occidentalis extract. The labeling of RBC and plasma proteins can be decreased in presence of tobacco. This can be due either a direct or indirect effect (reactive oxygen species) of tobacco. The analysis of radioactivity in samples of P and BC isolated from samples of whole blood treated with Peumus boldus showed a rapid uptake of the radioactivity by blood cells in the presence of the Peumus boldus, whereas there was a slight decrease in the amount of 99mTc radioactivity in the TCA-insoluble fraction of plasma. This study shows that extracts of some medicinal plants can affect the radiolabeling of red blood cells with 99mTc using an in vitro technique. PMID:10903389

  16. Comparison of chromatography systems for radiochemical purity determination of lyophilized reagents labeled with technetium-99m

    Monteiro, Elisiane G.; Almeida, Erika V.; Ramos, Marcelo P.S.; Alves, Edson V.; Benedetti, Stella; Mengatti, Jair; Fukumori, Neuza T.O.; Matsuda, Margareth M.N., E-mail: elisianegodoy@terra.com.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    A variety of lyophilized reagents (LR) labeled with {sup 99m}Tc has been developed for determining organ function or assessing disease status by imaging methods. Usually, the quality of the radiopharmaceutical preparations is evaluated by paper chromatography (PC), thin layer chromatography (TLC), instant thin layer chromatography silica gel (ITLC-SG), high performance liquid chromatography (HPLC) on reverse-phase columns and capillary electrophoresis (CE). PC and TLC have been applied due to the low cost and short time in the determination of pertechnetate ({sup 99m}TcO{sub 4}-) and technetium dioxide ({sup 99m}TcO{sub 2}). The present study reports the comparison between PC and TLC chromatographic methods for determination of the radiochemical purity of LR labeled with {sup 99m}Tc from IPEN-CNEN/SP (Brazil). PC was performed with Whatman 3MM/1MM paper chromatography strips and TLC with ITLC-SG sheets or reversed phase (RP). RP was used only for ECD. Although the radioactivity profile of the separation of the species on both stationary phases was satisfactory, the difference in results for % {sup 99m}TcO{sub 4}- and {sup 99m}TcO{sub 2} was up to 4.2 % using PC for ECD and PYP. ITLC supports gave better resolution than conventional PC supports for these products. In ECD analysis, the comparison was performed between RP and ITLC-SG stationary phases for determination of {sup 99m}TcO{sub 4}-, {sup 99m}TcO{sub 2} and other impurities. It was observed that the sheet length as described in the United States Pharmacopoeia was not sufficient for a good separation of the product and the impurities. The results showed that there were not significant differences between PC and TLC chromatographic stationary phases are going to be accomplished. (author)

  17. Comparison of chromatography systems for radiochemical purity determination of lyophilized reagents labeled with technetium-99m

    A variety of lyophilized reagents (LR) labeled with 99mTc has been developed for determining organ function or assessing disease status by imaging methods. Usually, the quality of the radiopharmaceutical preparations is evaluated by paper chromatography (PC), thin layer chromatography (TLC), instant thin layer chromatography silica gel (ITLC-SG), high performance liquid chromatography (HPLC) on reverse-phase columns and capillary electrophoresis (CE). PC and TLC have been applied due to the low cost and short time in the determination of pertechnetate (99mTcO4-) and technetium dioxide (99mTcO2). The present study reports the comparison between PC and TLC chromatographic methods for determination of the radiochemical purity of LR labeled with 99mTc from IPEN-CNEN/SP (Brazil). PC was performed with Whatman 3MM/1MM paper chromatography strips and TLC with ITLC-SG sheets or reversed phase (RP). RP was used only for ECD. Although the radioactivity profile of the separation of the species on both stationary phases was satisfactory, the difference in results for % 99mTcO4- and 99mTcO2 was up to 4.2 % using PC for ECD and PYP. ITLC supports gave better resolution than conventional PC supports for these products. In ECD analysis, the comparison was performed between RP and ITLC-SG stationary phases for determination of 99mTcO4-, 99mTcO2 and other impurities. It was observed that the sheet length as described in the United States Pharmacopoeia was not sufficient for a good separation of the product and the impurities. The results showed that there were not significant differences between PC and TLC chromatographic stationary phases are going to be accomplished. (author)

  18. Technetium-99m labeling and fibronectin binding ability of Corynebacterium diphtheriae

    The use of radionuclides has permitted advances in areas of clinical and scientific knowledge. Several molecules and cells have been labelled with Technetium-99m (99mTc). The stannous chloride (SnCl2) has a significant influence on the labeling and stability of 99mTc radiotracers. The frequent risk of diphtheria epidemics has intensified interest in the virulence factors of Corynebacterium diphtheriae. Although studies have looked at potential adhesins including haemagglutinins and exposed sugar residues, the molecular basis of mechanisms of adherence remains unclear. Adherence of pathogens to mammalian tissues may be mediated by fibronectin (FN) found in body fluids, matrix of connective tissues, and cell surfaces. In the present study we evaluated the binding ability to human plasma FN by 99mTc labeled-C.diphtheriae. Due to adverse effects of stannous ions, microorganisms were submitted to survival and filamentation induction assays. Data showed a dose dependent susceptibility to SnCl2 bactericidal effects. Cell filamentation was observed for concentrations of SnCl2 > 110 μg/ml. Adherence levels of 99mTc labelled 241strain to coverslips coated with 20 μg/ml FN were higher (P = 0.0037) than coated with bovine serum albumin. FN binding by the sucrose fermenting 241 C. diphtheriae strain (8.9% + 2.6) was significantly lower (P=0.0139) than Staphylococcus aureus Cowan I strain (34.1% ± 1.2). Therefore, bacterial 99mTc labeling represents an additional tool that may contribute to the comprehension of C. diphtheriae interactions with host receptors such as FN that act as biological organizers by holding bacterial cells in position and guiding their migration. (author)

  19. Technetium-99m-diethyl-Ida instant kits:labelling kinetics and biological properties

    Numerous Tc-99m labelled radiopharmaceuticals have been developed as heptobiliary agents. Among those widely used clinically are Tc-99m N(2,6-dimethyl phenyl carbamoyl methyl) iminodiacetic acid (Tc-HIDA), Tc-99m N(2,6-diethylphenyl carbamoyl methyl) iminodiacetic acid (Tc-diethyl IDA) and Tc-99m N(2,6-diisopropyl IDA). The higher hepatoextraction efficiency and shorter hepatobiliary transit time of Tc-diethyl IDA make it superior for hepatobiliary scintigraphy in the clinical setting. However, Tc-diethyl IDA has been the best tracer available especially in diorders of gallbladder. A formulation of stannous diethyl-IDA freeze dried powder, containing 50 gm of the ligand and 0.4 mg of SnCl2-2H2O, to be labelled with technetium has been developed for hepatobiliary scintigraphy. The optimal pH value of the final preparation was determination to be between 5.5-6.0. The freeze-dried kit is stable for 4 months and the instant Tc-99m diethyl IDA is stable for 5 hours

  20. Measurement of lymphatic function with technetium-99m-labelled polyclonal immunoglobulin

    A reliable method for measuring lymph flow in physiological units would be valuable, especially in conditions in which it is uncertain whether lymph flow is increased or decreased. The requirements of a radiopharmaceutical for such measurement include stable radionuclide labelling and rapid access to lymphatic vessels following tissue injection but no access to blood vessels. A soluble macromolecule is likely to come closest to meeting these requirements. Technetium-99m- labelled human polyclonal immunoglobulin (HIG) was therefore investigated firstly in comparison with 99mTc-labelled human serum albumin (HSA) in patients undergoing routine lymphoscintigraphy and secondly with respect to injection site in a group of volunteers with post-mastectomy oedema (PMO). Subcutaneous injection of 99mTc-HIG into the web space of a distal extremity gave images in which lymphatic vessels were more clearly defined compared with images obtained after injection of 99mTc-HSA. Lymph nodes were also more clearly defined, suggesting specific retention of HIG, possibly through Fc-mediated binding. Peripheral blood sampling showed a delayed arrival in blood of radioactivity after 99mTc-HIG compared with 99mTc-HSA, although ultimately, the blood recovery of 99mTc-HIG was significantly higher (P 99mTc-HSA. Clearance rates of radioactivity from the injection site were not sinificantly different, however, between the two agents. In patients with PMO, web space injection of 99mTc-HIG gave excellent images of normal lymphatic vessels, of lymph nodes and of abnormal lymph drainage such as dermal backflow in swollen arms. In contrast, neither lymphatic vessels nor lymph nodes were visualised after injection into the skin of the dorsum of the distal forearm. Although there was no difference in clearance rates from the injection sites between normal and swollen arms with either agent in PMO, clearance was significantly faster following injection into the web space (0.11% per minute for normal and

  1. LeukoScan, sulesomab - kit for the preparation of technetium-99m labelled leukoscan

    LeukoScan, produce and commercialised by the Australian Radioisotope at ANSTO, is a radiodiagnostic agent consisting of a murine monoclonal antibody Fab' fragment, sulesomab, formulated to be labelled with technetium-99m. The active component, sulesomab, is a Fab' fragment generated from IMMU-MN3, a murine IgG1 monoclonal antibody produced in murine ascites IMMU-MN3 is purified from the ascitic fluid and is digested with pepsin to produce F(ab')2 fragments and subsequently reduced to produce the 50,000-dalton sulesomab. Each vial contains the non-radioactive materials necessary to prepare one patient dose LeukoScan is a sterile, lyophilized formulation, containing 0.31 mg of sulesomab per vial and includes 0.22 mg stannous chloride dihydrate, 3.2 mg potassium sodium tartrate tetrahydrate, 7.4 mg sodium acetate trihydrate, 5.5 mg sodium chloride, glacial acetic acid (trace), hydrochloric acid (trace), 37.8 mg sucrose, nitrogen (vacuum). The imaging agent, technetium-99m LeukoScan [technetium-99m sulesomab] is formed by reconstitution of the contents of the LeukoScan vial with 0.5 mL sodium chloride for injection USP followed by the addition of 1100 MBq of sodium pertechnetate [99mTc] in 1 mL of Sodium Chloride for Injection, USP. The resulting solution has a pH of 4.5-5.5 and is intended for intravenous use only. Following administration, the labelled antibody can be visualized by common nuclear medicine instrumentation. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  2. Lymphoma imaging with a new technetium-99m labelled antibody, LL2

    Murthy, S.; Sharkey, R.M.; Goldenberg, D.M.; Lee, R.E.; Pinsky, C.M.; Hansen, H.J.; Burger, K.; Swayne, L.C. (Center for Molecular Medicine and Immunology, Newark, NJ (United States) Garden State Cancer Center, Newark, NJ (United States) Immunomedics, Inc., Warren, NJ (United States) University Hospital, UMDNJ, Newark, NJ (United States). Dept. of Radiology Morristown Memorial Hospital, NJ (United States))

    1992-06-01

    The lesion detection capability of a new technetium-99m labelled B-cell lymphoma monoclonal antibody (MoAb) imaging agent, LL2, was evaluated in 8 patients with non-Hodgkin's lymphoma and 1 patient with chronic lymphocytic leukaemia. The MoAb kit consists of a 1-vial, 1-mg Fab' form of LL2 ready for instant labelling with technetium. The patients were injected with {proportional to}925 MBq (25 mCi) of {sup 99m}Tc-LL2 Fab' (1 mg), and planar and single photon emission tomography (SPET) studies were performed at 3-4 h post injection and at 24 h. There was no evidence of thyroid or stomach activity up to 24 h. Uniform splenic uptake was seen in all patients. Two non-lymphoma patients were also administered with the same agent and demonstrated a similar splenic distribution; therefore, splenic targeting was not scored as tumour-specific. A total of 29 from 48 tumour sites were detected by scintigraphy, including tumours of various grades and histological types. Excluding 1 patient who had a large tumour burden of over 500 g, 29 of 33 lesions were detected. One patient was free of disease at the time of the study and had a negative scan. Another patient showed excellent targeting of gallium-negative sites in the liver and bone. The bone involvement was not known prior to the antibody study and was subsequently confirmed by a bone scan. Additional sites of MoAb localization could not be followed in this group, since most patients went on to radioimmunotherapy immediately following the {sup 99m}Tc-LL2 study. However, these initial results suggest that this new {sup 99m}Tc-labelled antibody imaging kit should be further investigated for its potential role in the staging and follow-up of lymphoma patients. (orig.).

  3. Labelling of 5-ethyl-5-phenylbarbituric acid with Technetium-99m: biodistribution study in Swiss mice

    The 5-ethyl-5-phenylbarbituric acid (phenobarbital) is used as a sedative, hypnotic and anticonvulsant drug. We decided to label it with technetium-99m. In order to determine the optimal conditions, different concentrations of this drug were incubated with various stannous chloride solutions. Then, 99mTc was added and chromatography was performed using 0.9% NaCl solution, acetone and n-butyl alcohol as the mobile phase. Using a solution of 0.01 mg/ml stannous chloride and 1.0 mg/ml phenobarbital over 92% of the radioactivity bound to phenobarbital 99mTc-phenobarbital. In the biodistribution study, 99mTc-phenobarbital was administered in mice intraperitoneal. The main uptake of the labeled drug was in the liver, blood, kidneys, spleen and stomach. The phenobarbital is also used as anesthetic drug in animals. Earlier studies confirm that this drug can dislocate the adult worms of Schistosoma mansoni to mesenteric vein towards the liver and portal vein, so that we used infected animals, radioactivity was not found in isolated worms and we can conclude that the phenobarbital has an indirect action in relation to the displacement of the worms. (author)

  4. Study on technetium-99m labeling of graphene oxide nanosheets through click chemistry-99mTc labeling of graphene oxide nanosheets

    江大卫; 彭程; 孙艳红; 贾丽娜; 李剑波; 张岚

    2015-01-01

    Graphene oxide (GO) nanosheets possess several advantages, such as a large surface, outstanding bio-compatibility, and straightforward chemical modification capability. They also have great potential as a drug-carrier. In this article, we radiolabeled GO nanosheets with 99mTc, which satisfies the potential needs of micro-SPECT imaging probes in pre-clinical and clinical research. GO nanosheets were synthesized through the modified Hummers’ method, then GO nanosheets with azide group covalently functionalized in two steps were conjugated to DOTA (1,4,7,10-tetraazacyclododecane-N,N0,N00,N000-tetraacetic acid) and functionalized with an alkynyl group by means of click chemistry. Then through the addition and reduction of technetium-99m, the 99mTc-DOTA-GO were attained. DOTA-conjugated GOs with lateral dimensions of 500–600 nm were synthe-sized. Both atomic force microscopy (AFM) and FT-IR were performed to characterize the GO-DOTA. Labeling efficiency of GO-DOTA with 99mTc was>90%and radiochemical purities were>96%with purification. We successfully synthesized graphene oxide derivatives, DOTA-conjugated GOs, via Click Chemistry, and it was labeled with 99mTc for SPECT imaging. High radiolabeling efficiency makes GO nanosheets suitable platforms for future molecular imaging research.

  5. Optimized localization of bacterial infections with technetium-99m labelled human immunoglobulin after protein charge selection

    Welling, M. (Dept. of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden (Netherlands)); Feitsma, H.I.J. (Dept. of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden (Netherlands)); Calame, W. (Dept. of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden (Netherlands)); Ensing, G.J. (Mallinckrodt Medical, Petten (Netherlands)); Goedemans, W. (Mallinckrodt Medical, Petten (Netherlands)); Pauwels, E.K.J. (Dept. of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden (Netherlands))

    1994-10-01

    To improve the scintigraphic detection of bacterial infections a protein charge-purified fraction of polyclonal human immunoglobulin was applied as a radiopharmaceutical. This purification was achieved by attaching the immunoglobulin to an anion-exchanger column and by obtaining the column-bound fraction with buffer. The binding to bacteria in vitro and the target to non-target ratios of an experimental thigh infection with Staphylococcus aureus or Klebsiella pneumoniae in mice were evaluated to compare the purified and the unpurified immunoglobulin. The percentage of binding to all gram-positive and gram-negative bacteria used in this study was significantly (P<0.03) higher for the purified than for the unpurified immunoglobulin. For the in vivo study, mice were infected in the thigh muscle with Staph. aureus or K. pneumoniae. After 18 h 0.1 mg of technetium-99m labelled polyclonal immunoglobulin or [sup 99m]Tc-labelled protein charge-purified polyclonal human immunoglobulin was administered intravenously. At all time intervals the target (infected thighs) to non-target (non-infected thighs) ratios for both infections were significantly higher (P<0.03) for protein charge-purified polyclonal immunoglobulin than for unpurified polyclonal human immunoglobulin. Already within 1 h the infected tissues could be detected by the purified immunoglobulin. It is concluded that [sup 99m]Tc-labelled protein charge-purified immunoglobulin localizes both a gram-positive and a gram-negative thigh infection more intensely and faster than [sup 99m]Tc-labelled unpurified immunoglobulin. (orig.)

  6. Technetium-99m labelling of the IOR CEA 1 monoclonal antibody: evaluation of different methods

    Gano, L.; Fernandes, C.; Patricio, L. [Inst. Tecnologico Nuclear, Sacavem (Portugal); Cantinho, G.; Santos, A.I.; Pena, H. [F.M.L., Lisboa (Portugal). Inst. Medicina Nuclear; Vieira, R.; Salgado, L. [IPOFG, Lisboa (Portugal). Servico Medicina Nuclear

    1997-09-01

    Aim: The aim of this study was to investigate the in vivo and in vitro properties of {sup 99m}Tc labelled monoclonal antibody, IOR CEA 1 when radiolabelled by different methods. Methods: To achieve that purpose IOR CEA was directly radiolabelled via 2-mercaptoethanol (2-Me) and stannous ion (SnCl{sub 2}) reduction and indirectly via the 2-iminothiolane (2-Im) conjugation. The resulting {sup 99m}Tc-MoAbs were analysed for number of free sulfhydryl groups, chemical and radiochemical purity (checked by HPLC and SDS PAGE), immunoreactivity and biological distribution in mice. Results: Experimental results indicated a similar radiochemical purity and immunoreactivity for direct labelling methods and a decrease of both for 2-Im method. 2-Me antibody reduction led to a high antibody fragmentation as indicated by non-denaturing SDS PAGE analysis. Nevertheless SnCl{sub 2} and 2-Im labels revealed lower in vivo stability. Conclusion: {sup 99m}Tc-(2-Me) IOR CEA presented favourable in vitro and in vivo properties. Therefore this label was compared to {sup 99m}Tc-monoclonal antibody BW 431/26. Similar characteristics were found. Clinical studies also revealed identical biodistribution profile. (orig.) [Deutsch] Ziel: Ziel der vorliegenden Studie war die Untersuchung der in vitro und in vivo Eigenschaften Technetium-markierter monoklonaler Antikoerper. Methoden: Hierzu wurde IOR CEA 1 entweder direkt, nach Reduktion mit 2-Mercaptoethanol (2-Me) bzw. Zinn(II)chlorid (SnCl{sub 2}), oder indirekt nach Konjugation mit 2-Iminothiolan (2-Im) markiert. Die Integritaet des reduzierten bzw. konjugierten Antikoerpers wurde mittels Bindungsassays und Elektrophorese ermittelt. Die radiochemischen Ausbeuten bzw. Reinheiten wurden chromatographisch bestimmt. Die pharmakokinetischen Eigenschaften von {sup 99m}Tc-IOR CEA 1 wurden tierexperimentell im Vergleich zu {sup 99m}Tc-BW 431/26 ermittelt. In einer ersten Studie wurden {sup 99m}Tc-(2-Me-)IOR CEA 1 und {sup 99m}Tc-BW 431/26 verglichen

  7. Scintigraphic study of gastrointestinal transit and disintegration sites of mesalazine tablets labelled with technetium 99m

    Sciarretta, G.; Furno, A.; Mazzoni, M.; Ferrieri, A.; Malaguti, P. (Ospedale Maggiore, Bologna (Italy))

    1993-09-01

    Tablets of mesalazine covered with a pH-dependent coating, labelled by an original technique with technetium-99m, were administered to 12 patients, 9 with Crohn's disease, 3 of which recurrent, 1 with ulcerative colitis, and 2 with irritable bowel syndrome, with the aim of verifying in vivo the intestinal site of disintegration and how the contents spread throughout the intestine. In all cases the tablet was broken down in the distal ileum at extremely variable intervals, from 5 to 27 h, and the contents spread into the nearby loops and into the colon. The notable differences in the residence time of the whole tablet in the ileum can be explained by differences in adhesion the inflamed mucosa and by a lower pH in the part of the ileum affected by the disease. 7 refs., 2 figs., 1 tab.

  8. Scintigraphic study of gastrointestinal transit and disintegration sites of mesalazine tablets labelled with technetium 99m

    Tablets of mesalazine covered with a pH-dependent coating, labelled by an original technique with technetium-99m, were administered to 12 patients, 9 with Crohn's disease, 3 of which recurrent, 1 with ulcerative colitis, and 2 with irritable bowel syndrome, with the aim of verifying in vivo the intestinal site of disintegration and how the contents spread throughout the intestine. In all cases the tablet was broken down in the distal ileum at extremely variable intervals, from 5 to 27 h, and the contents spread into the nearby loops and into the colon. The notable differences in the residence time of the whole tablet in the ileum can be explained by differences in adhesion the inflamed mucosa and by a lower pH in the part of the ileum affected by the disease. 7 refs., 2 figs., 1 tab

  9. Assessment of the effect of phytic acid on the labeling of blood cells and plasma proteins with Technetium-99m

    Blood elements labeled with technetium-99m (99m Tc) have been used in various procedures in nuclear medicine. We have investigated if phytic acid (PHY) could alter the labeling of blood elements with 99m Tc. Blood was incubated with different concentrations of PHY. Stannous chloride and 99mTc, as sodium pertechnetate, were added. Blood was centrifuged and plasma (P) and blood cell (BC) were isolated. Samples of P and BC were also precipitated with trichloroacetic acid and centrifuged, and insoluble (IF) and soluble (SF) fractions were separated. The percentages of radioactivity (%ATI) in BC, IF-P and IF-BC were calculated. The %ATI decreased significantly (p 99m Tc with possible undesirable effects, it is relevant to verify the necessity to repeat the examination and to evaluate the increase of the radiation dose to the patient. (author)

  10. Evaluation of technetium-99m/rhenium labelled nucleoside analogues as potential radiotracers in oncology

    cancer cells this technetium thymidine complex revealed a low internalisation of 0.03 ± 0.01%ID/(mg/mL). Under the same conditions the [3H]thymidine exhibited an uptake of 1.50 ± 0.02%lD/(mg/mL). In order to gain potency and selectivity for HSV1-TK, the corresponding 5'-carboxamide 5-ethyl-2', 5'-dideoxyuridine was synthesized. The synthesis of the ligand was performed in seven steps from 2'-deoxyuridine. This ligand was then successfully labelled with the fac-M(CO)3-core (M = 99mTc, Re). The rhenium complex was found to be a selective competitive inhibitor of HSV1-TK (Ki = 4.56 ± 0.11 μM). Although the cellular uptake of the technetium 2'-deoxyurine complex (0.10 ± 0.01%ID/(mg/mL)) was better than its corresponding technetium thymidine complex, it is still very low compared to thymidine uptake. The second aspect of this work was to develop nucleoside derivatives labelled with technetium-99m/rhenium tricarbonyl core capable of acting as substrates for human cytosolic thymidine kinase (hTKl). hTKl is a target of choice to evaluate cell proliferation due to its overexpression in a variety of cancer cells. [18F]Fluorothymidine [18F]FLT), which acts as a hTKl substrate, has emerged as a very efficient PET tracer for the monitoring of cell proliferation. Our aim was to develop a SPET tracer with the same mode of action as [18F]FLT. We prepared a set of technetium-99m/rhenium complexes of N3 thymidine derivatives with different overall charges (+1, 0 and -1) and variable spacer lengths. The complexes with different overall charges had the same spacer length between chelating system and thymidine moiety (two carbons spacer) while the complexes with different spacer lengths (2, 3, 5 and 10) were all neutral. These compounds were tested for their substrate activity with respect to recombinant hTKl. The phosphorylation rates of neutral and negative complexes were found to be similar, ranging between 15-16% with respect to thymidine (100%) whereas the phosphorylation rate of

  11. Technetium-99m labelled fluconazole and antimicrobial peptides for imaging of Candida albicans and Aspergillus fumigatus infections

    The aim of this study was to investigate whether technetium-99m labelled fluconazole can distinguish fungal from bacterial infections. Fluconazole was labelled with 99mTc and radiochemical analysis showed less than 5% impurities. The labelling solution was injected into animals with experimental infections. For comparison, we used two peptides for infection detection, i.e. UBI 29-41 and hLF 1-11, and human IgG, all labelled with 99mTc. Mice were infected with Candida albicans or injected with heat-killed C. albicans or lipopolysaccharides to induce sterile inflammation. Also, mice were infected with Staphylococcus aureus or Klebsiella pneumoniae. Next, accumulation of 99mTc-fluconazole and 99mTc-labelled peptides/IgG at affected sites was determined scintigraphically. 99mTc-fluconazole detected C. albicans infections (T/NT ratio=3.6±0.47) without visualising bacterial infections (T/NT ratio=1.3±0.04) or sterile inflammatory processes (heat-killed C. albicans: T/NT ratio=1.3±0.2; lipopolysaccharide: T/NT ratio=1.4±0.1). C. albicans infections were already seen within the first hour after injection of 99mTc-fluconazole (T/NT ratio=3.1±0.2). A good correlation (R2=0.864; P99mTc-UBI 29-41 and 99mTc-hLF 1-11 were able to distinguish C. albicans infections from sterile inflammatory processes in mice, these 99mTc-labelled peptides did not distinguish these fungal infections from bacterial infections. It is concluded that 99mTc-fluconazole distinguishes infections with C. albicans from bacterial infections and sterile inflammations. (orig.)

  12. Technetium-99m labelled fluconazole and antimicrobial peptides for imaging of Candida albicans and Aspergillus fumigatus infections

    Lupetti, Antonella [Department of Infectious Diseases, Leiden University Medical Center (LUMC), Leiden (Netherlands); Dipartimento di Patologia Sperimentale, Biotecnologie Mediche, Univ. di Pisa (Italy); Welling, Mick M. [Department of Radiology, Division of Nuclear Medicine, LUMC, Leiden (Netherlands); Mazzi, Ulderico [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova (Italy); Nibbering, Peter H. [Department of Infectious Diseases, Leiden University Medical Center (LUMC), Leiden (Netherlands); Pauwels, Ernest K.J. [Department of Radiology, Division of Nuclear Medicine, LUMC, Leiden (Netherlands); Department of Radiology, Leiden University Medical Center (LUMC) (Netherlands)

    2002-05-01

    The aim of this study was to investigate whether technetium-99m labelled fluconazole can distinguish fungal from bacterial infections. Fluconazole was labelled with {sup 99m}Tc and radiochemical analysis showed less than 5% impurities. The labelling solution was injected into animals with experimental infections. For comparison, we used two peptides for infection detection, i.e. UBI 29-41 and hLF 1-11, and human IgG, all labelled with {sup 99m}Tc. Mice were infected with Candida albicans or injected with heat-killed C. albicans or lipopolysaccharides to induce sterile inflammation. Also, mice were infected with Staphylococcus aureus or Klebsiella pneumoniae. Next, accumulation of {sup 99m}Tc-fluconazole and {sup 99m}Tc-labelled peptides/IgG at affected sites was determined scintigraphically. {sup 99m}Tc-fluconazole detected C. albicans infections (T/NT ratio=3.6{+-}0.47) without visualising bacterial infections (T/NT ratio=1.3{+-}0.04) or sterile inflammatory processes (heat-killed C. albicans: T/NT ratio=1.3{+-}0.2; lipopolysaccharide: T/NT ratio=1.4{+-}0.1). C. albicans infections were already seen within the first hour after injection of {sup 99m}Tc-fluconazole (T/NT ratio=3.1{+-}0.2). A good correlation (R{sup 2}=0.864; P<0.05) between T/NT ratios for this tracer and the number of viable C. albicans was found. Although {sup 99m}Tc-UBI 29-41 and {sup 99m}Tc-hLF 1-11 were able to distinguish C. albicans infections from sterile inflammatory processes in mice, these {sup 99m}Tc-labelled peptides did not distinguish these fungal infections from bacterial infections. It is concluded that {sup 99m}Tc-fluconazole distinguishes infections with C. albicans from bacterial infections and sterile inflammations. (orig.)

  13. Study of factors that interfere in the labelling process of erythrocytes and plasma proteins with Technetium-99m

    The labelling of red blood cells (RBC) with technetium-99m (Tc-99m) depends on several factors, as the stannous ion (Sn++) concentration, time, temperature, the presence of plasma proteins (PP) and others. However the Sn++ concentration seems to be the most important factor; probably because the uptake of this reducing agent by RBC is limited. The excess of Sn++ in extracellular medium can determine the labelling of PP. the modifications of RBC at 50 deg C described in the literature, the possibility of labelling RBC with Tc-99m at this temperature and experimental results obtained made it possible to perform spleen selective scintigraphy through a simple technique with few manipulations. The effect of gentamicin, nifedipine and verapamil in the labelling of RBC and plasma proteins with Tc-99m was studied because of similarities between Ca++ and Sn++. The results show that, under some conditions, these drugs are capable to alter this Tc-99m incorporation. The modification of the ionic distribution determined by these drugs or the blockage of Sn++ and/or Tc-99m or the fact that they bind theirselves to plasma proteins, or the possibility of the labelling of these drugs, are factors that can interfere in the labelling process of red blood cells and plasma proteins with Tc-99m. (author)

  14. Pharmacokinetics of labelled compounds with technetium-99m and samarium-153

    The purpose of this investigation was to establish the different pharmacokinetics parameters of the main radiopharmaceuticals labeled with technetium-99m and samarium-153. These parameters could be subsequently used as reference to compare other products with the same use. Mathematical models and a computerized pharmacokinetic program were used to this purpose. A biodistribution study in quadruplicate and/or quintuplicate was conducted for each radiopharmaceutical, data was was obtained in injection dose percentages. The biodistribution study involved the injection of a predetermined dose of the radiopharmaceutical into animals (rats or mice), which were subsequently put away at different time intervals, removing the relevant organs. Activity in each organ was read by means of a well-type NaI scintillation counter, data obtained in activity counts was transformed into injection dose percentages. Based on these percentages, the mathematical model was constructed and the pharmacokinetic parameters were obtained using the computerized program Expo 2 v. 1, which is written in C language and works in windows. Analyzing the results obtained, we can conclude that the use of the Expo 2 v. 1 program for a bi compartmental analysis allowed us to obtain reliable pharmacokinetic parameters which describe what happens in the organism when the radiopharmaceutical passes from the central compartment to the peripheral one and vice versa

  15. 99m technetium labelled heparin: potential value as a tracer of heparin activity in pharmacokinetic and biodistribution studies

    Pharmacokinetics and biodistribution of 99m Technetium (sup(99m)Tc) labelled heparin were studied to assess its value as a tracer of heparin kinetics in comparison with unlabelled heparin. In vitro, the stability and labelling efficiency (98%) of the labelled drug were excellent and elution was minimal. In vivo, after I.V. infusion of the drug, there was no difference in the same animal between anticoagulant activity measurements and radioactive countings, both displaying a plasmatic biexponential pattern (T1=2.9 minutes, T2=76 minutes). Biodistribution studies showed primarily liver, spleen and kidney accumulation, with no thyroid uptake. The advantages of this technetium labelling may therefore be used for the heparin drug in various experimental and pathological situations even in humans

  16. Preparation of nanocolloids based on modified DTPA molecule labeled with technetium-99M

    Full text: The method for preparation of new nanocolloid chemical systems based on modified diethylene triamine pentaacetic acid molecule has been elaborated in this work. Optimal method of sentinel lymph mode detection considers the use of colloid nanomaterials labled with technetium-99m for sintigraphic or radiometric detection of mode localization. The result of dynamic scintigraphic research showed that after being injected the substance is actively accumulated into lymphatic system

  17. Technetium-99m-human fibrinogen

    Exogenous fibrinogen has been successfully labeled with /sup 99m/Tc using a modified electrolytic method. The exact labeling mechanism has not been determined. Experimental data suggest that the labeling process of /99m/Tc-fibrinogen is quite similar to that of /sup 99m/Tc-human serum albumin as reported earlier by Benjamin. Technetium-99m-fibrinogen is stable in human plasma or in 1 percent buffered human serum albumin. A binding efficiency of 76 percent has been achieved with approximately 25 percent clottable protein. The entire labeling procedure requires less than 1 hr of preparation time. This short labeling time in a closed system may allow development of a practical method for labeling autologous fibrinogen, thus eliminating the risk of hepatitis transmission. (U.S.)

  18. Technetium-99m-labeled stealth pH-sensitive liposomes: a new strategy to identify infection in experimental model

    The diagnosis of inflammatory and infectious processes is an important goal in medicine. The use of radiopharmaceuticals for identification of inflammation and infection foci has received considerable attention. The aim of this work was to evaluate the uptake and the imaging potential of stealth pH-sensitive liposomes radiolabelled with 99mTechnetium (99mTc) to identify infection sites in mice. The liposomes containing glutathione were labeled with 99mTc-Hexamethyl propyleneamine oxime (HMPAO) complex. The 99mTc-labeled stealth pH-sensitive liposomes (99mTc-SpHL) were injected in mice bearing infection in the right thigh muscle induced by Staphylococcus aureus. Biodistribution studies and scintigraphic imaging were performed at different times after injection of radiopharmaceutical. The 99'mTc-SpHL was significantly uptaken by abscess when compared to the respective control. The abscess was visualized as early as 0.5 hours after injection of 99mTc-SpHL becoming more prominent with the time. These results indicate that 99'mTc-SpHL is a promising radiopharmaceutical for visualizing infection foci in patients. (author)

  19. Synthesis and preliminary biological evaluation of a technetium-99m labeled thymidine analog

    Chun Xiong Lu; Zheng Wu Wang; Quan Fu Jiang; Jie Tang; Cheng Tan; Jian Kang Zhang

    2011-01-01

    The synthesis and labeling of 99mTc-N3-{N'-[2-sulfanyl-ethylamino)acetyl]-2-aminoethyl-sulfanyl-l-hexanamide}thymidine (99mTc-NHT) were studied. In the presence of sodium glucoheptonate (GH) and ethylene diamine tetraacetic acid (EDTA), 99mTc-NHT was obtained by using bisaminoethanethiol (N2S2) as a bifunctional coupling agent. The radiochemical purity of the 99mTc-NHT was over 95%. Biodistribution of 99mTc-NHT was performed in hepatoma HepA tumor-bearing mice. At 2 h p.i., the ratios of tumor-to-muscle, tumor-to-bone and tumor-to-blood were 4.41 ± 0.32, 2.45 ± 0.24 and 1.51 ±0.18, respectively.

  20. Contribution to the study of the red blood cells labelled with chromium-51 and technetium-99 m

    Although the bindings of Cr-51 and Tc-99 m were both in the β chain of hemoglobin molecule, the results obtained after previous incubations of the RBC with chromium and technetium, and the determinations of the efficiency of the labeling of RBC showed that the points of fixing of chromium and technetium with β chain of hemoglobin were probably different. The observations through the optic microscope allowed the verification that, at the concentration of 100 mg/ml of Cr-50, there were morphologic in the RBC. These modifications were not found after the other treatments. The comparison between scintigraphy obtained with Tc-99 m or Cr-51 RBC suggested that the technique which employs Tc-99 m can be more adequate than the one with Cr-51. (author)

  1. Limited value of technetium 99m-labeled red cell scintigraphy in localization of lower gastrointestinal bleeding

    The aim of this study was to assess the accuracy of technetium 99m-labeled red cell scintigraphy in localizing the site of lower gastrointestinal bleeding. The outcome of 203 patients undergoing technetium 99m-labeled red cell scintigraphy was reviewed, and the scan result was compared with the true site of bleeding. The true site of bleeding was determined by other methods including angiography and surgical pathology. Fifty-two scans (26%) were positive and indicated a specific site of bleeding. A definitive bleeding site was identified in 22 patients by other means and correlated with the technetium scan in only 9 cases. The nuclear scan was incorrect in the remaining 13 cases, implying a localization error of 25% (13 of 52). A subgroup of 19 patients with a positive scan underwent a surgical procedure directed by the nuclear scan. Eight of these 12 patients had incorrect surgical procedures based upon findings of more definitive tests, indicating a surgical error of 42% (8 of 19). We conclude that the technetium 99m-labeled red cell scan's ability to accurately localize the site of lower gastrointestinal bleeding is limited. Furthermore, performing a surgical procedure that relies exclusively on localization by red cell scintigraphy will produce an undesirable result in at least 42% of patients

  2. Limited value of technetium 99m-labeled red cell scintigraphy in localization of lower gastrointestinal bleeding

    Hunter, J.M.; Pezim, M.E. (Univ. of British Columbia, Vancouver (Canada))

    1990-05-01

    The aim of this study was to assess the accuracy of technetium 99m-labeled red cell scintigraphy in localizing the site of lower gastrointestinal bleeding. The outcome of 203 patients undergoing technetium 99m-labeled red cell scintigraphy was reviewed, and the scan result was compared with the true site of bleeding. The true site of bleeding was determined by other methods including angiography and surgical pathology. Fifty-two scans (26%) were positive and indicated a specific site of bleeding. A definitive bleeding site was identified in 22 patients by other means and correlated with the technetium scan in only 9 cases. The nuclear scan was incorrect in the remaining 13 cases, implying a localization error of 25% (13 of 52). A subgroup of 19 patients with a positive scan underwent a surgical procedure directed by the nuclear scan. Eight of these 12 patients had incorrect surgical procedures based upon findings of more definitive tests, indicating a surgical error of 42% (8 of 19). We conclude that the technetium 99m-labeled red cell scan's ability to accurately localize the site of lower gastrointestinal bleeding is limited. Furthermore, performing a surgical procedure that relies exclusively on localization by red cell scintigraphy will produce an undesirable result in at least 42% of patients.

  3. In vivo Behaviour of Technetium-99m Labelled N, N' -bis-(1-Carboxy-2-Mercaptoethyl)-Ethylenediamine(EC)

    N,N-bis-(1-carboxy-2-mercaptoethyl)ethylenediamine(EC), a precursor for potential new generation technetium radiopharmaceutical for renal function studies, was synthesized in simple two step method. High percentage labelling (90%) was achieved during its radiopharmaceutical preparation with Tc-99m pertechnetate in presence of stannous chloride. Its renal clearance in experimental animals was found to be better than that of 131 I-ortho-iodohippuric acid and comparable to that of the recently developed 99m Tc-MAG3. 13 refs., 7 tables (author)

  4. Technetium-99m labeled somatostatin and analogs: synthesis, characterization and in vivo evaluation

    Technetium-99m complexes of somatostatin and analogs were synthesized following the introduction of sulfhydryl groups with 2-iminothiolane (Traut's Reagent). In rats the complex was taken up by the liver, kidneys, adrenals, lungs and the pancreas. Analysis of urine samples of treated rats showed that the radiochemicals have reasonably good in vivo stability. This implies that the complexes may be potentially useful for biochemical characterization of somatostatin receptors and also in scintigraphic detection of somatostatin receptor positive tumors, especially for metastatic deposits in patients on somatostatin therapy. (Author)

  5. Technetium-99m labeled somatostatin and analogs: synthesis, characterization and in vivo evaluation

    Technetium-99m complexes of somatostatin and analogs were synthesized following the introduction of sulfhydryl groups with 2-iminothiolane (Traut's Reagent). In rats the complex was taken up by the liver, kidneys, adrenals, lungs and the pancreas. Analysis of urine samples of treated rats showed that the radiochemicals have reasonably good in vivo stability. This implies that the complexes may be potentially useful for biochemical characterization of somatostatin receptors and also in scintigraphic detection of somatostatin receptor positive tumors, especially for metastatic deposits in patients on somatostatin therapy. (author)

  6. Technetium-99m labelling of the IOR CEA 1 monoclonal antibody: evaluation of different methods

    Aim: The aim of this study was to investigate the in vivo and in vitro properties of 99mTc labelled monoclonal antibody, IOR CEA 1 when radiolabelled by different methods. Methods: To achieve that purpose IOR CEA was directly radiolabelled via 2-mercaptoethanol (2-Me) and stannous ion (SnCl2) reduction and indirectly via the 2-iminothiolane (2-Im) conjugation. The resulting 99mTc-MoAbs were analysed for number of free sulfhydryl groups, chemical and radiochemical purity (checked by HPLC and SDS PAGE), immunoreactivity and biological distribution in mice. Results: Experimental results indicated a similar radiochemical purity and immunoreactivity for direct labelling methods and a decrease of both for 2-Im method. 2-Me antibody reduction led to a high antibody fragmentation as indicated by non-denaturing SDS PAGE analysis. Nevertheless SnCl2 and 2-Im labels revealed lower in vivo stability. Conclusion: 99mTc-(2-Me) IOR CEA presented favourable in vitro and in vivo properties. Therefore this label was compared to 99mTc-monoclonal antibody BW 431/26. Similar characteristics were found. Clinical studies also revealed identical biodistribution profile. (orig.)

  7. Assessment of the effect of phytic acid on the labeling of blood cells and plasma proteins with Technetium-99m

    Lima-Filho, Guilherme L.; Freitas, Rosimeire S.; Moreno, Silvana R.F.; Boasquevisque, Edson M.; Bernardo-Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria]. E-mail: gllf@hotmail.com; Lima, Glaydes M.T. [Pernambuco Univ., Recife, PE (Brazil). Hospital das Clinicas; Catanho, Maria T.J.A. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    2002-07-01

    Blood elements labeled with technetium-99m ({sup 99m} Tc) have been used in various procedures in nuclear medicine. We have investigated if phytic acid (PHY) could alter the labeling of blood elements with {sup 99m} Tc. Blood was incubated with different concentrations of PHY. Stannous chloride and {sup 99m}Tc, as sodium pertechnetate, were added. Blood was centrifuged and plasma (P) and blood cell (BC) were isolated. Samples of P and BC were also precipitated with trichloroacetic acid and centrifuged, and insoluble (IF) and soluble (SF) fractions were separated. The percentages of radioactivity (%ATI) in BC, IF-P and IF-BC were calculated. The %ATI decreased significantly (p < 0.05) in BC (95.08 {+-}1.94 to 80.68 {+-} 3.35), in IF-P (74.42 {+-}4.50 to 39.94{+-} 5.51) and in IF-BC (89.91{+-} 3.91 to 79.54 {+-} 5.42) in presence of PHY. These results suggest that the chelating property of PHY can modify the labeling of the BC, although other effects of PHY could be responsible. As PHY is found in many food and it could alter the labeling of blood elements with {sup 99m} Tc with possible undesirable effects, it is relevant to verify the necessity to repeat the examination and to evaluate the increase of the radiation dose to the patient. (author)

  8. Experimental study of radiopharmaceuticals based on technetium-99m labeled derivative of glucose for tumor diagnosis

    Zeltchan, R.; Medvedeva, A.; Sinilkin, I.; Bragina, O.; Chernov, V.; Stasyuk, E.; Rogov, A.; Il'ina, E.; Larionova, L.; Skuridin, V.; Dergilev, A.

    2016-06-01

    Purpose: to study the potential utility of 1-thio-D-glucose labeled with 99mTc for cancer imaging in laboratory animals. Materials and method: the study was carried out in cell cultures of normal CHO (Chinese hamster ovary cells CHO) and malignant tissues MCF-7 (human breast adenocarcinoma MCF-7). To evaluate the uptake of 99mTc-1-thio-D-glucose in normal and tumor tissue cells, 25 MBq of 1-thio-D-glucose labeled with 99mTc was added to the vials with 3 million cells and incubated for 30 minutes at room temperature. After centrifugation of the vials with cells, the supernatant was removed. Radioactivity in vials with normal and tumor cells was then measured. In addition, the study included 40 mice of C57B 1/6j lines with tumor lesion of the right femur. For neoplastic lesions, Lewis lung carcinoma model was used. Following anesthesia, mice were injected intravenously with 25MBq of 99mTc-1-thio-D-glucose. Planar scintigraphy was performed 15 minutes later in a matrix of 512x512 pixels for 5 minutes. Results: when measuring the radioactivity of normal and malignant cells after incubation with 99mTc-1-thio-D- glucose, it was found that the radioactivity of malignant cells was higher than that of normal cells. The mean values of radioactivity levels in normal and malignant cells were 0.3±0.15MBq and 1.07±0.6MBq, respectively. All examined animals had increased accumulation of 99mTc-1-thio- D-glucose at the tumor site. The accumulation of 99mTc-1-thio-D-glucose in the tumor was on average twice as high as compared to the symmetric region. Conclusion: The present study demonstrated that 99mTc-1-thio-D-glucose is a prospective radiopharmaceutical for cancer visualization. In addition, high accumulation of 99mTc-1-thio-D-glucose in the culture of cancer cells and in tumor tissue of animals demonstrates tumor tropism of the radiopharmaceutical.

  9. Study of potential utility of new radiopharmaceuticals based on technetium-99m labeled derivative of glucose

    Zeltchan, R.; Medvedeva, A.; Sinilkin, I.; Chernov, V.; Stasyuk, E.; Rogov, A.; Il'ina, E.; Larionova, L.; Skuridin, V.

    2016-08-01

    Purpose: to study the potential utility of 1-thio-D-glucose labeled with 99mTc for cancer imaging in laboratory animals. Materials and method: the study was carried out in cell cultures of normal CHO (Chinese hamster ovary cells CHO) and malignant tissues MCF-7 (human breast adenocarcinoma MCF-7). To evaluate the uptake of 99mTc-1-thio-D-glucose in normal and tumor tissue cells, 25 MBq of 1-thio-D-glucose labeled with 99mTc was added to the vials with 3 million cells and incubated for 30 min at room temperature. After centrifugation of the vials with cells, the supernatant was removed. The radioactivity in vials with normal and tumor cells was then measured. In addition, the study included 40 mice of C57B1/6j lines with tumor lesion of the right femur. For neoplastic lesions, Lewis lung carcinoma model was used. Following anesthesia, mice were injected intravenously with 25 MBq of 99mTc-1-thio-D-glucose. Planar scintigraphy was performed 15 minutes later in a matrix of 512x512 pixels for 5 min. Results: when measuring the radioactivity of normal and malignant cells after incubation with 99mTc-1-thio-D-glucose, it was found that the radioactivity of malignant cells was higher than that of normal cells. The mean values of radioactivity levels in normal and malignant cells were 0.3 ± 0.15 MBq and 1.07 ± 0.6 MBq, respectively. All examined animals had increased accumulation of 99mTc-1-thio-D-glucose at the tumor site. The accumulation of 99mTc-1-thio-D-glucose in the tumor was on average twice as high as compared to the symmetric region. Conclusion: The present study demonstrated that 99mTc-1-thio-D-glucose is a prospective radiopharmaceutical for cancer visualization. In addition, high accumulation of 99mTc-1-thio-D-glucose in the culture of cancer cells and in tumor tissue of animals demonstrates tumor tropism of the radiopharmaceutical.

  10. Assessment of the accumulation of technetium-99m labelled leukocytes in the treatment of the infections of vascular prosthesis

    The purpose of this is to evaluate the accumulation of technetium-99m-labelled leukocytes after change of vascular, dacron and infected prosthetic graft in arterial homo grafts harvested from multiorgan-procurement - with own computer program. In this paper 11 cases of aorto-ilio-femoral graft infection treated by the replacement of infected prosthesis with fresh, bifurcated, arterial homografts is presented. In all patients clinical investigations revealed vascular prosthesis infection with the rupture of vascular anastomoses between the prosthesis' branch and wall of artery that resulted with hemorrhage. The Duplex- Doppler ultrasound and the scintigraphy with use of technetium-labeled leucocytes were used in the diagnostic trial of infection and of the healing process of the arterial homografts.The area of the accumulation of 99mTc labelled leukocytes was evaluated with own computer programs. Positive clinical effect was obtained in all patients.The regression of infection after in situ replacement of the synthetic prosthesis with homograft was presented with the scintigraphic examination: in these patients the area of leukocytes accumulation decreased from 34±3 cm2 to 9±2cm2. The use of scintigraphy with 99mTc labelled leukocytes to evaluate the healing process of the arterial homografts in therapy of the prosthetic graft is a the accumulation of leucocytes is facilitation in the monitoring of regression of infection. (author)

  11. Radio-labeling of Ethambutol with Technetium-99m and its evaluation for detection of tuberculosis

    Several microbial, immunological, radiological and molecular investigations have been employed in the management of Tuberculosis (TB). Most of these investigations have proven their utility and value in routine clinical practice. But such investigations also have several limitations, like lack of high specificity and inability to detect the disease early. Radionuclide imaging may also play an important role in the management of tuberculosis, especially in early detection and localization of the disease. The present work is based on the use of a new radiopharmaceutical, Tc-99m Ethambutol to detect and locate TB at an early stage in any anatomical site. It may be noted that our laboratory has already carried out the radiocomplexation of Isoniazid with Tc-99m and evaluated it for specific diagnosis of TB. Ethambutol (EMB) was chosen as ligand because it is a specific anti-tubercular drug (interacts specifically with cell wall mycolic acid of Mycobacterium). Complexation of EMB with Tc-99m was standardized (Patent pending). Various pharmacokinetic parameters were studied in balb/c mice and New Zealand White Rabbits. Biological activity of labeled EMB was studied by Colony Forming Unit (CFU) assay of M.tuberculosis, on solid media (Middlebrook 7H10 Agar, DIFCO). Thigh models of localized TB lesion were developed in four rabbits by injecting 1.5 x 108 cells/0.5ml of Mycobacterium tuberculosis (Clinical Human Isolate) live bacteria in growing phase. The lesions were confirmed after 3 weeks of injection with the help of AFB staining and culture. The localization kinetics of the radiolabelled complex was studied in the developed animal model by injecting 70-75MBq of Tc-99m Ethambutol intravenously in the dorsal ear vein of rabbits and the images were acquired with a Gamma-camera (ECIL) at different time intervals following injection up to 24 hrs. Labeling efficiency of Tc-99m Ethambutol was consistently found to be more than 85% in the repeated experiments. Only 2-3.5% of

  12. Retention of technetium-99m in infectious foci in rats after release from technetium-99m labelled human non-specific polyclonal immunoglobulin G: a dual-label study with hydrazinonicotinamido and iminothiolano immunoglobulin

    In an effort to contribute to the understanding of the mechanism of uptake of technetium-99m labelled non-specific polyclonal human immunoglobulin G (hIgG) in inflammatory lesions we compared the tissue distribution of double-labelled 99mTc-hydrazinonicotinamido (HYNIC) hIgG-14C and 99mTc-iminothiolano hIgG-14C in groups of five Wistar rats with a Staphylococcus aureus infection of the left calf muscle between 2 h p.i. and 24 h p.i. The stability of the two double-labelled hIgG preparations was evaluated in vitro and in plasma in vivo by high-performance liquid chromatography (HPLC) analysis. At 24 h after injection of 99mTc-HYNIC-hIgG-14C the abscess uptake of 99mTc (1.5% ID/g±0.2% ID/g) was significantly higher (P14C uptake (1.0% ID/g±0.1% ID/g). After injection of 99mTc-iminothiolano hIgG-14C no significant difference (P=0.08) was found between the abscess uptake of the two radionuclides at 24 h p.i. (99mTc: 0.8% ID/g±0.1% ID/g; 14C: 0.90% ID/g±0.09% ID/g). HPLC analysis of plasma samples revealed release of 99mTc from both double-labelled immunoglobulin preparations. This phenomenon was more pronounced for iminothiolano hIgG than for HYNIC hIgG (43% vs 18%). In most tissues other than abscesses significant differences were also found between the 99mTc and the corresponding 14C uptake. Our results demonstrate that the chemical form in which 99mTc is bound to hIgG severely influences its release from hIgG and its retention in infections. (orig.). With 4 figs., 2 tabs

  13. Preparation and use of NHS-MAG3 for technetium-99m labeling of DNA

    The chelator mercaptoacetylglycylglycylglycine (MAG3) is one of several amidothiols that have been used successfully to radiolabel proteins and other molecules with 99mTc. Prior to radiolabeling, the sulfur in these amidothiols is usually protected by a benzoyl group (i.e. S-benzoyl MAG3) which requires extreme alkaline pH or boiling water temperatures for rapid deprotection. As a result, the benzoyl-protected chelator is radiolabeled prior to conjugation (i.e. preconjugation labeling) in the case of carriers such as proteins or polypeptides which cannot withstand harsh conditions. We have employed a simple, two-step, synthesis of the N-hydroxysuccinimide ester of MAG3 in which the sulfur is protected with an acetyl group (i.e. S-acetyl NHS-MAG3). A single-stranded amine-derivitized DNA was coupled with NHS-S-acetyl MAG3. Radiolabeling was accomplished at room temperature and neutral pH by transchelation from 99mTc-tartrate. In comparison to labeled SHNH-DNA, the labeled MAG3-DNA was unstable to cysteine transchelation, however, in contrast to SHNH-DNA, no evidence for serum protein binding of the labeled MAG3-DNA was observed. We conclude that the S-acetyl NHS MAG3 bifunctional chelator may prove to be an attractive alternative method of radiolabeling DNA and other biologically important molecules with 99mTc

  14. Quantitation of thrombogenicity of hemodialyzer with technetium-99m and indium-111 labeled platelets

    Dewanjee, M.K.; Kapadvanjwala, Mansoor; Ruzius, Kees; Serafini, A.N.; Zilleruelo, G.E.; Sfakianakis, G.N. (Miami Univ., FL (United States). School of Medicine Althin CD-Medical Inc., Miami Lakes, FL (United States))

    1993-07-01

    The platelet thromobogenicity of a hemodialyzer was quantified with [sup 99m]Tc- and [sup 111]In-labeled platelets. The platelets collected from blood of Beagle dogs, Yorkshire pigs and human volunteers were labeled with [sup 111]in-tropolone (detergent-free) and [sup 99m]Tc-HMPAO. Hemodialysis was performed with a hollow-fiber dialyzer (HFD) in a flow-loop, the temperature of which was maintained at 37[sup o]C, with flow-rates of 7, 150 and 270 mL/min; after dialysis, the HFD radioactivity was measured with an ionization chamber and imaged with a [gamma]-camera. The radioactivity of samples of hollow-fibers taken from the top, middle and bottom of the dialyzer was determined with a [gamma]-counter. The mean values of hemodialyzer-adherent platelet radioactivity were calculated for both radionuclides. The canine platelets were found to be more thrombogenic than porcine and human platelets. The adhesivity of porcine platelets to the biomaterial (cellulose-acetate) of the dialyzer approximated that of human platelets. The [sup 99m]Tc label underestimated the thrombus formation (P < 0.01 ). The dynamic processes of thrombosis and embolization from the hemodialyzer resulted in the large standard deviations around the mean values of the adherent thrombus. In spite of this limitation of the dynamic pathology, the quantitation of comparative throbogenicity with [sup 111]In- and [sup 99m]Tc-labeled platelets suggests that both radionuclides could be used for measurement of device-induced thrombogenicity and may provide an estimation of prosthesis-induced thrombogenicity of human platelets from animal studies. (Author).

  15. Preliminary studies of Technetium-99m-labeled antimyosin monoclonal antibody: development of radiopharmaceutical for cardiac evaluation

    Carvalho, Guilherme Luiz de Castro; Spencer, Patrick Jack; Muramoto, Emiko; Araujo, Elaine Bortoleti de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: glcarval@ipen.br

    2007-07-01

    In the acute myocardium infarction, the myocytes cell membrane loses its integrity, allowing the influx of extracellular macromolecules such as circulating antibody into the damaged cell. Specific antibodies to cardiac myosin can therefore bind to the acutely necrotic myocyte, allowing the noninvasive localization and dimension of myocardial infarction. Because of its favorable physical characteristics, low cost, and ready availability, technetium-99m ({sup 99m}Tc) is the radionuclide of choice for scintigraphy. The purpose of this work was to study the labeling of the antimyosin monoclonal antibody with ({sup 99m}Tc for development of a radiopharmaceutical with high sensitivity and specificity used in the diagnostic of the myocardial infarction. The intact monoclonal antibody (IgG{sub 1}) was reduced by treatment with dithiothreitol (DTT) with the consequent generation of free thiol groups (- SH), responsible for the labeling of the antibody with ({sup 99m}Tc. The radiochemical yield was determined using Sephadex G-25 column (PD-10). The percentage of ({sup 99m}Tc-antibody was 90,06% and after purification procedure the radiochemical yield was > 98%. The biodistribution studies showed low uptake in the stomach and thyroid at different times (1, 4 e 24 hours) representing a small amount of unbounded ({sup 99m}Tc and a good stability of the purified ({sup 99m}Tc-antibody. The uptake in the normal heart was relatively low as expected. Based on these results, we concluded that the direct labeling procedure applied to the antimyosin monoclonal antibody allowed the easy preparation of the radiopharmaceutical with good stability to be used in the noninvasive diagnostic of the myocardial infarction. (author)

  16. Optimized localization of bacterial infections with technetium-99m labelled human immunoglobulin after protein charge selection

    To improve the scintigraphic detection of bacterial infections a protein charge-purified fraction of polyclonal human immunoglobulin was applied as a radiopharmaceutical. This purification was achieved by attaching the immunoglobulin to an anion-exchanger column and by obtaining the column-bound fraction with buffer. The binding to bacteria in vitro and the target to non-target ratios of an experimental thigh infection with Staphylococcus aureus or Klebsiella pneumoniae in mice were evaluated to compare the purified and the unpurified immunoglobulin. The percentage of binding to all gram-positive and gram-negative bacteria used in this study was significantly (P99mTc-labelled protein charge-purified polyclonal human immunoglobulin was administered intravenously. At all time intervals the target (infected thighs) to non-target (non-infected thighs) ratios for both infections were significantly higher (P99mTc-labelled protein charge-purified immunoglobulin localizes both a gram-positive and a gram-negative thigh infection more intensely and faster than 99mTc-labelled unpurified immunoglobulin. (orig.)

  17. Synthesis, radiochemistry and biological evaluation of a new somatostatin analogue (SDZ 219-387) labelled with technetium-99m

    A new derivative of octreotide SDZ 219-387 [PnAO-(D)Phe1-octreotide] was synthesized, which binds specifically and with high affinity to somatostatin receptors in vitro (pKi=9.79±0.16). This new somatostatin analogue chelates technetium-99m under mild labelling conditions in good yields. The resulting [99mTc]SDZ 219-387 was stable up to 6 h after labelling and could be isolated in a pure radiochemical and chemical form by high-perfomance liquid chromatographic purification. The intravenous administration of purified [99mTc]SDZ 219-387 revealed that the radioligand was rapidly cleared from circulation, and tumour uptake of 0.38% ID/g was observed at 1.5 h post injection. [99mTc]SDZ 219-387 specifically interacted with somatostatin binding sites on the tumour. However, the radioligand is highly lipophilic and excreted mainly through the hepatobiliary system. As a consequence, [99mTc]SDZ 219-387 exhibits increased background activity and therefore is not appropriate for the in vivo visualization of somatostatin receptor-positive tumours and/or their metastases in the abdomen. (orig.)

  18. 99mTechnetium labelled vasoactive intestinal peptide analogue for rapid localization of tumours in humans

    In recent years, imaging tumours with receptor specific biomolecules has been the focus of increasing interest. VIP has a high affinity for specific receptors that are expressed in high density on a large number of malignant tumours. VIP was modified (TP 3654) without compromising its biological activity, and labelled with 99mTc. Pharmacokinetics and feasibility studies were performed in three normal volunteers and 11 patients with a history of cancer. Imaging was performed for up to two h post-injection. Within 24 h after injection of 99mTc-TP 3654 (10-15 mCi/5 μg), approximately 70% of the tracer cleared through the kidneys, and 20% through the liver. Blood clearance was rapid. No adverse reaction was noted in any subjects. All known tumours were clearly delineated within 20 min. Findings were compared with the results of 99mTc-MIBI, CT, MRI, or histology. There was concordance in nine patients. In the other two, only the VIP scan was positive for tumours known to express VIP receptors. The early results of imaging tumours with 99mTc-VIP are promising and warrant further studies. (author)

  19. Localization of lower gastrointestinal hemorrhage. Experience with red blood cells labeled in vitro with technetium Tc 99m

    Seventy-six patients clinically suspected of having lower gastrointestinal bleeding were studied by scintigraphy utilizing red blood cells labeled in vitro with technetium Tc 99m. Sixteen patients required emergency surgery; bleeding was accurately localized in 15 (94%). One patient (6%) had a normal scan. A 20-month mean follow-up of the 16 patients showed no recurrent bleeding. Of 60 patients not requiring emergency surgery, bleeding was localized in 11, but the bleeding ceased. Forty-nine of the 60 patients had normal scans and had no further hemorrhaging during hospitalization. A 21-month mean follow-up of 38 of the 49 patients showed no further bleeding episodes or surgical procedures in 29 patients; however, eight patients required surgical procedures, including seven for gastrointestinal malignancies. Scanning of red blood cells labeled in vitro with 99mTc is accurate and efficacious in localization of bleeding sites that require emergency surgery for lower gastrointestinal hemorrhage

  20. Dissemination of bacteria labeled with technetium-99m after laparotomy and abdominal insufflation with different CO2 pressures on rats

    Purpose: To asses the dissemination of bacteria labeled with technetium-99m (99mTc) from peritoneal cavity after different surgical procedures. Methods: Bacteria of the Escherichia coli species labeled with 99mTc were used in a concentration of 108 units of colony-makers for ml (UFC/ml) and 1 ml was inoculated through intra-peritoneal via. Forty-eight rats were divided into four groups: control, laparotomy, pneumoperitoneum with 10 mmHg and pneumoperitoneum with 20 mmHg of CO2. Procedures were performed 20 min after injection of the inoculum and lasted 30 min. Animals were sacrificed after six hours (Group 1) and 24 hours (Group 2). Samples of blood, liver and spleen were collected for radioactivity counting. Results: After six hours, indirect detection of the bacteria in different organs was uniform in all groups. After 24 hours, a larger detection of technetium was observed in the livers of animals of the group insufflated with 20 mmHg of CO2, when compared with those of control group (p<0.01). The other groups did not present statistically significant variations. Conclusions: The use of a higher intra-abdominal pressure was associated with a higher bacterial dissemination to the liver. The application of lower intra-abdominal pressures may be associated with a lower dissemination of the infectious status during laparoscopic approach of peritonitis status. (author)

  1. Effect of Ginkgo biloba on the labeling of blood elements with technetium-99m: in vitro study

    Silvana Ramos Farias Moreno

    2002-01-01

    Full Text Available Ginkgo biloba is the phytoterapic most used in popular medicine in the treatment of cerebral senescence. Red blood cells (RBC labeled with technetium-99m (Tc-99m is used for several evaluations in nuclear medicine. This labeling depends on a reducing agent, usually the stannous ion. Any drug, which alters the labeling of the tracer, could be expected to modify the disposition of the radiopharmaceutical. We have evaluated the influence of the Ginkgo biloba extract on the labeling of RBC and plasma proteins with Tc-99m. Blood was withdrawn and incubated with Ginkgo biloba extract (0; 0.004; 0.04; 0.4; 4; 20 and 40 mg/ml. Stannous chloride (1.2 ml/ml was added and, then, Tc-99m was added. Plasma (P and blood cells (RBC were isolated, also precipitated with trichloroacetic acid and soluble (SF and insoluble fractions (IF separated. The analysis of the results shows that there is a decrease in the radioactivity (from 97.7 ± 0.7 to 49.5 ± 3.9% in RBC with the drug (4 mg/ml. In the labeling process of RBC with Tc-99m, the stannous and pertechnetate ions pass though the membrane, so, we suggest that the Ginkgo biloba effect can be explained by (i an inhibition of the transport of these ions, (ii damage in membrane, (iii competition with the cited ions for the same binding sites, or (iv possible generation of reactive oxygen species that could oxidize the stannous ion.

  2. Preparation of lyophilized kit of HYNIC-[Tyr3]-Octreotate and labelling studies with 99m-Technetium

    The development of radiolabeled molecules with high specificity for an organ ar tumor has been contributed to the precise diagnostic in nuclear medicine. Somatostatin labeled derivatives constitutes a particular example of labeled peptide applied in the localization of neuroendocrine tumors. Nowadays, the 111In DTPA-octreotide is the radiopharmaceutical applied in diagnostic procedures for the visualization of tumors with high expression of somatostatin receptors. However, the 111-indium is a radionuclide that presents some limitations related to availability (cyclotron production), half-life (67 hours) and the emission of medium energy photons (171 keV e 245 keV), not favorable to the acquisition of images in SPECT (Single Photon Emission Computed Tomography). The favorable physical properties of the 99m-technetium (99mTc) make this radionuclide the more favorable to substitute the 111-indium on peptide labeling procedures. This work studied the preparation and labeling of a lyophilized kit of HYNIC-Tyr3-octreotate (HYNIC-octreotate) with 99mTc, base on previously described procedures and using tricine and EDDA (ethylendiaminediacetic acid) as coligands. It was studied the labeling parameters (incubation time, temperature, volume and perthecnetate activity) and the stability of the lyophilized preparation. Additionally, it was studied the influence of the pre-freezing using liquid nitrogen in the stability of the lyophilized preparation, as well as the influence of manitol in the labeling yield and biological distribution of the complex. The stability studies showed that the lyophilization using liquid nitrogen pre-freezing resulted in a lyophilized preparation with stability over 4 month when stored under refrigeration. The stability of the lyophilized preparation obtained without liquid nitrogen pre-freezing was similar.The labeling studies determined the best labeling conditions, resulting in a radiochemical yield superior than 90%. The use of manitol in the

  3. Technetium-99m labeled monoclonal antibodies in the detection of metastatic melanoma

    Twenty-six stage II/III malignant melanoma patients with 321 measurable metastatic lesions were imaged using Fab fragments of an IgG murine monoclonal antibody labeled specifically with 10-30 mCi Tc-99m with a bi-functional chelating method (NeoRx, Seattle, WA). There were no side effects or adverse reactions. Immunoscintigraphy demonstrated 66.6% of lesions larger than 1 cm and 92.5% of lesions larger than 3 cm. Most frequently detected metastases were in lymph nodes, subcutaneous areas, and bone. Of lesions less than 1 cm, 23.6% were detected if superficial cutaneous lesions were excluded. The smallest detectable lesion was 4 mm. Twenty-one additional clinically unsuspected sites were visualized in 12 of the 26 patients studied. Of these, 56% were confirmed as metastasis by other tests. There were apparent nonspecific localizations owing to other causes, including fracture, varicosities, skin abscess and pneumonitis. Increased experience in image analysis facilitates correct interpretation of these localizations. This study demonstrates that imaging with Tc-99m labeled antibody fragments detects melanoma lesions in organs routinely surveyed and in other areas not routinely assessed by other imaging techniques. The procedure is readily performed and safe. The principal advantage of the test is its ability to survey the entire body and all organs with a single test. Its principal limitation, in common with other diagnostic imaging procedures, is its poor sensitivity for detecting lesions less than 1 cm

  4. Imaging of metastatic melanoma utilising a technetium-99m labelled RGD-containing synthetic peptide

    Integrins are cell-surface glycoproteins found in different forms on all cells except erythrocytes. Integrins bind to cell adhesion molecules and to proteins found in the extracellular matrix. A tripeptidic sequence Arg-Gly-Asp (RGD) is often the primary site of recognition by integrins which are expressed on tumour cells and are responsible for tumour invasion and metastasis. A synthetic decapeptide designated αP2 containing two RGD sequences radiolabelled with technetium-99m was used to image malignant melanoma in vivo. Fourteen patients previously diagnosed with metastatic melanoma underwent gamma camera imaging 20-180 min following intravenous administration of the radiolabelled synthetic decapeptide αP2. Six out of eight (6/8) of the lymph node metastases (75%) and all other neoplastic sites (11 sites) were successfully imaged, with the exception of three sites in the mediastinal area which were not positively imaged. In two cases there was false positive uptake in the rounded pigmented areolar/nipple area. In three cases (seven sites) the peptide scan confirmed the absence of disease in suspected lesions (true-negative). The synthetic peptide was rapidly removed from the circulation by filtration through the kidneys and excretion in the urine. No toxicity or adverse events were recorded. Radiolabelled αP2 peptide, which binds specifically to adhesion molecules on tumours, can be used for the in vivo detection of neoplastic metastases. (orig.)

  5. Technetium-99m labeled antisense probes uptake in vascular smooth muscle cells

    In the arterial wall, smooth muscle cells (SMC) normally exist in a quiescent, differentiated state, representing the contractile phenotype. During the development of atherosclerosis SMC change towards the synthetic phenotype going along with proliferation, chemotactic response and increased monocyte binding. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. The atherosclerotic plaques contained 3-4 fold more c-myc mRNA than those in the normal aortic arteries, while increased Bax and Bak coupled with lack/paucity of Bcl-2 and Bcl-xL are associated with SMC apoptosis in advanced lesions. Methods: 1 Oligonucleotide Conjugation: A solution of single stranded amine-derivatized DNA (100-1000μg) was prepared at a concentration of 2 mg/ml in 0.25M sodium bicarbonate, 1 M sodium chloride, 1mM EDTA, pH8.5. Cell uptake studies: 99mTc- MAG3-DNA radioactivity incorporation into porcine coronary smooth muscle cells in the log and plateau phases, respectively, was determined after different times of incubation at 37. The influence of extracellular 99mTc- MAG3-DNA concentration on SMC uptake was also analyzed. [Results] Essentially complete conjugation was achieved by reverse-phase Sep-Pak C18 chromatography analysis. The MAG3-DNA was labeled with 99mTc at room temperature and neutral pH, with a mean labeling efficiency of 80.11%(s.d=2.96%,n=4). The labeled antisense DNA still remained the ability to hybridize with its complementary DNA. After labeling, the stability of the DNA in saline or serum was retained as determined by reverse-phase Sep-Pak C18 chromatography analysis, except a shift at 30 min in serum incubation that suggesting a short time serum protein binding. 99mTc-MAG3-c-myc uptake plateaued at 60 min and was directly proportional to the ex

  6. Contribution of technetium-99m hexamethylpropylene amine oxime labelled leucocyte scintigraphy to the diagnosis of diabetic foot infection

    We conducted a prospective study in order to evaluate the contribution of technetium-99m hexamethylpropylene amine oxime (HMPAO) labelled leucocyte scintigraphy to the diagnosis and follow-up of osteomyelitis in the diabetic foot. The study was conducted between October 1992 and November 1996 and included 42 patients (30 men and 12 women; mean age 63 years) with diabetes mellitus (type 1, n = 22, type 2, n = 20) who had a total of 56 diabetic foot ulcers. The initial exploration included standard radiography, three-phase bone scintigraphy and 99mTc-HMPAO labelled leucocyte scintigraphy (HMPAO-LS), performed within a 3-day interval. For the 56 ulceration sites, 26 cases of osteomyelitis were diagnosed: ten on the basis of radiographic and histological/bacteriological criteria after bone biopsy, 11 after radiographic follow-up and five on the basis of biopsy results alone. No osteomyelitis was present at 30 sites, there were seven cases of cellulitis. The sensitivity and specificity of 99mTc-HMPAO-LS were 88.4% and 96.6% respectively (23 true-positives, 29 true-negatives, one false-positive, three false-negatives). The accuracy of radiography, 99mTc-methylene diphosphonate and HMPAO-LS was 69.6%, 62.5%, and 92.9%, respectively. Follow-up scintigraphy (n = 14) 4 months after initial diagnosis and 1 month after antibiotic withdrawal confirmed cure of osteomyelitis despite the absence of complete clinical regression of the ulcers. In conclusion, 99mTc-HMPAO labelled leucocyte scintigraphy was found to be an excellent method for the diagnosis of osteomyelitis in the diabetic foot. It can contribute to follow-up, particularly when clinical regression of perforating ulcers is incomplete and cure of osteomyelitis must be confirmed in order that antibiotic treatment may be discontinued. (orig.)

  7. Contribution of technetium-99m hexamethylpropylene amine oxime labelled leucocyte scintigraphy to the diagnosis of diabetic foot infection

    Devillers, A.; Moisan, A.; Garin, E.; Bourguet, P. [CRLCC Eugene Marquis, Service de Medecine Nucleaire, Rennes (France); Hennion, F.; Poirier, J.Y. [CHRU Pontchaillou, Service d`Endocrinologie, Rennes (France)

    1998-02-01

    We conducted a prospective study in order to evaluate the contribution of technetium-99m hexamethylpropylene amine oxime (HMPAO) labelled leucocyte scintigraphy to the diagnosis and follow-up of osteomyelitis in the diabetic foot. The study was conducted between October 1992 and November 1996 and included 42 patients (30 men and 12 women; mean age 63 years) with diabetes mellitus (type 1, n = 22, type 2, n = 20) who had a total of 56 diabetic foot ulcers. The initial exploration included standard radiography, three-phase bone scintigraphy and {sup 99m}Tc-HMPAO labelled leucocyte scintigraphy (HMPAO-LS), performed within a 3-day interval. For the 56 ulceration sites, 26 cases of osteomyelitis were diagnosed: ten on the basis of radiographic and histological/bacteriological criteria after bone biopsy, 11 after radiographic follow-up and five on the basis of biopsy results alone. No osteomyelitis was present at 30 sites, there were seven cases of cellulitis. The sensitivity and specificity of {sup 99m}Tc-HMPAO-LS were 88.4% and 96.6% respectively (23 true-positives, 29 true-negatives, one false-positive, three false-negatives). The accuracy of radiography, {sup 99m}Tc-methylene diphosphonate and HMPAO-LS was 69.6%, 62.5%, and 92.9%, respectively. Follow-up scintigraphy (n = 14) 4 months after initial diagnosis and 1 month after antibiotic withdrawal confirmed cure of osteomyelitis despite the absence of complete clinical regression of the ulcers. In conclusion, {sup 99m}Tc-HMPAO labelled leucocyte scintigraphy was found to be an excellent method for the diagnosis of osteomyelitis in the diabetic foot. It can contribute to follow-up, particularly when clinical regression of perforating ulcers is incomplete and cure of osteomyelitis must be confirmed in order that antibiotic treatment may be discontinued. (orig.) With 5 figs., 3 tabs., 28 refs.

  8. Labeling of thymidine analog with an organometallic complex of technetium-99m for diagnostic of cancer: radiochemical and biological evaluation

    Thymidine analogs have been labeled with different radioisotopes due to their potential in monitoring the uncontrollable cell proliferation. Considering that the radioisotopes technetium-99m still keep a privileged position as a marker due to its chemical and nuclear properties, this dissertation was constituted by the developed of a new technique of labeling of thymidine analog with 99mTc, by means of the organometallic complex. The aims of this research were: synthesis of the organometallic complex technetium-99m-carbonyl, thymidine labeling with this precursor, evaluation of stability, and radiochemical e biological evaluation with healthy and tumor-bearing animals. The preparation of the organometallic precursor, using the CO gas, was easily achieved, as well as the labeling of thymidine with this precursor, resulting itself a radiochemical pureness of ≥ 97% and ≥ 94%, respectively. Chromatography systems with good levels of trustworthiness were used, ensuring the qualification and quantification of the radiochemical samples. The result of in vitro testing of lipophilicity disclosed that the radiolabeled complex is hydrophilic, with a partition coefficient (log P) of -1.48. The precursor complex and the radiolabeled have good radiochemical stability up to 6 h in room temperature. The cysteine and histidine challenge indicated losses between 8 and 1 1 % for concentrations until 300 mM. The biodistribution assay in healthy mice revealed rapid blood clearance and low uptake by general organs with renal and hepatobiliary excretion. The tumor concentration was low with values of 0.28 and 0.18 %ID/g for lung and breast cancer, respectively. The results imply more studies in other tumor models or the modification of the structure of the organic molecule that act like ligand. (author)

  9. Technetium-99m Labeled Somatostatin Analogues and their Role in the Management of Patients with Neuroendocrine Tumors

    Full text: The imaging of neuroendocrine tumors has become one of the most significant areas in nuclear oncology. In-111 DTP A-octreotide (Octreoscan (registered) , Mallinckrodt Medical, The Netherlands) is generally used for somatostatin receptor scintigraphy (SRS) for determining the presence of somatostatin receptors subtype 2 and 5 in NETs. In an attempt to provide high-quality imaging and possible sensitivity at reduced cost, time, and radiation doses, several Tc-99m agents have been proposed (1,2). Among them Tc-99m HYNIC-Tyr3-octreotide (Tc-99m HYNIC-TOC), has been for the first time granted marketing authorization and made available for the wide use (Tc-99m Tektrotyd, POLA TOM, Poland). The other analogue, Tc-99m HYNIC-Tyr3-octreotate (Tc-99m HYNIC-TATE), which chemically differs from Tc-99m HYNIC-TOC only with terminal amino acid in the peptide sequence (threonine replaces threoniol) in vitro presented higher receptor binding and better internalization (1). The diagnostic efficiency of both radiopharmaceuticals has been assessed in many clinical trials (3-8), mostly focused on the SRS in detection and staging of patients with neurondocrine gastro-entero-pancreatic tumors. Although both technetium-99m labeled analogues are in clinical use for a few years, they are already recognized as classical radiopharmaceuticals, with diagnostic utility superior to In-111 DTP A-Octreoscan. Both Tc-99m HYNIC-TOC and Tc-99m HYNIC-TATE, with high imaging quality, were shown to be excellent alternative to Tc-99m Octreoscan for staging of carcinoids, and they seem to be the method of choice for detection of the primary focus in patients with metastases from unknown primary tumor (4,7). With one-day, dual-time acquisition protocol the SRS was found to be an accurate staging procedure. The sensitivity of SRS in comparison with CT was higher for primary lesions and liver and abdominal lymph node metastases. SRS has substantially changed the management of the GEP-NET patients

  10. Preparation and biodistribution study of technetium-99m-labeled quercetin as a potential radical scavenging agent

    Free radicals and oxidative stress are the primary causes of several chronic diseases such as cancer and heart disease. Quercetin is a natural compound with potent antioxidant activity. We have prepared and evaluated technetium-99m (99mTc)-labeled quercetin as a potential radical scavenging radiotracer. A 99mTc-quercetin complex was prepared using quercetin, SnCl2 and Na99mTcO4 in a buffered solution over 30 min. The participation coefficient was measured in octanol and queues solutions. The stability was determined in phosphate buffered saline and serum. The biodistribution in normal mice was evaluated at 0.5, 2, 6 and 24 h post-injection. The radiochemical purity (>99%) was determined by thin layer chromatography (TLC) in normal saline solution as the mobile phase. It has a log P of 0.204. It was mainly cleared by the kidneys and showed negligible brain uptake at four time points measured post-injection. The pharmacological properties of quercetin, mainly its free radical scavenging, may potentially cat as a radiopharmaceutical agent for radical-targeted imaging of tissue with high levels of reactive oxygen species. (author)

  11. Synthesis and study of the biodistribution of a new molecule labeled by technetium 99M

    Cytectrenes are stable complexes, neutral, low-weight molecular and lipophilic, that's allowing them to be able to cross the intact BBB. These piperidinic molecules are synthesized by atomic exchange between tricarbonyl technetium with the Fe-Cyclopentadienyl fragment. The labelling reaction is carried out classically in oil bath at a temperature of 150 C during one hour. The reaction can be optimized using microwave. The study of the biodistribution in rat of these complexes after there purification shows high cerebral uptake. Cytectrenes can be used as a potential cerebral radiotracers for the early diagnosis of neuropsychiatric diseases. Cytectrene are able to cross the BBB regarding there lipophilicity. These characteristic allow them to cross the membrane of the white cells and to be used us a potential agent for the diagnosis of infection. (Author). 44 refs

  12. Discussion on twenty-two hepatobiliary scintigraphs performed with technetium 99m-labelled N-(2,6 dimethylphenylcarbamoylmethyl) iminodiacetic acid (or HIDA-99mTc) at the Val-de-Grace Army Instruction Hospital

    Intraveinously injected technetium 99m-labelled N-(2,6 dimethyl-phenylcarbamoylmethyl) iminodiacetic acid, or HIDA-99mTc, is taken up by the hepatocytes and secreted in the bile, a fraction being normally eliminated by the kidneys. Isotopic examination with HIDA-99mTc gives valuable information on the morphology of the liver during the first minutes of the test, thus revealing the presence of parenchyma disease. In all observed cases of secondary hepatic localisations in particular the HIDA-99mTc images overlie those obtained with technetium colloids. By the examination it is also possible: - to establish the existence or otherwise of a functional vesicle, - to follow the path of the radiotracer along the bile duct. In short, HIDA-99mTc hepatobiliary scintigraphy is particularly useful for the study of hepatocyte uptake and bile elimination since it allows a continuous quantitative study of the liver-bile function under given physiological conditions

  13. Use of a 99m technetium labeled glycolipopeptide encapsulated in liposomes for imaging of human tumors

    The potential use of immunomodulators from bacterial origin for the therapy of tumors in animal models as well as in humans has led to the isolation of several active fractions. The aim of our research was to study the possibility of tumor imaging, via certain activated cell types, after the administration of a radiolabeled glycolipopeptide isolated from Nocardia Opaca. The N.S.P.D. fraction (Nocardia Soluble Peptidoglycan), mitogen for B cells and macrophage activator, was labeled with sup(99m)Tc, encapsulated into liposomes and administered to patients through pulmonary way as aerosol. The scintigraphic exploration of 25 patients bearing tumors, mainly malignant melanoma, led us to detect some small tumor localisation (0.5 cm) that were not revealed using conventional tests. The results obtained in other tumors than melanomas show that tracer uptake is not specific for a given type of tumor and some experimental arguments are in agreement with the fact that macrophages present in the tumors could play an important role in tracer uptake. As far as this method involves the indirect labeling of a cellular type specifically associated to the tumor proliferation it could provide a new and original approach for oncologic scintigraphy. (Author)

  14. Technetium-99m ceftizoxime kit preparation

    The aim of this work was to prepare a kit of 99m Tc-ceftizoxime (99m Tc-CFT), with stability and biological activity preserved, able to identify a septic focus (E. coli) in the experimental infection model in rats. The preparation of the CFT kit involved the use of lyophilized solutions containing the antibiotic ceftizoxime and the sodium dithionite reducing agent (6.0 mg/m L). After lyophilization, the kit was reconstituted with 1.0 mL of sodium 99m Tc pertechnetate solution (Na 99m Tc O4-) with an activity of 370 MBq. The solution was boiled for 10 min and filtered through a cellulose ester filter. The labeling efficiency was on the order of 92%, remaining stable for six hours and the kit remained stable for two months. The biological activity of the 99m Tc-CFT was evaluated by diffusion in agar impregnated with E.coli and S. aureus. Seven Wistar rats, weighing from 200 to 250 g, were used for the development of the septic focus. After 24 hours from the induction of the infectious site (E.coli), the animals were anesthetized and 0.1 mL of 99m Tc-CFT (37 MBq) was injected into the tail veins of the animals. The images were obtained with a gamma camera one, two and six hours after injection and the regions of interest (ROIs) were calculated. The diameters of the inhibition halos for 99m Tc-CFT were 27.16 ± 0.23 and 27.17 ± 0.20 for S.aureus and E.coli, respectively, while those for the unlabeled CFT were 30.4 ± 0.33 and 29.43 ± 0.26, respectively. The results for the biodistribution of 99m Tc-CFT in infected animals furnished a ratio of 1.97 ± 0.31, 2.10 ± 0.42 and 2.01 ± 0.42 for cpm-target/cpm-no target for the one, two and six-hour periods, respectively. The images showed a clear uptake of labeled antibiotic (99m Tc-CFT) by the infectious site during the experiment. The results attest to the viability of producing a kit with 99m technetium-labeled ceftizoxime for the investigation of infectious processes. (author)

  15. Clinical evaluation of technetium-99m labeled red blood cell scan in the detection of gastrointestinal hemorrhage

    A three years' experience at Chigasaki Tokushukai Medical Center with Technetium-99m labeled red blood cell scintiscans (Tc-99m-RBC Scan) performed on 68 cases of suspected lower gastrointestinal (LGI) bleeding was reviewed in retrospect. Of the 36 cases performed within 24 hours from the clinical detection of active LGI hemorrhage on emergency basis, 27 cases were positive (75 % positivity). Of the total 45 positive cases, 21 (47 %) became positive one or more hours post injection, confirming the intermittent nature of the LGI hemorrhage. All studies were completed without untoward effects and confirmed the noninvasive nature of the study, as compared to the other invasive modalities such as endoscopy and angiography. Detection and localization of the site of LGI bleeding directed the precise modality to be chosen subsequently and greatly facilitated in performing the invasive procedure with selectivity further improving its sensitivity. Tc-99m-RBC scan is a completely noninvasive, simple and sensitive procedure, which may be used initially in routine to detect and localize LGI bleeding. (author)

  16. Morphologic alterations on red blood cells labeled with technetium-99m: the effect of Mentha crispa L. (hortela) extract

    The use of natural products, as medicinal plants, is very frequent in the world. Mentha crispa L. (M. crispa) is utilized in herbal medicine. Blood elements labeled with technetium-99m (99mTc) are used in nuclear medicine procedures and this labeling process may be altered by drugs. We have investigated the possibility of M. crispa extract being capable to alter the labeling of blood elements with 99mTc. Blood was incubated with M. crispa extract in various concentrations (6.25, 12.5, 25, 50 and 100%). Stannous chloride solution and Tc-99m, as sodium pertechnetate, were added. Blood was centrifuged and plasma (P) and blood cells (BC) were isolated. Samples of P and BC were also precipitated, centrifuged and insoluble (IF) and soluble (SF) separated. The percentage of radioactivity (%ATI) in BC, IF-P and IF-BC was calculated. Histological evaluations of the red blood cells (RBC) were performed with blood samples treated with various concentrations of M. Crispa L. and the morphology of the RBC was observed under optical microscope. Important morphological alterations expressed by mean of the perimeter/area of the RBC treated with M. crispa: 6.25% (0.67 ± 0.02), 12.5% (0.77 ± 0.03), 25% (0.73 ± 0.04), 50% (0.76 ± 0.04), 100% (0.69 ± 0.08) and the control cells (0.67 ± 0.05). The %ATI decreased: (i) on BC from 97.3 ± 1.92 to 60.0 ± 2.44; (ii) on IF-P from 74.8 ± 3.78 to 9.99 ± 3.61; (iii) on IF-BC from 88.6 ± 5.41 to 58.4 ± 11.55. The perimeter/area of the RBC showed significant differences (P>0.01) when compared 6.25% and 12.5%, and when compared 6.25% and 50% of M. Crispa L. extract. These findings could also justify the decrease of the labeling of BC with 99mTc in presence of M. Crispa extract

  17. Detection of homing-in of stem cells labeled with technetium-99m hexamethylpropyleneamine oxime in infarcted myocardium after intracoronary injection

    Bone marrow stem cells having myogenic potential are promising candidates for various cell-based therapies for myocardial disease. We present here images showing homing of technetium-99m (Tc-99m) hexamethylpropyleneamine oxime (HMPAO) labeled stem cells in the infarcted myocardium from a pilot study conducted to radio-label part of the stem cells in patients enrolled in a stem cell clinical trial for recent myocardial infarction

  18. Chronic complicated osteomyelitis of the appendicular skeleton: diagnosis with technetium-99m labelled monoclonal antigranulocyte antibody-immunoscintigraphy

    Chronic post-traumatic osteomyelitis (OM) represents a particular challenge for nuclear medicine and radiology since clinical and biochemical parameters are frequently unreliable. The aim of this study was to investigate the value of combined bone scan (BS) and immunoscintigraphy (IS) with technetium-99m labelled monoclonal antigranulocyte antibody (MAB) in patients with suspected chronic OM of the appendicular skeleton. Twenty-four patients (17 females and 7 males) with suspected chronic post-traumatic OM were evaluated with three-phase BS/99mTc-MAB-IS. The final diagnosis was established by means of bone culture and histology in 19 cases and clinical follow-up in five cases. The studies were reviewed by two independent and experienced observers; the interobserver agreement was calculated by kappa statistics. The sensitivity, specificity and accuracy of BS alone were 92%, 18% and 58%, respectively. Combined BS/99mTc-MAB-IS had a sensitivity, specificity and accuracy of 84%, 72% and 79%, respectively. Of 24 studies, 11 were true-positive, two false-negative, eight true-negative and three false-positive. Two patients presented with unexpected ectopic haematopoietic bone marrow in the appendicular skeleton that caused false-positive results. A high degree of interobserver agreement was found (κ=0.85). It is concluded that combined BS/99mTc-MAB-IS represents a very sensitive and reproducible method with an acceptable specificity for the investigation of chronic OM. Problems may occur in the differentiation of low-grade OM from aseptic inflammation. Another problem is ectopic marrow that may occur in the appendicular skeleton due to a chronic inflammatory stimulus. A former intramedullary intervention in the femur with displacement of haematopoietic marrow may also lead to an ectopic location. (orig.). With 2 figs., 1 tab

  19. Conversion to Paradoxical Finding on Technetium-99m-labeled RBC Scintigraphy after Treatment for Secondary Raynaud's Phenomenon

    An 18-year-old woman reported that after exposure to cold temperatures her fingers appeared blue and her hands and feet felt cold. Secondary Raynaud's phenomenon (RP) associated with peripheral vascular disease was suspected. Technetium (Tc)-99m-labeled RBC hand scintigraphy after cold change showed decreased blood pool activity in her fingers. The patient's symptoms improved after she received sarpogrelate HCL (200 mg/day) and nifedifine (40 mg/day). Follow-up scintigraphy performed 7 months after the patient started treatment showed paradoxically increased blood pool activity in her fingers after cold challenge. To the best of our knowledge, this is the first case report of a patient with secondary RP showing paradoxical change on scintigraphy after she received medication that improved her symptoms

  20. Detection of acute gastrointestinal bleeding by means of technetium-99m in vivo labelled red blood cells

    Prognosis of gastrointestinal (GI) bleeding depends on the timely and accurate detection of the source of bleeding and sequential surgical or endoscopy therapy. Scintigraphy with red blood cells (RBCs) in vivo labelled by means of technetium-99m hastened detection of source of GI bleeding and improved management of the particular disease. Gastrointestinal endoscopy is the method of choice for the diagnostics of bleeding from upper tract and large bowel. For diagnostics of bleeding from the small bowel we can use scintigraphy with in vivo labelled autological red blood cells if pushenteroscopy, intra-operative enteroscopy or angiography are not available. 31 patients (13 men, 18 women, aged 20-91, mean 56 years) underwent this investigation from 1998 till 2001 at the Department of Nuclear Medicine. All patients had melaena or enterorrhagia associated with acute anaemia. Gastroscopy, colonoscopy, enteroclysis or X-ray angiography did not detect the source of bleeding. Twenty-one patients had positive scintigraphy with in vivo labelled RBCs - 9 patients were already positive on dynamic scintigraphy, and 12 patients were positive on static images. Scintigraphy with in vivo labelled RBCs was negative in 10 patients. GI bleeding stopped spontaneously in these 10 patients with negative scintigraphy. These patients did not undergo intra-operative enteroscopy or surgery. The final diagnosis of the 21 patients with positive scintigraphy was determined in 16 patients by push-enteroscopy (6 patients), intra-operative enteroscopy (6 patients) or by surgery (4 patients). Of these 16 patients the correct place of bleeding was determined by scintigraphy with labelled RBCs in 11 (69%) patients. Final diagnoses of our 16 patients with positive scintigraphy with autological labelled RBCs were: bleeding small bowel arteriovenous malformation (6 patients), uraemic enteritis with bleeding erosions in ileum and jejunum (2 patients), Osler-Rendu- Weber disease (1 patient), pseudocyst of

  1. Study of factors that interfere in the labelling process of erythrocytes and plasma proteins with Technetium-99m; Estudo de fatores que interferem no processo de marcacao de hemacias e proteinas plasmaticas com tecnecio-99m

    Gutfilen, Bianca

    1989-12-31

    The labelling of red blood cells (RBC) with technetium-99m (Tc-99m) depends on several factors, as the stannous ion (Sn++) concentration, time, temperature, the presence of plasma proteins (PP) and others. However the Sn++ concentration seems to be the most important factor; probably because the uptake of this reducing agent by RBC is limited. The excess of Sn++ in extracellular medium can determine the labelling of PP. the modifications of RBC at 50 deg C described in the literature, the possibility of labelling RBC with Tc-99m at this temperature and experimental results obtained made it possible to perform spleen selective scintigraphy through a simple technique with few manipulations. The effect of gentamicin, nifedipine and verapamil in the labelling of RBC and plasma proteins with Tc-99m was studied because of similarities between Ca++ and Sn++. The results show that, under some conditions, these drugs are capable to alter this Tc-99m incorporation. The modification of the ionic distribution determined by these drugs or the blockage of Sn++ and/or Tc-99m or the fact that they bind theirselves to plasma proteins, or the possibility of the labelling of these drugs, are factors that can interfere in the labelling process of red blood cells and plasma proteins with Tc-99m. (author) 55 refs., 12 figs., 5 tabs.

  2. Effects of chronic sucralose sweetener on the labeling of blood constituents with technetium-99m, morphology of red blood cells and the biodistribution of sodium pertechnetate in rats

    Gabrielle de Souza Rocha; Marcia de Oliveira Pereira; Mônica Oliveira Benarroz; Jacques Natan Grinapel Frydman; Angélica Beatriz Garcia-Pinto; Mário José Pereira; Adenilson de Souza da Fonseca; Mario Bernardo-Filho

    2008-01-01

    This work evaluates effects of the sweetener with sucralose on the labeling of blood constituents with technetium-99m (99mTc), on the morphology of red blood cells (RBC) and on the biodistribution of sodium pertechnetate in Wistar rats. Animals were treated with sweetener for 8 days. Blood samples were withdrawn and the assay of labeling of blood constituents with 99mTc was performed. Blood cells (BC) and plasma (P) were isolated. Aliquots of BC and P were also precipitated, soluble and insol...

  3. Effect of an Arctium lappa (burdock) extract on the labeling of blood constituents with technetium-99m and on the morphology of the red blood cells

    Rosane de Figueiredo Neves; Silvana Ramos Farias Moreno; Bernardo Machado Rebello; Luiz Querino de Araújo Caldas; Adenilson de Souza da Fonseca; Mario Bernardo-Filho; Aldo da Cunha Medeiros

    2007-01-01

    Arctium lappa (burdock) has been used to treat inflammatory processes. Blood constituents labeled with technetium-99m (99mTc) have been utilized in nuclear medicine. It was evaluated the influence of a burdock extract on the labeling of blood constituents with 99mTc and on the morphometry of red blood cells. Blood samples from Wistar rats were incubated with burdock extract and the radiolabeling procedure was carried out. Plasma and blood cells, soluble and insoluble fractions of plasma and b...

  4. Preparation and evaluation of technetium-99m labeled cardiac glycoside derivatives as potential myocardial imaging agent

    Misra, Mridula; Sarkar, H.S.; Chatterjee, Mita; Banerjee, Somenath

    1988-01-01

    Three cardiac glycosides, two natural, cymarin and convallotoxin and one synthetic, strophanthidin-..beta..-D-glucoside were converted to their thiosemicarbazone and subsequently radiolabeled with sup(99m)Tc by chelation. The resulting radioactive chelate complexes were evaluated in animals to determine the suitability of this class of compounds for myocardial imaging. It was observed from the animal biodistribution data of the three radioactive compounds that there was a considerable variation in the heart to non-target organ uptake ratio. A possible explanation of this variation was offered in the light of their lipophilic character, protein binding ability and affinity towards non-target receptors. It is anticipated that this study may help to develop a sup(99m)Tc-cardiac glycoside complex with better distribution characteristics, and such a compound may offer a suitable alternative to /sup 201/Tl, which is at present used for myocardial imaging.

  5. Demonstration of hematobilia using technetium-99m labeled red blood cells

    Lee, S.M.; Lee, R.G.; Clouse, M.E.; Hill, T.C.

    1986-01-01

    A 75-year-old woman, who presented with obstructive jaundice, was shown by percutaneous transhepatic cholangiography to have a markedly dilated biliary system and stones within the common bile duct. The stones were removed percutaneously using the transduodenal approach, and an internal drainage catheter was placed. Following the procedure, the patient experienced gastrointestinal bleeding manifested by melanotic stools. Blood-tinged bile was withdrawn from the biliary drainage catheter, leading to the suspicion that the bleeding might be originating from the biliary tract. A Tc-99m red blood cell (Tc-99m RBC) scan was performed to try to designate the biliary tract as the site of bleeding, and to determine if there were any other bleeding sites present. The study demonstrated bleeding from the biliary tract, which was confirmed by angiography and endoscopy. The technique for the detection of gastrointestinal bleeding using Tc-99m RBCs is well described. This case suggests that when doing studies to localize occult bleeding, the liver should be included in the field-of-view to exclude bleeding from the liver.

  6. Drug interaction with radiopharmaceuticals: effect on the labeling of red blood cells with technetium-99m and on the bioavailability of radiopharmaceuticals

    Gomes Maria Luisa; Oliveira Marcia B. Nunes de; Bernardo-Filho Mario

    2002-01-01

    The evidence that natural and synthetic drugs can affect radiolabeling or bioavailability of radiopharmaceuticals in setting of nuclear medicine clinic is already known. However, this drug interaction with radiopharmaceuticals (DIR) is not completely understood. Several authors have described the effect of drugs on the labeling of blood elements with technetium-99m (99mTc) and on the biodistribution of radiopharmaceuticals. When the DIR is known, if desirable or undesirable, the natural conse...

  7. Technetium-99m labelled macroaggregated albumin arterial catheter perfusion scintigraphy: prediction of gastrointestinal toxicity in hepatic arterial chemotherapy.

    Pelosi, E; Masaneo, I; Clara, R; Valetto, M R; Bellò, M; Zanon, C; Chiappino, I; Grosso, M; Mussa, A; Bisi, G

    2000-06-01

    Gastrointestinal toxicity from hepatic arterial infusion (HAI) of floxuridine in patients with liver metastases is probably due to extrahepatic perfusion or to partial escape of the drug from first-pass liver extraction. The aim of this study was to verify the role of technetium-99m-labelled macroaggregated albumin (99mTc-MAA) arterial catheter perfusion scintigraphy at the beginning of each chemotherapy cycle in decreasing or preventing gastrointestinal toxicity. We studied 167 consecutive patients. On the basis of the scintigraphic follow-up and the presence or absence of an intrahepatic arteriovenous shunt (IHAVS), we classified our patients into the following groups: (1) FU+ hepatic distribution pattern (DP), comprising 29 patients with regular scintigraphic follow-up who showed the expected distribution pattern at each control or a distribution pattern with transient alterations (extrahepatic escape) promptly reversed by the replacement of the catheter. Among these 29 patients there was one case of gastrointestinal toxicity. (2) FU- hepatic DP, comprising 128 patients who were evaluated with 99mTc-MAA only at the beginning of the first chemotherapy cycle, showed the expected distribution pattern and underwent HAI with no further scintigraphic evaluation. Among these 128 patients there were 28 cases of gastrointestinal toxicity. (3) FU+ pulmonary DP, comprising three patients with abnormally elevated pulmonary uptake (higher than 5%) and with regular scintigraphic follow-up. There were two cases of gastrointestinal toxicity among these three patients. (4) FU- pulmonary DP, comprising seven patients with abnormally elevated pulmonary uptake and without regular scintigraphic follow-up. There were four cases of gastrointestinal toxicity among these seven patients. The incidence of toxicity was significantly higher in group FU- hepatic DP than in group FU+ hepatic DP (21.9% vs 3.4%, Pscintigraphic follow-up is useful since it is able to promptly diagnose the

  8. Distribution of injected technetium(99m)-labeled mesenchymal stem cells in horses with naturally occurring tendinopathy.

    Becerra, Patricia; Valdés Vázquez, Miguel A; Dudhia, Jayesh; Fiske-Jackson, Andrew R; Neves, Francisco; Hartman, Neil G; Smith, Roger K W

    2013-07-01

    This study aimed to investigate immediate cell survival and distribution following different administration routes of mesenchymal stem cells (MSCs) into naturally occurring tendon injuries. Ten million MSCs, labeled with technetium-99m hexamethylpropyleneamine oxime, were implanted into 13 horses with naturally occurring tendon or ligament injuries intra-lesionally, intravenously and by regional perfusion, and traced for up to 48 h using planar gamma scintigraphy. Labeling efficiencies varied between 1.8% and 18.5% (mean 9.3%). Cells were retained in the damaged area after intra-lesional administration but only 24% of cells were still present within the tendon after 24 h. After intravenous injection, cells largely distributed to the lung fields, with no detectable cells in the tendon lesions. Significant labeling of the tendon lesions was observed in 11/12 horses following regional perfusion but at a lower level to intra-lesional injection. The highest cell numbers were retained after intra-lesional injection, although with considerable cell loss, while regional perfusion may be a viable alternative for MSC delivery. Cells did not "home" to damaged tendon in large numbers after intravenous administration. Cells were detected in the lungs most frequently after intravascular administration, although with no adverse effects. Low cell retention has important implications for designing effective clinical therapies for human clinical use. PMID:23508674

  9. Development of nano radiopharmaceutical based on Bevacizumab labelled with Technetium-99m for early diagnosis of gastrointestinal stromal tumor

    The development of new radiopharmaceuticals is an essential activity to improve nuclear medicine, and essential for the early and effective diagnosis of oncological diseases. Among the various possibilities current research in the world, the radiopharmaceuticals to chemotherapeutic base may be the most effective in detecting tumors, particularly Gastrointestinal Stromal Tumor (GIST), the Metastatic Renal Cell Carcinoma and neuroendocrine pancreatic tumors. However, difficulties in directing, as well as adhesion of the radiopharmaceutical in the desired location, are currently the main problems in the early detection and treatment of some of these tumors. Advances in the field of nanotechnology, particularly in recent years, indicate significant contribution to overcoming these obstacles, particularly in the implementation of molecular barriers as well as the functionalization of the nanoparticles, thereby improving targeting by the use of surface nucleotides, and the increased adhesion, which facilitates the release of the drug and therefore increases the chances of early diagnosis and more effective treatment. This study aimed to the production, characterization and evaluation of cytotoxicity, as well as in vivo biodistribution test Bevacizumab nanoparticles labeled with Technetium-99m radionuclide for detection of type GIST tumors. Bevacizumab was encapsulated in the form of nanoparticles by the emulsification method using double poly-acetic acid and polyvinyl alcohol polymers (PLA / PVA) at a concentration of 2% of the monoclonal antibody. The characterization of the nanoparticles was performed by the technique of scanning electron microscopy (SEM). The cytotoxicity assessment was performed by XTT assay with various cell lines of solid tumor cells. The labeling with technetium-99m was done by the direct method, and its yield determined by paper chromatography using paper Whatmam 1 as the stationary phase and acetone as mobile phase. In the biodistribution study

  10. The quality control of technetium-99m radiopharmaceuticals produced at the AAEC Research Establishment

    The methods of quality control used for technetium-99m radiopharmaceuticals produced at the AAEC Research Establishment are described for both non-fission and fission derived sources of sodium pertechnetate, technetium-99m labelled radipopharmaceuticals, and reagent kits produced for technetium-99m labelling

  11. Technetium-99m labeling of tityustoxin and venom from the scorpion Tityus serrulatus

    Nunan, E.A.; Cardoso, V.N.; Moraes-Santos, T. E-mail: tmoraes@dedalus.lcc.ufmg.br

    2002-12-01

    The tityustoxin, the most toxic fraction from scorpion Tityus serrulatus venom, has been used as a tool in several neurochemical and neuropharmacological studies. Biological activities of labeled and unlabeled tityustoxin and venom were compared. The samples were labeled in the presence of stannous chloride and sodium borohydride with a yield of 60-70% for the venom and 75-85% for tityustoxin and then chromatographed in Sephadex G-10. Biological activities of tityustoxin and venom were preserved after labeling.

  12. Technetium-99m labeling of tityustoxin and venom from the scorpion Tityus serrulatus

    The tityustoxin, the most toxic fraction from scorpion Tityus serrulatus venom, has been used as a tool in several neurochemical and neuropharmacological studies. Biological activities of labeled and unlabeled tityustoxin and venom were compared. The samples were labeled in the presence of stannous chloride and sodium borohydride with a yield of 60-70% for the venom and 75-85% for tityustoxin and then chromatographed in Sephadex G-10. Biological activities of tityustoxin and venom were preserved after labeling

  13. Technetium-99m labelled macroaggregated albumin arterial catheter perfusion scintigraphy: prediction of gastrointestinal toxicity in hepatic arterial chemotherapy

    Pelosi, E.; Masaneo, I.; Valetto, M.R.; Bello, M.; Bisi, G. [Department of Nuclear Medicine, University of Turin, Turin (Italy); Clara, R.; Zanon, C.; Chiappino, I.; Mussa, A. [Division of Esophageal and Oncological Surgery, University of Turin, Turin (Italy); Grosso, M. [Division of Radiology, S. Croce e Carle Hospital, Cuneo (Italy)

    2000-06-01

    Gastrointestinal toxicity from hepatic arterial infusion (HAI) of floxuridine in patients with liver metastases is probably due to extrahepatic perfusion or to partial escape of the drug from first-pass liver extraction. The aim of this study was to verify the role of technetium-99m-labelled macroaggregated albumin ({sup 99m}Tc-MAA) arterial catheter perfusion scintigraphy at the beginning of each chemotherapy cycle in decreasing or preventing gastrointestinal toxicity. We studied 167 consecutive patients. On the basis of the scintigraphic follow-up and the presence or absence of an intrahepatic arteriovenous shunt (IHAVS), we classified our patients into the following groups: (1) FU+ hepatic distribution pattern (DP), comprising 29 patients with regular scintigraphic follow-up who showed the expected distribution pattern at each control or a distribution pattern with transient alterations (extrahepatic escape) promptly reversed by the replacement of the catheter. Among these 29 patients there was one case of gastrointestinal toxicity. (2) FU- hepatic DP, comprising 128 patients who were evaluated with {sup 99m}Tc-MAA only at the beginning of the first chemotherapy cycle, showed the expected distribution pattern and underwent HAI with no further scintigraphic evaluation. Among these 128 patients there were 28 cases of gastrointestinal toxicity. (3) FU+ pulmonary DP, comprising three patients with abnormally elevated pulmonary uptake (higher than 5%) and with regular scintigraphic follow-up. There were two cases of gastrointestinal toxicity among these three patients. (4) FU- pulmonary DP, comprising seven patients with abnormally elevated pulmonary uptake and without regular scintigraphic follow-up. There were four cases of gastrointestinal toxicity among these seven patients. The incidence of toxicity was significantly higher in group FU- hepatic DP than in group FU+ hepatic DP (21.9% vs 3.4%, P<0.05). In both the FU+ pulmonary DP and FU- pulmonary DP groups, the

  14. Recruitment of 99m-technetium- or 111-indium-labelled polymorphonuclear leucocytes in experimentally induced pyogranulomas in lambs

    The recruitment of polymorphonuclear leucocytes (PMNs) during the development of experimental pyogranulomas induced by Corynebacterium pseudotuberculosis was followed in nine male lambs by scintigraphic examination. Autologous blood PMNs were labelled with 99m-technetium or 111-indium and were re-injected intravenously into infected lambs. The functional properties of the labelled cells were monitored (1) in vitro by measuring their phagocytic and bactericidal activity against C. pseudotuberculosis and their chemotaxis under agarose, and (2) in vivo by following scintigraphically their capacity to accumulate in an inflammatory focus induced by intradermal injection of latex beads coated with Salmonella abortus equi lipopolysaccharide. Following inoculation of corynebacteria into the right ear of lambs, radioactive foci were observed to be localized in the right ear and in the draining lymph nodes during the 4 days following inoculation. Histopathological examination performed 32 h after inoculation confirmed the intense accumulation of PMNs at these sites. With the exception of one animal, which presented visible foci in the neck 14 days postinoculation, no radioactive foci were observed during the later phases of experimental infection, despite the presence of multiple pyogranulomas which were confirmed by bacteriological examination after necropsy of the lambs. Histopathological examination of these lesions revealed layers of fibroblasts, lymphocytes, and macrophages surrounding a necrotic centre. The results of these studies suggest that the contribution of PMNs during the chronic phase of inflammation is considerably reduced in comparison with the acute inflammatory phase of the infectious process

  15. Technetium-99m ceftizoxime kit preparation

    Simone Odília Fernandes Diniz

    2005-10-01

    Full Text Available The aim of this work was to prepare a kit of 99mTc-ceftizoxime (99mTc-CFT, with stability and biological activity preserved, able to identify a septic focus (E. coli in the experimental infection model in rats. The preparation of the CFT kit involved the use of lyophilized solutions containing the antibiotic ceftizoxime and the sodium dithionite reducing agent (6.0 mg/mL. After lyophilization, the kit was reconstituted with 1.0 mL of sodium 99mTc-pertechnetate solution (Na99mTcO4- with an activity of 370 MBq. The solution was boiled for 10 min and filtered through a cellulose ester filter. The labeling efficiency was on the order of 92%, remaining stable for six hours and the kit remained stable for two months. The biological activity of the 99mTc-CFT was evaluated by diffusion in agar impregnated with E.coli and S. aureus. Seven Wistar rats, weighing from 200 to 250 g, were used for the development of the septic focus. After 24 hours from the induction of the infectious site (E.coli, the animals were anesthetized and 0.1 mL of 99mTc-CFT (37 MBq was injected into the tail veins of the animals. The images were obtained with a gamma camera one, two and six hours after injection and the regions of interest (ROIs were calculated. The diameters of the inhibition halos for 99mTc-CFT were 27.16 ± 0.23 and 27.17 ± 0.20 for S.aureus and E.coli, respectively, while those for the unlabeled CFT were 30.4 ± 0.33 and 29.43 ± 0.26, respectively. The results for the biodistribution of 99mTc-CFT in infected animals furnished a ratio of 1.97 ± 0.31, 2.10 ± 0.42 and 2.01 ± 0.42 for cpm-target/cpm-no target for the one, two and six-hour periods, respectively. The images showed a clear uptake of labeled antibiotic (99mTc-CFT by the infectious site during the experiment. The results attest to the viability of producing a kit with 99m technetium-labeled ceftizoxime for the investigation of infectious processes.O objetivo deste trabalho foi preparar um kit de Tc

  16. Scintigraphic assessment of bowel involvement and disease activity in Crohn's disease using technetium 99m-hexamethyl propylene amine oxine as leukocyte label

    Using a novel labeling technique with technetium 99m-hexamethyl propylene amine oxine, we studied 29 patients with known or suspected Crohn's disease. Technetium 99m-hexamethyl propylene amine oxine leukocyte scanning (99mTc scan) was prospectively compared with the results of independently performed radiologic, endoscopic, and histologic examinations, and with findings at surgery, to assess the clinical usefulness of this technique to localize inflammatory lesions. In addition, uptake of technetium 99m-hexamethyl propylene amine oxine in the bowel was graded by comparing it with the uptake in liver and bone marrow and correlating this with established parameters of disease activity. The viability of homologous labeled leukocytes was greater than 95%. Less than 5% of lymphocytes were found in the final preparation. It was found that 45% +/- 12% of the label was bound to granulocytes, and 98% of the unbound label was washed off before reinjection. The results of 99mTc scan revealed a good correlation with those of barium enema (r = 0.880, p less than 0.001), of endoscopy/surgery (r = 0.983, p less than 0.001), and of all combined reference methods (r = 0.981, p less than 0.001). Activity as determined by 99mTc scan was weakly correlated with the results of Crohn's disease activity index (r = 0.559, p less than 0.01), van Hees index (r = 0.606, p less than 0.01), and erythrocyte sedimentation rate (r = 0.456, p less than 0.05) in 24 patients with proven Crohn's disease. The correlation was improved when the 99mTc scan was compared with a combination of these activity parameters and C-reactive protein (r = 0.781, p less than 0.001). Extraintestinal manifestations (joints) and complications (cholecystitis) were also identified correctly by the 99mTc scan

  17. Labelling of bleomycin with technetium-99m for diagnosis in nuclear medicine

    A study about the behavior of the labelling yield of an antineoplastic drug (bleomycin) with a short-leved radionuclide (99 sup(m) Tc), using An(II) as a reductor agent, is presented. Parameters like the pH in the labelling, influence of the reaction time and mass of tin on the labelling yield were analysed. To simplify the labelling,, a lyofilized kit of Sn(II)/BLM in evacuated vials was prepared. The quality control involving paper chromatography, sterility and 'in vivo' test was made. The 'in vivo' tests were made both in healthy rats and in those with tumorous tissues, under barbituric action. The biological distribution, the concentration time of the products in tumors, the excretion time and excretion via were studied by means of scintigraphy and scintiphotos. (Author)

  18. In-vivo labelling of renal calculi with technetium 99m methylene diphosphonate

    A method of labelling renal calculi in-vivo with 99Tcsup(m) methylene diphosphonate is described. The way in which this enables the stones to be located both before and during surgical removal is discussed. (author)

  19. Prognostic relevance of pancreatic uptake of technetium-99m labelled human polyclonal immunoglobulins in patients with type 1 diabetes

    Insulin-dependent type 1 diabetes (IDDM) is caused by the autoimmune destruction of insulin-producing beta cells. Approximately 10%-20% of patients may benefit from adjuvant immunotherapy upon diagnosis of the disease in order to protect residual beta-cell function. It has been suggested that this subgroup of patients differs from others by virtue of the presence of residual pancreatic inflammation and beta-cell function. In this study we have investigated to what extent technetium-99m-labelled human polyclonal immunoglobulins (99mTc-HIG) accumulate in the pancreas of IDDM patients at the time of diagnosis and 1 year thereafter, with a view to ascertaining whether HIG scintigraphy is useful for the identification of IDDM patients with residual pancreatic inflammation. Patients with recent-onset IDDM (n=15) were investigated at the time of diagnosis and 1 year later, and ten age- and sex-matched normal subjects were also studied. Gamma camera imaging and target to background ratio, analysed blind by three independent readers, were used to quantify the radioactivity in the pancreatic region and findings were correlated with metabolic, immunological and clinical parameters. Seven out of 15 newly diagnosed IDDM patients showed a significant accumulation of radiolabelled HIG in the pancreas (pancreas/bone ratio higher than the mean +2SD of normal subjects). One year after diagnosis, pancreatic accumulation of HIG was still detectable in most IDDM patients who were positive at the time of diagnosis. Six out of seven patients with positive scintigraphy had a partial clinical remission. These results indicate that HIG scintigraphy at the time of onset of diabetes identifies a subset of patients with residual beta-cell function who may benefit from adjuvant immunotherapy. (orig.)

  20. Technetium-99m HMPAO labelled-leukocytes and gallium-67 scintigraphies in a Munchhausen's syndrome

    We report an observation of investigations performed in a patient with several cervical abscesses in his previous history. Aim of scintigraphic examinations was to detect an evolutive infection and/or to identify a general disease like granulomatosis. Although there was no abnormality on the labelled-leucocytes scintigraphy, an infra-mandibular uptake was observed 10 days later on 67Ga, without bone involvement. This 'discrepancy' between scintigraphic results and the clinical evolution allowed to confirm its management in nuclear medicine were discussed. (author)

  1. Technetium-99m labelling of the ior-CEA-1 monoclonal antibody: Evaluation of different methods

    In the present work, we evaluated the influence of experimental conditions on the characteristics of the radiolabelled ior-CEA-1 prepared by direct method, using 2-ME and stannous chloride as reductants and indirect method in which 2-IM is used to generate sulfhydryl groups in the protein. The following parameters were studied: number of free sulfhydryl groups of treated antibody, labelling efficiency, chemical and radiochemical composition of the radiolabelled antibodies as well as their immunological and biological properties. The properties of 99Tcm-ior-CEA-1 obtained by 2-ME method were compared to the ones of the 99Tcm-monoclonal antibody obtained from a commercial kit (BW 431/26). Some clinical studies using 99Tcm-ior-CEA-1 were also performed

  2. Preparation and Biodistribution of Technetium-99m-Labeled Bis- Misonidazole (MISO) as an Imaging Agent for Tumour Hypoxia.

    Wang, Feng; Fan, Di; Qian, Jun; Zhang, Zhe; Zhu, Jianhua; Chen, Jian

    2015-01-01

    Diagnosis of tumour hypoxia is an important aspect in determining the course of tumour therapy. In this study, we developed a novel imaging agent, (99m)Tc-ethylenedicysteine-bis-misonidazole ((99m)Tc-EC-MISO), for diagnosing tumour hypoxia. We used 2-nitroimidazole as a reactant to synthesize the amino derivative of misonidazole (MISO) in the first step and then conjugated the di-amino derivative of MISO to the chelating agent ethylenedicysteine (EC) for labelling (99m)Tc in the second step. (99m)Tc-pertechnetate ((99m)TcO4-) was reduced by tin chloride (SnCl2) for radiolabeling. The radiochemical purity was up to 94%. Tissue biodistribution and SPECT/CT imaging studies were conducted on subcutaneous gliomal tumour-bearing mice. The tumour-to-muscle ratio in the (99m)Tc-EC-MISO group increased with time, up to 4.6 at 4 h after injection. SPECT/CT imaging confirmed that the tumours could be visualized clearly with (99m)Tc-EC-MISO at 2 h. By introducing a second 2-nitroimidazole redox centre, an apparent hypoxic accumulation of this novel (99m)Tc-labeled imaging agent in the tumour was observed. PMID:25938423

  3. Effect of an Arctium lappa (burdock) extract on the labeling of blood constituents with technetium-99m and on the morphology of the red blood cells

    Arctium lappa (burdock) has been used to treat inflammatory processes. Blood constituents labeled with technetium-99m (99mTc) have been utilized in nuclear medicine. It was evaluated the influence of a burdock extract on the labeling of blood constituents with 99mTc and on the morphometry of red blood cells. Blood samples from Wistar rats were incubated with burdock extract and the radiolabeling procedure was carried out. Plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were separated. The radioactivity in each fraction was counted and the percentages of radioactivity (%ATI) were determined. Morphology and morphometric (perimeter/area ratio) measurements of red blood cells (RBC) were performed. The incubation with burdock extract significantly (p99mTc obtained in this study. (author)

  4. Selective intracoronary injection of technetium 99m-labelled microspheres (outcome of 83 examinations)

    Coronarography supplies little information on the functional repercussions of a coronary stenosis and the state of the downstream arteriole bed. To overcome these inadequacies and to clarify the indications of aorta-coronary bridging, human albumin particles (microspheres or macro-aggregates) are injected into the coronary trunks during coronarography. The advantage of microspheres over macro-aggregates is their perfectly calibrated diameter (15+-5 microns). In the authors experience, and ours based on 83 examinations, the method presents no particular danger and adds very little to the time taken by conventional coronarography. For the method to be considered reliable it must be proved that the heterogeneities of distribution always correspond to anomalies of the coronary circulation, which seems not always to be the case. Our experience tends to show that as long as a hypoactivity zone or a scintigraphic blank cannot be referred with certainty to an actual functional or anatomical anomaly of the myocardium circulation this examination cannot be used as an argument for or against aorta-coronary bridging nor to predict its development. Where the study of angina pectoris with healthy coronaries is concerned a greater number of observations would be necessary in order to estimate, in cases of normal coronarography, to what extent anomalies of the coronary micro-circulation are responsible. In any case the difficulty of eliminating artefacts is a major obstacle to the reliability of the method. Radioelements such as 43K or 201Tl injected intraveinously seem to offer, more simply and without the risk of artefacts, the information looked for on labelled microsphere scintigraphs

  5. Tissue-targeting lead generation and optimization from random and directed screening of technetium-99m labeled tripeptide complex libraries in vivo

    ZENG Jun; LIU Ci-yi; XIE Wen-hui; HU Si-long; JIN Mu-xiu

    2006-01-01

    Background Screening libraries against a molecular target in vitro are idealized models that cannot reflect the real state in vivo where biomolecules coexist and interact. C-terminal amide tripeptides labelled with Technetium-99m can provide a unique noninvasive approach to trace a large number of compounds in vivo.Methods The C-terminal amide tripeptide libraries were synthesized on Rink Amide-MBHA resin using iterative and pooling protocol. Technetium (Ⅴ) oxo core [TcO3+] was bound to each tripeptide via 4 deprotonated nitrogen atoms to form a library of 8000 99mTc tripeptoid complexes. The radiocombinatorial screening (RCS) in vivo was carried out on SD rats and A549 tumour bearing mice.Results Signals of tissue distribution and metabolism of libraries were recorded by counting or imaging and tissue targeting leads identified by both random and directed RCS. Among them, 99mTc RPA, 99mTc VIG and 99mTc RES had specific tissue targeting in kidney, liver and tumour respectively. The percent injected dose per gram tissue of 99mTc labelled leads in their target tissue was highly structure dependent. Because the nontarget tissue binding and the metabolism of 99mTc tripeptoid sublibraries were simultaneously monitored successfully by RCS, the interference of background activity was limited to the lowest level. Optimization of renal function agent from the labelled libraries was carried out by directed screening. 99mTc DSG was finally identified the most promising agent for renal function studies.Conclusions RCS in vivo is a powerful tool for the discovery of tissue targeting drugs. The potential screening bias is probably the major limitation of labelled libraries.

  6. Synthesis and evaluation of Technetium-99m-labeled nitroimidazoles coupled to small peptides for imaging hypoxia

    Tumor cells are more sensitive to ionising radiation in the presence of oxygen than in its absence; even a small percentage of hypoxic cells within a tumor could limit the response of radiation. The non-invasive detection of solid tumor can be possible by using suitable 99mTc-Iabelled radiopharmaceuticals. Studies have been performed by various groups using 99mTc-Iabelled nitroimidazoles for imaging hypoxia. The objective of this work is to target tumor hypoxia with nitroimidazoles coupled to small bioactive peptides suitably functionalised for 99mTc radio labeling. This study may lead to the development of suitable radiopharmaceutical for hypoxia

  7. An introduction to technetium-99m generators

    The role played by technetium-99m generators in diagnostic medicine, their physical and chemical fundamentals and their main technical characteristics are discussed. This report is intended as a general introduction to a group of reports which summarize the work done on the development and production of the generators, and research on the chemical and physical aspects of the generator systems

  8. Technetium-99m labeling and fibronectin binding ability of Corynebacterium diphtheriae; Marcacao de Corynebacterium diphtheriae com Tecnecio-99m e avaliacao da capacidade de ligacao a fibronectina de plasma humano

    Souza, S.M.S.; Nagao, P.E.; Bernardo-Filho, M. [Universidade do Estado do Rio de Janeiro, RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes; Pereira, G.A.; Napoleao, F.; Andrade, A.F.B.; Hirata Junior, R.; Mattos-Guaraldi, A.L. [Universidade do Estado do Rio de Janeiro, RJ (Brazil). Faculdade de Ciencias Medicas

    2004-04-15

    The use of radionuclides has permitted advances in areas of clinical and scientific knowledge. Several molecules and cells have been labelled with Technetium-99m ({sup 99m}Tc). The stannous chloride (SnCl{sub 2}) has a significant influence on the labeling and stability of {sup 99m}Tc radiotracers. The frequent risk of diphtheria epidemics has intensified interest in the virulence factors of Corynebacterium diphtheriae. Although studies have looked at potential adhesins including haemagglutinins and exposed sugar residues, the molecular basis of mechanisms of adherence remains unclear. Adherence of pathogens to mammalian tissues may be mediated by fibronectin (FN) found in body fluids, matrix of connective tissues, and cell surfaces. In the present study we evaluated the binding ability to human plasma FN by {sup 99m}Tc labeled-C.diphtheriae. Due to adverse effects of stannous ions, microorganisms were submitted to survival and filamentation induction assays. Data showed a dose dependent susceptibility to SnCl{sub 2} bactericidal effects. Cell filamentation was observed for concentrations of SnCl{sub 2} > 110 {mu}g/ml. Adherence levels of {sup 99m}Tc labelled 241strain to coverslips coated with 20 {mu}g/ml FN were higher (P = 0.0037) than coated with bovine serum albumin. FN binding by the sucrose fermenting 241 C. diphtheriae strain (8.9% + 2.6) was significantly lower (P=0.0139) than Staphylococcus aureus Cowan I strain (34.1% {+-} 1.2). Therefore, bacterial {sup 99m}Tc labeling represents an additional tool that may contribute to the comprehension of C. diphtheriae interactions with host receptors such as FN that act as biological organizers by holding bacterial cells in position and guiding their migration. (author)

  9. Scintigraphic imaging with technetium-99M-labelled ceftizoxime is a reliable technique for the diagnosis of deep sternal wound infection in rats

    Costa, Paulo Henrique Nogueira; Diniz, Simone Odilia Fernandes; Cardoso, Valbert Nascimento; Tarabal, Bernardo; Takenaka, Isabella; Braga, Otavio; Vidigal, Paula Vieira Teixeira; Gelape, Claudio Leo; Araujo, Ivana Duval, E-mail: phnc@uol.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2015-07-01

    Purpose: to evaluate whether scintigraphy with technetium-99m-labeled ceftizoxime ({sup 99m}Tc-CFT) can differentiate mediastinitis from aseptic inflammation associated with sternotomy. Methods: twenty female Wistar rats were randomly distributed into four groups: S (control) -partial upper median sternotomy with no treatment; SW (control) - sternotomy and treatment of sternal wounds with bone wax; SB - sternotomy and infection with Staphylococcus aureus; SWB - sternotomy with bone wax treatment and bacterial infection. Scintigraphy with {sup 99m}Tc-CFT was performed eight days after surgery and images were collected 210 and 360 min after infusion of the radiopharmaceutical. Results: no animals exhibited clinical signs of wound infection at the end of the experiment, although histological data verified acute inflammatory response in those experimentally infected with bacteria. Scintigraphic images revealed that tropism of {sup 99m}Tc-CFT to infected sternums was greater than to their non-infected counterparts. Mean counts of radioactivity in bacteria-infected sternal regions (SB and SWB) were significantly higher (p = 0.0007) than those of the respective controls (S and SW).Conclusion: scintigraphy with technetium-99m-labeled ceftizoxime is a method that can potentially detect infection post sternotomy and differentiate from aseptic inflammation in animals experimentally inoculated with S. aureus (author)

  10. Scintigraphic imaging with technetium-99M-labelled ceftizoxime is a reliable technique for the diagnosis of deep sternal wound infection in rats

    Purpose: to evaluate whether scintigraphy with technetium-99m-labeled ceftizoxime (99mTc-CFT) can differentiate mediastinitis from aseptic inflammation associated with sternotomy. Methods: twenty female Wistar rats were randomly distributed into four groups: S (control) -partial upper median sternotomy with no treatment; SW (control) - sternotomy and treatment of sternal wounds with bone wax; SB - sternotomy and infection with Staphylococcus aureus; SWB - sternotomy with bone wax treatment and bacterial infection. Scintigraphy with 99mTc-CFT was performed eight days after surgery and images were collected 210 and 360 min after infusion of the radiopharmaceutical. Results: no animals exhibited clinical signs of wound infection at the end of the experiment, although histological data verified acute inflammatory response in those experimentally infected with bacteria. Scintigraphic images revealed that tropism of 99mTc-CFT to infected sternums was greater than to their non-infected counterparts. Mean counts of radioactivity in bacteria-infected sternal regions (SB and SWB) were significantly higher (p = 0.0007) than those of the respective controls (S and SW).Conclusion: scintigraphy with technetium-99m-labeled ceftizoxime is a method that can potentially detect infection post sternotomy and differentiate from aseptic inflammation in animals experimentally inoculated with S. aureus (author)

  11. Technetium-99m Sestamibi in Multiple Myeloma

    Technetium-99m 2-methoxy - isobutyl - isonitrile (99mTc-MIBI) has been reported to be useful in evaluating patients with multiple myeloma. The aim of this study is to evaluate the role of technetium-99m sestamibi (99mTc-MIBI) scintigraphy in the diagnosis. staging and follow-up of patients with multiple myeloma. Methods and Materials: twenty-five consecutive patients with multiple myeloma were studied using 99mTc- MIBI. Of the 25 patients included in this study, 6 were in stage I, II in stage II and 8 in stage III. Anterior and posterior whole-body imaging were obtained 20 min after I.V. injection of 740 MBq of 99mTc-MIBI. Four different MIBI patterns could be described in our patients: physiological (P), diffuse (D), focal (F) and combined diffuse and focal (D+F). All patients in stages II and III as well as 3 patients in stage I were treated with chemotherapy (cyclophosphamide and prednisone) then 99mTc-MlBI scans were repeated after 6 courses. Results: in comparison to conventional X-ray skeletal survey, 99mTc-MIBI scans showed a higher number of myeloma bone disease at diagnosis. All patients with stage II and III multiple myeloma were positive with 99mTc-MlBl scans at diagnosis. The pattern of positive MIBI accumulation was diffuse in 13 (52%) patients, focal in 4 (16%) and combined focal and diffuse in 6 (24%) patients. The intensity of 99mTc-MIBI correlated with disease activity as determined by lactate dehydrogenase (LDH), number of plasma cells in bone marrow and serum electrophoresis. There was a direct correlation between 99mTc-MIBI scan result and clinical outcome of patients following 6 courses of chemotherapy. Sensitivity and specificity of 99mTc-MIBI scintigraphy in detecting myeloma bone lesions were 92% and 90% respectively. Conclusion: 99mTc-MIBI scintigraphy is a reliable method to evaluate bone marrow activity in patients with multiple myeloma and follow-up of myeloma bone lesions

  12. Measurement of the distribution of lung perfusion. Comparison of the results obtained after injection of microspheres labelled with technetium 99m and after injection of xenon 133

    To validate the measurement of the distribution of lung perfusion carried out following injection of xenon 133 and by the detection of lung radio-activity, using a scintillation camera, the results obtained with those given by the injection of microspheres using technetium 99m are compared. The results of both methods are statistically comparable. The injection of xenon is preferred to the injection of technetium labelled microspheres for it also permits one to carry out radio-isotopic angiopneumography, the measurement of respiratory flows and the demonstration of hypoventilated areas of the lung

  13. Consequences of the magnetic field, sonic and radiofrequency waves and intense pulsed light on the labeling of blood constituents with technetium-99m

    Sources of magnetic field, radiofrequency and audible sonic waves and pulsed light have been used in physiotherapy to treat different disorders. In nuclear medicine, blood constituents(Bl-Co) are labeled with technetium-99m (99mTc) are used. This study evaluated the consequences of magnetic field, radiofrequency and audible sonic waves and intense pulsed light sources on the labeling of Bl-Co with 99mTc. Blood from Wistar rats was exposed to the cited sources. The labeling of Bl-Co with 99mTc was performed. Blood not exposed to the physical agents was used(controls). Data showed that the exposure to the different studied sources did not alter significantly (p>0.05) the labeling of Bl-Co. Although the results were obtained with animals, the data suggest that no alteration on examinations performed with Bl-Co labeled with 99mTc after exposition to the cited agents. The biological consequences associated with these agents would be not capable to interfere with some properties of the Bl-Co. (author)

  14. Consequences of the magnetic field, sonic and radiofrequency waves and intense pulsed light on the labeling of blood constituents with technetium-99m

    Meyer, Patricia Froes; Costa, Iris do Ceu Clara; Brandao-Neto, Jose; Medeiros, Aldo da Cunha [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Programa de Pos-graduacao em Ciencias da Saude; Santos-Filho, Sebastiao David; Adenilson de Souza da Fonseca; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental; Ariel Ronzio, Oscar [Universidad de Buenos Aires (Argentina); Bonelli, Ludmila [Universidade Salgado de Oliveira, Belo Horizonte, MG (Brazil)

    2007-09-15

    Sources of magnetic field, radiofrequency and audible sonic waves and pulsed light have been used in physiotherapy to treat different disorders. In nuclear medicine, blood constituents(Bl-Co) are labeled with technetium-99m ({sup 99m}Tc) are used. This study evaluated the consequences of magnetic field, radiofrequency and audible sonic waves and intense pulsed light sources on the labeling of Bl-Co with {sup 99m}Tc. Blood from Wistar rats was exposed to the cited sources. The labeling of Bl-Co with {sup 99m}Tc was performed. Blood not exposed to the physical agents was used(controls). Data showed that the exposure to the different studied sources did not alter significantly (p>0.05) the labeling of Bl-Co. Although the results were obtained with animals, the data suggest that no alteration on examinations performed with Bl-Co labeled with {sup 99m}Tc after exposition to the cited agents. The biological consequences associated with these agents would be not capable to interfere with some properties of the Bl-Co. (author)

  15. Effect of an extract of Artemisia vulgaris L. (Mugwort) on the in vitro labeling of red blood cells and plasma proteins with technetium-99m

    The aim of this work was to evaluate the effect of an extract of the Artemisia vulgaris L. (mugwort) on the labeling of blood constituents with technetium-99m (99mTc). Blood samples from Wistar rats were incubated with a mugwort extract and the radiolabeling of blood constituents was carried out. Plasma and blood cells were separated by centrifugation. Aliquots of plasma and blood cells were also precipitated with trichloroacetic acid and centrifuged to isolate soluble and insoluble fractions of plasma and blood cells. Radioactivity in each fraction was counted and the percentages of radioactivity (%ATI) was calculated. Mugwort extract decreased significantly (p<0.05) the %ATI on the blood compartments and on the blood cells proteins (insoluble fraction). The analysis of the results indicates that the extract could have substances that could interfere on the transport of stannous through the erythrocyte membrane altering the labeling of blood cells with 99mTc. (author)

  16. Studies on technetium-99m-labelled monophosphates: 1,2-epoxypropylphosphonic acid and its hydrolysed form

    Neves, M.; Paulo, A.; Castanheira, I.; Patricio, L. (Laboratorio Nacional de Engenharia e Tecnologia Industrial, Sacavem (Portugal). Dept. de Radioisotopos)

    1992-06-01

    1,2-Epoxypropylphosphonic acid (fosfomycin) when labelled with {sup 99m}Tc at pH - 6.8 was described as a renal imaging agent. Under the same experimental conditions, except pH=2.5, {sup 99m}Tc fosfomycin has shown bone uptake. The hydrolysed form of fosfomycin, the 1,2-dihydroxypropyl-1-phosphonic acid when labelled with {sup 99m}Tc in identical conditions, also has shown similar biological behaviour. Extraction and adsorption experiments conducted on both radiopharmaceuticals have shown that renal uptake preparations are Tc(V) complexes, meanwhile bond uptake preparations are Tc(IV) and/or Tc(III) complexes. (Author).

  17. Dissemination of bacteria labeled with technetium-99m after laparotomy and abdominal insufflation with different CO2 pressures on rats; Disseminacao de bacterias marcadas com tecnecio-99m apos laparotomia e insuflacao com diferentes pressoes de CO2 em ratos

    Pitombo, Marcos Bettini; Faria, Clarice Abreu dos Santos Albuquerque de; Steinbruck, Klaus [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Escola de Medicina]. E-mail: mpitombo@urbi.com.br; Bernardo, Luciana Camargo; Bernardo Filho, Mario[Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes (IBRAG). Lab. de Radiofarmacia Experimental

    2008-01-15

    Purpose: To asses the dissemination of bacteria labeled with technetium-99m (99mTc) from peritoneal cavity after different surgical procedures. Methods: Bacteria of the Escherichia coli species labeled with 99mTc were used in a concentration of 108 units of colony-makers for ml (UFC/ml) and 1 ml was inoculated through intra-peritoneal via. Forty-eight rats were divided into four groups: control, laparotomy, pneumoperitoneum with 10 mmHg and pneumoperitoneum with 20 mmHg of CO2. Procedures were performed 20 min after injection of the inoculum and lasted 30 min. Animals were sacrificed after six hours (Group 1) and 24 hours (Group 2). Samples of blood, liver and spleen were collected for radioactivity counting. Results: After six hours, indirect detection of the bacteria in different organs was uniform in all groups. After 24 hours, a larger detection of technetium was observed in the livers of animals of the group insufflated with 20 mmHg of CO2, when compared with those of control group (p<0.01). The other groups did not present statistically significant variations. Conclusions: The use of a higher intra-abdominal pressure was associated with a higher bacterial dissemination to the liver. The application of lower intra-abdominal pressures may be associated with a lower dissemination of the infectious status during laparoscopic approach of peritonitis status. (author)

  18. Labeling of new formulation of tin-sucralfate freeze-dried kit with technetium-99m and its biological evaluation

    The present investigation deals with a simple preparation of new formulation of tin-sucralfate freeze-dried kit (F.D.K.), to be directly labeled with 99mTc at optimal pH value of 7.0. The lyophilized form containing 100 mg sucralfate and 11.3 mg dihydrated stannous chloride. Other optimal pH values of the preparation were found to be from 4.0 to 11.0. The range of sucralfate amount studied (50-500 mg) not affected the radiochemical purity of the labeled complex. The radiochemical purity and the stability of the labeled preparation that assessed by filtration were more than 95%. 99mTc sucralfate was radiochemical stable up to a specific activity of 1,000 mCi per gram which was more stable than earlier published value (700 mCi per gram) without any radiolytic decomposition. The biological behavior of 99mTc-pertechnetate was evaluated in two groups of animals, the first group (neither fasted nor ulcerated) and the second group (fasted and ulcerated mice). The data of organ distribution of 99mTc-sucralfate in ulcerated fasted mice showed that more than 99% of the administered dose was accumulated in the stomach (87.92%) and intestine (11.43%). The radioanalytical results together with the in vivo-biological behavior of the labeled preparation demonstrate it's stability, efficacy and usefulness in medical applications for the detection of gastrointestinal ulcers. (author)

  19. Effect of Peumus boldus on the labeling of red blood cells and plasma proteins with Technetium-99m

    Peumus boldus is used in popular medicine in Brazil. The influence of Peumus boldus on the labeling of red blood cells and plasma proteins with 99mTc was studied. Stannous chloride and 99mTc pertechnetate were incubated with blood and a tincture of Peumus boldus. Aliquots of plasma and blood cells were isolated from the mixture and treated with trichloroacetic acid (TCA). After separation, analysis of the soluble and insoluble fractions showed a rapid uptake of the radioactivity by blood cells in the presence of the drug, whereas there was a slight decrease in the amount of 99mTc radioactivity in the TCA-insoluble fraction of plasma

  20. Effect of Peumus boldus on the labeling of red blood cells and plasma proteins with Technetium-99m

    Wancke Reiniger, Ingrid; Fonseca de Oliveira, Joelma; Caldeira-de-Araujo, Adriano [Departamento de Biofisica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Bernardo-Filho, Mario [Instituto Nacional de Cancer, Centro de Pesquisa Basica, Rio de Janeiro, RJ (Brazil)

    1999-08-01

    Peumus boldus is used in popular medicine in Brazil. The influence of Peumus boldus on the labeling of red blood cells and plasma proteins with {sup 99m}Tc was studied. Stannous chloride and {sup 99m}Tc pertechnetate were incubated with blood and a tincture of Peumus boldus. Aliquots of plasma and blood cells were isolated from the mixture and treated with trichloroacetic acid (TCA). After separation, analysis of the soluble and insoluble fractions showed a rapid uptake of the radioactivity by blood cells in the presence of the drug, whereas there was a slight decrease in the amount of {sup 99m}Tc radioactivity in the TCA-insoluble fraction of plasma.

  1. Effect of Peumus boldus on the labeling of red blood cells and plasma proteins with technetium-99m.

    Reiniger, I W; de Oliveira, J F; Caldeira-de-Araújo, A; Bernardo-Filho, M

    1999-08-01

    Peumus boldus is used in popular medicine in Brazil. The influence of Peumus boldus on the labeling of red blood cells and plasma proteins with 99mTc was studied. Stannous chloride and 99mTc pertechnetate were incubated with blood and a tincture of Peumus boldus. Aliquots of plasma and blood cells were isolated from the mixture and treated with trichloroacetic acid (TCA). After separation, analysis of the soluble and insoluble fractions showed a rapid uptake of the radioactivity by blood cells in the presence of the drug, whereas there was a slight decrease in the amount of 99mTc radioactivity in the TCA-insoluble fraction of plasma. PMID:10376326

  2. Biodistribution and preparation of technetium-99m-labeled D-D3 monoclonal antibody against pro-gastrin-releasing peptide (31-98) in mice

    HAO Li-jun; HONG Zhi-hui; SHI Yi-zhen; LIU Zeng-li; ZHOU Xiao-lin

    2013-01-01

    Background We previously reported that iodine-131(131I)-labeled anti-pro-gastrin-releasing peptide (ProGRP(31-98)) monoclonal antibody D-D3 could selectively accumulate in the tumor sites of nude mice bearing small cell lung cancer (SCLC) xenografts.However,131I-D-D3 was cleared slowly from the body,and the best radioimmunoimaging time for SCLC was 72-96 hours after injection.The aims of this study were to radiolabel anti-ProGRP(31-98) D-D3 monoclonal antibody with technetium-99m (99mTc) and to investigate the biodistribution of this antibody in healthy ICR mice.Methods D-D3 was labeled with 99mTc via the 2-mercaptoethanol reduction method.99mTc-D-D3 was purified by the gel column separation method.The labeling efficiency and radiochemical purity were measured by thin-layer chromatography.The immunological activity of 99mTc-D-D3 was determined with cell conjugation assays.99mTc-D-D3 was injected into healthy ICR mice via a tail vein,and all the healthy ICR mice were sacrificed by cervical dislocation at a designated time.Then,the blood and major organs were removed and weighed,and counted in a gamma scintillation counter to determine the percentage of the injected dose per gram (%ID/g).Results The labeling rate and the radiochemical purity of 99mTc-D-D3 were (73.87±2.89)% and (94.13±4.49)%,respectively.The immunobinding rates of 99mTc-D-D3 to the human small cell lung cancer NCl-H446 cell line and lung adenocarcinoma A549 cell line were (81.2±2.37)% and (24.3±1.46)%,respectively.The distribution data of normal ICR mice demonstrated that 99mTc-D-D3 was mainly distributed in the liver,kidney and lung,and less in the brain tissue and muscle.Conclusions 99mTc-D-D3 antibody not only had high radiochemical purity,but also had good stability both in vitro and in vivo,and maintained good immunological activity.99mTc-D-D3 was metabolized mainly in the kidney and liver,and the blood radioactivity decreased rapidly.Thus,99mTc-D-D3 is conducive to the

  3. Effects of fenoprofen on the labeling of blood constituents with technetium-99m, the morphology of red blood cells and the plasmid

    Pereira, Marcia de Oliveira; Rocha, Gabrielle de Souza [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Ciencias da Saude; Lombardi, Simone dos Santos; Santos-Filho, Sebastiao David; Fonseca, Adenilson de Souza da; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Instituto de Biologia Roberto Alcantara Gomes. Dept. de Biofisica e Biometria]. E-mail: adenilso@uerj.br; Pereira, Mario Jose [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Fisiologia; Geller, Mauro [Centro Universitario Serra dos Orgaos, Teresopolis, RJ (Brazil). Centro de Ciencias da Saude

    2008-12-15

    The aim of this work was to evaluate the effect of fenoprofen on the labeling of blood constituents with technetium- 99m, on the morphology of red blood cells and on the plasmid DNA. Blood samples from Wistar rats were incubated with fenoprofen and the assay of labeling of blood constituents with technetium-99m ({sup 99m}Tc) was performed. Blood cells, plasma, soluble and insoluble fractions of blood cells and plasma were separated. The radioactivity in each fraction was counted and percentage of incorporated radioactivity (%ATI) was determined. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphology of the red blood cells (RBC) was evaluated. Plasmid (pBSK) was incubated with fenoprofen with stannous chloride, and agarose gel electrophoresis procedure was carried out to evaluate genotoxic and the protection of this drug against stannous chloride effect on DNA. In conclusion, under the conditions used in this work, our data suggest that fenoprofen would not affect the fixation of the {sup 99m}Tc on the blood constituents, alter the RBC membrane and present genotoxic and redox effects. (author)

  4. Technetium-99m myocardial imaging agents

    A major focus of cardiovascular radiopharmaceutical research over the past decade has been the search for a Tc-99m agent that could replace Tl-201, the current agent of choice for myocardial perfusion imaging. Recent advances in the inorganic chemistry of technetium, and in the translation of this chemistry to radiopharmaceutical development, make it very likely that this search will soon be successfully completed

  5. Cyclotron Production of Technetium-99m

    Gagnon, Katherine M.

    Technetium-99m (99mTc) has emerged as the most widely used radionuclide in medicine and is currently obtained from a 99Mo/ 99mTc generator system. At present, there are only a handful of ageing reactors worldwide capable of producing large quantities of the parent isotope, 99Mo, and owing to the ever growing shutdown periods for maintenance and repair of these ageing reactors, the reliable supply 99mTc has been compromised in recent years. With an interest in alternative strategies for producing this key medical isotope, this thesis focuses on several technical challenges related to the direct cyclotron production of 99mTc via the 100Mo(p,2n)99mTc reaction. In addition to evaluating the 100Mo(p,2n)99mTc and 100Mo(p,x)99Mo reactions, this work presented the first experimental evaluation of the 100Mo(p,2n) 99gTc excitation function in the range of 8-18 MeV. Thick target calculations suggested that large quantities of cyclotron-produced 99mTc may be possible. For example, a 6 hr irradiation at 500 μA with an energy window of 18→10 MeV is expected to yield 1.15 TBq of 99mTc. The level of coproduced 99gTc contaminant was found to be on par with the current 99Mo/99mTc generator standard eluted with a 24 hr frequency. Highly enriched 100Mo was required as the target material for 99mTc production and a process for recycling of this expensive material is presented. An 87% recovery yield is reported, including metallic target preparation, irradiation, 99mTc extraction, molybdate isolation, and finally hydrogen reduction to the metal. Further improvements are expected with additional optimization experiments. A method for forming structurally stable metallic molybdenum targets has also been developed. These targets are capable of withstanding more than a kilowatt of beam power and the reliable production and extraction of Curie quantities of 99mTc has been demonstrated. With the end-goal of using the cyclotron-produced 99mTc clinically, the quality of the cyclotron

  6. Effect of plasmapheresis on the liver uptake of ApoB-lipoproteins labeled with technetium-99m

    To study liver low density lipoprotein (LDL)-receptor activity before and after plasmapheresis, [99mTc] very low density lipoprotein (VLDL) was used. Autologous VLDL was labeled, sterilized by filtration, and administered intravenously to patients under a gamma camera. The uptake of lipoproteins in the liver was measured by scintiscanning. Liver activity curves were generated for each patient. The liver activity in patients with the heterozygous form of familial hypercholesterolemia (FH) and in patients with symptomatic atherosclerosis (SA) without hereditary deficit of LDL receptors was reduced as compared to healthy people. Plasmapheresis enhanced the liver uptake of the 99mTc-labeled lipoproteins in atherosclerotic patients. Thus, labeled metabolites could presumably be of use in assessing the effect of plasmapheresis on liver function

  7. Under used technetium-99m generators

    Health care reform truly has become a global issue and it will undoubtedly have a dramatic impact on the future of nuclear medicine business in particular. A bigger concern within the nuclear medicine community is its competitiveness with other modalities and cost effectiveness.Technetium-99m and its generators are playing key role for the majority of diagnostic scans performed in the world today. Availability of ''9''9''mTc can be increased if it is separated from ''9''9Mo after much shorter growth times. After proper planning with the extra ''9''9''mTc, a significant number of scans can be performed or we would be able to order approximately 30% low activity ''9''9Tc generators to fulfill our requirements

  8. Preparation and in vivo biological investigations on a novel radioligand for bone scanning: technetium-99m-labeled zoledronic acid derivative

    Lin Jianguo; Qiu Ling, E-mail: qiulingwx@gmail.com; Cheng Wen; Luo Shineng; Ye Wanzhong

    2011-07-15

    Introduction: To enable imaging at an earlier time after injection, a radiopharmaceutical with higher affinity for bone, larger ratio of bone-to-soft tissue uptake and more rapid clearance from blood is required. The nature of diphosphonic acid is a key factor to determine the advantages of the radiopharmaceuticals. The purpose of this study is to optimize the linker chain between the imidazolyl and geminal diphosphonate group in the zoledronic acid (ZL) to develop novel single photon emission computed tomography (SPECT) bone imaging agent. Methods: A novel ZL derivative, 1-hydroxy-3-(1H-imidazol-1-yl)propane-1,1-diyldiphosphonic acid (IPrDP), was successfully prepared and labeled with {sup 99m}Tc in a high labeling yield. Biodistribution of {sup 99m}Tc-IPrDP and {sup 99m}Tc-ZL in normal mice were studied and compared. SPECT bone scanning was performed on the rabbit and a series of dynamic and static images were recorded by Philips SKY Light emission computed tomography. Results: In the biodistribution studies, {sup 99m}Tc-IPrDP exhibits significant advantages on the bone resorption and the clearance from soft tissues compared with {sup 99m}Tc-ZL. Kinetics of blood clearance in mice showed that T{sub 1/2{alpha}} and T{sub 1/2{beta}} of {sup 99m}Tc-IPrDP were 1.47 min and 46.47 min, while those of {sup 99m}Tc-ZL were 2.28 and 52.63 min respectively. Excellent images of the rabbit skeleton can be quickly obtained for {sup 99m}Tc-IPrDP, which was faster than {sup 99m}Tc-ZL and the clinically widely used bone imaging agent {sup 99m}Tc-MDP (technetium-99m labeled with methylenediphosphonate). Conclusions: {sup 99m}Tc-IPrDP possesses excellent characteristics for the potential application as a novel bone scanning agent.

  9. Consequences of the magnetic field, sonic and radiofrequency waves and intense pulsed light on the labeling of blood constituents with technetium-99m

    Patricia Froes Meyer

    2007-09-01

    Full Text Available Sources of magnetic field, radiofrequency and audible sonic waves and pulsed light have been used in physiotherapy to treat different disorders. In nuclear medicine, blood constituents(Bl-Co are labeled with technetium-99m (99mTc are used. This study evaluated the consequences of magnetic field, radiofrequency and audible sonic waves and intense pulsed light sources on the labeling of Bl-Co with 99mTc. Blood from Wistar rats was exposed to the cited sources. The labeling of Bl-Co with 99mTc was performed. Blood not exposed to the physical agents was used(controls. Data showed that the exposure to the different studied sources did not alter significantly (p>0.05 the labeling of Bl-Co. Although the results were obtained with animals, the data suggest that no alteration on examinations performed with Bl-Co labeled with 99mTc after exposition to the cited agents. The biological consequences associated with these agents would be not capable to interfere with some properties of the Bl-Co.Fontes de campo magnético, ondas sonoras audíveis e de radiofreqüência e luz intensa pulsada são usadas para o tratamento de doenças. Constituintes sangüíneos(CS marcados com tecnécio-99m(99mTc são utilizados na medicina nuclear. Esse trabalho avaliou as consequências de fontes de campo magnético, ondas sonoras audíveis e de radiofreqüência e luz intensa pulsada na marcação de CS com 99mTc. Sangue de ratos Wistar foi exposto às fontes citadas. A marcação de CS com 99mTc foi realizada. Sangue não exposto foram utilizadas(controle. Resultados mostraram que os agentes físicos estudados não alteraram significativamente (p>0.05 a radiomarcação de CS. Apesar terem sido obtidos com sangue de animais, os resultados sugerem que nenhuma alteração nos exames realizados com constituintes sangüíneos com 99mTc em medicina nuclear ocorreria após a exposição às fontes avaliadas. As consequências biológicas associadas a esses agentes não seriam

  10. Uncaria tomentosa extract: evaluation of effects on the in vitro and in vivo labeling of blood constituents with technetium-99m

    Moreno, Silvana Ramos Farias; Olej, Beni; Arnobio, Adriano; Caldas, Luiz Querino de Araujo [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)]. E-mail: srfmoreno@hotmail.com; Carvalho, Jorge Jose de; Nascimento, Ana Lucia [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Histologia e Embriologia; Rocha, Emely Kazan [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Biologia Celular e Genetica; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Biofisica e Biometria; Honeycut, Hayden [University of North Carolina, Chapel Hill, NC (United States). School of Pharmacy

    2008-12-15

    The influence (in vivo and in vitro) of an Uncaria tomentosa extract (Cats claw) on the labeling of red blood cells (RBCs) and plasma and cellular proteins with technetium-99m (Tc-99m) was evaluated. For the in vivo treatment, animals were treated with Cats claw. For the in vitro treatment, heparinized blood was incubated with Cats claw before the addition of stannous chloride (SnCl{sub 2}) and Tc-99m. Samples of plasma (P) and RBCs were separated and also precipitated with trichloroacetic acid. The soluble and insoluble fractions of P and RBCs were isolated. The analysis of the results of the in vivo study, indicates that there is no significant alteration on the uptake of Tc-99m by the blood constituents, but it significantly decrease (p<0.05) the labeling of blood constituents by in vitro methods. These effects could be due to chelation of stannous and /or pertechnetate ions and blockage of the Tc-99m bindings sites. (author)

  11. Effect of adenine on bacterial translocation using technetium-99m labeled E. coli in an intestinal obstruction model in rats

    This study aims to investigate effects of adenine on bacterial translocation (BT) using 99mTc-labeled E. coli in an intestinal obstruction rat model. In the study twenty-one rats were used. The rats were divided into three groups according to different feeding patterns. The control group (CG) was fed with a standard chow diet for 7 days. Group A1 and group A2 were fed with adenine supplemented chow diet for 7 days. At the end of the feeding period, after all groups was submitted intestinal obstruction. 99mTc-E. coli was injected into the rats' terminal ileum under anesthetic. The rats were sacrificed under aseptic conditions at 24th h after the surgery. The uptake of 99mTc-E. coli was determined in organs such as the liver, mesenteric lymph nodes, spleen and ileum. Group A1 and group A2 results show that the uptake of 99mTc-E. coli decreased in the blood and organs comparing to the CG. As a result, it was observed that adenine reduced the level of BT when compared with CG. The beneficial effect of adenine on BT in intestinal obstruction was observed. However, further studies are needed to more clearly assess how this benefit can be achieved. (author)

  12. Synthesis of technetium-99m labeled clinafloxacin (99mTc-CNN) complex and biological evaluation as a potential Staphylococcus aureus infection imaging agent

    In the present study synthesis of the 99mTc-CNN complex and its efficacy as a prospective Staphylococcus aureus (S. aureus) infection imaging agent was assessed. The 99mTc-CNN complex was characterized in terms of stability in saline, serum, in vitro binding with S. aureus and in vivo percent absorption in male Wister rats (MWR) infected with live and heat killed S. aureus. Radiochemically the 99mTc-CNN complex showed stable behavior in saline and serum at different intervals. At 30 min after reconstitution the complex showed maximum radiochemical purity (RCP) yield of 97.55 ± 0.22%. The RCP yield decreased to 90.50 ± 0.18% within 240 min. In serum, 18.15% unwanted side product was appeared within 16 h of the incubation. In vitro saturated binding with S. aureus was observed at different intervals with a 62.00% maximum at 90 min. Normal percent in vivo uptake was observed in MWR artificially infected with live S. aureus with a five times higher in the infected muscle as compared to the inflamed and normal muscles. No difference in the percent uptake of the complex in MWR infected with heat killed S. aureus in the infected, inflamed and normal muscles were observed. Based on the promising in vitro and in vivo radiochemical and biological characteristics, we recommend the 99mTc-CNN complex for in vivo localization of the S. aureus infectious foci. (author)

  13. Lyophilized kits of diamino dithiol compounds for labelling with 99m-technetium. Pharmacokinetics studies and distribution compartmental models of the related complexes

    The present work reflects the clinical interest for labelling diamino dithiol compounds with technetium-99m. Both chosen compounds, L,L-Ethylene dicysteine (L,L-EC) and L,L-Ethylene dicysteine diethyl esther (L,L-ECD) were obtained with relative good yield and characterized by IR and NMR. The study of labelling conditions with technetium-99m showed the influence of the type and mass of reducing agent as well as the pH on the formation of complexes with desired biological characteristics. Radiochemical purity was determined by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Lyophilised kits of L,L-EC and L,L-ECD for labelling with 99mTc were obtained, with stability superior to 120 days, when stored under refrigeration, enabling the kits marketing. The ideal formulation of the kits as well as the use of liquid nitrogen in the freezing process, determined the lyophilization success. Distribution biological studies of the 99mTc complexes were performed on mice by invasive method and on bigger animals by scintigraphic evaluation. Biological distribution studies of the complex 99mTc-L,L-EC showed fast blood clearance, with the elimination of about 90% of the administered dose after 60 minutes, almost exclusively by the urinary system. The biological distribution results were adjusted to a three compartmental distribution model, as expected for a radiopharmaceutical designed to renal dynamic studies, with tubular elimination. The complex interaction with renal tubular receptors is related with structural characteristics of the compound, more specifically with the presence and location of polar groups. In comparison with 99mTc-L,L-EC, biological studies of the complex 99mTc -L,L-ECD showed different distribution aspects, despite some structural similarities. The presence of ethyl groups confers to the complex neutrality and lipophilicity. It cross the intact blood brain barrier and is retained in the brain for enough period, permitting

  14. Evaluation of the effect of an extract of sabugueiro (Sambucus australis) on the labeling of blood constituents with technetium-99m

    Ribeiro, Camila Godinho; Rebello, Bernardo Machado; Neves, Rosane de Figueiredo; Santos-Filho, Sebastiao David; Fonseca, Adenilson de Souza da [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental]. E-mail: cacagr@yahoo.com.br; Medeiros, Aldo da Cunha; Bernardo-Filho, Mario [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Centro de Ciencias da Saude. Programa de Pos-graduacao em Ciencias da Saude; Catanho, Maria Teresa Jansem de Almeida [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    2007-09-15

    Sambucus australis (sabugueiro) has been used to treat inflammatory and rheumatologic disorders. Blood constituents labeled with technetium-99m (99mTc) have been used in nuclear medicine to obtain diagnostic images. The aim of this work was to evaluate the effect of a sabugueiro extract on the labeling of blood cells with 99mTc. Blood samples from Wistar rats were incubated with sabugueiro extract and the radiolabeling assay of blood constituents was carried out. After centrifugation, samples of plasma and blood cells were separated. Aliquots of plasma and blood cells were precipitated with trichloroacetic acid and centrifuged to isolate soluble and insoluble fractions. The radioactivity in each fraction was counted and the percentage of activity (%ATI) was determined. Incubation with sabugueiro extract altered significantly (p<0.05) the %ATI incorporated to the blood constituents. These results could be explained due the presence of chemical substances in the sabugueiro extract that present redox and/or chelating action altering the labeling of the blood constituents with 99mTc. (author)

  15. Effect of an Arctium lappa (burdock) extract on the labeling of blood constituents with technetium-99m and on the morphology of the red blood cells

    Neves, Rosane de Figueiredo; Rebello, Bernardo Machado; Medeiros, Aldo da Cunha [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Programa de Pos-graduacao em Ciencias da Saude]. E-mail: nevesrosane@yahoo.com.br; Moreno, Silvana Ramos Farias; Fonseca, Adenilson de Souza da [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental; Caldas, Luiz Querino de Araujo [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Ciencias Medicas; Bernardo-Filho, Mario [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil). Coordenadoria de Pesquisa

    2007-09-15

    Arctium lappa (burdock) has been used to treat inflammatory processes. Blood constituents labeled with technetium-99m ({sup 99m}Tc) have been utilized in nuclear medicine. It was evaluated the influence of a burdock extract on the labeling of blood constituents with {sup 99m}Tc and on the morphometry of red blood cells. Blood samples from Wistar rats were incubated with burdock extract and the radiolabeling procedure was carried out. Plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were separated. The radioactivity in each fraction was counted and the percentages of radioactivity (%ATI) were determined. Morphology and morphometric (perimeter/area ratio) measurements of red blood cells (RBC) were performed. The incubation with burdock extract significantly (p<0.05) altered the %ATI on the blood compartments and the perimeter/area ratio of RBC, as well as, induced modifications on the shape of RBC. Alterations on membrane could justify the decrease of labeling of blood cells with {sup 99m}Tc obtained in this study. (author)

  16. Technetium-99m pyridoxylideneglutamate (P. G. ) cholescintigraphy

    Stadalnik, R.C.; Matolo, N.M.; Jansholt, A.L.; Krohn, K.A.; DeNardo, G.L.; Wolfman, E.F Jr.

    1976-12-01

    Technetium-99m P.G. cholescintigraphy was performed in 27 human volunteers and 81 patients referred for hepatobiliary tract disease. The gallbladder, biliary system, and gastrointestinal tract were well visualized in the normal patients and volunteers. The gallbladder was not visualized in 22 patients with histologically proved cholecystitis with cystic duct obstruction. Nine patients with complete extrahepatic obstruction of the common bile duct were correctly diagnosed. Hepatocellular disease and incomplete obstruction, with and without jaundice, were diagnosed with this technique. Oral cholecystography is superior to this method for the detection of cholelithiasis in nonjaundiced patients.

  17. Technetium-99m antibodies labeled with MAG3 and SHNH: An in vitro and animal in vivo comparison

    The in vitro stability and animal pharmacokinetics of 99mTc bound to Sandoz and C110 IgG antibodies via a modified MAG3 has been compared with the hydrazino nicotinamide (SHNH) moiety as standard. For both antibodies, the stabilities of the label to challenge at up to 50:1 cysteine: IgG molar ratio were comparable, but at higher molar ratios, MAG3 showed greater instabilities. For the Sandoz antibody, size-exclusion HPLC analysis of 37 degree sign C serum incubates and plasma samples from injected mice showed no clearly distinguishable differences. In the C110 case, some increased high molecular weight radioactivity was apparent with MAG3. Biodistributions in normal mice showed significant differences only in liver (Sandoz) and liver, spleen, intestines, stomach, and blood (C110), with SHNH usually providing higher levels. Thus, for two different antibodies and under the conditions of this study, the MAG3 chelator provided a 99mTc label with properties similar to that of SHNH moiety

  18. Estimation of cardiac output by first-pass data with technetium-99m-labeled myocardial perfusion imaging agent

    Technetium-99m-tetrofosmin, a myocardial perfusion imaging agent was used for estimation of cardiac output by means of first-pass radionuclide angiography performed in the anterior projection. Region of interests (ROIs) were assigned over right ventricle, left ventricle and whole chest, and time activity curves (TACs) were obtained. Cardiac output indices (COIs) were calculated by the following equation; COI=p3/2·Qc/∫0tA(s)ds, where p=number of pixels of the ventricular ROI, Qc=the peak count rate of the TAC obtained from the whole chest's ROI and ∫0tA(s)ds=the area under ventricular TAC. The COI(y) determined by ROI over the left ventricle yield the best correlation with the cardiac output by conventional radionuclide method (x) (y=0.0381x+6.22, r=0.828, n=48, p<0.001). In conclusion, cardiac output can be easily measured with first pass data using myocardial perfusion imaging agent. (author)

  19. Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

    The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m (99m Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99mTc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation. (author)

  20. Drug interaction with radiopharmaceuticals: effect on the labeling of red blood cells with Technetium-99m and on the bioavailability of radiopharmaceuticals

    Gomes, Maria Luisa; Oliveira, Marcia B. Nunes de [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria; Bernardo-Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria; Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil). Coordenadoria de Pesquisa

    2002-09-01

    The evidence that natural and synthetic drugs can affect radiolabeling or bioavailability of radiopharmaceuticals in setting of nuclear medicine clinic is already known. However, this drug interaction with radiopharmaceuticals (DIR) is not completely understood. Several authors have described the effect of drugs on the labeling of blood elements with Technetium-99m (99mTc) and on the biodistribution of radiopharmaceuticals. When the DIR is known, if desirable or undesirable, the natural consequence is a correct diagnosis. However, when it is unknown, it is undesirable and the consequences are the possibility of misdiagnosis and/or the repetition of the examination with and increase of radiation dose to the patient. The possible explanation to the appearance of DIR are radiopharmaceutical modification, alternation of the labeling efficiency of the radiopharmaceutical, modification of the target, modification of no target and/or the alteration of the binding of the radiopharmaceutical on the blood proteins. The effect of drugs on the labeling of blood elements with 99 mTc might be explained by a direct inhibition (chelating action) of the stannous and pertechnetate ions, damage induced in the plasma membrane, competition of the cited ions for the same binding sites, possible generation of reactive oxygen species that could oxidize the stannous ion and/or (v) direct oxidation of the stannous ion. In conclusion, the development of biological models to study the D IR is highly relevant. (author)

  1. Drug interaction with radiopharmaceuticals: effect on the labeling of red blood cells with Technetium-99m and on the bioavailability of radiopharmaceuticals

    The evidence that natural and synthetic drugs can affect radiolabeling or bioavailability of radiopharmaceuticals in setting of nuclear medicine clinic is already known. However, this drug interaction with radiopharmaceuticals (DIR) is not completely understood. Several authors have described the effect of drugs on the labeling of blood elements with Technetium-99m (99mTc) and on the biodistribution of radiopharmaceuticals. When the DIR is known, if desirable or undesirable, the natural consequence is a correct diagnosis. However, when it is unknown, it is undesirable and the consequences are the possibility of misdiagnosis and/or the repetition of the examination with and increase of radiation dose to the patient. The possible explanation to the appearance of DIR are radiopharmaceutical modification, alternation of the labeling efficiency of the radiopharmaceutical, modification of the target, modification of no target and/or the alteration of the binding of the radiopharmaceutical on the blood proteins. The effect of drugs on the labeling of blood elements with 99 mTc might be explained by a direct inhibition (chelating action) of the stannous and pertechnetate ions, damage induced in the plasma membrane, competition of the cited ions for the same binding sites, possible generation of reactive oxygen species that could oxidize the stannous ion and/or (v) direct oxidation of the stannous ion. In conclusion, the development of biological models to study the D IR is highly relevant. (author)

  2. Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

    P Chattopadhyay

    2012-01-01

    Full Text Available The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m (99m Tc-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma-scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99mTc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation.

  3. Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

    Chattopadhyay, P; Pandey, A; Goyary, D; Chaurasia, A; Singh, L; Veer, V. [Division of Pharmaceutical Technology, Defence Research Laboratory, Assam (India); Department of Life Sciences, Defense Research Development and Organization, New Delhi (India)

    2012-07-01

    The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m ({sup 99m} Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of {sup 99m}Tc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation. (author)

  4. Synthesis and biological evaluation of one novel technetium-99m-labeled nitroquipazine derivative as an imaging agent for serotonin transporter

    Guo Yunhang; Chen Xiangji; Jia Hongmei; Ji Xinmin [Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Liu Boli [Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875 (China)], E-mail: liuboli@bnu.edu.cn

    2008-12-15

    Imaging of serotonin transporter (SERT) by positron emission tomography (PET) or single-photon emission-computed tomography (SPECT) in humans would provide useful information in diagnosis and therapy of several neurodegenerative and neuropsychiatric disorders. 6-Nitroquipazine is a highly potent and selective inhibitor of the SERT. For the development of new {sup 99m}Tc-labeled 6-nitroquipazine derivatives as SERT imaging agents, novel [N-[2-((3-(4-(6-nitroquinolin-2-yl)piperazin-1-yl)propyl)(2-mercaptoethyl) amino]-acetyl-2-aminoethanethiolato] [{sup 99m}Tc]technetium (V) oxide ({sup 99m}Tc-MAMA-3-PQ) and its rhenium analog were synthesized and characterized. {sup 99m}Tc-MAMA-3-PQ displayed high initial brain uptake (0.52% ID/organ at 2 min post-injection (pi)) and relatively fast washout in mice (0.09% ID/organ at 60 min pi). The regional brain distribution studies in rats showed high-specific binding ratios at 60 min pi. Maximum regional contrast ratio observed for thalamus/cerebellum was 2.94, followed by 2.62 for hypothalamus/cerebellum. These encouraging results lead us to further explore its derivatives as new imaging agents for the SERT in the brain.

  5. Synthesis and biological evaluation of one novel technetium-99m-labeled nitroquipazine derivative as an imaging agent for serotonin transporter

    Imaging of serotonin transporter (SERT) by positron emission tomography (PET) or single-photon emission-computed tomography (SPECT) in humans would provide useful information in diagnosis and therapy of several neurodegenerative and neuropsychiatric disorders. 6-Nitroquipazine is a highly potent and selective inhibitor of the SERT. For the development of new 99mTc-labeled 6-nitroquipazine derivatives as SERT imaging agents, novel [N-[2-((3-(4-(6-nitroquinolin-2-yl)piperazin-1-yl)propyl)(2-mercaptoethyl) amino]-acetyl-2-aminoethanethiolato] [99mTc]technetium (V) oxide (99mTc-MAMA-3-PQ) and its rhenium analog were synthesized and characterized. 99mTc-MAMA-3-PQ displayed high initial brain uptake (0.52% ID/organ at 2 min post-injection (pi)) and relatively fast washout in mice (0.09% ID/organ at 60 min pi). The regional brain distribution studies in rats showed high-specific binding ratios at 60 min pi. Maximum regional contrast ratio observed for thalamus/cerebellum was 2.94, followed by 2.62 for hypothalamus/cerebellum. These encouraging results lead us to further explore its derivatives as new imaging agents for the SERT in the brain

  6. Anti-CEA monoclonal antibody: technetium-99m labeling and the validation process of a scintigraphic animal model with a non-cellular antigenic implant.

    Sapienza, Marcelo Tatit; Marques, Fabio Luiz Navarro; Okamoto, Miriam Roseli Yoshie; Hironaka, Fausto Haruki; Buchpiguel, Carlos Alberto

    2002-07-01

    Animal models are currently used to verify the biodistribution of different radiopharmaceuticals before its clinical application in Nuclear Medicine; however, there may be some limitations. The utilization of labelled anti-tumor monoclonal antibodies (MoAb) in experimental models often requires implant of human antigens (usually a cellular implant), which cannot be achieved in immunocompetent animals. Our purpose was to label an anti-CEA MoAb with technetium-99m (99Tc) and to validate a simplified animal model using a noncellular antigenic implant. MoAb was directly labelled with 99mTc, after reduction with 2-mercaptoethanol. Labeling efficiency was checked by ascending chromatography and immunoreactive fraction was measured in plastic wells sensitized with the antigen. Radiopharmaceutical biodistribution was evaluated by dissection and scintigraphy in 5 mice groups; following the subcutaneous administration of Al(OH)3, CEA adsorbed Al(OH)2 and a control group evaluation. Labeling efficiency was 94+/-3%, which showed to be stable for 24 hr, with immunoreactive fraction above 50%. Invasive biodistribution evaluation showed prolonged blood retention, hepatic and renal uptake. A significant increase in uptake was observed in scintigraphic studies of animals with CEA-adsorbed Al(OH)3 implants compared with the other groups (p<0.05). The non-cellular antigenic implant model simplifies the pre-clinical evaluation of labelled MoAb. PMID:12146705

  7. The male reproductive system and the effect of an extract of a medicinal plant (Hypericum perforatum) on the labeling process of blood constituents with technetium-99m

    Santos-Filho, Sebastiao David [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental; Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)]. E-mail: santos-filho@uerj.br; Fonseca, Adenilson de Souza da [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental; Bernardo-Filho, Mario [Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil). Coordenadoria de Pesquisa

    2007-09-15

    Hypericum perforatum (hiperico) is a plant that has been used to treat diseases and also inhibits rat and human vas deferens contractility. In nuclear medicine, stannous chloride (SnCl{sub 2}) is used as a reducing agent to obtain radiopharmaceuticals labeling with technetium-99m. As the SnCl{sub 2} seems to have adverse effects related with the reproductive performance of male rabbits as well as the human consumption of hiperico might affect sexual function. In the present work, consistent results show significant changes on the blood constituents labeled by technetium-99m obtained from young rats under the effect of an hiperico extract as opposed to blood samples equally treated taken from elderly rat. Supposedly, this extract could protect the male reproductive system against action of SnCl{sub 2} at least in young rats. The findings described in this work allow introducing a simple assay to evaluate the action of products that could interfere with the male reproductive system. (author)

  8. Differential labeling of methionine with technetium-99m using chelation and trans-chelation: Can it be used for brain tumor imaging in developing countries

    A protein synthesis marker 11C-methionine-PET was used in differentiating residual post-radiotherapeutic viability and to differentiate the low-grade proliferating glioma with glioblastoma, SPECT facility has wider availability and reports with 201Thallium indicated that it can differentiate recurrence from necrosis. Since 11C and 201Thallium are cyclotron produced isotopes and in underdeveloped / developing countries, non-availability of cyclotron, PET cameras and their costing are the main constraints. With this aim studies were undertaken to label Methionine with technetium-99m for its possible use in brain tumor imaging. The l, methionine, was labeled with Technetium-99m after modifiying certain steps as reported by Tubis et al, and also by transchelating using a weak prochelator glucoheptonate. The labeling efficiencies were in order of 99 % and 97 % with chelating and transchelating mehods. In our studies we found that Tc-99m Methionine SPECT images are comparable with 11C - methionine PET images. The Methionine uptake index was calculated by drawing ROI around the tumor in the slice showing maximum activity and obtaining the counts. To know the background counts a similar ROI was drawn on the contra lateral side/lobe. The ratio of the two was obtained. The ratio as calculated in order of 6.0 and 8.2 for higher grade and low-grade glioma, respectively. The studies conducted so far in 150 patients indicated that this technology could be utilized further to (a) grading gliomas and (b) differentiating glioma from non-tumoral lesions and radiation necrosis.

  9. Protection of plasmid DNA by a Ginkgo biloba extract from the effects of stannous chloride and the action on the labeling of blood elements with technetium-99m

    Moreno S.R.F.

    2004-01-01

    Full Text Available Ginkgo biloba extract (EGb is a phytotherapeutic agent used for the treatment of ischemic and neurological disorders. Because the action of this important extract is not fully known, assays using different biological systems need to be performed. Red blood cells (RBC are labeled with technetium-99m (Tc-99m and used in nuclear medicine. The labeling depends on a reducing agent, usually stannous chloride (SnCl2. We assessed the effect of different concentrations of EGb on the labeling of blood constituents with Tc-99m, as sodium pertechnetate (3.7 MBq, and on the mobility of a plasmid DNA treated with SnCl2 (1.2 µg/ml at room temperature. Blood was incubated with EGb before the addition of SnCl2 and Tc-99m. Plasma (P and RBC were separated and precipitated with trichloroacetic acid, and soluble (SF-P and SF-RBC and insoluble (IF-P and IF-RBC fractions were isolated. The plasmid was incubated with Egb, SnCl2 or EGb plus SnCl2 and agarose gel electrophoresis was performed. The gel was stained with ethidium bromide and the DNA bands were visualized by fluorescence in an ultraviolet transilluminator system. EGb decreased the labeling of RBC, IF-P and IF-RBC. The supercoiled form of the plasmid was modified by treatment with SnCl2 and protected by 40 mg/ml EGb. The effect of EGb on the tested systems may be due to its chelating action with the stannous ions and/or pertechnetate or to the capability to generate reactive oxygen species that could oxidize the stannous ion.

  10. Uncaria tomentosa extract: evaluation of effects on the in vitro and in vivo labeling of blood constituents with technetium-99m

    Silvana Ramos Farias Moreno

    2008-12-01

    Full Text Available The influence (in vivo and in vitro of an Uncaria tomentosa extract (Cats claw on the labeling of red blood cells (RBCs and plasma and cellular proteins with technetium-99m (Tc-99m was evaluated. For the in vivo treatment, animals were treated with Cats claw. For the in vitro treatment, heparinized blood was incubated with Cats claw before the addition of stannous chloride (SnCl2 and Tc-99m. Samples of plasma (P and RBCs were separated and also precipitated with trichloroacetic acid. The soluble and insoluble fractions of P and RBCs were isolated. The analysis of the results of the in vivo study, indicates that there is no significant alteration on the uptake of Tc-99m by the blood constituents, but it significantly decrease (pO objetivo do presente estudo foi avaliar a influência (in vivo e in vitro de um extrato de Uncaria tomentosa (unha de gato na marcação de hemácias e proteínas plasmáticas e celulares com tecnécio-99m (Tc-99m. Para o estudo in vivo, animais foram tratados com um extrato de unha de gato. Para o estudo in vitro, sangue heparinizado foi incubado com o extrato de unha de gato antes da adição de cloreto estanoso (SnCl2 e Tc-99m. Amostras de plasma e células foram separadas e também precipitadas com ácido tricloracético. As frações solúveis e insolúveis foram isoladas. A análise dos resultados do estudo in vivo, indica que não houve alteração significante na captação de Tc-99m pelos constituintes sanguíneos, entretanto, no tratamento in vitro, ocorreu redução significante da marcação de constituintes sanguíneos. Esses efeitos poderiam ser justificados por quelação dos íons estanoso e pertecnetato e bloqueio dos sítios de ligação do Tc-99m.

  11. The effect of an extract from Ganoderma lucidum (reishi) on the labeling of blood constituents with technetium-99m and on the survival of Escherichia coli

    Agostinho, Raquel Terra [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Santos Filho, Sebastiao David; Fonseca, Adenilson de Souza da; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Dept. de Biofisica e Biometria; Missailidis, Sotiris [The Open University, Milton Keynes (United Kingdom). Dept. of Chemistry and Analytical Sciences

    2008-12-15

    This study evaluated effects of an aqueous extract of Ganoderma lucidum (reishi) on the labeling of blood constituents with technetium-99m ({sup 99m}Tc) and on the survival of cultures of Escherichia coli treated with stannous chloride. Blood samples from Wistar rats were treated with reishi extract, radiolabeling procedure was performed, plasma (P), blood cells (BC) and insoluble (IF) and soluble (SF) fractions of P and BC were separated. The radioactivity was counted for the determination of the percentages of radioactivity (%ATI). Cultures of Escherichia coli AB1157 were treated with stannous chloride in the presence and absence of reishi extract. Blood samples and bacterial cultures treated with NaCl 0.9% were used as controls. Data indicated that reishi extract altered significantly (p<0.05) the %ATI of P, BC, IF-P, SF-P, IF-BC and SF-BC, as well as increased the survival of bacterial cultures treated with stannous chloride. Our results suggest that reishi extract could present a redox/chelating action, altering the labeling of blood constituents with {sup 99}mTc and protecting bacterial cultures against oxidative damage induced by stannous chloride. (author)

  12. Effects of chronic sucralose sweetener on the labeling of blood constituents with technetium-99m, morphology of red blood cells and the biodistribution of sodium pertechnetate in rats

    Rocha, Gabrielle de Souza; Pereira, Marcia de Oliveira; Frydman, Jacques Natan Grinapel [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Ciencias da Saude; Benarroz, Monica de Oliveira; Garcia-Pinto, Angelica Beatriz; Fonseca, Adenilson de Souza da; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Instituto de Biologia Roberto Alcantara Gomes. Dept. de Biofisica e Biometria]. E-mail: adenilso@uerj.br; Pereira, Mario Jose [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Fisiologia

    2008-12-15

    This work evaluates effects of the sweetener with sucralose on the labeling of blood constituents with technetium- 99m ({sup 99m}Tc), on the morphology of red blood cells (RBC) and on the biodistribution of sodium pertechnetate in Wistar rats. Animals were treated with sweetener for 8 days. Blood samples were withdrawn and the assay of labeling of blood constituents with {sup 99m}Tc was performed. Blood cells (BC) and plasma (P) were isolated. Aliquots of BC and P were also precipitated, soluble and insoluble fractions separated. The radioactivity in each fraction was counted and percentage of incorporated radioactivity (%ATI) determined. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphology of the RBC was evaluated under optical microscopy. In biodistribution experiments, sodium pertechnetate was administrated, organs and tissues isolated, radioactivity was counted and percentage of incorporated radioactivity per gram (%ATI/g) determined. The data showed no significant alterations in %ATI, morphology of RBC and in %ATI/g in the studied organs. (author)

  13. Effects of chronic sucralose sweetener on the labeling of blood constituents with technetium-99m, morphology of red blood cells and the biodistribution of sodium pertechnetate in rats

    This work evaluates effects of the sweetener with sucralose on the labeling of blood constituents with technetium- 99m (99mTc), on the morphology of red blood cells (RBC) and on the biodistribution of sodium pertechnetate in Wistar rats. Animals were treated with sweetener for 8 days. Blood samples were withdrawn and the assay of labeling of blood constituents with 99mTc was performed. Blood cells (BC) and plasma (P) were isolated. Aliquots of BC and P were also precipitated, soluble and insoluble fractions separated. The radioactivity in each fraction was counted and percentage of incorporated radioactivity (%ATI) determined. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphology of the RBC was evaluated under optical microscopy. In biodistribution experiments, sodium pertechnetate was administrated, organs and tissues isolated, radioactivity was counted and percentage of incorporated radioactivity per gram (%ATI/g) determined. The data showed no significant alterations in %ATI, morphology of RBC and in %ATI/g in the studied organs. (author)

  14. Synthesis and evaluation of a technetium-99m labeled cytotoxic bombesin peptide conjugate for targeting bombesin receptor-expressing tumors

    Conjugation of the cytotoxic drugs to receptor-binding peptides is an attractive approach for the targeted delivery of cytotoxic peptide conjugates to tumor cells. In an attempt to develop an efficient peptide-based radiopharmaceutical for targeting bombesin (BN) receptor-expressing tumors (i.e., breast and prostate), we have prepared by solid-phase peptide synthesis, a novel BN analog derived from the universal sequence of BN and conjugated to a widely characterized antineoplastic agent, methotrexate (MTX). MTX-BN, after radiolabeling with 99mTc via stannous-tartrate exchange, showed a good stability against cysteine and histidine transchelation as well as a high in vitro metabolic stability in human plasma. In vitro cell-binding and internalization on MDA-MB-231, MCF-7, T47-D breast cancer and PC-3 prostate cancer cell lines demonstrated high affinity and specificity of 99mTc-MTX-BN towards both human breast and prostate cancer cells (binding affinities in nanomolar range). In addition, the radioconjugate displayed a significant internalization (values ranged between 19-35%) into the tumor cells. In vivo biodistribution and clearance kinetics in Balb/c mice are characterized by an efficient clearance from the blood and excretion mainly through the renal-urinary pathway with some elimination via the hepatobiliary system. In vivo tumor uptake in nude mice bearing MDA-MB-231 cells was 2.70±0.44% ID/g at 1 h, whereas in nude mice with human epidermoid KB cells the accumulation in the tumor was found to be 1.48±0.31% ID/g at 1 h post injection. The tumor uptake was always higher than in the blood and muscle, with good tumor retention and good tumor-to-blood and tumor-to-muscle ratios. The accumulation/retention in the major organs (i.e., lungs, stomach, liver, intestines, etc.) was low to moderate (99mTc-MTX-BN a potential candidate for the targeted imaging and eventually for radionuclide therapy (when labeled with an appropriate radionuclide) of BN receptor

  15. Synthesis and evaluation of a technetium-99m labeled cytotoxic bombesin peptide conjugate for targeting bombesin receptor-expressing tumors

    Okarvi, Subhani M. [Cyclotron and Radiopharmaceuticals Department, King Faisal Specialist Hospital and Research Centre, MBC-03, PO Box 3354, Riyadh 11211 (Saudi Arabia)], E-mail: sokarvi@kfshrc.edu.sa; Al Jammaz, Ibrahim [Cyclotron and Radiopharmaceuticals Department, King Faisal Specialist Hospital and Research Centre, MBC-03, PO Box 3354, Riyadh 11211 (Saudi Arabia)

    2010-04-15

    concern, particularly for radionuclide therapy. This initial study towards the development of a novel cytotoxic BN conjugate suggest that the combination of favorable in vitro and in vivo properties may render {sup 99m}Tc-MTX-BN a potential candidate for the targeted imaging and eventually for radionuclide therapy (when labeled with an appropriate radionuclide) of BN receptor-positive tumors and deserves further evaluation.

  16. In Vivo Imaging and Tracking of Technetium-99m Labeled Bone Marrow Mesenchymal Stem Cells in Equine Tendinopathy.

    Dudhia, Jayesh; Becerra, Patricia; Valdés, Miguel A; Neves, Francisco; Hartman, Neil G; Smith, Roger K W

    2015-01-01

    Recent advances in the application of bone marrow mesenchymal stem cells (BMMSC) for the treatment of tendon and ligament injuries in the horse suggest improved outcome measures in both experimental and clinical studies. Although the BMMSC are implanted into the tendon lesion in large numbers (usually 10 - 20 million cells), only a relatively small number survive (horses. Tc-99m is a short-lived (t1/2 of 6.01 hr) isotope that emits gamma rays and can be internalized by cells in the presence of the lipophilic compound hexamethylpropyleneamine oxime (HMPAO). These properties make it ideal for use in nuclear medicine clinics for the diagnosis of many different diseases. The fate of the labeled cells can be followed in the short term (up to 36 hr) by gamma scintigraphy to quantify both the number of cells retained in the lesion and distribution of the cells into lungs, thyroid and other organs. This technique is adapted from the labeling of blood leukocytes and could be utilized to image implanted BMMSC in other organs. PMID:26709915

  17. Effect of an Arctium lappa (burdock extract on the labeling of blood constituents with technetium-99m and on the morphology of the red blood cells

    Rosane de Figueiredo Neves

    2007-09-01

    Full Text Available Arctium lappa (burdock has been used to treat inflammatory processes. Blood constituents labeled with technetium-99m (99mTc have been utilized in nuclear medicine. It was evaluated the influence of a burdock extract on the labeling of blood constituents with 99mTc and on the morphometry of red blood cells. Blood samples from Wistar rats were incubated with burdock extract and the radiolabeling procedure was carried out. Plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were separated. The radioactivity in each fraction was counted and the percentages of radioactivity (%ATI were determined. Morphology and morphometric (perimeter/area ratio measurements of red blood cells (RBC were performed. The incubation with burdock extract significantly (pArctium lappa (bardana tem sido utilizada na medicina popular para o tratamento de processos inflamatórios. Constituintes sangüíneos marcados com tecnécio-99m (99mTc são utilizados na medicina nuclear para obtenção de imagens. Neste trabalho foi avaliada a influência de um extrato de bardana na marcação de constituintes sangüíneos com 99mTc e na morfologia de hemácias. Amostras de sangue de ratos Wistar foram incubadas com extrato de bardana e o processo de radiomarcação de constituintes sangüíneos foi realizado. Plasma e células sangüíneas, frações solúvel e insolúvel do plasma e das células sangüíneas foram separadas, a radioatividade em cada fração foi contada e as porcentagens de radioatividade (%ATI foram determinadas. A morfologia e a relação perímetro/área das hemácias foram avaliadas. A incubação de sangue com o extrato de bardana alterou significativamente (p<0.05 a %ATI a distribuição de radioatividade nos compartimentos plasmático e celular. A relação perímetro/área de hemácias, bem como a forma das hemácias também sofreram alterações Modificações na membrana poderiam justificar a diminuição da marcação das c

  18. The male reproductive system and the effect of an extract of a medicinal plant (Hypericum perforatum on the labeling process of blood constituents with technetium-99m

    Sebastião David Santos-Filho

    2007-09-01

    Full Text Available Hypericum perforatum (hiperico is a plant that has been used to treat diseases and also inhibits rat and human vas deferens contractility. In nuclear medicine, stannous chloride (SnCl2 is used as a reducing agent to obtain radiopharmaceuticals labeling with technetium-99m. As the SnCl2 seems to have adverse effects related with the reproductive performance of male rabbits as well as the human consumption of hiperico might affect sexual function. In the present work, consistent results show significant changes on the blood constituents labeled by technetium-99m obtained from young rats under the effect of an hiperico extract as opposed to blood samples equally treated taken from elderly rat.. Supposedly, this extract could protect the male reproductive system against action of SnCl2 at least in young rats. The findings described in this work allow introducing a simple assay to evaluate the action of products that could interfere with the male reproductive system.Hypericum perforatum (hiperico tem sido utilizado para tratar diferentes distúrbios e também inibir a contractilidade do ducto deferente em ratos e em humanos. Na medicina nuclear, o cloreto estanoso (SnCl2 é usado como um agente redutor para obter radiofármacos marcados com tecnécio-99m. Como o SnCl2 parece acarretar efeitos indesejáveis relacionados com o desempenho reprodutivo de coelhos machos e o hiperico pode afetar a função sexual em humanos, o objetivo desse trabalho é apresentar resultados sobre o efeito de um extrato de hiperico na marcação de constituintes sangüíneos com o tecnécio-99m retirados de ratos jovens e idosos. O hiperico parece alterar a marcação de constituintes sangüíneos com tecnécio-99m isolados de sangue de animais jovens. Embora, esse resultado não seja observado em ratos idosos. Provavelmente, o extrato poderia apresentar uma ação protetora para o sistema reprodutivo contra a ação do SnCl2, pelo menos em ratos jovens. Os resultados

  19. Improving the diagnosis of acute appendicitis in children with atypical clinical findings using the technetium-99m hexamethylpropylene amine oxime-labelled white-blood-cell abdomen scan

    Heading AbstractBackground. Diagnosing acute appendicitis in children with equivocal signs and symptoms may be difficult. The usual approach is hospital observation and frequent re-examination. However, many surgeons are reluctant to delay surgery because of the risk of perforation and a negative laparotomy.Objective. To assess and compare the value of the technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO)-labelled white-blood-cell (WBC) abdomen scan in the diagnosis of acute appendicitis in children with atypical clinical presentation.Patients and methods. Fifty children with acute right lower quadrant abdominal pain and possible acute appendicitis, but atypical findings were included. After IV injection of 99mTc-HMPAO-labelled WBCs, serial anterior abdomen scans were obtained using a gamma camera.Results. Thirty-three children underwent surgery, while 17 children were managed conservatively and were followed up for at least 1 month. Four children had false-positive results and one child had a false-negative scan result. The overall sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the scan to diagnose acute appendicitis in children with atypical findings was 96.7, 80.0, 90.0, 87.8 and 94.1%, respectively.Conclusions. The 99mTc-HMPAO WBC abdomen scan is a potential tool for diagnosing acute appendicitis in children with atypical clinical findings. The high sensitivity and negative predictive value allows early discharge from the emergency department to avoid costly observation in hospital and potentially unnecessary surgery in those patients with negative scans. (orig.)

  20. Detection of a local staphylococcal infection in mice with technetium-99m-labeled polyclonal human immunoglobulin

    The purpose of this study was to investigate both the ability of 99mTc-labeled polyclonal human immunoglobulin (HIG) to localize an infection and the modes of action involved in this process. Mice, infected with Staphylococcus aureus ATCC 25923 in a thigh muscle, received HIG intravenously. Scintigrams were made 1, 4, and 24 hr later; subsequently the mice were killed and the activity in several organs and thighs was determined. The radiopharmaceutical demonstrated a time-dependent accumulation at the site of infection. It was found that vascular permeability or Fc binding alone could not account for the mode of action of HIG. Neither the origin of Ig (human versus murine) nor the total amount of protein (0.01-1.0 mg Ig per mouse) affected the target-to-background (T/B) ratios. Ratios were not different for leukocytopenic animals. A correlation (p less than 0.001) was demonstrated between the number of bacteria at the site of infection and the T/B ratio. This was also found after antibiotic treatment (p less than 0.02)

  1. Neutrophil labeling with [{sup 99m}Tc]-technetium stannous colloid is complement receptor 3-mediated and increases the neutrophil priming response to lipopolysaccharide

    Gallagher, Hayley [School of Veterinary and Biomedical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); Ramsay, Stuart C. [School of Medicine, James Cook University, Townsville, Queensland (Australia) and Townsville Nuclear Medicine, Mater Hospital, Townsville, Queensland 4812 (Australia)]. E-mail: stuart.ramsey@jcu.edu.au; Barnes, Jodie [School of Veterinary and Biomedical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); Maggs, Jacqueline [Department of Nuclear Medicine, Townsville Hospital, Townsville, Queensland 4814 (Australia); Cassidy, Nathan [Townsville Nuclear Medicine, Mater Hospital, Townsville, Queensland 4812 (Australia); Ketheesan, Natkunam [School of Veterinary and Biomedical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); School of Medicine, James Cook University, Townsville, Queensland (Australia)

    2006-04-15

    Introduction: [{sup 99m}Tc]-technetium stannous colloid (TcSnC)-labeled white cells are used to image inflammation. Neutrophil labeling with TcSnC is probably phagocytic, but the phagocytic receptor involved is not known. We hypothesised that complement receptor 3 (CR3) plays a key role. Phagocytic labeling could theoretically result in neutrophil activation or priming, affecting the behaviour of labeled cells. Fluorescence-activated cell sorter (FACS) analysis side scatter measurements can assess neutrophil activation and priming. Methods: We tested whether TcSnC neutrophil labeling is CR3-mediated by assessing if neutrophil uptake of TcSnC was inhibited by a monoclonal antibody (mAb) directed at the CD11b component of CR3. We tested if TcSnC-labeled neutrophils show altered activation or priming status, comparing FACS side scatter in labeled and unlabeled neutrophils and examining the effect of lipopolysaccharide (LPS), a known priming agent. Results: Anti-CD11b mAb reduced neutrophil uptake of TcSnC in a dose-dependent fashion. Labeled neutrophils did not show significantly increased side scatter compared to controls. LPS significantly increased side scatter in control cells and labeled neutrophils. However, the increase was significantly greater in labeled neutrophils than unlabeled cells. Conclusions: Neutrophil labeling with TcSnC is related to the function of CR3, a receptor which plays a central role in phagocytosis. TcSnC labeling did not significantly activate or prime neutrophils. However, labeled neutrophils showed a greater priming response to LPS. This could result in labeled neutrophils demonstrating increased adhesion on activated endothelium at sites of infection.

  2. Neutrophil labeling with [99mTc]-technetium stannous colloid is complement receptor 3-mediated and increases the neutrophil priming response to lipopolysaccharide

    Introduction: [99mTc]-technetium stannous colloid (TcSnC)-labeled white cells are used to image inflammation. Neutrophil labeling with TcSnC is probably phagocytic, but the phagocytic receptor involved is not known. We hypothesised that complement receptor 3 (CR3) plays a key role. Phagocytic labeling could theoretically result in neutrophil activation or priming, affecting the behaviour of labeled cells. Fluorescence-activated cell sorter (FACS) analysis side scatter measurements can assess neutrophil activation and priming. Methods: We tested whether TcSnC neutrophil labeling is CR3-mediated by assessing if neutrophil uptake of TcSnC was inhibited by a monoclonal antibody (mAb) directed at the CD11b component of CR3. We tested if TcSnC-labeled neutrophils show altered activation or priming status, comparing FACS side scatter in labeled and unlabeled neutrophils and examining the effect of lipopolysaccharide (LPS), a known priming agent. Results: Anti-CD11b mAb reduced neutrophil uptake of TcSnC in a dose-dependent fashion. Labeled neutrophils did not show significantly increased side scatter compared to controls. LPS significantly increased side scatter in control cells and labeled neutrophils. However, the increase was significantly greater in labeled neutrophils than unlabeled cells. Conclusions: Neutrophil labeling with TcSnC is related to the function of CR3, a receptor which plays a central role in phagocytosis. TcSnC labeling did not significantly activate or prime neutrophils. However, labeled neutrophils showed a greater priming response to LPS. This could result in labeled neutrophils demonstrating increased adhesion on activated endothelium at sites of infection

  3. Development of nano radiopharmaceutical based on Bevacizumab labelled with Technetium-99m for early diagnosis of gastrointestinal stromal tumor; Desenvolvimento de nanorradiofarmaco a base de Bevacizumabe marcado com tecnecio-99m para diagnostico precoce do tumor estromal gastrointestinal

    Braga, Thais Ligiero

    2015-06-01

    The development of new radiopharmaceuticals is an essential activity to improve nuclear medicine, and essential for the early and effective diagnosis of oncological diseases. Among the various possibilities current research in the world, the radiopharmaceuticals to chemotherapeutic base may be the most effective in detecting tumors, particularly Gastrointestinal Stromal Tumor (GIST), the Metastatic Renal Cell Carcinoma and neuroendocrine pancreatic tumors. However, difficulties in directing, as well as adhesion of the radiopharmaceutical in the desired location, are currently the main problems in the early detection and treatment of some of these tumors. Advances in the field of nanotechnology, particularly in recent years, indicate significant contribution to overcoming these obstacles, particularly in the implementation of molecular barriers as well as the functionalization of the nanoparticles, thereby improving targeting by the use of surface nucleotides, and the increased adhesion, which facilitates the release of the drug and therefore increases the chances of early diagnosis and more effective treatment. This study aimed to the production, characterization and evaluation of cytotoxicity, as well as in vivo biodistribution test Bevacizumab nanoparticles labeled with Technetium-99m radionuclide for detection of type GIST tumors. Bevacizumab was encapsulated in the form of nanoparticles by the emulsification method using double poly-acetic acid and polyvinyl alcohol polymers (PLA / PVA) at a concentration of 2% of the monoclonal antibody. The characterization of the nanoparticles was performed by the technique of scanning electron microscopy (SEM). The cytotoxicity assessment was performed by XTT assay with various cell lines of solid tumor cells. The labeling with technetium-99m was done by the direct method, and its yield determined by paper chromatography using paper Whatmam 1 as the stationary phase and acetone as mobile phase. In the biodistribution study

  4. Ventilation/perfusion lung scintigraphy. What is still needed? A review considering technetium-99m-labeled macro-aggregates of albumin

    Lung perfusion scintigraphy (LPS) with technetium-99m-labeled macro-aggregates of albumin (Tc-99m-MAA) is well established in the diagnostic of pulmonary embolism (PE). In the last decade, it was shown that single-photon emission computer tomography (SPECT) acquisition of LPS overcame static scintigraphy. Furthermore, there are rare indications for LPS, such as preoperative quantification of regional lung function prior to lung resection or transplantation, optimization of lung cancer radiation therapy, quantification of right-left shunt, planning of intra-arterial chemotherapy, and several rare indications in pediatrics. Moreover, LPS with Tc-99m-MAA is a safe method with low radiation exposure. PE can also be diagnosed by spiral computer tomography (CT), ultrasound magnetic resonance angiography, or pulmonary angiography (PA, former gold standard). The present review considers all these methods, especially spiral CT, and compares them with LPS with respect to sensitivity and specificity and gives an overview of established and newer publications. It shows that LPS with Tc-99m-MAA represents a diagnostic method of continuing value for PE. In comparison with spiral CT and/or PA, LPS is not to be defeated as mentioned also by the most actual Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II reports. This applies in particular to chronic or recurring embolisms, whereas currently spiral CT may be of greater value for major or life-threatening embolisms. At present, LPS cannot be replaced by other methods in some applications, such as pediatrics or in the quantification of regional pulmonary function in a preoperative context or prior to radiation therapy. LPS still has a place in the diagnostics of PE and is irreplaceable in several rare indications as described earlier. (author)

  5. Role of morphine administration with 99m-technetium-labelled di-isopropyl iminodiacetic acid in the diagnosis of acute cholecystitis

    Patients presenting with a clinical diagnosis suggestive of acute cholecystitis had a 99m-technetium-labelled di-isopropyl iminodiacetic acid (DISIDA) scan. Two groups of patients were investigated. In group 1, 66 patients underwent cholescintigraphy and after 60 minutes morphine was given to all patients whose gallbladders had not filled. The accuracy rate of this procedure was 91%, sensitivity 83%, specificity 97%, positive predictive value 96,2% and negative predictive value 87,5%. In group 2, 97 patients had cholescintigraphy with morphine being administered at the beginning of the procedure. The accuracy rate of this investigation was 97,9%, sensitivity 100%, specificity 96,6%, positive predictive value 95% and negative predictive value 100%. We recommend the early use of morphine in all patients undergoing a DISIDA scan for acute cholecystitis

  6. Conversion to Paradoxical Finding on Technetium-99m-labeled RBC Scintigraphy after Treatment for Secondary Raynaud's Phenomenon

    Chong, Ari; Ha, Jungmin; Song, Hochun; Kim, Jahae; Choi, Soo Jin Na [Chosun Univ. Hospital, Gwangju (Korea, Republic of)

    2013-12-15

    An 18-year-old woman reported that after exposure to cold temperatures her fingers appeared blue and her hands and feet felt cold. Secondary Raynaud's phenomenon (RP) associated with peripheral vascular disease was suspected. Technetium (Tc)-99m-labeled RBC hand scintigraphy after cold change showed decreased blood pool activity in her fingers. The patient's symptoms improved after she received sarpogrelate HCL (200 mg/day) and nifedifine (40 mg/day). Follow-up scintigraphy performed 7 months after the patient started treatment showed paradoxically increased blood pool activity in her fingers after cold challenge. To the best of our knowledge, this is the first case report of a patient with secondary RP showing paradoxical change on scintigraphy after she received medication that improved her symptoms.

  7. Effects of chronic sucralose sweetener on the labeling of blood constituents with technetium-99m, morphology of red blood cells and the biodistribution of sodium pertechnetate in rats

    Gabrielle de Souza Rocha

    2008-12-01

    Full Text Available This work evaluates effects of the sweetener with sucralose on the labeling of blood constituents with technetium-99m (99mTc, on the morphology of red blood cells (RBC and on the biodistribution of sodium pertechnetate in Wistar rats. Animals were treated with sweetener for 8 days. Blood samples were withdrawn and the assay of labeling of blood constituents with 99mTc was performed. Blood cells (BC and plasma (P were isolated. Aliquots of BC and P were also precipitated, soluble and insoluble fractions separated. The radioactivity in each fraction was counted and percentage of incorporated radioactivity (%ATI determined. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphology of the RBC was evaluated under optical microscopy. In biodistribution experiments, sodium pertechnetate was administrated, organs and tissues isolated, radioactivity was counted and percentage of incorporated radioactivity per gram (%ATI/g determined. The data showed no significant alterations in %ATI, morphology of RBC and in %ATI/g in the studied organs.Neste estudo foram avaliados efeitos do adoçante com sucralose na marcação de constituintes sangüíneos com 99mTc, na morfologia de hemácias e na biodistribuição do pertecnetato de sódio em ratos Wistar. Animais foram tratados com adoçante durante 8 dias. Amostras de sangue foram retiradas e a marcação de constituintes sangüíneos com 99mTc foi realizada. Células sangüíneas (CS e plasma (P foram isolados. Alíquotas de CS e P foram precipitadas, frações insolúvel e solúvel foram separadas. A radioatividade em cada fração foi contada e o percentual de radioatividade incorporada (%ATI, determinado. Distensões sangüíneas foram preparadas, fixadas, coradas e análise morfológica, qualitativa e quantitativa, de hemácias foi avaliada sob microscopia óptica. Nos experimentos de biodistribuição, pertecnetato de sódio foi administrado, órgãos e tecidos isolados, a

  8. Biodistribution and biological characteristics of p-[(bis-carboxymethyl) aminomethyl carboxyamino] hippuric acid (Pahida) labelled with technetium-99m. Establishment of pharmacokinetics parameters through compartmental model

    Biologic distribution of p- [(bis-carboxymethylaminomethyl carboxyamino)] hippuric acid (PAHIDA) labeled with sup(99m)Tc in Wistar rats, showed a selective renal uptake among the other organs and tissues. The compound is predominantly eliminated by urinary tract, with small enterohepatic percent of excretion Chromatographic analysis of urine showed the product and possible metabolites. PAHIDA- sup(99m)Tc blood clearance is relatively rapid and a good percent is transported by plasmatic proteins. The percent binding to the erythrocytes is significant after one hour, this is due probably to hydrolysed technetium. The extrapolation of the plasmatic curve denoted the existence of three exponentials, suggesting a model with three compartments: central or intravascular and two peripherics or extravasculars - rapid and slow exchange (retention). Exponential's half life and the transfer constant (k) among the compartments were determined. The compound retention was reaffirmed by whole body determination. The decomposition of the curve in two exponentials allowed to assess the component's half-life. The compartmental model proposed in agreement with the experimental results, showed the complex retention that may be related the binding with the blood components, the possibility of renal metabolization or a structural impediment in the interaction with the tubular cells receptors. (author)

  9. Technetium-99m-diethyl-IDA instant kit

    A formulation of stannous-diethyl-IDA freeze-dried kit, containing 50 mg diethyl-IDA and 0.4 mg hydrated stannous chloride, to be labelled with technetium was developed for hepatobiliary scintigraphy. The organ distribution data of 99mTc-diethyl-IDA in mice for 60 min post injection were satisfactory. The radiopharmaceutical exhibits rapid blood clearance, great hepatic clearance and very short hepatocyte transit time. Uptake of the radiopharmaceutical was highest in mouse liver and intestine. The renal uptake of the HB agent in mice is relatively low. Blood clearance data showed that the HB agent is rapidly cleared. (author) 20 refs.; 4 tabs

  10. The effect of an extract from Ganoderma lucidum (reishi on the labeling of blood constituents with technetium-99m and on the survival of Escherichia coli

    Raquel Terra Agostinho

    2008-12-01

    Full Text Available This study evaluated effects of an aqueous extract of Ganoderma lucidum (reishi on the labeling of blood constituents with technetium-99m (99mTc and on the survival of cultures of Escherichia coli treated with stannous chloride. Blood samples from Wistar rats were treated with reishi extract, radiolabeling procedure was performed, plasma (P, blood cells (BC and insoluble (IF and soluble (SF fractions of P and BC were separated. The radioactivity was counted for the determination of the percentages of radioactivity (%ATI. Cultures of Escherichia coli AB1157 were treated with stannous chloride in the presence and absence of reishi extract. Blood samples and bacterial cultures treated with NaCl 0.9% were used as controls. Data indicated that reishi extract altered significantly (pEste estudo avaliou efeitos de um extrato de Ganoderma lucidum (reishi na marcação de constituintes sangüíneos com tecnécio-99m (99mTc e na sobrevivência de culturas de Escherichia coli tratadas com cloreto estanoso. Amostras de sangue de ratos Wistar foram tratadas com extrato de reishi, o procedimento de radiomarcação foi realizado, plasma (P, células sangüíneas (CS e frações insolúvel (FI e solúvel (FS de P e CS foram separadas e a radioatividade foi contada para determinação das porcentagens de radioatividade (%ATI. Culturas de Escherichia coli AB1157 foram tratadas com cloreto estanoso na presença e ausência do extrato de reishi. Amostras de sangue e culturas bacterianas tratadas com NaCl 0.9% foram usadas como controles. Dados indicaram que o extrato de reishi alterou significativamente (p<0,05 a %ATI de P, CS, FI-P, FS-P, FI-CS e FS-CS, bem como, aumentou a sobrevivência de culturas bacterianas tratadas com cloreto estanoso. Nossos resultados sugerem que o extrato de reishi poderia apresentar ação redox/quelante alterando a marcação de constituintes sangüíneos com 99mTc e protegendo culturas bacterianas contra lesões oxidativas induzidas

  11. Effect of an extract of Artemisia vulgaris L. (Mugwort on the in vitro labeling of red blood cells and plasma proteins with technetium-99m

    Danielle Amorim Terra

    2007-09-01

    Full Text Available The aim of this work was to evaluate the effect of an extract of the Artemisia vulgaris L. (mugwort on the labeling of blood constituents with technetium-99m (99mTc. Blood samples from Wistar rats were incubated with a mugwort extract and the radiolabeling of blood constituents was carried out. Plasma and blood cells were separated by centrifugation. Aliquots of plasma and blood cells were also precipitated with trichloroacetic acid and centrifuged to isolate soluble and insoluble fractions of plasma and blood cells. Radioactivity in each fraction was counted and the percentages of radioactivity (%ATI was calculated. Mugwort extract decreased significantly (pO objetivo desse trabalho foi avaliar o efeito da Artemisia vulgaris L.(artemisa na marcação dos constituintes sangüíneos com tecnécio-99m (99mTc. Amostras de sangue obtidas de ratos Wistar foram incubadas com um extrato de artemisa e o processo de radiomarcação dos constituintes sangüíneos foi realizado. Plasma e células sangüíneas foram isoladas por centrifugação. Alíquotas de plasma e células sangüíneas foram também precipitadas com ácido tricloroacético para isolamento de frações solúvel e insolúvel. A radiatividade em cada fração foi contada e as porcentagens de radioatividade (%ATI foram calculadas. O extrato de artemisa diminuiu significantemente (p<0,05 a %ATI nas células sanguíneas e nas proteínas celulares. A análise dos resultados indicou que o extrato de artemisa apresentaria substâncias que interferir no transporte de íons estanoso e/ou pertecnetato através da membrana do eritrócito alterando a marcação das células sangúineas com 99mTc.

  12. Gentc99m, computational system for the technetium-99m generator

    The technetium-99m generator is one of the main products of the PPR, as the continuity of the technetium-99m generator production is important for supporting the development of nuclear medicine. GENTC99M has been made for computational for the technetium-99m generator and includes data processing, documentation and information GENTC99M is also very useful in quality control application especially for the determinations of yield and radionuclidic impurities which consume much time. microsoft visual basic for MS-DOS and visual basic for windows have been used for making GENTC99M. Microsoft visual basic has several features that make it an ideal development language for both MS-DOS and Microsoft Windows. These features not only increase productivity, they also provide all the tools and hooks needed to develop some very sophisticated applications. for a production centre like PPR, GENTC99M is very useful to support the data processing, documentation and information system of the technetium-99m generator and it can also be modified for other products

  13. Diagnosis of deep vein thrombosis of the lower limbs with scintigraphy of red blood cells labelled with 99m technetium

    The clinical diagnosis of leg deep vein thrombosis (DVT) is notoriously unreliable. It must be supplemented by objective techniques which all have drawbacks. 99mTc-RBC venography also has its limitations, yet it is a simple, safe, and useful test for diagnosing DVT of the lower limb. When done carefully, it is a rewarding procedure with good sensitivity and specificity for the condition both in the calf and ilio-femoral regions. Blood pool venography is readily accessible to all nuclear medicine department for the diagnosis of thrombophlebitis and also the follow-up of treated patients

  14. [99mTc]Technetium labelled PnAo-azomycin glucuronides: a novel class of imaging markers of tissue hypoxia

    Azomycin glucuronate was coupled to a PnAO ligand to create azomycin-based ligands that would form water-soluble 99mTc-azomycin complexes for imaging hypoxic tissue. 1-β-D-(2-Nitroimidazolyl)glucuronic acid, 1, was synthesized by coupling 2-nitroimidazole with 1-α-bromo-2,3,4-tri-O-acetyl-6-methyl glucuronate, followed by deprotection. Reaction of 1 with 6-methyl-6-methylamino-HMPnAO (Pn-44) in the presence of BOP reagent in anhydrous dimethyl sulfoxide afforded the PnAO-glucuronides 5 and 6. Compound 5 was isolated in three rotomeric forms. Biological evaluation of 7 (99mTc-5) indicated selective binding to hypoxic EMT-6 cells, and cytotoxicity to fibroblasts and HeLa, sk24, sk23, and g361 cancer cell lines, at an IC20 <2.5 μg/ml. In vivo biodistribution of two formulations of 7 in Balb/c mice with EMT-6 tumor produced diverse results, with one formulation showing no tumor preference, and the other providing a tumor/blood ratio of 2.3 at 4 h post-injection. The latter formulation delineated tumor, large intestine and liver in scintigraphic images

  15. Human polyclonal immunoglobulin labelled with technetium-99m via NHS-MAG3: a comparison of radiochemical behavior and biological efficacy with other labelling methods

    The aim of this study was to evaluate the radiochemical behavior, biological distribution, and localization in infection sites in mice of a human polyclonal immunoglobulin (HIG) labelled with 99mTc by a novel MAG3-labelling method. The resulting [99mTc]MAG3-HIG was compared with [99mTc]HIG preparations radiolabelled directly via 2-mercaptoethanol (2-Me) or stannous ion (Sn) reduction and indirectly via 2-iminothiolane (2-Im) conjugation. All preparations showed similar UV and radioactivity HPLC profile to that of native HIG except for 2-Im-HIG, which showed aggregates. The stabilities of the label to challenge with cysteine were similar for all the preparations. By nondenaturing SDS-PAGE, all preparations other than MAG3-HIG showed evidence of lower molecular weight fragments. The tissue distribution 4 and 24 h after intravenous administration of the four preparations were compared in mice previously administered with an isolate of Staphylococcus aureus in one thigh. The pharmacokinetics varied among the different preparations. When prepared via 2-Me, Sn, and 2-Im, both blood clearance and urinary excretion were faster than that of labelled MAG3-HIG. The absolute uptake in the infected thigh at 24 h was significantly higher for HIG labelled via MAG3 and 2-Me vs. the remaining methods. The infected thigh/normal thigh radioactivity ratios were similar at both time points for labelled HIG prepared via 2-Me, 2-Im, and NHS-MAG3 methods but was significantly lower at 24 h for HIG prepared via Sn. The radioactive HPLC profiles of serum at 4 and 24 h were similar to that of the radiolabelled injectates. Based on these data we conclude that each radiolabelled HIG preparation studied showed increased localization in infectious foci although [99mTc]MAG3-HIG showed superior radiochemical and biological characteristics under the conditions of this investigation

  16. Technetium-99m radiopharmaceuticals for in vivo diagnostics

    Đokić Divna Đ.

    2005-01-01

    Full Text Available Technetiiim-99m is an ideal radionuclide with optimum decay characteristics. It can be obtained in sterile, pyrogen-free and carrier-free condition, as sodium pertechnetate (Na99mTcO4, from 99Mo/99Tc generator. Because of its six-hour physical half-life and monochromatic 140 keV photons free of -radiation, administration of small amounts of 99mTc solution is possible, without a significant radiation damage to the patient. Technetium eluted from the 99Mo/99mTc generator is in the highest oxidation form (+7. It can be used for diagnostic purposes alone, but it is often used for labeling different organic and inorganic compounds. As it is unreactive, reduction with a chemical reductant, (+1, (+3 and (+5 oxidation are necessary before use. Nowadays almost 80% of radiopharmaceuticals are based on 99mTc. Radiopharmaceuticals. Radiopharmaceuticals are radionuclides or radioactive compounds used in diagnosis and therapy of human diseases. A pharmaceutical is chosen based on its localization in the organ, or its participation in its physiological function. Radiation emitted from a radionuclide is detected by a radiation detector. The ability to incorporate available radionuclides into tracer molecules has been the main goal in developing radiopharmaceuticals. As radionuclides with nuclear characteristics used as either diagnostic or therapeutic radiopharmaceuticals, are predominantly metals, they can be designed as metal essential, whereby biological distribution is determined by coordination compound, or metal tagged, in which case the properties of the carrier molecule (ligand system determine the biological distribution. This paper reviews the development of 99mTc-radiopharmaceuticals. .

  17. Technetium-99m as alternative to produce somatostatin-labeled derivatives: comparative biodistribution evaluation with {sup 111}In-DTPA-octreotide

    Melo, Ivani B.; Buchpiguel, Carlos Alberto, E-mail: ivani@hcnet.usp.br [Universidade de Sao Paulo (USP/LIM43), SP (Brazil). Centro de Medicina Nuclear. Departamento de Radiologia; Ueda, Laura T.; Araujo, Elaine B. de; Muramoto, Emiko; Barboza, Marycel F. de; Mengatti, Jair; Silva, Constancia P.G. da, E-mail: ebaraujo@ipen.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Radiofarmacia

    2008-07-01

    Synthetic somatostatin (SST) analogues have been used in the preparation of receptor-specific radiopharmaceuticals for diagnostic and therapy of neuroendocrine (NE) tumors. {sup 111}In-DTPA-Octreotide (OctreoScan®) has found useful for imaging a range of tumors, including NE cancer, carcinoide and lymphoma. Unfortunately, {sup 111}In is a high-cost cyclotron produced radioisotope with gamma emission not so suitable for scintigraphic images and for dosimetry like {sup 99m}Tc. This work studied the labeling conditions with {sup 99m}Tc and biological distribution in Swiss mice of two SST analogs (HYNIC-Tyr{sup 3}-Octreotide and HYNICTyr{sup 3}- Octreotate) and compared the biodistribution pattern with {sup 111}In-DTPA-Octreotide. {sup 99}mTc-HYNIC-Tyr{sup 3}- Octreotate ({sup 99m}Tc-HYNIC-TATE) and {sup 99m}Tc-HYNIC-Tyr{sup 3}-Octreotide ({sup 99m}Tc-HYNIC-OCT) were produced by labeling conditions using tricine and EDDA as coligands. {sup 111}In-DTPA-Octreotide ({sup 111}In-DTPA-OCT) was produced by labeling DTPA-Octreotide with {sup 111}InCl{sub 3} (Nordion). Radiochemical purity of labeled preparations was determined by ITLC-SG. Biological distribution studies were performed after injection of radiopharmaceuticals on Swiss mice. Labeling procedures resulted on high radiochemical yield for all three preparations and the labeled products presented high in vitro stability. Biological distribution studies evidenced similar general biodistribution of {sup 99m}Tc-labeled peptides when compared with indium-labeled peptide with fast blood clearance and elimination by urinary tract. Kidneys uptake of {sup 99}mTc-HYNIC-TATE are similar to {sup 111}In-DTPA-Octreotide, and both are significantly higher than {sup 99}mTc-HYNIC-OCT. All labeled peptides presented similar uptake on liver, but the retention in time at intestines, particularly at large intestine, was more expressive for {sup 111}In-labeled peptide. The %ID of {sup 99m}Tc-HYNIC-OCT and {sup 99m}Tc-HYNIC-TATE in

  18. 99m Technetium pyrophosphate myocardium scintigraphy. First results

    99m technetium pyrophosphate myocardium scintigraphy is a very recent examination technique. This work gives the results obtained on 61 patients. As a vector of the isotope, pyrophosphate has the advantage over polyphosphate of a fast bone uptake there it should be stressed that a 90 minute pause is necessary between the intraveinous injection of the isotope and the photographic recording so that the reading is not troubled by the labelled intracardiac blood pool image, an image quality criterion being the estimation of a good costal fixation which in fact appears sooner or later according to the subject. The role of pyrophosphate, chelator of calcium in fixation of the isotope on the myocardium, could be explained by the fast appearance of 'dense bodies', made up of calcium hydroxyapathice crystals, in the mitochondria of myocardium cells having undergone an irreversible necrotic process. The choice of 99 m technetium is based on its ease of use: 6 hour half-life, high-energy pure gamma emission at 140 keV. The fixed image studied under two incidences, front and left anterior oblique, is obtained from mobile images given by the scintillation camera used in connection with a data processing system. Several facts are underlined, explaining the disadvantages, advantages and indications of the method

  19. Carbonyl iron (magnetic) suspensions labelled with technetium-99m. A potential radiopharmaceutical for improved radionuclide angiography and systemic blood flow determinations

    Carbonyl iron particles 3μm in diameter can be conveniently labelled with technetium-99m at specific activities of at least 4mCi/mg of iron. Labelling is achieved by suspending the particles in 99Tcsup(m)-pertechnetate in isotonic saline and using heat. This labelling process is more than 99% efficient. The suspension is maintained by use of a suspending agent and an ultrasonic bath. The preparation is potentially useful for both angiography and blood-flow determinations. 99Tcsup(m) carbonyl iron particle suspension, in the absence of a strong magnetic field, localizes in the reticuloendothelial system of the liver and spleen. Some activity is also retained by the lungs and kidneys. When the radiolabelled particles are intravenously injected into a rabbit's ear and a powerful, hand-held, permanent magnet (1000G at 5mm) is placed adjacent to the abdominal aorta, the radioactive particles passing by the magnet are partially trapped. Removal of the magnet releases the particles. Magnetic fields of 1000G also produce aggregation of the radiolabelled iron particles. When the kidney is placed within such a magnetic field and then the particles are injected intravenously, there is extensive trapping of the aggregated particles in the precapillary vessels. If the field is rapidly removed and a ''degaussing'' (alternating) magnetic field introduced, the aggregation process is reversed and there is extensive clearing of the particles from the kidney. The radiolabelled particles can thus be used for blood flow determinations in a manner analogous to radiolabelled albumin aggregates. Unlike albumin aggregates, however, radiolabelled iron particles can be injected intravenously and will pass through the pulmonary circulation. Also, the precapillary occlusive process is at least partially reversible. (author)

  20. Effects of acute and long-term bronchodilator treatment on regional lung function in asthma assessed with krypton-81m and technetium-99m-labelled macroaggregates.

    Sovijärvi, A R; Pöyhönen, L.; Kellomäki, L; Muittari, A

    1982-01-01

    We have investigated the effect of acute and long-term bronchodilator treatment on the distribution of ventilation and perfusion in 15 asthmatics using a gamma camera, krypton-81m (for ventilation) and technetium-99m macroaggregate (for perfusion). Individual peak expiratory flow (PEF) values before bronchodilation were slightly or moderately below the predicted values. The simultaneous ventilation images (analysed visually) showed areas of delayed ventilation in all patients (mean distributi...

  1. Clearance of technetium-99m-labeled DTPA in hyperthyroidism without clinical evidence of lung disease, and relation to pulmonary function

    The mechanisms of dyspnea and exercise intolerance have not been fully elucidated. We aimed to investigate the clearance rate of technetium-99m diethyltriaminepentaaceticacid (Tc-99m DTPA) from lungs in hyperthyroid patients without clinical evidence of lung disease and to explore the interactions between their Tc-99m DTPA radioaerosol lung scintigraphy, spirometric measurements, and the levels of thyroid hormones. We studied 19 hyperthyroid patients and 16 sex- and age-matched controls. Thyroid hormone levels were assessed. Spirometric lung function tests, diffusing capacity of the lung for carbon monoxide (DLCO) and the clearance rate of Tc-99m DTPA were performed in all participants. Ratio of DLCO value to the alveolar ventilation (DLCO/VA) and the means of half-time (T1/2) of Tc-99m DTPA clearance rate, which were used to evaluate alveolar-capillary membrane permeability, were calculated. There were no statistical differences between spirometric parameters (vital capacity (VC), force vital capacity (FVC), one second forced expiratory volume (FEV1)/FVC, mean forced expiratory flow during the middle of FVC (FEF 25-75)) of the two groups (p>0.05). Although the mean FEV1 level was significantly lower in the hyperthyroid patients than the control subjects (p1 was only less than 80 percent of the predicted value. No significant difference in the means of DLCO, DLCO/VA or T1/2 values of Tc-99m DTPA clearance was observed between the two groups (p>0.05). In hyperthyroid patients, there was a positive relation between DLCO/VA, DLCO/VA% and T1/2 values of Tc-99m DTPA clearance (p1/2 values of Tc-99m DTPA clearance in hyperthyroid group (p>0.05). We conclude that increased thyroid hormones have no effect on permeability of alveolar-capillary membrane in hyperthyroid patients. (author)

  2. The retention mechanism of technetium-99m-HM-PAO

    Neirinckx, R D; Burke, J F; Harrison, R C; Forster, A M; Andersen, A R; Lassen, N A

    1988-01-01

    Preparations of d,l- and meso-hexamethylpropyleneamine oxime (HM-PAO) labeled with technetium-99m were added to rat brain homogenates diluted with phosphate buffer (1:10). The conversion of d,l-HM-PAO to hydrophilic forms took place with an initial rate constant of 0.12 min-1. Incubation of the...... chromatographic characteristics as found in the brain homogenates. The rate constant for the conversion reaction of d,l-HM-PAO in GSH aqueous solution was 208 and 317 L/mol/min in two different assay systems and for meso-HM-PAO the values were 14.7 and 23.2 L/mol/min, respectively. Rat brain has a GSH...... correspondence of values supports the notion that GSH may be important for the in vivo conversion of 99mTc-labeled HM-PAO to hydrophilic forms and may be the mechanism of trapping in brain and other cells. A kinetic model for the trapping of d,l- and meso-HM-PAO in tissue is developed that is based on data of...

  3. Stabilization of marked hexametazima with technetium 99-metastables (99mTc) with chloride of cobalt hexahidratado, for the labelling of leukocytes

    Presently study you work with hexametilpropilen amino oxima (HM-PAO), radiopharmaceuticals of labelling leucocytes marking it with technetium 99 recently acquired of the second elution of a generator of molybdenum technetium adding chloride of cobalt hexahidratado in different concentrations, as stabilizing agent in order to settling down if it prolongs the useful life of this expensive radiopharmaceuticals for but of minutes. For it one carries out the determination from the purity radiochemical to the 5,60,120 and 180 minutes after the labelled and the labelling of leukocytes is made with quality control of the cells after the labelling compared against a control

  4. Drug interaction with radiopharmaceuticals: effect on the labeling of red blood cells with technetium-99m and on the bioavailability of radiopharmaceuticals

    Maria Luisa Gomes

    2002-09-01

    Full Text Available The evidence that natural and synthetic drugs can affect radiolabeling or bioavailability of radiopharmaceuticals in setting of nuclear medicine clinic is already known. However, this drug interaction with radiopharmaceuticals (DIR is not completely understood. Several authors have described the effect of drugs on the labeling of blood elements with technetium-99m (99mTc and on the biodistribution of radiopharmaceuticals. When the DIR is known, if desirable or undesirable, the natural consequence is a correct diagnosis. However, when it is unknown, it is undesirable and the consequences are the possibility of misdiagnosis and/or the repetition of the examination with an increase of radiation dose to the patient. The possible explanation to the appearance of DIR are (a radiopharmaceutical modification, (b alteration of the labeling efficiency of the radiopharmaceutical, (c modification of the target, (d modification of no target and/or the (e alteration of the binding of the radiopharmaceutical on the blood proteins. The effect of drugs on the labeling of blood elements with 99mTc might be explained by (i a direct inhibition (chelating action of the stannous and pertechnetate ions, (ii damage induced in the plasma membrane, (iii competition of the cited ions for the same binding sites, (iv possible generation of reactive oxygen species that could oxidize the stannous ion and/or (v direct oxidation of the stannous ion. In conclusion, the development of biological models to study the DIR is highly relevant.A evidência de que drogas naturais ou sintéticas podem afetar a radiomarcação ou a biodisponibilidade de radiofármacos nos procedimentos de medicina nuclear já é bem conhecida. Entretanto, essa interação de droga com radiofármacos (IDR não está completamente compreendida. Vários autores têm descrito o efeito de drogas na marcação de elementos sanguíneos com tecnécio-99m (99mTce na biodistribuição de radiofármacos. Quando a

  5. Biological evaluation of a technetium-99m-labeled integrated tropane-BAT and its piperidine congener as potential dopamine transporter imaging agents

    Kieffer, Davy M. [Laboratory of Radiopharmaceutical Chemistry, University of Leuven, UZ Gasthuisberg, B-3000 Leuven (Belgium); Vanbilloen, Hubert P. [Radiopharmacy, UZ Gasthuisberg, B-3000 Leuven (Belgium); Cleynhens, Bernard J. [Radiopharmacy, UZ Gasthuisberg, B-3000 Leuven (Belgium); Terwinghe, Christelle Y. [Radiopharmacy, UZ Gasthuisberg, B-3000 Leuven (Belgium); Mortelmans, Luc [Nuclear Medicine, UZ Gasthuisberg, B-3000 Leuven (Belgium); Bormans, Guy M. [Laboratory of Radiopharmaceutical Chemistry, University of Leuven, UZ Gasthuisberg, B-3000 Leuven (Belgium); Verbruggen, Alfons M. [Laboratory of Radiopharmaceutical Chemistry, University of Leuven, UZ Gasthuisberg, B-3000 Leuven (Belgium)]. E-mail: alfons.verbruggen@uz.kuleuven.ac.be

    2006-01-15

    Introduction: Recently, we have reported modification of {sup 99m}Tc-TRODAT-1 by integrating the N2S2 metal chelating unit and the tropane skeleton. Results of a preliminary biodistribution study in rats were promising with respect to brain uptake. The present report deals with the further biological characterization of the {sup 99m}Tc-labelled integrated TRODAT derivatives ({sup 99m}Tc-TropaBAT and {sup 99m}Tc-norchloro-TropaBAT) and with the synthesis and biological evaluation of a novel {sup 99m}Tc-labelled piperidine-based derivative ({sup 99m}Tc-PipBAT). Methods: Biodistribution of all radiolabelled complexes was studied in normal mice. A more detailed ex vivo intracerebral distribution study of the two {sup 99m}Tc-TropaBAT complexes was additionally performed in normal rats. Autoradiography of brain sections of normal mice (with or without pretreatment with FP-{beta}-CIT or haloperidol) and rats was performed. Affinity for the dopamine transporter (DAT) was also assessed in vitro in the presence or absence of cocaine. Results: Both {sup 99m}Tc-TropaBAT complexes show a slightly higher brain uptake than {sup 99m}Tc-TRODAT-1, but the striatum/cerebellum activity ratio is less favourable. Nevertheless, significant striatal uptake was detected after ex vivo autoradiography, but this uptake was also observed after pretreatment with FP-{beta}-CIT. Unexpectedly, no striatal uptake was detected after in vitro incubation of mouse brain sections with the tracer agents. For {sup 99m}Tc-PipBAT, neither brain uptake nor in vitro striatal uptake was found. Conclusion: Both {sup 99m}Tc-TropaBAT complexes exhibit similar diffusion into brain as {sup 99m}Tc-TRODAT-1, and ex vivo autoradiography shows significant striatal uptake. However, the inferior striatum/cerebellum activity ratio, the striatal uptake in mice pretreated with FP-{beta}-CIT or haloperidol, and the lack of striatal uptake during in vitro incubation prove that the DAT is not targeted. Brain uptake disappears

  6. Bleeding rates necessary for detecting acute gastrointestinal bleeding with technetium-99m-labeled red blood cells in an experimental model

    Proponents of [/sup 99m/Tc]sulfur colloid for GI bleeding studies argue that, although labeled red blood cells are useful for intermittent bleeding, they are not capable of detecting low bleeding rates. Studies of dogs with experimental GI bleeding have indicated bleeding rates of 0.05 ml/min can be detected with [/sup 99m/Tc]sulfur colloid. Since similar data in the dog model were unavailable for /sup 99m/Tc-labeled red blood cells, we undertook this study. To simulate lower GI bleeding, catheters were inserted into the bowel lumen. Each dog's blood was labeled with /sup 99m/Tc using an in vitro technique. Venous blood was then withdrawn and re-infused into the lumen of the bowel using a Harvard pump. Fourteen dogs were studied, ten receiving a bleeding rate from 4.6-0.02 ml/min in the descending colon and four with proximal jejunal bleeds of 0.20-0.02 ml/min. Bleeding rates of 4.6-0.2 ml/min were detected within 10 min in the colon and bleeding rates as low as 0.04 ml/min were seen by 55 min. Slower bleeding rates were not detected. Similar findings were noted for proximal jejunal bleeds. Based on the time of appearance, a minimum volume of approximately 2-3 ml labeled blood was necessary to detect bleeding. We conclude that /sup 99m/Tc-labeled RBCs are sensitive for low bleeding rates in the dog model. The rates are comparable to those described for [/sup 99m/Tc]sulfur colloid in this experimental setting. The time of appearance of activity is related to the bleeding rate

  7. Biomedical tracers: technetium-99 m complexing sulfur polydentate ligands

    Cyclic and acyclic tetra sulfur ligands have been synthesized and some of them have been labelled with technetium-99m. These works have two different aims: 1- Development of methods permitting to obtain easily potential technetium complexing sulfur polydentate chelates. 2- Research of positive and neutral complexes of this metal likely to replace thalium-201 in the coronary flow estimation and [TcO-HMPAO] sup 0 complex in the cerebral scintigraphy, respectively. In this work, first, different ways for obtaining dithioetherdithiols and cyclic tetrathioethers containing functional groups have been carried out, then complexation of the core of nitrutechnetium (TcN) sup 2+ at tracers scale, by dithioetherdithiols, using exchange reaction with [sup 9 sup 9 sup m TcNCl sub 4 ] sup - ion complex or sup 99 sup m TcN Cl sub 2 [P(CH sub 2 CH sub 2 CN) sub 3 ] sub 2 has been studied. Finally, biological distribution in swiss mouse of these technetiated complexes has been studied. 135 refs., 30 figs., 13 tabs. (F.M.)

  8. Evaluation of radiolabeling of annexin A5 with technetium-99m: influence of the labeling methods on physico-chemical and biological properties of the compounds

    Annexin A5 (ANXA5) is an intracellular human protein of 36 kDa with high affinity for membrane-bound phosphatidylserine that is selectively exposed on the surface of cells undergoing apoptosis. Apoptosis is important in normal physiology and innumerous pathologic states. Clinical applications for ANXA5 imaging are being developed in oncology, organ transplantation and cardiovascular diseases. Many strategies to radiolabel the protein have been described, including direct labeling, derivatization through a bifunctional chelating agent (BFC), production of mutated protein or peptide analogs. Several 99mTc-labeling techniques have been reported using different cores, including [Tc=O]+3, [Tc]HYNIC, [Tc≡N]+2 and [Tc(CO3)]+1. In this study, we evaluated the influence of 99mTc cores on biological behavior and physico-chemical properties of radiolabeled annexin. Radiolabeling procedure using [Tc≡N]+2 core was a two-step procedure including the reaction of 99mTcO4 - with SDH in the presence of SnCl2 and PDTA to obtain the intermediate 99mTcN-SDH, and successive addition of ANXA5. The results obtained were not satisfactory, despite the high efficiency in the production of the intermediate. The [Tc=O]+3 core was produced using the ethylene dicysteine (EC) as BFC. TSTU was employed in the derivatization to produce the corresponding hydroxysuccinimide ester. Different ANXA5:EC ratios were studied and all labeling conditions resulted in high radiochemical yield but with differences in lipophilicity, stability, biological distribution and affinity for apoptotic cells. The HYNIC-ANXA5 also produced the labeled protein with high radiochemical yield. The stability of the radiolabeled ANXA5 was evaluated after storing at room temperature, at 2 - 8 degree C and in human serum at 37 degree C. The analysis of these results showed that the 99mTc-EC-ANXA5 (ratio 10-2) was the most stable compound in all the studied conditions. Partition coefficient assay resulted in lower

  9. Technetium-99m Radiopharmaceuticals for Monitoring Drug Resistance. Chapter 12

    Resistance to chemotherapy constitutes a major obstacle to cancer cures. Cellular mechanisms of resistance involve efflux pumps, P-glycoprotein (Pgp), the product of the MDR1 gene and the related membrane glycoprotein, multidrug resistance associated protein 1 (MRP1). Multidrug resistant cell lines overexpressing Pgp are resistant to a structurally and functionally diverse group of chemotherapeutic agents. Many of these drugs tend to be lipophilic and positively charged at neutral pH. This suggested the application of the two lipophilic cationic 99mTc radiopharmaceuticals currently used for myocardial perfusion, 99mTc-MIBI and 99mTc-Tetrofosmin. Efforts were also made to develop specific 99mTc labelled substrates for Pgp based on lipophilic cationic 99mTc complexes. A large number of studies indicated that 99mTc-MIBI, 99mTc-Tetrofosmin and some related 99mTc compounds are substrates for Pgp. However, it remains uncertain whether these 99mTc labelled compounds are substrates for MRP1. Thus, both 99mTc-MIBI and 99mTc-Tetrofosmin would be general probes of transporter mediated multidrug resistance in tumour cells. (author)

  10. Leukocyte labeling with isonitrile complexes of Tc-99m

    Leukocyte labelling with Tc-99m may result in a useful method for the detection and localization of active inflammatory processes in patients, particularly in the pediatric population. Previous studies qin this laboratory have shown that hexakis(alkylisonitrile)technetium(I) complexes readily label V79 lung fibroblasts in vitro, and this work is now being extended to isolated human white blood cells (WBC). Two lipophilic water-soluble technetium cations, the t-butyl [Tc-99m(TBI)] and cyclohexyl [Tc-99m(CHI)] analogs, were prepared essentially ligand-free at no-carrier-added levels in aqueous media and introduced in 10% propylene glycol/90% normal saline solution to WBC at room temperature. The cells were isolated from whole blood via sedimentation, centrifugation, and hypotonic hemolysis of the red blood cells. The labeling yield was studied as a function of incubation time (10-45 min), amount of activity (0.35-8.0 mCi), and total WBC (2.5 x 10/sup 7/-1.3 x 10/sup 8/). After 10 min incubation using 10/sup 8/ cells, the initial uptake of Tc-99m(TBI) was 40%, of which 50% remained bound after one saline wash. By contrast, the labeling efficiency with Tc-99m(CHI) was 85%, with 90% of the label still bound after washing. The labeling yield was unrelated to activity levels of incubation time, but was proportional to the number of WBC present. The entire process could be complemented in approximately one hour. The labeling yields with Tc-99m-(CHI) are comparable to those now obtained with the clinically available In-111 oxine

  11. Preparation of a generator of technetium-99m

    Practical description is given of equipment and operations necessary in the preparation of an isotopic generator of technetium-99m. The preparation and application of the active solution and throughly washed of the chromatographic column have been studied in order to allow molibdenum-99 to be adsorbed on a small band, and the solution of tectium-99m to be eluted with high efficiency and purity. The equipment and accesories used are easy and safety to manage, simplifying operations to be carried out with the active product, eliminating the sterile environment in the shielded cell, and facilitating the preparation of the solution of technetium-99m in sterile and pyrogen-free conditions.(author)

  12. Effect of a peel passion fruit flour (Passiflora edulis f. flavicarpa) extract on the labeling of blood constituents with technetium-99m and on the morphology of red blood cells

    Passiflora edulis f. flavicarpa (maracuja) is a fruit consumed in Brazil and worldwide. Blood constituents labeled with technetium-99m (99mTc) are used in nuclear medicine. The effect of P. flavicarpa extract on the radiolabeling of blood constituents and on red blood cells morphology was evaluated. Blood samples from Wistar rats was incubated with P. flavicarpa extract. After that, the labeling of blood constituents with 99mTc was carried out. Samples of plasma and blood cells were precipitated with trichloroacetic acid to isolate the soluble and insoluble fractions of plasma and blood cells. The radioactivity in each fractions was counted and the percentage of radioactivity was determined. Blood smears were also prepared to morphological evaluation and perimeter/area ratio determination. P. flavicarpa extract altered (p99mTc on plasma proteins and the perimeter/area ratio of red blood cells. Substances present in P. flavicarpa extract could affect the labeling of blood constituents with 99mTc acting in specific targets as membrane of red blood cells. (author)

  13. Effect of a peel passion fruit flour (Passiflora edulis f. flavicarpa) extract on the labeling of blood constituents with technetium-99m and on the morphology of red blood cells

    Rebello, Bernardo Machado; Moreno, Silvana Ramos Farias; Ribeiro, Camila Godinho; Neves, Rosane de Figueiredo; Fonseca, Adenilson de Souza da; Bernardo-Filho, Mario; Medeiros, Aldo da Cunha [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Programa de Pos-graduacao em Ciencias da Saude]. E-mail: rebellobm@uol.com.br; Caldas, Luis Querino de Araujo [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Ciencias Medicas

    2007-09-15

    Passiflora edulis f. flavicarpa (maracuja) is a fruit consumed in Brazil and worldwide. Blood constituents labeled with technetium-99m (99mTc) are used in nuclear medicine. The effect of P. flavicarpa extract on the radiolabeling of blood constituents and on red blood cells morphology was evaluated. Blood samples from Wistar rats was incubated with P. flavicarpa extract. After that, the labeling of blood constituents with 99mTc was carried out. Samples of plasma and blood cells were precipitated with trichloroacetic acid to isolate the soluble and insoluble fractions of plasma and blood cells. The radioactivity in each fractions was counted and the percentage of radioactivity was determined. Blood smears were also prepared to morphological evaluation and perimeter/area ratio determination. P. flavicarpa extract altered (p<0.05) the fixation of {sup 99m}Tc on plasma proteins and the perimeter/area ratio of red blood cells. Substances present in P. flavicarpa extract could affect the labeling of blood constituents with {sup 99m}Tc acting in specific targets as membrane of red blood cells. (author)

  14. Study of the viability of technetium-99m labeling of whole antimyosin antibody and its fragment: development of radiopharmaceutical for cardiac survey

    In the acute myocardium infarction, the myocytes cell membrane loses its integrity, allowing the influx of extracellular macromolecules such as circulating antibody into the damaged cell. The use of the specific antibodies against cardiac myosin labeled with 99mTc allows to determine the localization and extension of myocardial infarction. The purpose of this work was to study the viability of labeling of the antimyosin monoclonal antibody and its fragment F(ab')2 with 99mTc. Because of the high cost of antimyosin antibody, others antibodies were used to optimize the methodology and the best condition was used for antimyosin antibody. The intact antibody was cleaved by pepsin to produce F(ab')2 fragment. The F(ab')2 and the intact antibody were reduced by treatment with Dithiothreitol (DTT) and 2-Mercaptoethanol (2-ME) and labeled with 99mTc by direct method. Different concentrations of reductant, mixing conditions and incubation times were studied. In the standard condition, incubation at molar ratio 1:1000 (antibody:reducing agent) at room temperature for 30 minutes with continuous rotation (850 rpm), 13.28 - SH groups were formed per molecule. It was studied the influence of p H, of the concentration of stannous chloride (Sn2+) and incubation time in the labeling condition. The better radiochemical yield (90.06 +- 1.53%) was obtained using 2.5 μg of Sn2+ in p H 4.5 for 60 minutes. The labeling of the fragment F(ab')2 did not present satisfactory results because of the low yield of the digestion. After purification by PD-10, the biodistribution study was performed and showed that the intact antimyosin antibody labeled with 99mTc presented fast kinetic compatible with the biodistribution of an intact antibody labeled with 99mTc. Scintigraphy image of the animal with myocardial infarction was obtained and compared with the image of a normal animal. The studies allow to conclude that the use of fragment F(ab')2 are not viable, but the use of the labeled antimyosin

  15. Technetium-99m-labeled Arg-Gly-Asp-conjugated alpha-melanocyte stimulating hormone hybrid peptides for human melanoma imaging

    Introduction: The purpose of this study was to examine whether 99mTc-labeled Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone (α-MSH) hybrid peptide targeting both melanocortin-1 (MC1) and αvβ3 integrin receptors was superior in melanoma targeting to 99mTc-labeled α-MSH or RGD peptide targeting only the MC1 or αvβ3 integrin receptor. Methods: RGD-Lys-(Arg11)CCMSH, RAD-Lys-(Arg11)CCMSH and RGD-Lys-(Arg11)CCMSHscramble were designed to target both MC1 and αvβ3 integrin receptors, MC1 receptor only and αvβ3 integrin receptor only, respectively. The MC1 or αvβ3 integrin receptor binding affinities of three peptides were determined in M21 human melanoma cells. The melanoma targeting properties of 99mTc-labeled RGD-Lys-(Arg11)CCMSH, RAD-Lys-(Arg11)CCMSH and RGD-Lys-(Arg11)CCMSHscramble were determined in M21 human melanoma-xenografted nude mice. Meanwhile, the melanoma uptake of 99mTc-RGD-Lys-(Arg11)CCMSH was blocked with various non-radiolabeled peptides in M21 melanoma xenografts. Results: RGD-Lys-(Arg11)CCMSH displayed 2.0 and 403 nM binding affinities to both MC1 and αvβ3 integrin receptors, whereas RAD-Lys-(Arg11)CCMSH or RGD-Lys-(Arg11)CCMSHscramble lost their αvβ3 integrin receptor binding affinity by greater than 248-fold or MC1 receptor binding affinity by more than 100-fold, respectively. The melanoma uptake of 99mTc-RGD-Lys-(Arg11)CCMSH was 2.49 and 2.24 times (P 99mTc-RAD-Lys-(Arg11)CCMSH and 99mTc-RGD-Lys-(Arg11)CCMSHscramble at 2 h post-injection, respectively. Either RGD or (Arg11)CCMSH peptide co-injection could block 42% and 57% of the tumor uptake of 99mTc-RGD-Lys-(Arg11)CCMSH, whereas the coinjection of RGD+(Arg11)CCMSH peptide mixture could block 66% of the tumor uptake of 99mTc-RGD-Lys-(Arg11)CCMSH. Conclusions: Targeting both MC1 and αvβ3 integrin receptors enhanced the melanoma uptake of 99mTc-RGD-Lys-(Arg11)CCMSH in M21 human melanoma xenografts. Flank M21 human melanoma tumors were clearly visualized by single

  16. 99mTc: Labeling Chemistry and Labeled Compounds

    Alberto, R.; Abram, U.

    This chapter reviews the radiopharmaceutical chemistry of technetium related to the synthesis of perfusion agents and to the labeling of receptor-binding biomolecules. To understand the limitations of technetium chemistry imposed by future application of the complexes in nuclear medicine, an introductory section analyzes the compulsory requirements to be considered when facing the incentive of introducing a novel radiopharmaceutical into the market. Requirements from chemistry, routine application, and market are discussed. In a subsequent section, commercially available 99mTc-based radiopharmaceuticals are treated. It covers the complexes in use for imaging the most important target organs such as heart, brain, or kidney. The commercially available radiopharmaceuticals fulfill the requirements outlined earlier and are discussed with this background. In a following section, the properties and perspectives of the different generations of radiopharmaceuticals are described in a general way, covering characteristics for perfusion agents and for receptor-specific molecules. Technetium chemistry for the synthesis of perfusion agents and the different labeling approaches for target-specific biomolecules are summarized. The review comprises a general introduction to the common approaches currently in use, employing the N x S4-x , [3+1] and 2-hydrazino-nicotinicacid (HYNIC) method as well as more recent strategies such as the carbonyl and the TcN approach. Direct labeling without the need of a bifunctional chelator is briefly reviewed as well. More particularly, recent developments in the labeling of concrete targeting molecules, the second generation of radiopharmaceuticals, is then discussed and prominent examples with antibodies/peptides, neuroreceptor targeting small molecules, myocardial imaging agents, vitamins, thymidine, and complexes relevant to multidrug resistance are given. In addition, a new approach toward peptide drug development is described. The section

  17. Radioimmunoscintigraphy of colorectal carcinoma using technetium-99m-labeled, totally human monoclonal antibody 88BV59H21-2.

    Gulec, S A; Serafini, A N; Moffat, F L; Vargas-Cuba, R D; Sfakianakis, G N; Franceschi, D; Crichton, V Z; Subramanian, R; Klein, J L; De Jager, R L

    1995-12-01

    Radioimmunoscintigraphy (RIS) using human monoclonal antibodies offers the important clinical advantage of repeated imaging over murine monoclonal antibodies by eliminating the cross-species antibody response. This article reports a Phase I-II clinical trial with Tc-99m-labeled, totally human monoclonal antibody 88BV59H21-2 in patients with colorectal carcinoma. The study population consisted of 34 patients with colorectal cancer (20 men and 14 women; age range, 44-81 years). Patients were administered 5-10 mg antibody labeled with 21-41 mCi Tc-99m by the i.v. route and imaged at 3-10 and 16-24 h after infusion using planar and single-photon emission computed tomographic (CT) techniques. Pathological confirmation was obtained in 25 patients who underwent surgery. Human antihuman antibody (HAHA) titers were checked prior to and 1 and 3 months after the infusion. RIS with Tc-99m-labeled 88BV59H21-2 revealed a better detection rate in the abdomen-pelvis region compared with axial CT. The combined use of both modalities increased the sensitivity in both the liver and abdomen-pelvis regions. Ten patients developed mild adverse reactions (chills and fever). No HAHA response was detected in this series. Tc-99m-labeled human monoclonal antibody 88BV59H21-2 RIS shows promise as a useful diagnostic modality in patients with colorectal cancer. RIS alone or in combination with CT is more sensitive than CT in detecting tumor within the abdomen and pelvis. Repeated RIS studies may be possible, due to the lack of a HAHA response. PMID:7493345

  18. A sup(99m)Tc-labelled peptide

    This invention concerns a new peptide labelled with sup(99m)Tc. It also covers the process for preparing this labelled peptide as well as the therapeutical mixture containing it in conjunction with a physiologically acceptable excipient. One of the purpose of the invention is to suggest a new vector providing a faster localization of the sup(99m)Tc, particularly with respect to the pituitary gland and the other organs so that the 99m isotope of the technetium reaches the organs to be visualized in under 10 minutes and so that the total administering and recording time by means of a scintillation camera connected to a computer and a fast printer is not more than 20 minutes. The invention was achieved through the choice of a particular peptide that is found in the amino-acid sequences of natural hormones (ACTH, MSH)

  19. Influence of different chelators (HYNIC, MAG3 and DTPA) on tumor cell accumulation and mouse biodistribution of technetium-99m labeled to antisense DNA

    We have shown recently that cell accumulation in culture of antisense DNA is strongly influenced by the presence of a 99mTc-MAG3 group for radiolabeling. We have now compared the in vitro and mouse in vivo behavior of 99mTc when radiolabeled to one antisense phosphorothioate DNA by three different methods. The 18-mer antisense DNA against the RIα subunit of PKA was conjugated via a primary amine on the 5'-end with the NHS esters of HYNIC and MAG3 and by the cyclic anhydride of DTPA. Surface plasmon resonance measurements revealed that the association rate constant for hybridization was unchanged for all three chelators as compared with that of the native DNA. Size exclusion HPLC showed rapid and quantitative protein binding for all three chelators upon incubation of labeled DNAs in 37 C serum and cell culture medium. However, in each case, radiolabeled and intact oligonucleotide was still detectable after 24 h. Cellular uptake was tested in an RIα mRNA-positive cancer cell line. The order of cellular accumulation of 99mTc was DTPA>HYNIC(tricine)>MAG3, with the differences increasing with time between 4 and 24 h. The rate of 99mTc egress from cells was found to be MAG3>HYNIC>DTPA, which may explain the order of cellular accumulation. The biodistribution in normal mice was heavily influenced by the labeling method and followed a pattern similar to that seen previously by us for peptides labeled with the same chelators. In conclusion, although these studies concerned only one antisense DNA in one cell line, the results suggest that the success of antisense imaging may depend, in part, on the method of radiolabeling. (orig.)

  20. Preparation and evaluation of third generation technetium-99m radiopharmaceuticals

    The preparation and evaluation of three different 99mTc labelled peptides as third generation radiopharmaceuticals is presented. Lys3-Bombesin ([Lys3]BN), ubiquicidin 29-41(UBI 29-41) and Tyr3-octreotide (TOC) were prepared as instant kit formulations to be labelled by direct or indirect methods with 99mTc in order to evaluate in vivo prostate malignancies, infection processes and lung cancer respectively. Radiochemical purity of >93% was obtained. Also, high in vitro and in vivo stabilities and preservation of the molecular recognition were observed. It is demonstrated that 99mTc-EDDA/ HYNIC-[Lys3]BN detects GRP receptor positive tumours in mice, 99mTc-UBI 29-41 detects infection foci in humans and 99mTc-EDDA/HYNIC-TOC is useful in patients with lung cancer. (author)

  1. Assessment of the effect of Bacopa monnieri (L.) Wettst. extract on the labeling of blood elements with technetium-99m and on the morphology of red blood cells Avaliação do efeito do extrato de Bacopa monnieri (L.) Wettst. na marcação de elementos sanguíneos com tecnécio-99m e na morfologia de células vermelhas do sangue

    Kakali De; Susmita Chandra; Mridula Misra

    2009-01-01

    Bacopa monnieri (L.) Wettst. (BM), a traditional Ayurvedic medicine, used for centuries as a memory enhancing, anti-inflammatory, antipyretic, sedative and antiepileptic agent. BM extract have been extensively investigated by several authors for their neuropharmacological effects. In nuclear medicine, red blood cells (RBC) labeled with technetium-99m (99mTc) have several clinical applications. However, data have demonstrated that synthetic or natural drugs could modify the labeling of RBC wit...

  2. Technetium-99m nitrido radiopharmaceuticals with unprecedented biological properties

    Adriano Duatti

    2002-09-01

    Full Text Available The chemical methods for the production of technetium-99m radiopharmaceuticals containing a terminal TcºN triple bond have been established more than a decade ago. From that time, the chemistry of nitrido Tc-99m complexes has provided a highly efficient tool for the design and preparation of novel classes of diagnostic agents, and a number of potentially useful radiopharmaceuticals have been discovered. In particular, nitrido technetium-99m tracers have been developed for heart perfusion imaging. In this short review, the chemical and biological properties of the neutral myocardial perfusion tracer bis(N-ethoxy, N-ethyl-dithiocarbamato nitrido Tc-99m (TcN-NOEt will be summarized along with the preparation and preliminary biological evaluation of the first class of monocationic nitrido technetium-99m radiopharmaceuticals exhibiting improved biodistribution properties closer to those expected for an ideal perfusion imaging agent.Os métodos químicos para produção de radiofármacos marcados com tecnécio-99m contendo a ligação tripla terminal TcºN foram estabelecidos há mais de uma década. Desde esta época, a química dos complexos nitridos marcados com 99mTc tem sido uma ferramenta altamente eficiente para o desenho e preparo de novas classes de agentes para diagnóstico e, foi descoberto um número de radiofarmacos potencialmente úteis. Nesta pequena revisão, as propriedades biológicas e químicas do traçador para perfusão miocárdica neutra, o bis(N-etoxi, N-etil-ditiocarbamato nitrido 99mTc (TcN-NOEt, serão resumidas junto com o preparo e avaliação biológica preliminar da primeira classe de radiofármacos nitrido monocatiônico marcado com tecnécio-99m que exibe melhores propriedades em relação à biodistribuição, mais próximas daquelas esperadas para um agente perfusor ideal para imagens.

  3. Technetium-99m pertechnetate - a tracer for radiolabelling antibody for inflammation detection

    The polyclonal antibody, Human Immunoglobulin G (HlgG) was reduced by using 2-mercaptoethanol with molar ratio of 1000:1 (i.e. mercaptoethanol:antibody). The reduction of the antibody, was carried out for 30 minutes at room temperature. The reduced antibody was purified by using Sephadex G-25 fine column. The antibody kit for the detection of inflammation was prepared aseptically in Class 1 Laminar Flow cabinet. The kit passed the sterility test. Upon reconstitution of the antibody kit with sodium pertechnetate-99m (99mTc) solution, the labelling efficiency obtained was more than 95%. This preparation was stable up to 24-hour stored at room temperature. Gamma camera scans showed the accumulation of technetium-99m labelled antibody (99mTc-HIgG) at the turpentine-induced inflammation of female Sprague-Dawley rats. This indicated the possibility of using 99mTc-HIgG for inflammation detection. (author)

  4. Technetium 99m pertechnetate thyroid scintigraphy: Congenital hypothyroid screening

    Wells, R.G.; Sty, J.R.; Duck, S.C.

    1986-07-01

    Technetium 99m pertechnetate thyroid scans were performed on 57 infants referred for evaluation of suspected congenital hypothyroidism. Thyroid anatomy may be characterized by four general types, based on the scintigraphic findings: (1) normal size and location. (2) ectopic location. (3) no detectable thyroid activity. (4) normal location with increased size or uptake. There are diverse etiologies of congential hypothyroidism. Correlation of thyroid scintigraphy with blood T4 and TSH levels allows specific etiological diagnosis in the majority of cases of congential hypothyroidism.

  5. Technetium-99m pentavalent dimercaptosuccinic acid imaging for pituitary adenomas

    The authors performed scintigraphy using 99mTc(V)-DMSA (Technetium-99m pentavalent dimercaptosuccinic acid) on patients with pituitary adenomas. Three non-functioning (100%), 2 GH-secreting (67%), 4 PRL-secreting (80%), and zero ACTH-secreting (0%) adenomas concentrated the 99mTc(V)-DMSA, but all 5 of the non-adenomatous lesions and 1 normal pituitary gland did not. There was no significant relationship between tumor-to-background ratios and tumor sizes, or the serum hormone level. The 99mTc(V)-DMSA scintigraphy showed an overall sensitivity of 69% (9/13) in detecting pituitary adenomas, which increased to 82% for non-functioning, GH-secreting and PRL-secreting adenomas. In conclusions, 99mTc(V)-DMSA was found to be a suitable radiotracer for detecting pituitary adenomas. But further studies are necessary to define the processes that concentrate 99mTc(V)-DMSA and their role in pituitary adenomas. (author)

  6. The impact of technetium-99m-radiopharmaceuticals' design on their biological behavior

    The coordination has a great and not always predictable impact on the in-vivo behaviour of the small molecule into which the technetium-bearing chelate units is integrated. The different valence state of technetium in the complexes with some ligands changes the properties of these complexes, such as physico-chemical parameters and biological behaviour. The change of their biological behaviour has a great impact on quality of imaging study and on radiation dose to the patient. The results of the labelling of DPD and EHIDA with 99mTc(I) and their biological behaviour, in comparison with the same one for 99mTc(III)-DPD and 99mTc(III)-EHIDA complexes, confirmed that different oxidation state of 99mTc make possible forming variety of complexes with quite a different and unexpected biological behaviour. (author)

  7. Leukocyte-technetium-99m uptake in Crohn s disease:Does it show subclinical disease?

    Luciene; G; Mota; Luiz; GV; Coelho; Carlos; JR; Simal; Maria; LA; Ferrari; Clodomiro; Toledo; Josep; Martin-Comin; Simone; OF; Diniz; Valbert; N; Cardoso

    2010-01-01

    AIM:To evaluate inflammatory activity in patients with Crohn's disease (CD) using technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) granulocyte scintigraphy.METHODS: Twenty patients (7 male and 13 female) with CD and five healthy volunteers were selected for 99mTc-HMPAO granulocyte scintigraphy. The Crohn's Disease Activity Index (CDAI), blood tests and C-reactive protein (CRP) of each patient were performed 7 d before the scintigraphic images. The leukocytes were labeled according to the Internat...

  8. Migration pathways of hypodermically injected technetium-99 m in dogs

    Hypodermic injection of technetium-99 m (99mTC-pertechnetate) at points of low electrical resistance give rise to rapid, longitudinal, and progressive diffusion of the radioactive tracer. We assessed the effect of cutaneous incisions that did not intersect the migration trajectory of 99mTc-pertechnetate and the re-establishment of pathways after the suture of incisions that intersected the migration trajectory. Linear and rapid migration of 99mTc-pertechnetate was not altered or prevented by incisions that did not intersect the migration pathway. Different patterns of 99mTc-pertechnetate spread were found when incisions intersected the radioactive pathways until restoration of the normal migration pathway observed in undamaged skin occurred. In all experiments in which migration of 99mTc-pertechnetate was observed, lavage of surgical wounds was followed by disappearance of the 99mTc-pertechnetate migration observed around the suture. Linear migration of the tracer was not observed when the incision was left uncovered, filled with petroleum jelly, or with a solid silicone sheet, but it was seen when non-sutured incisions were filled with transonic or silicone gel or covered with a solid silicone sheet parallel to the cutaneous plane. These data show that after a cutaneous incision that intersected the diffusion trajectory of the radioactive tracer, linear migration of 99mTc-pertechnetate hypodermically injected at points of low electrical resistance was restored before healing of the cutaneous incision and was independent of incisions made on the skin not overlying the radioactive pathway. A mechanism similar to that of capillary electrophoresis is suggested to explain the hypodermic diffusion of inert particles through specific and constant linear pathways. (orig.)

  9. Technetium-99m hexamethyl propylene amine oxime-labeled leukocyte scintigraphy at three different times in active ulcerative colitis. Comparison with colonoscopy and clinico-biochemical parameters in the assessment of disease extension and severity

    In this study, our objective was to define the usefulness of technetium-99m hexamethyl propylene amine oxime (Tc-99m HMPAO)-labeled leukocyte scintigraphy at three different time points in the assessment of disease extension and severity in patients with active ulcerative colitis (UC). Twenty-one consecutive patients (10 women, 11 men; mean age 42.4±12 years) with active UC were prospectively studied. All patients were diagnosed by colonoscopy and histopathology prior to inclusion. Scintigraphy was performed at 1 h, 2 h, and 4 h after Tc-99m HMPAO-labeled leukocyte injection. Clinic-biochemical activity score, total colonoscopic activity score, and total scintigraphic activity score at 1 h, 2 h, and 4 h were calculated for each patient. Sensitivity, specificity, and accuracy values of Tc-99m HMPAO-labeled leukocyte scintigraphy were calculated as follows, respectively: 1 h imaging 86%, 73%, and 83%; 2 h imaging 89%, 74%, and 86%; 4 h imaging 90%, 58%, and 83% in the detection of active inflammatory segments. Even though no statistically significant difference was found between 1 h, 2 h, and 4 h imaging with respect to the sensitivity, specificity of labeled leukocyte scintigraphy, the largest area under the curve value was found for 2 h imaging. Tc-99m HMPAO-labeled leukocyte scintigraphy has been found to be correlated well with colonoscopy in the assessment of both the extension and severity of UC. We recommend 2 h scintigraphic imaging because it provides the largest area under the curve value and decreases the number of false-positive results. (author)

  10. Lyophilized kits of diamino dithiol compounds for labelling with {sup 99m}-technetium. Pharmacokinetics studies and distribution compartmental models of the related complexes; Conjuntos de reativos liofilizados de compostos diaminoditiolicos para marcacao com tecnecio-99m. Estudo farmacocinetico e elaboracao de modelos compartimentalizados dos respectivos complexos

    Araujo, Elaine Bortoleti de

    1995-07-01

    The present work reflects the clinical interest for labelling diamino dithiol compounds with technetium-99m. Both chosen compounds, L,L-Ethylene dicysteine (L,L-EC) and L,L-Ethylene dicysteine diethyl esther (L,L-ECD) were obtained with relative good yield and characterized by IR and NMR. The study of labelling conditions with technetium-99m showed the influence of the type and mass of reducing agent as well as the pH on the formation of complexes with desired biological characteristics. Radiochemical purity was determined by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Lyophilised kits of L,L-EC and L,L-ECD for labelling with {sup 99m}Tc were obtained, with stability superior to 120 days, when stored under refrigeration, enabling the kits marketing. The ideal formulation of the kits as well as the use of liquid nitrogen in the freezing process, determined the lyophilization success. Distribution biological studies of the {sup 99m}Tc complexes were performed on mice by invasive method and on bigger animals by scintigraphic evaluation. Biological distribution studies of the complex {sup 99m}Tc-L,L-EC showed fast blood clearance, with the elimination of about 90% of the administered dose after 60 minutes, almost exclusively by the urinary system. The biological distribution results were adjusted to a three compartmental distribution model, as expected for a radiopharmaceutical designed to renal dynamic studies, with tubular elimination. The complex interaction with renal tubular receptors is related with structural characteristics of the compound, more specifically with the presence and location of polar groups. In comparison with {sup 99m}Tc-L,L-EC, biological studies of the complex {sup 99m}Tc -L,L-ECD showed different distribution aspects, despite some structural similarities. The presence of ethyl groups confers to the complex neutrality and lipophilicity. It cross the intact blood brain barrier and is retained in the brain

  11. Guarana (Paullinia cupana) effect on radiolabelling of erythrocytes with Technetium-99m

    The labelling of red blood cells (RBC) with technetium-99m (Tc-99m) have been used for many studies in nuclear medicine. This labeling procedure depends on a reducing agent and stannous chloride is normally used for this purpose. Many factors, including drug therapy, can affect the biodistribution of radiopharmaceuticals, such factors many lead to poor organ visualization, requirement to repeat the examination procedure or even misdiagnosis. Guarana (Paullinia cupana) is commonly used in popular medicine. Here, we investigate if guarana is capable to alter the labeling of RBC with Tc-99m and to modify the radioactivity binding to plasma proteins and cellular constituents from insoluble and soluble fractions. The results were obtained with blood samples from Wistar rats with heparine and incubated with different guarana solutions. The percentage of radioactivity (% rad) from BC and P were calculated. The distribution of radioactivity in P and BC showed that the uptake of Tc-99m decreased significantly in all concentrations. (author)

  12. Technetium-99m carboxymethylcellulose: A newly developed fibre marker for gastric emptying studies

    We report a study of technetium-99m-labelled carboxymethyl-cellulose (99mTc-CMC) as a newly developed non-digestible marker of the solid phase of gastric contents. The radiosynthesis is simple and shows a high labelling efficiency. In vitro and in vivo experiments demonstrated stability of the marker in the gastrointestinal tract during the process of gastric emptying. The gastric half-emptying time in ten healthy volunteers of both sexes was 105±17 min (mean±SD). This rate of gastric emptying is similar to that of non-digestible solid-phase markers such as in vivo labelled 99mTc-chicken liver or radio-iodinated cellulose. In comparison with digestible solid-phase markers such as 99mTc-labelled pancake or 99mTc-cooked egg, gastric emptying of 99mTc-CMC occurred more slowly, confirming the expected behaviour of a non-digestible solid-phase marker. We conclude that 99mTc-CMC has the advantage of a simple and rapid labelling procedure and may be useful for clinical studies of gastric emptying. (orig.)

  13. Effects of acute and long-term bronchodilator treatment on regional lung function in asthma assessed with krypton-81m and technetium-99m-labelled macroaggregates

    An investigation has been made of the effects of acute and long-term bronchodilator treatment on the distribution of ventilation and perfusion in 15 asthmatics using a gamma camera, krypton-81 m (for ventilation) and technetium-99m macroaggregate (for perfusion). Individual peak expiratory flow (PEF) values before bronchodilation were slightly or moderately below the predicted values. The simultaneous ventilation images (analysed visually) showed areas of delayed ventilation in all patients (mean distribution score on 3-point scale 2.1). After isoprenaline inhalation (240 μg) the mean PEF increased by 24%, but the distribution of ventilation remained virtually unchanged in all patients (mean score 2.0). Simultaneously defects in perfusion could be seen in all patients (mean score 1.5). After intensive treatment, when the mean PEF increased by a further 29%, the distribution scores of ventilation and perfusion fell to 0.8 and 0.9, respectively. The results indicate that, without intensive and long-term treatment, appreciable inequality of ventilation and perfusion are usual consequences of asthma; and suggest that although larger airways are dilated by isoprenaline inhalations residual bronchial obstruction may still remain in some smaller airways, maintaining uneven distribution. Perfusion disturbances seem to be secondary to changes in regional ventilation. (author)

  14. Effect of the extract of Ricinus communis L. on the osmotic fragility, labeling of red blood cells with Technetium-99m and morphology of the cells

    Kristiana Cerqueira Mousinho

    2008-12-01

    Full Text Available The aim of this study was to evaluate the influence of the proteic extract of R. communis on the cell physiology by the osmotic fragility, labeling of the blood elements with the 99mTc and cell morphology. To evaluate the osmotic fragility, the blood samples of the Wistar rats were incubated with the concentrations of R. communis and with the solutions of NaCl (0.4; 0.7; 0.9%. In the labeling of the blood elements procedure, the rat blood was treated with a solution of Tc-99m and TCA at 5%, determining the rate of radioactivity (%ATI in the plasma (P and in the red blood cells (RBC. The soluble and insoluble fractions of the plasma were also evaluated. The cells morphology submitted to the extract was evaluated by the optical microscopy (x40. The results indicated that the rate of the hemolysis increased in the presence of 0.125 mg/mL of the extract. There was a decay of 49.69% in the rate of ATI in the insoluble fraction of the cells, with the morphological alterations in the red blood cells. These results suggested that the extract changed the capability of binding of the red blood cells due to the stannous ion oxidation, modifying the cells structure.Produtos naturais são usados freqüentemente por muitas pessoas no tratamento do câncer. O Ricinus communis L é uma Euforbiaceae que apresenta propriedades laxativas, purgativas e antitumorais. O objetivo deste trabalho é estudar a influência da fração protéica do extrato hidroalcoólico de R. communis L. na fisiologia celular através da fragilidade osmótica, da marcação de elementos sanguíneo com 99mTc e da morfologia celular. Para avaliar a fragilidade osmótica, amostras de sangue de ratos Wistar foram incubadas com concentrações de R. communis e com soluções de NaCl (0,4; 0,7; 0,9%. No procedimento de marcação de elementos sanguíneos, as amostras de sangue foram tratadas com solução de Tc-99m e TCA à 5%, determinando o percentual de radioatividade (%ATI no plasma (P e

  15. Radiolabelling of monoclonal antibodies with technetium-99 m via metallothionein

    Metallothionein (MT), a small cysteine-rich protein, was used as a bifunctional chelating agent in the radiolabelling of monoclonal antibodies with Tc-99m. The efficiency of the conjugation reaction of MT with antibodies (Ab) was found as 58%. The yield of radiolabelling of Tc-99m to MT-Ab by reduction method was higher than 90%, while the unspecific radiolabelling occurred less than 10%. The Tc-99m-MT-Ab has proven to be satisfactory stable in Vitro in the presence of a couple of strong chelating agents. The preliminary biological experimental results in tumor-bearing nude mice indicated that the Tc-99m-labelled anti-colorectal carcinoma monoclonal antibody 2C10 had strong affinity toward tumor and was stable in vivo

  16. Assessment of the effect of Mentha crispa L. (hortela) extract on the labeling of red blood cells and plasma proteins with technetium-99m

    Santos-Filho, Sebastiao D. [UNIFOA - Centro Universitario de Volta Redonda, RJ (Brazil). Dept. de Biofisica; Dire, Glaucio L.; Lima, Elaine [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria; Pereira, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Anatomia; Bernardo-Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria]|[Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil). Centro de Pesquisa Basica

    2002-07-01

    We have investigated the possibility of M. Crispa L. extract being capable to alter the labeling of blood elements with 99mTc. Blood was incubated with M. Crispa L. extract. Stannous chloride solution and Tc-99m, as sodium pertechnetate, were added. Blood was centrifuged and plasma (P) and blood cells (BC) were isolated. Samples of P and BC were also precipitated, centrifuged and insoluble (IF) and soluble (SF) separated. The percentage of radioactivity (% ATI) in BC, IF-P and IF-BC was calculated. Histological evaluations were performed and the morphology of the red blood cells was observed under optical microscopy showing important morphological alterations on the shape of the RBC treated with 6.25% M. Crispa L. extract. The % ATI decreased: on BC from 97.3 {+-} 1.92 to 60.0 {+-} 2.44; on IF-P from 74.8 {+-} 3.78 to 9.99 {+-} 3.61; on IF-BC from 88.6 {+-} 5.41 to 58.4 {+-} 11.55. The substances of the M. Crispa L. extract could increase the valence of these stannous (+2) ions to stannic (+4) and this fact would decrease the % ATI on blood elements and indicates the possible presence of oxidant agents in the M. Crispa L. extract. (author)

  17. Assessment of the effect of Mentha crispa L. (hortela) extract on the labeling of red blood cells and plasma proteins with technetium-99m

    We have investigated the possibility of M. Crispa L. extract being capable to alter the labeling of blood elements with 99mTc. Blood was incubated with M. Crispa L. extract. Stannous chloride solution and Tc-99m, as sodium pertechnetate, were added. Blood was centrifuged and plasma (P) and blood cells (BC) were isolated. Samples of P and BC were also precipitated, centrifuged and insoluble (IF) and soluble (SF) separated. The percentage of radioactivity (% ATI) in BC, IF-P and IF-BC was calculated. Histological evaluations were performed and the morphology of the red blood cells was observed under optical microscopy showing important morphological alterations on the shape of the RBC treated with 6.25% M. Crispa L. extract. The % ATI decreased: on BC from 97.3 ± 1.92 to 60.0 ± 2.44; on IF-P from 74.8 ± 3.78 to 9.99 ± 3.61; on IF-BC from 88.6 ± 5.41 to 58.4 ± 11.55. The substances of the M. Crispa L. extract could increase the valence of these stannous (+2) ions to stannic (+4) and this fact would decrease the % ATI on blood elements and indicates the possible presence of oxidant agents in the M. Crispa L. extract. (author)

  18. Characterization of technetium-99m-L,L-ECD for brain perfusion imaging, Part 1: Pharmacology of technetium-99m ECD in nonhuman primates

    Walovitch, R.C.; Hill, T.C.; Garrity, S.T.; Cheesman, E.H.; Burgess, B.A.; O' Leary, D.H.; Watson, A.D.; Ganey, M.V.; Morgan, R.A.; Williams, S.J. (E.I. Du Pont de Nemours Co., Inc., No. Billerica, MA (USA))

    1989-11-01

    Technetium-99m ethyl cysteinate dimer (({sup 99m}Tc)ECD) is a neutral, lipophilic complex which rapidly crosses the blood-brain barrier. Brain retention and tissue metabolism of ({sup 99m}Tc)ECD is dependent upon the stereochemical configuration of the complex. While both L,L and D,D enantiomers are extracted by the brain, only the L,L but not the D,D form, is metabolized and retained in the monkey brain (4.7% injected dose initially, T 1/2 greater than 24 hr). Dynamic single photon emission computed tomography imaging studies in one monkey indicates {sup 99m}Tc-L,L-ECD to be distributed in a pattern consistent with regional cerebral blood flow for up to 16 hr postinjection. Dual-labeled {sup 99m}Tc-L,L-ECD and ({sup 14}C)iodoantipyrine autoradiography studies performed 1 hr after administration show cortical gray to white matter ratios of both isotopes to be equivalent (approximately 4-5:1). These data suggest that {sup 99m}Tc-L,L-ECD will be useful for the scintigraphic assessment of cerebral perfusion in humans.

  19. Technetium-99m DMSA preparation: Trivial issues causing severe problems

    Urinary tract infection (UTI) in children involving renal parenchyma, upper collecting system or bladder is one of the major causes for consideration in the diagnosis and management of paediatric nuclear medicine. Acute pyelonephritis is one of the prime causes of morbidity associated with urinary tract infection in children which can lead to progressive renal damage. Technetium-99m dimercaptosuccinic acid (DMSA) is used extensively for the assessment of UTI in paediatrics. The radiopharmaceutical preparation could be influenced by several factors, most of them are trivial, but invariably have severe impact on the quality of the scintiphotographs. This communication is mainly to highlight some of the issues related to 99mTc-DMSA preparation and the possible precautionary measures that need to be taken to obviate unwarranted problems. (author)

  20. Technetium-99m sestamibi: an indicator of breast cancer invasiveness

    As recently shown, angiogenesis is the most reliable marker of breast cancer invasiveness. Unfortunately it must be assessed by immunohistochemistry on tissue specimens. We have used technetium-99m sestamibi, a marker of regional blood flow in other organs that often but not always images breast cancer, to assess the invasiveness of this tumour. Nineteen patients, ten with nodal metastases and nine without any metastases, were studied with 99mTc-sestamibi scintigraphy before operation. Angiogenesis was quantitatively assessed by immunohistochemical staining of endothelia for factor VIII. All the node-positive (N+) patients at surgical revesion showed a positive 99mTc-sestamibi scan of the primary tumour and all the N-patients were negative. Nine out of ten N+ and sestamibi-positive tumours showed more than 135 microvessels/mm2 and one showed 99 microvessels/mm2; by contrast there were 71.6±12.1 microvessels/mm2 in the nine N- and sestamibi-negative tumours. Our study suggests that 99mTc-sestamibi is a marker of breast cancer invasiveness: its uptake is related to angiogenesis and, possibly, to oxidative metabolism of the tumour. (orig.)

  1. Technetium-99m sestamibi: an indicator of breast cancer invasiveness

    Scopinaro, F. (Section of Nuclear Medicine, Dept. of Experimental Medicine, Univ. ' La Sapienza' , Rome (Italy)); Schillaci, O. (Section of Nuclear Medicine, Dept. of Experimental Medicine, Univ. ' La Sapienza' , Rome (Italy)); Scarpini, M. (1st Inst. of Surgery, Univ. ' La Sapienza' , Rome (Italy)); Mingazzini, P.L. (1st Inst. of Surgery, Univ. ' La Sapienza' , Rome (Italy)); Di Macio, L. (Section of Nuclear Medicine, Dept. of Experimental Medicine, Univ. ' La Sapienza' , Rome (Italy)); Banci, M. (Section of Nuclear Medicine, Dept. of Experimental Medicine, Univ. ' La Sapienza' , Rome (Italy)); Danieli, R. (Section of Nuclear Medicine, Dept. of Experimental Medicine, Univ. ' La Sapienza' , Rome (Italy)); Zerilli, M. (1st Inst. of Surgery, Univ. ' La Sapienza' , Rome (Italy)); Limiti, M.R. (1st Inst. of Surgery, Univ. ' La Sapienza' , Rome (Italy)); Centi Colella, A. (Section of Nuclear Medicine, Dept. of Experimental Medicine, Univ. ' La Sapienza' , Rome (Italy))

    1994-09-01

    As recently shown, angiogenesis is the most reliable marker of breast cancer invasiveness. Unfortunately it must be assessed by immunohistochemistry on tissue specimens. We have used technetium-99m sestamibi, a marker of regional blood flow in other organs that often but not always images breast cancer, to assess the invasiveness of this tumour. Nineteen patients, ten with nodal metastases and nine without any metastases, were studied with [sup 99m]Tc-sestamibi scintigraphy before operation. Angiogenesis was quantitatively assessed by immunohistochemical staining of endothelia for factor VIII. All the node-positive (N+) patients at surgical revesion showed a positive [sup 99m]Tc-sestamibi scan of the primary tumour and all the N-patients were negative. Nine out of ten N+ and sestamibi-positive tumours showed more than 135 microvessels/mm[sup 2] and one showed 99 microvessels/mm[sup 2]; by contrast there were 71.6[+-]12.1 microvessels/mm[sup 2] in the nine N- and sestamibi-negative tumours. Our study suggests that [sup 99m]Tc-sestamibi is a marker of breast cancer invasiveness: its uptake is related to angiogenesis and, possibly, to oxidative metabolism of the tumour. (orig.)

  2. Technetium-99m Radiopharmaceuticals in Neurology. Chapter 6

    The ideal radioisotope for single photon emission computed tomography imaging is 99mTc, due to its physical decay characteristics, its availability through commercially available generator systems and its low cost per dose. Technetium-99m hydrophilic complexes are used to evaluate the integrity of the blood-brain barrier, while neutral and lipophilic complexes are used as brain perfusion imaging agents for determination of changes in regional cerebral blood flow in various neurological disorders. Radiopharmaceuticals that bind to central nervous system (CNS) receptors in vivo are useful for understanding the pathophysiology of a number of neurological and psychiatric disorders, their diagnosis and treatment. Nowadays, CNS receptor imaging agents are, with some exceptions, typically positron emission tomography radionuclide based radiopharmaceuticals. The reason for this is not based on principal but is rather as a result of the fact that efforts in the direction of 99mTc containing agents have not been strong or consistent enough. In the chapter, the progress made in the development of 99mTc complexes for imaging dopamine transporter, 5-HT1A receptor and amyloid plaques is presented. (author)

  3. Detection of obstructive uropathy using 99m technetium diethylenetriaminepentaacetic acid

    A simple, accurate test with no morbidity and effective for the detection of urinary tract obstruction in patients with normal and impaired renal function would be of significant clinical use. The ability of 99m technetium diethylenetriaminepentaacetic acid to detect the presence or absence of obstruction is evaluated. Obstructions were defined as abnormal retention of activity in the collecting system persisting in the delayed images. Diethylentriaminepentaacetic acid identified correctly 13 of 13 patients proved to have obstruction and 17 of 18 without obstruction. These data indicate a sensitivity of 100 percent, specificity of 94 percent and accuracy of 97 percent

  4. Detection of obstructive uropathy using 99m technetium diethylenetriaminepentaacetic acid

    Powers, T.A.; Grove, R.B.; Bauriedel, J.K.; Orr, S.C.; Melton, R.E.; Bowenn, R.D.

    1980-11-01

    A simple, accurate test with no morbidity and effective for the detection of urinary tract obstruction in patients with normal and impaired renal function would be of significant clinical use. The ability of 99m technetium diethylenetriaminepentaacetic acid to detect the presence or absence of obstruction is evaluated. Obstructions were defined as abnormal retention of activity in the collecting system persisting in the delayed images. Diethylentriaminepentaacetic acid identified correctly 13 of 13 patients proved to have obstruction and 17 of 18 without obstruction. These data indicate a sensitivity of 100 percent, specificity of 94 percent and accuracy of 97 percent.

  5. Technetium 99m pertechnetate thyroid scintigraphy: Congenital hypothyroid screening

    Technetium 99m pertechnetate thyroid scans were performed on 57 infants referred for evaluation of suspected congenital hypothyroidism. Thyroid anatomy may be characterized by four general types, based on the scintigraphic findings: (1) normal size and location. (2) ectopic location. (3) no detectable thyroid activity. (4) normal location with increased size or uptake. There are diverse etiologies of congential hypothyroidism. Correlation of thyroid scintigraphy with blood T4 and TSH levels allows specific etiological diagnosis in the majority of cases of congential hypothyroidism. (orig.)

  6. Stabilized alcohol solution of reducing salt formulations for use in preparing radioisotope labelled scanning agents: liver scanning technetium-99m colloid and method of preparation

    The preparation of a radiolabelled scanning agent for imaging reticuloendothelial organs, including the liver and spleen, is described. It consists of a sup(99m)Tc labelled colloid of a metal ion salt reductant, such as SnCl2, TiCl3, CrCl2 or FeCl2, and an anhydrous non-oxidising organic solvent, such as diethyl ether, ethanol or another aliphatic alcohol. Examples are given of the effects of varying the pH, the metal ion salt reductant concentration, the eluate and solvent volumes and the temperature of the radiopharmaceutical on the tagging efficiency and organ distribution in mice and rabbits. (U.K.)

  7. Novel 99mTc labeled

    FAN; Caiyun

    2006-01-01

    ,Nucl.Med.Biol.,2003,30:273-284.[33]John,C.S.,Lim,B.B.,Geyer,B.C.Et al.,99mTc-labeled σ-receptor-binding complex:Synthesis,characterization,and specific binding to human ductal breast carcinoma (T47D) cells,Bioconj.Chem.,1997,8:304-309.[34]Choi,S-R.,Yang,B.,P(o)ssl,K.Et al.,Development of a Tc-99m labeled sigma-2 receptor-specific ligand as a potential breast tumor imaging agent,Nucl.Med.Biol.,2001,28:657-666.[35]Zhang,Y.,Williams,W.,Torrence-Campbell,C.et al.,Characterization of novel N,N′-disubstituted piperazines as sigma receptor ligands,J.Med.Chem.,1998,41:4950-4957.[36]Maeda,D.N.,Williams,W.,Kim,W.E.et al.,N-arylalkylpi-peridines as high-affinuty sigma-1 and sigma-2 receptor ligands:Phenylpropylamine as potential leads for selective sigma-2 agents,Bioorg.Med.Chem.Lett.,2002,12:497-500.[37]Moore,T.S.,Boyle,M.,Thorn,V.M.et al.,N-substituted derivatives of piperazine and ethylenediamine,Part Ⅰ.The preparation of N-monosubstituted derivatives,J.Chem.Soc.,1929:39.[38]Stewart,H.W.,Turner,R.J.,Denton,J.J.et al.,Experimental chemotherapy of filariasis,Ⅳ.The preparation of derivatives of piperazine,J.Org.Chem.,1948,13:134-143.[39]O'Neil,J.P.,Wilson,S.R.,Katzenellenbogen,J.A.,Preparation and structural characterization of monoamine-monoamide bis(thio) oxo complexes of technetium(V) and rhenium(V),Inorg.Chem.,1994,33:319-323.[40]Bowen,W.D.,Sigma receptors:Recent advances and new clinical potentials,Pharm.Acta Helv.,2000,74:211-218.[41]Deuther-Conrad,W.,Patt,J.T.,Feuerbach,D.et al.,Norchloro-fluoro-homoepibatidine:Specificity to neuronal nicotinic acetylcholine receptor subtypes in vitro,IL Farmaco,2004,59:785-792.[42]Vilner,B.J.,Bowen,W.D.,Modulation of cellular calcium by sigma-2 receptors:Release form intracellular stores in human SK-N-SH neuroblastoma cells,J.Pharmacol.Exp.Ther.,2000,292:900-911.[43]Cheng,Y.,Prusoff,W.H.,Relationship between the inhibition constant (Ki) and the concentration of inhibitor which cause 50% inhibition (IC50) of an enzymatic reaction

  8. Lanreotide and octreotide complexed with technetium-99m: labeling, stability and biodistribution studies Lanreotídeo e octreotídeo complexados com tecnécio-99m: estudo de marcação estabilidade e estudos de biodistribuição

    Bluma Linkowski Faintuch

    2004-03-01

    Full Text Available Lanreotide and Octreotide are cyclic octapeptide analogues of somatostatin that were labeled with the radioisotope Technetium-99m for use in diagnostic nuclear medicine. The peptides were processed in a tartrate/phthalate buffer solution containing reducing agent. The purpose of this investigation was to optimize direct labeling by varying some parameters, and to evaluate radiochemical stability and biodistribution in animals. The marked peptides were obtained with high labeling efficiency and no need for subsequent purification. Best radiolabeling results corresponded to a molar ratio of SnCl2.H2O/peptide of 4.5. 99mTc-peptides were radiochemically stable for 6 hours. 99mTc-octreotide was relatively more susceptible to cysteine challenge than 99mTc-lanreotide. 99mTc-peptides were mainly distributed in the gastrointestinal tract but 99mTc-lanreotide showed a greater uptake by the liver than 99mTc-octreotide. Results indicated that the products can be obtained with high radiochemical yield, in a simple routine appropriate for further studies to assess their efficacy in radiodiagnosis.Lanreotídeo e octreotídeo são octapeptídeos cíclicos análogos da somatostatina e têm sido marcados com Tecnécio-99m para uso em diagnóstico na Medicina Nuclear. Os peptídeos são preparados em solução tampão ftalato/tartarato contendo um agente redutor. O objetivo deste estudo foi a otimização da marcação direta variando alguns parâmetros e a avaliação da estabilidade radioquímica e biodistribuição em animais. Os peptídeos marcados foram obtidos com alta eficiência de marcação e sem a necessidade de etapa de purificação no final do processo. Os melhores resultados de radiomarcação corresponderam á razão molar de SnCl2.2H2O/peptídeo de 4,5. Os peptídeos-99mTc mostraram-se radioquimicamente estáveis por 6 horas. Octreotídeo-99mTc mostrou-se relativamente mais suscetível frente à cisteína do que o lanreotídeo-99mTc. Os pept

  9. Production technologies for molybdenum-99 and technetium-99m

    Technetium-99m (6.02 h) is the most widely used radioisotope in nuclear medicine, accounting for more than 80% of all diagnostic nuclear medicine procedures. It is almost exclusively produced from the decay of its parent 99Mo. The present sources of 99Mo are research reactors by using the (n,γ) nuclear reaction with natural Mo (98Mo, ∼24%), resulting in inexpensive but low-specific activity 99Mo, or by neutron-induced fission of 235U, which results in expensive but high specific activity 99Mo. This publication covers several aspects related to the production of 99Mo and 99mTc. The contributed papers reflect the current status of the technology and discuss potential alternative methodologies for the production of 99Mo and 99mTc for medical use. The first four papers address the technologies using nuclear reactors, including the description of a new method using an aqueous homogenous reactor core for production of fission 99Mo and the latest development efforts to fabricate 235U low enriched targets (LEU, 235U). The next five papers discuss the potential of utilizing particle accelerators and assess the current status of the available nuclear data for the production of both, 99Mo and 99mTc with proton and deuteron beams. The last paper discusses a new technology based on gel system for the preparation of 99Mo/99mTc generators using low specific activity 99Mo produced in research reactors by the neutron activation of natural and inexpensive molybdenum oxide targets. Each individual paper was indexed and abstracted

  10. Technetium-99m NGA functional hepatic imaging: preliminary clinical experience

    Technetium-99m galactosyl-neoglycoalbumin ( [Tc]NGA) is a radiolabeled ligand to hepatic binding protein, a receptor which resides at the plasma membrane of hepatocytes. This receptor-binding radiopharmaceutical and its kinetic model provide a noninvasive method for the assessment of liver function. Eighteen patients were studied: seven with hepatoma, eight with liver metastases, four with cirrhosis, and one patient with acute fulminant non-A, non-B hepatitis. Technetium-99m NGA liver imaging provided anatomic information of diagnostic quality comparable to that obtained with other routine imaging modalities, including computed tomography, angiography, ultrasound, and [Tc]sulfur colloid scintigraphy. Kinetic modeling of dynamic [Tc]NGA data produced estimates of standardized hepatic blood flow, Q (hepatic blood flow divided by total blood volume), and hepatic binding protein concentration, [HBP]. Significant rank correlation was obtained between [HBP] estimates and CTC scores. This correlation supports the hypothesis that [HBP] is a measure of functional hepatocyte mass. The combination of decreased Q and markedly reduced [HBP] may have prognostic significance; all three patients with this combination died of hepatic failure within 6 wk of imaging

  11. Study of technetium behaviour in radiopharmaceuticals. Characterization of sup(99m)Tc-pyrophosphate, sup(99m)Tc-dimercaptosuccinate, sup(99m)Tc-diethylenetriaminepentaacetate complexes and sup(99m)Tc-colloidal rhenium sulphide

    The chemistry of technetium in extremely dilute solution was approached through the study of three complexing agents and a colloid. By the application of high-performance chromatographic techniques to the analysis of (Tc-pyro), (Tc-DTPA), (Tc-DMSA) complexes it was possible to isolate one or more chelates from a single complexing agent. Addition of pertechnetates to a solution of sodium pyrophosphates and stannous chloride at neutral pH leads to the formation of two complexes, both highly osteotropic. By the use of sup(117m)Sn it was shown that tin employed as reducing agent enters into the composition of one of the two complexes, either of which may be obtained preferentially by varying the (Sn)/(pyro) ratio. With technetium at acid pH (2.5) DMSA gives one or more chelates according to the concentration of the reagents present. DTPA with technetium at neutral pH gives a single complex for which a structure is proposed. The addition of calcium, indispensable for DTPA injection, leads to the appearance of a second bimetallic complex in very much smaller proportions than the first. The size distribution of some colloids was studied by ultrafiltration and permeation on gel. The preparation of colloidal rhenium sulphide and the technetium labelling conditions needed to obtain a very fine colloid were developed. The behaviour of technetium in the presence of colloidal rhenium sulphide and tin pyrophosphate was followed by sup(99m)Tc - sup(186)Re and sup(99m)Tc - sup(117m)Sn double-labelling tests. One reduced technetium fraction associates with the hydrolysed tin, the other follows the rhenium sulphide

  12. Technetium-99m-dimethylglyoxime ([sup 99m]Tc-DMG) as renal imaging agent

    Adonaylo, V.N. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales Buenos Aires Univ. (Argentina). Dept. de Ciencias Biologicas); Stahl, Adriana; Pomilio, A.B.; Vitale, A.A. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales); Canellas, C.O. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

    1993-06-01

    Dimethylglyoxime (DMG) labelled with [sup 99m]Tc is presented as a renal imaging agent. The behaviour of this complex was analysed at different pH by means of UV spectral data and using DMG-calcium chloride as a reference complex. Biokinetic data were evaluated in two biological models, Sprague-Dawley rats and Didelphis albiventris argentine opossum. Biodistribution in rats demonstrated fast and specific renal excretion. Time-activity values over both kidneys could be quantified for this complex. Renographic studies led to mean time-to maximum values on twelve assays of 2.0 [+-] 0.1 min and a mean relative function of 53.0 [+-] 2.3 and 47.0 [+-] 3.2 for right and left kidneys, respectively. [sup 99m]Tc-DMG showed specificity for the renal excretion pathway and therefore seems to be a very useful radiopharmaceutical for renal function studies. (Author).

  13. Technetium-99m-dimethylglyoxime (99mTc-DMG) as renal imaging agent

    Dimethylglyoxime (DMG) labelled with 99mTc is presented as a renal imaging agent. The behaviour of this complex was analysed at different pH by means of UV spectral data and using DMG-calcium chloride as a reference complex. Biokinetic data were evaluated in two biological models, Sprague-Dawley rats and Didelphis albiventris argentine opossum. Biodistribution in rats demonstrated fast and specific renal excretion. Time-activity values over both kidneys could be quantified for this complex. Renographic studies led to mean time-to maximum values on twelve assays of 2.0 ± 0.1 min and a mean relative function of 53.0 ± 2.3 and 47.0 ± 3.2 for right and left kidneys, respectively. 99mTc-DMG showed specificity for the renal excretion pathway and therefore seems to be a very useful radiopharmaceutical for renal function studies. (Author)

  14. Technetium 99m mercaptoacetyltriglycine gamma camera clearance calculations: Methodological problems

    Major sources of errors in the gamma-camera methods for the calculation of renal clearance are the accuracy of background correction for obtaining the true renal time-activity curve and the validity of the externally recorded pre-cordial activity as an estimate of the plasmatic time-activity curve. With technetium 99m mercaptoacetyltriglycine (99mTc-MAG3), because of its high protein plasma binding, one could expect minimal extravascular diffusion and hence a more accurate externally detected plasmatic curve. The high extraction rate should reduce the influence of the background, but, on the other hand, the effect of hepatobiliary excretion on the calculation of renal clearance might be significant. Our results suggest that the hepatobiliary excretion of 99mTc-MAG3 does not influence the gamma-camera renal clearance determination, even in patients with low renal function. However, the pre-cordial curve does not reflect accurately the plasmatic disappearance curve; its calibration with a single plasma sample taken at the 20th min is responsible for significant errors, probably because of an unfavourable ratio between the intravascular and extravascular activities at the 20th min. (orig.)

  15. Periarticular uptake of /sup 99m/technetium diphosphonate in psoriatics. Correlation with cutaneous activity

    Namey, T.C. (Medical Univ. of South Carolina, Charleston); Rosenthall, L.

    1976-01-01

    The periarticular uptake of /sup 99m/technetium-labeled diphosphonate (/sup 99m/TcDP) was compared in 12 patients hospitalized for psoriasis and in 12 hospitalized for other dermatoses not associated with arthropathy. The 12 patients with psoriasis had recent onset disease of less than 5 years duration; neither group had historical or clinical evidence of arthritis. All psoriatics had markedly abnormal scans with symmetrically increased periarticular uptake about the imaged joints. None of the controls had similar findings. In 4 patients scanned with /sup 99m/technetium-pertechnetate within 24 hours of their /sup 99m/TcDP scan, no evidence of inflammatory synovitis was found. Three of these patients were serially imaged with /sup 99m/TcDP at intervals of 2 weeks to 3 months after their initial study, when obvious clinical improvement in their psoriasis was apparent. Improvement in the radionuclide joint images was demonstrated in some of the patients, but none reverted to normal during the study period. In light of recent evidence for the preferential binding of /sup 99m/TcDP to immature collagen, it is suggested that psoriasis may represent a generalized, but uncharacterized, collagen disorder present in bone as well as skin, linking the cutaneous disease with the potential for arthropathy.

  16. Periarticular uptake of /sup 99m/technetium diphosphonate in psoriatics. Correlation with cutaneous activity

    The periarticular uptake of /sup 99m/technetium-labeled diphosphonate (/sup 99m/TcDP) was compared in 12 patients hospitalized for psoriasis and in 12 hospitalized for other dermatoses not associated with arthropathy. The 12 patients with psoriasis had recent onset disease of less than 5 years duration; neither group had historical or clinical evidence of arthritis. All psoriatics had markedly abnormal scans with symmetrically increased periarticular uptake about the imaged joints. None of the controls had similar findings. In 4 patients scanned with /sup 99m/technetium-pertechnetate within 24 hours of their /sup 99m/TcDP scan, no evidence of inflammatory synovitis was found. Three of these patients were serially imaged with /sup 99m/TcDP at intervals of 2 weeks to 3 months after their initial study, when obvious clinical improvement in their psoriasis was apparent. Improvement in the radionuclide joint images was demonstrated in some of the patients, but none reverted to normal during the study period. In light of recent evidence for the preferential binding of /sup 99m/TcDP to immature collagen, it is suggested that psoriasis may represent a generalized, but uncharacterized, collagen disorder present in bone as well as skin, linking the cutaneous disease with the potential for arthropathy

  17. labelling and quality control of some 99m Tc-radiopharmaceuticals of expected biological activity

    this thesis addresses the labelling and quality control of some 99mTc-radiopharmaceuticals which could be used for infection imaging. this study focuses on the labelling of sarafloxation, gatifloxation and cefepine with technetium-99m and biological evaluation of these labeled complexes and biodistribution in both normal and inflamed mice. the thesis is organized into two chapters: chapter I :labelling of some antibiotics chapter II :biological evaluation.

  18. Effect of a peel passion fruit flour (Passiflora edulis f. flavicarpa extract on the labeling of blood constituents with technetium-99m and on the morphology of red blood cells

    Bernardo Machado Rebello

    2007-09-01

    Full Text Available Passiflora edulis f. flavicarpa (maracuja is a fruit consumed in Brazil and worldwide. Blood constituents labeled with technetium-99m (99mTc are used in nuclear medicine. The effect of P. flavicarpa extract on the radiolabeling of blood constituents and on red blood cells morphology was evaluated. Blood samples from Wistar rats was incubated with P. flavicarpa extract. After that, the labeling of blood constituents with 99mTc was carried out. Samples of plasma and blood cells were precipitated with trichloroacetic acid to isolate the soluble and insoluble fractions of plasma and blood cells. The radioactivity in each fractions was counted and the percentage of radioactivity was determined. Blood smears were also prepared to morphological evaluation and perimeter/area ratio determination. P. flavicarpa extract altered (pPassiflora edulis f. flavicarpa (maracujá é um fruto consumido no Brasil e no mundo. O efeito de um extrato de farinha da casca de maracujá na marcação dos constituintes sangüíneos com tecnécio-99m e na morfologia de hemácias foi avaliado. Amostras de sangue de ratos Wistar, foram incubadas com extrato de P. flavicarpa. Em seguida, o procedimento de marcação de constituintes sangüíneos com Tc-99m foi realizado. Amostras de plasma e células sangüíneas foram separadas e alíquotas destas frações foram precipitadas com ácido tricloroacético para isolamento das frações solúvel e insolúvel do plasma e das células sangüíneas. A radiatividade em cada fração foi contada a porcentagem de radioatividade (%ATI foi calculada. Distensões sangüíneas foram também preparadas para avaliação morfológica e da relação perímetro/área de hemácias. O extrato de P. flavicarpa alterou a fixação do 99mTc nas proteínas plasmáticas e a relação perímetro/área das hemácias. Substâncias presentes no extrato de P. flavicarpa poderiam afetar a marcação de constituintes sangüíneos com 99mTc atuando em alvos

  19. Guarana (Paullinia cupana) effect on radiolabelling of erythrocytes with Technetium-99m; Efeito do guarana (Paulinnia cupana) na marcacao de hemaceas com tecnecio-99m

    Oliveira, Joelma F.; Braga, Ana Cristina S.; Avila, Antonio Sergio R.; Gutfilen, Bianca [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia; Bernardo-Filho, Mario [Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil)

    1996-07-01

    The labelling of red blood cells (RBC) with technetium-99m (Tc-99m) have been used for many studies in nuclear medicine. This labeling procedure depends on a reducing agent and stannous chloride is normally used for this purpose. Many factors, including drug therapy, can affect the biodistribution of radiopharmaceuticals, such factors many lead to poor organ visualization, requirement to repeat the examination procedure or even misdiagnosis. Guarana (Paullinia cupana) is commonly used in popular medicine. Here, we investigate if guarana is capable to alter the labeling of RBC with Tc-99m and to modify the radioactivity binding to plasma proteins and cellular constituents from insoluble and soluble fractions. The results were obtained with blood samples from Wistar rats with heparine and incubated with different guarana solutions. The percentage of radioactivity (% rad) from BC and P were calculated. The distribution of radioactivity in P and BC showed that the uptake of Tc-99m decreased significantly in all concentrations. (author)

  20. Technetium-99m-labelled red blood cell imaging in the diagnosis of hepatic haemangiomas: the role of SPECT/CT with a hybrid camera

    Delayed liver single-photon emission computed tomography (SPECT) after 99mTc red blood cell (RBC) labelling is helpful in detecting hepatic haemangiomas; however, diagnosis can be difficult when lesions are situated adjacent to structures like the inferior vena cava, the heart or hepatic vessels, where blood activity persists. The aims of this study were to evaluate the usefulness of RBC SPECT and transmission computed tomography (RBC SPECT/CT) performed simultaneously with a hybrid imaging system for correct characterisation of hepatic lesions in patients with suspected haemangioma, and to assess the additional value of fused images compared with SPECT alone. Twelve patients with 24 liver lesions were studied. The acquisitions of both anatomical (CT) and functional (SPECT) data were performed during a single session. SPECT images were first interpreted alone and then re-evaluated after adding the transmission anatomical maps. Image fusion was successful in all patients, with perfect correspondence between SPECT and CT data, allowing the precise anatomical localisation of sites of increased blood pool activity. SPECT/CT had a significant impact on results in four patients (33.3%) with four lesions defined as indeterminate on SPECT images, accurately characterising the hot spot foci located near vascular structures. In conclusion, RBC SPECT/CT imaging using this hybrid SPECT/CT system is feasible and useful in the identification or exclusion of suspected hepatic haemangiomas located near regions with high vascular activity. (orig.)

  1. Technetium-99m-labelled red blood cell imaging in the diagnosis of hepatic haemangiomas: the role of SPECT/CT with a hybrid camera

    Schillaci, Orazio; Danieli, Roberta; Manni, Carlo; Capoccetti, Francesca; Simonetti, Giovanni [Department of Biopathology and Diagnostic Imaging, University ' ' Tor Vergata' ' , Rome (Italy)

    2004-07-01

    Delayed liver single-photon emission computed tomography (SPECT) after {sup 99m}Tc red blood cell (RBC) labelling is helpful in detecting hepatic haemangiomas; however, diagnosis can be difficult when lesions are situated adjacent to structures like the inferior vena cava, the heart or hepatic vessels, where blood activity persists. The aims of this study were to evaluate the usefulness of RBC SPECT and transmission computed tomography (RBC SPECT/CT) performed simultaneously with a hybrid imaging system for correct characterisation of hepatic lesions in patients with suspected haemangioma, and to assess the additional value of fused images compared with SPECT alone. Twelve patients with 24 liver lesions were studied. The acquisitions of both anatomical (CT) and functional (SPECT) data were performed during a single session. SPECT images were first interpreted alone and then re-evaluated after adding the transmission anatomical maps. Image fusion was successful in all patients, with perfect correspondence between SPECT and CT data, allowing the precise anatomical localisation of sites of increased blood pool activity. SPECT/CT had a significant impact on results in four patients (33.3%) with four lesions defined as indeterminate on SPECT images, accurately characterising the hot spot foci located near vascular structures. In conclusion, RBC SPECT/CT imaging using this hybrid SPECT/CT system is feasible and useful in the identification or exclusion of suspected hepatic haemangiomas located near regions with high vascular activity. (orig.)

  2. Production of technetium-99m for nuclear-medical application

    Technetium-99m is the most important radioisotope for nuclear-medical application. The main source of sup 9 sup 9 sup m Tc are now sup 9 sup 9 Mo/ sup 9 sup 9 Tc generators based on fission-produced sup 9 sup 9 Mo. In principle the separation of sup 9 sup 9 Tc from its parent sup 9 sup 9 Mo can be achieved by using several methods. However the most important is chromatography. In the paper the possibilities of the production of sup 9 sup 9 Mo in nuclear reactor and cyclotron are given. The results of the production of sup 9 sup 9 Tc in Yugoslavia are reviewed (author)

  3. Technetium 99m methylene diphosphonate bone scanning in osteoarthritic hands

    In this prospective study, the radiological features characteristic of osteoarthritis of the hand were compared with the radionuclide bone scan images. A total of 32 patients was assessed at 6-monthly intervals for 18 months. Microfocal radiographs were taken at each visit. The high magnification and resolution of this technique permitted direct measurement of joint space width, subchondral sclerosis, osteophyte number and area and juxta-articular radiolucency area for each joint in the hand. Four-hour technetium 99m methylene diphosphonate bone scans were taken at 0 and 12 months and the activity of tracer uptake at each joint scored. The latter was compared with each X-radiographic feature at every visit and the changes between visits analysed. The scan scores did not correlate with any of the X-radiographic features other than osteophyte size. During the study the size of growing and remodelling osteophytes increased significantly at joints with raised or increased isotope uptake. (orig.)

  4. Validation of 99mTechnetium-labeled mebrofenin hepatic extraction method to quantify meal-induced splanchnic blood flow responses using a porcine model

    Zacho, Helle Damgaard; Kristensen, Niels Bastian; Henriksen, Jens Henrik Sahl;

    2012-01-01

    flow; the intestinal and hepatic oxygen uptake; the net fluxes of oxygen, lactate, and glucose; and the extraction fraction (EF) of 99mTc-MBF were measured before and for 70 min after feeding. The mean baseline SBF was 2,961 ml/min vs. 2,762 ml/min measured by pAH and 99mTc-MBF, respectively, and...

  5. Quantification of ocular inflammation with technetium-99m glucoheptonate

    Histological and morphometric evaluation of ocular inflammation is difficult, particularly when there is extensive ocular involvement with abscess formation and necrosis. A quantitative imaging procedure applicable to humans would be important clinically. To establish such a procedure, turpentine-induced ocular inflammation was obtained by subconjunctival injection in the right eye of 55 rabbits. The left eye was used as control and injected with a volume of saline equal to the volume of turpentine in the right eye. Volumes of turpentine or saline were 0.02, 0.04, 0.06, 0.2 and 0.6 ml, and the rabbits were divided into groups 1-5, according to these volumes. Imaging was performed 48 h after turpentine injection and 6 h after intravenous injection of 10 mCi of technetium 99m glucoheptonate (99mTc-GH). An inflammatory reaction index (IRI), defined as the ratio of counts of the right eye divided by counts of the left eye, was used. IRIs were proportional to the degree of inflammation and allowed the distinction of 3 subgroups: One represented by group 4, one by group 5 and one by groups 1, 2 and 3. This method of quantification of ocular inflammatory processes using 99mTc-GH is original, rapid, non-invasive, reproducible and safe, although unable to differentiate inflammatory processes caused by doses of turpentine which are very small and close to each other. It is conceivable that its application to humans will bring new insight into the ocular inflammatory process and response to therapy. (orig.)

  6. Estudos in vitro e in vivo de análogo da timidina marcada com complexo organometálico de tecnécio-99m para potencial uso em diagnóstico tumoral Studies in vitro and in vivo of thymidine analog labeled with organometalic complex of technetium-99m for potential use in tumor diagnosis

    Rodrigo Luis Silva Ribeiro Santos

    2008-03-01

    Full Text Available Análogos da timidina têm sido marcados com diferentes radioisótopos devido ao seu potencial em monitorar a proliferação incontrolável de células. Considerando que o radioisótopo tecnécio-99m ainda mantém uma posição privilegiada devido às suas propriedades químicas e nucleares, este trabalho constituiu-se no desenvolvimento da marcação da timidina com o 99mTc, mediante o emprego de compostos organometálicos. Os objetivos principais foram a síntese do precursor carbonil-tecnécio-99m, marcação da timidina com este precursor, estudo da estabilidade, e avaliações radioquímicas e biológicas com animais sadios e portadores de tumor. A síntese do precursor organometálico e a marcação da timidina com este precursor foi realizada com > 97% e > 94% de pureza radioquímica, respectivamente, obtendo-se também uma boa estabilidade em até 6 h em temperatura ambiente. A transquelação frente aos aminoácidos cisteína e histidina apresentou perdas entre 8 e 11% para concentrações de até 300 mM. Os ensaios de biodistribuição em camundongos sadios indicaram que o complexo radiomarcado apresentou um rápido depuramento sangüíneo e baixa captação nos demais órgãos, com predominância de excreção da droga pelo sistema urinário e hepatobiliar. A captação tumoral foi de 0,28 e 0,18 %DI/g para tumor de pulmão e mama, respectivamente. Os resultados obtidos sugerem maiores investigações em outros análogos da timidina.Thymidine analogs have been labeled with different radioisotopes due to their potential in monitoring the uncontrollable cell proliferation. Considering that the radioisotope technetium-99m still keeps a privileged position as a marker due to its chemical and nuclear properties, this work was designed to develop a new technique of labeling of thymidine analog with 99mTc, by means of the organometallic compounds. The aims of this research were: synthesis of the organometallic precursor technetium-99m

  7. Cellular accumulation and retention of the technetium-99m-labelled hypoxia markers BRU59-21 and butylene amine oxime

    BRU59-21 and 99mTc-butylene amine oxime (BnAO, HL91) are being evaluated for imaging hypoxia in tumors. Both tracers: 1) rapidly reached a plateau in aerobic Chinese hamster ovary cells in vitro but continuously accumulated in hypoxic cells; 2) ceased to accumulate when hypoxic cells were exposed to air; 3) showed ∼40% retention upon washing the cells; 4) showed selective hypoxic accumulation only at 37 deg. C; 5) accumulation could be modulated by addition of electron-affinic compounds; and 6) exhibited higher accumulation in cells which overexpress cytochrome P450 reductase. Both BRU59-21 and 99mTc-BnAO share properties making them suitable for hypoxia imaging

  8. Radiolabeled, nonspecific, polyclonal human immunoglobulin in the detection of focal inflammation by scintigraphy: Comparison with gallium-67 citrate and technetium-99m-labeled albumin

    Rubin, R.H.; Fischman, A.J.; Needleman, M.; Wilkinson, R.; Callahan, R.J.; Khaw, B.A.; Hansen, W.P.; Kramer, P.B.; Strauss, H.W.

    1989-03-01

    The accumulation of nonspecific polyclonal human immunoglobulin (IgG) radiolabeled with /sup 125/I or /sup 111/In was compared to that of (/sup 67/Ga)citrate and (/sup 99m/Tc)albumin in rats with deep thigh inflammation due to Escherichia coli infection. Serial scintigrams were acquired at 1, 3, 24, and in some cases, 48 hr after injection. As early as 3 hr postinjection, (/sup 111/In)IgG showed greater accumulation at the lesion than (/sup 99m/Tc)HSA (p less than 0.01). Both (/sup 125/I)IgG and (/sup 111/In)IgG showed greater accumulation than (/sup 67/Ga)citrate (p less than 0.01). At 24 hr, IgG image definition increased, while HSA image definition decreased, and the intensity of accumulation of both IgG preparations was greater than that of (/sup 67/Ga)citrate or (/sup 99m/Tc)HSA (p less than 0.01). At all imaging times, (/sup 67/Ga)citrate accumulation was surprisingly low. In inflammation produced by Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Candida albicans, or turpentine, (/sup 111/In)IgG accumulation was similar to the results obtained with Escherichia coli. These studies suggest that focal sites of inflammation can be detected with radiolabeled nonspecific human polyclonal IgG.

  9. Radiolabeled, nonspecific, polyclonal human immunoglobulin in the detection of focal inflammation by scintigraphy: Comparison with gallium-67 citrate and technetium-99m-labeled albumin

    The accumulation of nonspecific polyclonal human immunoglobulin (IgG) radiolabeled with 125I or 111In was compared to that of [67Ga]citrate and [99mTc]albumin in rats with deep thigh inflammation due to Escherichia coli infection. Serial scintigrams were acquired at 1, 3, 24, and in some cases, 48 hr after injection. As early as 3 hr postinjection, [111In]IgG showed greater accumulation at the lesion than [99mTc]HSA (p less than 0.01). Both [125I]IgG and [111In]IgG showed greater accumulation than [67Ga]citrate (p less than 0.01). At 24 hr, IgG image definition increased, while HSA image definition decreased, and the intensity of accumulation of both IgG preparations was greater than that of [67Ga]citrate or [99mTc]HSA (p less than 0.01). At all imaging times, [67Ga]citrate accumulation was surprisingly low. In inflammation produced by Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Candida albicans, or turpentine, [111In]IgG accumulation was similar to the results obtained with Escherichia coli. These studies suggest that focal sites of inflammation can be detected with radiolabeled nonspecific human polyclonal IgG

  10. Technetium-99m-cyclam AK 2123: a novel marker for tumor hypoxia

    Technetium-99m labeled cyclam N-2'-methoxyethyl-2-(3'-nitro-1'-triazole) acetamide (cyclam AK 2123) has been synthesized, radiolabeled and characterized as a hypoxic tumor imaging agent. Radiochemical purity was greater than 95%. Marker biodistribution was measured in normal Wistar strain rats at different time intervals after intra venous (i.v.) administration. In vivo distribution and scintigraphic imaging studies were performed after i.v. injection into mammary tumor-bearing rats using a gamma camera and associated computer. Intratumor partial oxygen pressure (pO2) and oxygen saturation measurements were performed to estimate the oxygenation status of the tumors. Tumor to muscle ratio (T/M) of 99mTc-cyclam AK 2123 was 8.5 which was compared with other tumor seeking radiopharmaceuticals, viz. 99mTc-(V) DMSA (3.07), 99mTc-citrate (5.29) and 201T1C1 (3.29). T/M ratios were also evaluated in comparison with radioiodinated iodoazomycin galactopyronoside (125I-IAZG). The ratio obtained was 18 for 99mTc-cyclam AK 2123 and 20 for 125I-IAZG, respectively. The increased concentration of radioactivity in these tumors suggests that this agent could be labelling hypoxic cells and have utility as an imaging agent

  11. Technetium-99m production issues in the United Kingdom.

    Green, Christopher H

    2012-04-01

    Nuclear Medicine developed when it was realised that a radioisotopic substitution of Iodine-131 for the stable Iodine-127 would follow the same metabolic pathway in the body enabling the thyroid to be imaged and the thyroid uptake measured. The Iodine could be complexed with pharmaceutical substrates to enable other organs to be imaged, but its use was limited and high gamma energy and beta emission restricted the activity of each radiopharmaceutical used, leading to long acquisition times and degraded images. As a pure gamma emitter of 140 keV and with a 6-h half-life, Technetium-99m is a better radionuclide and images a wider range of bodily organs. However, its short half-life also requires it to be eluted from its mother radionuclide, Mo-99, in a generator, delivered weekly from radiopharmaceutical companies who obtain the Mo-99 in liquid form from high-flux research reactors. All went well till around 2007, when the NRU Reactor in Canada was closed and all other reactors went down for various periods for unrelated problems, leading to widespread Mo-99 shortages. Although the reactors have since recovered, they are 48 to 57 years old, and it seems that few governments have made any future provision such as building replacement reactors. PMID:22557795

  12. Fractionated elution using the TEKCIS technetium-99m generator.

    Vigne, Jonathan; De Mil, Rémy; Peyronnet, Damien; Hecquard, Claudine; Agostini, Denis; Lemonnier, Françoise

    2016-06-01

    The TEKCIS technetium-99m (Tc) generator was designed to allow dry column shipment and automatized conception. A high Tc radioactive concentration is required in a subset of radiopharmacy procedures. Fractionated elution can be a useful tool to meet this requirement, especially when current elution is close to the generator expiration date. The aim of our study was to assess TEKCIS generator elution kinetics and to determine the optimal fractionated elution time to fit with procedures requiring the highest Tc radioactive concentration in clinical use. After duplicate elution at several predetermined elution times, the volume and activity of each eluate were measured. Two optimal time points were selected to perform fractionated elution and repeatability (n=34 and 33) assessed on TEKCIS generators calibrated at 6 or 8 GBq. The complete eluate volume (5 ml) was collected after 60 s of elution. A logarithmic equation was established between eluate volume (v, ml) from elapsed elution time (t, s): v=1.8335ln(t)-2.5965. Using the reciprocal equation, elution times required to obtain some commonly eluted volumes were calculated. Fractionated elutions during 15 and 20 s were selected and an average elution volume from 2.74 to 3.27 ml was collected, with an average elution yield of approximately 90 and 100%, respectively. Our work provides a simple and reliable methodology for the use of fractionated elution with the new TEKCIS generator. PMID:26945284

  13. Reception and research of medical and biologic properties labelled tecnetium-99M ciprofloxacin of the hydlochloride

    Full text: The researches are carried out on creation of a reagent for reception labeled technetium-99m antimicrobial preparations. An estimation of influence of components of a reactionary mix on radiochemical cleanliness received preparations spent a method thinlayer chromatography in various environments. Formation colloid the tin absorbing more of 70 percent of a radioactive label is noted

  14. Dissemination of bacteria labeled with technetium-99m after laparotomy and abdominal insufflation with different CO2 pressures on rats Disseminação de bactérias marcadas com tecnécio-99m após laparotomia e insuflação com diferentes pressões de CO2 em ratos

    Marcos Bettini Pitombo

    2008-02-01

    Full Text Available PURPOSE: To asses the dissemination of bacteria labeled with technetium-99m (99mTc from peritoneal cavity after different surgical procedures. METHODS: Bacteria of the Escherichia coli species labeled with 99mTc were used in a concentration of 10(8 units of colony-makers for ml (UFC/ml and 1ml was inoculated through intra-peritoneal via. Forty-eight rats were divided into four groups: control, laparotomy, pneumoperitoneum with 10mmHg and pneumoperitoneum with 20mmHg of CO2. Procedures were performed 20 min after injection of the inoculum and lasted 30 min. Animals were sacrificed after six hours (Group 1 and 24 hours (Group 2. Samples of blood, liver and spleen were collected for radioactivity counting. RESULTS: After six hours, indirect detection of the bacteria in different organs was uniform in all groups. After 24 hours, a larger detection of technetium was observed in the livers of animals of the group insufflated with 20mmHg of CO2, when compared with those of control group (pOBJETIVO: Avaliar a disseminação de bactérias marcadas com tecnécio-99m (99mTc a partir da cavidade peritoneal após diferentes procedimentos cirúrgicos. MÉTODOS: Foram utilizadas bactérias da espécie Escherichia coli marcadas com 99mTc em uma concentração de10(8 unidades formadoras de colônia por ml (UFC/ml sendo inoculado 1ml por via intra-peritoneal. Quarenta e oito ratos foram divididos em quatro grupos: controle, laparotomia, pneumoperitôneo com 10 mmHg e pneumoperitôneo com 20 mmHg de CO2. Os procedimentos foram realizados 20 minutos após a injeção do inóculo e duraram 30 minutos. Os animais foram sacrificados após seis horas (grupo 1 e 24 horas (grupo 2. Foram coletadas amostras de sangue, fígado e baço para contagem radioativa. RESULTADOS: Após seis horas, a detecção indireta das bactérias nos diferentes órgãos foi uniforme em todos os grupos. Após 24 horas, observou-se uma maior detecção de tecnécio nos fígados dos animais do

  15. Specifications and Quality of Technetium99m Produced diopharmaceuticals According to Good Manufacturing Practice Regulations

    A Technological revolution has occurred in the last two decades of this century in field of Cold Kits preparations processed by Lyophilization technique (A drying process while frozen) which are labeled afterwards with Technetium-99m radionuclide. Such materials are intended to be used as Radiopharmaceutical probes in nuclear medicine for the diagnosis of dynamic and static conditions of organs, and therefore; uncovering of diseases and syndromes targeting humans. Preferability and the advantages of such kits labeled with Technetium-99m radionuclide over other types of radiopharmaceuticals is attributed to the unique physical properties of the radionuclide including its short half life of 6.02 hours, low photon energy of 140 keV, lacking of alpha and beta particles which are usually exposing patients to have additional exposed doses. Moreover, simplicity in obtaining such radionuclide in form portable generators containing the mother radionuclide Molybdenum - 99 (i.e. solvent extraction generators or adsorption column chromatographic generators) for-on-the- spot-labeling, and the ability of formulating the cold kits as chemical complexes located at different organs of human body. Those lyophilized kits intended for radiopharmaceutical preparations labeled with Technetium - 99m radionuclide must stand for quality assurance standards and assessments for the sake of safety, efficiency, apyrogenecity, radiochemical purity, in- vivo stability and suitability for the endeavor planed for. Therefore, in order to control and optimize those considerations, implementations of the so-called GOOD MANUFACTURING PRACTICE composed of regulations and constitutional laws related to the process of preparation and final produced preparation must take place.(author)

  16. Effects of a tomato (Solanum lycopersicum extract on the labeling of blood constituents with technetium-99m Efeitos de um extrato de tomate (Solanum lycopersicum na marcação de constituintes sangüíneos com tecnécio-99m

    Severo de Paoli

    2008-06-01

    Full Text Available Tomato (Solanum lycopersicum is the second most produced and consumed vegetable in the world. It has been indicated in the prevention and treatment of cancer, asthma and atherosclerosis. Blood constituents labeled with radionuclides have been used in procedures in nuclear medicine. Data have shown that food and drugs can alter the labeling of blood constituents with technetium-99m (99mTc. This study evaluated the influence of a tomato extract on this radiolabeling procedure. Heparinized blood (Wistar rats was incubated in vitro with different concentrations of a tomato extract and 99mTc-labeling was performed. Plasma (P and blood cells (BC were separated following soluble (SF-P/SF-BC and insoluble (IF-P/IF-BC fractions isolation by precipitation and centrifugation. The radioactivities on blood constituents (P, BC, IF-P, SF-P, IF-BC and SF-BC were determined and the percentage of radioactivity (%ATI was calculated. The tomato extract used at the highest concentrations (2.00 and 4.00g/mL, reduced significantly (p O tomate (Solanum lycopersicum é o segundo vegetal mais produzido e consumido no mundo, tendo sido indicado para prevenção e tratamento de câncer, asma e arteriosclerose. Constituintes sangüíneos marcados com radionuclídeos têm sido usados em procedimentos na medicina nuclear. Dados têm mostrado que alimentos e drogas podem alterar a marcação de constituintes sangüíneos com tecnécio-99m (99mTc. Este estudo avaliou a influência de um extrato de tomate neste procedimento de radiomarcação. Sangue heparinizado (Wistar rats foi incubado in vitro com diferentes concentrações de um extrato de tomate e a marcação com 99mTc foi realizada. Plasma (P e células sangüíneas (CS foram separadas permitindo o isolamento das frações solúvel (SF-P/SF-CS e insolúvel (IF-P/IF-CS por precipitação e centrifugação. A radioatividade nos constituintes sangüíneos (P, CS, IF-P, SF-P, IF-CS e SF-CS foi determinada e a porcentagem de

  17. Lymphoscintigraphic evaluation of leg lymphedema using intradermal injection of technetium 99m-labeled human serum albumin; Assessment of the effect of standing

    Uchisako, Hiromichi; Suga, Kazuyoshi; Ito, Katsuyoshi; Kuramitsu, Tatsuya; Tanaka, Nobuyuki; Nakaki, Hiroji; Nakanishi, Takashi; Esato, Kensuke (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1993-11-01

    Twenty-four patients with lymphedema of the lower limbs and seven normal subjects were examined by lymphoscintigraphy following an intradermal injection of [sup 99m]Tc-HSA. The effect of changing to a standing position was determined. In normal subjects, a large spiking wave and a rapid stepwise increase in tracer activity frequently occurred on standing, although a decreased phase appeared less often on time-activity curves. These findings indicated that lymphatic flow was increased after the load produced by standing. The frequency of these changes was decreased in the patients with lymphedema, indicating that lymphatic disruption was responsible for their edema. Thus, lymphoscintigraphy using a load produced by standing can provide useful information in patients with lymphedema of the legs. (author).

  18. Noninvasive quantitation of myocardial infarction with technetium-99m pyrophosphate

    We sought to quantitate infarct size using radioactive imaging techniques. Infarcts were created in closed chest dogs. Using a scintillation camera interfaced to a computer, infarct images were made in the anterior, left lateral, LAO, and RAO projections, 48 hours after infarction and 75 to 90 min following the intravenous injection of 15 mCi of technetium-99m pyrophosphate (Tc-PYP). Images were computer enhanced and area was calibrated with a radioactive grid source of known dimensions. Image radioactivity was normalized for decay and dose corrected for body weight. Animals were sacrificed two hours following the injection of Tc-PYP. Postmortem images were also computer enhanced and calibrated. Gross infarct area and weight were estimated and transmural biopsies were evaluated for Tc-PYP activity and analyzed for creatine phosphokinase (CPK) content. Contiguous biopsies were pathologically analyzed and graded. There was a negative correlation between tissue Tc-PYP activity and CPK content (r = -0.89). Pathologic severity worsened with increased Tc-PYP activity and diminished CPK content. There was a good correlation between gross infarct area and image infarct area, both in vivo (r = 0.79), and at post-mortem examination (r = 0.95). Gross infarct weight also correlated well with image infarct activity in vivo (r = 0.83 in the RAO view) and at postmortem examination (r = 0.87). An additional correlation between gross infarct weight and in vivo image infarct area (r = 0.92 in the LAO view) appeared most promising for future clinical evaluation. These experimental relationships are analyzed and future patient application of these imaging techniques are considered

  19. Dynamic SPECT of the brain using a lipophilic technetium-99m complex, PnAO

    Holm, S; Andersen, A R; Vorstrup, S;

    1985-01-01

    The lipophilic 99mTc-labeled oxime propylene amine oxime (PnAO) should, according to recent reports behave like 133Xe in the human brain. This study compares SPECT images of the two tracers in six subjects: four stroke cases, one transitory ischemic attack case and one normal subject. Technetium-99...... cerebral blood flow followed by rapid washout. In the stroke cases, low flow areas were equally well visualized by both tracers. Two dissimilarities were seen in the initial pictures: PnAO visualized the cerebral veins and showed a lesser contrast of gray:white matter uptake. The results suggest that Pn...

  20. A critical study of technetium 99m and xenon 133 lung scintigraphy in patients with cystic fibrosis

    During investigations for cystic fibrosis, 41 children, most of whom were aged 0 to 7 years, were submitted to lung scintigraphy with technetium 99m first and xenon 133 subsequently. This procedure ensured accurate location of pulmonary lesions. The reliability of the radio-isotopic study was assessed through comparison to conventional clinical and radiological criteria, arterial blood gas determinations and pulmonary function tests. Perfusion scintigraphy with technetium 99m labelled macroaggregated albumin (n=90) was compared to functional parametrical xenon 133 study (n=25) (perfusion-ventilation). The degree of lung disease was evaluated during serial examinations in order to improve prognostic prediction. Technetium 99m scintigraphy proves a reliable and sensitive procedure which accurately reflects the patients' clinical status when it is performed in the absence of patent pulmonary superinfection. Xenon 133 scintigraphy, which is more difficult to perform and interpret, has the advantage of providing a topographic and quantitative evaluation of pulmonary blood flow and ventilatory efficiency

  1. Comparison of 99mTc-labeled methionine and 11C methionine radiotracer in the detection of breast carcinomas

    The cost effectiveness and non-availability of Cyclotron in underdeveloped and developing countries is a basic problem. Therefore studies were undertaken after labeling Methionine with generator produced Technetium-99m for its possible use in breast cancer imaging

  2. Comparative myocardial uptake of technetium-99 m sestamibi and technetium-99m tetrofosmin one hour after stress injection

    Technetium-99m sestamibi and 99mTc-tetrofosmin are at present the preferred tracers for simultaneous assessment of myocardial perfusion and function by gated single-photon emission tomography (SPET). The aim of this work was to compare sestamibi and tetrofosmin myocardial uptake 1 h after stress injection. Consecutive unselected patients were studied either with sestamibi or with tetrofosmin on a random basis, until at least 100 patients had been enrolled for each gender and tracer. Stress was obtained by dipyridamole or exercise or combined dipyridamole + exercise; in the latter cases, exercise was sustained for at least 1.5 min after tracer injection. Injected activity was similarly adjusted to body weight. For each patient, imaging began 60-75 min after injection. All SPET projections were summed; due to the acquisition technology (''roving zoom'', i.e. a mobile zoom), the heart always appeared at the centre of the frame in all projections and in the sum image. Thus minimal lung background contamination could be assumed in an elliptic region of interest placed over the heart on the sum image. Three indexes were analysed: total myocardial counts (Sum), mean myocardial pixel (Mean) and maximum myocardial pixel (Max). Four patient groups were analysed: males with sestamibi or tetrofosmin (MS: n = 189 and MT: n = 157), females with sestamibi or tetrofosmin (FS: n = 101 and FT: n = 104). MS and MT groups were comparable for physical variables, maximum heart rate and stress type, as were the FS and FT groups. Sum, Mean and Max were significantly higher with sestamibi (P = 0.0001 by ANOVA). Comparing MS vs MT and FS vs FT, mean values ± SD were as follows: for Sum (kcounts) 750±184 vs 652±166, and 707±202 vs 594±189; for Mean (counts) 4517±1171 vs 4107±898, and 4908±1119 vs 4144±1025; and for Max (counts) 6471±1654 vs 5794±1312, and 7318±1886 vs 6152±1684. The mean gain with sestamibi was +15%, +10% and +12% in males, and +19%, +18% and +19% in females

  3. Sequential technetium-99m HMDP-gallium-67 citrate imaging for the evaluation of infection in the painful prosthesis

    In order to evaluate the clinical utility of sequential technetium-99m HMDP-gallium-67 scanning in patients with painful orthopedic prosthesis, a retrospective review was made of 154 sequential scans performed in 130 patients. Criteria for a positive study included spatially incongruent gallium-technetium uptake or gallium uptake that was congruent but more intense than technetium. Images were interpreted as negative if gallium was congruent and less intense than technetium. Sixty-six patients underwent surgery (31 infected, 35 aseptic), and 64 were evaluated clinically (3 infected, 61 aseptic). The combined results of the surgical and nonsurgical patients yielded a sensitivity of 66%, a specificity of 81%, and an accuracy of 77%. In this series, the technetium-gallium scan combination has proven to be helpful but more recent techniques such as indium-111-labeled leukocytes may prove to be superior to sequential technetium-gallium imaging

  4. Technetium-99m sestamibi kinetics in reperfused canine myocardium

    The purpose of the current study was to clarify the myocardial kinetics of technetium-99m sestamibi when the latter is administered during reperfusion. Sestamibi has in the past been given to patients following thrombolytic therapy to document reperfusion and assess salvage. However, the factors which affect sestamibi kinetics during reperfusion are not clearly defined. In this study the left circumflex coronary artery was occluded for 2 h in six dogs (group 1) and for 3 h in six dogs (group 2), followed by reperfusion. Five additional dogs were not reperfused (group 3). Sestamibi was administered during reperfusion in groups 1 and 2, and during ongoing occlusion in group 3. Regional myocardial sestamibi activity was monitored for 3 h using miniature implanted radiation detectors and gamma camera imaging. Group 1 dogs had no infarcts, group 2 had moderate infarcts (mean: 13.9%), and group 3 had large infarcts (mean: 25.2%). Three-hour fractional myocardial clearances were significantly greater for reperfused infarcted (group 2) (0.23±0.02 SEM) and for nonreperfused infarcted myocardium (group 3) (0.24±0.02) compared to control (0.10±0.01) and reperfused noninfarcted myocardium (group 1) (0.07±0.02; P<0.01). Quantitative image analysis demonstrated a significant reduction in the left circumflex/left anterior descending count ratios from initial to final scans for group 2 (0.74±0.03 to 0.65±0.03, P<0.05), and a trend towards a reduction in the count ratios from initial to final scans for group 3 (0.38±0.04 to 0.30±0.04; P=0.06). Thus, probederived myocardial sestamibi kinetics following reperfusion do differentiate non-infarcted from infarcted myocardium. Although the detection of accelerated clearance can be demonstrated by quantitative analysis of gamma camera images in dogs, this may be technically difficult in clinical situations. (orig.)

  5. Evaluation of LeVeen-shunt patency using Tc-99m labelled macroaggregated albumin.

    Adil, Allah Rakha; Waqar, Amin

    2005-12-01

    A LeVeen peritoneo-venous shunt is placed for intractable ascites. Determination of obstruction site in the shunt tube is a difficult problem. We describe a simple nuclear medicine method using 111MBq (3mCi) of Technetium-99m labeled macro-aggregated albumin injected intraperitoneally. PMID:16398982

  6. Comparison study among methodologies of planar chromatography for radiochemical control of technetium-99m

    Radiopharmaceuticals are substances that have radioisotopes in their composition. About 95% of the procedures performed in nuclear medicine use radiopharmaceuticals with diagnostic purposes, and the Lyophilized Reagents (LR) labeled with Technetium-99m (99mTc), obtained from 99Mo/99mTc generator, are the most one used. Quality Control represents the set of assays to be performed to assure that the product is adequate to its purpose. An important feature to be evaluated in 99mTc radiopharmaceuticals is the radiochemical purity (% RqP) to quantify free pertechnetate (99mTcO4-) and technetium colloidal (99mTcO2) mainly by paper chromatography (PC), thin layer (TLC) and High Performance Liquid Chromatography (HPLC). The objective of this work was to perform the comparison among the radiochemical control methodologies of LR labeled with 99mTc, described in the United States Pharmacopoeia (USP) and European Pharmacopoeia (EP) and those used by IPEN. 99mTcO4- eluate and DISIDA, DMSA, DTPA, EC, ECD, GHA, MIBI, MDP, PIRO, SAH and Sn Coloidal LR were provided by IPEN-CNEN/SP. TLC-cellulose, TLC-SG.TLC-SG reverse phase, HPTLC-cellulose, HPTLC-SG (Merck) and ITLC-SG (Pall Corporation), W1MM, W3MM, W17M e W31ET (Whatman) chromatographic plates were used. The measurement of the radioactivity was done in a Perkin Elmer Cobra D-5002 gamma counter. LR were labeled to obtain 55,0 MBq mL1 (1,5 mCi mL1) of final radioactive concentration. The %99mTcO4-, %99mTcO2 and % RqP were determined up to 4 hour labeling. From 11 LR, only EC and GHA have no radiochemical control methods in USP and EP. In USP and/or EP, DTPA, MDP, PIRO, SAH and Sn Coloidal methods use ITLC-SG; IPEN uses this chromatography plate in DISIDA, EC, ECD, GHA, PIRO, MIBI and SAH. As ITLC-SG had been out of production (recommended in 40, 70 and 41% of the USP, EP and IPEN methodologies, respectively), it was necessary to search alternatives to replace ITLC-SG plate in the radiochemical control, comparing with HPTLC

  7. Labelling of red blood cells with 99m pertechnetate

    This paper describes a method for labelling red blood cells with 99mTc in vitro, using electrolytically generated stannous ions as the reducing agent for 99mTc-pertechnetate. A labelling of 95% was found. A method for the in vivo labelling of red blood cells is also reported. This involves an injection of a stanno-DTPA-complex followed 20 minutes later by a 99mTc-pertechnetate solution scintillation camera images show more background activity when the in vivo method of labelling is used

  8. (99m)Tc-labeled porphyrin-lipid nanovesicles.

    Lee, Jae-Ho; Shao, Shuai; Cheng, Kenneth T; Lovell, Jonathan F; Paik, Chang H

    2015-01-01

    Porphyrin-lipid nanovesicles (PLN) have been developed with intrinsic capabilities as activatable multimodal photonic contrast agents. Radiolabeling of PLN encapsulating drugs could eventually be able to provide quantitative in vivo information for diagnosing and treating diseases. In this study, we developed (99m)Tc-labeled porphyrin-lipid nanovesicles ((99m)Tc-PLN) as a cargo-encapsulated formulation without significant impact on liposome integrity and encapsulation stability. 50 mM calcein was encapsulated into PLN by probe sonication. The size of the PLN was about 150 nm. The PLN were then reacted with (99m)Tc using SnCl2 dissolved in 1 mM HCl as a reducing agent and incubated for 10 min at 22 °C. The radiolabeling efficiency and stability of (99m)Tc-PLN were evaluated by instant thin-layer chromatography and low-pressure liquid chromatography (LPLC). (99m)Tc labeling was successful with a >92% labeling efficiency. LPLC showed that the liposomal elution peaks of the porphyrin-lipid and the calcein overlapped with the radioactivity elution peak of (99m)Tc-labeled PLN. The (99m)Tc-labeling procedure did not change the size of PLN. Encapsulated calcein remained inert inside PLN. Thus, this work lays out a simple and effective radiolabeling method using SnCl2 in HCl in the preparation of (99m)Tc-PLN. PMID:24963601

  9. Tumour imaging using technetium-99m-citrate

    Sixteen patients with soft tissue malignancy or fibroadenoma of the breast (Group A) were imaged using 99mTc-citrate. Majority of the patients (n=14) has new untreated lesions. Appreciable skeletal uptake of the tracer was serendipitously noticed in all cases. One of these had widespread bone metastases seen almost identically in 99mTc-citrate and 99mTc-MDP studies. Accordingly, 10 patients (Group B) having more than 40 malignant lesions on the bone scan underwent 99mTc-citrate study. In group A, accumulation of the tracer was seen in all malignant breast nodules and axillary lymphnode mass (n=4), medullary carcinoma of the thyroid along with its metastasis and a carcinoid (n=4) and an ovarian malignancy. Uptake and outflow pattern could differentiate fibroadenoma (n=3) from carcinoma of the breast. No significant uptake was seen in liver secondaries (n>10), lymphoma lesions (n=5), papillary carcinoma of thyroid, renal cell and embryonal cell carcinoma. In group B patients, the radiotracer accumulated well in the metastatic lesions while there was distinctly lesser uptake in normal/degenerated joints compared to the bone scan. The study shows potential of the tracer in imaging soft tissue malignancies. Bone scanning with 99mTc-citrate is an interesting possibility since mechanism of its uptake appears to be different to 99mTc-MDP. (author)

  10. Binding of Technetium-99m to plasma proteins: influence on the distribution of Tc-99m phosphate agents

    Plasma protein binding of Tc-99m was assessed in man after injection of various Tc-99m-labeled bone imaging agents. Of the five methods in which plasma proteins were precipitated to determine protein binding no correlation between them could be established. The ammonium sulfate method seemed to correlate well with dialysis filtration. Plasma obtained from patients injected with Tc-99m phosphate compounds was reinjected to rats. The bone uptake in these animals correlated linearly with the unbound activity in the injected plasma. Provided that no protein binding would occur, the bone uptake as well as the urinary excretion proved to be identical for Tc-99m HEDP, MDP, and PPi. Electrophoresis of Tc-99m PPi indicated that the intact complex may be uncharged, whereas at low ligand concentrations uncharged as well as negatively charged Tc-99m species are formed. Better methods are needed, however, to establish the presence of various Tc-99m species and their relative role in the kinetics of these compounds, and plasma protein binding

  11. Effect of light on solution of reduced technetium-99m

    The production of technetium pharmaceuticals involves the reduction of Tc(VII) to Tc(IV), however the chromatographic behaviour of Tc(IV) products suggests re-oxidation to Tc(VII). This is inconsistent with their overall behaviour. This note considers the possibility of a photochemical effect and confirms that light has a significant effect on the behaviour of technetium derivatives studied. (U.K.)

  12. Technetium and rhenium complexes with modified fatty acid ligands 4. Evaluation of two new classes of {sup 99m}Tc-labelled fatty acids as potential tracers for myocardial metabolism imaging

    Heintz, A.; Kropp, J.; Deussen, A. [TU Dresden, Medizinische Fakultaet Carl Gustav Carus (Germany); Jung, C.M.; Spies, H.

    2002-01-01

    {sup 99m}Tc-labelled fatty acids were synthesized according to the '3+1' mixed-ligand approach and investigated as potential tracers for myocardial SPECT diagnostics on the model of the isolated guinea pig heart. The results indicate a low but specific myocardial uptake of the {sup 99m}Tc fatty acid derivatives subject to chain length and structure. (orig.)

  13. Labelling of gentamicin sulphate with99mTc

    The labelling of gentamicin sulphate with99mTc and its optimization is shown. The Quality control of gentamicin sulphate -99mTc, and a study about PH and mass variation of SnCl2 are described. (M.J.C)

  14. Uptake and localization of sup(99m)technetium-methylene-diphosphonate in bone

    The author investigated the uptake and localization of 99m-technetium-methylene-diphosphonate (99m-Tc-MDP) in bone, to develop a sensitive mean for the detection of early osseous disease. In an electrolysis procedure without the presence of contaminating reductants a 99m-Tc-MDP complex is formed with clear bone-seeking properties. The scans performed in experimental animals are comparable in quality with 99m-Tc(Sn)-MDP scans. The uptake of 99m-Tc-MDP is faster and higher than the uptake of reduced hydrolyzed 99m-Tc. Uptake of 99m-Tc(Sn)-MDP in bone can only take place after decomposition of the complex. As 99m-Tc-MDP is taken up as a unit, this may be a better agent to evaluate the osteoblastic activity in the skeleton. (Auth./R.B.)

  15. Study with radio aerosol of DTPA technetium-99 m in individuals with pulmonary disease by amiodarone

    In order to evaluate the role of the clearance of 99 m Technetium chelated to diethylenetriamine-penta-acetate (99 m Tc-DTPA) in amiodarone induced pulmonary disease, 40 individuals were studied in four groups. After spirometry, where a volume-time curve was registered, all individuals inhaled 740 MBq of 99 m Tc-DTPA diluted in 4 ml of saline, for five minutes. Pulmonary images were obtained in a computerized scintillation camera and 9 regions of interest were selected. (author)

  16. Assessment of cerebral perfusion in chronic tobacco users through spect (single photon emission computed tomography) using Tc-99m HMPAO(metastable technetium-99 labelled hexa-methyl propylene amine oxime)

    Objective: To determine an association between chronic tobacco use and changes in cerebral perfusion through semi-quantitative scintigraphic assessment employing metastable Technetium-99 labelled hexa-methyl propylene amine oxime single photon emission computed tomography (Tc-99m HMPAO SPECT). Design: Case-control study. Place and duration of study: The study was conducted at the Department of Medical Sciences, Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamabad, from Oct 2001 to May 2002. Patients and Methods: Regional cerebral perfusion in 48 chronic tobacco users was evaluated, utilising a normal database created by HMPAO brain scans of 20 non-tobacco users. Subjects were classified into chronic tobacco users and non-tobacco users through the use of the smoking index (SI). [Smoking Index = Number of years of tobacco use x Number of cigarettes smoked per day]. SI value of 100 was taken as the cut-off value. Regions of interest (ROIs) were declared hypo perfused or hyper perfused if their percentage perfusion values relative to the average perfusion per pixel of the whole slice under evaluation did not fall within + 2 standard deviation (SD) of the mean regional perfusion in the corresponding ROI, in the normal control group. Result: Chronic tobacco users showed 164 hypo perfused ROIs (6.57%) and 138 hyper perfused ROIs (5.53%) out of 2496 ROIs assessed, whereas the normal controls showed only 15 hypo perfused (1.44%) and 27 hyper perfused (2.60%) ROIs out of 1040 ROIs assessed (P < 0.001). Conclusion: Cerebral perfusion in chronic tobacco users was found to be significantly decreased compared to the non-tobacco users. (author)

  17. The chemistry of 99mTc-labeled radiopharmaceuticals

    The subject of the chemistry of 99mTc-radiopharmaceuticals consists of a collection of bits and pieces of information without a unifying theme. Since the initial impetus to the field of organ imaging was provided by radiochemists, nuclear chemists, and clinician-investigators, using easily prepared 99mTc-compounds from available off-the-shelf ligands, complete chemical characterization was not carried for the 99mTc-radiopharmaceuticals and their metabolites. The influx of coordination, organic, and analytic chemists and their systematic studies clarified some of the structures of these tracers, and promoted the general synthetic methods of a variety of ligands and the corresponding 99mTc-chelates as well as understanding of the nature of their metabolites. Although major developments for organ-imaging radiopharmaceuticals had been made, future studies will result in the simplified methodology of protein-labeling, fine-tuning of the currently available radiopharmaceuticals for higher organ-extraction, and replacement of expensive 123I-labeled tracers with the corresponding 99mTc-tracers. In general, the Tc-complexes are thermodynamically less stable and kinetically more labile than the corresponding Re-complexes. The well established chemistry of Re-compounds, the similarity of Tc-chemistry to that of Re compounds, and structure-activity relationships of a few classes of 99mTc-labeled compounds, may promote the development of new generation of 99mTc-labeled radiopharmaceuticals.69 references

  18. Imaging rheumatoid arthritis specifically with technetium99m CD4-specific (T-helper lymphocytes) antibodies

    CD4 expressing T-lymphocytes are involved in the pathogenesis of rheumatoid arthritis, so the possibility of using radiolabelled CD4-specific antibodies to localise diseased joints was studied. Prospectively six patients with rheumatoid arthritis were investigated in all. Five of them received 200-300 μg of a 555 MBq technetium 99m CD4-specific antibody (MAX.16H5) and were examined with three phase bone scans. Max.16H5 (IgG1) was labelled according to the mercaptoethanol (Schwarz) method. Lumphocytes of one patient were isolated on a Ficoll-Hypaque gradient and labelled with the antibody in vitro. Scans were performed 1.5 h, 4 and 24 h post injection in anterior and posterior views. In all patients, diseased joints could be clearly imaged at as early as 1.5 h. The localisation of the diseased joints correlated (P0.05). According to these data we conclude that 99mTc-labelled CD4-specific antibodies specifically image actively diseased joints in rheumatoid arthritis. (orig.)

  19. 99mTc-HYNIC-derivatized ternary ligand complexes for 99mTc-labeled polypeptides with low in vivo protein binding

    6-Hydrazinopyridine-3-carboxylic acid (HYNIC) is a representative agent used to prepare technetium-99m (99mTc)-labeled polypeptides with tricine as a coligand. However, 99mTc-HYNIC-labeled polypeptides show delayed elimination rates of the radioactivity not only from the blood but also from nontarget tissues such as the liver and kidney. In this study, a preformed chelate of tetrafluorophenol (TFP) active ester of [99mTc](HYNIC)(tricine)(benzoylpyridine: BP) ternary complex was synthesized to prepare 99mTc-labeled polypeptides with higher stability against exchange reactions with proteins in plasma and lysosomes using the Fab fragment of a monoclonal antibody and galactosyl-neoglycoalbumin (NGA) as model polypeptides. When incubated in plasma, [99mTc](HYNIC-Fab)(tricine)(BP) showed significant reduction of the radioactivity in high molecular weight fractions compared with [99mTc](HYNIC-Fab)(tricine)2. When injected into mice, [99mTc](HYNIC-NGA)(tricine)(BP) was metabolized to [99mTc](HYNIC-lysine)(tricine)(BP) in the liver with no radioactivity detected in protein-bound fractions in contrast to the observations with [99mTc](HYNIC-NGA)(tricine)2. In addition, [99mTc](HYNIC-NGA)(tricine)(BP) showed significantly faster elimination rates of the radioactivity from the liver as compared with [99mTc](HYNIC-NGA)(tricine)2. Similar results were observed with 99mTc-labeled Fab fragments where [99mTc](HYNIC-Fab)(tricine)(BP) exhibited significantly faster elimination rates of the radioactivity not only from the blood but also from the kidney. These findings indicated that conjugation of [99mTc](HYNIC)(tricine)(BP) ternary ligand complex to polypeptides accelerated elimination rates of the radioactivity from the blood and nontarget tissues due to low binding of the [99mTc](HYNIC)(tricine)(BP) complex with proteins in the blood and in the lysosomes. Such characteristics would render the TFP active ester of [99mTc](HYNIC)(tricine)(BP) complex attractive as a radiolabeling

  20. (99m)Tc-labeled therapeutic inhaled amikacin loaded liposomes.

    Lee, Jae-Ho; Cheng, Kenneth T; Malinin, Vladimir; Li, Zhili; Yao, Zhengsheng; Lee, Sung-Jin; Gould, Christine M; Olivier, Kenneth N; Chen, Clara; Perkins, Walter R; Paik, Chang H

    2013-12-01

    The radiolabeling of the liposome surface can be a useful tool for in vivo tracking of therapeutic drug loaded liposomes. We investigated radiolabeling therapeutic drug (i.e. an antibiotic, amikacin) loaded liposomes with (99m)Tc, nebulization properties of (99m)Tc-labeled liposomal amikacin for inhalation ((99m)Tc-LAI), and its stability by size exclusion low-pressure liquid chromatography (LPLC). LAI was reacted with (99m)Tc using SnCl2 dissolved in ascorbic acid as a reducing agent for 10 min at room temperature. The labeled products were then purified by anion exchange resin. The purified (99m)Tc-LAI in 1.5% NaCl solution was incubated at 4 °C to assess its stability by LPLC. The purified (99m)Tc-LAI was subjected to studies with a clinically used nebulizer (PARI eFlow®) and the Anderson Cascade Impactor (ACI). The use of ascorbic acid at 0.91 mM resulted in a quantitative labeling efficiency. The LPLC profile showed that the liposomal peak of LAI detected by a UV monitor at both 200 nm and 254 nm overlapped with the radioactivity peak of (99m)Tc-LAI, indicating that (99m)Tc-LAI is suitable for tracing LAI. The ACI study demonstrated that the aerosol droplet size distribution determined gravimetrically was similar to that determined by radioactivity. The liposome surface labeling method using SnCl₂ in 0.91 mM ascorbic acid produced (99m)Tc-LAI with a high labeling efficiency and stability that are adequate to evaluate the deposition and clearance of inhaled LAI in the lung by gamma scintigraphy. PMID:23879241

  1. Preparation of a pure [sup 99m]Tc-F(ab')[sub 2] radioimmunoconjugate by direct labeling methods

    Griffiths, G.L.; Jones, A.L.; Hansen, H.J. (Immunomedics Inc., Morris Plains, NJ (United States)); Goldenberg, D.M. (Center for Molecular Medicine and Immunology, Newark, NJ (United States))

    1994-05-01

    Intact IgG and Fab' can be labeled directly with [sup 99m]Tc to give quantitative incorporation of radioactivity into the protein. With F(ab')[sub 2] the reductive conditions yield a mixture of [sup 99m]Tc-F(ab')[sub 2] and [sup 99m]Tc-Fab'. We now report a direct labeling method to produce only [sup 99m]Tc-F(ab')[sub 2] in quantitative yield and contaminated with [sup 99m]Tc-Fab'. The properties, stability and biodistribution of the [sup 99m]Tc-F(ab')[sub 2] have been compared to [sup 99m]Tc-Fab'. This new technology will allow us to compare technetium direct-labeled IgG, F(ab')[sub 2] and Fab' derivatives of the same antibody for radioimmunodetection. (author).

  2. A new technology of technetium-99m production for medicine imaging

    Dovbnya, A.N.; Dikiy, N.P.; Medvedyeva, Ye.P.; Tur, Yu.D.; Uvarov, U.L. [National Science Center Kharkov Inst. of Physics and Technology, Kharkov (Ukraine)

    1998-07-01

    Technetium-99m provides now up to 90% of medical analysis using gamma-scintigraphy method. The parent isotope {sup 99} Mo is produced mainly in fission reactors, that is rather technically complicated and ecologically unwonted. The report contains a short description of new approach to {sup 99m} Tc production problem using irradiation of Mo-target with mixed e, n, {gamma}-radiation of electron accelerator and extraction of {sup 99m} Tc by electrolysis. Medical test of {sup 99m} Tc based radiopharmaceutical thus produced their high isotope purity. (author)

  3. Which role for Technetium-99m radiopharmaceuticals in the age of molecular imaging?

    Full text: Molecular imaging is a new paradigm that is currently modifying our common approach to the study of fundamental biological processes. In this representation, the behaviour of a single cell in a living tissue is thought to be the result of the entanglement of a number of basic biochemical pathways, which are tightly grouped together to form a final biological network extended through the whole organism. Nuclear imaging is a subfield characterized by the use of radiolabeled single-molecule probes, which are specifically designed for monitoring selected biomolecular processes belonging to a particular biological network. After the advent of a new generation of small animal scanners having a submillimiter resolution, Single Photon Emission Computed Tomography (SPECT) is receiving a growing interest brought about by the observation that, unlike Positron Emission Tomography, there is no intrinsic physical limit to the resolution that could be achieved when single-photon emitting radiolabeled probes are employed. Technetium-99m is still recognized as the γ-emitting radionuclide having the most ideal nuclear properties and, therefore, 99mTc radiopharmaceuticals may play a significant role in molecular imaging, particularly if novel categories of tracers exhibiting superior imaging characteristics will be developed using advanced chemical methods. At present, a number of fundamental biological processes can be successfully monitored using 99mTc agents, and they will be shortly reviewed in this paper. Examples range from the use of [99mTcO4]- for monitoring gene expression, to the labeling of a large number of different peptides targeting receptors expressed in various disease states and processes such as tumour proliferation, inflammation, angiogenesis and formation of atherotic plaques. Problems and perspectives in the design of imaging agents for the central nervous system will also be discussed. (author)

  4. Comparison of the accumulation and efflux kinetics of technetium-99m sestamibi and technetium-99m tetrofosmin in an MRP-expressing tumour cell line

    The potential clinical use of technetium-99m labeled sestamibi (Tc-MIBI) and tetrofosmin (Tc-Tfos) to image tumours is currently being evaluated. In this study, the accumulation and efflux of Tc-MIBI and Tc-Tfos in the nasopharyngeal carcinoma cell line CNE-1 were examined in the presence or absence of various inhibitors of P-glycoprotein (PGP) and/or multidrug resistance associated protein (MRP) activity [GG918, PSC833, verapamil (Vrp), cyclosporin A (CsA) and buthionine sulfoximine (BSO)]. Reverse-transcriptase polymerase chain reaction analysis and immunodetection of the CNE-1 cells detected expression of MRP, MRP1 and MRP2 but not PGP. Tc-MIBI and Tc-Tfos accumulation was increased (P2 times greater than for Tc-MIBI). However, no qualitative differences in inhibitors were seen between Tc-MIBI and Tc-Tfos. These results suggest that both Tc-MIBI and Tc-Tfos are substrates for the MRP transporter and that PSC833, Vrp, CsA and BSO but not GG918 can inhibit MRP activity. These results indicate that Tc-MIBI and Tc-Tfos may be suitable imaging agents for detecting MRP-mediated drug resistance in human cancers. (orig.)

  5. Technetium 99m pertechnetate scans in congenital hypothyroidism

    Goiters are rarely palpable in infants with congenital hypothyroidism except in the case of maternal ingestion of iodide. The presence or absence of glandular tissue is, however, important for genetic and prognostic counseling and for acceleration of diagnosis in other affected siblings. The detection of thyroid tissue by /sup 99m/Tc pertechnetate scans in a significant number of our patients heretofore considered athyreotic establishes that physical findings and traditional laboratory data are not adequate to determine whether or not thyroid tissue is present

  6. The primary application of 99mTc labeled glucose: 99mTc-EC-DG in tumor imaging

    Purpose: 18F-FDG glucose metabolic imaging plays an important role. in. clinical, practice. But, because of the expensive price of PET machine and cyclotron, 18F-FDG imaging is not easy to access and has difficult availability. Now the research of technetium labeled glucose is a hotspot in nuclear medicine imaging agent development. The Purpose of this study is to primarily study the clinical application in tumor imaging of 99mTc labeled glucose: 99mTc-EC-DG. Method: EC-DG was synthesized according to a known procedure (Yang et al, Radiology 226: 465, 2003). Labeling of 99mTc-ECDG was achieved by means of adding the required amount of ECDG and tin (II) chloride to the pertechnetate. Radiochemical purity was assessed at radio-thin-layer chromatography, with 1 mol/L of ammonium acetate plus methanol (4:1) as the eluant. 18 patients (9 cases of lung cancer, 1 lymphoma, 1 hepatic cell cancer, 1 recurrence of gastric cancer, 1 recurrence of thyroid cancer, 1 recurrence of colon cancer, 1 lung metastasis of thyroid cancer, 1 pneumonia, 1 tuberculosis and 1 inflammation of breast) fasted 6 hours and then underwent the 99mTc-EC-DG imaging after the injection of 25 mci 99mTc-EC-DG intravenously, the planar and tomographic imaging was acquired 2 hours and 4 hours after the injection, and the ratio of tumor to normal tissue was calculated. 4 of the 15 cases of malignant tumor were performed 18F-FDG imaging contrastively. The machine used in this study is Axis dual-headed coincidence SPECT of PICKER company, and iterative reconstruction is used in data process. Result: brain is not imaged and kidneys are clearly imaged in 99mTc-EC-DG imaging, the blood clearance of 99mTc-EC-DG is slower than that of 18F-FDG, the blood pool of heart and big blood vessel is seen at the time of 2 hours after the injection of 99mTc-ECDG, and still visible at 4 hours, the uptake of muscle is low. 14 cases of malignant tumor had positive imaging result (14/15), T/N ratio of 2 hours is 1.36-5.64 (2

  7. Scintigraphy with technetium dimercaptosuccinic acid (99m Tc DMSA)

    Renal uptake of 99m Tc DMSA was used to evaluate the renal function of 16 healthy subjects (controls) and 115 patients with various urinary tract diseases. Scintigraphic examination was carried out 6 hours after an intravenous injection of the product. In the 16 controls Tc DMSA uptake was 25.7+-2.48% in the right kidney and 24.4+-2.86% in the left kidney. In 36 patients with one single hypertrophied kidney, there was a correlation (r=0.850) between creatinine clearance and Tc DMSA uptake, which was higher than in normal subjects (39.23+-9.9%). In the group of 68 patients with unilateral (31) or bilateral (37) renal disease, a significant correlation (r=0,725) was observed between kidney-to-kidney ratios of urea clearance and Tc DMSA uptake, so that renal impairment could be quantified. Quantitative scintigraphy did not appear to be of assistance in the remaining 11 patients with obstructive uropathy, as it overestimated renal function. The results obtained with 99 m Tc DMSA scintigraphy should be helpful in choosing between nephrectomy and conservative surgery and in assessing the degree of compensatory hypertrophy in single kidneys

  8. Advances in 99mTc-labeling of antibodies

    Several methods have been developed to label antibodies with 99mTc. Direct labeling results in 99mTc binding to multiple sites of various affinities that are often weaker than the binding to strong chelating agents. Attempts to overcome this disadvantage involve conjugation of strong chelating agents to the antibodies. While stability is usually enhanced, this approach suffers from alteration of antibody properties as well as non-specific binding of 99mTc to the antibody instead of to the conjugation chelating agent. This has been of concern for studies with DTPA as the chelating agent. In this study the loss of 99mTc by N2S2 challenge shows that a fraction to the 99mTc is nonspecifically bound to the antibody. An advantage of the approach of labeling antibodies containing a bifunctional chelating agent is the simplicity of the labeling procedure and the apparent high yields that in reality are the sum of chelating agent and non-specifically bound radioactivity. The last approach described in our work of conjugation of a preformed chelate has advantages of characterizable 99mTc complex chemistry and conjugation by standard protein derivatization chemistry. Slow chelation kinetics can be overcome in the small molecule stage and then conjugation performed under mild conditions with respect to the antibody of fragments. This approach, however, suffers from greater complexity of the labeling process including multiple steps, purifications and non-quantitative yields. The use of ligands for 99mTc in which the complexes are of high stability and predictable chemistry is likely to result in eventual optimal labeling technologies. Processes which are non-specific may work in some cases, but are likely to present difficulties in optimization and general applicability from antibody to antibody. (orig.)

  9. Towards kit formulation of 99mTc labelled somatostatin receptor binding peptides of high specific activity for tumour localization

    The project aimed to develop 99mTc octreotide analogue for use in nuclear oncology. Several attempts to label SRIF analogues with 99mTc have used a direct labelling approach but, for this project, HYNIC was chosen as a technetium ligand. A comparison of two different SRIF analogues designed for high specific activity labelling with 99mTc was done. HYNIC-Octreotide and HYNIC-TOC were prepared and a kit formulation that can be labelled conveniently is currently being studied in a clinical setting. (author)

  10. Direct {sup 99m}Tc labeling of Herceptin (trastuzumab) by {sup 99m}Tc(I) tricarbonyl ion

    Chen, W.-J.; Yen, C.-L.; Lo, S.-T.; Chen, K.-T. [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lo, J.-M. [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan (China)], E-mail: jmlo@mx.nthu.edu.tw

    2008-03-15

    By simply incubating Herceptin (trastuzumab) with [{sup 99m}Tc(CO){sub 3}(OH{sub 2}){sub 3}]{sup +} ion in saline, a significant yield of {sup 99m}Tc-labeled trastuzumab was found to be achievable. The effective labeling may be based on that trastuzumab is inherent with endogenous histidine group to which {sup 99m}Tc(I) tricarbonyl ion can be strongly bound. For practical {sup 99m}Tc labeling processing, trastuzumab was purified beforehand from the commercial product, Herceptin (Genentech) via size exclusion chromatography to remove the excipient, {alpha}-histidine and a high-labeled yield could be obtained by incubating the purified trastuzumab with [{sup 99m}Tc(CO){sub 3}(OH{sub 2}){sub 3}]{sup +}. Retention of bioactivity of the {sup 99m}Tc(I)-labeled trastuzumab was validated using a cell binding test.

  11. Direct 99mTc labeling of Herceptin (trastuzumab) by 99mTc(I) tricarbonyl ion

    By simply incubating Herceptin (trastuzumab) with [99mTc(CO)3(OH2)3]+ ion in saline, a significant yield of 99mTc-labeled trastuzumab was found to be achievable. The effective labeling may be based on that trastuzumab is inherent with endogenous histidine group to which 99mTc(I) tricarbonyl ion can be strongly bound. For practical 99mTc labeling processing, trastuzumab was purified beforehand from the commercial product, Herceptin (Genentech) via size exclusion chromatography to remove the excipient, α-histidine and a high-labeled yield could be obtained by incubating the purified trastuzumab with [99mTc(CO)3(OH2)3]+. Retention of bioactivity of the 99mTc(I)-labeled trastuzumab was validated using a cell binding test

  12. Technetium-99m hexamethylpropylene amine oxime leucocyte scintigraphy in the differential diagnosis of cerebral abscesses.

    Spinelli, F; Sara, R; Milella, M; Ruffini, L; Sterzi, R; Causarano, I R; Sberna, M

    2000-01-01

    The diagnosis of brain abscess is often difficult, as the clinical symptoms are not specific. Computed tomography (CT) and magnetic resonance imaging (MRI) are highly sensitive, but different cerebral lesions, especially neoplasms, can have the same ring-like contrast enhancement. Brain abscess is a severe illness requiring rapid diagnosis to choose the most appropriate therapy. Technetium-99m hexamethylpropylene amine oxime (HMPAO)-labelled leucocyte scintigraphy is commonly used to detect an inflammatory process. The aim of this study was to present the results obtained with leucocyte scintigraphy in 65 patients with intracranial mass lesions and clinical findings compatible to or suggestive of brain abscess. The final diagnosis, based on surgery, clinical findings and stereotatic puncture, was brain abscess in 17 patients, primary brain neoplasm in 22, brain metastasis in 16, lymphoma in 2, cysticercosis in 2, hematoma in 2 and cerebral infarction in 4. 99mTc-HMPAO leucocyte scintigraphy was positive in all abscess cases. The scan was negative in the rest of the patients examined, with the exception of one lesion, which was finally diagnosed as a tumour (1 false-positive). All patients who did not have false-negative scans were treated with steroids. The sensitivity, specificity and diagnostic accuracy of leucocyte scintigraphy was 100%, 97.8% and 98.4%, respectively. In conclusion, in our experience, leucocyte scintigraphy is a valuable aid in the differential diagnosis between abscess and neoplasm. PMID:10654146

  13. Technetium-99m hexamethylpropylene amine oxime leucocyte scintigraphy in the differential diagnosis of cerebral abscesses

    The diagnosis of brain abscess is often difficult, as the clinical symptoms are not specific. Computed tomography (CT) and magnetic resonance imaging (MRI) are highly sensitive, but different cerebral lesions, especially neoplasms, can have the same ring-like contrast enhancement. Brain abscess is a severe illness requiring rapid diagnosis to choose the most appropriate therapy. Technetium-99m hexamethylpropylene amine oxime (HMPAO)-labelled leucocyte scintigraphy is commonly used to detect an inflammatory process. The aim of this study was to present the results obtained with leucocyte scintigraphy in 65 patients with intracranial mass lesions and clinical findings compatible to or suggestive of brain abscess. The final diagnosis, based on surgery, clinical findings and stereotatic puncture, was brain abscess in 17 patients, primary brain neoplasm in 22, brain metastasis in 16, lymphoma in 2, cysticercosis in 2, hematoma in 2 and cerebral infarction in 4. 99mTc-HMPAO leucocyte scintigraphy was positive in all abscess cases. The scan was negative in the rest of the patients examined, with the exception of one lesion, which was finally diagnosed as a tumour (1 false-positive). All patients who did not have false-negative scans were treated with steroids. The sensitivity, specificity and diagnostic accuracy of leucocyte scintigraphy was 100%, 97.8% and 98.4%, respectively. In conclusion, in our experience, leucocyte scintigraphy is a valuable aid in the differential diagnosis between abscess and neoplasm. (orig.)

  14. Technetium-99m hexamethylpropylene amine oxime leucocyte scintigraphy in the differential diagnosis of cerebral abscesses

    Spinelli, F.; Sara, R.; Milella, M.; Ruffini, L. [Dept. of Nuclear Medicine, Niguarda Ca' Granda Hospital, Milan (Italy); Sterzi, R.; Causarano, I.R. [Dept. of Neurology, Niguarda Ca' Granda Hospital, Milan (Italy); Sberna, M. [Dept. of Neuroradiology, Niguarda Ca' Granda Hospital, Milan (Italy)

    2000-01-01

    The diagnosis of brain abscess is often difficult, as the clinical symptoms are not specific. Computed tomography (CT) and magnetic resonance imaging (MRI) are highly sensitive, but different cerebral lesions, especially neoplasms, can have the same ring-like contrast enhancement. Brain abscess is a severe illness requiring rapid diagnosis to choose the most appropriate therapy. Technetium-99m hexamethylpropylene amine oxime (HMPAO)-labelled leucocyte scintigraphy is commonly used to detect an inflammatory process. The aim of this study was to present the results obtained with leucocyte scintigraphy in 65 patients with intracranial mass lesions and clinical findings compatible to or suggestive of brain abscess. The final diagnosis, based on surgery, clinical findings and stereotatic puncture, was brain abscess in 17 patients, primary brain neoplasm in 22, brain metastasis in 16, lymphoma in 2, cysticercosis in 2, hematoma in 2 and cerebral infarction in 4. {sup 99m}Tc-HMPAO leucocyte scintigraphy was positive in all abscess cases. The scan was negative in the rest of the patients examined, with the exception of one lesion, which was finally diagnosed as a tumour (1 false-positive). All patients who did not have false-negative scans were treated with steroids. The sensitivity, specificity and diagnostic accuracy of leucocyte scintigraphy was 100%, 97.8% and 98.4%, respectively. In conclusion, in our experience, leucocyte scintigraphy is a valuable aid in the differential diagnosis between abscess and neoplasm. (orig.)

  15. Automation drying unit molybdenum-zirconium gel radioisotope production technetium-99M for nuclear medicine

    Full text : Since 2001 the Institute of Nuclear Physics of the Republic of Kazakhstan has began production of radiopharmaceutical based on technetium-99m from irradiated reactor WWR-K of natural molybdenum, which allows to obtain a solution of technetium-99m of the required quality and high volume activity. In 2013 an automated system is started, which is unique and urgent task is to develop algorithms and software in Python, as well as the manufacture of certain elements of technological systems for automated production

  16. Somatostatin analogues labelled with 99mTc

    The aim of the present work was to study the biological and radiochemical behaviour of two somatostatin analogues, the RC-160 and Tyr3Octreotide(TOC) peptides when labelling with 99mTc by two methods: direct and indirect using S-benzoyl- mercaptoacetyl triglycine (MAG-3) and hydrazinonicotinamide (HYNIC) as chelating agents. RC-160 was labelled with 125I (30% labelling yield) in order to examine its receptor specificity and to study the biodistribution in normal animals. A total binding of 30% and a non specific binding lower than 10% was obtained. On the other hand, the RC-160 was labelled with 99mTc by a direct method (70% labelling yield), using sodium ascorbate and dithionite in order to reduce the peptide and 99mTc, respectively. The synthesis of RC-160 with S-benzoyl MAG-3 and TOC with HYNIC, for labelling with 99mTc are also described. The conjugates were prepared on a small scale and labelled with the radionuclide using tricine as co-ligands for HYNIC conjugates. Chromatographic studies were performed using HPLC system and radiochemical purities higher than 75% and 95% were obtained respectively. Biodistributions studies in normal Wistar rats were performed and results were correlated with chromatographic and protein binding properties. Lower lipophilicity of the labelled conjugates resulted in a higher renal excretion. HYNIC-TOC complex showed promising results when labelling with 99mTc using tricine as co-ligand although higher stability should be found for ternary co-ligands compared to tricine. (author)

  17. Labelling polypeptide with 99mTc and bioactivity get back

    A method for labelling polypeptide (insulin) with technetium-99 (99mTc) was established without marked loss of biological activity. Following reduction of intrinsic disulfide bonds by mercaptoethanol and purification on a Sephadex G50 column, the polypeptide was labelled with 99mTc by trans-chelation from methylene diphosphonate (MDP). 99mTc labelled insulin was identified by thin layer chromatography (TLC) and the change of blood sugar of mice injected, their hypo-glycemic shock symptom was also observed. Six hours after labelling, the dissociation of labelled insulin was only 3%, From then on to 24 h, there was no more dissociation. The blood sugar concentration of mice injected with the mercaptoethanol-reduced insulin was (5.0 +- 3.2) μmol·L-1, while those injected with the original insulin was (1.4 +- 1.2) μmol·L-1, the difference was significant (Q test, p -1 for the labelled insulin, and was about the same with that for the original insulin. The labelling efficiency was 74.31% for the labelled insulin, whereas the original insulin cannot be labelled with 99mTc. The result suggests that while disulfide bonds of polypeptide were reduced by mercaptoethanol, it became free sulfhydryl group, and its bioactivity descended. Then free sulfhydryl group was chelated with 99mTc under mild condition, re-establishing the disulfide bond, therefore, the bioactivity came back. The 99mTc-labelled insulin was stable during 24 h

  18. Labeling polypeptide with 99mTc and bioactivity get back

    2001-01-01

    A method for labeling polypeptide(insulin) with technetium-99(99mTc) was established without marked loss of biological activity. Following reduction of intrinsic disulfide bonds by mercaptoethanol and purification on a Sephadex G50 column,the polypeptide was labeled with 99mTc by transchelation from methylene diphosphonate (MDP). 99mTc labeled insulin was identified by thin layer chromatograph (TLC)and the change of blood sugar of mice injected, their hypoglycemic shock symptom was also observed. Six hours after labeling, the dissociation of labeled insulin was only 3%,From then on to 24h, there was no more dissociation. The blood sugar concentration of mice injected with the mercaptoethanol-reduced insulin was (5.0±3.2)μmol·L-1, while those injected with the original insulin was (l.4±l.2)μmol·L-1, the difference was significant(Q test, p<0.01). Blood sugar concentration of the mice was 0.3±0.2μmol·L-1for the labeled insulin, and was about the same with that for the original insulin.The labeling efficiency was 74.31% for the labeled insulin, whereas the original insuin cannot be labeled with 99mTc. The result suggests that while disulfide bonds of polypeptide were reduced by mercaptoethanol, it became free sulfhydryl group, and its bioactivity descended. Then free sulfhydryl group was chelated with 99mTc under mild condition, restablishing the disulfide bond, therefore, the bioactivity came back.The 99mTc-labeled insulin was stable during 24 h.

  19. Technical problems associated with the production of technetium Tc 99m tin(II) pyrophosphate kits

    The amount of tin(II) required for adequate reduction, complexation, and stability of technetium Tc 99m pertechnetate in radiopharmaceutical kits, and methods of preventing the loss of tin(II) during formulation of these lyophilized kits are investigated. Tin(II) loss from stannous chloride solutions was studied under several conditions, including room air versus nitrogen atmospheres, during vial filling in a laminar-flow hood with samples frozen on dry ice versus samples at room temperature, during lyophilization, and during storage under refrigerated, ambient, and elevated temperatures. Various amounts of stannous chloride, ranging from 5 to 1000 microgram/ml, were used in formulating sodium pertechnetate Tc 99m kits containing 100 mCi technetium Tc 99m and 0.4 microgram total technetium. Samples were removed at various times; hydrolyzed technetium, pertechnetate, and technetium Tc 99m pyrophosphate were isolated on instant thin-layer chromatography-silica gel and quantified with a scintillation counter. The time necessary to deoxygenate distilled water by nitrogen purging was measured. Several sources of stannous chloride were assayed for tin(II) content. Tin(II) loss occurs rapidly in solution (15% in one hour) unless continuously protected with nitrogen, and during vial filling in a laminar-flow hood unless frozen with dry ice. No substantial loss of tin(II) was detected during lyophilization or during storage of lyophilized product at any of the three temperatures. A minimum of 400 microgram tin(II) was required to provide 90% technetium Tc 99m pyrophosphate at six hours after preparation. Adequate deoxygenation of small quantities (450 ml) of water was accomplished in less than one hour. Some stannous chloride salts were highly oxidized in the dry state, and only high-purity elemental tin wire gave acceptable yields of tin

  20. 3. Congress of the SA Society of nuclear medicine: Technetium-99m technology

    The Atomic Energy Corporation of SA Limited have been engaged in the manufacture of radioisotopes since 1967, shortly after the SAFARI-1 reactor at Pelindaba was commissioned. Since then the use of radioisotopes in South Africa has grown rapidly and at present 95% of the in vivo diagnostic radioisotopes (radiopharmaceuticals) utilized in nuclear medicine are manufactured locally. Because radioisotopes are applied mainly in sophisticated chemically or mechanically processed forms, production requires not only a skilled production team, but also the appropriate facilities for the manufacture of high-quality products which comply with the necessary safety standards. Compliance with such standards is especially important for the routine production of radiopharmaceuticals for use in nuclear medicine. Over the past 20 years technetium-99m has achieved a dominant position among the diagnostic tools in modern nuclear medicine.The scope of nuclear medicine is expanding continuously and its future lies primarily in the development of new organspecific technetium-99m radiodiagnostic agents. Many improvements and changes have been made to Tc-99m generators, the major source of Tc-99m, since they were introduced to nuclear medicine in the late 1950's. The new Peltek-F sterile Tc-99m generator developed by the Isotope Production Centre is a symbol of progress made. In order to commemorate the launching of the new Peltek-F technetium-99m generator during August 1988 it was decided to publish six papers that were presented at the Third Congress of the Society of Nuclear Medicine held at Bloemfontein during the period 15 - 17 August 1988 by members of the Isotope Production Centre. This will serve as a useful reference on various aspects of technetium-99m technology and will stimulate the use of this product as well as new research in this field

  1. Liver uptake of pentavalent technetium-99m dimercaptosuccinic acid in hyperthyroid patients

    Aim: Pentavalent technetium-99m dimercaptosuccinic acid is a tumor imaging agent. That accumulates in the medullary carcinoma of the thyroid, soft -tissue tumors and bone metastasis. Physical uptake has been evidenced in the kidneys, nasal mucosa and blood pool, such as in the heart or vessels. There is no specific localization of technetium-99m (V) DMSA in the liver. In this study, we report on our early experience of diffuse liver uptake of Tc-99m (V) DMSA in 21 patients (mean 54 years, 8 female and 13 men) with diffuse and toxic nodular hyperthyroidism with no pathologic correlation of liver. Materials and Methods: In 21 patients (mean 54 years, 8 female and 13 men) with hyperthyroidism were done 3 hours after injection of approximately 555 MBq Tc-99m (V) DMSA whole body scintigraphy with a single and two headed gamma camera with low energy all purpose collimator for planar imaging. Tc- 99m (V) DMSA was prepared from a DMSA kit with an additional 200 microliter of 7 % sodium bicarbonate solution reconstituted with approximately 2 ml of 740 MBq Tc -99m pertechnetate. Results: All patients had diffuse liver uptake of Tc -99m (V) DMSA and no pathological uptake other sites of their body. Conclusion: Our study clearly showed diffuse increased liver uptake of Tc -99m (V) DMSA in hyperthyroid patients with unknown mechanism. We think the diffuse liver uptake of Tc-99m (V) DMSA in the hyperthyroid patients may offer disadvantage for detecting liver tumors with Tc - 99m (V) DMSA in this patient group

  2. Comparison of the accumulation and efflux kinetics of technetium-99m sestamibi and technetium-99m tetrofosmin in an MRP-expressing tumour cell line

    Utsunomiya, K.; Su, Z.-F.; Ichise, M. [Nuclear Medicine, Mount Sinai Hospital, University of Toronto, Ont. (Canada); Ballinger, J.R. [Nuclear Medicine, Addenbrooke' s Hospital, Cambridge University, Cambridge (United Kingdom); Piquette-Miller, M.; Tang, W. [Faculty of Pharmacy, University of Toronto, 19 Russell Street, Toronto, ON (Canada); Rauth, A.M. [Division of Experimental Therapeutics, Princess Margaret Hospital, Ontario Cancer Institute, ON (Canada)

    2000-12-01

    The potential clinical use of technetium-99m labeled sestamibi (Tc-MIBI) and tetrofosmin (Tc-Tfos) to image tumours is currently being evaluated. In this study, the accumulation and efflux of Tc-MIBI and Tc-Tfos in the nasopharyngeal carcinoma cell line CNE-1 were examined in the presence or absence of various inhibitors of P-glycoprotein (PGP) and/or multidrug resistance associated protein (MRP) activity [GG918, PSC833, verapamil (Vrp), cyclosporin A (CsA) and buthionine sulfoximine (BSO)]. Reverse-transcriptase polymerase chain reaction analysis and immunodetection of the CNE-1 cells detected expression of MRP, MRP1 and MRP2 but not PGP. Tc-MIBI and Tc-Tfos accumulation was increased (P<0.0001) and efflux decreased (P<0.05) in the presence of BSO, CsA, Vrp and PSC833 but not GG918, which is a specific inhibitor of PGP. The absolute accumulation of Tc-MIBI was approximately twofold higher than that seen with Tc-Tfos, whereas the addition of inhibitors caused a much greater suppression of Tc-Tfos transport (>2 times greater than for Tc-MIBI). However, no qualitative differences in inhibitors were seen between Tc-MIBI and Tc-Tfos. These results suggest that both Tc-MIBI and Tc-Tfos are substrates for the MRP transporter and that PSC833, Vrp, CsA and BSO but not GG918 can inhibit MRP activity. These results indicate that Tc-MIBI and Tc-Tfos may be suitable imaging agents for detecting MRP-mediated drug resistance in human cancers. (orig.)

  3. Study of the viability of technetium-{sup 99m} labeling of whole antimyosin antibody and its fragment: development of radiopharmaceutical for cardiac survey; Estudo da viabilidade da marcacao com tecnecio-99m do anticorpo antimiosina integro e seu fragmento: desenvolvimento de radiofarmaco para avaliacao cardiaca

    Carvalho, Guilherme Luiz de Castro

    2007-07-01

    In the acute myocardium infarction, the myocytes cell membrane loses its integrity, allowing the influx of extracellular macromolecules such as circulating antibody into the damaged cell. The use of the specific antibodies against cardiac myosin labeled with {sup 99m}Tc allows to determine the localization and extension of myocardial infarction. The purpose of this work was to study the viability of labeling of the antimyosin monoclonal antibody and its fragment F(ab')2 with {sup 99m}Tc. Because of the high cost of antimyosin antibody, others antibodies were used to optimize the methodology and the best condition was used for antimyosin antibody. The intact antibody was cleaved by pepsin to produce F(ab'){sub 2} fragment. The F(ab'){sub 2} and the intact antibody were reduced by treatment with Dithiothreitol (DTT) and 2-Mercaptoethanol (2-ME) and labeled with {sup 99m}Tc by direct method. Different concentrations of reductant, mixing conditions and incubation times were studied. In the standard condition, incubation at molar ratio 1:1000 (antibody:reducing agent) at room temperature for 30 minutes with continuous rotation (850 rpm), 13.28 - SH groups were formed per molecule. It was studied the influence of p H, of the concentration of stannous chloride (Sn{sup 2+}) and incubation time in the labeling condition. The better radiochemical yield (90.06 +- 1.53%) was obtained using 2.5 {mu}g of Sn{sup 2+} in p H 4.5 for 60 minutes. The labeling of the fragment F(ab'){sub 2} did not present satisfactory results because of the low yield of the digestion. After purification by PD-10, the biodistribution study was performed and showed that the intact antimyosin antibody labeled with {sup 99m}Tc presented fast kinetic compatible with the biodistribution of an intact antibody labeled with {sup 99m}Tc. Scintigraphy image of the animal with myocardial infarction was obtained and compared with the image of a normal animal. The studies allow to conclude that

  4. Generator and method for the production of technetium-99m from molybdenum-99

    A molybdenum-99/technetium-99m generator utilizing a multiple pH alumina support medium is disclosed. The elution of this generator results in a minimum of low-yield problems. Two extraction columns of controlled but different pH are used in series. The pH difference is at least 0.5

  5. Technetium-99m-sestamibi/pertechnetate subtraction scintigraphy vs ultrasonography for preoperative localization in primary hyperparathyroidism

    Berczi, C.; Lukacs, G.; Balazs, G. [Department of Surgery, University of Debrecen (Hungary); Mezosi, E.; Bajnok, L. [1. Department of Internal Medicine, University of Debrecen (Hungary); Galuska, L.; Varga, J. [Department of Nuclear Medicine, University of Debrecen (Hungary)

    2002-03-01

    A prospective study was performed to evaluate the efficacy of technetium-99m-sestamibi and technetium-99m-pertechnetate subtraction scanning and US for imaging parathyroid glands in primary hyperparathyroidism. Sixty-three patients were surgically treated for primary hyperparathyroidism (HPT). Preoperative scintigraphy and US were performed in all cases. Bilateral neck exploration was carried out on each patient. Results of radionuclide studies and US were compared with surgical and histological findings. In 57 patients with primary HPT the radionuclide scanning gave true-positive results. Four false-negative and two false-positive scintigrams were obtained. The sensitivity and the positive predictive value (PPV) of scintigraphy were 93 and 97%, respectively. Forty-one cases were correctly localized by the US. Seventeen US results were false negative and five were false positive. The sensitivity and the PPV for US were 71 and 89%, respectively. There was a statistically significant difference between the sensitivity of the scintigraphy compared with the US (p=0.001). Sensitivities of radionuclide scans and US were higher for adenomas (100 and 83%) than for hyperplastic glands (75 and 40%). The sensitivity of technetium-99m-sestamibi and technetium-99m-pertechnetate subtraction scintigraphy was significantly higher compared with US. This sensitive method could help surgeons in performing a rapid and directed parathyroidectomy. (orig.)

  6. Mechanism of localization of /sup 99m/Tc-labeled pyrophosphate and tetracycline in infarcted myocardium

    The gross and subcellular localizations of /suJm/Tc-labeled pyrophosphate and tetracycline in myocardial infarcts were studied in a rabbit model. Experiments utilizing double-nuclide labeling were carried out using a useful mapping technique. Concentration of the various chelates decreases in an expected manner from the center of the infarcted area toward its periphery, but it is higher near the epicardial surface than toward the endocardium. Technetium-99m-pyrophosphate is concentrated in the same infarcted areas as 45Ca ion or 32P-pyrophosphate, but to a much greater degree. The uptake is dependent on both the degree of necrosis and residual blood flow. Gel filtration experiments with rabbit serum indicate that /sup 99m/Tc-tagged pyrophosphate, tetracycline, and diphosphonate are mainly protein-bound, whereas 32P-pyrophosphate is not. Subcellular localization studies show that /sup 99m/Tc-tetracycline and /sup 99m/Tc-pyrophosphate are bound primarily to soluble protein, and only a small fraction is associated with nuclei, mitochondria, and microsomes. The uptake of technetium chelates in myocardial infarcts may be due to the formation of polynuclear complexes with denatured macromolecules rather than to the deposition of calcium in mitochondria

  7. Demonstration of reperfusion after thrombolysis with technetium-99m isonitrile myocardial imaging

    Technetium-99m isonitrile myocardial perfusion imaging was employed in a patient undergoing thrombolytic therapy with recombinant tissue plasminogen activator for acute anteroseptal myocardial infarction. Technetium-99m isonitrile does not demonstrate significant myocardial redistribution after intravenous injection. The imaging agent was administered in the emergency room, prior to the initiation of thrombolytic therapy. The initial area at risk for infarction was visualized on images obtained after the patient had been effectively treated. Imaging performed 5 days later, after repeat injection of [99mTc]isonitrile, showed a smaller myocardial perfusion defect indicating salvage of myocardium. Thus, this technique offers promise as a noninvasive means of assessing the area at risk, the success of reperfusion, and the presence of salvaged myocardium, early in the course of acute myocardial infarction

  8. Retention mechanism of technetium-99m-HM-PAO: intracellular reaction with glutathione

    Preparations of d,l- and meso-hexamethylpropyleneamine oxime (HM-PAO) labeled with technetium-99m were added to rat brain homogenates diluted with phosphate buffer (1:10). The conversion of d,l-HM-PAO to hydrophilic forms took place with an initial rate constant of 0.12 min-1. Incubation of the brain homogenate with 2% diethyl maleate for 5 h decreased the homogenate's measured glutathione (GSH) concentration from 160 to 16 microM and decreased the conversion rate to 0.012 min-1. Buffered aqueous solutions of glutathione rapidly converted the HM-PAO tracers to hydrophilic forms having the same chromatographic characteristics as found in the brain homogenates. The rate constant for the conversion reaction of d,l-HM-PAO in GSH aqueous solution was 208 and 317 L/mol/min in two different assay systems and for meso-HM-PAO the values were 14.7 and 23.2 L/mol/min, respectively. Rat brain has a GSH concentration of about 2.3 mM and the conversion of the d,l-HM-PAO due to GSH alone should proceed with a rate constant of 0.48 to 0.73 min-1 and be correspondingly 14-fold slower for meso-HM-PAO. In human brain, the in vivo data of Lassen et al. show a conversion rate constant of 0.80 min-1. This correspondence of values supports the notion that GSH may be important for the in vivo conversion of 99mTc-labeled HM-PAO to hydrophilic forms and may be the mechanism of trapping in brain and other cells. A kinetic model for the trapping of d,l- and meso-HM-PAO in tissue is developed that is based on data of GSH concentration in various organs

  9. Radio-UHPLC: A tool for rapidly determining the radiochemical purity of technetium-99m radiopharmaceuticals?

    Determining the radiochemical purity (RCP) of technetium-99m (99mTc) radiopharmaceuticals using the method described in the package insert is a time-consuming process, requiring particular attention in order to achieve accurate RCP results. The purpose of this study was to evaluate whether radio-ultra high performance liquid chromatography (radio-UHPLC) may be an alternative method for RCP testing of 99mTc-tetrofosmin, 99mTc-MAG3 and 99mTc-sestamibi. Results obtained using radio-UHPLC were in excellent agreement with the standard method, with total analysis time being reduced to less than 3 min. - Highlights: • Radiochemical purity of 3 technetium-99m radiopharmaceuticals was evaluated using radio-UHPLC. • Results obtained were in agreement with those obtained using the standard method. • Analysis time was less than 3 min using radio-UHPLC. • Radio-UHPLC could be proposed as an alternative technique for radiochemical purity determination

  10. Evaluation of radiolabeling of annexin A5 with technetium-99m: influence of the labeling methods on physico-chemical and biological properties of the compounds; Avaliacao da radiomarcacao da anexina A5 com tecnecio-99m: influencia do metodo de marcacao nas propriedades fisico-quimicas e biologicas do composto

    Santos, Josefina da Silva

    2009-07-01

    Annexin A5 (ANXA5) is an intracellular human protein of 36 kDa with high affinity for membrane-bound phosphatidylserine that is selectively exposed on the surface of cells undergoing apoptosis. Apoptosis is important in normal physiology and innumerous pathologic states. Clinical applications for ANXA5 imaging are being developed in oncology, organ transplantation and cardiovascular diseases. Many strategies to radiolabel the protein have been described, including direct labeling, derivatization through a bifunctional chelating agent (BFC), production of mutated protein or peptide analogs. Several {sup 99}mTc-labeling techniques have been reported using different cores, including [Tc=O]{sup +3}, [Tc]HYNIC, [Tc{identical_to}N]+2 and [Tc(CO{sub 3})]{sup +1}. In this study, we evaluated the influence of {sup 99}mTc cores on biological behavior and physico-chemical properties of radiolabeled annexin. Radiolabeling procedure using [Tc{identical_to}N]{sup +2} core was a two-step procedure including the reaction of {sup 99}mTcO4 - with SDH in the presence of SnCl{sub 2} and PDTA to obtain the intermediate {sup 99}mTcN-SDH, and successive addition of ANXA5. The results obtained were not satisfactory, despite the high efficiency in the production of the intermediate. The [Tc=O]{sup +3} core was produced using the ethylene dicysteine (EC) as BFC. TSTU was employed in the derivatization to produce the corresponding hydroxysuccinimide ester. Different ANXA5:EC ratios were studied and all labeling conditions resulted in high radiochemical yield but with differences in lipophilicity, stability, biological distribution and affinity for apoptotic cells. The HYNIC-ANXA5 also produced the labeled protein with high radiochemical yield. The stability of the radiolabeled ANXA5 was evaluated after storing at room temperature, at 2 - 8 degree C and in human serum at 37 degree C. The analysis of these results showed that the {sup 99}mTc-EC-ANXA5 (ratio 10-2) was the most stable compound

  11. Novel 99mTc labeled σ receptor ligand as a potential tumor imaging agent

    2006-01-01

    A novel 99mTc labeled complex, [N-[2-((2-oxo-2-(4-(3-phenylpropyl)piperazin-1-yl)ethyl) (2-mercaptoethyl)amino)acetyl]-2-aminoethanethiolato]Technetium(V) oxide (PPPE-MAMA′-99mTcO) ([99mTc]-2) has been designed and prepared based on the integrated approach. The corresponding rhenium complex (PPPE-MAMA′-ReO)(Re-2) has been prepared and characterized. In vitro competition binding assays show moderate affinity of Re-2 towards σ1 and σ2 receptors with Ki values of 8.67 ± 0.07 and 5.71 ± 1.88 μmol, respectively. Planar images obtained at 0.5 h, 4 h, 20 h after I.v. Injection indicate the accumulation of [99mTc]-2 in MCF-7 human breast tumor bearing mice at 20 h. Furthermore, the accumulation of [99mTc]-2 has been inhibited at 20 h after co-injection of [99mTc]-2 plus haloperidol (1 mg/kg). Biodistribution studies of [99mTc]-2 display an in vivo tumor uptake of 0.14% ± 0.01% ID/g at 24 h post I.v. Injection with a tumor/muscle ratio of 6.02 ± 0.87. The above results suggest that [99mTc]-2, derived from a previously published lead compound, retains certain tumor uptake and affinity for σ receptors. [99mTc]-2 may be used as a basis for further structural modifications to develop tumor imaging agents with high affinity for σ receptors.

  12. Induction of chromosome aberrations in human lymphocytes by technetium-99m. In vitro and in vivo studies

    In Nuclear Medicine, total body dose calculated after a technetium 99m labeled pharmaceutical administration was very low. Nevertheless, risks evaluation of the radio-induced genetics damages at low doses has become a public health priority. Peripheral lymphocytes can be used to study the effects of ionizing radiations on human cells. The induction by ionizing radiations of unstable structural chromosome aberrations (dicentrics, centrics, and fragments) in peripheral blood lymphocytes is considered to be a useful technique to complete physical dosimetry, and presently is the most advanced biological dosimeter. The aim of the study was to evaluate the potential cytogenetic effects of in vitro and in vivo exposure to technetium 99m (99mTc). Firstly, to evaluate the level of 99mTc activity able to produce a significant number of unstable chromosomal aberrations, specific relationships between activity and number of unstable chromosomal aberrations was established in vitro. The whole blood in vitro irradiation procedure has been performed during 3 hours using microspheres labeled with increasing activities of 99mTc (0, 37, 74, 148, 296, and 444 MBq). Secondly, blood samples from 5 patients scheduled for benign bone disease scintigraphy were collected before and 6 hours after administration of 925 MBq of 99mTc-HDP. Both irradiated whole-blood samples obtained in vitro or in vivo are prepared for conventional scoring by classical Fluorescence Plus Giemsa. For in vivo study, 250 and 500 metaphases were scored respectively before and 6 hours after a bone scan undergone. For in vitro studies, 750 cells were scored per activity. The distribution of unstable chromosome aberrations after in vitro 99mTc irradiation follows a Poisson law. We observed no cytogenetic effect induced by clinical exposure to 99mTc 6 hours after administration versus the control point, as predicted by the in vitro results. Nevertheless, unstable anomalies are lethal to the cell and therefore are

  13. Induction of chromosome aberrations in human lymphocytes by technetium-99m. In vitro and in vivo studies

    Jacquet, N.; Petiet, A.; Colas-Linhart, N. [Universit Paris-7 (France). Faculte de Medecine Xavier Bichat; Guiraud-Vitaux, F.; Leroy, A.; Voisin, P.

    2000-05-01

    In Nuclear Medicine, total body dose calculated after a technetium 99m labeled pharmaceutical administration was very low. Nevertheless, risks evaluation of the radio-induced genetics damages at low doses has become a public health priority. Peripheral lymphocytes can be used to study the effects of ionizing radiations on human cells. The induction by ionizing radiations of unstable structural chromosome aberrations (dicentrics, centrics, and fragments) in peripheral blood lymphocytes is considered to be a useful technique to complete physical dosimetry, and presently is the most advanced biological dosimeter. The aim of the study was to evaluate the potential cytogenetic effects of in vitro and in vivo exposure to technetium 99m (99mTc). Firstly, to evaluate the level of 99mTc activity able to produce a significant number of unstable chromosomal aberrations, specific relationships between activity and number of unstable chromosomal aberrations was established in vitro. The whole blood in vitro irradiation procedure has been performed during 3 hours using microspheres labeled with increasing activities of 99mTc (0, 37, 74, 148, 296, and 444 MBq). Secondly, blood samples from 5 patients scheduled for benign bone disease scintigraphy were collected before and 6 hours after administration of 925 MBq of 99mTc-HDP. Both irradiated whole-blood samples obtained in vitro or in vivo are prepared for conventional scoring by classical Fluorescence Plus Giemsa. For in vivo study, 250 and 500 metaphases were scored respectively before and 6 hours after a bone scan undergone. For in vitro studies, 750 cells were scored per activity. The distribution of unstable chromosome aberrations after in vitro 99mTc irradiation follows a Poisson law. We observed no cytogenetic effect induced by clinical exposure to 99mTc 6 hours after administration versus the control point, as predicted by the in vitro results. Nevertheless, unstable anomalies are lethal to the cell and therefore are

  14. A partial defect in technetium-99m pyrophosphate image suggesting cardiac rupture following acute myocardial infarction

    We present the case of a 70-year-old woman with acute myocardial infarction who died of cardiac rupture on the 2nd hospital day. Dual isotope single photon emission tomography (SPET) using thallium-201 chloride and technetium-99m pyrophosphate (PYP) perforemd on the 2nd hospital day showed a large perfusion defect in the anteroseptal wall on 201Tl image and a increased accumulation on 99mTc-PYP image in the anterior area consistent with a partial defect. Autopsy performed 1 h after death revealed a tear in the left ventricular anterior wall consistent with the defect on the 99mTc-PYP image. We propose that the finding of a partial defect in 99mTc-PYP is an interesting finding which may be associated with cardiac rupture following acute myocardial infarction. (orig.)

  15. Imaging of dopamine transporters in humans with technetium-99m TRODAT-1

    Technetium-99m TRODAT-1, a tropane derivative, has shown promise as a tracer for the imaging of dopamine transporters in preliminary studies in rats and baboons. The present report concerns the first study of the use of [99mTc]TRODAT-1 for the same purpose in humans. The specific uptake of [99mTc]TRODAT-1 in dopamine transporter sites located in the basal ganglia area was confirmed: the best contrast between the basal ganglia and the occipital area, which is devoid of dopamine transporters, was achieved at 120-140 min following injection. The development of a 99mTc-based agent bypasses the need for cyclotron-produced radionuclides, which will be of benefit for routine clinical studies. (orig.). With 2 figs

  16. Abnormal uptake of technetium-99m hexakis-2-methoxyisobutylisonitrile in a primary cardiac lymphoma

    Medolago, G.; Virotta, G.; Bertocchi, C. (Ospedali Riuniti di Bergamo (Italy). Dept. of Nuclear Medicine); Piti, A.; Tespili, M.; D' Adda, F. (Ospedali Riuniti di Bergamo (Italy). Dept. of Cardiology); Rottoli, M.R. (Ospedali Riuniti di Bergamo (Italy). Dept. of Neurology); Comotti, B. (Ospedali Riuniti di Bergamo (Italy). Dept. of Hematology); Motta, T. (Ospedali Riuniti di Bergamo (Italy). Dept. of Pathology); Orlandi, C. (Du Pont Pharma, North Billerica, MA (United States))

    1992-03-01

    Abnormally high uptake of technetium-99m hexakis-2-methoxyisobutylisonitrile ({sup 99m}Tc-SESTAMIBI) in the right ventricle and in the septum was observed in a 47-year-old woman initially presenting with dysarthria and left hemiparesis. Endomyocardial biopsy demonstrated a high-grade malignant non-Hodgkin's lymphoma. Complete remission was achieved by combined cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherpay and radiotherapy of the heart and mediastinum. The post-remission single photon emission tomography (SPET) {sup 99m}Tc-SESTAMIBI study showed a homogeneous distribution pattern, in agreement with echocardiography computed tomography and magnetic resonance imaging. Increased uptake of {sup 99m}Tc-SESTAMIBI, a myocardial perfusion agent, has been observed in some benign and malignant tumours. It may prove to be useful in the diagnosis and follow-up of malignancies. (orig.).

  17. Abnormal uptake of technetium-99m hexakis-2-methoxyisobutylisonitrile in a primary cardiac lymphoma

    Abnormally high uptake of technetium-99m hexakis-2-methoxyisobutylisonitrile (99mTc-SESTAMIBI) in the right ventricle and in the septum was observed in a 47-year-old woman initially presenting with dysarthria and left hemiparesis. Endomyocardial biopsy demonstrated a high-grade malignant non-Hodgkin's lymphoma. Complete remission was achieved by combined cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherpay and radiotherapy of the heart and mediastinum. The post-remission single photon emission tomography (SPET) 99mTc-SESTAMIBI study showed a homogeneous distribution pattern, in agreement with echocardiography computed tomography and magnetic resonance imaging. Increased uptake of 99mTc-SESTAMIBI, a myocardial perfusion agent, has been observed in some benign and malignant tumours. It may prove to be useful in the diagnosis and follow-up of malignancies. (orig.)

  18. Effects of concurrent drug therapy on technetium /sup 99m/Tc gluceptate biodistribution

    Hinkle, G.H.; Basmadjian, G.P.; Peek, C.; Barker, K.K.; Ice, R.D.

    1982-11-01

    Drug interactions with /sup 99m/Tc gluceptate resulting in altered biodistribution were studied using chart review and animal tests. Charts of nine patients who had abnormal gallbladder uptake of technetium /sup 99m/Tc gluceptate during a two-year period were reviewed to obtain data such as concurrent drug therapy, primary diagnosis, and laboratory values. Adult New Zealand white rabbits were then used for testing the biodistribution of technetium /sup 99m/Tc gluceptate when administered concurrently with possibly interacting drugs identified in the chart review--penicillamine, penicillin G potassium, penicillin V potassium, acetaminophen, and trimethoprim-sulfamethoxazole. Chart review revealed no conclusive patterns of altered biodistribution associated with other factors. The data did suggest the possibility that the five drugs listed above might cause increased hepatobiliary clearance of the radiopharmaceutical. Animal tests showed that i.v. penicillamine caused substantial distribution of radioactivity into the gallbladder and small bowel. Minimally increased gallbladder radioactivity occurred when oral acetaminophen and trimethoprim-sulfamethoxazole were administered concurrently. Oral and i.v. penicillins did not increase gallbladder activity. Penicillamine may cause substantial alteration of the biodistribution of technetium /sup 99m/Tc gluceptate.

  19. Assessment of the effect of Bacopa monnieri (L. Wettst. extract on the labeling of blood elements with technetium-99m and on the morphology of red blood cells Avaliação do efeito do extrato de Bacopa monnieri (L. Wettst. na marcação de elementos sanguíneos com tecnécio-99m e na morfologia de células vermelhas do sangue

    Kakali De

    2009-09-01

    Full Text Available Bacopa monnieri (L. Wettst. (BM, a traditional Ayurvedic medicine, used for centuries as a memory enhancing, anti-inflammatory, antipyretic, sedative and antiepileptic agent. BM extract have been extensively investigated by several authors for their neuropharmacological effects. In nuclear medicine, red blood cells (RBC labeled with technetium-99m (99mTc have several clinical applications. However, data have demonstrated that synthetic or natural drugs could modify the labeling of RBC with 99mTc. As Bacopa monnieri is extensively used in medicine, we evaluated its influence on the labeling of RBC and plasma proteins using technetium-99m (99mTc. This labeling procedure depends on a reducing agent and usually stannous chloride is used. Blood was incubated with BM extracts. Stannous chloride solution and 99mTc were added. Blood was centrifuged and plasma (P and blood cells (BC were isolated. Samples of P or BC were also precipitated, centrifuged and insoluble fraction (IF and soluble fraction (SF were separated. The percentage of radioactivity (%ATI in BC, IF-BC and IF-P were calculated. The %ATI significantly decreased on BC from 95.53±0.45 to 35.41±0.44, on IF-P from 80.20±1.16 to 7.40±0.69 and on IF-BC from 73.31±1.76 to 21.26±1.40. The morphology study of RBC revealed important morphological alterations due to treatment with BM extracts. We suggest that the BM extract effect could be explained by an inhibition of the stannous and pertechnetate ions or oxidation of the stannous ion or by damages induced in the plasma membrane.Bacopa monnieri (L. Wettst. (BM, uma planta tradicional da medicina ayurvédica, é usada por séculos para problemas de memória, antiinflamatória, antitérmica, sedativa e como agente anti-epiléptico. O extrato BM têm sido extensivamente investigada por diversos autores por seus efeitos neurofarmacológicas. Na medicina nuclear, os glóbulos vermelhos (RBC marcados com tecnécio-99m (99mTc tem várias aplica

  20. Effect of graded hypoxia on retention of technetium-99m-nitroheterocycle in perfused rat heart

    The purpose of this investigation was to determine the effects of graded hypoxia on the retention of a 99mTc-labeled nitroimidazole. Rat hearts were perfused retrogradely with Krebs-Henseleit buffer at 37 degrees C and paced at 5 Hz. After a 20-min stabilization period, coronary flow was maintained at 8 ml/min/g wet wt and the hearts were perfused with media equilibrated with gas mixtures containing 5% CO2 and various levels of O2, from 544 to 29 Torr. Technetium-99m-O(PnAO-1-(2-nitroimidazole)), BMS-181321, was infused for 20 min into a side port of the aortic cannula. Perfusion continued for an additional 40 min to allow for compound clearance. Each decrease of perfusate PO2 brought about an increase in the retention of BMS-181321, resulting in a good correlation between its retention and perfusate PO2 (r=0.97). Myocardial oxygen consumption was independent of oxygen delivery when the perfusate oxygen pressure was greater than 350 Torr. Below this value, oxygen consumption declined markedly as influent PO2. A good correlation was obtained between retention of the nitroheterocycle and the cytosolic lactate/pyruvate ratio (r=0.98). When glucose was omitted from the perfusate (PO2=27 Torr), retention of the nitroheterocycle was increased by about 25% as compared to hearts perfused in the presence of this substrate. These results indicate that myocardial retention of BMS-181321 is coupled to the level of tissue oxygenation and that hypoxic retention may be affected by substrate input. 24 refs., 3 figs., 1 tab

  1. Biological effects of technetium-99 m and technetium 99 in Escherichia Coli and Salmonella typhimurium cultures

    The biological effects of the 99m Tc of the 99m Tc and 99 Tc and 99m Tc and 99 Tc on Escherichia coli (K12S, BW 9091 and AB 2463) and Salmonella typhimurium (TA 97, TA 98, TA 100 and TA 102) cultures are studied. The suggest that: Auger and or internal conversion electrons are very relevant to the 99m Tc induced inactivation effects, the pre-treatment with metal ion chelator or Sn Cl2 confers cells protection against the lethal effects of 99m Tc and the 99 Tc is a weak genotoxic and it is not mutagenic agent. (author). 25 refs, 3 figs, 3 tabs

  2. Radiolabeling of gemifloxacin with technetium-99m and biological evaluation in artificially Streptococcus pneumoniae infected rats

    In the current investigation complexation of the gemifloxacin (GIN) with technetium-99 m (99mTc) and its biological evaluation in artificially Streptococcus pneumoniae (S. pneumoniae) infected rats was assessed as potential S. pneumoniae infection radiotracer. Radiochemically the 99mTc-GIN complex was further analyzed in terms of stability in saline, in vitro stability in serum at 37 deg C, in vitro binding with S. pneumoniae and biodistribution in artificially S. pneumoniae (living and heat killed) infected rats. The complex was found 97.25 ± 0.25% radiochemically stable in saline at 30 min after reconstitution. The stability of the 99mTc-GIN complex was decreased to 90.50 ± 0.20% within 240 min after reconstitution. In serum the 99mTc-GIN complex showed stable profile with the appearance of 18.85% free tracer within 16 h of incubation. The 99mTc-GIN complex showed saturated in vitro binding with S. pneumoniae after different intervals. Almost five fold uptake was observed in living S. pneumoniae infected muscle of the rats as compared to the inflamed and normal muscle. No significant difference in the uptake of heat killed S. pneumoniae infected, inflamed and normal muscles of the rats. The high RCP yield in saline, in vitro permanence in serum, in vitro binding with living S. pneumoniae and biodistribution in artificially S. pneumoniae infected rats we recommend the 99mTc-GIN as potential S. pneumoniae infection radiotracer. (author)

  3. An investigation into the technical feasibility of cyclotron production of technetium-99m

    The role of technetium-99m in nuclear medicine is well established with 80 per cent to 90 per cent of all nuclear medicine studies utilising this isotope. Technetium-99m is currently produced from nuclear reactors via production of the parent radionuclide molybdenum-99. The reactor production of 99mTc has both significant financial and environmental costs, with unresolved problems in the areas of radioactive waste disposal and reactor decommissioning. Recent scientific publications have indicated that medical quality 99mTc may be produced using cyclotrons without having the associated problems of waste disposal and decommissioning. Further scientific research is now required to demonstrate the feasibility of this cyclotron production technique. A collaboration between the Cyclotron and PET Centre, Austin Hospital, the National Medical Cyclotron, ANSTO, Sydney, and the Crocker Nuclear Laboratory, University of California, Davis, USA has been proposed. The general objective of the proposed collaboration is to acquire additional scientific data to evaluate the 99mTc cyclotron production method and to determine the feasibility of cyclotron technology for Australian nuclear medicine. 16 refs., 2 tabs

  4. Extraction-chromatographic generator of technetium-99m. Principles of functioning and exploiting conditions

    Technetium-99m pharmaceuticals are spin-off products resulting from the decomposition of the 99Mo radioactive nuclide; they occupy leading positions in world medical diagnostics. Technetium-99m is β -relay product of radioactive nuclide of molybdenum-99. For dividing of genetically connected pair of 99Mo / 99mTc is using generators sets, in which accumulation of technetium-99m lasts for period of 22 hours. 99mTc generators could be subdivided for 3 basic types: chromatographic (sorbtioned), sublimated and extractioned ones. Extraction technology is concentrated, and it lets to receive solutions with high specific activity even from low level activity molybdenum-99, which is produced by reaction of radioactive capture 98Mo (n,γ ) 99Mo form natural molybdenum targets. Main defects of extracted generators: big size of extractors; necessity to control over procedure of separation extracting substance from water phase with the idea to decrease its wastes with visual or other method; long-time period to proceed preparation (1,5 - 2 hours), mainly because of extracting substance evaporation period; high requirements to personnel. Pointed defects prevent to use extracted generators directly in medical radiological laboratories. NPI at TPU developed an extraction-chromatographic generator with the mobile compact extraction device, based on the 'black box' principle. Its construction ensures self-regulation of phase division level. Total volume of extraction substance is not more then 80 cm3 with 110 mm high. It can be transported in safe box without unpacking directly in medical establishments. Frequent extraction with the same low volume of extracting substance provides high level of yield of technetium-99m. Subdividing of radioactive nuclide is going at chromatographic column with Al2O3 sorbent. Extraction-chromatographic generator at the same time then technetium-99m products became lower price let's to solve problem to provide regional clinics, there are middle

  5. Extraction-chromatographic generator of technetium-99m. Principle of functioning and exploiting conditions

    Full text: Technetium-99m pharmaceuticals are spin-off products resulting from the decomposition of the 99Mo radioactive nuclide; they occupy leading positions in world medical diagnostics. Technetium-99m is β -relay product of radioactive nuclide of molybdenum-99. For dividing of genetically connected pair of 99Mo / 99mTc is using generators sets, in which accumulation of technetium-99m lasts for period of 22 hours. 99m Tc generators could be subdivided for 3 basic types: chromatographic (sorbtioned), sublimated and extractioned ones. Extraction technology is concentrated, and it lets to receive solutions with high specific activity even from low level activity molybdenum-99, which is produced by reaction of radioactive capture 98Mo (n,γ ) 99Mo form natural molybdenum targets. Main defects of extracted generators: big size of extractors; necessity to control over procedure of separation extracting substance from water phase with the idea to decrease its wastes with visual or other method; long-time period to proceed preparation (1,5 - 2 hours), mainly because of extracting substance evaporation period; high requirements to personnel. Pointed defects prevent to use extracted generators directly in medical radiological laboratories. NPI at TPU developed an extraction-chromatographic generator with the mobile compact extraction device, based on the 'black box' principle. Its construction ensures self-regulation of phase division level. Total volume of extraction substance is not more then 80 cm3 with 110 mm high. It can be transported in safe box without unpacking directly in medical establishments. Frequent extraction with the same low volume of extracting substance provides high level of yield of technetium-99m. Subdividing of radioactive nuclide is going at chromatographic column with Al2O3 sorbent. Extraction-chromatographic generator at the same time then technetium-99m products became lower price let's to solve problem to provide regional clinics, there are

  6. Technetium-99m-N,N-ethylenedicysteine and Tc-99m DMSA scintigraphy in the evaluation of renal parenchymal abnormalities in children

    Technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) as a static renal agent is currently the most frequently used agent in the detection of renal scarring, and allows accurate calculation of differential renal function (DRF). But this agent has some disadvantages such as relatively higher radiation dose and time consumption. The purpose of this study was to evaluate the potential of summed image that obtained from parenchymal phase of the dynamic technetium-99m-N,N-ethylenedicysteine (Tc-99m EC) scintigraphy in the detection of renal parenchymal defects and in the estimation of DRF, and to compare the results of this method with those of Tc-99m DMSA scintigraphy. The uptake ratios of the kidney to body background were also calculated for these two methods. Twenty-nine children with various renal disorders underwent both static Tc-99m DMSA and dynamic Tc-99m EC scintigraphy. The cortical analysis of Tc-99m EC scintigraphy was performed on the summed image obtained from dynamic images using the time interval between the first 45-120 sec. There was a very close correlation between these two methods with respect to DRF (r=0.99). In the detection of renal parenchymal lesions, scintigraphy with Tc-99m DMSA detected more lesions, and the sensitivity and specificity of the summed Tc-99m EC images were calculated as 92.6% and 100%, respectively. In addition, the ratios of mean uptake values for Tc-99m DMSA and Tc-99m EC images were 7.59±2.17 and 2.95±0.91, respectively. This ratio of Tc-99m EC seems to be acceptable and allows good delineation of the kidneys. But, the main disadvantages of the summed Tc-99m EC images in comparison with static Tc-99m DMSA images are the use of only posterior projection that may be an important drawback in patients with abnormal kidney positions, lower image counts and higher pixel size because of dynamic acquisition. These results show that summed Tc-99m EC images with an acceptable high image contrast provide an accurate DRF calculation

  7. Preparation and biological evaluation of technetium-99m-phenylethylamine complexes

    Vitale, A.A.; Stahl, A.E.; Pomilio, A.B. [Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales; Calvino, M.A.; Ferrari, C.C. [Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales]|[INEUCI-CONICET, FCEN, UBA (Argentina)

    1995-06-01

    Biological and chemical characteristics of {sup 99m}Tc-phenethylamines complexes are presented. 2-(4,5-Dimethoxy-2-nitrophenyl)ethylamine, 2-(3, 4-dimethoxyphenyl)ethylamine and 2-(2-amino-4,5-dimethoxyphenyl)-ethylamine were used as ligands. A preliminary evaluation of these {sup 99m}Tc-complexes as dopamine receptor radioligands was also performed. Net charges at each atom were also calculated by a semiempirical ZINDO/1 method for comparison of free ligands parameters with those of the respective technetium-complexes. (Author).

  8. Biodistribution of technetium-99m pertechnetate after total colectomy in rats

    Meneses Rego, Amalia Cinthia; Alcantara Oliveira Ramalho, Rachel; Tabosa Egito, Eryvaldo Socrates; Araujo-Filho, Irami; Medeiros Azevedo, Italo [Postgraduate Program in Health Sciences, Federal University of Rio Grande do Norte (UFRN), Ave. Miguel Alcides Araujo 1889, Natal-RN 59078-270 (Brazil); Palestro, Christopher J. [Division of Nuclear Medicine and Molecular Imaging, North Shore Long Island Jewish Health System, Manhasset and New Hyde Park, NY (United States); Medeiros, Aldo Cunha, E-mail: aldom@uol.com.b [Postgraduate Program in Health Sciences, Federal University of Rio Grande do Norte (UFRN), Ave. Miguel Alcides Araujo 1889, Natal-RN 59078-270 (Brazil)

    2010-12-15

    This study evaluated the effects of total colectomy on the biodistribution of technetium-99m pertechnetate ({sup 99m}TcO{sub 4}{sup -}) on the 28th postoperative day in rats. Samples of several organs were harvested for counting the percent of injected radioactivity/g of tissue (%ATI/g). The %ATI/g in colectomy rats was higher in the stomach and ileum than in sham and controls (p<0.05). Increase in mucosa and muscularis size of ileum was observed. Colectomy was associated with lower biodistribution in bladder and thyroid, T3, and T4, than in controls.

  9. Structural Investigation of Technetium-Diphosphonate Complex 99mTc-MDP

    Ling Qiu; Jian-guo Lin; Xue-hai Ju; Xue-dong Gong; Shi-neng Luo

    2011-01-01

    Density functional theory method has been employed to investigate the structures of the prototypical technetium-labeled diphosphonate complex 99mTc-MDP, where MDP represents methylenediphosphonic acid. A total of 14 trial structures were generated by allowing for the geometric, conformational, charge, and spin isomerism. Based on the optimized structures and calculated energies at the B3LYP/LANL2DZ level, two stable isomers were determined for the title complex. And they were further studied systematically in comparison with the experimental structure. The basis sets 6-31G*(LANL2DZ for Tc), 6-31G*(cc-pVDZ-pp for Tc), and DGDZVP have also been employed in combination with the B3LYP functional to study the basis set effect on the geometries of isomers. The optimized structures agree well with the available experimental data, and the bond lengths are more sensitive to the basis set than the bond angles. The charge distributions were studied by the Mulliken population analysis and natural bond orbital analysis. The results reflect a significant ligand-to-metal electron donation.

  10. Labelling malaria-infected human erythrocytes with Tc-99m

    Aim: Malaria is an old and a very common disease, especially in undeveloped countries. The malaria parasites infect the erythrocytes and the aim of this work was to label infected cells for future studies of their distribution and life span. Material and Method: With a commercial kit containing stannous fluoride and sodium medronate, which is used to label erythrocytes in vivo, in vitro and in vivo/vitro methods, we labelled the cells by using a modified method and a small volume, 5 - 50 microlitre, of packed cells. The cells were labelled with Tc-99m in the range of 60 - 1500 MBq. The kit was reconstituted with saline and the pH was adjusted to 7.0. The cells were incubated with 1 ml of the kitsolution in 370C for 5 min. The remaining Sn-ions were reduced by adding NaOCl and then the solution was centrifuged.The supernantant was discarded and the Tc-99m was added to the precipitate and incubated 370C for 20 min and then washed 3 times. This labelling procedure was performed on both infected and on non-infected cells. Results: Ten samples of cells have been labelled. The best labelling result was obtained using 7 - 20 MBq per 10 microlitre of packed cells. The labelling efficiency was, on average, 35%. Conclusion: It is possible to label both infected and non-infected cells in very small volumes. The cells were visually inspected in a microscope and were viable after labelling. Furthermore, the cell distribution was traced in vivo in an animal model by a gamma camera

  11. Technetium-99m labeled 1-(4-fluorobenzyl)-4-(2-mercapto-2-methyl-4-azapentyl)-4- (2-mercapto-2-methylp ropylamino)-piperidine and iodine-123 metaiodobenzylguanidine for studying cardiac adrenergic function: a comparison of the uptake characteristics in vascular smooth muscle cells and neonatal cardiac myocytes, and an investigation in rats

    Samnick, Samuel E-mail: rassam@uniklinik-saarland.de; Scheuer, Claudia; Muenks, Sven; El-Gibaly, Amr M.; Menger, Michael D.; Kirsch, Carl-Martin

    2004-05-01

    In developing technetium-99m-based radioligands for in vivo studies of cardiac adrenergic neurons, we compared the uptake characteristics of the {sup 99m}Tc-labeled 1-(4-fluorobenzyl)-4-(2-mercapto-2-methyl-4-azapentyl)-4- (2-mercapto-2-methylpropylamino)-piperidine ({sup 99m}Tc-FBPBAT) with those of the clinically established meta-[{sup 123}I]iodobenzylguanidine ({sup 123}I-MIBG) in rat vascular smooth muscle cells and neonatal cardiac myocytes. Furthermore, the cardiac and extracardiac uptake of both radiopharmaceuticals was assessed in intact rats and in rats pretreated with various {alpha}- and {beta}-adrenoceptor drugs, and adrenergic reuptake blocking agents. The uptake of {sup 99m}Tc-FBPBAT and {sup 123}I-MIBG into vascular smooth muscle cells and neonatal cardiac myocytes was rapid; more than 85% of the radioactivity accumulation into the cells occurring within the first 3 minutes. Radioactivity uptake after a 60-minute incubation at 37 degree sign C (pH 7.4) varied from 15% to 65% of the total loaded activity per million cells. In all cases, {sup 99m}Tc-FBPBAT showed the higher uptake, relative to {sup 123}I-MIBG, at any given cell concentration. The cellular uptake of {sup 99m}Tc-FBPBAT was lower at 4 degree sign C and 20 degree sign C than at 37 degree sign C. In contrast, the {sup 123}I-MIBG uptake was only slightly temperature dependent. Inhibition experiments confirmed that the cellular uptake of {sup 123}I-MIBG is mediated by the uptake-I carrier, whereas {alpha}{sub 1}- and {beta}{sub 1}-adrenoceptors were predominantly involved in the uptake of {sup 99m}Tc-FBPBAT into the cardiovascular tissues. Biodistribution studies in rats showed that {sup 99m}Tc-FBPBAT accumulated in myocardium after intravenous injection. Radioactivity in rat heart amounted to 2.32% and 1.91% of the injected dose per gram at 15 and 60 minutes postinjection, compared with 3.10% and 2.21% injected dose per gram of tissue (%ID/g) in the experiment with {sup 123}I

  12. Anomalies in hepatobiliary excretion of Technetium-99m-MAG3 preparations

    Technetium-99m-MAG3 is accepted as a renal tubular function agent. However, sporadic liver and gall bladder visualisation during its clinical use is clearly a disadvantage. HPLC-purified 99mTc-MAG3 samples exhibited appreciable hepatobiliary uptake (7%), and an elevated level of such uptake was observed in unpurified kit preparations, which was stated to be associated with the excretory property of the radiolabeled kit impurities. To verify this we attempted to quantitate the hepatobiliary uptake of the kit preparations with that of its radiolabeled components. The contribution of each component toward hepatobiliary uptake of the sample was calculated from their abundance in the chelate mixture and the individual biodistribution of the isolated components. However, the anticipated hepatobiliary uptake of different preparations of 99mTc-MAG3 calculated in this way was always lower than that of the experimental value determined directly. Further work is needed to explain the anomaly

  13. Development of methods of labeling pentavalent DMSA with 99mTc and 188Re

    Technetium-99 m is the most useful radionuclide in diagnostic imaging procedures in Nuclear Medicine, more than 80 percent of radiopharmaceuticals are 99mTc-labeled compounds. 99mTc-DMSA(V) has been used for imaging of soft tissue, head and neck tumors. It shows a particularly high specificity for medullary thyroid carcinoma and bone metastases in a variety of cancers. Biodistribution studies of 188Re-DMSA(V) have shown that its general pharmacokinetic properties are similar to that of 99mTc-DMSA(V), so this agent could be used for targeted radiotherapy of these tumors. The aim of this work is the development of methods of labeling DMSA(V) with 99mTc and 188Re. 99mTc-DMSA(V) can be prepared by two methods. One of them is the indirect one, through the use of a commercial kit of DMSA (III), by adjusting the pH from 2.5 to ∼ 8.5 with NaHCO3. This method was evaluated and optimized presenting high labeling yields. The other method is the direct one, through the preparation of a lyophilised kit ready for labeling with 99mTc, being the method of interest of this work, due to the easy of its clinical use. The most adequate formulation of the kit was: 1.71 mg of DMSA, 0.53 mg of SnCl2.2H2O and 0.83 mg of ascorbic acid (pH 9). Labeling yields higher than 95% were achieved labeling this kit with 1 to 2 m L of 99mTc with activities up to 4736 MBq (128 mCi). The kit was stable up to 6 months and biodistribution studies confirmed the quality of the DMSA (V) labeled with 99mTc using this kit. The reduction potential of Re is lower than the one for Tc, so the labeling conditions of 188Re-DMSA(V) are different from the ones used for 99mTc- DMSA(V). 188Re-DMSA(V) is prepared in acid solution, that makes it possible to use the DMSA (III) commercial kit developed for labeling with 99mTc, prepared in pH 2.5, for labeling with 188Re. Labeling yields higher than 95% were achieved with this methodology, with a rection time of 30 minutes at 100 deg C using no more than 1 m L of 188ReO4

  14. The substitution of iodine 131 by Technetium 99m in the application of radiotracers in the sugar cane industry

    A study of the behaviour of Technetium 99m is performed to know if it is possible its use as radiotracer in the evaluation of massecuite crystalizer C or of third. After positive results, it was done a comparative study of the measured doses provoked by the use of iodine 131 and of Technetium 99m on this sugar cane installation. We reached the conclusion that technetium 99m is an obliged substitute of Iodine 131 because it is a radiotracer with better radiologic characteristics to be used on the food-production industry, for example in the sugar cane industry

  15. Somatostatin analogues labelled with 99mTc

    Biological and radiochemical studies have been carried out on two labelled somatostatin analogues, the peptide RC-150 and the Tyr3-Octreotide. Both analogues have been labelled with 99mTc using the direct and the indirect method and MAG-3 and HYNIC as chelating agents. By the direct method RC-150 was labelled using sodium ascorbate and dithionite as reducing agents. The radiochemical purity was 70%. By the indirect method, in the case of RC-160 with MAG-3 a radiochemical purity higher than 70% was attained while a purity of 100% was reached in the case of Tyr3-Octreotide with HYNIC. The biological distribution of HYNIC-Tyr3-Octreotide has been studied in rats. (author)

  16. Clearance of technetium-99m-DTPA and HRCT findings in the evaluation of patients with Idiopathic Pulmonary Fibrosis

    Karkavitsas Nikolaos

    2006-02-01

    Full Text Available Abstract Background Clearance of inhaled technetium-labeled diethylenetriamine pentaacetate (99mTc-DTPA is a marker of epithelial damage and an index of lung epithelial permeability. The aim of this study was to investigate the role of 99mTc-DTPA scan in patients with Idiopathic Pulmonary Fibrosis (IPF. Our hypothesis is that the rate of pulmonary 99mTc-DTPA clearance could be associated with extent of High Resolution Computed Tomography (HRCT abnormalities, cell differential of bronchoalveolar lavage fluid (BALF and pulmonary function tests (PFTs in patients with IPF. Methods We studied prospectively 18 patients (14 male, 4 female of median age 67yr (range 55–81 with histologically proven IPF. HRCT scoring included the mean values of extent of disease. Mean values of these percentages represented the Total Interstitial Disease Score (TID. DTPA clearance was analyzed according to a dynamic study using a Venticis II radioaerosol delivery system. Results The mean (SD TID score was 36 ± 12%, 3 patients had mild, 11 moderate and 4 severe TID. Abnormal DTPA clearance half-time (t1/2 Conclusion Our data suggest that 99mTc-DTPA lung scan is not well associated with HRCT abnormalities, PFTs, and BALF cellularity in patients with IPF. Further studies in large scale of patients are needed to define the role of this technique in pulmonary fibrosis.

  17. Clinical evaluation of technetium-99m infecton for the localisation of bacterial infection

    The aim of the study was to distinguish infection from inflammation in patients with suspected infection using technetium-99m Infecton. Ninety-nine patients (102 studies) referred for infection evaluation underwent imaging with 400 MBq 99mTc-Infecton at 1 and 4 h. Most patients had appropriate microbiological tests and about half (56) had radiolabelled white cell scans as well. No adverse effects were noted in any patient. The clinical efficacy of 99mTc-Infecton depended in part on whether imaging was undertaken during antibiotic therapy for infection or not. In consultation with the microbiologist, 5-14 days of appropriate and successful antibiotic therapy was considered adequate to classify some results as true-negatives. The figures for sensitivity and specificity of 99mTc-Infecton for active or unsuccessfully treated infection were 83% and 91% respectively. It is concluded that 99mTc-Infecton imaging contributed to the differential diagnosis of inflammation. It is being used as the first imaging modality when bacterial infection is suspected. (orig.). With 2 figs., 1 tab

  18. Production and Quality Control of Technetium-99m Radiolabeled Monoclonal Antibody

    M.H. Babaei, Ph.D.

    2007-01-01

    Full Text Available AbstractBackground and purpose: Binding a monoclonal antibody to tumor associated antigens is an effective method for cancer therapy because these agents can specifically target malignant cells. In fact, monoclonal antibodies are effective agents for diagnosis, grading and treatment of different kinds of cancers. In this research, a new monoclonal antibody against colon cancer cells was prepared and radiolabeling with technetium-99m evaluated.Materials and Methods: This research was done in three parts: preparation of hybridoma cell against colon cancer cell line (HT29, production of monoclonal antibody, determination of its characterizations and radiolabeling with technetium-99m.Results: mAb-D2 is an IgG1 with affinity constant of 7.2 × 109M-1 which can recognize CEA in tumor cells. Radiolabeling showed that 99mTc-HYNIC-mAb-D2 complex is stable, immunoradioactive, and has a desirable biodistribution.Conclusion: In this study, we gained a new radiopharmaceutical that may be a good candidate for radioimmunoscintigraphy.

  19. Tc 99m - scorpion venom: labelling, biodistribution and scintiimaging

    Labelling of scorpion (Mesobuthus tamulus concanesis Pocock) venom was successfully achieved with Tc 99m using direct tin reduction procedure. Biodistribution studies were carried out in Wistar rats at different time intervals after i.v. administration of the labelled venom. Scintiimages were obtained after scorpion envenoming using a large field of view gamma camera to ascertain the pharmacological action of venom in the body. Within 5 min of administration, labelled venom was found in the blood (27.7%), muscle (30.11%), bone (13.3%), kidneys (11.5%), liver (10.4%) and other organs. The level of venom in the kidneys was higher than in the liver. The labelled venom was excreted through renal and hepatobiliary pathways. An immunoreactivity study was carried out in rabbits after i.v. injection of labelled scorpion venom followed by the injection of the species specific antivenom. A threefold increase in uptake by the kidneys ss was observed compared with that seen with scorpion venom alone. the neutralisation of the venom in the kidneys was higher than in the liver. (author)

  20. Tc 99m - scorpion venom: labelling, biodistribution and scintiimaging

    Murugesan, S.; Noronha, O.P.D.; Samuel, A.M. [Bhabha Atomic Research Centre, Mumbai (India). Tata Hospital Annexe. Radiation Medicine Center; Murthy, K. Radha Krishna [Seth G.S. Medical College, Mumbai (India). Dept. of Physiology

    1999-07-01

    Labelling of scorpion (Mesobuthus tamulus concanesis Pocock) venom was successfully achieved with Tc 99m using direct tin reduction procedure. Biodistribution studies were carried out in Wistar rats at different time intervals after i.v. administration of the labelled venom. Scintiimages were obtained after scorpion envenoming using a large field of view gamma camera to ascertain the pharmacological action of venom in the body. Within 5 min of administration, labelled venom was found in the blood (27.7%), muscle (30.11%), bone (13.3%), kidneys (11.5%), liver (10.4%) and other organs. The level of venom in the kidneys was higher than in the liver. The labelled venom was excreted through renal and hepatobiliary pathways. An immunoreactivity study was carried out in rabbits after i.v. injection of labelled scorpion venom followed by the injection of the species specific antivenom. A threefold increase in uptake by the kidneys ss was observed compared with that seen with scorpion venom alone. the neutralisation of the venom in the kidneys was higher than in the liver. (author)

  1. Phantom evaluation of simultaneous thallium-201/technetium-99m acquisition in single-photon emission tomography

    This study investigated downscatter effects in cardiac single-photon emission tomographic studies with simultaneous thallium-201/technetium-99m acquisition, and evaluated a previously proposed subtraction technique for downscatter compensation. Ten studies were carried out with different defect sizes and locations and varying activity distributions using four energy windows: 70±10% keV, 140±10% keV, 100±10% KeV, and 103±16% keV. The subtraction technique used the 100- or 103-keV data to remove scattered 99mTc counts from the 70-keV data. The size and contrast of infarcts in the dual-isotope 70-keV image were artificially decreased compared to those in the 140-keV image, caused by scattered 99mTc counts that were comparable to the primary 201Tl counts in the 70-keV window. The subtraction technique produced larger defects and more heterogeneous activity in the myocardial wall in dual-isotope 70-keV images compared to the corresponding 201Tl-only images. These artifacts were caused by the markedly different spatial distributions of scattered 99mTc counts in the 100-keV (or 103-keV) window as compared with the 70-keV window. It is concluded that scattered 99mTc photons may cause overestimation of ischemia and myocardial viability in simultaneous dual-isotope patient studies. The proposed subtraction technique was inaccurate and produced image artifacts. Adequate downscatter compensation methods must be developed before applying simultaneous 201Tl/99mTc acquisition in clinical practice. (orig.). With 6 figs., 3 tabs

  2. Technetium-99m-human polyclonal IgG radiolabeled via the hydrazino nicotinamide derivative for imaging focal sites of infection in rats

    The biologic behavior of human polyclonal immunoglobulin (IgG) radiolabeled with technetium-99m (99mTc) by a novel method, via a nicotinyl hydrazine derivative, was evaluated in rats. Technetium-99m- and indium-111-IgG were co-administered to normal rats and biodistribution was determined at 2, 6, and 16 hr. The inflammation imaging properties of the two reagents were compared in rats with deep-thigh infection due to Escherichia coli. Blood clearance of both antibody preparations was well described by a bi-exponential function: (99mTc-IgG: t1/2 = 3.82 +/- 0.89 and 57.52 +/- 1.70 hr. 111In-IgG: 3.93 +/- 0.117 and 40.71 +/- 1.26 hr). Biodistributions in the solid organs were similar, however, small but statistically significant differences were detected: 99mTc-IgG greater than 111In-IgG in lung, liver, and spleen; 99mTc-IgG less than 111In-IgG in kidney and skeletal muscle (p less than 0.01). At all three imaging times, target-to-background ratio and percent residual activity for the two compounds were remarkably similar. These studies establish that human polyclonal IgG labeled with 99mTc via a nicotinyl hydrazine modified intermediate is equivalent to 111In-IgG for imaging focal sites of infection in experimental animals

  3. Evaluation of the stablilisation of Technetium-99m exametazime utilising cobalt chloride: preliminary results

    A limited post-reconstitution shelf-life of 30 min for Technetium-99m exametazime (Ceretec(R)) restricts its clinical availability. Several attempts have been made to extend the 30 min shelf-life with varying success and a review of published methods concludes that although stabilisation is possible, careful analysis of the radiochemical purity is necessary before use. A method for stabilising 99mTc-exametazime using chloride was investigated. Preparation of the 99mTc-exametazime was as per manufacturer's instructions and cobalt chloride hexahydrate (Aldrich) was used to prepare a 100 μg/mL (0.42 mM) solution. Vials were reconstituted with eluate containing approximately 2 GBq of 99mTc diluted to 5 mL with normal saline. A stabilised 99mTc-exametazime solution was prepared by adding 2mL (200 μg) of the CoCI2.6H2O solution to the Ceretec vial, 2 min post-reconstitution of the 99mTc-exametazime. Analyses of the 99mTc-exametazime solutions were performed at various time points up to six hours post-reconstitution, and the methods used were instant thin layer chromatography (ITLC) and high-performance liquid chromatography (HPLC). Stability of the stabilised 99mTc-exametazime solution was studied in the original manufacturer's glass vial and in disposable syringes. Using the radiochemical purity specification of not less than 80 per cent lipophilic complex, the results indicate that the stabilised radiopharmaceutical which was stable for at least six hours in the original glass vial (n=6), was stable for only two to four hours in a lubricated syringe (Terumo) (n=3) but stable for six hours in an non-lubricated syringe (Discardit II, BD) (n=3). This preliminary investigation indicates that 99mTc-exametazime stabilised with cobalt chloride hexahydrate appears to be stable for at least six hours in both the original vial and non-lubricated syringes

  4. Determination of complex forming conditions of 8-hydroxyquinoline with technetium-99m

    Complex forming conditions of 8-hydroxyquinoline with 99mTc have been specified. 99mTcO4- has been reduced by SnCl2 to a lower oxidation level. Labeling yields have been determined by ITLC (Instant Thin Layer Chromatography). Various parameters, such as pH, temperature, reaction time, ligand to SnCl2 ratio, which can affect the labeling yields, have been determined. Optimum conditions are 4-7 for pH; 15-20 deg C (room) for temperature, 1.55 for ligand to SnCl2 ratio and 5 min for reaction time. (author). 10 refs., 3 figs., 1 tab

  5. Active and passive vectorization of technetium99m and 188rhenium radiopharmaceuticals for medical imaging and radiotherapy

    Research for new molecules for nuclear medicine is a field in constant development. Over the past few years, development of new radiopharmaceuticals for radiotherapy has renewed interest for rhenium chemistry. Indeed, its two isotopes 186Re and 188Re, owing to their ideal properties and their similitude with 99mTc, which is widely used as a radiotracer for diagnostic imaging, seem very promising for the preparation of radiopharmaceuticals. In the first part of this manuscript, the synthesis of rhenium and technetium-99 complexes, [M(RPhCS3)2(RPhCS2)] (M = Re, Tc), is described. The preparation of technetium99m based radiopharmaceuticals, analogues to the pondered complexes, is also described. The stability/reactivity of these complexes has been studied by exchange reactions with potential ligands, specially dithiocarbamates, and also by UV-visible absorption spectroscopy and thermogravimetry. The reactivity of the complexes towards dithiocarbamates leads to the possibility to bind biomolecules to the metallic core, via the dithiocarbamate moiety. This method represents a potential alternative to current ones using the so-called bifunctional approach. In the second part of this manuscript, a new kit formulation for the 188Re labeling of lipiodol is described, using a complex analogous to those described in the previous part. The labeled oil is a potential cure for hepatocellular carcinoma. The in vitro and in vivo stability of this 188Re-SSS lipiodol and of its analogue 99mTc-SSS lipiodol has been studied, and also their in vivo behavior in healthy pigs. This study has shown the quasi-exclusive hepatic fixation of the radiopharmaceutical, and has proven its good stability. Its selectivity for tumors remains to be shown before trying it on humans. (author)

  6. The technetium-99m DTPA partition test in the diagnosis of tuberculous meningitis

    Although the blood/cerebrospinal fluid (CSF) bromide concentration ratio is sensitive and specific in the diagnosis of tuberculous meningitis (TBM), bromide-82 is not always available since it is not generally used in nuclear medicine. The use of technetium-99m diethylenetriamine penta-acetic acid (DTPA) for a partition test was compared with that of 82Br in 22 cases. Seven patients were diagnosed as having TBM, 9 patients had viral meningitis and 5 patients had septic meningitis. One normal control subject was also studied. Although the mechanism of transfer of substances across the blood-brain barrier as well as the factors affecting it are still unclear, both 82Br and 99mTc-DTPA cross the blood-brain barrier to a greater extent in TBM than in viral meningitis. Both tracers thus yield decreased serum/CSF concentration ratios in TBM. The accuracy of the 82 Br partition test was found to be 90,9% if a critical serum/CSF ratio of 1,3 was chosen, compared with 86,9% for the 99mTc-DTPA partition test if a critical value of 3 was chosen. The use of 99mTcDTPA offers various advantages, including general availability, lower cost and radiation dose per MBq, as well as the possibility of concomitant brain scintigraphy. 1 tab., 9 refs

  7. Technetium-99m-Sestamibi in the diagnosis of acute chest pain

    Full text: A 45-year-old male was admitted to coronary care with a two-day history of recurrent chest pain. Despite maximal medical therapy, pain persisted. Examination and ECG with pain, were normal, suspicion of ischaemia was moderately high but coronary angiography was not immediately available. Technetium-99m-Sestamibi was prepared at the start of the day according to the standard preparation protocol (Du Pont). Coronary Care informed the Nuclear Medicine Department immediately the patient experienced a further episode of chest pain. Technetium-99m-Sestamibi was administered in coronary care, 4.30 minutes after being advised of the onset of further chest pain. Images were acquired 60 minute post-injection; 15 minutes after the patient had been given 200 mL of milk. A triple-headed gamma camera was used to acquire SPECT images over a 1200 arc, 30 frames of 30 seconds using a 64 x 64 matrix. The patient was laying prone with arms raised out of the field of view. Images showed a normal distribution of technetium-99m -Sestamibi throughout the myocardium. Due to ongoing clinical suspicion by the treating physician, coronary angiography was subsequently performed. This showed normal coronary arteries. Medical therapy was ceased and the patient discharged the next day. We concluded that the chest pain at the time of injection was not ischaemic. Previous trials had shown a 95% sensitivity for this method of diagnosing ischaemia. This method permits a novel and simple technique for diagnosing myocardial ischaemia and obviating the need for cardiac catheterization in this group of patients

  8. A comparative study of technetium-99m sestamibi and technetium-99m tetrofosmin single-photon tomography in the detection of nasopharyngeal carcinoma

    The intention of this prospective study was to compare the diagnostic potential of technetium-99m sestamibi (MIBI) and a novel radiotracer, 99mTc-Tetrofosmin (Tetro), for the assessment of primary nasopharyngeal carcinoma (NPC) and the differentiation of residual disease from post-therapy changes. A total of 38 patients underwent MIBI and Tetro single-photon emission tomography (SPET) imaging at initial presentation (n=22) or following therapy (n=16). The findings were correlated with computed tomography or magnetic resonance imaging (MRI) on a site-by-site basis. Tumour/background (Tm/Bkg) ratios were obtained on coronal sections. Biopsy (nine patients) and/or 12- to 24-month clinical follow-up data were available in the post-therapy group. All primary disease sites were accurately detected by both imaging studies. Although there was no statistical difference between the two imaging techniques in the detection of primary disease, MIBI was superior to Tetro in the detection of regional lymph node metastases (sensitivity: 95% vs 79%). Tetro and MIBI SPET were true-positive in all patients (n=7) with proven residual/recurrent disease. In nine patients who had no evidence of residual/recurrent tumour, MRI was false-positive in five while Tetro and MIBI SPET were false-positive in two and three patients, respectively. Tm/Bkg ratios were ≤1.7 in all false-positive cases except one. Tetro, MIBI and MRI had specificities of 78%, 67% and 44%, and accuracies of 87.5%, 81% and 69%, respectively. The results of Tetro and of MIBI SPET were not statistically different from one another with regard to the prediction of residual/recurrent or metastatic NPC. (orig.). With 3 figs., 4 tabs

  9. The use of technetium-99m-DTPA in the diagnosis of tuberculous meningitis

    As 82Br is not available locally in South West Africa on a daily basis a technetium preparation, 99mTc-DTPA, was used in the diagnosis of patients with tuberculous meningitis. The 99mTc-DTPA partition test was compared with the 82Br partition test on 22 trial subjects. The trial subjects varied in age (0,8-57 years), sex and race. There were 7 patients diagnosed by the clinicians as having tuberculous meningitis. All patients were placed on anti-tuberculous meningitis treatment and all, except 2, one of whom regressed and 1 who died 7 days later, improved slowly. The 9 patients with viral meningitis received no antibiotics and recovered rapidly on symptomatic treatment only. With all 5 the septic meningitis cases, the organism was identified and there was thus no diagnostic uncertainty. One normal control subject was also examined. It would appear from the results that both 82Br, as well as 99mTc-DTPA, cross the blood-brain barrier to a greater extent in the case of tuberculous meningitis, compared to viral meningitis. Although the accuracy of the 82Br test, if a critical ratio value of 1,3 was chosen, is 90,6% compared to 86,9% of the 99mTc-DTPA partition test if a critical ratio value of 3 was chosen, there are still advantages to the use of the technetium preparation. These include the availability, cost and lower radiation dose per MBq as well as the possibility of brain imaging. 10 figs., 58 refs., 9 tabs

  10. Technetium-99m pyrophosphate imaging in acute renal failure associated with nontraumatic rhabdomyolysis

    Patel, R.; Mishkin, F.S.

    1986-10-01

    Technetium-99m pyrophosphate (Tc-PYP) imaging was performed in five patients with acute renal failure associated with nontraumatic rhabdomyolysis. Four patients had phencyclidine intoxication and one had viral pneumonia. During the acute phase, marked uptake of pyrophosphate was seen in all patients in several muscle groups, but always in the thigh adductors. The results show that phencyclidine intoxication can result in diffuse muscle uptake of Tc-PYP without overt evidence of muscle injury. Tc-PYP imaging may provide a clue to the cause of acute renal failure in patients with suspected rhabdomyolysis in whom elevations of serum creatine phosphokinase concentrations are equivocal.

  11. Technetium-99m pyrophosphate imaging in acute renal failure associated with nontraumatic rhabdomyolysis

    Technetium-99m pyrophosphate (Tc-PYP) imaging was performed in five patients with acute renal failure associated with nontraumatic rhabdomyolysis. Four patients had phencyclidine intoxication and one had viral pneumonia. During the acute phase, marked uptake of pyrophosphate was seen in all patients in several muscle groups, but always in the thigh adductors. The results show that phencyclidine intoxication can result in diffuse muscle uptake of Tc-PYP without overt evidence of muscle injury. Tc-PYP imaging may provide a clue to the cause of acute renal failure in patients with suspected rhabdomyolysis in whom elevations of serum creatine phosphokinase concentrations are equivocal

  12. Technetium-99m-HMPAO SPECT in patients with hemiconvulsions followed by Todd's paralysis

    We performed technetium-99m-hexamethylpropylene- amineoxime (Tc-HMPAO) single photon emission computed tomography in two patients with prolonged hemiconvulsions followed by transient hemiparesis (Todd's paralysis). In both cases, a prolonged post-ictal cerebral hyperperfusion state of approximately 24 h was observed, even after the neurological deficits had resolved. The cerebral hyperperfusion in both cases was of much longer duration than that in previously reported cases of single and uncomplicated focal seizures. The prolonged cerebral hyperperfusion might have been due to impairment of the cerebrovascular autoregulation in seizures followed by Todd's paralysis. (orig.)

  13. Optimising technetium 99m diethylenetriaminepenta-acetate lung clearance in patients with the acquired immunodeficiency syndrome

    Pneumocystis carinii pneumonia (PCP) has become a major cause of morbidity and mortality due to infectious diseases, largely as a result of the acquired immunodeficiency syndrome (AIDS) epidemic. Since the mortality from recurrent infection is between 40% and 60%, early diagnosis and therapy are the keys to survival. The role of technetium 99m diethylenetriaminepentacetate (DTPA) aerosol pulmonary clearance was studied in 81 patients with AIDS. The mathematical technique of curve stripping was found to be the optimal method of analysis and to provide an overall sensitivity of 94% for the detection of interstitial pneumonitis. The procedure was superior to standard pathology parameters and radiography and more convenient than gallium 67 scintigraphy. (orig.)

  14. Technetium-99m-HMPAO SPECT in patients with hemiconvulsions followed by Todd`s paralysis

    Kimura, M.; Sejima, Hitoshi; Ozasa, Hiroshi; Yamaguchi, Seiji [Department of Pediatrics, Shimane Medical University, 89-1 Enya-cho, Izumo, Shimane 693 (Japan)

    1998-02-01

    We performed technetium-99m-hexamethylpropylene- amineoxime (Tc-HMPAO) single photon emission computed tomography in two patients with prolonged hemiconvulsions followed by transient hemiparesis (Todd`s paralysis). In both cases, a prolonged post-ictal cerebral hyperperfusion state of approximately 24 h was observed, even after the neurological deficits had resolved. The cerebral hyperperfusion in both cases was of much longer duration than that in previously reported cases of single and uncomplicated focal seizures. The prolonged cerebral hyperperfusion might have been due to impairment of the cerebrovascular autoregulation in seizures followed by Todd`s paralysis. (orig.) With 2 figs., 9 refs.

  15. Comparison of technetium-99m-HMPAO and technetium-99m-ECD cerebral SPECT images in Alzheimer`s disease

    Dyck, C.H. van; Lin, C.H.; Smith, E.O. [Yale Univ. School of Medicine, New Haven, CT (United States)] [and others

    1996-11-01

    SPECT has shown increasing promise as a diagnostic tool in Alzheimer`s disease (AD). Recently, a new SPECT brain perfusion agent, {sup 99m}Tc-ethyl cysteinate dimer ({sup 99m}Tc-ECD) has emerged with purported advantages in image quality over the established tracer, {sup 99m}Tc-hexamethylpropyleneamine oxime ({sup 99m}Tc-HMPAO). This research aimed to compare cerebral images for ({sup 99m}Tc-HMPAO). This research aimed to compare cerebral images for {sup 99}mTc-HMPAO and {sup 99m}Tc-ECD in discriminating patients with AD form control subjects. 51 refs., 5 figs., 3 tabs.

  16. Yields of tricarbonyl complexes of technetium-99m and rhenium-188 on +1 oxidation state - comparative study

    The synthesis of tricarbonyl complexes of technetium-99m and rhenium-188 with bidentate ligands with N,S and N,O donor atoms was presented. The stability of the obtained complexes was compared. The study showed that technetium complexes with N,S donor atoms ligands are more stable. Rhenium forms more stable complexes with N,O donor atoms ligand. (author)

  17. Minimizing Molybdenum 99 contamination in Technetium 99m Pertechnetate from the elution of 99Mo/ 99m Tc Generator

    Radioisotope Tc-99m is widely used for variety of nuclear medicine diagnostic procedures. For many commercial applications, it is prepared in a portable type generator. Nuclear Malaysia has been producing a dry type alumina chromatographic column generator utilizing fission Mo-99. This injectable Tc-99m must meet the British Pharmacopeia [1] product specification prior to be apply on patient. This paper provides a method to minimize the up to acceptable level Mo-99 in the final product. Purposely made pertechnetate contaminated with Mo-99 and re-eluate by using old generator. Excellent removal of Mo-99 impurity was achieved and more than 80 % of Tc-99m total activity was recovered. (author)

  18. Kinetic investigations of sup(99m)Tc-labelled radiopharmaceuticals

    Several radiopharmaceuticals (sup(99m)Tc-Fe-ascorbates, sup(99m)Tc-Sn-DTPA, sup(99m)Tc-Sn-ACD-citrate-complex and sup(99m)Tc-Sn-tetracyclin-HAsc-ACD-complex) for renal and tumour scintigraphy were tested in animal experiments. Also tested was sup(99m)Tc-penicillamine for scintigraphic investigations of the gallbladder and the liver. The findings suggest that the different radiopharmaceuticals have different degrees of reliability and exactness, and that some of them should be combined to achieve better diagnostic values. (GSE/AK)

  19. Effect of passiflora quadrangularis extracts on the technetium-99m biodistribution in mice

    Medicinal plants have been evaluated and their effect on the biodistribution of radiopharmaceuticals are very important. This work aims to evaluate the interaction of extracts of Passiflora quadrangularis on the biodistribution of 99mTc in mice (Mus musculus). The animals were submitted to brief treatment with aqueous (G1) and hydroalcoholic 10% (G2) extracts. Control animals received saline solution 0.9% (n=5). The reaction 99mTc (3.7 MBq) in the presence of stannous chloride and extracts was incubated for 10 minute, then it was injected (ip way) in mice. At the end of 30 minutes, animals were sacrificed for removal of organs and 0.5 mL of blood, which were counted in gamma counter. The percentage of 99mTc-binding was calculated in relation to the weight of each organ. The results show a reduction on right and left kidneys in the presence of aqueous extract at about 26.74%, and more significant reduction in the presence of hydroalcoholic 10% extract at about 72.81%. the trachea presents a binding capacity to 99mTc in order of 263.5% in the presence of aqueous extract. These results demonstrate that 99mTc presents affinity to some organs and that the extract of Passiflora quadrangularis is able to alter this labeling. Therefore, more attention has been given to diagnoses with pharmaceutical compounds labeled with radioisotopes. (author)

  20. Evaluation of ethinylestradiol effect on labelling red blood cells with Tc-99m; Avaliacao do efeito do etinilestradiol sobre a marcacao de hemacias com tecnecio-99m

    Braga, A.C.S.; Oliveira, J.F.; Santos, J.S.; Oliveira, M.B.N.; Gutfilen, B.; Bernardo-Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Dept. de Biofisica e Biometria

    1999-11-01

    Significant alterations on the radiopharmaceutical distribution in humans are caused by drug interactions. The labeling red blood cells with technetium-99m is a daily routine procedure in nuclear medicine. Here, we investigated if the ethinylestradiol, an oral contraceptive, could alter the labeling of RBC with Tc-99m. Samples of blood with acid citrate dextrose were incubated with ethynilestradiol. Then, different concentrations of Sn C L{sub 2} were added and, after that, Tc-99m was added. Samples were centrifuged and plasma (P) and cells (C) were separated. the results showed that the drug studied decreased the uptake of radioactivity (%ATI) in the C to the reducing agent in the concentration of 1.2 (from 92.3 to 78.0) and increased in 12.0 (18.8 to 36.0) and in 24.0 (22.8 to 32.0){mu}/ml of Sn C L{sub 2}. The obtained results can be explained by the fact that this drug could alter the membrane permeability to the transport of stannous and/or pertechnetate ions. (author) 18 refs., 2 tabs.

  1. Stabilization of an injection preparation of technetium-99m MDP with ascorbic acid

    Tc-99m-labelled preparations for bone scanning are subject to oxidation in vitro. This results in bad scans with images of soft tissues as well. Three commercially available preparations were tested for stability after addition of ascorbic acid which effectively counteracts the oxidation by dissolved oxygen. (Auth.)

  2. Iterative reconstruction: an improvement of technetium-99m MIBI SPET for the detection of parathyroid adenomas?

    Moka, D.; Eschner, W.; Voth, E.; Dietlein, M.; Schicha, H. [Dept. of Nuclear Medicine, University of Cologne (Germany); Larena-Avellaneda, A. [Dept. of Surgery, St. Katharinen-Hospital, Frechen (Germany)

    2000-05-01

    The purpose of this study was to assess the value of technetium-99m methoxyisobutylisonitrile (MIBI) single-photon emission tomography (SPET) and an iterative reconstruction algorithm for the preoperative localisation of parathyroid adenomas (PTAs). Seventy-two patients (26 male, 46 female, mean age 58{+-}16 years) with known primary hyperparathyroidism were examined preoperatively. First, a thyroid examination was performed to detect possible MIBI-accumulating thyroid lesions. Planar scans were then acquired 15 and 120 min and tomographic images 120 min after intravenous injection of 740 MBq {sup 99m}Tc-MIBI, using a triple-head gamma camera (Picker Prism 3000). Additionally, {sup 99m}Tc-MIBI/ {sup 99m}Tc-pertechnetate subtraction scintigraphy of the early planar images was performed. The SPET data were evaluated using an iterative reconstruction (multiplicative iterative SPET reconstruction: MISR) as well as a standard algorithm (FBP: filtered back-projection with application of a 3-D low-pass postfilter). The weight of the resected PTAs ranged from 110 mg to 5 g. Using planar MIBI scans, correct localisation of the side of the PTA was possible in 81% of cases (58% for PTAs weighing less than 500 mg). Sensitivity increased to 94% using SPET and FBP, while with MISR it rose further, to 97%. Patients with PTAs weighing less than 500 mg showed a sensitivity of 88% with MISR and 81% with FBP. Furthermore, there was a clear improvement in image quality using MISR. None of the normal parathyroid glands were visualised. This study indicates that, in comparison with planar scintigraphy, {sup 99m}Tc-MIBI SPET is a more sensitive and specific tool for topographical localisation of PTAs, especially those that are small. There is a further improvement in sensitivity and image quality when iterative reconstruction is used instead of FBP. (orig.)

  3. Development and evaluation of a kit lyophilized of 99mTc labelled macroaggregated albumin, for pulmonary perfusion imaging

    The development of a lyophilized kit of macroaggregated albumin is showed in this work. The product obtained is labelled with 99mTc and it was used in pulmonary perfusion scintigraphy. The albumin was denaturalized under control conditions of heating and stirring, then washed to eliminate small particles (oC to 25 oC. The lyophilized product was labelled by 99mTc and obtained 99mTc-MAA complex, with a radiochemical purity more than 97%, the results of the biological studies obtained more than 92 % of the injected doses in the lungs. Another study was about stability in real time, it showed stability for 18 months. In the clinic studies, the labelled complex showed a good pulmonary perfusion and absence of free technetium. (author)

  4. Evaluation of bone-marrow scanning with technetium-99m sulfur colloid in pediatric oncology

    Eighty-six technetium-99m sulfur colloid (Tc-SC) bone-marrow scans in 56 pediatric oncology patients were reviewed. The distribution of the sulfur colloid was similar to that in adult bone marrow in normal children older than 10 yr, and involved progressively more marrow of the extremities in normal children under 10 years of age. After irradiation or chemotherapy there was an extension of the Tc-SC to peripheral marrow sites. There was also diminished uptake of the tracer in sites corresponding to irradiated areas. In most patients there was recovery of these defects by 6 mo after completion of therapy. Tumor replacement of the marrow was reflected in the scans, and the extent of the scan defect paralleled the course of the disease. In four patients, despite normal bone scans and radiographs, marrow-scan abnormalities due to tumor replacement were present and confirmed by needle aspiration and/or biopsy. In two other patients, the marrow-scan abnormality preceded radiographic and histologic evidence of tumor metastasis. Two patients who responded clinically showed persistent defects; biopsy in one revealed fibrosis. Technetium-99m sulfur colloid bone-marrow scanning appears to be a sensitive monitor of marrow alteration caused by metastases, irradiation damage, or tissue fibrosis in children receiving treatment for cancer

  5. Technological aspects of production of technetium- 99m chromatography generators from enriched molybdenum-98

    Full text: The objective of this work is to create without waste manufacturing of generators technetium-99m based on enriched molybdenum-98. Main problems of this technology connected with the low specific of activity of the radioactive nuclide 99Mo. For the reactors with thermal neutrons density 1 ·1014 n/sm2 s is usually less than 8 Ci/g. It causes necessity to mark more molybdenum (100 mg and more) to generators column. At IRT-T reactor carried out researches of radioactive capture reaction at molybdenum-98 using resonance neutrons. During variation of beryllium slower blocks configuration effective section of reaction in the zone irradiation of molybdenum targets was increased up to 700 mb [1]. It also was considered the task to prepare absorbers to provide safety 'connecting' of carrying source into stable molybdenum-98. We researched and have got data about influence of adsorbable molybdenum to yield of technetium-99m exit from generator. This manufacture created at IRT-T reactor meets requirements of international standards (GMP) and it's almost without waste. Summary activity of wastes is less then 10-4 % from total activity of getting 99Mo. In the same time traditional technologies have the same exponent as 4000%

  6. Technetium-99m tetrofosmin for parathyroid scintigraphy: a direct comparison with {sup 99m}Tc-MIBI, {sup 201}Tl, MRI and US

    Wakamatsu, Hideyuki [Dept. of Radiology, Noguchi Thyroid Clinic and Hospital Foundation, Oita (Japan); Noguchi, Shiro; Yamashita, Hiroyuki [Dept. of Surgery, Noguchi Thyroid Clinic and Hospital Foundation, Oita (Japan); Yamashita, Hiroto [Dept. of Pathology, Noguchi Thyroid Clinic and Hospital Foundation, Oita (Japan); Tamura, Shozo; Jinnouchi, Seishi; Nagamachi, Shigeki; Futami, Shigemi [Dept. of Radiology, Miyazaki Medical College, Miyazaki (Japan)

    2001-12-01

    The aim of this study was to evaluate the efficacy and role of technetium-99m tetrofosmin for the detection of abnormal parathyroid glands to be referred for surgical treatment. Twenty-eight consecutive patients, including 25 primary and 3 secondary cases of hyperparathyroidism, were evaluated. {sup 99m}Tc-tetrofosmin/{sup 99m}Tc-pertechnetate subtraction scintigraphy (TF/Tc) was performed on all patients, and the results were directly compared with those of {sup 99m}Tc-methoxyisobutylisonitrile (MIBI)/{sup 99m}Tc-pertechnetate subtraction scintigraphy (MIBI/Tc), {sup 201}Tl/{sup 99m}Tc-pertechnetate subtraction scintigraphy (Tl/Tc), magnetic resonance imaging (MRI) and ultrasonography (US). In cases of single-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 63.2%, 68.4%, 57.9%, 55.6% and 63.2%, respectively. In cases of multi-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 41.7%, 41.7%, 37.5%, 58.3% and 54.2%, respectively. In cases of parathyroid adenoma, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 68.8%, 75.0%, 68.8%, 62.5% and 75.0%, respectively. In cases of parathyroid hyperplasia, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 40.7%, 40.7%, 33.3%, 53.8% and 48.1%, respectively. It is concluded that, for the detection of abnormal parathyroid glands, {sup 99m}Tc-tetrofosmin is as useful as {sup 99m}Tc-MIBI and is more useful than {sup 201}Tl. (orig.)

  7. Labelling and quality control of 99mTc labelled somatostatin analogues

    To standardize interlaboratory reproducibility, iodination of RC-160 with 125I and direct labelling of RC-160 with 99mTc, quality control and binding assay were performed. Two conjugated peptides, HYNIC-RC-160 and MAG-3-RC-160, were synthesized. The conjugated peptides were radiolabelled with 99mTc via co-ligands; 99mTc-MAG-3-RC-160 via glucoheptonate, 99mTc-HYNIC-RC-160 via EDDA and tricine. Conditions for labelling were optimized. Analytical and purification methods for the labelled products were developed. Radiochemical purity test of 99mTc labelled peptides was performed by HPLC with gradient elution of 0.1%TFA/water and acetonitrile, or by ITLC-SG in saline and in 50% acetonitrile. The contaminants in 99mTc radiolabelled product were separated by elution from SEPPAK C-18 cartridge by 0.1% acetic acid and the pure product was eluted out of SEPPAK column by 50% acetonitrile with about 68% recovery. Stability of the purified 99mTc-MAG3-RC-160 stored at -20 deg. C was more than 72 h. 99mTc-MAG-3-RC-160 showed a high equilibrium dissociation constant with KD of 26 pmole/mg protein and Bmax of 7.9 mM. (author)

  8. 99m-technetium tetrofosmin and 99mTc-methylene diphosphonate in pre-surgical breast cancer

    Full text: The aim of this study was to assess the role of the Tc-99m Tetrofosmin (TF) in conjunction with Tc-99m methylenediphosphonate (MDP) in pre-surgical breast cancer (BC) staging. Thirty-six female patients, age range was 32-70 years (average 51.45 years), where the clinical examination, mammography (MG) and fine-needle aspiration cytology were inconclusive were subjected to Tc-99m TF Scintimammography (SMM). All the patients were examined in a specialized breast clinic by experienced surgeons and radiologists. Of the 36 patients, 24 had hyperdense breasts, 8 had undergone lumpectomy or mastectomy due to cancer in one of the breasts and were included in the present study because of suspicion of lesion in the contra lateral breast, 2 had palpable axillary lymph nodes (LN) but no palpable breast lump and 2 patients were of mastitis carcinomatosis. All biopsies were histopathologically verified 740 MBq of Tc-99m TF (Myoview-Amersham) was injected in the arm opposite to the side of the breast lesion. In patients with bilateral breast lesions (BL) radiopharmaceutical was injected in a pedal vein. Planar imaging in prone position was done 10-15 min later. Two lateral views of the left and right breasts including axilla were acquired followed by an anterior view in supine position with arm in an upright position so as to include both breasts and axillary region in the field of imaging view. Imaging was done using a large field of view single-head gamma camera (Diacam-Siemens) coupled with low-energy high-resolution collimator. In patients with locally advanced BC who were to receive pre-operative neo-adjuvant chemotherapy, cardiac GATED SPECT was also acquired using standard protocol. After few days, Tc-99m MDM scintimammography and whole-body bone scintigraphy was also performed. SMM, using the same acquisition protocol as with 99mTc-TF, was done 5-10 min after intravenous injection of 555-740 MBq 99mTc MDP. Standard WBBS was acquired two to three hours later. SMM

  9. Indium-111 myosin-specific antibodies and technetium-99m pyrophosphate in the detection of acute cardiac rejection of transplanted hearts

    111In-labelled myosin-specific antibodies were evaluated as an indicator of early changes in acute rejection in a rat heart heterotopic transplant model. Uptake of antibodies was measured in allograft and isograft hearts of animals undergoing different regimens of cyclosporine treatment and compared with the uptake of technetium 99m pyrophosphate. The data were correlated with histological estimation of the severity of myocyte necrosis and sign of early rejection (venous cuffing and endocardial inflammation, indicators of perivascular infiltrate and intermyocyte extension, respectively). Myocyte necrosis in transplanted hearts was reflected by increases in technetium 99m pyrophosphate accumulation (r=0.88) but was poorly correlated with labelled antibody uptake (r=0.58). There was no positive correlation between the degree of early cardiac rejection and uptake of either of the radiopharmaceuticals: accumulation of the labeled antibodies paradoxically declined with increased histological severity scores, whereas that of technetium 99m pyrophosphate remained unchanged. Cyclosporine treatment augmented the uptake of labelled antibodies in transplanted hearts. This may be due to alterations in plasma membrane permeability brought about by the drug, resulting in a rise in antibody binding to intracellular myosin. (orig.)

  10. Influence of splenectomy on the biodistribution of technetium-99m dimercaptosuccinic acid (99mTc-DMSA) in rats

    This study aimed to evaluate if the splenectomy alters the biodistribution of 99mTc-DMSA and renal function in Wistar rats. The animals were separated in the groups: splenectomy (n = 6) and control (n = 6). After splenectomy (15 days), the administration of 0.1 ml of 99mTc-DMSA IV (0.48 MBq) was carried out. Thirty minutes later, kidney, heart, lung, thyroid, stomach, bladder and femur and samples of blood were isolated. The organs were weighed, counted and the percentage of radioactivity /g (%ATI/g) determined. Serum urea and creatinine, hematocrit, leukocytes and platelets were measured. Statistics by t test (p<0.05) was done. There was a significant reduction in %ATI/g in kidney and blood (p<0.05) of splenectomized animals, a significant increase (p<0.05) of urea (88.8 ± 18.6 mg/dL) and creatinine (0.56 ± 0.08 mg/dL), compared to the controls (51.5±1.6, 0.37±0.02 mg/dL, respectively), as well as increase in platelets and leucocytes, and hematocrit reduction. The analysis of the results indicates that in rats, splenectomy seems to alter the renal function and the uptake of 99mTc-DMSA. (author)

  11. Influence of splenectomy on the biodistribution of technetium-99m dimercaptosuccinic acid (99mTc-DMSA) in rats

    Acucena, Maria Kadja Meneses Torres; Pereira, Kercia Regina Santos Gomes; Villarim Neto, Arthur; Rego, Amalia Cinthia Meneses [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Ciencias da Saude; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Dept. de Biofisica e Biometria; Azevedo, Italo Medeiros; Araujo Filho, Irami; Medeiros, Aldo Cunha [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Cirurgia]. E-mail: aldo@ufrnet.br

    2008-12-15

    This study aimed to evaluate if the splenectomy alters the biodistribution of 99mTc-DMSA and renal function in Wistar rats. The animals were separated in the groups: splenectomy (n = 6) and control (n = 6). After splenectomy (15 days), the administration of 0.1 ml of 99mTc-DMSA IV (0.48 MBq) was carried out. Thirty minutes later, kidney, heart, lung, thyroid, stomach, bladder and femur and samples of blood were isolated. The organs were weighed, counted and the percentage of radioactivity /g (%ATI/g) determined. Serum urea and creatinine, hematocrit, leukocytes and platelets were measured. Statistics by t test (p<0.05) was done. There was a significant reduction in %ATI/g in kidney and blood (p<0.05) of splenectomized animals, a significant increase (p<0.05) of urea (88.8 {+-} 18.6 mg/dL) and creatinine (0.56 {+-} 0.08 mg/dL), compared to the controls (51.5{+-}1.6, 0.37{+-}0.02 mg/dL, respectively), as well as increase in platelets and leucocytes, and hematocrit reduction. The analysis of the results indicates that in rats, splenectomy seems to alter the renal function and the uptake of 99mTc-DMSA. (author)

  12. Influence of splenectomy on the biodistribution of technetium-99m dimercaptosuccinic acid (99mTc-DMSA in rats

    Maria Kadja Meneses Torres Açucena

    2008-12-01

    Full Text Available This study aimed to evaluate if the splenectomy alters the biodistribution of 99mTc-DMSA and renal function in Wistar rats. The animals were separated in the groups: splenectomy (n = 6 and control (n = 6. After splenectomy (15 days, the administration of 0.1ml of 99mTc-DMSA IV (0.48 MBq was carried out. Thirty minutes later, kidney, heart, lung, thyroid, stomach, bladder and femur and samples of blood were isolated. The organs were weighed, counted and the percentage of radioactivity /g (%ATI/g determined. Serum urea and creatinine, hematocrit, leukocytes and platelets were measured. Statistics by t test (pEstudo com objetivo de avaliar se a esplenectomia altera a biodistribuição do 99mTc-DMSA e alguns parâmetros bioquímicos e hematológicos em ratos Wistar. Os animais forma divididos em 2 grupos: esplenectomizados (n=6 e controle(n=6. Após 15 dias, administração de 0,1 ml de 99mTc-DMSA via plexo orbital (0,48 MBq foi realizada. Rim, coração, pulmão, tireóide, estômago, bexiga e fêmur e amostras de sangue foram separadas. Após pesagem e contagem da radioatividade foi determinado o percentual de radioatividade/g (% ATI/g. Dosadas uréia e creatinina sérica, hematócrito, plaquetas e leucócitos. Estatística pelo teste t, significância 0,05 foi realizada. Foi observada redução significante no %ATI/g no rim e sangue (p<0,05 dos animais esplenectomizados, aumento significante (p<0.05 da uréia (88,8±18,6 mg/dL e creatinina (0,56±0,08, comparado aos controles (51,5±1,6; 0,37±0,02mg/dL, respectivamente assim como aumento de leucócitos e plaquetas e redução de hematócrito. Conclui-se que em ratos, a esplenectomia alterou a captação de 99mTc-DMSA pelo rim, e a função renal.

  13. Regional cerebrocerebellar perfusion imaging in spinocerebellar degeneration using technetium-99m-HM-PAO

    Tanaka, Makoto; Inoue, Tomio; Kawarabayashi, Takeshi; Hirai, Shunsaku; Sasaki, Yasuhito

    1988-07-01

    A new rediopharmaceutical, technetium-99m hexamethylpropyleneamine oxime (/sup 99m/Tc-HM-PAO), has been reported to cross the blood-brain-barrier and to distribute in brain in proportion to regional blood flow. We report brain imaging with /sup 99m/Tc-HM-PAO using single photon emission computed tomography (SPECT) in 14 patients of olivopontocerebellar atrophy (OPCA), a subclass of spinocerebellar degeneration, and in 5 controls. In order to evaluate cerebellar blood flow semiquantitatively, the count ratio of cerebellar hemispheres to occipital cortex (C/O ratio) was compared to the regional blood flow ratio (PC/O ratio) obtained by quantitative positron emission tomography (PET) performed in 6 of the 14 patients. We also examined correlations between C/O ratio and clinical data such as duration of illness, clinical severity score, laterality of incoordination and atrophy score on X-ray CT. The results favored clinical usefulness of /sup 99m/Tc-HM-PAO. The C/O ratio in OPCA was significantly lower than in controls (p < 0.001) and close to PC/O ratio. In 7 out of 9 patients who showed constant asymmetric neurologic signs, cerebellar radioactivities were more reduced in the side where limbincoodination was more prominent. The C/O ratio and atrophic score on X-ray CT correlated significantly (p < 0.05). In a few cases, however, visible cerebellar hypoperfusion was demonstrated in spite of minimal cerebellar atrophy. There were no correlations between the C/O ratio and the other clinical data. Qualitatively the reconstructed sagittal image easily revealed cerebellar hypoactivity or hypoperfusion in OPCA because the occipital lobe and cerebellum appeared ajacently in a plane. (J.P.N.).

  14. Effects of radiofrequency ablation on individual renal function: assessment by technetium-99m mercaptoacetyltriglycine renal scintigraphy.

    Nasu,Yasutomo

    2006-04-01

    Full Text Available We quantitatively evaluated total and individual renal function by technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3 renal scintigraphy before and after radiofrequency ablation (RFA of renal tumors. Eleven patients who underwent Tc-99m MAG3 renal scintigraphy 1 week before and after RFA were evaluated (7 men and 4 women ; age range : 23-83 years ; mean age : 60.6 years. Five patients had solitary kidneys, and five had normally or minimally functioning contralateral kidneys. One patient had a renal cell carcinoma in the contralateral kidney. One patient with a solitary kidney underwent RFA a second time for a residual tumor. In patients with a solitary kidney, MAG3 clearance decreased after 5 of 6 RFAs, and in patients with a normally functioning contralateral kidney, MAG3 clearance decreased after 4 of 5 RFAs, but no significant differences were observed between before and after treatments. In addition to the total MAG3 clearance, the split MAG3 clearance was evaluated in patients with a normally functioning contralateral kidney. MAG3 clearance decreased in 4 of 5 treated kidneys, while it adversely increased in the contralateral kidneys after 4 of 5 RFAs. No significant differences, however, were observed between before and after treatments. The results of our study revealed no significant differences in sCr, BUN, CCr, or MAG3 clearance between pre- and post-RFA values. These results support data regarding the functional impact and safety of renal RFA in published reports. We evaluated total and individual renal function quantitatively using Tc-99m MAG3 renal scintigraphy before and after treatment. This scintigraphy was very useful in assessing the effects of RFA on renal function.

  15. 99mTc-Mesalamine as potential agent for diagnosis and monitoring of ulcerative colitis. Labelling, characterisation and biological evaluation

    Mesalamine was labelled with technetium-99m (99mTc) in high radiolabelling yield (∼98.4 %), in vitro stability (∼4 h) and in serum persistence (∼24 h). Optimum labelling conditions were investigated. The structure of the complex was confirmed using in silico analysis. Molecular docking was performed to evaluate the complex binding to its biochemical target, the PPARc receptor. Biodistribution and clearance studies were performed in normal and ulcerative colitis models in mice. The tracer's localization was highest (∼65.2 %) in microbial model compared to chemical model (∼42.4 %) and normal mice (∼22.1 %) at 60 min post injection. All data supported the usefulness of 99mTc-mesalamine as a radiotracer for ulcerative colitis. (author)

  16. Comparison of differential renal function using technetium-99m mercaptoacetyltriglycine (MAG3) and technetium-99m dimercaptosuccinic acid (DMSA) renography in a paediatric population

    In children who have undergone both 99mTc-DMSA and 99mTc-MAG3 studies for the assessment of differential renal function (DRF) and drainage, respectively, we have noticed good agreement between the calculated DRF values, and hypothesized that there is no significant difference in DRF values calculated from these tests. Therefore, both tests may not always be necessary. To determine whether there is a statistically significant difference between DRF values calculated using 99mTc-DMSA and those calculated using 99mTc-MAG3. We retrospectively identified children imaged with 99mTc-DMSA and 99mTc-MAG3. We recorded DRF values, age, indication, and renal pelvis diameter. For the 99mTc-DMSA studies we recorded the imaging time after injection. For the 99mTc-MAG3 studies we recorded the delay between injection and data acquisition, diuretic use and evidence of delayed drainage or reflux. We identified 100 episodes in 92 children where both 99mTc-DMSA and 99mTc-MAG3 scans had been performed within a few days. The commonest indication was urinary tract infection or pelviureteric junction obstruction. The mean age of the children was 6.96 years. A significant but clinically acceptable trend was seen between abnormal DRF and difference between tests. A significant link was found with the difference between tests and the time of imaging after DMSA injection, and also with scarring. No significant effect was caused by renal pelvis dilatation, delayed drainage, frusemide administration, or delayed 99mTc-MAG3 imaging. If a 99mTc-MAG3 study has been performed then a 99mTc-DMSA study is unnecessary provided DRF is normal on the 99mTc-MAG3 study and there is no scarring. A change in practice would lead to considerable savings in time, cost and radiation burden. (orig.)

  17. 99mTc-besilesomab (Scintimun registered) in peripheral osteomyelitis: comparison with 99mTc-labelled white blood cells

    The diagnosis of osteomyelitis is a challenge for diagnostic imaging. Nuclear medicine procedures including white blood cell imaging have been successfully used for the identification of bone infections. This multinational, phase III clinical study in 22 European centres was undertaken to compare anti-granulocyte imaging using the murine IgG antibody besilesomab (Scintimun registered) with 99mTc-labelled white blood cells in patients with peripheral osteomyelitis. A total of 119 patients with suspected osteomyelitis of the peripheral skeleton received 99mTc-besilesomab and 99mTc-hexamethylpropyleneamine oxime (HMPAO)-labelled white blood cells (WBCs) in random order 2-4 days apart. Planar images were acquired at 4 and 24 h after injection. All scintigraphic images were interpreted in an off-site blinded read by three experienced physicians specialized in nuclear medicine, followed by a fourth blinded reader for adjudication. In addition, clinical follow-up information was collected and a final diagnosis was provided by the investigators and an independent truth panel. Safety data including levels of human anti-mouse antibodies (HAMA) and vital signs were recorded. The agreement in diagnosis across all three readers between Scintimun registered and 99mTc-HMPAO-labelled WBCs was 0.83 (lower limit of the 95% confidence interval 0.8). Using the final diagnosis of the local investigator as a reference, Scintimun registered had higher sensitivity than 99mTc-HMPAO-labelled WBCs (74.8 vs 59.0%) at slightly lower specificity (71.8 vs 79.5%, respectively). All parameters related to patient safety (laboratory data, vital signs) did not provide evidence of an elevated risk associated with the use of Scintimun registered except for two cases of transient hypotension. HAMA were detected in 16 of 116 patients after scan (13.8%). Scintimun registered imaging is accurate, efficacious and safe in the diagnosis of peripheral bone infections and provides comparable information to 99mTc-HMPAO-labelled

  18. Effect of barbatimão [Stryphnodendron adstringens (Mart. Coville] infusion on the labling of blood elements with technetium-99m

    Thadeu E. M. Maramaldo Costa

    2002-01-01

    Full Text Available The Barbatimão is a tree which bark is rich in tannin. It is used on popular medicine as a wound healing agent, in the treatment of gastric lesions, as anti-leishmanial agent and as anti-inflammatory. Red blood cells (RBC are labeled with technetium-99m (Tc-99m and are utilized in many procedures in nuclear medicine. Some authors have reported that drugs (natural and synthetic can alter the labeling of RBC with Tc-99m. This study evaluates the effect of barbatimão infusion on the labeling of red blood cells (RBC and plasma (P proteins with Tc-99m. Heparinized blood from Wistar rats was incubated with NaCl 0.9% as control and different concentrations of barbatimão infusion. Following the addition of stannous chloride (SnCl2, as reducing agent, and Tc-99m, as sodium pertechnetate, the blood samples were centrifuged. P and RBC were separated and were also precipitated with trichloroacetic acid 5%. Insoluble (IF-P and IF-RBC fractions were isolated. The percentage of radioactivity in all the samples was determined. All the barbatimão infusion concentrations decreased the labeling of RBC, IF-P and IF-RBC. We can speculate that the barbatimão infusion interfered on the labeling of RBC due to the redox properties and/or it can also act as a chelator of the stannous ion.

  19. 99mTc-labelled minigastrin for tumour targeting: Optimization of labelling and peptide sequence

    Full text: carcinoma (MTC), neuroenteropancreatic tumours (NET) and small cell lung caner (SCLC). Therefore Gastrin analogues binding to the CCK-2 receptor are promising candidates for Nuclear Medicine imaging. Recently a Minigastrin derivative (eEEEEEAYGWMDF) has been labeled with 131I, 111In and 90Y and evaluated in patients. However, due to its availability and optimal decay properties 99mTc would still be the radionuclide of choice for diagnostic applications. This paper describes the development of a 99mTc analogue and the optimisation of radiolabelling approaches and peptide sequence for targeting Gastrin/CCK receptor positive cells in vivo. Two MG sequences, eEEEEEAYGWMDF (MG0) and eAYGWMDF (MG11) were derivatized both with HYNIC at the aminoterminus as well as MG0 with a HIS derivative ((Nα-His)Ac) for Tc-Carbonyl labelling. Labelling was perfomed at high specific activities (>1Ci/μmol) using Tricine and EDDA as coligands for HYNIC-MG0, HYNIC-MG11 and [99mTc(OH2)3(CO)3]+ for (Nα-His)Ac-MG0. Stability experiments were carried out by RP-HPLC analysis in PBS, serum, histidine- and cysteine-solutions as well as rat liver and kidney homogenates. Plasma protein binding was determined by use of size exclusion chromatography using Microspin columns. Competition experiments of unlabeled conjugates on CCK-2 receptor positive AR42J membranes versus [125I]-Tyr12-Gastrin I were used to determine receptor affinity for unlabelled conjugates under study. Receptor binding and internalisation experiments with the radiolabelled derivatives were performed also using AR42J rat pancreatic cells. Biodistribution experiments were carried out in nude mice carrying AR42J tumours by injection of 99mTc-labeled peptide with or without coinjection of 50μg cold MG. At specific activities >1Ci/μmol both MG1 and MG11 could be labelled with yields >95% independently of the labelling approach and peptide sequence. Lipophilicity as determined by HPLC was in the order 99mTc-HYNIC-MG11>99m

  20. Intraoperative injection of technetium-99m-dextran 500 for the identification of sentinel lymph node in breast cancer

    Purpose: to determine the efficacy of intraoperative injection of Dextran-500-99m-technetium (Tc) for the identification of the sentinel lymph node (SLN) in breast cancer and analyze time to label the SLN in the axillary region. Methods: a prospective study between April 2008 and June 2009, which included 74 sentinel lymph node biopsies (SLNB) in patients with breast cancer in stages T1N0 and T2N0. After induction of anesthesia, 0.5 to 1.5 mCi of Dextran-500-99m-Tc filtered 0.22 μm in a volume of 5 mL was injected intraoperative using the subareolar technique for SLNB. After labeling with the radioisotope, 2 mL of patent blue was injected. The time elapsed between injection and the axillary hot spot, the in vivo and ex vivo counts of the hottest nodes, the background count, and the number of SLN identified were documented. Data were analyzed using descriptive statistics with SPSS program, version 18. Results: we identified the SLN in 100% of cases. The rate of SLN identification with the probe was 98% (73/74 cases). In one case (1.35%) the SLN was labeled only with the blue dye. The mean dose of radioisotope injected was 0.97±0.22 mCi. The average time to label the SLN was 10.7 minutes (±5.7 min). We identified on average of 1.66 SLN labeled with the radioisotope. Conclusion: the procedure for SLN identification with an intraoperative injection of the radioisotope is oncologically safe and comfortable for the patient, providing agility to the surgical team. (author)

  1. The feasibility of a renogram study in dogs with radiopharmaceutical technetium 99m-DTPA

    The present study is one of in vivo technetium 99m-DTPA renography, successively involving conscious healthy dogs under acepromazine maleate sedation and dogs under the narcotic sodium thiopental. It was found that during the running of the renogram the animal had to be kept completely immobile and that constant infusion narcosis with sodium thiopental produced this immobility without affecting the renograms unduly. However administration of a thiopental bolus did have an adverse effect on the renogram. Sedation with acepromazine maleate significantly increased the time to peak and the excretion phase as presented by the slope. These effects are thought to be due to a decreased blood pressure with concomitant renal bloodpooling and retarded bloodflow. The radioisotope renogram appears to hold great promise for both clinical and research applications. The equipment required for this application however, is so costly that it would only be financially feasible for major centres

  2. Acute myocardial infarction. Clinical application of technetium 99m stannous pyrophosphates infarct scintigraphy

    Acute myocardial infarction is being recognized as a spectrum of clinical subsets. This appreciation has been brought about to a large degree by the development of several new tools that can be applied clinically to aid in evaluation of patients with acute infarction, and in some cases to provide short- and long-term prognostic information. In the realm of noninvasive methods, several tests utilizing radiopharmaceuticals and scintillation cameras have emerged and are rapidly becoming reliable diagnostic parameters in patients with coronary disease and infarction. Technetium-99m (stannous) pyrophosphate (TcPYP) scintigraphy, one of the first of these techniques to find clinical use, has been shown to be an accurate indicator of acute transmural myocardial infarction and provides added sensitivity and specificity to the diagnosis. Increased diagnostic accuracy, the dimension of visible localization, and the potential for infarct sizing promise physicians better understanding of a patient's clinical presentation and a more rational approach to management

  3. Radiolabeling of Ciprofloxacin with Technetium-99 m, quality control and biodistribution

    Radiolabeled antibiotics are used for the specific diagnosis of infection by exploiting their specific binding properties to the bacterial components, thereby making it possible to differentiate infection from sterile lesions. 99mTc-ciprofloxacin is the most widely used infection imaging agent which belongs to quinolones group and has a vast antimicrobial action against bacteria's. Ciprofloxacin binds to bacterial DNA Gyrase and inhibits its conventional synthesis. Ciprofloxacin labeled with 99mTc specifically binds to various bacteria. Thus, it potentially constitutes a specific marker allowing discrimination between septic and aseptic diseases. In this paper, we describe the labeling of ciprofloxacin with the most widely used imaging radionuclide, 99mTc. The quality control procedure using thin layer chromatography and the stability of labeled compound and also the effect of different parameters such as p H and stannous chloride amount on the radiolabeling yield were investigated. The maximum radiochemical yield was 90±3%. The stability of the radiolabeled antibiotic in the presence of human serum was about 84.2% and 79.6%, respectively after 1 h and 4 h. 75% of the activity binds to the plasma proteins and the ratio of infected muscle to non-infected muscle is 3.2 and 1.8, 1 h and 4 hours post injection.

  4. Clinical studies of alveolar-capillary permeability using technetium-99m DTPA aerosol

    Soluble radioaerosols such as technetium-99m diethylene triamine pentacetate (DTPA) permit simple quantitative studies of alveolar-capillary permeability to be performed, since the submicronic aerosols are deposited mainly at the lung periphery and are cleared across the alveolar-capillary membrane. Regional alterations in permeability can also be noted using this radionuclide technique. We have measured the pulmonary epithelial permeability in normal subjects and the alteration in smokers, glue-sniffers, patients with inhalation burns, chronic obstructive pulmonary disease (COPD) and patients with lung metastases from thyroid cancer treated with radioiodine 131I. In the normal volunteers, the time taken for 50% of inhaled 99mTc DTPA to be cleared from the lungs (T1/2) was 66 minutes±1 sd of 12 mins. The smokers had a mean T1/2 of 20 mins±1 sd 4 min. In the hard-core glue-sniffing group, the majority were smokers who had stopped smoking and glue-sniffing for periods varying from 1 day to 42 days, and it was possible to note the changes in clearance times against period of abstinence. In the patients with inhalation burns, there was change in lung clearance arising from pulmonary epithelial damage; these patients showed increased rate of clearance (short T1/2) with mean T1/2 of 36 min±1 sd of 11 mins, while the retention images revealed regional lung damage in moderately severe inhalation burns. Twenty-four patients with COPD had inhalation scans done with Tc-99m tin colloid radioaerosol, and these images were compared with the perfusion lung scans done with 99mTc macroaggregated albumin (MAA); in general the perfusion images matched the defects noted in the inhalation scans. The 99mTc DTPA clearance rate in these patients was normal i.e. T1/2=78±14 mins. In the thyroid cancer patients with lung metastases, who had high doses of radioiodine treatment, the T1/2 values were normal or prolonged slightly, mean T1/2=76 min±23. (author)

  5. Technetium Tc 99m diphosphonate bone scan. False-normal findings in elderly patients with hematogenous vertebral osteomyelitis

    Hematogenous osteomyelitis is usually diagnosed by an abnormal technetium Tc 99m diphosphonate bone scan in symptomatic patients who have positive blood cultures. False-normal 99mTc bone scans have been described recently in neonates with biopsy-proved osteomyelitis. This phenomenon seems to be extremely rare in adults. Two elderly patients with hematogenous vertebral osteomyelitis had normal technetium Tc 99m diphosphonate bone scans when first evaluated. In both cases the bone scans became abnormal four to six weeks after onset of symptoms and two to four weeks after the initial normal results of the study. When suggested by the clinical picture, hematogenous osteomyelitis cannot be ruled out by a normal 99mTc bone scan at any age. Gallium scan, computed tomographic scan, or bone biopsy can be helpful in such cases

  6. Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children

    Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm2 body surface) in addition to normal oral fluid intake, weight-related dose of 99mTc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as ''normal'' with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinuria and glucosuria), normal renal parenchyma (on ultrasonography, MAG 3 scan and intravenous pyelography), absence of significant obstruction and gross reflux (> grade I) no single kidney and no difference in split renal function > 20%. Results showed increasing MAG 3 clearance values for infants during the first months of life, reaching the normal range for older children and adults between 7 and 12 months. (orig.)

  7. Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children

    Schofer, O. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Koenig, G. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Bartels, U. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Bockisch, A. [Department of Nuclear Medicine, Johannes-Gutenberg University, Mainz (Germany); Piepenburg, R. [Department of Nuclear Medicine, Johannes-Gutenberg University, Mainz (Germany); Beetz, R. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Meyer, G. [Department of Nuclear Medicine, Ludwig Maximilians University, Munich (Germany); Hahn, K. [Department of Nuclear Medicine, Ludwig Maximilians University, Munich (Germany)

    1995-11-01

    Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm{sup 2} body surface) in addition to normal oral fluid intake, weight-related dose of {sup 99m}Tc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as ``normal`` with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinuria and glucosuria), normal renal parenchyma (on ultrasonography, MAG 3 scan and intravenous pyelography), absence of significant obstruction and gross reflux (> grade I) no single kidney and no difference in split renal function > 20%. Results showed increasing MAG 3 clearance values for infants during the first months of life, reaching the normal range for older children and adults between 7 and 12 months. (orig.)

  8. Detection of diaphragmatic disruptions by peritoneoscintigraphy using technetium-99M diethylene-triamine pentacetic acid

    Intraperitoneal injection of a selected radiopharmaceutical results in the diffusion of radioactive material throughout the peritoneum. A diaphragmatic injury should theoretically result in the diffusion of the radioactive material into the chest. To test this hypothesis, Technetium-99m diethylene-triamine pentacetic acid (Tc-99m DTPA) was administered intraperitoneally by either direct needle injection or catheter into 18 rabbits. Four of the rabbits served as controls and did not have any diaphragmatic injury. Fourteen rabbits had surgically induced diaphragmatic tears of varying size (1/4 to 1 cm) after thoracotomy. Four of the 14 rabbits were dropped from the study because they had inadequate peritoneal injections of the radiopharmaceutical. The remaining ten rabbits showed peritoneoscintigraphic evidence of diaphragmatic injury either by showing passage of the radiotracer into the chest, demonstrating the site of injury as a focal region of increased radiotracer uptake, or showing both of these features. Peritoneoscintigraphy appears to be a potentially useful modality in the detection of diaphragmatic injury

  9. A comparative technetium 99m hexamethylpropylene amine oxime SPET study in different types of dementia

    Habert, M.O.; Piketty, M.L.; Askienazy, S. (Centre Hospitalier Sainte-Anne, 75 - Paris (France). Dept. de Medecine Nucleaire); Spampinato, U.; Mas, J.L.; Recondo, J. de; Rondot, P. (Centre Hospitalier Sainte-Anne, 75 - Paris (France). Dept. de Neurologie); Bourdel, M.C. (Centre Hospitalier Sainte-Anne, 75 - Paris (France). Dept. de Psychiatrie)

    1991-01-01

    Regional cerebral perfusion was evaluated by single photon emission tomography (SPET) using technetium 99m hexamethylpropylene amine oxime ({sup 99m}Tc-HMPAO) as a tracer, in 13 control subjects and 44 age-matched patients suffering from dementia of the Alzheimer's type (DAT, n=19) presumed Pick's disease (n=5), idiopathic Parkinson's disease with dementia (DPD, n=15) and progressive supranuclear palsy (PSP, n=5), HMPAO uptake was measured in the superior frontal, inferior frontal, parietal, temporal and occipital cortices, and the perfusion values were expressed as cortical/cerebellar activity ratios. As compared with controls, tracer uptake ratios in the DAT group were signficantly reduced over all cortical regions, with the largest defects in the parieto-temporal and superior frontal cortices. A marked hypoperfusion affecting the superior and inferior frontal cortices was found in Pick's diesease, whereas a mild but significant hypoperfusion was observed only in the superior frontal cortex of patients with PSP. In the DPD group, HMPAO uptake was significantly reduced in the parietal, temporal and occipital cortices, but not in the frontal cortex. These results show that DAT and DPD share the opposite anteroposterior HMPAO uptake defect as compared with the Pick's and PSP groups. (orig.).

  10. A comparative technetium 99m hexamethylpropylene amine oxime SPET study in different types of dementia

    Regional cerebral perfusion was evaluated by single photon emission tomography (SPET) using technetium 99m hexamethylpropylene amine oxime (99mTc-HMPAO) as a tracer, in 13 control subjects and 44 age-matched patients suffering from dementia of the Alzheimer's type (DAT, n=19) presumed Pick's disease (n=5), idiopathic Parkinson's disease with dementia (DPD, n=15) and progressive supranuclear palsy (PSP, n=5), HMPAO uptake was measured in the superior frontal, inferior frontal, parietal, temporal and occipital cortices, and the perfusion values were expressed as cortical/cerebellar activity ratios. As compared with controls, tracer uptake ratios in the DAT group were signficantly reduced over all cortical regions, with the largest defects in the parieto-temporal and superior frontal cortices. A marked hypoperfusion affecting the superior and inferior frontal cortices was found in Pick's diesease, whereas a mild but significant hypoperfusion was observed only in the superior frontal cortex of patients with PSP. In the DPD group, HMPAO uptake was significantly reduced in the parietal, temporal and occipital cortices, but not in the frontal cortex. These results show that DAT and DPD share the opposite anteroposterior HMPAO uptake defect as compared with the Pick's and PSP groups. (orig.)

  11. Contribution to optimization of individual doses of workers in shipment of generator technetium-99m

    The Instituto de Pesquisas Energeticas e Nucleares, IPEN, radiopharmaceuticals research and produce that are distributed throughout Brazil, currently the radiopharmaceutical with the largest number of packaged shipped per year and with the highest total activity is the 99m technetium generator. To reduce individual doses for workers involved in the production of radiopharmaceuticals was performed a study of radiological protection optimization in the shipment process of technetium generator, using the techniques: differential cost-benefit analysis, integral cost-benefit analysis, multi-attribute utility analysis and multi-criteria outranking analysis. With changes in the configuration of packed for generator dispatch and with the acquirement of a mat transporter it was possible establish 4 protection options. The attributes considered were the protection cost, collective dose, individual dose and physical effort by worker to move the package without the mat. To assess the robustness of analytical solutions found with the techniques used in the optimization we performed a sensitivity study and found that option 3 is more robust than option 1, which is no longer the analytical solution with an increase of R$ 20.000,00 the cost of protection. (author)

  12. Technetium 99 m spiperone dithiocarbamate study as a potential agent for brain pathologies diagnosis related to D 2 dopamine receptors

    Psycho-pharmacology has been discovering much about the D 2 dopamine receptors and their interrelationship to brain pathologies such as Parkinson's Disease, Schizophrenia and Huntington Disease. Those biological receptors have got affinity with dopamine endogenous agent, so that they complex and, in non pathological individuals, the biological receptors contribute to bring the levels of dopamine and free acetylcholine into equilibrium. The D 2 antagonistic psychotropic agents because of having got strong affinity with those receptors, have been being transformed into radiopharmaceuticals to diagnose these pathological disease of Central Nervous System. The Spiperone Dithiocarbamate complex studied by us, is a potential diagnosis agent because of being highly lipo-soluble and having close relationship with D 2 receptors. Besides, it is a photon emitter, allowing the use of SPECT (Single Photon Emission Computed Tomography) technique which is economically less expensive if compared to the PET (Positron Emission Tomography) technique. The Spiperone Dithiocarbamate (SPDC) is synthesized from Spiperone and its complexation with Technetium-99 m has been prepared with its reaction parameters after being studied and improved. The SPDC-99m Tc complex biological distribution have made in Wistar rats and the uptake of spleen, heart, liver stomach, lung, kidney, blood, intestine and brain have been resolved. The plasmatic clearance curve has been based on Wistar rats data and the know-how of the kit (for label SPDC with Tc) has been achieved. (author). 5 figs, 4 tabs

  13. Technetium 99m pyrophosphate bone scintigraphy in the exploration of breast cancer bone metastases (analysis of 311 examinations)

    Sodium pyrophosphate was chosen for its ease of application and the quality of the images it gives. The aim of this study, in the context of breast cancer exploration, is to examine: - its reliability for the detection of bone metastases, - the correlation of its results with other factors. The first part reviews the properties of sup(99m)Tc-labelled sodium pyrophosphate and the current hypotheses on the mechanism of its bone fixation, essential for an understanding of the image formation mechanism and for the interpretation of anomalies. Part two gives an analysis of 311 examinations carried out on 223 patients, obtained by the use of a coded file and modern data processing methods. The following are dealt with in turn: - material and methods, - the results themselves and especially their reliability for the whole skeleton and for one bone at a time, - discussion and comparison with published data. Sup(99m)Tc pyrophosphate bone scintigraphy is a simple examination easy to interpret and allows the whole skeleton to be explored. Abnormal scintigraphic images are: - seldom hypofixing lacunae, - usually 'hyperfixing centres' which point to a perilesional bone reaction and depend on: vascular factors, the affinity of technetium for the immature collagen fibres of the forming bone matrix, the affinity of pyrophosphate for the bone mineral substance

  14. Initial investigations of 99mTc-labeled morpholinos for radiopharmaceutical applications

    This laboratory is evaluating phosphorothioate deoxyribonucleic acids (DNAs) and peptide nucleic acids (PNAs) for a variety of nuclear medicine applications. Morpholinos (MORFs) are a new class of oligomers with a nuclease-resistant, nonionic and water-soluble phosphorodiamidate backbone. We now report on the in vitro and in vivo properties of MORFs labeled with technetium-99m. Both 15-mer and 18-mer MORFs were obtained, each with a primary amine attached to the 3' equivalent end via a three-carbon beta-alanine linker. The amine was used to conjugate with NHS-MAG3 for 99mTc radiolabeling. By surface plasmon resonance at room temperature, the association rate constant for hybridization of the 18-mer MORF to its complementary oligomer (cMORF) was equivalent to that of DNAs and PNAs of comparable length. Hybridization of 99mTc-MORF in vitro to free cMORF, to a cMORF polymer and to cMORF beads was nearly quantitative under a variety of conditions. Kinetic studies in vitro at room temperature showed rapid (2-5 min) and nearly quantitative (90%) binding to cMORF beads. Using size-exclusion high-performance liquid chromatography, the stability of the 99mTc-MORF was found to be greater than 85% over 24 h in 37 C serum with minimal protein binding. In normal mice, the 99mTc-MORF showed rapid pharmacokinetics, with only 21% and 8% remaining in the whole body at 3 and 24 h post administration, respectively. In vivo targeting with 99mTc-MORF of cMORF beads in one thigh of normal mice compared to control beads in the other thigh showed target/control thigh ratios of 2-10 between 3 and 24 h. These results demonstrate that MORF oligomers are capable of in vivo hybridization. Their properties of hybridization affinity and kinetics and their in vivo stability and pharmacokinetics make them suitable subjects for in vivo studies. (orig.)

  15. Radiolabelling of poly(butyl 2-cyanoacrylate) nanoparticles with a technetium-99m-dextran complex

    Poly(butyl 2-cyanoacrylate) nanoparticles have been radiolabelled with a sup(99m)Tc-dextran complex to allow their pattern of biodistribution to be followed by using the technique of gamma scintigraphy. The method involves the performing of a sup(99m)Tc-dextran complex and using this as a polymeric stabiliser during the formation of nanoparticles. Copolymerisation of this complex with the cyanoacrylate monomer results in the radiolabel being covalently linked to the nanoparticle matrix with a labelling efficiency of approximately 18%. The radiolabelled nanoparticles slowly degrade and release the activity into buffer solution. The release rate was relatively unaffected by the presence of plasma proteins indicating that the system should be suitable for use in vivo. (author)

  16. Technetium-99m spiperone dithiocarbamate: a potential radiopharmaceutical for dopamine receptor imaging with SPECT

    Spiperone dithiocarbamate (SPDC) was prepared by reacting spiperone with carbon disulfide followed by sodium hydroxide. SPDC was labelled with 99mTc by reduction of pertechnetate with formamidine sulfinic acid or sodium pertechnetate with formamidine sulfinic acid or sodium dithionite at alkaline pH, resulting in ∼ 40% incorporation of 99mTc. The lipophilic complex was conveniently isolated at high specific activity and high radiochemical purity by extraction into dichloromethane, which was then evaporated and the residue was redissolved in a 1:3 mixture of ethanol and saline containing 0.1mg/ml gentisic acid. Biodistribution studies following i.p. injection in rats showed low uptake of radioactivity in the brain, but striatum/cortex and striatum/cerebellum ratios were reduced by pretreatment with haloperidol. This agent may allow imaging of dopamine D-2 receptors using single-photon emission computed tomography (SPECT). (author)

  17. Effect of passiflora quadrangularis extracts on the technetium-99m biodistribution in mice; Efeito de extratos do maracuja-acu na biodistribuicao do tecnecio-99m em camundongos

    Bezerra, A.L.; Souza, G.M.L.; Nascimento, E.V.; Carvalho, E.B.; Catanho, M.T.J.A. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica] E-mail: mariajansem@hotmail.com

    2002-07-01

    Medicinal plants have been evaluated and their effect on the biodistribution of radiopharmaceuticals are very important. This work aims to evaluate the interaction of extracts of Passiflora quadrangularis on the biodistribution of {sup 99m}Tc in mice (Mus musculus). The animals were submitted to brief treatment with aqueous (G1) and hydroalcoholic 10% (G2) extracts. Control animals received saline solution 0.9% (n=5). The reaction {sup 99m}Tc (3.7 MBq) in the presence of stannous chloride and extracts was incubated for 10 minute, then it was injected (ip way) in mice. At the end of 30 minutes, animals were sacrificed for removal of organs and 0.5 mL of blood, which were counted in gamma counter. The percentage of {sup 99m}Tc-binding was calculated in relation to the weight of each organ. The results show a reduction on right and left kidneys in the presence of aqueous extract at about 26.74%, and more significant reduction in the presence of hydroalcoholic 10% extract at about 72.81%. the trachea presents a binding capacity to {sup 99m}Tc in order of 263.5% in the presence of aqueous extract. These results demonstrate that {sup 99m}Tc presents affinity to some organs and that the extract of Passiflora quadrangularis is able to alter this labeling. Therefore, more attention has been given to diagnoses with pharmaceutical compounds labeled with radioisotopes. (author)

  18. Quantitative scanning using gallium-67 citrate and technetium-99m pyrophosphate in 51 total hip prosthesis reoperations

    In case of painful hip prosthesis, it is essential to detect evidence of infection on order to decide reoperation and its methods. A quantitative scanning using both gallium-67 (67Ga) and technetium-99m pyrophosphate (sup(99m)Tc-PP) was performed in 49 patients who afterwards underwent revision surgery with bacteriological examinations. 67Ga scanning has proven to be a method particularly more sensitive, specific and reliable than the one using sup(99m)Tc-PP, providing that patients previously treated by antibiotics are excluded. So, 67Ga scanning seems to be essential before any antibiotic treatment, in case of painful prosthetic hip, when infection is suspected

  19. Labelling of m-trimethyl silylphenyl-ethylidene-1, i-bisphosphonate with /sup 99m/Tc and its evaluation as an imaging agent

    Technetium-99m labeled phosphates and phosphonates have since long been in use for bone imaging to diagnose bone infection, bone metastasis and bone fracture. /sup 131/ I -labeled bisphosphonates have also been prepared for targeted radiotherapy of bone metastasis. Although animal experiments show good accumulation of bisphosphonates in bone. The agent has never been tried in humans because of high gamma and beta energy. The agent must first be tested in humans using a relatively safe radioisotope. Technitium-99m (/sup 99m/Tc) a radioisotope with relatively low gamma energy 99m and short half-life can serve as a good label. Whether /sup 99m/Tc-labeled bisphosphonates can be used as good imaging agents is another aspect that needs further investigation. A study was therefore, conducted to label m-trimethyl silylphenyl)-ethylidene-1, 1-bisphosphonate with /sup 99m/Tc and standardize the labeling procedure. The labeling procedure - involved reduction of technetium (TcO/sub 4/) with stannous chloride followed by chelation of technetium with bisphosphonates. Radiochemical purity was checked by paper chromatography. Pyrogenicity was checked by administration of the labeled compound into rabbits. The stability of the compound was determined by noting the radiochemical binding at several intervals of half an hour after preparation. Biodistribution of the agent was studied by injecting the labeled compound into rabbits. The results showed that the compound could be labeled with /sup 99m/Tc without any difficulty. The ease of binding was excellent. There was more than 95% binding of technetium with the compound and the labelled compound was reasonably stable for 5 hours after labeling. The rectal temperature remained stable during this period, which showed that the animal accepted the compound and there were no pyrogenic reactions. Biodistribution studies on rabbit showed that accumulation of agent was poor in bones and the labeled compound remains in blood even after 4

  20. sup(99m)Tc-labelled Cu(I)-EHDP, a potential skeletal imaging agent

    sup(99m)Tc-Cu-EHDP has been prepared with high labelling yield applying for the first time the method of instantly formed cuprous ions in the mixture. A gelchromatography column scanning technique has been to study the sup(99m)Tc fractions in the preparation. The study of the influence of pH-value on the amount of sup(99m)Tc-Cu-EHDP fraction shows that pH 1.6-1.7 gave the best labelling results. The formation rate of sup(99m)Tc-Cu-EHDP complex with a high labelling yield was fast and achieved within a few mins. This suggests the reduction of sup(99m)Tc-pertechnetate to Tc (IV). The final preparation was found stable for at least 4 hrs after mixing the reactants with the sup(99m)Tc-eluate. Comparative biokinetic studies of sup(99m)Tc-Cu-EHDP and sup(99m)Tc-Sn-EHDP in rabbits and mice showed a high bone uptake and fast elimination of sup(99m)Tc-Cu-EHDP from the skeleton. No significant difference was found in the plasma protein binding of sup(99m)Tc-Cu-EHDP and sup(99m)Tc-Sn-EHDP in rats as assessed by the GCS-technique. Radionuclide imaging in rabbits, using a gamma camera, showed sup(99m)Tc-Cu-EHDP to be a good bone-imaging agent. (orig.)

  1. Identification of Staphylococcus aureus infection by aptamers directly radiolabeled with technetium-99m

    Introduction: Aptamers are oligonucleotides that have high affinity and specificity for their molecular targets which are emerging as a new class of molecules for radiopharmaceuticals development. In this study, aptamers selected to Staphylococcus aureus were evaluated for bacterial infection identification. Methods: Anti S. aureus aptamers were labeled with 99mTc by the direct method. The radiolabel yield and complex stability were assessed by thin-layer chromatography (TLC). Three groups of Swiss mice containing 6 animals each were used. The first group was infected intramuscularly in the right thigh with S. aureus. The second group was infected in the same way with C. albicans and the third group was injected with zymosan to induce aseptic inflammation. After 24 h, radiolabeled aptamers (22.2 MBq) were injected by the tail vein. The mice were euthanized 4 h post injection and tissue sample activities measured in a gamma counter. Results: The 99mTc labeled aptamers were stable in saline, plasma and cystein excess. Radiolabeled aptamers showed increased uptake in the kidneys for all groups indicating a main renal excretion, which is consistent with the hydrophilic nature and small size of aptamers. The radiopharmaceutical showed rapid blood clearance indicated by a reduced dose (% ID/g) in the blood. The biodistribution showed that aptamers were able to identify the infection foci caused by S. aureus displaying a target/non-target ratio of 4.0 ± 0.5. This ratio for mice infected with C. albicans was 2.0 ± 0.4 while for mice with aseptic inflammation was 1.2 ± 0.2. Histology confirmed the presence of infection in groups 1 and 2, and inflammation in group 3. Conclusions: The biodistibution study demonstrated a statistically higher uptake in the S. aureus foci relative to inflammation and C. albicans infected areas. These results highlight the potential of aptamers labeled directly with 99mTc for bacterial infection diagnosis by scintigraphy

  2. The effects of {sup 99m}Tc-HMPAO-labelled leucocyte scan on human karyotype

    Liberatore, Mauro; Prosperi, Daniela; Iurilli, Anna Paola [Section of Nuclear Medicine, Department of Experimental Medicine and Pathology, University of Rome ' ' La Sapienza' ' , Policlinico Umberto I, Viale Regina Elena 324, 00161, Rome (Italy); Poscente, Monica; Mancini, Barbara; Grammatico, Paola [Medical Genetics, Department of Experimental Medicine and Pathology Department, University of Rome ' ' La Sapienza' ' , Rome (Italy); Donnetti, Massimo [Section of Medical Physics, Department of Experimental Medicine and Pathology, University of Rome ' ' La Sapienza' ' , Rome (Italy)

    2003-10-01

    Technetium-99m hexamethylpropylene amine oxime (HMPAO) white blood cell scan (WBCS) requires separation and labelling of mixed leucocytes, which include particularly radiosensitive cells, lymphocytes. Lymphocytes labelled during the mixed leucocyte labelling procedure could represent a problem for patients owing to the possible induction of chromosomal aberrations. Lymphocytes labelled in mixed leucocyte preparations are probably killed by the high-dose radiation. Nevertheless, it has been reported that some of these lymphocytes can proliferate after in vitro stimulation. If these cells were to reproduce themselves in vivo, onset of, or increase over time in, chromosomal aberrations could occur on peripheral blood lymphocytes. The present study was performed on 21 patients who underwent WBCS for suspected infection/inflammation. Blood samples of these patients were submitted to cytogenetic study, comprising karyotype determination, evaluation of sister chromatid exchanges (SCE) and evaluation of induced chromosomal breakages or rearrangement rate (B/R). This study was performed 2 h before and 7 days and 6 months after the WBCS. The results demonstrated no statistically significant differences between SCE and B/R values before and after WBCS. No cause-effect relationship appeared to exist between WBCS and the onset of chromosomal aberrations in peripheral blood lymphocytes, at least during the first 6 months post WBCS and within the limits of this study's approach. The high-dose radiation administered to lymphocytes was almost certainly sufficient to kill these cells. (orig.)

  3. Tracing of erythrocytes in vitro with technetium-99 m: clinical applications

    The human beings' erythrocytes were studied in vitro by the pre tinning method, using the pyrophosphate - Stannous Chloride Kit. Investigation of factors that can alter the labeling efficiency includes tin concentration, temperature and incubation period, besides of plasma concentration and hematocrit. It was seen that tin uptake by the red blood cells (RBC) was in an exponential fashion, with a reaction constant, K = 0,03 min -1. The reaction approaches the equilibrium about the 90 minutes. The binding of Tc-99 m in the Acidic insoluble fraction occurs in greater amounts with more concentrated tin solutions. The labeled and heated TBC were used in vivo to scintigraphic investigation. Normal subjects, splenomegaly, accessory spleen and splenic function in sickel-cell disease were studied. Circulation time of labeled RBC appears to be greater in sickel-cell anemia than in controls or splenectomized patients. Uptake was greater in kidney than lungs and liver. (author)

  4. Simple differential functional study of the kidney using sup(99m) technetium DMSA

    A simple technique has been developed to study the differential kidney function. It involves the intravenous injection of a product labelled with sup(99m)Tc, which possesses in vivo the characteristics of organo-mercurial derivatives. High-resolution kidney images are obtained, eliminating the excretion component which may be obtained with DTPA type products studying the glomerular filtration. The absolute quantitative uptake and the left kidney to right kidney activity ratio were measured successfully. This technique should find an increasing application in the evaluation of patients suffering from various kidney disorders including hypertension and acute pyelonephritis

  5. Comparison study among methodologies of planar chromatography for radiochemical control of technetium-99m; Estudo comparativo entre metodologias de cromatografia planar para controle radioquimico de radiofarmacos de tecnecio-99m

    Monteiro, Elisiane de Godoy

    2012-07-01

    Radiopharmaceuticals are substances that have radioisotopes in their composition. About 95% of the procedures performed in nuclear medicine use radiopharmaceuticals with diagnostic purposes, and the Lyophilized Reagents (LR) labeled with Technetium-99m ({sup 99}mTc), obtained from {sup 99}Mo/{sup 99}mTc generator, are the most one used. Quality Control represents the set of assays to be performed to assure that the product is adequate to its purpose. An important feature to be evaluated in {sup 99m}Tc radiopharmaceuticals is the radiochemical purity (% RqP) to quantify free pertechnetate ({sup 99}mTcO{sub 4}{sup -}) and technetium colloidal (99mTcO{sub 2}) mainly by paper chromatography (PC), thin layer (TLC) and High Performance Liquid Chromatography (HPLC). The objective of this work was to perform the comparison among the radiochemical control methodologies of LR labeled with {sup 99m}Tc, described in the United States Pharmacopoeia (USP) and European Pharmacopoeia (EP) and those used by IPEN. {sup 99m}TcO{sub 4}{sup -} eluate and DISIDA, DMSA, DTPA, EC, ECD, GHA, MIBI, MDP, PIRO, SAH and Sn Coloidal LR were provided by IPEN-CNEN/SP. TLC-cellulose, TLC-SG.TLC-SG reverse phase, HPTLC-cellulose, HPTLC-SG (Merck) and ITLC-SG (Pall Corporation), W1MM, W3MM, W17M e W31ET (Whatman) chromatographic plates were used. The measurement of the radioactivity was done in a Perkin Elmer Cobra D-5002 gamma counter. LR were labeled to obtain 55,0 MBq mL{sup 1} (1,5 mCi mL{sup 1}) of final radioactive concentration. The %{sup 99m}TcO{sub 4}{sup -}, %{sup 99m}TcO{sub 2} and % RqP were determined up to 4 hour labeling. From 11 LR, only EC and GHA have no radiochemical control methods in USP and EP. In USP and/or EP, DTPA, MDP, PIRO, SAH and Sn Coloidal methods use ITLC-SG; IPEN uses this chromatography plate in DISIDA, EC, ECD, GHA, PIRO, MIBI and SAH. As ITLC-SG had been out of production (recommended in 40, 70 and 41% of the USP, EP and IPEN methodologies, respectively), it was

  6. Synthesis of new monosubstituted methanediphosphonic acids and in vivo study in animals of their metal complexes with technetium 99m

    A new class of monosubstituted methanediphosphonic acids has been synthesized and their acidic constants were determined by potentiometry. Metal complexes with technetium 99m have been prepared and analysed by paper chromatography. In vivo study of their behaviour has been tested on to the animal. These compounds, inorganic pyrophosphate analogues, are potential bone seeking agents

  7. Technetium-99m colloidal bismuth subcitrate: A novel method for the evaluation of peptic ulcer disease

    The therapeutic agent colloidal bismuth subcitrate (CBS) selectively binds to peptic ulcers. The authors have developed a method for labeling this agent with Tc-99m. Chromatographic quality control studies of the agent on silica gel coated strips (ITLC-SG) showed that more than 97% of Tc-99m was bound to CBS. During in-vitro stability testing, the radio-label was stable for a minimum of 6 hours. The chromatographic findings are in agreement with the in-vivo distribution of the agent which showed no significant radioactivity in thyroid, kidneys, liver, or bladder. The resulting Tc-99m-CBS solution is administered orally in drinking water. Preliminary animal studies have been conducted on 5 adult 3 kg New Zealand rabbits sedated with 50 mg Ketamine I.M. The rabbits were intubated with I.V. tubing advanced to the stomach. They were given a gastric erosive suspension of 600-1000 mg/kg of pulverized ASA in 10 cc tap water. Four hours later they were given 3-4 mCi of the radiotracer in a 5 cc volume of water. Serial in-vivo images were obtained for 2 hours which included thyroid, abdomen, and urinary bladder. Next the stomachs were excised, opened along the greater curvature, imaged, vigorously washed and reimaged. All 5 rabbits showed avid localized binding of radiotracer which remained fixed even with vigorous washing. Areas of normal appearing mucosa were relatively devoid of radiotracer. This new compound may have significant clinical usefulness in the detection of peptic ulcer disease. In addition, such a non-invasive technique, carrying none of the risks or discomfort of endoscopy could also find application in the evaluation of the response to therapy

  8. Prognostic value of normal myocardial perfusion images using technetium-99m based compounds

    Full text: The prognostic value of 201Tl myocardial perfusion imaging is well established. The purpose of this study was to describe the clinical outcome of patients with known or suspected ischemic heart disease and a normal myocardial perfusion scan using 99mTc labelled agents (Sestamibi/Tetrofosmin). Fifty-three patients (29 males, 24 females, mean age 51.58 years) with known or suspected coronary artery disease (CAD) were stressed (3 with dipyridamole and 50 with bicycle ergometer) and gated SPECT myocardial perfusion scan obtained with triple head gamma camera. All patients had normal myocardial perfusion and wall motion. Patients were followed up for 21-24 months and follow up data was obtained from telephone interview. Cardiac events were defined as, hard events (myocardial infarct, unstable angina, death) or soft events (angioplasty or other revascularization). ST segment depression occurred in 11 (20.75%), 6 (11.32%) had pre-test angiographically significant CAD, 4 (7.55%) were studied post CABG and 3 (5.6%) patients had a normal post scan angiography. Cardiac events occurred in none of the patients. Our study confirms the benign outcome of patients with normal myocardial perfusion scan using 99mTc labelled agents, even in patients with angiographically significant CAD, consistent with prior observation for 201Tl cardiac imaging. The lesser number of patients who underwent coronary angiography following a normal perfusion scan shows the determination by treating physicians, that no further evaluation was necessary

  9. Role of technetium-99m planar bone scanning in the evaluation of low back pain

    The records of 1018 patients with low back pain in a tertiary spine referral practice were reviewed. One hundred thirty-nine out of 1018 (13.6%) underwent technetium-99m planar bone scannings as part of their investigation. Seventy-three out of 139 scans (52%) showed increased uptake in some area, but only 27 out of 139 (19.4%) showed increased uptake specifically in the low back. Scans consistently yielded no findings with reference to the back when the prescan diagnosis was spinal stenosis, lumbar pain syndrome, herniated nucleus pulposus, or postlaminectomy syndrome. Some scans gave positive findings in patients with a diagnosis of degenerative disc disease, pseudoarthrosis, spondylolisthesis, fracture, infection, metabolic disorder, or tumor. Positive scans were generally obtained early after presentation (within 3 months) and negative scans obtained later (after 6 months), suggesting that clinical suspicion is still the main indication for early scanning. Planar bone scanning was helpful in both diagnosis and therapeutic decision-making in many conditions. (orig.)

  10. Study of immediate technetium 99m uptake by intracranial meningiomas and meningoblastomas

    The immediate uptake of technetium 99m in 43 meningiomas and meningoblastomas, observed with a scintillation camera, was analysed. The study concerns the first 30 seconds of the scintigraphic examination, a period corresponding to the arrival of the tracer in the carotids and its progress in the brain circulation (arterial time, capillary time and venous time). The principle of the examination and the facilities of use of the tracer employed are described, after which the examination procedure and the normal images obtained are reported. The technique applied to these 43 patients revealed an instant uptake site in 37 cases, i.e. about 65%. Of the 6 remaining cases 2 were meningiomas of the posterior cranial fossa, 1 was due to technical mistakes, another corresponded to a cystic meningioma of the convexity and the last two to meningiomas of the small splenoid wing. These results confirm those of other authors. Other immediate uptake centres are provided by angiomas, arteriovenous anevrisms and certain glioblastomas. This sign although very important for the meningioma diagnosis, must be corroborated by results of other examinations. It would be useful to make a kinematic study of instant uptake in order to establish, if possible, the exact time of appearance (arterial, capillary or veinous) of this site in meningiomas and in other tumours where the some clinical sign is observed

  11. Evaluation of brain tumor using technetium-99m-tetrofosmin SPECT. Initial experience

    Technetium-99m-Tetrofosmin (TF) is the tracer for single photon emission computed tomography (SPECT). It is commercially available in Japan and covered by Japanese health insurance only for ischemic heart diseases. In other countries, TF has been used for imaging of various brain tumors. We examined TF SPECT in patients with brain tumor and compared the image findings with other radiological image findings. The study population included 11 patients (4 men and 7 women) aged 48-87 years. The histological tumor diagnoses were as follows: glioblastoma multiforme (GBM; n=7), anaplastic oligoastrocytoma (n=1), meningioma (n=1), and metastasis (n=2). SPECT images were acquired using multidetector SPECT camera (E.CAM, Siemens) at 15 min and 3 h after intravenous injection of 740MBq of TF or 74MBq of Thallium chloride (Tl). The tracer uptakes of TF and Tl were almost similar. Both TF and Tl delayed SPECT images showed hot uptake in the tumors of GBM patients. In meningioma patients, both TF and Tl early images showed hot uptake, whereas the tracers were washed out in delayed images. TF SPECT images were clearer than Tl SPECT images. There was physiological uptake of TF in the normal choroid plexus; this finding helps in understanding the spatial correlation between the tumors and ventricles. No side effects with TF injection were observed. TF SPECT is better and more useful than Tl SPECT to diagnose location, extent, malignancy, and viability of tumors as well as the effects of anticancer therapies. (author)

  12. Role of technetium-99m planar bone scanning in the evaluation of low back pain

    Valdez, D.C. [Texas Univ., San Antonio, TX (United States). Health Science Center]|[St. Luke`s Lutheran Hospital, San Antonio, TX (United States); Johnson, R.G. [Texas Univ., San Antonio, TX (United States). Health Science Center]|[St. Luke`s Lutheran Hospital, San Antonio, TX (United States)

    1994-02-01

    The records of 1018 patients with low back pain in a tertiary spine referral practice were reviewed. One hundred thirty-nine out of 1018 (13.6%) underwent technetium-99m planar bone scannings as part of their investigation. Seventy-three out of 139 scans (52%) showed increased uptake in some area, but only 27 out of 139 (19.4%) showed increased uptake specifically in the low back. Scans consistently yielded no findings with reference to the back when the prescan diagnosis was spinal stenosis, lumbar pain syndrome, herniated nucleus pulposus, or postlaminectomy syndrome. Some scans gave positive findings in patients with a diagnosis of degenerative disc disease, pseudoarthrosis, spondylolisthesis, fracture, infection, metabolic disorder, or tumor. Positive scans were generally obtained early after presentation (within 3 months) and negative scans obtained later (after 6 months), suggesting that clinical suspicion is still the main indication for early scanning. Planar bone scanning was helpful in both diagnosis and therapeutic decision-making in many conditions. (orig.)

  13. Clinical estimation of acute myocardial infarct size with /sup 99m/technetium pyrophosphate scintigraphy

    We evaluated scintigraphic techniques in estimating infarct size. In 26 patients with acute transmural myocardial infarction, /sup 99m/Technetium pyrophosphate (TcPYP) infarct scintigraphy, gated cardiac blood pool scintigraphy and 201-Thallium (201-Tl) perfusion scintigraphy were performed. Invasive hemodynamic measurements were obtained and serial venous blood specimens taken for measurement of total and MB creatine phosphokinase (CPK). Infarct size was estimated from the area of abnormal TcPYP uptake, the extent of reduced 101-Tl uptake, the percentage of abnormally contracting segments, and serial enzyme measurements. Left ventricular ejection fraction (LVEF) and stroke work index (LVSWI) were calculated. TcPYP infarct area was associated with the extent of reduced 201-Tl uptake (r = 0.66), the percentage of abnormally contracting segments (r = 0.64), and with both LVSWI (r = 0.73) and LVEF (r = -0.58). TcPYP infarct area did not correlate with cumulative total or MB-CPK release or the integrated total CPK-time curve, nor did the enzyme estimates of infarct size correlate with LVSWI or LVEF. Variable perfusion of infarcts of different sizes may explain the lack of correlation between TcPYP infarct area and enzyme estimates of infarct size. A combination of anatomic and functional indices derived from scintigraphic and hemodynamic measurements may provide the best assessment of infarct size

  14. Analysis of 99mTc-labeled radiopharmaceuticals by high-performance liquid chromatography

    High-performance liquid chromatography (HPLC) equiped with on line radiometric and optical detectors (i.e. radio-HPLC) have been applied to the radiochemical analysis of commonly-used 99mTc-radio pharma ceuticals with a view point to check the radiochemical purities of the compounds. Chromatographic conditions were determined by examination of the types of column, mobile phase and pH. An aqueous size-exclusion (Shim-pack Diol-300) and reversed-phase column (Zorbax-ODS) were found to be suitable for 99mTc-HSA and the other 99mTc-agents, respectively. The analysis of low molecular weight 99mTc-agents (e.g. 99mTc-DTPA, 99mTc-DMSA, 99mTc-pyrophosphate, 99mTc-phytic acid, 99mTc-MDS, 99mTc-HMDP) were done by reversed-phaseion pairing chromatography using a optimized mobile phase consisted on a mixture of 50 mM phosphate buffer (pH 7.0) and 2 mM TBA (tetra nbutyl) ammonium hydroxide) in 30 % methanol. The mobile phases for analysis of medium molecular weight 99mTc-HSA were consisted of a mixture of 50 mM phosphate buffer (ph 7.0) in 30 % methanol, and a mixtures of 1 % SDS (sodium dodecyl sulfonate) in Tris buffer (pH. 7.0), respectively. It was apparent from the radio-chromatograms obtained from these chromatographic conditions, that impurity of 99mTcO4 was observed in 99mTc-pyrophosphate, 99mTc-phytic acid, 99mTc-MDP, 99mTc-HMDP, and impurities of 99mTc-labeled species and 99mTcO4, were observed in 99mTc-HIDA, 99mTc-HIDA, 99mTc-HSA. The radiochemical impurities of the 99mTc-radiopharmaceuticals were ranged between 90 and 100 %. From these results, radio-HPLC has been shown to be suitable method for analysis of 99mTc-radiopharmaceuticals, with rapidity and excellent precision. (author)

  15. Preparation of Human Serum Albumin Macroaggregated (MAA) labelled with 99mTc via Ligand Exchange

    An alternative method for the preparation of human serum albumin macroaggregated (MAA) labelled with 99mTc for lung scanning is described. The method is based on the use of stannous methylene diphosphonate (Sn-MDP) as a reducing agent. The may be also increase the number of binding sites in the MAA. The different parameters affecting the labelling yield and in-vitro stability of 99mTc-MAA have been studied in order to determine the optimum conditions for labelling macroaggregated with 99mTc. A high labelling yield (98.9%) was achieved and more than 98% of 99mTc-MAA coated with Sn-MDP. The determined lung uptake in mice was found to be ≥ 90% which better than the reported data. A particular procedure compared to the existing reported procedures, which is recommended for the preparation of Sn-MDP coated MAA labelled with 99mTc for lung perfusion imaging

  16. Tc-99m-labeled Rituximab for Imaging B Lymphocyte Infiltration in Inflammatory Autoimmune Disease Patients

    Malviya, G.; Anzola, K. L.; Podesta, E.; Lagana, B.; Del Mastro, C.; Dierckx, R. A.; Scopinaro, F.; Signore, A.

    2012-01-01

    The rationale of the present study was to radiolabel rituximab with 99m-technetium and to image B lymphocytes infiltration in the affected tissues of patients with chronic inflammatory autoimmune diseases, in particular, the candidates to be treated with unlabelled rituximab, in order to provide a r

  17. The rabbit biodistribution of a therapeutic dose of zoledronic acid labeled with Tc-99m

    Asikoglu, Makbule [Ege University, Faculty of Pharmacy, Department of Radiopharmacy, Bornova 35100, Izmir (Turkey)], E-mail: makbule.asikoglu@ege.edu.tr; Gamze Durak, Funda [Ege University, Faculty of Pharmacy, Department of Radiopharmacy, Bornova 35100, Izmir (Turkey)

    2009-09-15

    The aim of the present study was to label a therapeutic dose of zoledronic acid (ZOL) with Tc-99m, evaluate its in vitro stability and compare its biodistribution to {sup 99m}Tc-methylene biphosphonate ({sup 99m}Tc-MDP) in normal rabbits. Preparation of 0.50 mg of {sup 99m}Tc-ZOL was carried out by the reduction of {sup 99m}Tc-pertechnetate in the presence of stannous chloride. The radiolabeling efficiency was found to be greater than 99%. The labeled complex was stable at least up to 6 h at room temperature determined by paper chromatography. {sup 99m}Tc-ZOL and {sup 99m}Tc-MDP were administered intravenously to the rabbits for scintigraphic studies. Between {sup 99m}Tc-ZOL and {sup 99m}Tc-MDP, there were no significant differences in the ratios of femur/BG and lumbar vertebrae/BG, whereas epiphysis/BG and the kidney/BG ratios of {sup 99m}Tc-MDP were higher than {sup 99m}Tc-ZOL at the static studies.

  18. Evaluation of Deoxyribonucleic Acid Toxicity Induced by the Radiopharmaceutical 99mTechnetium-Methylenediphosphonic Acid and by Stannous Chloride in Wistar Rats

    Adriano Caldeira-de-Araujo

    2012-11-01

    Full Text Available Radiopharmaceuticals are employed in patient diagnostics and disease treatments. Concerning the diagnosis aspect, technetium-99m (99mTc is utilized to label radiopharmaceuticals for single photon computed emission tomography (SPECT due to its physical and chemical characteristics. 99mTc fixation on pharmaceuticals depends on a reducing agent, stannous chloride (SnCl2 being the most widely-utilized. The genotoxic, clastogenic and anegenic properties of the 99mTc-MDP(methylene diphosphonate used for bone SPECT and SnCl2 were evaluated in Wistar rat blood cells using the Comet assay and micronucleus test. The experimental approach was to endovenously administer NaCl 0.9% (negative control, cyclophosphamide 50 mg/kg b.w. (positive control, SnCl2 500 μg/mL or 99mTc-MDP to animals and blood samples taken immediately before the injection, 3, and 24 h after (in the Comet assay and 36 h after, for micronucleus test. The data showed that both SnCl2 and 99mTc-MDP-induced deoxyribonucleic acid (DNA strand breaks in rat total blood cells, suggesting genotoxic potential. The 99mTc-MDP was not able to induce a significant DNA strand breaks increase in in vivo assays. Taken together, the data presented here points to the formation of a complex between SnCl2 in the radiopharmaceutical 99mTc-MDP, responsible for the decrease in cell damage, compared to both isolated chemical agents. These findings are important for the practice of nuclear medicine.

  19. Preparation of an ultra high pure technetium-99m pentavalent dimercaptosuccinic acid (Tc99m(V) DMSA) and evaluation of kinetics

    Full text: Tc-99m (V) DMSA as a clinically useful tumour-seeking agent is widely reported and its preparation was first described by simply adding NaHCO3 to commercially available renal agent kit, DMSA (m), and raising the pH to 8.5. Later methods used oxygen bubbling to improve the purity of Tc-99m (V) DMSA. However, the percentage purity of the product was not consistent, varying between 83 and 94% (Kobayashi H, Eur J Nucl Med 1995:22,559-562). The present study was undertaken with a view to improve the purity of the preparation and evaluate the kinetics. Stannous ions play a central role in Tc-99m labelled compounds in general, particularly so with the preparation of Tc-99m(V)DMSA from the trivalent precursor. To resolve the issue of whether the excess stannous ions must be oxidised to ensure no further reduction of the pentavalent product back to its trivalent form, we prepared two different DMSA kits in-house, with SnCl2 concentrations at 200 and 400 μg and the composition of the other ingredients similar to Amersham kit. NaHCO3 (3.5%,0.4mL) was added to each kit to adjust the pH to 8.5. To the kit containing 400 μg of SnCl2, oxygen was bubbled through for 5 min. The radiochemical purity was measured using plastic backed TLC (Merck Silica Gel 60F) with the solvent system of n-Butanol: Acetic acid: water (3:2:3 v/v). The percentage purity of Tc-99m (V) DMSA (n=4) was 53.9 ± 3.6% after the addition of NaHCO3 which improved to 71.6 ±2.9% immediately after oxygen bubbling and peaked at 99±1.2% within 20 min. This was stable for 8 hrs at least. The results indicated that the fall in the levels of Tc-99m (m) DMSA was accompanied by a concomitant increase in the levels of Tc- 99m (V) DMSA which peaked at 98-100% after 20 min. Conversely, a purity level of 100 % was achieved in less than 10 min, when the kit containing 200 μg of SnCl2 was subjected to similar treatment as above. Kinetic studies show that it is desirable to use the product 20-30 min after oxygen

  20. The value of {sup 99m}technetium-MIBI scintiscanning for diagnostic evaluation of breast cancer; Stellenwert der {sup 99m}Technetium-MIBI-Szintigraphie in der Mammadiagnostik

    Hagedorn, K.; Kraemer, S.; Lang, N. [Universitaets-Frauenklinik, Erlangen (Germany); Schulz-Wendtland, R.; Bautz, W. [Universitaet Erlangen-Nuernberg (Germany) Institut fuer Diagnostische Radiologie; Kat, S.; Wolf, F. [Universitaet Erlangen-Nuernberg (Germany). Nuklearmedizinische Klinik

    1998-03-01

    We performed {sup 99m}Tc-MIBI scintiscanning in 42 patients with indications for surgery of mammary lesions, ascertained by palpation, mammography, ultrasonography, or MRI. We had a total of 62 histologically examined tumors for our analysis, comprising 24 benign tumors (10 fibroadenomas, 1 papilloma, 1 cyst, 1 lymph node, 10 mastopathies), 4 in-situ carcinomas, and 34 malignant tumors (32 duct carcinomas, 1 intramammary lymph node matastasis, 1 low-grade malignant sarcoma). The benign mammary gland tumors were not shown by contrast agent accumulation in the {sup 99m}Tc-MIBI scintiscans. Out of 14 carcinomas of a size less than 15 mm across, only 5 were detected by scintiscanning, and none of the in-situ carcinomas was revealed in the scintiscans. However, all malignomas of a size of 15 mm or more were detected by scintiscanning. The results of the comparative analysis of the diagnostic methods relating to sensitivity and specificity are (n=58, without CIS):{sup 9}9mTc-MIBI scintiscans: 73.5%/100%; mammography: 94,1%/62.5%; palpation:82.4%/91.7%; ultrasonography:94.1%/58.3%. As compared to the other four methods, {sup 9}9mTc-MIBI scintiscanning ranks last in terms of sensitivity, and is the best method interms of specificity. The high specificity shown by our study could not be confirmed by other studies, and the sensitivity is particularly restricted when tumors are small in size, or at unfavourable locations. The conclusion therefore is that this scintiscanning method is not to be recommended as a screening method, nor is it a method of choice for complementary diagnostic evaluation of breast lesions, except perhaps for a few specific cases. (orig./CB) [Deutsch] Wir fuehrten die {sup 99m}Tc-MIBI-Szintigraphie bei 42 Patientinnen mit operationsbeduerftigem Mammabefund durch, die zuvor palpatorisch, mammographisch, sonographisch und zum Teil mittels Magnetresonanztomographie der Mamma untersucht worden waren. Insgesamt konnten wir 62 histologisch untersuchte

  1. Effect of Tc99m Labeling on The Survival Rate of Dental Pulp Stem Cells

    Jabari F

    2014-02-01

    Full Text Available Background and Aim: Human dental pulp stem cells have substantial proliferative and differentiation potential. The isolated stem cells or progenitor cells of the pulp can differentiate into odontoblasts or /and osteoblast-like cells and aid in repair as well as reconstruction of tooth structure. Several ways have been introduced for isolation and tracing of these cells. The aim of this study was to isolate mesenchymal stem cells from deciduous dental pulps as well as labeling them with Technetium (Tc99m to investigate the effect of Tc labeling on the survival rate of stem cells. Materials and Methods: In this experimental study, exfoliated deciduous teeth of 6-11 year old children without any history of systemic disease were collected. Enzymatic and non-enzymatic methods were used to expedite cell isolation and isolated cells (10000 from dental pulp were mixed with 25 millicurie of Tc for tracing purposes. Individual cell activity as well as culture medium activation was evaluated separately afterwards. Data was analyzed using ANOVA statistical test. Results: Isolated dental pulp cells formed single cell derived colonies which showed fibroblast-like growth with solo cloning morphology. Specific staining of the cells indicated them to be stem cells and confirmed their differentiation into bone and fat. Moreover, Technetium significantly decreased the activity of cells. The survival rates of the cells in the period of 1,3,6,24,48 hours were reported to be 95.5%, 85.5%, 77.4%, 68.4%, and 57.3% respectively. Conclusion: The dental pulp stem cells have a significant capacity to differentiate into bone and fat. Tracing the cells with Tc M99 will reduce their survival rate over time.

  2. Sup(99m)Tc(Sn)-sucralfate; development of an instant labelling kit

    An instant labelling kit for the preparation of 99mTc(Sn)-sucralfate has been developed containing 500 mg sucralfate and 1 mg SnCl2 · 2 H2O. The labelling yield, in vitro stability and biodistribution indicate (bio)equivalence of 99mTc(Sn)-sucralfate and 99mTc(HSA)-sucralfate. The percentages of labelling obtained with the kit during a period of 8 months always exceeded 95%. The preparation kit is inexpensive and the labelling procedure fast and easy. (author)

  3. Comparison of technetium-99m-HM-PAO leukocytes with indium-111-oxine leukocytes for localizing intraabdominal sepsis

    Technetium-99m-HM-PAO [(99mTc]HM-PAO) leukocyte and indium-111-oxine (111In-oxine) leukocyte scanning were carried out simultaneously in 41 patients at 4 hr and 24 hr after reinjection to determine whether the 4-hr 99mTc scan could replace the 24-hr 111In scan for detecting intraabdominal sepsis. Abdominal infection was confirmed in 12 cases. The 4-hr 99Tc-leukocyte scan, the 4-hr 111In-leukocyte scan, and the 24-hr 111In-leukocyte scan yielded a sensitivity of 100%, 67%, and 100%, respectively, and a specificity of 62%, 90%, and 86%, respectively. The 24-hr 99mTc-leukocyte scan also produced a sensitivity of 100%, but it was falsely positive in all 29 cases without infection due to physiologic bowel uptake. False-positive 4-hr 99mTc-leukocyte scans were also produced by physiologic bowel uptake in seven cases all of whom had true-negative 4-hr and 24-hr 111In-leukocyte scans. Because of the high incidence of false-positive 4-hr [99mTc]HM-PAO leukocyte scans, it was concluded that they could not replace 24-hr 111In-leukocyte scans for detecting intraabdominal sepsis, and that serial 99mTc leukocyte scans starting earlier than 4 hr after reinjection must be evaluated

  4. Clinical application of Tc-99m HMPAO labeled leukocyte imaging in inflammatory disease

    A radionuclide imaging with Tc-99m HMPAO labeled leukocyte was performed in order to determine its clinical usefulness in inflammatory disease. The mixed leukocyte isolated from 40 ml of whole blood containing 5 ml of acid citrate dextrose A and 7 ml of 6% hydroxyethyl starch was incubated with 370 MBq (10 mCi) of Tc-99m HMPAO at 37degC for 30 minutes. Because the labeling efficiency of Tc-99m HMPAO labeled leukocyte was 60.2±6.3%, the procedure of washing Tc-99m leukocyte with 5 ml of physiological saline was necessary before intravenous injection, in order to remove the unlabeled Tc-99m HMPAO. The recoveries of Tc-99m leukocyte in the blood after intravenous injection were 41.1±6.7% at 5 minutes, 33.4±2.1% at 30 minutes, and 27.2±3.4% at 2 hours after injection. Moreover, the labeled leukocyte was not stained with trypan blue. Therefore, the biological activity of the Tc-99m leukocyte was maintained as that of In-111 oxine labeled leukocyte. In the 39 patients with clinical suspicion of inflammatory disease including 15 patients with acute and chronic infectious disease where both Tc-99m leukocyte and Ga-67 citrate imagings were performed, the sensitivity, specificity and accuracy for infectious disease were 47%, 100%, and 79% with Tc-99m leukocyte, and 67%, 79%, 74% with Ga-67 citrate. These results suggest that Tc-99m HMPAO labeled leukocyte imaging is promising for evaluating inflammatory disease because of much higher specificity, the ready availability of Tc-99m HMPAO, the good image quality, and the lower radiation dose to the patient. (author)

  5. The role of iodine-131 MIBG and technetium-99m DMSA(V) in evaluation of malignant disease

    Full text: The aim of our work is to establish the protocols of preparation and application of 99mTc DMSA (V) and 131 1 MIBG in the patient with malignant diseases. Methods and Results: The radiopharmaceutical DMSA (V) was in house prepared as a sterile, pyrogen-free, freeze-drier product under nitrogen. Each vial contain DMSA-1.0 mg and Stannous chloride dehydrate 0.4 mg with the final PH 2.0. Before labeling the kit was reconstituted by the addition of 0.5 ml sterile, pyrogen-free 3.5% NaHCO3. Reconstitution and labeling was performed by addition of sterile, pyrogen-free, isotonic sodium 99mtechnetium pertechnetate - 6 ml final volume. The product contains no antimicrobial preservative. After incubation of 15 min. and before use, limpidity of the solution after preparation, pH (∼8) and radioactivity was checked. The quality control of this radiopharmaceutical was effected by: I . Paper Chromatograpy (PC) using two solvens -acetone and 0.9% NaCl. 2. Instant Thin Layer Chromatography (ITLC) using mixture of the n-butanol:acetic acid:water (3:2:3). We evaluated the percentage of labeled complex technetium 99mTc DMSA (V), hydrolyzed and free technetium 99mTc. In every samples the labeling efficiency resulted more than 95%. The normal in vivo biodistribution of this radiopharmaceutical was monitored in normal rats using imaging as well as counting dissected tissues, 2 and 4 hours after application. The 131 1 MIBG was prepared by iodination of meta-iodo-benzylguanidinum-sulfarte. 3mg MIBG and 6mg ammonium sulfate were dissolved in ethanol-water 1:1 mixture and 1% CuSo4. Adding 2.5 - 10 mCi Iodine and evaporating the solution carefully, under infrared lamp for 45-60 minutes was performed radiolabeling procedure. After evaporation, the vial was placed into the furnace for a labeling reaction by heating for 40 minutes at temperature between 166-1750C. After labeling the vial was cooled completely, measured the activity of the melt and dissolved with 3-4 ml of Walpole

  6. Renogram studies with dogs, using the radioisotope technetium-99m DTPA

    In the dog extensive kidney pathology is often not diagnosed by conventional tests. In this study renograms were conducted on conscious healthy Beagle dogs using the radioisotope technetium-99m DTPA. Because of problems foreseen in keeping dogs immobile the study was also conducted using the sedative acepromazine maleate and the narcotic thiopentonesodium on the same Beagles. Renograms were also conducted on dogs with acute and chronic renal pathology. It was found that during the renogram procedure the animal must be completely immobile. Constant infusion narcosis with thiopentonesodium produced this immobility without affecting the renogram in normal dogs, however administration of a thiopentone bolus did affect the renogram. Sedation with acepromazine maleate had the effect of significantly increasing the second phase of the renogram and in addition significantly accelerated the excretion phase. These effects are thought to be due to a decreased bloodpressure with concomintent renal bloodpooling and retarded renal bloodflow. It would appear that radioisotope renograms are valuable in the diagnosis and prognosis of clinical cases of acute as well as chronic renal pathology. It is especially useful in identifying cases of compensated renal pathology where it is more sensitive than the conventional tests. It can differentiate between different degrees of pathology between the left and right kidney. Seen from an economic viewpoint the conventional tests give adequate information in the case of acute renal failure. Radioisotope renogram appears to hold great promise for both clinical and research applications. The equipment required for this application, however, is so costly that it would only be financially feasible for major centres such as a Faculty of Veterinary Science. Much information can be gained from referred clinical cases

  7. Postreperfusion myocardial technetium-99m-sestamibi defect corresponds to area at risk

    Poulsen, Runa Hyldgaard, E-mail: runa.poulsen@ki.au.dk [Clinical Institute, Aarhus University, DK-8000 Aarhus C (Denmark); Botker, Hans Erik [Department of Cardiology, Aarhus University Hospital, Skejby (Denmark); Rehling, Michael [Department of Nuclear Medicine, Aarhus University Hospital, Skejby (Denmark)

    2011-08-15

    Introduction: Technetium-99m-sestamibi (MIBI) is the most frequently used myocardial perfusion tracer in patients with ischemic heart disease. In patients with acute ST-elevation myocardial infarction, we previously found that the defect in myocardial MIBI uptake was the same in patients injected with MIBI before primary angioplasty and in patients injected immediately after successful treatment. Thus, reperfusion may not be followed by increased uptake of MIBI. Instead, the MIBI defect after reperfusion may reflect the area at risk (AAR) defined by MIBI injected before treatment. We intended to investigate whether myocardial imaging with MIBI administered after reperfusion reflects myocardial perfusion or rather the ischemic AAR. Methods: In 12 pigs, left anterior descending coronary artery was totally occluded for 45 min with an angioplasty balloon. After a 2-h reperfusion, MIBI was injected intravenously, and {sup 153}Gd-microspheres were injected in left atrium. AAR and infarct size (IS) were determined by histochemical staining. MIBI and microsphere distribution were evaluated by counting the sliced left ventricle on a gamma camera. Defects were defined as uptake less than 45% of maximum uptake. Results: The mean{+-}S.D. defect size as a fraction of left ventricle was for MIBI 21%{+-}5.5%, AAR 25%{+-}6.3%, IS 13%{+-}3.9% and microspheres defect size 7.3%{+-}5.5%. MIBI defect size overestimated IS (P=.0005) and microspheres defect size (P=.0001), but it was not significantly different from AAR (P=.30). Conclusion: In a porcine model of myocardial infarction after 45 min of ischemia, MIBI administered 120 min after reperfusion delineates AAR.

  8. Radioiodine therapy for Plummer's disease based on the thyroid uptake of technetium-99m pertechnetate

    The aim of this retrospective study was the evaluation of a TcTUs (global technetium-99m pertechnetate thyroid uptake under suppression)-based approach in 370 patients with thyroid autonomy (Plummer's disease) treated by radioiodine therapy (RIT) under standardised conditions. The analysis included 370 patients (309 females, 61 males; mean age 64±11.6 years) treated for thyroid autonomy [unifocal (UFA), 36.8%; multifocal (MFA), 55.7%; disseminated (DISA), 7.6%]. During RIT all patients were under thyroid suppression (TSH0.5 μU/l and/or TcTUs4 μU/ml). A dose of 350-450 Gy to the autonomous tissue resulted in a success rate of 97% in the UFA group and 81% in the MFA/DISA group. Decrease in total thyroid volume and TcTUs did not differ significantly between successfully treated patients and patients with persistent autonomy. Multivariate analysis of all 370 patients identified four independent factors that negatively influenced the therapeutic success: high pretherapeutic thyroid volume (P=0.0001; odds ratio: 1.017), high pretherapeutic TcTUs values (P=0.0001; odds ratio: 1.378), multifocal/disseminated autonomy (P=0.0056; odds ratio: 3.245) and low target dose (P=0.017; odds ratio: 0.997). It is concluded that the high success rate in the treatment of UFA indicates the concept of TcTUs-based RIT to be valid, but that in the therapy of MFA/DISA the target se has to be corrected if the total thyroid volume exceeds a critical threshold. (orig.)

  9. Water-pipe smoking effects on pulmonary permeability using technetium-99m DTPA inhalation scintigraphy

    Although extensive work has been done on cigarette smoking and its effects on pulmonary function, there are limited number of studies on water-pipe smoking. The effects of water-pipe smoking on health are not widely investigated. The aim of this study was to determine the effects of water-pipe smoking on pulmonary permeability. Technetium-99m DTPA inhalation scintigraphy was performed on 14 water-pipe smoker volunteers (all men, mean age 53.7±9.8) and 11 passive smoker volunteers (1 woman, 10 men, mean age 43.8±12). Clearance half-time (T 1/2) was calculated by placing a monoexponential fit on the time activity curves. Penetration index (PI) of the radioaerosol was also calculated. PI was 0.58±0.14 and 0.50±0.12 for water-pipe smokers (WPS) and passive smokers (PS) respectively. T 1/2 of peripheral lung was 57.3±12.7 and 64.6±13.2 min, central airways was 55.8±23.5 and 80.1±35.2 min for WPS and PS, respectively (p≤0.05). Forced expiratory volume in one second/forced vital capacity (FEV1/FVC)% was 82.1±8.5 (%) and 87.7±6.5 (%) for WPS and PS, respectively (0.025< p≤0.05). We suggest that water-pipe smoking effects pulmonary epithelial permeability more than passive smoking. Increased central mucociliary clearance in water-pipe smoking may be due to preserved humidity of the airway tracts. (author)

  10. Effect of histamine on technetium-99m excretion by gastric mucosa

    The ability of histamine to increase excretion of /sup 99m/Te by gastric mucosa was investigated in dogs with Heidenhain pouches and denervated antral pouches. Histamine increased Heidenhain pouch /sup 99m/Te output in a dose-related manner, and /sup 99m/Te output was related linearly to acid output. Antral pouch /sup 99m/Te output was unchanged by increasing doses of histamine. The study suggests that concomitant use of histamine may improve the accuracy of /sup 99m/Te scanning in the clinical diagnosis of conditions caused by ectopic gastric mucosa

  11. Migration of 99mTC-hexamethylpropylene amine oxime (HMPAO) labeled immature and mature dendritic cells in the mouse

    The purpose of this study is to evaluate migration of technetium-99 m hexamethylpropylene amine oxime (99mTc-HMPAO) labeled immature and mature dendritic cells (DC) in the mouse. DC were collected from bone marrow (BM) of tibiae and femurs of mice. Immature and mature CD from BM cells were radiolabeled with 99mTc-HMPAO. To evaluate the functional and phenotypic changes of DC from radiolabeling, the allogeneic mixed lymphocyte reaction (MLR) and fluorescence-activated cell sorting (FACS) analysis were performed before and after labeling with 99mTc-HMPAO. Migration of intravenously injected DC (iv-DC) was assessed by serial gamma camera images of mice with or without subcutaneous tumor. Percent injected dose per gram (%ID/g) was calculated in lungs, liver, spleen, kidneys, and tumor through dissection of each mice after 24 hours of injection. Labeling efficiency of immature and mature DC were 60.4 ± 5.4% and 61.8 ± 6.7%, respectively. Iv-DC initially appeared in the lungs, then redistributed mainly to liver and spleen. Migration of mature DC to spleen was significantly higher than that of immature DC (38.3 ± 4.0% vs 32.2 ± 4.1% in control group, 40.4 ± 4.1% vs 35.9 ± 3.8% in tumor group; ρ 99mTc-HMPAO labeled immature and mature DC. Migration of mature DC to spleen and tumor was higher than that of immature DC when they were i.v. injected

  12. Measurement of renal function by calculation of fractional uptake of technetium-99m dimercaptosuccinic acid

    The purpose of this study was to set up normal values of the fractional uptake (FU) of technetium-99m dimercaptosuccinic acid in adults and in the pediatric population, as well as to evaluate the validity of this parameter at different levels of renal function. A total of 86 subjects was divided into seven groups. In group A there were 23 potential kidney donors and in group B, 18 children in remission after a first urinary tract infection. Another three groups consisted of patients with diabetes i.e. group C, seven patients with normal values of albuminuria, group D, 16 patients with microalbuminuria and group E, five patients with macroalbuminuria. In group F, there were ten patients with a well-functioning transplanted kidney and in group G, seven patients with suspected acute rejection. The procedure began with the quantification of the doses of 99mTc-DMSA to be injected and the measurement of the empty syringe lying on the gamma camera collimator. Thereafter, four planar views of the kidneys were acquired three hours after the injection. The counts from the posterior and anterior views were subtracted for background and corrected for radioactive decay time and patient thickness. The FU was calculated by the geometric mean of counts per second from the posterior and anterior view. It was expressed as a fraction of the injected dose. The mean values of FU in healthy adults were 0.227 ± 0.077 for one kidney and 0.454 ± 0.146 for both kidneys. The mean values of FU for the left and right kidney were 0.225± 0.071 and 0.229 ± 0.079, respectively. In children, the mean values were 0.220 ± 0.092 for one kidney and 0.432 ± 0.094 for both kidneys. The highest values of FU of 0.322 ± 0.078 (0.644 ± 0.138 for both kidneys) were measured in group C. In group D, FU was 0.185 ± 0.065 (0.361 ± 0.125 for both kidneys) and in group E 0.082 ± 0.040 (0.163 ± 0.080 total). In patients with a transplanted kidney, fractional uptake was 0.162 ± 0.039 in group F and 0

  13. Influence of biflorin on the labelling of red blood cells, plasma protein, cell protein, and lymphocytes with technetium-99m: in vitro study Influência da biflorina na marcação do tecnécio-99m em células vermelhas do sangue, proteínas do plasma, proteínas celulares e em linfócitos: estudos in vitro

    Thiago M. Aquino

    2007-06-01

    Full Text Available In this paper we report the results of an in vitro study involving the influence of biflorin (an o-quinone isolated from Capraria biflora L. that has potent antimicrobial activity on the Tc-99m labeling of red blood cells, plasma protein, cells protein, and lymphocytes. Blood was withdrawn from Wistar rats and incubated with various concentrations of biflorin, and solutions of stannous chloride and Tc-99m were added. Plasma (P and red blood cells (RBC were isolated, precipitated, and centrifuged, and soluble (SF and insoluble (IF fractions were isolated. The results show that the highest concentration (100% of biflorin is able to reduce the uptake of Tc-99m (%ATI on RBC and the fixation on IF-P. To study the influence of biflorin on 99mTc lymphocyte labeling, human blood was submitted to a technique with Ficoll-Hypac and centrifuged, and white cells were isolated. Lymphocytes (2.5 mL; 1.0 x 10(6 cells/mL were obtained and a 0.2 mL solution was incubated with biflorin (0.1 mL. Solutions of stannous chloride and 99mTc were added. Lymphocytes were separated and the %ATI bound in these cells was evaluated. A reduction in %ATI (from 97.85 ± 0.99 to 88.86 ± 5 was observed for RBC and for IF-P (73.24 ± 5.51 to 20.72 ± 6.95. In this case the results showed no decrease in %ATI for the lymphocytes with biflorin.Neste artigo relatam-se os resultados de um estudo in vitro envolvendo a influência da biflorina (uma o-quinona isolada de Capraria biflora L. que possui uma potente atividade antimicrobiana na marcação do Tc-99m em células vermelhas do sangue, proteínas do plasma, proteínas celulares e em linfócitos. O sangue foi coletado de ratos Wistar e incubado com várias concentrações de biflorina, e soluções de cloreto estanoso (SnCl2 adicionando-se Tc-99m. O plasma (P e as células vermelhas do sangue (CVS foram isolados, precipitados e centrifugados, isolando-se as frações solúveis (FS e insolúveis (FI. A maior concentração de

  14. Investigation of four 99mTc-labeled bacteriophages for infection-specific imaging

    Introduction: This study investigated radiolabeled bacteriophages for specific detection of infection through gamma imaging. Previously, a 99mTc-labeled M13 phage demonstrated specific binding for its host Escherichia coli in vitro and in mice through imaging. Methods: This study was extended to phages P22, E79, VD-13 and phage 60. Each was radiolabeled with 99mTc using the chelator MAG3, and were evaluated for binding to host and non-host bacteria in vitro and in a mouse infection model. Results: In vitro, each 99mTc-phage bound to its host at least 4-fold higher than to non-host bacteria. For example, 99mTc-E79 showed 10- to 20-fold greater binding to host Pseudomonas aeruginosa compared to non-host Escherichia coli and Salmonella enterica, and 99mTc-phage 60 showed 20-fold greater binding to host Klebsiella pneumoniae over non-hosts. Mice received host or non-host bacteria in one thigh, and 3 h later, the 99mTc-phages were administered intravenously. After a further 3 h, the tissues were counted. Liver accumulation was highest for 99mTc-E79, averaging 39% compared to an average of 13% for the other 99mTc-phages. Animals infected with host bacteria showed infected thigh/normal thigh ratios of 14.2 for 99mTc-E79, 2.9 for 99mTc-P22, 3.5 for 99mTc-VD-13 and 2.1 for 99mTc-phage 60. Conclusions: Although specific host binding was observed in vitro for each of these four 99mTc-phages, only 99mTc-E79 showed specificity for its host in an in vivo model

  15. Investigation of four {sup 99m}Tc-labeled bacteriophages for infection-specific imaging

    Rusckowski, Mary [Division of Nuclear Medicine, Department of Radiology, University of Massachusetts Medical School, Worcester, MA 01655-0243 (United States)], E-mail: mary.rusckowski@umassmed.edu; Gupta, Suresh; Liu Guozheng; Dou Shuping; Hnatowich, Donald J. [Division of Nuclear Medicine, Department of Radiology, University of Massachusetts Medical School, Worcester, MA 01655-0243 (United States)

    2008-05-15

    Introduction: This study investigated radiolabeled bacteriophages for specific detection of infection through gamma imaging. Previously, a {sup 99m}Tc-labeled M13 phage demonstrated specific binding for its host Escherichia coli in vitro and in mice through imaging. Methods: This study was extended to phages P22, E79, VD-13 and phage 60. Each was radiolabeled with {sup 99m}Tc using the chelator MAG{sub 3}, and were evaluated for binding to host and non-host bacteria in vitro and in a mouse infection model. Results: In vitro, each {sup 99m}Tc-phage bound to its host at least 4-fold higher than to non-host bacteria. For example, {sup 99m}Tc-E79 showed 10- to 20-fold greater binding to host Pseudomonas aeruginosa compared to non-host Escherichia coli and Salmonella enterica, and {sup 99m}Tc-phage 60 showed 20-fold greater binding to host Klebsiella pneumoniae over non-hosts. Mice received host or non-host bacteria in one thigh, and 3 h later, the {sup 99m}Tc-phages were administered intravenously. After a further 3 h, the tissues were counted. Liver accumulation was highest for {sup 99m}Tc-E79, averaging 39% compared to an average of 13% for the other {sup 99m}Tc-phages. Animals infected with host bacteria showed infected thigh/normal thigh ratios of 14.2 for {sup 99m}Tc-E79, 2.9 for {sup 99m}Tc-P22, 3.5 for {sup 99m}Tc-VD-13 and 2.1 for {sup 99m}Tc-phage 60. Conclusions: Although specific host binding was observed in vitro for each of these four {sup 99m}Tc-phages, only {sup 99m}Tc-E79 showed specificity for its host in an in vivo model.

  16. Evaluation of technetium 99m cyclobutylpropylene amine oxime as a potential brain perfusion imaging agent for SPET

    99mTc-labelled d,l-cyclobutylpropylene amine oxime (99mTc-CBPAO) has been developed as a brain imaging agent for single photon emission tomography (SPET). 99mTc-CBPAO can be prepared using a simple labelling procedure suitable for routine clinical use. It has a high in vitro stability, as has been demonstrated by high-pressure liquid chromatography (HPCL) analysis. This shows that 3 h after labelling, less than 5% of the primary lipophilic complex which is capable of crossing the blood-brain barrier (BBB) converts to a secondary hydrophilic complex. Brain uptake (% dose/g wet tissue) of 99mTc-CBPAO, determined at 5 and 30 min after injection in two groups of six adult male Sprague-Dawley rats, was found to be 0.74±0.06 and 0.73±0.13 (mean±SD), respectively. These values are not significantly different from those obtained repeating the experiment with 99mTc-labelled hexamethylpropylene amine oxime (99mTc-HMPAO) (0.72±0.15 at 5 min and 0.88±0.24 at 30 min after injection). Since the rat brain uptake of 99mTc-CBPAO remained unchanged for a period of time suitable for tomographic study, the comparison of the two tracers was extended to two groups of ten patients. The latter were affected by neurological and psychiatric disorders and were studied with SPET. Human brain uptake (% dose/cc cortical grey matter) of 99mTc-CBPAO and 99mTc-HMPAO were 3.04±0.57 and 4.22±0.46 (mean x 10-3±SD x 10-3), respectively, with a 32% significant difference. In two other groups of five patients, the first transit time-activity curves of the two tracers were compared. From the analysis of these curves we suggest that 99mTc-CBPAO has a higher binding effect on blood components and/or a higher degradation rate in blood than that of 99mTc-HMPAO. This may account for the reduced human brain uptake. In conclusion, SPET images of 99mTc-CBPAO reflect blood perfusion, and they have a good diagnostic quality. The main advantage of 99mTc-CBPAO is its in vitro stability; however, 99m

  17. Quantitative comparison of technetium-99m tetrofosmin and thallium-201 images of the thyroid and abnormal parathyroid glands

    Giordano, A.; Meduri, G.; Calcagni, M.L. [Catholic University of the Sacred Heart, Department of Nuclear Medicine, Roma (Italy); Marozzi, P.; Ficola, U.; Vaccaro, A. [Department of Nuclear Medicine, Cervello Hospital, Palermo (Italy); Rubini, G. [Department of Nuclear Medicine of the University, Bari (Italy); Attard, M.; Li Puma, M. [Department of Endocrinology, Cervello Hospital, Palermo (Italy); Ricci, R. [Department of Pathology, Catholic University of the Sacred Heart, Rome (Italy); Corsello, S. [Department of Endocrinology, Catholic University of the Sacred Heart, Rome (Italy)

    1999-08-01

    The aim of the study was to quantitatively compare the scintigraphic images of the thyroid and abnormal parathyroid glands obtained with technetium-99m tetrofosmin and thallium-201 in patients with hyperparathyroidism. Forty-six patients with hyperparathyroidism underwent {sup 201}Tl (74 MBq), {sup 99m}Tc-pertechnetate (74 MBq) and {sup 99m}Tc-tetrofosmin (555-740 MBq) scintigraphy in a single session. Image analysis included the computation of the thyroid/background ratio in the whole study population and the parathyroid/background ratio, parathyroid/thyroid ratio and diagnostic sensitivity in 17 patients who underwent parathyroid surgery. The pertechnetate subtraction technique was used. {sup 201}Tl and {sup 99m}Tc-tetrofosmin showed a similar thyroid/background ratio (1.79{+-}0.41 and 1.81{+-}0.47, respectively, P=NS); however, {sup 99m}Tc-tetrofosmin showed a higher parathyroid/background ratio than {sup 201}Tl (2.06{+-}0.54 vs 1.79{+-} 0.50, P=0.007). Despite the superior quality of {sup 99m}Tc-tetrofosmin images, both tracers showed identical sensitivity in detecting enlarged parathyroid glands in patients with primary hyperparathyroidism (89%) and in those with secondary hyperparathyroidism (50%). (orig.) With 2 figs., 3 tabs., 15 refs.

  18. First experiences with technetium-99m furifosmin as tumour-seeking agent in breast cancer and recurrent ovarian cancer

    Recent in vitro studies suggest that technetium-99m furifosmin may have tumour-seeking properties. We analysed the diagnostic value of 99mTc-furifosmin scintigraphy in nine patients with documented carcinoma of the breast and in eight patients with continued recurrent ovarian cancer. In the breast, 99mTc-furifosmin failed to visualize the primary malignant tumour and the associated malignant lymph nodes in all patients. In contrast, multiple sites of increased tracer uptake were demonstrated in one patient with acute benign inflammatory breast disease. In four of eight patients with recurrent ovarian cancer, 99mTc-furifosmin scintigraphy demonstrated early (5 min p.i.) localized increased uptake corresponding to adhesions to the bowel as diagnosed by computed tomography, but failed to reveal further abnormalities in all patients. The present study demonstrates that furifosmin is of no value in the imaging of breast cancer and recurrent ovarian cancer. These results do not continue the pattern observed in cell culture studies and are quite in contrast to the findings of mammoscintigraphy using 99mTc-methoxyisobutylisonitrile and 99mTc-tetrofosmin. (orig.). With 3 figs., 2 tabs