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A F Fuciarelli

Publications and source records attributed to A F Fuciarelli.

25 records · Page 2Linked to original sources
PubMed1987

Fluorescence immunohistochemical detection of hypoxic cells in spheroids and tumours.

Polyclonal antibodies have been raised in rabbits to a haemocyanin adduct of a reductively-activated, fluorinated analogue of misonidazole. Fluorescence immunohistochemical studies show that the polyclonal antibodies bind to spheroid sections and tumour sections in patterns similar to those revealed by autoradiographic studies with a tritium-labelled derivative of the fluorinated misonidazole analogue.

Animals↗
PubMed1987

Interaction of nitroaromatic radiosensitizers with irradiated polyadenylic acid as measured by an indirect immunochemical assay with specificity for the 8,5'-cycloadenosine moiety.

The relative reactivity of a series of nitroaromatic radiosensitizers toward the C(5') radical intermediate leading to 8,5'-cycloadenosine formation in deoxygenated solutions of irradiated polyadenylic acid (poly A) was assessed using standard competition kinetic analysis. Formation of 8,5'-cycloadenosine was assayed by an indirect, competitive, enzyme-linked immunosorbent assay (ELISA) described in an earlier report. In the absence of oxygen, the nitroaromatics inhibit 8,5'-cyclonucleoside formation in a way which generally increases with radiosensitizer electron affinity. Although hydroxyl radical scavenging by the nitroaromatics may account for a relatively small decrease in 8,5'-cyclonucleoside formation, the data suggest that oxidation of the C(5') radical intermediate is the more plausible explanation for the decreased yield of the 8,5'-cyclonucleoside with increasing nitroaromatic electron affinity.

Adenosine↗
PubMed1987

Intramolecular cyclization in irradiated nucleic acids: correlation between high-performance liquid chromatography and an immunochemical assay for 8,5'-cycloadenosine in irradiated poly(A).

A correlation between high-performance liquid chromatography (HPLC) analysis and an in situ enzyme-linked immunosorbent assay (ELISA) for 8,5'-cycloadenosine formation in irradiated poly(A) has been established. The correlation shows that the ELISA precisely reflects changes in the combined yield of R- and S-8,5'-cycloadenosine but that a correction factor must be applied to the ELISA values for accuracy. The HPLC analysis reveals that the intramolecular cyclization proceeds stereoselectively in irradiated poly(A) to preferentially produce the R isomer at pH 7.0 which is similar to the result for irradiated adenosine but in contrast to the result for 5'-AMP where the S isomer predominates at neutral pH. The HPLC analysis shows that two events originating in hydroxyl radical attack at the sugar phosphate backbone in poly(A); that is, adenine release and 8,5'-cycloadenosine formation have somewhat different dose-yield responses. The formation of 8-hydroxyadenosine was detected in the HPLC chromatograms of poly(A) irradiated under N2O at neutral pH, and the yield of this compound was similar to the yield observed in 5'-AMP or adenosine irradiated under similar conditions.

Adenosine↗
PubMed1986

Stereoselective intramolecular cyclization in irradiated nucleic acids: R- and S-8,5'-cycloadenosine in polyadenylic acid.

The yields of R- and S-8,5'-cycloadenosines have been measured in poly A irradiated with gamma rays in the absence of oxygen. High performance liquid chromatographic analysis of the nucleoside analogues obtained by hydrolysis of the irradiated poly A shows that the R isomer predominates to the extent of 2.5-fold at doses of ionizing radiation in the range of 0-400 Gy.

Adenosine↗
PubMed1985

An immunochemical probe for 8,5'-cycloadenosine-5'-monophosphate and its deoxy analog in irradiated nucleic acids.

Polyclonal antisera specific for 8,5'-cycloadenosine-5'-monophosphate (8,5'-cyclo-AMP) or its deoxy analog (8,5'-cyclo-dAMP) were elicited by immunizing rabbits with a conjugate prepared by the method of Johnston et al. [Biochemistry 22, 3453-3460 (1983)]. A competitive enzyme-linked immunosorbent assay (ELISA) was developed and used to detect the formation of these products in irradiated solutions of polyadenylic acid [poly(A)] or DNA which were saturated with nitrous oxide, nitrogen, or oxygen. The 8,5'-cyclo-AMP or 8,5'-cyclo-dAMP moieties could be detected in poly(A) at 1.0 krad and in native DNA at 10 krad, respectively. The yield of 8,5'-cyclo-dAMP was found to be two to three times higher in irradiated double-stranded DNA than in single-stranded DNA. The hydroxyl radical appears to initiate 8,5'-cyclonucleotide formation in irradiated nucleic acids, as demonstrated by the inhibition of 8,5'-cyclo-AMP formation in irradiated poly(A) by dimethyl sulfoxide. However, irradiation under nitrous oxide, particularly at low doses, does not lead to the expected increases in the yield of the 8,5'-cyclonucleotide.

Adenosine Monophosphate↗
PubMedDate not supplied

Identification and characterization of radiation damaged products of monophosphate nucleosides by on-line capillary isotachophoresis-electrospray ionization mass spectrometry.

Analysis of trace levels of DNA damage as a biomarker of human exposure to radiation levels represents a significant challenge. Capillary isotachophoresis (CITP) is well suited for this application due to its high separation efficiency, large sample loading capacity, and relative ease of interfacing with highly specific and sensitive mass spectrometric detectors. This study describes the use of reversed anionic CITP coupled on-line with electrospray ionization-mass spectrometry (ESI-MS) for the identification and characterization of small quantities of radiation induced damage to deoxynucleotide monophosphates. CITP with ESI-tandem MS also provides structural information on the nature of the damage in addition to the molecular weight. This approach has the attraction of allowing the direct on-line determination of damaged nucleotides, as well as the free bases and nucleosides, and avoids the need for sample hydrolysis and/or derivatization.

Biomarkers↗