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Aims: Few studies have investigated linezolid (LZD)-associated cardiotoxicity. This study explored the potential association between LZD and QT interval prolongation. Methods: Adverse event reports of QT interval prolongation associated with LZD from the Food and Drug Administration Adverse Event Reporting System from January 2013 to December 2021 were analysed and the reporting odds ratio (ROR) with 95% confidence intervals were calculated. Results: A total of 6738 adverse event reports of LZD as the primary and secondary suspected drug were obtained from the database, including 192 reports with electrocardiogram QT prolonged (QTp), and the ROR value was 26.1 (95% CI = 22.6–30.2). There were 8 reports of long QT syndrome, ROR 14.2 (95% CI = 7.1–28.5); 5 reports of torsade de pointes, ROR 3.2 (95% CI = 1.3–7.6); and 5 reports of ventricular tachycardia, ROR 1.9 (95% CI = 0.8–4.5). Subgroup analysis revealed that patients with tuberculosis treated with LZD had a higher reporting rate among all QTp reports, exhibiting an odds ratio of 330.0 (95% CI = 223.1–488.1). The odds ratios of QTp associated with LZD treatments in patients with and without tuberculosis were 4.2 (95% CI = 3.4–5.3) and 1.2 (95% CI = 0.8–1.6), respectively. Conclusion: The study showed an association between LZD and QT interval prolongation. In the report on patients with tuberculosis, the incidence of QTp was higher when treated with LZD. [ABSTRACT FROM AUTHOR]

Coxsackie virus B5 (CVB5), a main serotype in human Enterovirus B (EVB), can cause severe viral encephalitis and aseptic meningitis among infants and children. Currently, there is no approved vaccine or antiviral therapy available against CVB5 infection. Here, we determined the atomic structures of CVB5 in three forms: mature full (F) particle (2.73 Å), intermediate altered (A) particle (2.81 Å), and procapsid empty (E) particle (2.95 Å). Structural analysis of F particle of CVB5 unveiled similar structures of "canyon," "puff," and "knob" as those other EV-Bs. We observed structural rearrangements that are alike during the transition from F to A particle, indicative of similar antigenicity, cell entry, and uncoating mechanisms shared by all EV-Bs. Further comparison of structures and sequences among all structure-known EV-Bs revealed that while the residues targeted by neutralizing MAbs are diversified and drive the evolution of EV-Bs, the relative conserved residues recognized by uncoating receptors could serve as the basis for the development of antiviral vaccines and therapeutics. [ABSTRACT FROM AUTHOR]

Objectives The objective of this study was to investigate the possible interaction of shikonin and β,β-dimethylacrylshikonin (DSK) with tramadol. Methods Human liver microsome (HLM) and rat liver microsome (RLM) incubation experiments were carried out to assess the half-maximal inhibitory concentration (IC50) and inhibitory mechanism of shikonin and DSK on tramadol metabolism in vitro. And pharmacokinetics experiments containing low and high doses of shikonin and DSK were performed to confirm the inhibitory effects on tramadol metabolism in vivo. Key findings The IC50 of shikonin on tramadol metabolism was 5.66 ± 1.2 μmol/l in HLM and 3.35 ± 1.1 μmol/l in RLM, while that of DSK on tramadol metabolism was 14.33 ± 1.1 μmol/l in HLM and 8.24 ± 1.26 μmol/l in RLM. Moreover, shikonin and DSK showed non-competitive inhibition of the cytochrome P450 enzyme in both HLM and RLM. Oral administration of 10 and 30 mg/kg shikonin inhibited tramadol metabolism in a dose-dependent manner. Furthermore, a dose of 30 mg/kg DSK inhibited the metabolism of tramadol in rats, while the lower dose of 10 mg/kg showed no inhibitory effect. Conclusions The results of this study suggest that shikonin and DSK can inhibit tramadol metabolism both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

The recurving cluster of tropica cyclones (TCs) landing at China in spring has the characteristics of high frequency, strong intensity, severe influence and long lifespan, a better understanding of tropical cyclone tracks and their underlying mechanisms and more accurate prediction are thus of great value for the prevention and mitigation of TC-related disasters. Based on the best track dataset of typhoon during 1951-2018 from Shanghai Typhoon Institute (STI) of Chinese Meteorological Administration, the tracks of tropical cyclones landfalling over the Chinese coast during 1951-2018 are grouped into three clusters through finite mixture model. The ENSO index, PDO index and the 74 circulation indices of the National Climate Center are analyzed by the classification and regression tree (CART) algorithm for the first TC cluster (the northward-moving cluster). The prediction model based on the results of CART for spring track lifespan is built by a random sampling of the data during the 50 years (about 75% ) as a model of the training set, and the training accuracy is 82. 46%. The 17-year ( about 25% ) remaining data are used for testing, with a prediction accuracy of 75%. This study suggests that the finite mixture model algorithm produces a better classification of the northward-going-cluster tracks of TC landfalling over China. In addition, the CART algorithm, which is used for the classification of track lifespan prediction model, not only shows high accuracy, but also the results are easily explained and understood. It provides a novel idea for forecasting the lifespan of tropical cyclones landing at China. [ABSTRACT FROM AUTHOR]

This work investigates a state estimation problem for linear time-invariant systems based on polarized measurement information from event sensors. To enable estimator design, a new notion of observability, namely,\epsilon-observability is defined with the precision parameter\epsilon which relates to the worst-case performance of inferring the initial state, based on which a criterion is developed to test the\epsilon-observability of discrete-time linear systems. Utilizing multisensor polarity data from event sensors and the implicit information hidden in event-triggering conditions at no-event instants, an iterative event-triggered state estimator is designed to evaluate a set containing all possible values of the state. The proposed estimator is built by outer approximation of intersecting ellipsoids that are predicted from previous state estimates and the ellipsoids inferred from received polarity information of event sensors as well as the event-triggering protocol; the estimated regions of the state derived from multisensor event measurements are fused together, the sizes of which are proved to be asymptotically bounded. Distributed implementation of the estimation algorithm utilizing a two-layer processor network of hierarchy architecture is discussed, and the temporal computational complexity of the algorithm implemented in centralized and distributed ways is analyzed. The efficiency of the proposed event-triggered state estimator is verified by numerical experiments. [ABSTRACT FROM AUTHOR]

In this work, a parameter tuning problem of two-degrees-of-freedom model predictive control of industrial paper-making processes is explored to achieve satisfactory time-domain robust closed-loop performance in terms of worst-case overshoots and worst-case settling times, under user-specified parametric uncertainties. An efficient visualization method is first developed to characterize the set of time-domain closed-loop responses in the presence of parametric model-plant mismatch. On the basis of the visualization technique and the unmodality/monotonicity properties of the performance indices with respect to the tuning parameters, the feasibility of the tuning problem can be analyzed, and a three-step iterative line-search based automatic tuning algorithm is proposed to determine the controller parameters that meet the time-domain performance requirements robustly for the given parametric uncertainty specifications. The effectiveness of the algorithm is illustrated by applying the results to a process from stock to conditioned weight in an industrial paper machine and by comparing the performance of the algorithm with that of brutal search. [ABSTRACT FROM AUTHOR]

The Hedgehog (Hh) signaling pathway plays evolutionarily conserved roles in controlling embryonic development and tissue homeostasis, and its dysregulation has been implicated in many human diseases including congenital disorder and cancer. The Hh pathway has a unique signal reception system that includes two membrane proteins, the receptor Patched (Ptc) and the transducer Smoothened (Smo). In the Hh signaling cascade, Smo plays a critical role in controlling transduction of Hh gradient signal from the outside into the inside of cells. Although the Smo downstream signal transduction has been intensively studied, the mechanism by which Smo on the plasma membrane is regulated has not been fully understood. As a specific membrane structure of metazoan cells, lipid rafts act as a platform to regulate signal transduction by forming a nanoscale cluster through protein-protein or protein-lipid interactions. However, it remains largely unknown whether lipid rafts are also involved in the regulation of Hh signal transduction. Here, we show that Smo extracellular domain (N terminus) and transmembrane domains form oligomers/higher order clusters in response to Hh signal. Furthermore, we identify that lipid rafts on the plasma membrane are essential for high level activity of Smo during the Hh signal transduction. Finally, our observation suggests that oligomerization/higher order clustering of Smo C-terminal cytoplasmic tail (C-tail) is essential for the transduction of high level Hh signal. Collectively, our data support that in response to Hh gradient signals, Smo transduces high level Hh signal by forming oligomers/higher order clusters in the lipid rafts of cell plasma membrane. [ABSTRACT FROM AUTHOR]

A letter to the editor about the prevalence of extensively drug-resistant tuberculosis in Central China from 2007 to 2009 is presented.

In winter, greenhouses located in mid to high latitudes are required a function of dehumidification and warming due to the low outdoor temperature. Focusing on small spires greenhouses, this study regulates the low temperature and high humidity environment inside the greenhouse and proposes a new-type of greenhouse heat and humidity regulation system by combining composite solid desiccant dehumidification with ground heat exchange system. The greenhouse internal environment is warmed and dehumidified at night by utilizing the adsorption effect of the compound dehumidifier and the sensible heat exchange between the heat exchange system in the ground and the greenhouse. Solar thermal energy is collected during the day using multi-curved tank collector (MTC) for thermal storage in the geothermal system and desiccant desorption. The rationality of pipeline layout is verified through CFD simulation, and the indoor temperature and humidity distribution during the system operation is explored. The experimental results show that the moisture adsorption capacity of the composite desiccant SG-CaCl 2 for 10h is 0.511 g/g. The optimal regeneration temperature is 80–100 °C. This system can reduce the nighttime relative humidity of the greenhouse in winter from 96.5 % to 83.6 %, and the average indoor air temperature after warming is 12.8 °C. The heat exchange efficiency of the underground heating exchange system is 0.38. During the desorption phase on daytime, the maximum outlet temperature of MTC is 103.8 °C, and the average heat collection efficiency is 0.42. The system can effectively regulate the air environment in the greenhouse to the appropriate zone for crop growth by combining solar thermal collector technology with recyclable solid dehumidification technology. • A novel heat and humidity control system of solar greenhouse with composite desiccants was proposed. • The performance of the system is analyzed in detail through experiments and simulations. • The moisture adsorption capacity of the composite desiccant SG-CaCl 2 for 10h is 0.511 g/g. • This system can reduce the nighttime relative humidity of the greenhouse in winter from 96.5 % to 83.6 %. [ABSTRACT FROM AUTHOR]

SmCo5 based magnets with smaller size and larger maximum energy product have been long desired in various fields such as renewable energy technology, electronic industry and aerospace science. However, conventional relatively rough synthetic strategies will lead to either diminished magnetic properties or irregular morphology, which hindered their wide applications. In this article, we present a facile chemical approach to prepare 200 nm single domain SmCo5@Co core/shell magnets with coercivity of 20.7 kOe and saturation magnetization of 82 emu/g. We found that the incorporation of GO sheets is responsible for the generation of the unique structure. The single domain SmCo5 core contributes to the large coercivity of the magnets and the exchange-coupled Co shell enhances the magnetization. This method can be further utilized in the synthesis other Sm-Co based exchange-coupled magnets. [ABSTRACT FROM AUTHOR]