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11.
Erich Stoelben Holger Harpering Joerg Haberstroh Antonio di Filippo Eckhard Wellens 《European journal of cardio-thoracic surgery》2003,23(1):15-20
INTRODUCTION: The successful use of cryopreserved tracheal allografts in canine models suggests their use in humans. The grade of genetic difference, the mechanism of revascularisation and the method of cryopreservation are not clearly defined. The purpose of our study was to investigate the rejection of tracheal transplants in a standardised heterotopic rat model using different forms of cryopreservation. METHODS: Tracheae from Brown Norway rats were implanted into the omentum from Brown Norway rats or Lewis rats. We transplanted fresh isografts or allografts and pretreated isografts or allografts. Cryopreservation was performed in a medium containing 10% dimethyl sulphoxide at -80 degrees C for 28 days (I) or -196 degrees C for 84 days (II) or without medium at -80 degrees C for 28 days (III). The transplants were excised after 7 and 21 days, respectively. RESULTS: Histological examinations revealed normal structure and function of isografts after 21 days. In the cryopreserved isograft, the epithelium had disappeared and the tracheal lumen was partially obstructed by a non-compact fibrous tissue. In the fresh allografts, the epithelium was replaced by aggressive fibrous tissue, infiltrating the membranous part of the trachea and occluding the tracheal lumen. The cartilage was vital without any sign of rejection. In the cryopreserved allografts, the tracheal lumen was obstructed by dense fibrous tissue with an inflammatory reaction. The cartilage of cryopreserved allografts (II) and (III) had lost the nuclei corresponding to non-vital tissue. Only in the cryopreserved allografts (I) did we find nodular regeneration at the edges of the cartilaginous bow. CONCLUSIONS: The heterotopic transplantation model allows the study of the mechanisms leading to tracheal obstruction. Cryopreservation was found to have no clear advantage in reducing transplant immunogenicity. Cryopreservation leads to significant damage to the cartilage, the intensity of which is dependent on the mode of cryopreservation. 相似文献
12.
Stefanie Klaffke Andrea A Kuhn Michail Plotkin Holger Amthauer Daniel Harnack Roland Felix Andreas Kupsch 《Movement disorders》2006,21(10):1724-1727
Alterations in presynaptic and postsynaptic dopaminergic system and cerebral glucose metabolism in corticobasal degeneration (CBD) were assessed to evaluate the potential usefulness of different imaging methods for CBD. (123)I-FP-CIT/(123)I-beta-CIT SPECT and (123)I-IBZM SPECT as well as (18)F-FDG PET were performed in eight CBD patients. Decreased presynaptic dopamine transporter binding was found in all CBD patients while D2 receptor binding was reduced in only one patient. (18)F-FDG PET displayed a contralateral hypometabolism in cortical and subcortical areas in seven out of eight patients. Our results demonstrate that glucose metabolism and DAT are reduced, while D2 receptors may be frequently preserved in CBD. 相似文献
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Christian Foged Christer Halldin Christian Loc’h Bernard Mazière Stefan Pauli Mariannick Maziére Holger C. Hansen Tetsuya Suhara Carl-Gunnar Swahn Per Karlsson Lars Farde 《European journal of nuclear medicine and molecular imaging》1997,24(10):1261-1267
NNC 13-8241 has recently been labelled with iodine-123 and developed as a metabolically stable benzodiazepine receptor ligand
for single-photon emission computed tomography (SPECT) in monkeys and man. NNC 13-8199 is a bromo-analogue of NNC 13-8241.
This partial agonist binds selectively and with subnanomolar affinity to the benzodiazepine receptors. We prepared 76Br labelled NNC 13-8199 from the trimethyltin precursor by the chloramine-T method. Carbon-11 labelled NNC 13-8199 was synthesised
by N-alkylation of the nitrogen of the amide group with [11C]methyl iodide. Positron emission tomography (PET) examination with the two radioligands in monkeys demonstrated a high uptake
of radioactivity in the occipital, temporal and frontal cortex. In the study with [76Br]NNC 13-8199, the monkey brain uptake continued to increase until the time of displacement with flumazenil at 215 min after
injection. For both radioligands the radioactivity in the cortical brain regions was markedly reduced after displacement with
flumazenil. More than 98% of the radioactivity in monkey plasma represented unchanged radioligand 40 min after injection.
The low degree of metabolism indicates that NNC 13-8199 is metabolically much more stable than hitherto developed PET radioligands
for imaging of benzodiazepine receptors in the primate brain. [76Br]NNC 13-8199 has potential as a radioligand in human PET studies using models where a slow metabolism is an advantage.
Received 19 April and in revised form 10 June 1997 相似文献
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Michael Krause Agns Rouleau Holger Stark Peter Luger Monique Garbarg Jean-Charles Schwartz Walter Schunack 《Archiv der Pharmazie》1996,329(4):209-215
The therapeutic value of histamine H3-receptor ligands is under current investigation. On the basis of recently described diaryl imine prodrugs of the histamine H3-receptor agonist (R)-α-methyl-histamine ( 1 ) a series of new azomethine prodrugs containing five- and six-membered heterocycles were synthesized and tested for their in vitro hydrolysis rates and in vitro activity after oral application. It was found that electron-deficient six-membered heterocycles drastically destabilized the imine double bond so that these prodrugs decomposed unsuitably fast. On the contrary, prodrugs containing five-membered heterocycles appeared to be highly effective for the CNS delivery of 1 , and a remarkable correlation between chemical structure and pharmacokinetic profile was observed. Particularly (R)-4-fluoro-2-[[N-[1-(1H-imidazol-4-yl)-2-propyl]imino](1H-pyrrol-2-yl)methyl]phenol ( 8c ), the 2-furanyl analogue 8d , and its 3-furanyl isomer 8e proved to be equipotent to the most potent of recently described halogenated diaryl imine prodrugs of 1. However, in contrast to any other azomethine prodrug, 8c exhibited an incomparably long lasting delivery of 1 in the CNS and can thus be regarded as a ‘retard’ prodrug. Assuming that a therapeutic indication of histamine H3-receptor agonists will soon be established, these highly potent heteroarylphenyl azomethine prodrugs, which already serve as valuable pharmacological tools, may also become potential drugs in clinical use. 相似文献
19.
Automated extraction of genomic DNA from medically important yeast species and filamentous fungi by using the MagNA Pure LC system 总被引:5,自引:0,他引:5 下载免费PDF全文
Loeffler J Schmidt K Hebart H Schumacher U Einsele H 《Journal of clinical microbiology》2002,40(6):2240-2243
A fully automated assay was established for the extraction of DNA from clinically important fungi by using the MagNA Pure LC instrument. The test was evaluated by DNA isolation from 23 species of yeast and filamentous fungi and by extractions (n = 28) of serially diluted Aspergillus fumigatus conidia (10(5) to 0 CFU/ml). Additionally, DNA from 67 clinical specimens was extracted and compared to the manual protocol. The detection limit of the MagNA Pure LC assay of 10 CFU corresponded to the sensitivity when DNA was extracted manually; in 9 of 28 runs, we could achieve a higher sensitivity of 1 CFU/ml blood, which was found to be significant (p 相似文献
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