Network model of chemical-sensing system inspired by mouse taste buds

Random pulse induced synchronization and resonance in uncoupled non-identical neuron models

Random pulses contribute to stochastic resonance in neuron models, whereas common random pulses cause stochastic-synchronized excitation in uncoupled neuron models. We studied concurrent phenomena contributing to phase synchronization and stochastic resonance following induction by a weak common random pulse in uncoupled non-identical Hodgkin-Huxley type neuron models. The common random pulse was selected from a gamma distribution and the degree of synchronization depended on the corresponding shape parameter. Specifically, a low shape parameter of the weak random pulse induced well-synchronized spiking in uncoupled neuron models, whereas a high shape parameter of the weak random pulse or a weak periodic pulse caused low degrees of synchronization. These were improved by concurrent inputs of periodic and random pulses with high shape parameters. Finally, the output pulse was synchronized with the periodic pulse, and the common random pulse revealed periodic responses in the present neuron models.

Development of Frequency Based Taste Receptors Using Bioinspired Glucose Nanobiosensor

A method to fabricate a bioinspired nanobiosensor using electronic-based artificial taste receptors for glucose diagnosis is presented. Fabricated bioinspired glucose nanobiosensor designated based on an artificial taste bud including an amperometric glucose biosensor and taste bud-inspired circuits. In fact, the design of the taste bud-inspired circuits was inspired by the signal-processing mechanism of taste nerves which involves two layers. The first, known as a type II cell, detects the glucose by glucose oxidase and transduces the current signal obtained for the pulse pattern is conducted to the second layer, called type III cell, to induce synchronisation of the neural spiking activity. The oscillation results of fabricated bioinspired glucose nanobiosensor confirmed an increase in the frequency of the output pulse as a function of the glucose concentration. At high glucose concentrations, the bioinspired glucose nanobiosensor showed a pulse train of alternating short and long interpulse intervals. A computational analysis performed to validate the hypothesis, which was successfully reproduced the alternating behaviour of bioinspired glucose our nanobiosensor by increasing the output frequency and alternation of pulse intervals according to the reduction in the resistivity of the biosensor.

Effect of sumatriptan on gastric emptying: A crossover study using the BreathID system

AIM: To determine the effect of oral sumatriptan on gastric emptying using a continuous ¹³C breath test (BreathID system).

METHODS: Ten healthy male volunteers participated in this randomized, 2-way crossover study. The subjects fasted overnight and were randomly assigned to receive a test meal (200 kcal/200 mL) 30 min after pre-medication with sumatriptan 50 mg (sumatriptan condition), or the test meal alone (control condition). Gastric emptying was monitored for 4 h after administration of the test meal by the ¹³C-acetic acid breath test performed continually using the BreathID system. Then, using Oridion Research Software (β version), the time taken for emptying of 50% of the labeled meal (T_1/2) similar to the scintigraphy lag time for 10% emptying of the labeled meal (T_lag), the gastric emptying coefficient (GEC), and the regression-estimated constants (β and κ) were calculated. The statistical significance of any differences in the parameters were analyzed using Wilcoxon’s signed-rank test.

RESULTS: In the sumatriptan condition, significant differences compared with the control condition were found in T_1/2 [median 131.84 min (range, 103.13-168.70) vs 120.27 min (89.61-138.25); P = 0.0016], T_lag [median 80.085 min (59.23-125.89) vs 61.11 min (39.86-87.05); P = 0.0125], and β [median 2.3374 (1.6407-3.8209) vs 2.0847 (1.4755-2.9269); P = 0.0284]. There were no significant differences in the GEC or κ between the 2 conditions.

CONCLUSION: This study showed that oral sumatriptan significantly delayed gastric emptying of a liquid meal.