uu.seUppsala universitets publikationer
Ändra sökning
Avgränsa sökresultatet
12 51 - 71 av 71
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 51.
    Sundberg, Åsa Liljegren
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Blomquist, Erik
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Carlsson, Jörgen
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Steffen, Ann-Chalott
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Gedda, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Cellular retention of radioactivity and increased radiation dose: Modelexperiments with EGF-dextran2003Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 30, nr 3, s. 303-315Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Targeting of tumor cells with radiolabeled biomolecules is a possible approach to inactivate disseminated tumor cells. However, rapid degradation of the biomolecules after cellular internalization and subsequent excretion of the radioactivity is a problem. We studied the possibility of using dextran as a carrier of radionuclides to improve the intracellular retention. An EGF-dextran conjugate, aimed for targeting of tumor cells overexpressing the EGF-receptor, was used as model. Retention tests were performed with (125)I on different parts: [(125)I]-EGF-dextran-[(125)I], [(125)I]-EGF-dextran and EGF-dextran-[(125)I]. Comparisons were made with [(125)I]-EGF. The radiolabeled compounds were incubated with cultured glioma cells for different times. The cellular retention of radioactivity was then measured for up to 24 h. Expected radiation doses at the cellular level were calculated assuming that (131)I, instead of (125)I, was coupled to EGF and EGF-dextran. The results indicated that the EGF-part of the conjugate was degraded and the EGF-attached radioactivity was rapidly excreted, whereas radioactivity on dextran was retained intracellularly to a high degree, i.e. 70-80% of the radioactivity bound to dextran was still cell-associated after 24 h. The retention after 24 h was significantly higher (p < 0.001) when the radioactivity was on the dextran instead of the EGF-part. The radiolabeled EGF-dextran had a notably high specific radioactivity; up to 11 MBq/microg. There was potential for at least hundred times increased radiation dose per receptor interaction when the radioactivity was on the dextran part. The advantage with radioactivity on the dextran part was the high cellular retention and the high specific radioactivity (higher than previously reported for other residualizing labels) without severe loss of receptor specific binding. Thus, dextran seems suitable as a carrier of radionuclides aimed for therapy and gives potential for a highly increased radiation dose.

  • 52.
    Sundin, Johanna
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Tolmachev, Vladimir
    Koziorowski, Jacek
    Carlsson, Jörgen
    Lundqvist, Hans
    Welt, Sydney
    Larson, Steven
    Sundin, Anders
    High yield direct 76Br-bromination of monoclonal antibodies using Cloramine-T1999Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 26, nr 8, s. 923-929Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Monoclonal antibody (MAb) A33 was labeled with the positron emitter 76Br (T(1/2) = 16.2 h). Direct labeling was done using the conventional chloramine-T method. After optimization of the labeling conditions, a maximum yield (mean +/- max error) of 77 +/- 2% was obtained at pH 6.8. In vitro binding of 76Br-A33 to SW1222 colonic cancer cells showed that the immunoreactivity was retained. Also, the MAbs 38S1 and 3S193 and the peptide hEGF were 76Br-labeled, resulting in labeling yields (mean +/- max error) of 75 +/- 3%, 63 +/- 4%, and 73 +/- 0.1%, respectively. We conclude that antibodies and peptides can be labeled conveniently with 76Br for the purpose of whole-body tumour imaging by positron emission tomography.

  • 53.
    Sundín, Anders
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för radiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Eriksson, Barbro
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Bergström, Mats
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Bjurling, Peter
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Lindner, Karl-Johan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Öberg, Kjell
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Demonstration of [11C]5hydroxy-L-tryptophan uptake and decarboxylation in carcinoid tumors by specific positioning labeling in poistron tomography2000Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 27, nr 1, s. 33-41Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In three patients with carcinoid liver and/or lymph node metastases, we studied the process of tumor tracer uptake and decarboxylation by means of positron emission tomography (PET) using 5-hydroxy-L-tryptophan (5-HTP) 11C-labeled in the beta-position (HTP) and later the same day with 5-HTP 11C-labeled in the carboxyl group (HTC). With HTP, in which the 11C-label follows the molecule through decarboxylation to form 11C-serotonin, a high tumor accumulation of the tracer was found. With HTC, in which the label is rapidly eliminated from the tissues as 11CO2 if decarboxylation takes place, there was virtually no uptake by the tumors. By utilizing data from PET scanning with both tracers, we could quantify the decarboxylation rate and tissue accumulation of [11C]-serotonin and hence the enzymatic action of aromatic amino acid decarboxylase.

  • 54.
    Svedberg, Marie M.
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för folkhälso- och vårdvetenskap, Geriatrik.
    Rahman, Obaidur
    Hall, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för folkhälso- och vårdvetenskap, Geriatrik.
    Preclinical studies of potential amyloid binding PET/SPECT ligands in Alzheimer's disease2012Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 39, nr 4, s. 484-501Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Visualizing the neuropathological hallmarks amyloid plaques and neurofibrillary tangles of Alzheimer's disease in vivo using positron emission tomography (PET) or single photon emission computed tomography will be of great value in diagnosing the individual patient and will also help in our understanding of the disease. The successful introduction of [C-11]PIB as a PET tracer for the amyloid plaques less than 10 years ago started an intensive research, and numerous new compounds for use in molecular imaging of the amyloid plaques have been developed. The candidates are based on dyes like thioflavin T, Congo red and chrysamine G, but also on other types such as benzoxazoles, curcumin and stilbenes. In the present review, we present methods of the radiochemistry and preclinical evaluation as well as the main properties of some of these compounds.

  • 55.
    Syvänen, Stina
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för folkhälso- och vårdvetenskap, Geriatrik.
    Russmann, Vera
    Verbeek, Joost
    Eriksson, Jonas
    Department of Nuclear Medicine & PET Research, VU University Medical Center, Amsterdam, The Netherlands.
    Labots, Maaike
    Zellinger, Christina
    Seeger, Natalie
    Schuit, Robert
    Rongen, Marissa
    van Kooij, Rolph
    Windhorst, Albert D.
    Lammertsma, Adriaan A.
    de Lange, Elizabeth C.
    Voskuyl, Rob A.
    Koepp, Matthias
    Potschka, Heidrun
    [C-11]quinidine and [C-11]laniquidar PET imaging in a chronic rodent epilepsy model: Impact of epilepsy and drug-responsiveness2013Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 40, nr 6, s. 764-775Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction: To analyse the impact of both epilepsy and pharmacological modulation of P-glycoprotein on brain uptake and kinetics of positron emission tomography (PET) radiotracers [C-11]quinidine and [C-11]laniquidar.

    Methods: Metabolism and brain kinetics of both [C-11]quinidine and [C-11]laniquidar were assessed in naive rats, electrode-implanted control rats, and rats with spontaneous recurrent seizures. The latter group was further classified according to their response to the antiepileptic drug phenobarbital into "responders" and "non-responders". Additional experiments were performed following pre-treatment with the P-glycoprotein modulator tariquidar.

    Results: [C-11]quinidine was metabolized rapidly, whereas [C-11]laniquidar was more stable. Brain concentrations of both radiotracers remained at relatively low levels at baseline conditions. Tariquidar pre-treatment resulted in significant increases of [C-11]quinidine and [C-11]laniquidar brain concentrations. In the epileptic subgroup "non-responders", brain uptake of [C-11]quinidine in selected brain regions reached higher levels than in electrode-implanted control rats. However, the relative response to tariquidar did not differ between groups with full blockade of P-glycoprotein by 15 mg/kg of tariquidar. For [C-11]laniquidar differences between epileptic and control animals were only evident at baseline conditions but not after tariquidar pretreatment.

    Conclusions: We confirmed that both [C-11]quinidine and [C-11]laniquidar are P-glycoprotein substrates. At full P-gp blockade, tariquidar pre-treatment only demonstrated slight differences for [C-11]quinidine between drug-resistant and drug-sensitive animals.

  • 56.
    Takahashi, Kayo
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Bergström, Mats
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Frändberg, Pernilla
    Vesström, Eva-Lotta
    Watanabe, Yasuyoshi
    Långström, Bengt
    Imaging of aromatase distribution in rat and rhesus monkey brains with [C-11]vorozole2006Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 33, nr 5, s. 599-605Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aromatase is an enzyme that converts androgens to estrogens and may play a role in mood and mental status. The aim of this study was to demonstrate that brain aromatase distribution could be evaluated with a novel positron emission tomography (PET) tracer [C-11]vorozole. Vorozole is a nonsteroidal aromatase inhibitor that reversibly binds to the heme domain of aromatase. In vitro experiments in rat brain, using frozen section autoradiography, illustrated specific binding in the medial amygdala (MA), the bed nucleus of stria terminalis (BST) and the preoptic area (POA) of male rat brain. Specific binding in female rat brain was found in the MA and the BST; however, the signals were lower than those of males. The K-d of [C-11]vorozole binding to aromatase in MA was determined to be 0.60 +/- 0.06 nM by Scatchard plot analysis using homogenates. An in vivo PET study in female rhesus monkey brain demonstrated the uptake of [C-11]vorozole in the amygdala, where the uptake was blocked by the presence of excess amounts of unlabeled vorozole. Thus, this tracer has a high affinity for brain aromatase and could have a potential for in vivo aromatase imaging. This technique might enable the investigation of human brain aromatase in healthy and diseased persons.

  • 57.
    Tolmachev, Vladimir
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Bernhardt, Peter
    Forssell-Aronsson, Eva
    Lundqvist, Hans
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    114mIn, a candidate for radionuclide therapy: low-energy cyclotron production and labeling of DTPA-D-phe-octreotide2000Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 27, nr 2, s. 183-188Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A method for production of carrier-free (114m)In (half-life 49.5 days), which is a potential radionuclide for radionuclide therapy of slowly growing tumors, is presented. A target consisting of five enriched cadmium ((114)Cd) foils, each 50 microm thick, was irradiated by protons (from 12.6-6.5 MeV) giving a target yield of 0. 8 MBq/microAh. A simple and cost-efficient thermal diffusion method was used for the separation. The irradiated target foils were heated for 2 h at 306 degrees C and then etched in 0.05 M HCl. The obtained cadmium/indium solution was purified using a cation ion-exchange resin (AG 1 x 8, Bio-Rad Laboratories, Hercules, CA USA). An overall yield of approximately 60% was obtained, whereas the loss of the target material was <1% per separation cycle. The (114m)In production gave (114m)In with high specific radioactivity and was successfully used to label diethylenetriamine pentaacetic acid (DTPA)-D-Phe-octreotide. Furthermore, no difference in biodistribution between [(114m)In]- and [(111)In]-DTPA-D-Phe(1)-octreotide in tumor-bearing nude mice was seen. The high radionuclide uptake in the tumors indicates a good receptor binding of the labeled octreotide.

  • 58.
    Tolmachev, Vladimir
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för biomedicinsk strålningsvetenskap.
    Feldwisch, Joachim
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för biomedicinsk strålningsvetenskap.
    Lindborg, Malin
    Baastrup, Barbro
    Sandström, Mattias
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för onkologi.
    Orlova, Anna
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för biomedicinsk strålningsvetenskap.
    Influence of an aliphatic linker between DOTA and synthetic Z(HER2:342) Affibody molecule on targeting properties of the (111)In-labeled conjugate2011Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 38, nr 5, s. 697-706Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction: Affibody molecules are small (similar to 6.5 kDa) scaffold proteins suitable for radionuclide imaging of rumor-associated molecular targets. Site-specific labeling of Affibody molecules made by peptide synthesis can be achieved by coupling a chelator to N-terminus in the last synthesis step. The goal of this study was to evaluate the influence of a 6-aminohexanoic linker between DOTA and Z(HER2:342) on targeting properties of (111)In-labeled conjugate. Methods: A DOTA-conjugated 6-aminohexanoic linker-containing variant Of Z(HER2:342) (ABY-003) was produced by peptide synthesis, and the in vitro binding affinity, specificity and cellular processing were evaluated. The biodistribution of (111)In-ABY-003 in normal mice was compared to (111)In-ABY-002 (DOTA-Z(HER2:342-pep2)) lacking the linker. Tumor-targeting properties of (111)In-ABY-003 were evaluated in mice bearing HER2-expressing xenografts. Results: The dissociation constant of ABY-003 was in the low picomolar range, slightly higher than for ABY-002. (111)In-ABY-003 bound specifically to HER2-expressing cells in vitro. The cellular retention was efficient but slightly worse than for (111)In-ABY-002. In normal mice, the clearance of (111)In-ABY-003 from blood and other tissues was slightly but significantly faster compared to (111)In-ABY-002. Targeting of HER2-expressing xenografts by (111)In-ABY-003 was receptor-specific. Due to faster clearance, the tumor-to-blood ratio for (111)In-ABY-003 at 4 h postinjection was improved compared to (111)In-ABY-002. The capacity of (111)In-ABY-003 to visualize HER2-expressing tumors was confirmed by gamma camera imaging. Conclusions: A 6-aminohexanoic linker between the DOTA chelator and N-terminus of synthetic Z(HER2:342) had a measurable effect on affinity, cellular retention of radioactivity and blood clearance. The linker might be used for modulation of targeting properties of Affibody molecules.

  • 59.
    Tolmachev, Vladimir
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för biomedicinsk strålningsvetenskap.
    Hofström, Camilla
    Malmberg, Jennie
    Ahlgren, Sara
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för biomedicinsk strålningsvetenskap.
    Orlova, Anna
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för biomedicinsk strålningsvetenskap.
    Gräslund, Torbjörn
    HEHEHE: a new chelator for [Tc-99m(CO)(3)](+)-labeling assembling His(6)-tag in protein purification2010Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 37, nr 6, s. 698-698Artikel i tidskrift (Övrigt vetenskapligt)
  • 60.
    Tolmachev, Vladimir
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för biomedicinsk strålningsvetenskap.
    Wallberg, Helena
    Feldwisch, Joachim
    Orlova, Anna
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för biomedicinsk strålningsvetenskap.
    HER2 targeting with Tc-99m-labeled second generation synthetic Affibody molecule2010Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 37, nr 6, s. 705-706Artikel i tidskrift (Övrigt vetenskapligt)
  • 61.
    Varasteh, Zohreh
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Mitran, Bogdan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Rosenström, Ulrika
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Velikyan, Irina
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Rosestedt, Maria
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Lindeberg, Gunnar
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Klinisk fysiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Radiologi.
    Larhed, Mats
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Tolmachev, Vladimir
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Medicinsk strålningsvetenskap.
    Orlova, Anna
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    The effect of macrocyclic chelators on the targeting properties of the 68Ga-labeled gastrin releasing peptide receptor antagonist PEG2-RM262015Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 42, nr 5, s. 446-454Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction

    Overexpression of gastrin-releasing peptide receptors (GRPR) has been reported in several cancers. Bombesin (BN) analogs are short peptides with a high affinity for GRPR. Different BN analogs were evaluated for radionuclide imaging and therapy of GRPR-expressing tumors. We have previously investigated an antagonistic analog of BN (D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2, RM26) conjugated to NOTA via a PEG2 spacer (NOTA-PEG2-RM26) labeled with 68Ga, 111In and Al18F. 68Ga-labeled NOTA-PEG2-RM26 showed high tumor-to-organ ratios.

    Methods

    The influence of different macrocyclic chelators (NOTA, NODAGA, DOTA and DOTAGA) on the targeting properties of 68Ga-labeled PEG2-RM26 was studied in vitro and in vivo.

    Results

    All conjugates were labeled with generator-produced 68Ga with high yields and demonstrated high stability and specific binding to GRPR. The IC50 values of natGa-X-PEG2-RM26 (X = NOTA, DOTA, NODAGA, DOTAGA) were 2.3 ± 0.2, 3.0 ± 0.3, 2.9 ± 0.3 and 10.0 ± 0.6 nM, respectively. The internalization of the conjugates by PC-3 cells was low. However, the DOTA-conjugated analog demonstrated a higher internalization rate compared to other analogs. GRPR-specific uptake was found in receptor-positive normal tissues and PC-3 xenografts for all conjugates. The biodistribution of the conjugates was influenced by the choice of the chelator moiety. Although all radiotracers cleared rapidly from the blood, [68Ga]Ga-NOTA-PEG2-RM26 showed significantly lower uptake in lung, muscle and bone compared to the other analogs. The uptake in tumors (5.40 ± 1.04 %ID/g at 2 h p.i.) and the tumor-to-organ ratios (25 ± 3, 157 ± 23 and 39 ± 4 for blood, muscle and bone, respectively) were significantly higher for the NOTA-conjugate than the other analogs.

    Conclusions

    Chelators had a clear influence on the biodistribution and targeting properties of 68Ga-labeled antagonistic BN analogs. Positively charged [68Ga]Ga-NOTA-PEG2-RM26 provided a low kidney radioactivity uptake, high affinity, high tumor uptake and high image contrast.

  • 62. Velikyan, Irina
    et al.
    Beyer, Gerd J.
    Bergström-Pettermann, Elisabeth
    Johansen, Pernilla
    Bergström, Mats
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    The importance of high specific radioactivity in the performance of Ga-68-labeled peptide.2008Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 35, nr 5, s. 529-536Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Use of Ga-68-labeled peptides in diagnosis, dosimetry, therapy planning and follow-up of response to chemo- and radiotherapy requires accurate quantification of tracer binding characteristics in vivo, which may be influenced by the specific radioactivity (SRA) of the tracer. Systematic study of the complexation reaction of DOTA-D-Phe(1)-Tyr(3)-Octreotide (DOTATOC, where DOTA is the chelator 1,4,7,10-tetrauzacyclododecane-1,4,7,10-tetraacetic acid) with Ga-67, Ga-68, Ga-69,Ga-71 and in the presence of competing metal cations [Al(III), Fe(III), In (III)] was performed using conventional and microwave heating techniques and assessed by mass spectrometry. Saturation binding of Ga-68-DOTATOC to Rhesus monkey brain slices was performed using frozen section autoradiography. High SRA was necessary in order to characterize the saturation binding of Ga-68-DOTATOC to somatostatin receptors in Rhesus monkey brain sections. The complexation of Ga(III) with DOTATOC suggested more favorable formation compared to Fe(III) and In(III). The microwave heating mode might influence the selectivity of the complexation reaction, especially when comparing the behavior of Ga(III) and In(III). Al(III)was less critical with contamination and could be tolerated up to a concentration equal to that of the peptide bioconjugate. The SRA of Ga-67-DOTATOC and Ga-67-NODAGA-TATE (NODAGA-Tyr(3)-Octreotate, where NODAGA is 1,4,7-triazacyclononaiie-1-glutaric acid-4,7-diacetic acid) exceeded literature data by a factor of 7 and 5-15, respectively. High SRA was critical for providing sufficient contrast and accurate quantification of PET images. Microwave heating mode apart from the acceleration of the labeling reaction also improved the selectivity of the complexation reaction towards gallium. Fe(III) was shown to be the most critical competitor deteriorating the Ga-68-labeling efficiency.

  • 63.
    Velikyan, Irina
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Rosenström, Ulrika
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Estrada, Sergio
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Ljungvall, Ingrid
    Haggstrom, Jens
    Eriksson, Olof
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Antoni, Gunnar
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Synthesis and preclinical evaluation of Ga-68-labeled collagelin analogs for imaging and quantification of fibrosis2014Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 41, nr 9, s. 728-736Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives: Fibrosis affecting functionality of vital organs such as liver, lung, heart, and kidney, is involved in many chronic diseases. Positron emission tomography (PET) would not only provide precise localization and extent of the affected tissue but also allow the accurate quantification of the fibrotic process for the subsequent prognosis. Methods: A cyclic peptide c[CPGRVMHGLHLGDDEGPC] conjugated either to 2-(4,7-bis(2-(tert-butoxy)-2-oxoethyl)-1,4,7-triazonan-1-yl)acetic acid (NOTA(tBu)2) or 4-(4,7-bis(2-(tert-butoxy)-2-oxoethyl)-1,4,7-triazacyclononan-1-yl)-5-(tert-butoxy)-5-oxopentanoic acid (NODAGA(tBu)3) via polyethylene glycol link (PEG2) was synthesized and labeled with Ga-68. Non-specific organ distribution, blood clearance, and excretion were investigated ex vivo in healthy rats. The binding specificity of the radioligands was assessed in vitro using autoradiography on cryosections of dog fibrotic heart tissue. Results: The yield of NOTA-PEG(2)-c[CPGRVMHGLHLGDDEGPC] and NODAGA-PEG(2)-c[CPGRVMHGLHLGDDEGPC] was 56% and 41%, respectively. Non-decay-corrected radiochemical yield was 80 +/- 5% with radiochemical purity of 95 +/- 4%. Pharmacokinetic studies in healthy male Sprague-Dawley rats showed fast blood clearance and renal excretion. Lower uptake in liver, spleen, and kidney was found for [[Ga-68]Ga-NOTA](+1)-PEG(2)-c [CPGRVMHGLHLGDDEGPC] as compared to [[Ga-68]Ga-NODAGA](0)-PEG(2)-c[CPGRVMHGLHLGDDEGPC]. Histologic evaluation of the left ventricle (LV) myocardium from a dog with severe mitral regurgitation (MR), revealed mild to moderate perivascular and subendocardial, and mild diffuse interstitial fibrosis. The tracer binding to the cryosections of the tissue was specific with the equilibrium Kd of 2.3 +/- 0.8 mu M and 2.1 +/- 0.9 mu M, respectively for [Ga-68]Ga-NO2A-Col and [Ga-68]Ga-NODAGA-Col. Conclusions: Two novel peptide based agents for the imaging of fibrosis by PET were developed. Moderation of the biodistribution could be achieved by variation of the charge on the complex moiety of the agents. The combination of the fast clearance from non-target organs as well as organs of interest such as lung, heart, and liver and binding specificity to the target tissue suggests the potential of the analogs for the imaging of fibrosis.

  • 64.
    Velikyan, Irina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för radiologi.
    Eriksson, Barbro
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Lundqvist, Hans
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Klinisk fysiologi.
    Bergström, Mats
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    Imaging biomarkers for diagnosis and quantification with positron emission tomography: assistance to therapy2010Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 37, nr 6, s. 724-724Artikel i tidskrift (Övrigt vetenskapligt)
  • 65.
    Velikyan, Irina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för radiologi.
    Eriksson, Barbro
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Lundqvist, Hans
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Bergström, Mats
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    In vivo binding of [68Ga]-DOTATOC to somatostatin receptors in neuroendocrine tumours — impact of peptide mass2010Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 37, nr 3, s. 265-275Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVES: The aim of this pilot study was to explore the impact of peptide mass on binding of [(68)Ga]-DOTATOC to neuroendocrine tumour somatostatin receptors in vivo using a tracer of variable specific radioactivity (SRA) and to show the logistic feasibility of sequential PET scans in the same patient. MATERIAL AND METHODS: Nine patients with gastroenteropancreatic neuroendocrine tumours were included. Six of them underwent three sequential PET-CT examinations with intravenous injections of [(68)Ga]-DOTATOC proceeded by 0, 50 and 250 or 500 microg of octreotide, administered 10 min before the tracer. Three patients were examined by dynamic and static PET/CT for pharmacokinetic and dosimetric calculations. The [(68)Ga]-DOTATOC synthesis included preconcentration and purification of the generator eluate and microwave heating in a semi-automated in-house procedure. RESULTS: [(68)Ga]-DOTATOC synthesis and quality control were accomplished within 30 min and radiochemical purity was >95%. The tracer accumulation in the tumours varied and depended on the total amount of the administered peptide. In five of six patients, the highest tumour-to-normal tissue ratio was found when 50 microg of octreotide was preadministered. One patient showed a continuously increasing tumour uptake. Dosimetrically, a large variation in organ doses was found (kidney: 0.086-0.168 mSv/MBq; liver: 0.026-0.096 mSv/MBq; spleen: 0.046-0.226 mSv/MBq). The effective dose (0.015, 0.0067 and 0.0042 mSv/MBq) was correlated to the total amount of decays. DISCUSSION: Three sequential PET-CT examinations using (68)Ga-based tracer was carried out in 1 day. The use of high SRA [(68)Ga]-DOTATOC and unlabelled octreotide indicates an optimal mass leading to better image contrast. [(68)Ga]-DOTATOC-PET-CT employing variable SRA may be utilised for accurate quantification of tumour uptake with subsequent dosimetry for personalized therapy management.

  • 66.
    Velikyan, Irina
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för biomedicinsk strålningsvetenskap. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Xu, Hui
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap.
    Nair, Manoj
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap.
    Hall, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Plattformen för preklinisk PET.
    Robust labeling and comparative preclinical characterization of DOTA-TOC and DOTA-TATE2012Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 39, nr 5, s. 628-639Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives: Various radionuclide-labeled somatostatin analogues are used currently for diagnosis and therapy of neuroendocrine tumors. In particular, [Ga-68]Ga-DOTA-TOC is commonly used for diagnosis, while [Lu-177]Lu-DOTA-TATE is used for therapy. With the development of theranostics and personalized medicine where the imaging diagnosis is tailored to the subsequent radiotherapy, it is of paramount importance to investigate the relevance of the ligand exchange. The aim of this study was to compare binding capacity of [Ga-67/68]Ga-DOTA-TOC ([Ga-67/68]Ga-N-(4,7,10-(tris(carboxymethyl)-1,4,7,10-tetraazacyclododecan-1-yl)acetyl-D-Phe-c[Cys-D-Tyr-Trp-Lys-Thr-Cys]-Thr(ol)) and [Ga-67/68]Ga-DOTA-TATE ([Ga-67/68]Ga-N-(4,7, 10-(tris(carboxymethyl)-1,4,7,10-tetraazacyclododecan-1-yl)acetyl-D-Phe-c[Cys-D-Tyr-Trp-Lys-Thr-Cys]-Thr) in vitro in monkey brain cryosections and in vivo in the rat, where, in contrast to transfected cell lines, there is a heterogeneous distribution of somatostatin receptor (SSTR) subtypes. The influence of various production methods of [Ga-68]Ga-DOTA-TOC and [Ga-68]Ga-DOTA-TATE on the biological performance of the tracers was also studied. Material and Methods: [Ga-67]Ga-DOTA-TOC, [Ga-68]Ga-DOTA-TOC, [Ga-67]Ga-DOTA-TATE and [Ga-68]Ga-DOTA-TATE were synthesized including preconcentration and purification of the generator eluate. The binding of the radioligands was assessed in vitro using autoradiography on cryosections of Rhesus monkey brains and in vivo/ex vivo using organ distribution studies in rats. Results and Discussion: The tracer production method was improved in terms of higher robustness, simplification and good manufacturing practice (GMP) relevance. The synthesis variation did not influence the biological performance of the tracers. There was no statistically significant difference observed in the binding of [Ga-67/68]Ga-DOTA-TOC and [Ga-67/68]Ga-DOTA-TATE either in brain cortex in vitro or in rat biodistribution and uptake in SSTR-positive tissues such as pancreas, adrenals and pituitary. The uptake in these organs was precluded by the excess of octreotide (Sandostatin). The 10-fold higher affinity to SSTR2 of DOTA-TATE as compared to DOTA-TOC known from studies in transfected cells was reflected in a slightly more intense binding of [Ga-67/68]Ga-DOTA-TATE than of [Ga-67/68]Ga-DOTA-TOC in the monkey brain sections in vitro, but not in vivo in the rat. Conclusion: A robust Ga-68-labeling method was introduced. The difference in the uptake of [Ga-67/68]Ga-DOTA-TOC and [Ga-67/68]Ga-DOTA-TATE in SSTR2-positive organs was not statistically significant either in vitro in tissue studies or in vivo/ex vivo in rat experiments. The results indicate that the more complex environment in vitro and in vivo diminishes the difference observed in transfected cell line binding. 

  • 67.
    Verbeek, Joost
    et al.
    VU University Medical Center Amsterdam.
    Syvänen, Stina
    Leiden University.
    Schuit, Robert C
    Eriksson, Jonas
    VU University Medical Center Amsterdam.
    de Lange, Elizabeth C
    Windhorst, Albert D
    Luurtsema, Gert
    Lammertsma, Adriaan A
    Synthesis and preclinical evaluation of [11C]D617, a metabolite of (R)-[11C]verapamil.2012Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 39, nr 4, s. 530-9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVES: (R)-[(11)C]verapamil is widely used as a positron emission tomography (PET) tracer to evaluate P-glycoprotein (P-gp) functionality at the blood-brain barrier in man. A disadvantage of (R)-[(11)C]verapamil is the fact that its main metabolite, [(11)C]D617, also enters the brain. For quantitative analysis of (R)-[(11)C]verapamil data, it has been assumed that the cerebral kinetics of (R)-[(11)C]verapamil and [(11)C]D617 are the same. The aim of the present study was to investigate whether the cerebral kinetics of (R)-[(11)C]verapamil and [(11)C]D617 are indeed similar and, if so, whether [(11)C]D617 itself could serve as an alternative PET tracer for P-gp.

    METHODS: [(11)C]D617 was synthesized and its ex vivo biodistribution was investigated in male rats at four time points following intravenous administration of [(11)C]D617 (50 MBq) without (n=4) or with (n=4) pretreatment with the P-gp inhibitor tariquidar (15 mg·kg(-1), intraperitoneally). Brain distribution was further assessed using consecutive PET scans (n=8) before and after pretreatment with tariquidar (15 mg·kg(-1), intravenously), as well as metabolite analysis (n=4).

    RESULTS: The precursor for the radiosynthesis of [(11)C]D617, 5-amino-2-(3,4-dimethoxy-phenyl)-2-isopropyl-pentanitrile (desmethyl D617), was synthesized in 41% overall yield. [(11)C]D617 was synthesized in 58%-77% decay-corrected yield with a radiochemical purity of ≥99%. The homogeneously distributed cerebral volume of distribution (V(T)) of [(11)C]D617 was 1.1, and this increased 2.4-fold after tariquidar pretreatment.

    CONCLUSION: V(T) of [(11)C]D617 was comparable to that of (R)-[(11)C]verapamil, but its increase after tariquidar pretreatment was substantially lower. Hence, (R)-[(11)C]verapamil and [(11)C]D617 do not show similar brain kinetics after inhibition of P-gp with tariquidar.

  • 68. Westerberg, Göran
    et al.
    Bergström, Mats
    Gustafson, Stefan
    Lindqvist, Ulla
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för radiologi.
    Långström, Bengt
    Labelling of polysaccharides using [11C]cyanogen bromide: In vivo and in vitro evaluation of 11C-hyaluronan uptake kinetics1995Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 22, nr 2, s. 251-256Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A method for the 11C-labelling of polysaccharides in high specific radioactivity is described. Dextran and hyaluronan were treated with [11C]cyanogen bromide in aqueous solution at pH 11.5 to give 30-47% radiochemical yields with higher than 98% radiochemical purity in synthesis times of 24-26 min counted from the end of bombardment. Specific radioactivities at the end of synthesis ranged from 0.12 to 3.1 Ci/mumol. The biodistribution kinetics of [11C]hyaluronan injected intravenously was studied in rats by means of positron emission tomography, showing a rapid and displaceable uptake in liver. Uptake and displacement of [11C]hyaluronan was also demonstrated in cultured rat liver endothelial cells.

  • 69.
    Winberg, Karl Johan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi, Organisk kemi II.
    Persson, Mikael
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för biomedicinsk strålningsvetenskap.
    Malmström, Per-Uno
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper.
    Sjöberg, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi, Organisk kemi II.
    Tolmachev, Vladimir
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi.
    Radiobromination of anti-HER2/neu/ErbB-2 monoclonal antibody using the p-isothiocyanatobenzene derivative of the [76Br]undecahydro-bromo-7,8-dicarba-nido-undecaborate(1-) ion2004Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 31, nr 4, s. 425-33Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The monoclonal humanized anti-HER2 antibody trastuzumab was radiolabeled with the positron emitter (76)Br (T(1/2) =16.2 h). Indirect labeling was performed using the p-isothiocyanatobenzene derivative of the [(76)Br]undecahydro-bromo-7,8-dicarba-nido-undecaborate(1-) ((76)Br-NBI) as a precursor molecule. (76)Br-NBI was prepared by bromination of the 7-(p-isothiocyanato-phenyl)dodecahydro-7,8-dicarba-nido-undecaborate(1-) ion (NBI) with a yield of 93-95% using Chloramine-T (CAT) as an oxidant. Coupling of radiobrominated NBI to antibody was performed without intermediate purification, in an "one pot" reaction. An overall labeling yield of 55.7 +/- 4.8% (mean +/- maximum error) was achieved when 300 microg of antibody was labeled. The label was stable in vitro in physiological and denaturing conditions. In a cell binding test, trastuzumab remained immunoreactive after labeling.

  • 70. Wu, F
    et al.
    Lendvai, G
    Yngve, U
    Eriksson, B
    Langstrom, B
    Bergstrom, M
    Hybridisation of [Br-76]-labelled antisense oligonucleotides to Chromogranin A mRNA verified by RT-PCR2004Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 31, nr 8, s. 1073-1078Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Methods have been developed to label oligonucleotides (ODNs) in the 5'-position with Br-76 via a prosthetic group on a hexylamino-linker. The purpose of the study was to explore whether the labelling procedure would prevent specific hybridisation by using reverse transcription-polymerase chain reaction (RT-PCR) followed by sequencing of the PCR product. Antisense ODNs (30 mer, specific for rat Chromogranin A [CgA] mRNA) with phosphodiester (O-ODN) or phosphothiciate (S-ODN) backbone, either unlabelled or labelled with Br-76, served as one of the primers in individual PCR reactions. Using O-ODN as a primer, irrespective of being labelled or not, a selected 225-bp PCR fragment was successfully amplified. However, no amplification was obtained using S-ODN as a primer. The proper PCR products were only detected in the sample prepared from the adrenal gland, but not in that from the heart, liver or kidney. Autoradiographic recording of the gel, after gel electrophoresis, revealed radioactive signals corresponding to the amplified PCR products. The sequence of the PCR product matched the rat CgA mRNA sequence obtained from the EMBL database. RT-PCR is an attractive method to identify the selective binding of modified ODNs to target mRNA. This method confirmed that the labelling with Br-76 did not change the hybridisation ability of antisense O-ODN. (C) 2004 Elsevier Inc. All rights reserved.

  • 71.
    Örlefors, Håkan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Fasth, Karl-Johan
    Öberg, Kjell
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Långström, Bengt
    Eriksson, Barbro
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Bergström, Mats
    Demonstration of high monoamineoxidase-A levels in neuroendocrine gastroenteropancreatic tumors in vitro and in vivo: tumor visualization using positron emission tomography with 11C-harmine2003Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 30, nr 6, s. 669-679Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background and Aims: A majority of neuroendocrine gastroenteropancreatic (GEP) tumors can be detected by conventional radiological methods and scintigraphic techniques. Still there are problems to visualize small tumor lesions and non-functioning tumors. The aim of this study was to investigate some of the monoamine processing pathways of neuroendocrine GEP-tumors and try to find a new tracer substance for in vivo characterization and visualization by Positron Emission Tomography (PET).

    Subjects and Methods: Autoradiography of tumor sections from 8 midgut carcinoids (MGC) and 8 endocrine pancreatic tumors (EPT) was performed with C-11-labeled tracers for serotonin and dopamine transporters, serotonin HT2A-, dopamine D1- and muscarinic receptors and for monoamine oxidase A (MAO-A). The in vitro results initiated PET studies with C-11-Harmine in 4 patients with MGC and 7 patients with EPT (one insulinoma, two glucagonomas and four non-functioning EPT).

    Results: The MAO-A-ligand Harmine expressed specific in vitro binding of 87 +/- 21% for MGC and 125 +/- 50% for EPT, compared to reference tissue (rat brain, 100%). All other substances showed relatively low specific binding. C-11-harmine-PET could visualize tumors in all patients. The mean standardized uptake value (SUV) for MGC was 7.5 +/- 3.9 and for EPT 12.9 +/- 2.7, whereas the SUV of normal liver, intestine and pancreas were 3.1 +/- 0.5, 3.4 +/- 1.2 and 8.9 +/- 3.0 respectively. Conclusions: This study demonstrates in vitro and in vivo that neuroendocrine GEP-tumors are characterized by a high MAO-A-expression, thereby adding to the similarities of neuronal and neuroendocrine tissue. It also indicates a possible application for C-11-harmine as a new PET-tracer for neuroendocrine GEP-tumors with the potential to visualize also non-functioning EPT's.

12 51 - 71 av 71
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf