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Protein is most commonly consumed as whole foods as opposed to single nutrients. However, the food matrix regulation of the postprandial muscle protein synthetic response has received little attention.

The prebiotic fiber inulin has been studied in individuals undergoing hemodialysis (HD) due to its ability to reduce gut microbiota-derived uremic toxins. However, studies examining the effects of inulin on the gut microbiota and derived metabolites are limited in these patients. We aimed to assess the impact of a 4-week supplementation of inulin on the gut microbiota composition and microbial metabolites of patients on HD.

Despite its importance in poultry research, there is lack of standardized and practical techniques to measure intestinal permeability in a noninvasive manner. Therefore, this research sought to standardize a procedure using lactulose (Lac) and mannitol (Man) to measure intestinal barrier function in broilers. Twenty-one-day-old male and female Ross 308 birds were orally gavaged (either 2 mL/kg BW or fixed 3 mL per bird) with a solution containing 5 to 25 g Lac and 1 to 5 g Man dissolved in pure water to reach 100 mL of final solution. Feed withdrawal (FW; 2–24-h duration) prior to dosing with Lac and Man (LacMan) was mainly used to induce graded intestinal permeability. Blood samples were collected at 60-, 90-, or 120-min after LacMan dosing using serum or plasma (K2EDTA and/or Na-Heparin) blood tubes. Lac and Man concentrations were quantified by HPLC. Plasma samples collected 90-min after LacMan dosing elicited the least variable response (22.4% vs. 22.8% or 23.4% CV when compared with 60- and 120-min sampling time-points, respectively), and both markers were detectable after administering a solution containing the lowest concentration of Lac and Man. However, analytical problems arose when using Na-Heparin anticoagulant as high glucose levels interfered with Lac quantification. Upon improving the chromatographic technique, it became evident that a 24-h FW increased (P< 0.01) Lac concentrations. In the last trial, a more severe glucose interference was observed, resulting in no Lac detection within an entire treatment group. Twelve hours of FW increased (P< 0.01) Man concentration in the plasma of birds receiving the solution containing 3 g Man, but had no effect on the birds receiving the solution containing 5 g Man. A 24-h FW did not affect the Man concentrations in birds receiving the solution containing either 3 or 5 g Man. With inconsistency of Lac detection throughout our trials, it was concluded that the combination of Lac and Man is an unreliable marker to predict intestinal barrier function in broilers.

The objective of this research was to measure in vitro hydrolytic digestion characteristics, glycemic and insulinemic responses, and true metabolizable energy (TMEn) content of select soluble fiber dextrins (SFDs) and pullulans. The SFDs were derived either from tapioca starch or from corn starch. The pullulans were of low, intermediate, and high molecular weight. Soluble fiber dextrins varied in digestibility, with all substrates resulting in low to intermediate in vitro monosaccharide digestion. Pullulans were nearly completely hydrolyzed after simulated hydrolytic digestion. The glycemic response with dogs varied widely among SFDs, with all but one SFD substrate having lower glycemic response than maltodextrin (Malt). The pullulans all resulted in low glycemic values. Lower relative insulinemic responses (RIR) compared to the Malt control were noted for all SFDs and pullulans. True metabolizable energy (TMEn) values for SFDs obtained using roosters were lower than for Malt, with tapioca-based SFDs having numerically higher values than corn-based SFDs. Pullulans resulted in higher TMEnvalues than did SFDs. Soluble fiber dextrins and pullulans may be suitable candidates for reduced calorie and glycemic foodstuffs.

Digestibility is a primary factor in determining the quality of dietary protein. Microbial protease supplementation may be a strategy for improving protein digestion and subsequent postprandial plasma amino acid availability.

Live attenuated vaccines are generally highly efficacious and often superior to inactivated vaccines, yet the underlying mechanisms of this remain largely unclear. Here we identify recognition of microbial viability as a potent stimulus for follicular helper T cell (TFHcell) differentiation and vaccine responses. Antigen-presenting cells (APCs) distinguished viable bacteria from dead bacteria through Toll-like receptor 8 (TLR8)-dependent detection of bacterial RNA. In contrast to dead bacteria and other TLR ligands, live bacteria, bacterial RNA and synthetic TLR8 agonists induced a specific cytokine profile in human and porcine APCs, thereby promoting TFHcell differentiation. In domestic pigs, immunization with a live bacterial vaccine induced robust TFHcell and antibody responses, but immunization with its heat-killed counterpart did not. Finally, a hypermorphic TLR8polymorphism was associated with protective immunity elicited by vaccination with bacillus Calmette-Guérin (BCG) in a human cohort. We have thus identified TLR8 as an important driver of TFHcell differentiation and a promising target for TFHcell–skewing vaccine adjuvants.

Nontargeted metabolomics analyses were used (1) to compare fecal metabolite profiles of healthy breast-fed (BF) and formula-fed (FF) infants before and during in vitro fermentation in batch culture and (2) to evaluate fecal metabolomics in assessing infant diet. Samples from healthy BF (n= 4) or FF (n= 4) infants were individually incubated at 37°C in anaerobic media containing 1% (wt/vol) galactooligosaccharides, 6′-sialyllactose, 2′-fucosyllactose, lacto-N-neotetraose, inulin, and gum arabic for up to 6 h, and supernatants were analyzed using GC/MS and LC/MS/MS to assess changes in various compounds. Comparison of over 250 metabolites prior to incubation showed that BF samples contained higher relative concentrations (P≤ 0.05) of 14 compounds including human milk oligosaccharides and other metabolites presumably transferred through breast feeding (linoelaidate, myo-inositol) (P≤ 0.05). Conversely, feces from FF infants contained 41 identified metabolites at higher levels (P≤ 0.05) with many indicative of carbon limitation and protein fermentation. Our data are consistent with the notion that carbon-limited cultures catabolize protein and amino acids to obtain energy, whereas the provision of fermentable carbohydrate creates anabolic conditions relying on amino acids for bacterial growth. Results also suggest that fecal metabolomics can be a useful tool for studying interactions among diet, microbes, and host.

This review describes recent advances in nanomaterials fabrication that have led to the synthesis of high aspect ratio particles on nanometer length scales. The elongated structure of these materials often result in inherent chemical, electrical, magnetic, and optical anisotropy that can be exploited for interactions with cells and biomolecules in fundamentally new ways. We briefly describe the synthetic procedures that have been developed to fabricate nanorods, nanowires, and nanotubes. We summarize literature reports that describe the use of high aspect ratio nanoparticles for biological sensing, separations, and gene delivery. We emphasize the recent discovery of single nanowire field-effect transistors that may revolutionize biological sensing and yield extremely low detection limits. Separations technology with chemically modifiable nanotube membranes and with magnetic nanowires that can be tailored to selectively interact with molecules of interest is also described. Other areas of biotechnology that have been improved by the integration of high aspect ratio nanoparticles are also described.

The article reviews the web site www.socalhort.org from the Southern California Horticultural Society.