Age-related difference in oral adaptation to masticatory perturbation.

OBJECTIVES: Mastication can be influenced by intraoral perturbation (e.g., hard food). We developed the masticatory perturbation task (MPT) to assess the perturbation effect during mastication and quantify the degree of adaptation to masticatory perturbation in younger and older adults. DESIGN: Thirty-eight younger and 38 older participants completed the MPT, which consisted of three trials assessing masticatory performance (MP) without perturbation (i.e., the baseline condition) and three trials assessing MP with perturbation (i.e., the perturbation condition). Perturbation was implemented by concurrently chewing test food on the preferred side and a drinking straw on the nonpreferred side. We estimated the perturbation effect as the ΔMP between the baseline and perturbation conditions and the adaptation effect as the ΔMP between the third and the first trials for both age groups. RESULTS: We found a significant perturbation effect, i.e., a lower MP in the perturbation condition than in the baseline condition, and an adaptation effect, i.e., a higher MP in the third trial than the first trial, in both groups. Moreover, the older group showed a lower degree of adaptation than the younger group. CONCLUSION: The masticatory perturbation task revealed the perturbation effect during mastication and the adaptation to masticatory perturbation. The results revealed an association between age and masticatory adaptation.

Detection of C-reactive protein on an integrated microfluidic system by utilizing field-effect transistors and aptamers.

Cardiovascular diseases (CVDs) cause more than 17 × 106 deaths worldwide on a yearly basis. Early diagnosis of CVDs is therefore of great need. The C-reactive protein (CRP) is an important biomarker for analyzing the risks of CVDs. In this work, CRP-specific aptamers with high sensitivity and specificity and field-effect-transistor (FET) devices were used to recognize and detect CRP by using an integrated microfluidic system automatically while consuming less volumes of reagents and samples (about 5 µm). In order to package the FET device into the microfluidic chip, a new method to prevent liquid leakage was proposed. Sensitive detection of CRP has been demonstrated on the developed microfluidic system. It is the first time that aptamer-FET assays could be realized on an integrated microfluidic system. Experimental results showed that the aptamer-FET assay was capable of detecting CRP with concentrations ranging from 0.625 mg/l to 10.000 mg/l, which may be promising for early diagnosis of CVDs.