A DNA radioimmunoassay, sensitive in the range 25-1000 ng, has been developed to measure gastric mucosal cell loss. Validity of the assay was based on antibody specificity, absence of interference from gastric contents, parallel tracer displacement by dilutions of gastric and standard DNA, and crossover with colorimetric assay. With this assay, gastric DNA shedding was examined in two animal species and man. In the guinea-pig stomach, DNA loss was 20-100 micrograms/h and in the canine Pavlov pouch, 260-580 micrograms/h. In the canine Pavlov pouch stimulation of acid secretion by histamine and exposure to exogenous acid increased DNA output. In the normal human stomach DNA loss was 544 +/- 175 micrograms/h and in duodenal ulcer patients, 649 +/- 225 micrograms/h. DNA radioimmunoassay provides a sensitive and reproducible measure of cell exfoliation from the stomach and may be a useful tool for studying aspects of gastric mucosal defence.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1042/cs0660701 | DOI Listing |
Eur J Nutr
March 2024
Infection and Cancer Group, School of Medicine, Universidad de Antioquia, Carrera 51D No 62-29, 050010, Medellín, Colombia.
Purpose: To our knowledge, there are very few studies evaluating if the levels of folate modify the risk of cervical intraepithelial neoplasia grade 2 and higher (CIN2+ and CIN3+) associated with the levels of HPV genome methylation, two cofactors related to single carbon metabolism and independently associated with cervical cancer in previous studies. We conducted a case-control study nested in a three-arm randomized clinical pragmatic trial (ASCUS-COL trial) to evaluate the risk of CIN3+ associated with methylation levels according to serum folate concentrations.
Methods: Cases (n = 155) were women with histologically confirmed CIN2+ (113 CIN2, 38 CIN3, and 4 SCC) and controls were age and follow-up time at diagnosis-matched women with histologically confirmed ≤ CIN1 (n = 155), selected from the 1122 hrHPV + women of this trial.
Neurosci Lett
January 2024
Department of Psychology, School of Philosophy, Science and Literature of Ribeirão Preto of the University of São Paulo, Brazil. Electronic address:
Depending on its duration and severity, stress may contribute to neuropsychiatric diseases such as depression and anxiety. Studies have shown that stress impacts the hypothalamic-pituitary-adrenal (HPA) axis, but its downstream molecular, behavioral, and nociceptive effects remain unclear. We hypothesized that a 2-hour single exposure to acute restraint stress (ARS) activates the HPA axis and changes DNA methylation, a molecular mechanism involved in the machinery of stress regulation.
View Article and Find Full Text PDFChem Res Toxicol
December 2023
Epidemiology and Public Health Group, Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, U.K.
Human exposure to DNA alkylating agents is poorly characterized, partly because only a limited range of specific alkyl DNA adducts have been quantified. The human DNA repair protein, -methylguanine -methyltransferase (MGMT), irreversibly transfers the alkyl group from DNA -alkylguanines (-alkGs) to an acceptor cysteine, allowing the simultaneous detection of multiple -alkG modifications in DNA by mass spectrometric analysis of the MGMT active site peptide (ASP). Recombinant MGMT was incubated with oligodeoxyribonucleotides (ODNs) containing different -alkGs, Temozolomide-methylated calf thymus DNA (Me-CT-DNA), or human colorectal DNA of known -MethylG (-MeG) levels.
View Article and Find Full Text PDFComp Biochem Physiol B Biochem Mol Biol
January 2024
School of Earth, Environmental, and Marine Sciences, University of Texas Rio Grande Valley, Brownsville, Texas, USA.
Global warming is one of the greatest threats to living organisms. Among them, marine invertebrates are severely impacted on reproductive fitness by rising seawater surface temperatures due to climate change (e.g.
View Article and Find Full Text PDFFront Pharmacol
December 2022
School of Pharmacy, University of Waterloo, Waterloo, ON, Canada.
CD26/dipeptidyl peptidase IV (DPP4) is a cell-surface glycoprotein present on most epithelial cells that modulates the local response to external signals. We have previously shown that the dietary flavone apigenin (4',5,7-trihydroxyflavone) upregulates cell-surface CD26/DPP4 on human colorectal carcinoma (CRC) cells and regulates its activities. We observed a unique synergistic interaction with the CRC chemotherapeutic agent irinotecan, which through its metabolite SN38 elevates CD26 at doses that are sub-cytotoxic.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!