Evaluation of electrical characteristics of biological tissue with electrical impedance spectroscopy.

The electrical characteristics of biological tissue is evaluated by establishing an electrical equivalent circuit with electrical impedance spectroscopy. The least squares method is used to realize electrical equivalent circuit fitting by using the developed portable electrical impedance spectroscopy system. The EIS system is used to obtain the impedance spectrum data of the measured biological tissue. In the experiment, the impedance spectrum data of eggs under different heating time were measured, and the established equivalent circuit model of eggs was fitted by nonlinear least squares fitting algorithm. Moreover, the electrical characteristics of the biological tissue are also revealed by numerical simulation with HANAI model. The experimental and simulation results show that the extracted equivalent electrical parameters can clearly characterize the variation of the internal change of components of biological tissues.

Development of a Wearable Electrical Impedance Tomographic Sensor for Gesture Recognition With Machine Learning.

A wearable electrical impedance tomographic (wEIT) sensor with 8 electrodes is developed to realize gesture recognition with machine learning algorithms. To optimize the wEIT sensor, gesture recognition rates are compared by using a series of electrodes with different materials and shapes. To improve the gesture recognition rates, several Machine Learning algorithms are used to recognize three different gestures with the obtained voltage data. To clarify the gesture recognition mechanism, an electrical model of the electrode-skin contact impedance is established. Experimental results show that: rectangular copper electrodes realize the highest recognition rate; the existence of the electrode-skin contact impedance could improve the gesture recognition rate; Medium Gaussian SVM (Support Vector Machine) algorithm is the optimal algorithm with an average recognition rate of 95%.

NBM-T-L-BMX-OS01, Semisynthesized from Osthole, Is a Novel Inhibitor of Histone Deacetylase and Enhances Learning and Memory in Rats.

NBM-T-L-BMX-OS01 (BMX) was derived from the semisynthesis of osthole, isolated from Cnidium monnieri (L.) Cuss., and was identified to be a potent inhibitor of HDAC8. This study shows that HDAC8 is highly expressed in the pancreas and the brain. The function of HDAC8 in the brain has not been adequately studied. Because BMX enhances neurite outgrowth and cAMP response element-binding protein (CREB) activation, the effect of BMX on neural plasticity such as learning and memory is examined. To examine declarative and nondeclarative memory, a water maze, a passive one-way avoidance task, and a novel object recognition task were performed. Results from the water maze revealed that BMX and suberoylanilide-hydroxamic-acid-(SAHA-) treated rats showed shorter escape latency in finding the hidden platform. The BMX-treated animals spent more time in the target quadrant in the probe trial performance. An analysis of the passive one-way avoidance results showed that the BMX-treated animals stayed longer in the illuminated chamber by 1 day and 7 days after footshock. The novel object recognition task revealed that the BMX-treated animals showed a marked increase in the time spent exploring novel objects. Furthermore, BMX ameliorates scopolamine-(Sco-) induced learning and memory impairment in animals, indicating a novel role of BMX in learning and memory.

Chrysin: a histone deacetylase 8 inhibitor with anticancer activity and a suitable candidate for the standardization of Chinese propolis.

Chinese propolis (CP) is a natural product collected by honeybees and a health food raw material. Previous studies have shown that CP exhibits a broad spectrum of biological activities including anticancer, antioxidant, antibacterial, anti-inflammatory, and antiviral activities. The focuses of the present study were the standardization of CP and the possible mechanisms of its active anticancer ingredients. Nine samples of CP were collected from different locations in China. Analyses of the CP samples revealed that all 9 had similar chemical compositions. Parameters analyzed included the CP extract dry weight, total phenolic content, and DPPH free radical scavenging activities. The active anticancer ingredient was isolated, characterized against human MDA-MB-231 breast cancer cells, and identified as chyrsin, a known potent anticancer compound. Chrysin is present at high levels in all 9 of the CP samples, constituting approximately 2.52% to 6.38% of the CP extracts. However, caffeic acid phenethyl ester (CAPE), another potent active ingredient is present in low levels in 9 samples of CP, constituting approximately 0.08% to 1.71% of the CP extracts. Results from analyses of enzymatic activity indicated that chrysin is a histone deacetylase inhibitor (HDACi) and that it markedly inhibited HDAC8 enzymatic activity (EC(50) = 40.2 µM). In vitro analyses demonstrated that chrysin significantly suppressed cell growth and induced differentiation in MDA-MB-231 cells. In a xenograft animal model (MDA-MB-231 cells), orally administered chrysin (90 mg/kg/day) significantly inhibited tumor growth. Despite the geographical diversity of the 9 samples' botanical origins, their chemical compositions and several analyzed parameters were similar, suggesting that CP is standardized, with chrysin being the major active ingredient. Overall, in vitro and in vivo data indicated that chrysin is an HDAC8 inhibitor, which can significantly inhibit tumor growth. Data also suggested that chrysin might represent a suitable candidate for standardization of CP.

NBM-HD-1: A Novel Histone Deacetylase Inhibitor with Anticancer Activity.

HDAC inhibitors (HDACis) have been developed as promising anticancer agents in recent years. In this study, we synthesized and characterized a novel HDACi, termed NBM-HD-1. This agent was derived from the semisynthesis of propolin G, isolated from Taiwanese green propolis (TGP), and was shown to be a potent suppressor of tumor cell growth in human breast cancer cells (MCF-7 and MDA-MB-231) and rat glioma cells (C6), with an IC(50) ranging from 8.5 to 10.3 µM. Western blot demonstrated that levels of p21((Waf1/Cip1)), gelsolin, Ac-histone 4, and Ac-tubulin markedly increased after treatment of cancer cells with NBM-HD-1. After NBM-HD-1 treatment for 1-4 h, p-PTEN and p-AKT levels were markedly decreased. Furthermore, we also found the anticancer activities of NBM-HD-1 in regulating cell cycle regulators. Treatment with NBM-HD-1, p21((Waf1/Cip1)) gene expression had markedly increased while cyclin B1 and D1 gene expressions had markedly decreased. On the other hand, we found that NBM-HD-1 increased the expressions of tumor-suppressor gene p53 in a dose-dependent manner. Finally, we showed that NBM-HD-1 exhibited potent antitumor activity in a xenograft model. In conclusion, this study demonstrated that this compound, NBM-HD-1, is a novel and potent HDACi with anticancer activity in vitro and in vivo.

Ylangene-type and nardosinane-type sesquiterpenoids from the soft corals Lemnalia flava and Paralemnalia thyrsoides.

Chemical investigations of the Formosan soft coral Lemnalia flava have obtained a new ylangene-type sesquiterpenoid, (1S,2S,4R,6S,7R,8S)-4alpha-formyloxy-beta-ylangene (1), along with two known sesquiterpenoids, lemnalol (2) and isolemnalol (3). Three new nardosinane-type sesquiterpenoids, designated as paralemnolins J-L (4-6), and five known sesquiterpenoids (7-11), were isolated from the other soft coral Paralemnalia thyrsoides. The structures of metabolites 1 and 4-6 were elucidated through extensive spectroscopic analysis and chemical methods. Moreover, the anti-inflammatory activity of metabolites 1-7 and 11 was evaluated in vitro.