Tributyrin Supplementation Protects Immune Responses and Vasculature and Reduces Oxidative Stress in the Proximal Colon of Mice Exposed to Chronic-Binge Ethanol Feeding.

Excessive ethanol consumption causes adverse effects and contributes to organ dysfunction. Ethanol metabolism triggers oxidative stress, altered immune function, and gut dysbiosis. The gut microbiome is known to contribute to the maintenance of intestinal homeostasis, and disturbances are associated with pathology. A consequence of gut dysbiosis is also alterations in its metabolic and fermentation byproducts. The gut microbiota ferments undigested dietary polysaccharides to yield short-chain fatty acids, predominantly acetate, propionate, and butyrate. Butyrate has many biological mechanisms of action including anti-inflammatory and immunoprotective effects, and its depletion is associated with intestinal injury. We previously showed that butyrate protects gut-liver injury during ethanol exposure. While the intestine is the largest immune organ in the body, little is known regarding the effects of ethanol on intestinal immune function. This work is aimed at investigating the effects of butyrate supplementation, in the form of the structured triglyceride tributyrin, on intestinal innate immune responses and oxidative stress following chronic-binge ethanol exposure in mice. Our work suggests that tributyrin supplementation preserved immune responses and reduced oxidative stress in the proximal colon during chronic-binge ethanol exposure. Our results also indicate a possible involvement of tributyrin in maintaining the integrity of intestinal villi vasculature disrupted by chronic-binge ethanol exposure.

Star formation inside a galactic outflow.

Recent observations have revealed massive galactic molecular outflows that may have the physical conditions (high gas densities) required to form stars. Indeed, several recent models predict that such massive outflows may ignite star formation within the outflow itself. This star-formation mode, in which stars form with high radial velocities, could contribute to the morphological evolution of galaxies, to the evolution in size and velocity dispersion of the spheroidal component of galaxies, and would contribute to the population of high-velocity stars, which could even escape the galaxy. Such star formation could provide in situ chemical enrichment of the circumgalactic and intergalactic medium (through supernova explosions of young stars on large orbits), and some models also predict it to contribute substantially to the star-formation rate observed in distant galaxies. Although there exists observational evidence for star formation triggered by outflows or jets into their host galaxy, as a consequence of gas compression, evidence for star formation occurring within galactic outflows is still missing. Here we report spectroscopic observations that unambiguously reveal star formation occurring in a galactic outflow at a redshift of 0.0448. The inferred star-formation rate in the outflow is larger than 15 solar masses per year. Star formation may also be occurring in other galactic outflows, but may have been missed by previous observations owing to the lack of adequate diagnostics.

Galaxy evolution. Evidence for mature bulges and an inside-out quenching phase 3 billion years after the Big Bang.

Most present-day galaxies with stellar masses ≥10(11) solar masses show no ongoing star formation and are dense spheroids. Ten billion years ago, similarly massive galaxies were typically forming stars at rates of hundreds solar masses per year. It is debated how star formation ceased, on which time scales, and how this "quenching" relates to the emergence of dense spheroids. We measured stellar mass and star-formation rate surface density distributions in star-forming galaxies at redshift 2.2 with ~1-kiloparsec resolution. We find that, in the most massive galaxies, star formation is quenched from the inside out, on time scales less than 1 billion years in the inner regions, up to a few billion years in the outer disks. These galaxies sustain high star-formation activity at large radii, while hosting fully grown and already quenched bulges in their cores.

Gas accretion as the origin of chemical abundance gradients in distant galaxies.

It has recently been suggested that galaxies in the early Universe could have grown through the accretion of cold gas, and that this may have been the main driver of star formation and stellar mass growth. Because the cold gas is essentially primordial, it has a very low abundance of elements heavier than helium (referred to as metallicity). If funnelled to the centre of a galaxy, it will result in the central gas having an overall lower metallicity than gas further from the centre, because the gas further out has been enriched by supernovae and stellar winds, and not diluted by the primordial gas. Here we report chemical abundances across three rotationally supported star-forming galaxies at redshift z ≈ 3, only 2 Gyr after the Big Bang. We find 'inverse' gradients, with the central, star-forming regions having lower metallicities than less active ones, which is opposite to what is seen in local galaxies. We conclude that the central gas has been diluted by the accretion of primordial gas, as predicted by 'cold flow' models.

The clear liquid diet is no longer a necessity in the routine postoperative management of surgical patients.

The reinstitution of oral intake in patients who have undergone intra-abdominal surgery has traditionally progressed in a stepwise fashion. Various retrospective studies and anecdotal reports have suggested that a "regular" diet as the first postoperative meal is well tolerated. Although clear liquids are accepted as the standard first postoperative meal, there appears to be little scientific data to support their use. The current study was undertaken to determine whether there is any difference in tolerance to clear liquids versus a regular diet as the first postoperative oral intake. This study is not intended to suggest that clear liquid diets harm patients but to attempt to support our hypothesis that a regular diet as the first postoperative meal is not associated with and increased morbidity. A total of 241 patients undergoing abdominal operations were prospectively randomized to receive either routine clear liquids (N=135) or regular diet (N=106) as the first oral intake. They were followed for any symptoms or signs of dietary intolerance. The group receiving a regular diet was not found to have any statistically significant increase in dietary intolerance in comparison with the clear liquid group. Nutritional data collected in a subset of patients revealed a higher caloric intake in those assigned to a regular diet. These results suggest that the routine use of clear liquids as the initial postoperative diet may be unnecessary and nutritionally suboptimal when compared with a regular diet.

[24-hour blood pressure: effects of sports in aged subjects]. / La pressione arteriosa di 24-h: effetto dello sport in soggetti anziani.

The present study deals with the blood pressure (BP) and heart rate (HR) 24-h pattern in aged people of both sexes ranging in age from 66 to 75 years. 20 subjects were active in agonistic sports (running and swimming), 20 others had sedentary habits. BP and HR were studied by non-invasive monitoring along with chronobiometric analysis. The BP and HR 24-h pattern was seen to preserve its circadian rhythm in both aged athletes and sedentary elderly. The analysis reveals that the aged athletes show a higher mesor for systolic BP and a lower mesor for diastolic BP and HR. The daily pressure load, as the integral of the BP 24-h values multiplied by the HR mesor, is lower in aged people practising sport as compared to age-matched individuals with sedentary habits. The spectral analysis reveals that physical exercise acts to change the time structure of BP and HR 24-h patterns. The conclusion is drawn that active sport plays beneficial effects in aged people because of a lower pressure load.