Na+/H+ Exchanger 1, a Potential Therapeutic Drug Target for Cardiac Hypertrophy and Heart Failure.

Cardiac hypertrophy is defined as increased heart mass in response to increased hemodynamic requirements. Long-term cardiac hypertrophy, if not counteracted, will ultimately lead to heart failure. The incidence of heart failure is related to myocardial infarction, which could be salvaged by reperfusion and ultimately invites unfavorable myocardial ischemia-reperfusion injury. The Na+/H+ exchangers (NHEs) are membrane transporters that exchange one intracellular proton for one extracellular Na+. The first discovered NHE isoform, NHE1, is expressed almost ubiquitously in all tissues, especially in the myocardium. During myocardial ischemia-reperfusion, NHE1 catalyzes increased uptake of intracellular Na+, which in turn leads to Ca2+ overload and subsequently myocardial injury. Numerous preclinical research has shown that NHE1 is involved in cardiac hypertrophy and heart failure, but the exact molecular mechanisms remain elusive. The objective of this review is to demonstrate the potential role of NHE1 in cardiac hypertrophy and heart failure and investigate the underlying mechanisms.

Optimized response of the AlGaN/GaN heterostructure with asymmetric gratings at oblique incidence in the terahertz regime.

The performance of terahertz (THz) detectors based on two-dimensional electron gas (2DEG) with the aid of a subwavelength gratings coupler depends critically on the amplitude difference of an electric field with positive and negative scattering orders. An efficient method was proposed to enhance the current response of the AlGaN/GaN material in the frequency range from 0 to 5 THz under oblique incidence of THz radiation with asymmetric gratings, where the optimal incidence angle exists. The case of symmetric gratings was also studied for comparison. The results will be useful for the theoretical and experimental optimization of grating-assisted THz detectors without electrical bias.

Yolk-shell structured Au nanorods@mesoporous silica for gas bubble driven drug release upon near-infrared light irradiation.

Drug release systems co-encapusulated with ammonium bicarbonate (ABC) could facilitate drug release upon acidic or thermal stimulations to improve therapeutic effect. However, it is not easy to control drug release rate, owing to relative stable temperature and acidic condition in living body. Besides, the additional loaded ABC reduces drug loading capacity. Herein, a near-infrared light triggered rapid drug release system with high loading capacity was developed by loading ABC and doxorubicin into yolk-shell structured Au nanorods@mesoporous silica. Gas bubbles were generated from the thermolysis of ABC utilizing photothermal effect of Au nanorods to extrude drug molecules. The mesoporous silica shell was finally destroyed along with growing bubbles, resulting in burst drug release. The photothermal therapeutic effect of Au nanorods also contributed in tumor treatment. The excellent therapeutic effect was demonstrated in cancer cells and tumor-bearing mice, which provides a new reference to achieve controllable rapid drug release in cancer medicine.