Long QT syndrome (LQTS) is a heritable disease associated with ECG QT interval prolongation, ventricular tachycardia, and sudden cardiac death in young patients. Among genotyped individuals, mutations in genes encoding repolarizing K + channels (LQT1:KCNQ1; LQT2:KCNH2) are present in approximately 90% of affected individuals. Expression of pore mutants of the human genes KCNQ1 (KvLQT1-Y315S) and KCNH2 (HERG-G628S) in the rabbit heart produced transgenic rabbits with a long QT phenotype. Prolongations of QT intervals and action potential durations were due to the elimination of I Ks and I Kr currents in cardiomyocytes. LQT2 rabbits showed a high incidence of spontaneous sudden cardiac death (>50% at 1 year) due to polymorphic ventricular tachycardia. Optical mapping revealed increased spatial dispersion of repolarization underlying the arrhythmias. Both transgenes caused downregulation of the remaining complementary I Kr and I Ks without affecting the steady state levels of the native polypeptides. Thus, the elimination of 1 repolarizing current was associated with downregulation of the reciprocal repolarizing current rather than with the compensatory upregulation observed previously in LQTS mouse models. This suggests that mutant KvLQT1 and HERG interacted with the reciprocal wild-type α subunits of rabbit ERG and KvLQT1, respectively. These results have implications for understanding the nature and heterogeneity of cardiac arrhythmias and sudden cardiac death.

The aim is to develop a rapid and direct method for measuring the bulk viscosity of a liquid as a function of temperature. Brillouin scattering of a laser beam in fresh water and salt water at different temperatures has been studied. The results show that there exists a close temperature-dependent relationship among the Brillouin frequency shift, the Brillouin linewidth, and the bulk viscosity of water. Thus the bulk viscosity of water can be determined directly from Brillouin-scattering measurements. The method has a high signal-to-noise ratio and high accuracy.

It has been over 2 months since the start of the Coronavirus disease 2019 (COVID-19) outbreak.The epidemic stage of COVID-19 has brought great challenges to the diagnosis and management of colorectal cancer (CRC) patients. Symptoms, such as fever and cough caused by cancer, and the therapeutic process (including chemotherapy and surgery) should be differentiated from some COVID-19 related characteristics. Besides, clinical workers should not only consider the therapeutic strategy for cancer, but also emphasize COVID-19's prevention. Moreover, the detailed therapeutic regimens of CRC patients may be different from the usual. Also, treatment principles may various for CRC patients with or without severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, as well as patients with or without an emergency presentation. In this paper, we want to discuss the above-mentioned problems based on previous guidelines, the current working status and our experiences, to provide a reference for medical personnel.

An ultracompact plasmonic refractive index sensor based on Fano resonance is proposed. The sensor comprises a metal-insulator-metal waveguide with a stub and a side-coupled split-ring resonator. The effect of structural parameters on Fano resonance and the refractive index sensitivity of the system are analyzed in detail by investigating the transmission spectrum. Simulation results show that Fano resonance has different dependences on the parameters of the sensor structure. The reason is further discussed based on the field pattern. The peak wavelength and lineshape can be easily tuned by changing the key parameters. Furthermore, dual Fano resonance effects with different frequency intervals are obtained, which are mainly induced by the symmetry breaking of the structure. The proposed sensor yields sensitivity higher than 1.4×10 nm/RIU and a figure of merit of 1.2×10. The sensitivity and figure of merit can be further improved by optimizing the geometry parameters.

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