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Halvorsen posted an update 7 months, 1 week ago
In comparing the oxidative and reductive rates of metabolism under anaerobic conditions, we have come to the conclusion that despite having similar rates of reduction (4-fold difference), the oxidation rate in mAO is more than 50-fold slower than hAO. This finding implies that the presence of nonlinearity in AO kinetics is dependent upon the degree of imbalance between the rates of oxidation and reduction in this enzyme. Olaparib PARP inhibitor SIGNIFICANCE STATEMENT Although they have as much as 95.1% sequence identity, human and cynomolgus monkey aldehyde oxidase are kinetically distinct. Therefore, monkeys may not be good estimators of drug clearance in humans.NAD+ is a critical molecule that is involved in multiple cellular functions. CD38 is a multifunctional enzyme with NAD+ nucleosidase activity. Our previous work revealed the CD38-dependent interactions of isoniazid (INH), an antituberculosis drug, with NAD+ to form INH-NAD adduct. In the current work, our metabolomic analysis discovered a novel NAD+ adduct with acetylisoniazid (AcINH), a primary INH metabolite mediated by N-acetyltransferase (NAT), and we named it AcINH-NAD. Using Nat1/2(-/-) and Cd38(-/-) mice, we determined that AcINH-NAD formation is dependent on both NAT and CD38. Because NAT is expressed in hepatocytes (HP), whereas CD38 is expressed in Kupffer cells (KC) and hepatic stellate cells (HSC), we explored cell type-specific roles of CD38 in the formation of AcINH-NAD as well as INH-NAD. We found that both INH-NAD and AcINH-NAD were produced in the incubation of INH or AcINH with KC and HSC but not in HP. These data suggest that hepatic nonparenchymal cells, such as KC and HSC, are the major cell types responsible for the CD38-dependent interactions of INH with NAD+ in the liver. SIGNIFICANCE STATEMENT The current study identified AcINH-NAD as a novel metabolite of INH in the liver. Our work also revealed the essential roles of nonparenchymal cells, including Kupffer cells and hepatic stellate cells, in the CD38-dependent interactions of NAD+ with INH, leading to the formation of both INH-NAD and AcINH-NAD in the liver. These data can be used to guide the future studies on the mechanisms of INH and NAD+ interactions and their contributions to INH-induced liver injury.Anti-Ly6E-seco-cyclopropabenzindol-4-one dimer antibody-drug conjugate (ADC) has been reported to form an adduct with α1-microglobulin (A1M) in animal plasma, but with unknown impact on ADC PK and tissue distribution. In this study, we compared the PK and tissue distribution of anti-Ly6E ADC with unconjugated anti-Ly6E mAb in rodents and monkeys. For PK studies, animals received an intravenous administration of anti-Ly6E ADC or unconjugated anti-Ly6E mAb. Plasma samples were analyzed for total antibody (Tab) levels and A1M adduct formation. PK parameters were generated from dose-normalized plasma concentrations. Tissue distribution was determined in tumor-bearing mice after a single intravenous dosing of radiolabeled ADC or mAb. Tissue radioactivity levels were analyzed using a gamma counter. The impact of A1M adduct formation on target cell binding was assessed in an in vitro cell binding assay. The results show that ADC Tab clearance was slower than that of mAb in mice and rats but faster than mAb in monkeyanistic understanding of ADC biotransformation, which could provide insight into ADC molecule design, optimization, and selection.Imeglimin is a novel oral antidiabetic drug for treatment of type 2 diabetes that targets mitochondrial bioenergetics. Its pharmacokinetics absorption characteristics, metabolism, distribution, and elimination were assessed through several in vitro and in vivo experiments in both animals and humans. Its potential to induce drug-drug interactions was also extensively assessed. Imeglimin is a small cationic compound with an intermediate intestinal permeability. Its absorption mechanism involves an active transport process in addition to passive paracellular absorption. Absorption was good (50%-80%) in vivo across several species but decreased with increasing dose, probably because of saturation of active transport. After absorption, imeglimin was rapidly and largely distributed to internal organs. Plasma protein binding was low, which can explain the rapid distribution to organs observed in all species. In animals and humans, imeglimin was largely excreted unchanged in urine, indicating a low extent of metaboli2-K and also a substrate and an inhibitor of OCT1, OCT2, and MATE1 transporters; however, there are no clinically significant interactions when imeglimin is coadministered with either a substrate or an inhibitor of these transporters.
Guidelines for drug information (DI) provided by hospital pharmacists call for quality assurance procedures; however, no method of evaluation is internationally agreed on. The procedure should be feasible, reproducible and representative for real-life quality. We tested a new approach using a fictitious enquiry under simulated real-life conditions for quality assessment of DI by German hospital pharmacists.
A fictitious enquiry was submitted under simulated real-life conditions (study part I; test week announced, but not exact day; response time given). An expert panel determined content-related (three essential, and up to seven additional items of useful information) and structural requirements for answers and performed blinded evaluations. To compare quality of routine DI answers (study part II), five recently answered routine enquiries could retrospectively be evaluated for plausibility (binary scale 0/1) and structural requirements.
Of 62 hospital pharmacies opting to participate, 45 (71%) entered slity measurement of DI of hospital pharmacists and identifies areas for improvement.
Dalbavancin is approved for the treatment of complicated skin and soft tissue infections. However, there is growing evidence that other gram-positive infections could be treated with this antibiotic. A study was undertaken in a tertiary hospital in Spain to evaluate the effectiveness and safety of dalbavancin in off-label indications and the potential healthcare cost savings.
A retrospective observational study including all patients treated with dalbavancin in our hospital from October 2016 to August 2019 was carried out. Demographic, clinical and safety variables were collected. Effectiveness was assessed using the clinical and microbiological resolution of the infection and the absence of hospital admissions due to the same infection in the following 3 months.
A total of 102 patients were included (69.9% men, n=71; median age 72.5 years (range 56.0-84.0)). Treatment was off label in 71 cases (69.6%). The most frequent off-label indications were catheter-related bacteraemia (15.7%, n=16) and endocarditis (13.