Environmental pH signals the release of monosaccharides from cell wall in coral symbiotic alga.

Reef-building corals thrive in oligotrophic environments due to their possession of endosymbiotic algae. Confined to the low pH interior of the symbiosome within the cell, the algal symbiont provides the coral host with photosynthetically fixed carbon. However, it remains unknown how carbon is released from the algal symbiont for uptake by the host.

Convergent evolution of nitrogen-adding enzymes in the purine nucleotide biosynthetic pathway, based on structural analysis of adenylosuccinate synthetase (PurA).

Adenylosuccinate synthetase (PurA) is an enzyme responsible for the nitrogen addition to inosine monophosphate (IMP) by aspartate in the purine nucleotide biosynthetic pathway. And after which the fumarate is removed by adenylosuccinate lyase (PurB), leaving an amino group. There are two other enzymes that catalyze aspartate addition reactions similar to PurA, one in the purine nucleotide biosynthetic pathway (SAICAR synthetase, PurC) and the other in the arginine biosynthetic pathway (argininosuccinate sythetase, ArgG).

Defining an orbitofrontal compass: Functional and anatomical heterogeneity across anterior-posterior and medial-lateral axes.

The orbitofrontal cortex (OFC) plays a critical role in the flexible control of behaviors and has been the focus of increasing research interest. However, there have been a number of controversies around the exact theoretical role of the OFC. One potential source of these issues is the comparison of evidence from different studies, particularly across species, which focus on different specific sub-regions within the OFC.

Sex Differences in Risk Preference and c-Fos Expression in Paraventricular Thalamic Nucleus of Rats During Gambling Task.

Different biological requirements between males and females may cause sex differences in decision preference when choosing between taking a risk to get a higher gain or taking a lower but sure gain. Several studies have tested this assumption in rats, however the conclusion remains controversial because the previous real-world like gambling tasks contained a learning component to track a global payoff of probabilistic outcome in addition to risk preference. Therefore, we modified a simple gambling task allowing us to exclude such learning effect, and investigated the sex difference in risk preference of rats and its neural basis.

Dopaminergic and serotonergic modulation of anterior insular and orbitofrontal cortex function in risky decision making.

Systemic manipulations have shown that dopamine and serotonin systems are involved in risky decision making. However, how they work within the regions that implement risky choices remains unclear. The present study investigated the role of dopamine and serotonin in the rat anterior insular cortex (AIC) and orbitofrontal cortex (OFC), which make different contributions to risky decision making.

[Risk taking and the insular cortex].

Risk taking can lead to ruin, but sometimes, it can also provide great success. How does our brain make a decision on whether to take a risk or to play it safe? Recent studies have revealed the neural basis of risky decision making. In this review, we focus on the role of the anterior insular cortex (AIC) in risky decision making.

Inactivating anterior insular cortex reduces risk taking.

We often have to make risky decisions between alternatives with outcomes that can be better or worse than the outcomes of safer alternatives. Although previous studies have implicated various brain regions in risky decision making, it remains unknown which regions are crucial for balancing whether to take a risk or play it safe. Here, we focused on the anterior insular cortex (AIC), the causal involvement of which in risky decision making is still unclear, although human imaging studies have reported AIC activation in various gambling tasks.

Case of inflammatory fibroid polyp of the esophagogastric junction.

Upper gastrointestinal endoscopy of a 25-year-old man with heartburn revealed an elevated lesion in the esophagogastric junction (EGJ). Piecemeal endoscopic mucosal resection (EMR) followed by histopathological examination led to a diagnosis of inflammatory fibroid polyp (IFP). After EMR, the heartburn persisted despite giving a proton pump inhibitor (PPI), and the residual lesion gradually enlarged and a transverse mucosal break developed on the esophageal side of it.

Refractory diverticular colitis with progressive ulcerative colitis-like changes extending to the rectum.

A 68-year-old man visited our department because of diarrhea and bloody stools. Colonoscopy revealed diverticula scattered in the sigmoid colon with localized mucosal edema and reddening. The mucosa became somewhat rough 9 months later, and had an erosive, ulcerative colitis (UC)-like appearance after a further 6 months, with these changes extending to the rectum.

[A case of Cronkhite-Canada syndrome in which contrast radiologic examinations of the digestive tract were performed at the time of development of the clinical symptoms].

We encountered a case of Cronkhite-Canada syndrome in which contrast radiologic examinations of the upper and lower digestive tract were performed immediately before and after the development of the clinical symptoms. These contrast radiologic images showed mainly mucosal coarseness and no polyposis of the stomach and colon. The endoscopy, performed 3 months later from the development of the clinical symptoms, revealed polyposis of the stomach and colon.