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WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Some non-anti-arrhythmic drugs delay cardiac repolarization, which can be measured as an increase in the QT interval. Delays in cardiac repolarization create an electrophysiological environment that favours the development of cardiac arrhythmias, which may lead to torsade de pointes, which can be fatal. As part of the clinical development of eltrombopag, a thorough QTc study was conducted to evaluate the effects of eltrombopag on cardiac repolarization at both therapeutic and supratherapeutic doses and to characterize the relationship between plasma eltrombopag concentrations and change in QTc. WHAT THIS STUDY ADDS This study found no clinically significant QT prolongation for eltrombopag when administered as 50 mg or 150 mg every day for 5 days. There were no safety or tolerability signals of clinical concern. A small incidence of ventricular premature beats was observed, but this was consistent with previously reported incidences in healthy volunteers without apparent heart disease. AIM To evaluate the effect of eltrombopag on cardiac repolarization and to characterize the relationship between plasma eltrombopag concentrations and change in QTc. METHODS This was a double-blind, placebo- and active-controlled, randomized, balanced four-period, crossover study in healthy men and women. Subjects were randomized to receive eltrombopag 50 mg and 150 mg, moxifloxacin 400 mg (positive control) and placebo in one of four sequences. RESULTS Eighty-seven subjects entered the study and 48 completed. There was no prolongation of QTc (Fridericia) following eltrombopag treatment, as the upper limit of the 90% confidence interval (CI) for the time-matched change from baseline in QTcF between drug and placebo (ddQTcF) did not exceed 10 ms for eltrombopag at either dose. Maximum observed mean treatment difference was 2.29 ms (90% CI 0.34, 4.24) for eltrombopag 150 mg at 1 h post-dose and 11.64 ms (90% CI 9.64, 13.64) for moxifloxacin 400 mg at 4 h. Eltrombopag Cmax and AUC(0,24 h) increased in a dose proportional manner between 50 mg and 150 mg after 5 days' dosing. Proportions of subjects with adverse events were similar across treatments (52–66% of subjects). Most withdrawals (26/39 subjects) were due to elevated platelets. Three subjects were withdrawn for ventricular premature beats (one following each active treatment) reported as related to the study drug. CONCLUSIONS No clinically significant QTc prolongation was observed for eltrombopag at therapeutic and supratherapeutic doses. [ABSTRACT FROM AUTHOR]

nalyse de séries chronologiques censurées au moyen de modèles autorégressifs à moyenne mobile Les auteurs s'intéressent à des séries chronologiques dont certaines observations sont censurées lorsqu'elles dépassent un certain seuil. Règle générale, les praticiens ne tiennent pas compte des cas de censure, ce qui induit souvent un biais d'estimation. Les auteurs présentent une façon élégante de traiter des données autocorrélées censurées au moyen d'une classe de modèles autorégressifs à moyenne mobile (ARMA). En particulier, ils proposent une méthode d'imputation bien adaptée à l'ajustement de modèles ARMA en présence de censure. Ils démontrent la bonne performance de leur technique aux plans du biais, de l'efficacité et de la perte d'information. Ils montrent aussi comment elle peut être adaptée au contexte spécifique de données météorologiques temporelles sur la hauteur du plafond nuageux, dont l'évaluation est limitée par la capacité de l'instrument de mesure. [ABSTRACT FROM AUTHOR]

Background: Since severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) was first reported in Wuhan, China, in December 2019, it has spread rapidly, and many coronavirus disease (COVID‐19) cases have occurred in Gwangju, South Korea. Viral mutations following the COVID‐19 epidemic have increased interest in the characteristics of epidemics in this region, and pathogen genetic analysis is required for infection control and prevention. Methods: In this study, SARS‐CoV‐2 whole‐genome analysis was performed on samples from patients with COVID‐19 in Gwangju from 2020 to 2022 to identify the trends in COVID‐19 prevalence and to analyze the phylogenetic relationships of dominant variants. B.41 and B.1.497 prevailed in 2020, the early stage of the COVID‐19 outbreak; then, B.1.619.1 mainly occurred until June 2021. B.1.617.2, classified as sublineages AY.69 and AY.122, occurred continuously from July to December 2021. Since strict measures to strengthen national quarantine management had been implemented in South Korea until this time, the analysis of mutations was also able to infer the epidemiological relationship between infection transmission routes. Since the first identification of the Omicron variant in late December 2021, the spread of infection has been very rapid, and weekly whole‐genome analysis of specimens has enabled us to monitor new Omicron sublineages occurring in Gwangju. Conclusions: Our study suggests that conducting regional surveillance in addition to nation‐level genomic surveillance will enable more rapid and detailed variant surveillance, which will be helpful in the overall prevention and management of infectious diseases. [ABSTRACT FROM AUTHOR]

The symmetry reduction of molecular shape of cationic chromophores as a design strategy to develop organic terahertz (THz) generators is used. Electron donating group (EDG) with an asymmetric shape is introduced into two types of cationic styryl‐quinolinium chromophores, leading to the development of several novel non‐centrosymmetric crystals with high macroscopic optical nonlinearity. In contrast, when an EDG with a symmetric shape is introduced, centrosymmetric crystal structure is obtained in all investigated crystals. For THz wave generation, crystals based on asymmetrically shaped EDG exhibit several optimal crystal characteristics, including a plate‐shape morphology, a large size, and an in‐plane polar axis. Furthermore, over the entire range of molecular phonon vibrations, 0.5–4 THz, the steric hindrance group in the asymmetrically shaped EDG has a strong influence on the suppression of THz phonon vibrations, leading to a low THz absorption coefficient. The crystals based on asymmetrically shaped EDG generate an ≈40 times stronger THz electric field than the inorganic ZnTe crystal and very broad THz spectra, extending up to 16 THz. Thus, the symmetry reduction of the molecular shape of cationic chromophores through the introduction of an asymmetrically shaped EDG is an effective design approach for the development of novel organic THz crystals. [ABSTRACT FROM AUTHOR]

Eltrombopag, an oral, small-molecule, nonpeptide thrombopoietin receptor agonist for the treatment of thrombocytopenia, is highly protein bound and primarily eliminated via metabolism in the liver and gastrointestinal tract. Single-dose eltrombopag pharmacokinetics were evaluated in participants with hepatic or renal impairment given possible changes in systemic exposure due to reduced plasma protein binding or reduced metabolism. All participants received a single 50-mg dose of eltrombopag. The adverse event profile was similar across groups, with headache, nausea, and back pain most frequently reported. Compared with healthy participants, participants with mild, moderate, or severe hepatic impairment had mean increases in AUC0-∞ of 41%, 93%, and 80%, and participants with mild, moderate, or severe renal impairment had mean decreases in AUC0-∞ of 32%, 36%, and 60%. There was high pharmacokinetic variability and significant overlap in exposures between participants with hepatic or renal impairment and healthy participants. Results suggest that patients with renal impairment may initiate eltrombopag with the standard 50-mg once-daily starting regimen, whereas patients with moderate or severe hepatic impairment should consider a lower 25-mg once-daily regimen. Patients with hepatic or renal impairment should be closely monitored for platelet response and safety, and eltrombopag doses should be adjusted accordingly. [ABSTRACT FROM PUBLISHER]