S 9788 is a novel triazinoaminopiperidine derivative which does not belong to any of the classes of compounds known to reverse multidrug resistance (MDR). S 9788 was far more potent than verapamil (VRP) in reversing resistance to adriamycin (ADR) in the ADR-selected murine leukaemia cell lines P388/ADR-1 and P388/ADR-10, and the human chronic myelogenous leukaemia K562/R. Fold reversion with S 9788 (5 microM) was, respectively, 3.5, 5.4 and 11.3 times greater than that with VRP (5 microM). S 9788 was also a more potent reversant of ADR resistance in the intrinsically resistant human colon adenocarcinoma COLO 320DM (2.3 fold), and of vincristine (VCR) resistance in the human MDR1 gene-transfected squamous lung carcinoma line S1/tMDR1 (5.6 fold). The activity of S 9788 depended on both the MDR cell line and the cytotoxic agent. S 9788 (50-100 mg/kg/d) administered IP once a day on days 1-4 resulted in a dose-dependent increase in the chemotherapeutic effect of VCR (0.25 mg/kg/d) in P388/VCR - bearing mice and ADR (4 mg/kg/d) in P388/ADR - bearing mice. Increases in antitumor activity were (% T/C) of +20-34% in the P388/ADR model and + 50-78% in the P388/VCR model with respect to cytotoxic agent treatment alone. S 9788 appeared to be devoid of toxicity at its effective doses. The mechanism of action of S 9788 is unknown but S 9788 (0.5-10 microM) induced a dose-dependent increase in ADR accumulation in KB-Al cells and compared to verapamil its effect was twice as active and approximately seven times more potent. We conclude that S 9788 is a novel agent capable of reversing MDR in vitro and in vivo, and whose pharmacological profile warrants its selection as a candidate drug for eventual assessment in the clinic.
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http://dx.doi.org/10.1007/BF00877238 | DOI Listing |
Hypertension
January 2025
Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (W.Z., D.H., M.A.M., Y.M.).
Background: Hypotensive episodes detected by 24-hour ambulatory blood pressure (BP) monitoring capture daily cumulative hypotensive stress and could be clinically relevant to cognitive impairment, but this relationship remains unclear.
Methods: We included participants from the Systolic Blood Pressure Intervention Trial (receiving intensive or standard BP treatment) who had 24-hour ambulatory BP monitoring measured near the 27-month visit and subsequent biannual cognitive assessments. We evaluated the associations of hypotensive episodes (defined as systolic BP drops of ≥20 mm Hg between 2 consecutive measurements that reached <100 mm Hg) and hypotensive duration (cumulative time of systolic BP <100 mm Hg) with subsequent cognitive function using adjusted linear mixed models.
Chemistry
January 2025
Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Campus E 8.1, 66123, Saarbrücken, Germany.
J Extracell Vesicles
December 2024
Unit for Plant Molecular Cell Biology, Institute for Biology I, RWTH Aachen University, Aachen, Germany.
J Clin Immunol
November 2024
Translational Immunology Research Group, Vall d'Hebron Research Institute (VHIR), Vall d'Hebron Barcelona Hospital Campus, Barcelona, Catalonia, Spain.
Bioeng Transl Med
September 2024
Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology Tianjin University Tianjin China.
Inflammatory bowel disease (IBD) is a chronic and unspecific inflammatory disorder of the gastrointestinal tract, and current treatment options often fail to maintain long-term remission. Studies have shown that propionate level is reduced in fecal samples from patients with IBD. Propionate can ameliorate IBD through intestinal epithelial cells and immune regulation, but its effects on the inflammatory microenvironment and macrophage differentiation have not been widely studied.
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