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A reconfigurable multi-mode multi-band transceiver for low power short-range wireless communication applications is presented. Its low intermediate frequency (IF) receiver with 3 MHz IF carrier frequency and the direct-conversion transmitter support reconfigurable signal bandwidths from 250 kHz to 2 MHz and support a highest data rate of 3 Mbps for MSK modulation. An integrated multi-band PLL frequency synthesizer is utilized to provide the quadrature LO signals from about 300 MHz to 1 GHz for the transceiver multi-band application. The transceiver has been implemented in a 0.18 μm CMOS process. The measurement results at the maximum gain mode show that the receiver achieves a noise figure (NF) of 4.9/5.5 dB and an input 3rd order intermodulation point (IIP3) of −19.6/−18.2 dBm in 400/900 MHz band. The transmitter working in 400/900 MHz band can deliver 10.2/7.3 dBm power to a 50 Ω load. The transceiver consumes 32.9/35.6 mW in receive mode and 47.4/50.1 mW in transmit mode in 400/900 MHz band, respectively.

A highly-transistorised bandpass filter (BPF) using a source-follower-based (SFB) resonator is proposed. It benefits from the advantageous properties of the source follower (e.g. no parasitic pole, linear V GS I/O relationship, high-input and low-output impedances), while combining it with a compact and low-power grounded differential active inductor to synthesise the complex poles. Fabricated in 90 nm CMOS, a fourth-order 75 MHz-IF BPF prototype merging two such SFB resonators measures a 10 MHz bandwidth at 2 mW of power. The die size is merely 0.07 mm 2 .

A wireless switch designated for battery-supplied implantable medical devices is designed and verified based on a passive RF receiver. The switch employs wireless energy recovery and wireless identification, and consumes zero standby power. Unlike the commonly used dry reed switch, the proposed switch features high tolerance to noise and disturbance, as well as compatibility with integrated circuits. The proposed wireless switch circuit has been implemented using 0.18 µm CMOS technology, and verified in a wireless capsule endoscope prototype system.

This study aimed to investigate the ability of chelerythrine chloride (CHE), the main active ingredient of Macleaya cordata, to induce apoptosis in human gastric cancer BGC-823 cells. The results demonstrate that CHE inhibits cell proliferation in a time- and dose-dependent manner with accompanying S phase arrest. It also induces apoptosis by a mechanism involving a reduction in the mitochondrial membrane potential, the release of cytochrome c, activation of caspase 3 and cleavage of poly-ADP-ribose polymerase. In addition, CHE-induced apoptosis is accompanied by down-regulation of Bcl-xl and Bcl-2 proteins with no change in the levels of Bax proteins. Taken together, the results support the development of CHE as a potentially useful anticancer drug for the treatment of gastric cancer.