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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

    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)

  17. 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)

  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. 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)

  20. 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.

  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. 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.)

  17. 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.)

  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. 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...

  3. 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...

  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

    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

    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.

  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. 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

  12. 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

  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. 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

  20. 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

  1. 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.

  2. 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

  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. 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

  6. 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

  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

    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.

  20. 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)

  1. 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)

  2. 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)

  3. 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)

  4. 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

  5. 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.

  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. 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.

  6. 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

  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. 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.

  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

    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

  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. 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...

  1. 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)

  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. 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)

  5. 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.

  6. 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)

  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. 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)

  9. 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.)

  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 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)

  1. 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.)

  2. 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.)

  3. 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.)

  4. 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.)

  5. 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

  6. 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.

  7. Novel 99mTc labeled

    FAN; Caiyun

    2006-01-01

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  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