In vivo irradiation

Lloyd, D.C. Hie problems of interpreting aberration yields induced by in vivo irradiation of lymphocytes, pp. 77-88. In H.J. Evans and D.C. Lloyd, Eds. Mutagen-induced Chromosome Damage in Man. New Haven Yale Univ. Press, 1978. 

Activation analysis can be used for determination of trace elements, in particular heavy metals and essential elements, in various parts or organs, respectively, of plants or animals and man. Making use of the high sensitivity of activation analysis, small samples of the order of several milligrams taken from selected places give information about the concentration of the elements of interest. The results of activation analysis of trace elements also allow conclusions with respect to diseases or malfunctions and are valuable aids to diagnosis. Examples are the determination of Se in man or of trace element concentrations in bones or other parts, with respect to the sufficient supply of essential elements and metabolism. In vivo irradiation has also been proposed. 

In an effort to mimic the conditions encountered in in vivo irradiation in the epidermis, the irradiation of 7-dehydrocholesterol (157) in various ordered lipid multilayers has been studied. The results (Table 4 and Scheme 13) clearly show... 

A principal appHcation for photomedicine is the photodynamic treatment of cancer. Photochemical and clinical aspects of this topic have been reviewed (10,11). Direct irradiation of tumors coupled with adininistration of a sensitizer is used to effect necrosis of the malignancy. In this process, an excited state sensitizer interacts with dissolved in vivo to effect conversion of the oxygen from its triplet ground state to an excited singlet state, which is highly cytotoxic. In principle, excited sensitizers in either the singlet or the triplet state can effect this conversion of molecular oxygen (8). In... 

Similar to pure polyglycoHc acid and pure polylactic acid, the 90 10 glycolide lactide copolymer is also weakened by gamma irradiation. The normal in vivo absorption time of about 70 days for fibrous material can be decreased to less than about 28 days by simple exposure to gamma radiation in excess of 50 kGy (5 Mrads) (35). 

Basic FGF can also stimulate murine hemopoietic progenitors in vitro. It is synergistic with hemopoietic growth factors such as GM-CSF, EPO, and Meg-CSF and has radioprotective activity in vivo, increasing the number of day-9 and day-12 CFU-S from lethaUy irradiated animals (195). Furthermore, b-FGF combiaed with GM-CSF protects against the killing of murine and human CFU-GM exposed to radiation in vitro (195). 

In vitro absorption-spectrophotometry techniques are available to assess a sunscreen s efficacy, but the preferred methods are in vivo procedures in which a small body site is irradiated with the desired wavelengths for different periods in the presence or absence of a uv protectant. Procedures vary from country to country to determine the incremental timing of the exposure that ultimately allows quantification via sun protective factor (SPE). In the United States, sunscreen preparations are considered OTC dmg products, and the SPE must be specified (54). Even in countries that do not identify these products as dmgs, SPE labeling has become customary. 

Recently, 202 and 203 were found to significantly reduce the mutation frequency induced by BaP in vivo as well (00UP3). Previously, flie same group had pointed out that some genotoxic effects could result from UV irradiation of tryptophan, but this had not been attributed to lipophilic substances like 202 and 203 (94MI5). 

Experiments in rats (38) have shown that y irradiation decreases the inherent viscosity of lactide/glycolide copolymers and increases the biodegradation rate. The in vivo lifetime of a 92 8 DL-lactide/ glycolide copolymer was decreased from about 40 weeks to about 30 weeks after treatment with 2 Mrad of y irradiation. 

Simple DTPA chelates labeled with 90Y are not sufficiently stable in vivo. This instability leads to accretion of the metal ion in bone such unwanted accumulation results in undesirable irradiation of the bone marrow.90... 

By using an in vitro UV-crosslinking approach, bacteria-purified recombinant CPEB3 has been demonstrated to interact with the 2> UTR of GluR2 mRNA. To test whether this interaction occurs in vivo, hippocampal neuron cultures are ultraviolet (UV)-irradiated, homogenized, and immunoprecipitated with CPEB3 IgG or nonspecific IgG (Huang et al, 2006). Three plates of 2- to 3-week-old cultured neurons ( 6—8 million... 

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