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  • 1
    Electronic Resource
    Electronic Resource
    Introducing fluorine-18 fluoromisonidazole positron emission tomography for the localisation and quantification of pig liver hypoxia (1999)
    Springer
    European journal of nuclear medicine 26 (1999), S. 95-109 
    Details
    ISSN: 1619-7089
    Keywords: Key words: Liver cell hypoxia ; Nitroimidazole imaging ; Fluorine-18 fluoromisonidazole ; Positron emission tomography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. Fluorine-18 labelled fluoromisonidazole ([18F]FMISO) has been shown to accumulate in hypoxic tissue in inverse proportion to tissue oxygenation. In order to evaluate the potential of [18F]FMISO as a possible positron emission tomography (PET) tracer for imaging of liver tissue hypoxia, we measured the [18F]FMISO uptake in 13 domestic pigs using dynamic PET scanning. Hypoxia was induced by segmental arterial hepatic occlusion. During the experimental procedure the fractional concentration of inspired oxygen (FiO2) was set to 0.67 in group A (n=6) and to 0.21 in group B (n=7) animals. Before and after arterial occlusion, the partial pressure of O2 in tissue (TPO2) and the arterial blood flow were determined in normal flow and flow-impaired liver segments. Standardised uptake values [SUV=kBq tissue (in g) / body weight (in kg) × injected dose (in kBq)] for [18F]FMISO were calculated from PET images obtained 3 hours after injection of about 10 MBq/kg body weight [18F]FMISO. Immediately before PET scanning, the mean arterial blood flow was significantly decreased in arterially occluded segments [group A: 0.41 (0.32–0.52); group B: 0.24 (0.16–0.33) ml min–1 g–1] compared with normal flow segments [group A: 1.05 (0.76–1.46); group B: 1.14 (0.83–1.57) ml min–1 g–1; geometric mean (95% confidence limits); P〈0.001 for both groups]. After PET scanning, the TPO2 of occluded segments (group A: 5.1 (4.1–6.4); group B: 3.5 (2.6–4.9) mmHg] was significantly decreased compared with normal flow segments [group A: 26.4 (21.2–33.0); group B: 18.2 (13.3–25.1) mmHg; P〈0.001 for both groups]. During the 3-h PET scan, the mean [18F]FMISO SUV determined in occluded segments increased significantly to 3.84 (3.12–4.72) in group A and 5.7 (4.71–6.9) in group B, while the SUV remained unchanged in corresponding normal liver tissue [group A: 1.4 (1.14–1.71); group B: 1.31 (1.09–1.57); P〈0.001 for both groups]. Regardless of ventilation conditions, a significant inverse exponential relationship was found between the TPO2 and the [18F]FMISO SUV (r 2=0.88, P〈0.001). Our results suggest that because tracer delivery to hypoxic tissues was maintained by the portal circulation, the [18F]FMISO accumulation in the liver was found to be directly related to the severity of tissue hypoxia. Thus, [18F]FMISO PET allows in vivo quantification of pig liver hypoxia using simple SUV analysis as long as tracer delivery is not critically reduced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002590050365
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  • 2
    Electronic Resource
    Electronic Resource
    Allogenic bone graft viability after hip revision arthroplasty assessed by dynamic [18F]fluoride ion positron emission tomography (1999)
    Springer
    European journal of nuclear medicine 26 (1999), S. 615-624 
    Details
    ISSN: 1619-7089
    Keywords: Key words: Fluorine-18 ; Bone graft viability ; Hip revision arthroplasty ; Positron emission tomography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. The biological fate of allogenic bone grafts in the acetabular cavity and their metabolic activity after acetabular augmentation is uncertain but is most important for the stability of hip implants after hip revision arthroplasty. The aim of this study was to quantify regional bone metabolism after hip replacement operations. Dynamic [18F]fluoride ion positron emission tomography (PET) was used to investigate the metabolic activity of acetabular allogenic bone grafts and genuine bone, either 3–6 weeks (short-term group, n = 9) or 5 months to 9 years (long-term group, n = 10) after hip revision arthroplasty. Applying a three-compartment model, the fluoride influx constant was calculated from individually fitted rate constants (K nlf) and by Patlak graphical analysis (K pat). The results were compared with genuine cancellous and cortical acetabular bone of contralateral hips without surgical trauma (n = 7). In genuine cortical bone, K nlf was significantly increased in short- (+140.9%) and long-term (+100.0%) groups compared with contralateral hips. Allogenic bone grafts were characterised by a significantly increased K nlf in the short-term group (+190.9%) compared with contralateral hips, but decreased almost to the baseline levels of contralateral hips (+45.5%) in the long-term. Values of K nlf cor-related with the rate constant K 1 in genuine (r = 0.89, P〈0.001) and allogenic bone regions (r = 0.79, P〈0.001), indicating a coupling between bone blood flow and bone metabolism in genuine bone as well as allogenic bone grafts. K pat values were highly correlated with K nlf measurements in all regions. In conclusion, [18F]fluoride ion PET revealed the presence of an increased host bone formation in allogenic bone grafts early after hip revision arthroplasty. In contrast to genuine cortical bone, allogenic bone graft metabolism decreased over time, possibly due to a reduced ability to respond to the same extent as genuine bone to elevated metabolic demands after surgery.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002590050429
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  • 3
    Electronic Resource
    Electronic Resource
    Compounds of Phosphorus with Silicon and AluminumDedicated to Prof. W. Klemm on the occasion of his 70th birthday (1966)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 5 (1966), S. 53-57 
    Details
    ISSN: 0570-0833
    Keywords: Aluminum ; Phosphorus ; Silicon ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The formation and properties of silicon-phosphorus and aluminum-phosphorus compounds are described. Silylphosphines are decomposed solvolytically by H2O, C2H5OH, NH3, hydrogen halides, C2H5I, and boron halides at the Si—P bond; decomposition may be preceded by formation of an addition compound. Extensive side reactions during the reaction of halogenosilanes with LiPEt2The following abbreviations are used in this paper: Et = C2H5; Me = CH3; M = alkali metal (formation of Et2P—PEt2, HPEt2, Si-rich residues) are due to an excess of LiPEt2 in the reaction mixture. The reaction of LiPEt2 with AlCl3, AlHCl2, and AlH2Cl leads to definite aluminum-phosphorus compounds if only one PEt2 group is present per Al atom, e.g. in (Cl2Al-PEt2)3, or if salts such as Li[Al(PEt2)4] and Li[AlH2(PEt2)2] can be formed with an excess of LiPEt2.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196600531
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