Cellular physiological approach for treatment of gastric cancer

Recent studies show that ion channels/transporters play important roles in fundamental cellular functions that would be involved in the cancer process. We review the evidence for their expression and functioning in human gastric cancer(GC), and evaluate the potential of cellular physiological approach in clinical management. Various types of ion channels, such as voltage-gated K+ channels, intracellular Cl- channels and transient receptor potential channels have been found to express in GC cells and tissues, and to control cell cycles. With regard to water channels, aquaporin 3 and 5 play an important role in the progression of GC. Regulators of intracellular pH, such as anion exchanger, sodiumhydrogen exchanger, vacuolar H+-ATPases and carbonic anhydrases are also involved in tumorigenesis of GC. Their pharmacological manipulation and gene silencing affect cellular behaviours, suggesting their potential as therapeutic targets for GC. Our studies indicate theintracellular Cl- concentration could act as a mediator of cellular signaling and control cell cycle progression in GC cells. Further, we demonstrate the cytocidal effects of hypotonic shock on GC cells, and indicate that the blockade of Cl- channels/transporters enhances these effects by inhibiting regulatory volume decrease. A deeper understanding of molecular mechanisms may lead to the discovery of these cellular physiological approaches as a novel therapeutic strategy for GC.

The Wireless Power Transmission on the Wristto-Forehead Path Based on the Body Channel

The body channel based wireless power transfer(BC-WPT)method utilizes the human body as the medium to transfer power for bioelectronics,which can achieve a lower transmission loss due to its higher conductivity.However,except for the channel length,different on-body loca-tions of the transmitter and receiver also influence the power supply performance.This paper fo-cuses on the wrist-to-forehead path to show the potential of BC-WPT for the brain bioelectronics such as the brain computer interface device.The channel characteristics from 10 MHz to 60 MHz are measured by a vector network analyzer(VNA)and a prototype BC-WPT system with differ-ent copper electrodes and the lowest power loss locates between-22 dB and-33 dB.Furthermore,the minimum path loss limit is simulated in Advanced Design System(ADS)software and the low-est optimum path loss can reach nearly-13 dB.Finally,a rectifier circuit is also built at the receiv-er side to harvest d.c.voltage.The results show that the open-circuit voltage(OCV)can reach 1.75 V with the transmitter of 50Ωoutput impedance supplying 5V_(pp)sine voltage at 60 MHz when adopt-ing 1 cm-diameter circular electrodes.

Recent progress in the structural study of ion channels as insecticide targets

Ion channels,many expressed in insect neural and muscular systems,have drawn huge attention as primary targets of insecticides.With the recent technical breakthroughs in structural biology,especially in cryo-electron microscopy(cryo-EM),many new high-resolution structures of ion channel targets,apo or in complex with insecticides,have been solved,shedding light on the molecular mechanism of action of the insecticides and resistance mutations.These structures also provide accurate templates for structure-based insecticide screening and rational design.This review summarizes the recent progress in the structural studies of 5 ion channel families:the ryanodine receptor(RyR),the nicotinic acetylcholine receptor(nAChR),the voltage-gated sodium channel(VGSC),the transient receptor potential(TRP)channel,and the ligand-gated chloride channel(LGCC).We address the selectivity of the channel-targeting insecticides by examining the conservation of key coordinating residues revealed by the structures.The possible resistance mechanisms are proposed based on the locations of the identified resistance mutations on the 3D structures of the target channels and their impacts on the binding of insecticides.Finally,we discuss how to develop“green”insecticides with a novel mode of action based on these high-resolution structures to overcome the resistance.

A 320 mV,6 kb subthreshold 10T SRAM employing voltage lowering techniques

This paper presents a 6 kb SRAM that uses a novel 10T cell to achieve a minimum operating voltage of 320 mV in a 130 nm CMOS process. A number of low power circuit techniques are included to enable the proposed SRAM to operate in the subthreshold region. The reverse short channel effect and the reverse narrow channel effect are utilized to improve the performance of the SRAM. A novel subthreshold pulse generation circuit produces an ideal pulse to make read operation stable. A floating write bit-line effectively reduces the standby leakage consumption. Finally, a short read bit-line makes the read operation fast and energy-saving. Measurements indicate that these techniques are effective, the SRAM can operate at 800 kHz and consume 1.94/zW at its lowest voltage （320 mV）.