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We designed and synthesized amphiphilic glycopeptides with glucose or galactose at the C-terminals. We observed the protein-induced structural changes of the amphiphilic glycopeptide assembly in the lipid bilayer membrane using transmission electron microscopy (TEM) and Fourier transform infrared reflection-absorption spectra (FTIR-RAS) measurements. The glycopeptides re-arranged to form a bundle that acted as an ion channel due to the interaction among the target protein and the terminal sugar groups of the glycopeptides. The bundle in the lipid bilayer membrane was fixed on a gold-deposited quartz crystal microbalance (QCM) electrode by the membrane fusion method. The protein-induced re-arrangement of the terminal sugar groups formed a binding site that acted as a receptor, and the re-binding of the target protein to the binding site induced the closing of the channel. We monitored the detection of target proteins by the changes of the electrochemical properties of the membrane. The response current of the membrane induced by the target protein recognition was expressed by an equivalent circuit consisting of resistors and capacitors when a triangular voltage was applied. We used peanut lectin (PNA) and concanavalin A (ConA) as target proteins. The sensing membrane induced by PNA shows the specific response to PNA, and the ConA-induced membrane responded selectively to ConA. Furthermore, PNA-induced sensing membranes showed relatively low recognition ability for lectin from Ricinus Agglutinin (RCA120) and mushroom lectin (ABA), which have galactose binding sites. The protein-induced self-organization formed the spatial arrangement of the sugar chains specific to the binding site of the target protein. These findings demonstrate the possibility of fabricating a sensing device with multi-recognition ability that can recognize proteins even if the structure is unknown, by the protein-induced self-organization process.

We demonstrate an ultra-low standby power embedded SRAM with cost effective test screening circuits on 110-nm SoC/MCU. A source bias design technique has been applied to reduce SRAM standby power in the resume standby mode where the stored data is retained. Meanwhile the testing time is increased due to the long pause time to screening the retention failures, because the source bias level will be shifted slightly by small SRAM leakage current. Therefore, a 2-stage test screening method for resume standby mode is newly proposed. It is applied for only low-temperature test loop to minimize the total testing time without any test coverage loss. Test chips including 130kbit SRAMs on 110-nm show full reading and writing operations and 0.28 pW/cell resume standby power at 1.5 V typical supply voltage and 25°C. The testing time is reduced to 1/50 by proposed 2-stage screening testing circuits with only 0.03% area overhead.

An effective standby power reduction of buffer/backup SRAM in MCU is proposed for power module IC (PMIC) less edge system in IoT applications. The proposed SRAM macro is implemented using 3.3 V thick-gate-oxide IO MOSs for effectively reducing the leakage power with source bias control techniques. Four multiples interleave wordline circuitry is also introduced to reduce read and write operating power. A test chip with 64-kbit SRAM macro is designed and fabricated using 40-nm technology. The measured data show that the leakage power is 330 nW at 65°C (47 nW at 25°C), which is 1/140 of other works. The read/write power is reduced by 60% by interleave wordline circuitry.

A method for selecting antibodies against a membrane protein is important for attaining a variety of antibody-based diagnostics and therapies. In this study, we propose a novel system to select specific antibodies against a membrane protein based on mammalian cell proliferation as a readout. The system employs a chimeric membrane protein in which a target membrane protein of interest is fused to the intracellular signaling domain of a cytokine receptor. The chimeric membrane protein transduces a cell proliferation signal through dimerization when co-expressed with a specific single-chain Fv fused with a mutant of FK-binding protein 12 (scFv-Fk) that can be conditionally dimerized by a synthetic ligand AP20187. To demonstrate this system, ErbB2 and gp130 were chosen as the target membrane protein and cytokine receptor, respectively. Consequently, co-expression of the ErbB2/gp130 chimera and ErbB2-specific scFv-Fk rendered the cells proliferative in response to AP20187. The system also allowed selection of high-affinity binders from a mixture composed of dominant low-affinity binders. This system may be extended to affinity maturation of scFvs by modulating AP20187 concentration in the selection process.

Background Surfing is an increasingly popular activity and surfing-related injuries have increased accordingly. However, to the best of our knowledge, there are no reports of penetrating upper airway injuries in surfers. We present a “cannot ventilate, cannot intubate” situation following penetrating neck injury by a surfboard fin. Case presentation A previously healthy 29-year-old Japanese man was swept off his board by a large wave and his left mandible, tongue root, and right epipharynx were penetrated by the surfboard fin. He presented with severe hypovolemic shock because of copious bleeding from his mouth. Direct laryngoscopy failed, as did manual ventilation, because of the exacerbated upper airway bleeding and distorted upper airway anatomy. Open cricothyrotomy was immediately performed, followed by surgical exploration, which revealed extensive ablation of his tongue root and laceration of his lingual artery. After definitive hemostasis and intensive care, he returned home with no sequelae. Conclusions The long, semi-sharp surfboard fin created both extensive crushing upper airway lesions and a sharp vascular injury, resulting in a difficult airway. This case illustrates that surfing injuries can prompt a life-threatening airway emergency and serves as a caution for both surfers and health care professionals.

A method for selecting antibodies against a membrane protein is important for attaining a variety of antibody-based diagnostics and therapies. In this study, we propose a novel system to select specific antibodies against a membrane protein based on mammalian cell proliferation as a readout. The system employs a chimeric membrane protein in which a target membrane protein of interest is fused to the intracellular signaling domain of a cytokine receptor. The chimeric membrane protein transduces a cell proliferation signal through dimerization when co-expressed with a specific single-chain Fv fused with a mutant of FK-binding protein 12 (scFv-Fk) that can be conditionally dimerized by a synthetic ligand AP20187. To demonstrate this system, ErbB2 and gp130 were chosen as the target membrane protein and cytokine receptor, respectively. Consequently, co-expression of the ErbB2/gp130 chimera and ErbB2-specific scFv-Fk rendered the cells proliferative in response to AP20187. The system also allowed selection of high-affinity binders from a mixture composed of dominant low-affinity binders. This system may be extended to affinity maturation of scFvs by modulating AP20187 concentration in the selection process.