Xiangfang Zeng

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Probiotics are living microorganisms that provide a wide variety of health benefits to the host when ingested in adequate amounts. The bacterial strains most frequently used as probiotic agents are lactic acid bacteria, such as Lactobacillus reuteri, which is one of the few endogenous Lactobacillus species found in the gastrointestinal tract of vertebrates,(More)
Tight junctions (TJs) maintain the intestinal mucosal barrier, dysfunction of which plays a vital role in the pathophysiology of a variety of gastrointestinal disorders. Previously, we have shown that L. reuteri I5007 maintained the gut epithelial barrier in newborn piglets. Here we aimed to decipher the influence of L. reuteri I5007 on tight junction (TJ)(More)
Dietary modulation of the synthesis of endogenous host defense peptides (HDPs) represents a novel antimicrobial approach for disease control and prevention, particularly against antibiotic-resistant infections. However, HDP regulation by dietary compounds such as butyrate is species-dependent. To examine whether butyrate could induce HDP expression in pigs,(More)
We apply phase-weighted stacking (PWS) to the analysis of lowfrequency earthquakes (LFEs) in the Parkfield, California, region and central Cascadia. The technique uses the coherence of the instantaneous phase among the stacked signals to enhance the signal-to-noise ratio (SNR) of the stack. We find that for picking LFE arrivals for the Parkfield,(More)
Threonine is the second or third limiting amino acid in swine or poultry diets. This nutrient plays a critical role in the maintenance of intestinal mucosal integrity and barrier function, which can be indicated by intestinal morphology, mucus production (number of goblet cells), transepithelial permeability, brush border enzyme activity, and growth(More)
Leptin plays a critical role in regulating muscle protein metabolism by binding with leptin receptors in a 1:1 stoichiometry. However, the role for leucine in the regulation of leptin receptor expression in muscle has not been investigated. The present study was conducted to test the hypothesis that leucine regulates leptin receptor levels in C2C12(More)
N-carbamylglutamate (NCG) has been shown to enhance performance in neonatal piglets. However, few studies have demonstrated the effect of NCG on the intestinal mucosal barrier. This study was conducted to determine the effects of dietary NCG supplementation on intestinal mucosal immunity in neonatal piglets after an Escherichia coli (E. coli) challenge.(More)
Nutritional induction of endogenous antimicrobial peptide expression is considered a promising approach to inhibit the outgrowth and infection of pathogenic microbes in mammals. The present study investigated possible regulation of porcine epithelial β-defensins in response to branched-chain amino acids (BCAA) in vivo and in vitro. BCAA treatment increased(More)
Four experiments were conducted with 120 pregnant Sprague-Dawley rats to determine effects of dietary arginine supplementation on embryonic survival. Rats were fed a nonpurified diet supplemented with 1.3% (wt:wt) L-arginine-HCl or 2.2% (wt:wt) L-alanine (isonitrogenous control) throughout pregnancy (Expt. 1), between d 1 and 7 of gestation and then the(More)