This study was to evaluate the effects of supplementation of AA form (crystalline vs. protein bound) in low-protein diets on growth, metabolic, and immunological characteristics of pigs. A total of 80 barrows (PIC 327 × 1050; 15.57 ± 0.13 kg BW and 48 ± 2 d of age), housed in 4 pigs per pen with 5 pens per treatment, were assigned to 4 dietary treatments of 17, 15, and 13% CP and 13% CP plus casein for 28 d. The crystalline AA were supplemented to meet the requirement of indispensable AA in pigs. Results showed that pigs fed the 13% CP diet or the 13% CP plus casein diet had lower ( < 0.01) ADG and ADFI and a greater ( < 0.01) feed:gain ratio than pigs fed the 17% CP or 15% CP diets over the 4-wk study period. Compared with other diets, pigs fed the 13% CP diet had decreased concentrations of plasma urea nitrogen, albumin ( < 0.01), and mRNA expressions of Toll-like receptor 4 (), nuclear factor kappa B (; < 0.05), and Toll-interacting protein (; < 0.01) in the ileum and also increased activity of plasma glutamate-pyruvate transaminase ( < 0.05) and concentrations of IL-1β ( < 0.05) and tumor necrosis factor-α ( < 0.01); however, these characteristics were partly normalized by feeding the 13% CP plus casein diet. Furthermore, the plasma concentration of insulin-like growth factor 1 (IGF-1; < 0.01) and mRNA expressions of protein kinase B (), mammalian target of rapamycin (), and ribosomal protein S6 kinase () in longissimus muscle were increased ( < 0.05) in pigs fed the 13% CP plus casein diet relative to pigs fed the 17% CP or 15% CP diets. In summary, reducing dietary CP level from 17% to 15% had no effect on growth, metabolic, and immunological characteristics of 15- to 35-kg pigs. A further reduction of dietary CP level up to 13% would lead to poor growth performance, but metabolic and immunological characteristics were partly normalized using protein-bound AA to replace synthesized AA in the 13% CP diet.

The development of natural antimicrobial agents offers new strategies for food preservation due to the health hazards associated with the spoilage of meat products caused by microbial contamination. In this paper, the inhibitory mechanism of protocatechualdehyde (PCA) on Listeria monocytogenes was described, and its effect on the preservation of cooked chicken breast was evaluated. The results showed that the minimal inhibitory concentration (MIC) of PCA on L. monocytogenes was 0.625 mg/mL. Secondly, PCA destroyed the integrity of the L. monocytogenes cell membrane, which was manifested as a decrease in membrane hyperpolarization, intracellular ATP level, and intracellular pH value. Field emission gun scanning electron microscopy (FEG-SEM) observed a cell membrane rupture. Transcriptome analysis showed that PCA may inhibit cell growth by affecting amino acid, nucleotide metabolism, energy metabolism, and the cell membrane of L. monocytogenes. Additionally, it was discovered that PCA enhanced the color and texture of cooked chicken breast meat while decreasing the level of thiobarbituric acid active substance (TBARS). In conclusion, PCA as a natural antibacterial agent has a certain reference value in extending the shelf life of cooked chicken breast.

Background: To evaluate the predictive value at the hepatobiliary phase (HBP) magnetic resonance imaging (MRI) after gadobenate dimeglumine (Gd-BOPTA) injection for histologic grades of hepatocellular carcinoma (HCC). Materials and Methods: HCC patients who underwent Gd-BOPTA-enhanced MRI were analyzed and divided into four histologic grades of differentiation based on Edmonson-Steiner grade. Besides, HCC tumor differentiations grade I, II and III, IVwere defined as well-differentiated (WD), moderatelydifferentiated (MD), poorly-differentiated (PD), respectively. The clinical, pathological and imaging features of patients were assessed. Receiver operating characteristic (ROC) curve was to evaluate the significance between WD/MD HCC and PD HCC using the apparent diffusion coefficient (ADC), relative intensity ratio (RIR) of T1WI and T2WI (T1RIR, T2RIR), contrastenhancement ratio in arterial phase (CERA) and contrast-noise-ratio (CNR) in HBP (CNR hbp ). Results: A total of 102 HCC patients were analyzed (grade I, n=19; grade II, n=30; grade III, n=30; grade IV, n=23). There was no statistical difference regarding to the pathological and clinical features among four grades. There were significant differences in CERA, CNR hbp , T1RIR, T2RIR and ADC values among the four HCC grades (all P<0.05). Based on ROC curve, comparison of the five quantitative MRI parameters indicated ADC (sensitivity 84.8%, specificity 82.6%, AUC 0.862) and CNR hbp value (sensitivity 78.5%, specificity 91.3%, AUC 0.916) could significantly distinguish the HCC histological grade. Conclusions: The ADC and/or CNR hbp value in HBP-MRI after GD-BOPTA injection might be as the significant quantitative parameters to distinguish HCC histological grade.