Disease relevance of cobalt

• The concentration of cobalt-57 (57Co)-labeled bleomycin delivered to three brain metastases and to their tumors of origin in the lungs was measured using a single-photon emission computerized tomography technique [1].
• The value of Cobalt-57 bleomycin (57Co-BLM) scintigraphy in the detection of lymph node metastases in the hilum and mediastinum was investigated in 132 patients with peripherally located lung cancer [2].
• Cobalt-57 SPET in relapsing-progressive multiple sclerosis: a pilot study [3].
• Using 15 micrometers Cobalt-57 microspheres for studying salivary adenocarcinoma implants in DA rat livers, these experiments have demonstrated a constant blood flow in the tumor periphery of 3.9 times that within the normal hepatic parenchyma, regardless of tumor size [4].
• Concentrations of bleomycin labeled with cobalt 57 (Co-bleo) over time were measured in vivo in 17 patients with 32 sites of lymphoma and 18 patients with lung tumors after administration of the same dose of bleomycin [5].

High impact information on cobalt

• Using oriented epitaxial Co2+: ZnO films grown by chemical vapor deposition, kinetics measurements demonstrate a direct correlation between the oxidative quenching of ferromagnetism and the diffusion and oxidation of interstitial zinc [6].
• In a separate series of experiments, the Na+ flux across the blood-brain barrier was studied by injecting 22NaCl together with an intravascular reference (cobalt-57-labeled microspheres 15 microns in diameter) into the ischemic area [7].
• Measurement of total-body cobalt-57 vitamin B12 absorption with a gamma camera [8].
• Central venous pressure line localization with a cobalt-57 marker system [9].
• For two different murine monoclonal antibodies, the average chelator content obtained by terbium fluorescence titration correlated closely with that measured by the cobalt-57 binding assay [10].

Biological context of cobalt

• In vivo quantitative measurements of the pharmacokinetics of technetium-99m (99mTc) glucoheptonate, cobalt-57 (57Co) bleomycin and platinum-195m (195mPt) cisplatin in human tumors in vivo indicates that, in contrast with tumor models in animals, there is a marked variability in drug delivery even in tumors with the same histology [11].
• We used single photon emission tomography (SPET) and cobalt-57 (57Co) as a calcium (Ca) analogue to visualize brain tissue damage, based on the fact that Ca influx occurs in both cell death and T-lymphocyte activation in MS [3].
• We evaluated the attenuation of the 122 keV gamma ray of cobalt-57 across the thorax of anesthetized dogs as a method for following the time course of lung water changes in acute pulmonary edema induced by either increased microvascular permeability or increased microvascular hydrostatic pressure [12].

Anatomical context of cobalt

• The distribution of tibial blood flow was measured by injecting approximately (600-1000) x 10(3) 15 mu microspheres, labelled with either tin-113 (113Sn) or cobalt-57 (57Co) into femoral arteries of five mature greyhounds [13].
• In vitro, maximal noncytotoxic doses of As2O3, Co, WC, or WC-Co did not significantly affect the production of these mediators by rat alveolar macrophages [14].
• We have attempted to correlate the incidence of measureable uptake of cobalt 57 tagged bleomycin by primary squamous cell carcinoma and metastatic cervical lymph nodes [15].
• Cobalt-57 as a SPET tracer in the visualization of ischaemic brain damage in patients with middle cerebral artery stroke [16].

Associations of cobalt with other chemical compounds

• When Cobalt-57 microspheres were given before oleic acid, Cobalt-57 activity was marginally lower in the outer layer compared with the middle and inner layers [17].
• The radiochemical purity of the cobalt-57 complex of bleomycin could be enhanced by adjusting the pH of the final product to a value between 5 and 6 [18].

Analytical, diagnostic and therapeutic context of cobalt

• Uniformity correction for SPECT using a mapped cobalt-57 sheet source [19].
• This inhibitor coordinates the metal center through four interactions as follows: (i) ligation of the N-terminal (3R)-nitrogen to Co2, (ii, iii) bridging coordination of the (2S)-hydroxyl group, and (iv) terminal ligation to Co1 by the keto oxygen of the pseudo-peptide linkage [20].

References