Isolation of new indole alkaloid triglucoside from the aqueous extract of Uncaria rhynchophylla.

Uncaria rhynchophylla (Miq.) Miq. (Rubiaceae) is widely used as a botanical raw material for traditional Japanese and Chinese medicines. However, not all of its potentially bioactive constituents have been isolated and characterized. Herein, one new indole alkaloid triglucoside (1), nine known alkaloids (2-10) and thirteen known non-alkaloids (11-23) were isolated from the aqueous extract of Uncaria rhynchophylla hook and structurally characterized 1H and 13C NMR and high-resolution electrospray ionization mass spectrometry. The absolute configurations of isolated compounds (1, 2 and 3) were determined by the X-ray diffraction analysis of their single crystals obtained using a micro-drop crystallization technique. This technique allows single crystals to be obtained from samples as small as 50 µg, thus providing detailed structural information even on minor constituents and enabling the accurate quality monitoring of botanical raw materials more accurately.

Ruthenium-Catalyzed Ortho C-H Arylation of Aromatic Nitriles with Arylboronates and Observation of Partial Para Arylation.

Ruthenium-catalyzed C-H arylation of aromatic nitriles with arylboronates is described. The use of RuH2(CO){P(4-MeC6H4)3}3 as a catalyst provided higher yields of the ortho arylation products than the conventional RuH2(CO)(PPh3)3 catalyst. The arylation takes place mostly at the ortho positions, but unprecedented para arylation was also partially observed to give ortho,para diarylation products. In addition to C-H bond cleavage, the cyano group was also found to function as a directing group for cleavage of C-O bonds in aryl ethers.

The neural basis of dishonest decisions that serve to harm or help the target.

We conducted a functional magnetic resonance imaging (fMRI) study to elucidate the neurocognitive mechanisms of harmful and helpful dishonest decisions. During scanning, the subjects read scenarios concerning events that could occur in real-life situations and were asked to decide whether to tell a lie as though they were experiencing those events. Half of the scenarios consisted of harmful stories in which the dishonest decisions could be regarded as bad lies, and the other half consisted of helpful stories in which the dishonest decisions could be regarded as good lies. In contrast to the control decision-making task, we found that the decision-making tasks that involved honesty or dishonesty recruited a network of brain regions that included the left dorsolateral prefrontal cortex. In the harmful stories, the right temporoparietal junction and the right medial frontal cortex were activated when the subjects made dishonest decisions compared with honest decisions. No region discriminated between the honest and dishonest decisions made in the helpful stories. These preliminary findings suggest that the neural basis of dishonest decisions is modulated by whether the lying serves to harm or help the target.

Dissociable neural systems for moral judgment of anti- and pro-social lying.

Pro-social lying, which serves to benefit listeners, is considered more socially and morally acceptable than anti-social lying, which serves to harm listeners. However, it is still unclear whether the neural mechanisms underlying the moral judgment of pro-social lying differ from those underlying the moral judgment of anti-social lying. We used functional magnetic resonance imaging (fMRI) to examine the neural activities associated with moral judgment in anti- and pro-social lying. During fMRI scanning, subjects were provided with scenarios describing a protagonist's anti- and pro-social lying and were then asked to judge whether the protagonist's act was morally appropriate. The behavioral data showed that anti-social lying was mostly judged to be morally inappropriate and that pro-social lying was mainly judged to be morally appropriate. The functional imaging data revealed dissociable neural systems for moral judgment in anti- and pro-social lying. The anti-social lying, which was judged to be morally inappropriate, was associated with increased activity in the right ventromedial prefrontal cortex, right middle frontal gyrus, right precuneus/posterior cingulate gyrus, left posterior cingulate gyrus, and bilateral temporoparietal junction when compared with the control condition. The pro-social lying, which was judged to be morally appropriate, was associated with increased activity in the right middle temporal gyrus, right supramarginal gyrus, and the left middle cingulate gyrus when compared with the control condition. No overlapping activity was observed during the moral judgment of anti- and pro-social lying. Our data suggest that cognitive and neural processes for the moral judgment of lying are modulated by whether the lie serves to harm or benefit listeners.

Neural basis of pleasant and unpleasant emotions induced by social reputation.

We used positron emission tomography to identify brain regions involved in the processing of emotions induced by social reputation from others. During positron emission tomographic scanning, individuals were presented with either a positive or a negative social reputation combined with face photographs of persons whom the individuals either liked or disliked. Behavioral results revealed that a positive reputation led to a higher pleasantness score than a negative reputation. Imaging data demonstrated that the orbitofrontal cortex was activated with positive reputations relative to negative reputations, and that the amygdala was activated with negative reputations relative to positive reputations. These findings suggest that pleasant and unpleasant emotions induced by positive and negative social reputations from others are associated with activity in different brain regions.

The role of the dorsolateral prefrontal cortex in deception when remembering neutral and emotional events.

We used functional magnetic resonance imaging (fMRI) to investigate the neural correlates of deception while remembering neutral events and emotional events. Before fMRI, subjects were presented with a series of neutral and emotional pictures and were asked to rate each picture for arousal. During fMRI, subjects were presented with the studied and nonstudied pictures and were asked to make an honest recognition judgment in response to half of the pictures and a dishonest response to the remaining half. We found that deception pertaining to the memory of neutral pictures was associated with increased activity in the bilateral dorsolateral prefrontal cortex, the left ventrolateral prefrontal cortex, and the left orbitofrontal cortex. We also found that deception while remembering emotional pictures was associated with increased activity in the bilateral dorsolateral prefrontal cortex. An overlapping activation between the two types of deception was found in the bilateral dorsolateral prefrontal cortex. Our results indicate that the dorsolateral prefrontal cortex is associated with the executive aspects of deception, regardless of the emotional valence of memory content.