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To investigate the cumulative effects of maternal supplementation with nucleotides in the form of uridine (UR) on fatty acid and amino acid constituents of neonatal piglets, fifty-two sows in late gestation were assigned randomly into the control (CON) group (fed a basal diet) or UR group (fed a basal diet with 150 g/t UR). Samples of neonates were collected during farrowing. Results showed that supplementing with UR in sows’ diet significantly decreased the birth mortality of pigs (P = 0·05), and increased serum total cholesterol, HDL and LDL of neonatal piglets (P < 0·05). Moreover, the amino acid profile of serum and liver of neonatal piglets was affected by the addition of UR in sows’ diets (P < 0·05). Furthermore, an up-regulation of mRNA expression of energy metabolism-related genes, including fatty acid elongase 5, fatty acid desaturase 1, hormone-sensitive lipase and cholesterol-7a-hydroxylase, was observed in the liver of neonates from the UR group. Additionally, a decrease in placental gene expression of excitatory amino acid transporters 2, excitatory amino acid transporter 3 and neutral AA transporter 1 in the UR group was concurrently observed (P < 0·05), and higher protein expression of phosphorylated protein kinase B, raptor, PPARα and PPARγ in placenta from the UR group was also observed (P < 0·05). Together, these results showed that maternal UR supplementation could regulate placental nutrient transport, largely in response to an alteration of mTORC1–PPAR signalling, thus regulating the nutrition metabolism of neonatal piglets and improving reproductive performance.
The present study was conducted to evaluate the effects of glucose, soya oil or glutamine on jejunal morphology, protein metabolism and protein expression of the mammalian target of rapamycin complex 1 (mTORC1) signalling pathway in jejunal villus or crypt compartment of piglets. Forty-two 21 d-weaned piglets were randomly allotted to one of the three isoenergetic diets formulated with glucose, soya oil or glutamine for 28 d. On day 14 or 28, the proteins in crypt enterocytes were analysed with isobaric tags for relative and absolute quantification and proteins involved in mTORC1 signalling pathway in villus or crypt compartment cells were determined by Western blotting. Our results showed no significant differences (P > 0·05) in jejunal morphology among the three treatments on day 14 or 28. The differentially expressed proteins mainly took part in a few network pathways, including antimicrobial or inflammatory response, cell death and survival, digestive system development and function and carbohydrate metabolism. On day 14 or 28, there were higher protein expression of eukaryotic initiation factor-4E binding protein-1 in jejunal crypt compartment of piglets supplemented with glucose or glutamine compared with soya oil. On day 28, higher protein expression of phosphor-mTOR in crypt compartment was observed in piglets supplemented with glucose compared with the soya oil. In conclusion, the isoenergetic glucose, soya oil or glutamine did not affect the jejunal morphology of piglets; however, they had different effects on the protein metabolism in crypt compartment. Compared with soya oil, glucose or glutamine may be better energy supplies for enterocytes in jejunal crypt compartment.
Ethanolamine (Etn) contained in milk is the base constituent of phosphatidylethanolamine and is required for the proliferation of intestinal epithelial cells and bacteria, which is important for maintenance of the gut microbiome and intestinal development. The present study investigated the effect of Etn on intestinal function and microbiome using 21-d-old Sprague–Dawley rats treated with 0, 250, 500 and 1000 μm Etn in drinking water for 2 weeks immediately after weaning. Growth performance, intestinal morphology, antioxidant capacity and mucosal immunity, as well as gut microbiota community composition, were evaluated. Metagenomic prediction and metabolic phenotype analysis based on 16S RNA sequencing were also carried out to assess changes in metabolic functions. We found that weaned rats administered 500 μm Etn enhanced mucosal antioxidant capacity, as evidenced by higher superoxide dismutase and glutathione peroxidase levels in the jejunum (P<0·05) compared with those in the control group. Predominant microbes including Bacteroidetes, Proteobacteria, Elusimicrobia and Tenericutes were altered by different levels of Etn compared with the control group. An Etn concentration of 500 µm shifted colonic microbial metabolic functions that are in favour of lipid- and sugar-related metabolism and biosynthesis. Etn also altered the metabolic phenotypes such as anaerobic microbial counts, and oxidative stress tolerance at over 250 µm. This is the first report for a role of Etn in modifying gut microbiota and intestinal functions. Our findings highlighted the important role of Etn in shaping gut microbial community and promotes intestinal functions, which may provide a better insight of breast-feeding to infant’s gut health.
We examined the in vitro developmental competence of parthenogenetic activation (PA) oocytes activated by an electric pulse (EP) and treated with various concentrations of AZD5438 for 4 h. Treatment with 10 µM AZD5438 for 4 h significantly improved the blastocyst formation rate of PA oocytes in comparison with 0, 20, or 50 µM AZD5438 treatment (46.4% vs. 34.5%, 32.3%, and 24.0%, respectively; P < 0.05). The blastocyst formation rate was higher in the group treated with AZD5438 for 4 h than in the groups treated with AZD5438 for 2 or 6 h (42.8% vs. 38.6% and 37.2%, respectively; P > 0.05). Furthermore, 66.67% of blastocysts derived from these AZD5438-treated PA oocytes had a diploid karyotype. The blastocyst formation rate of PA and somatic cell nuclear transfer (SCNT) embryos was similar between oocytes activated by an EP and treated with 2 mM 6-dimethylaminopurine for 4 h and those activated by an EP and treated with 10 µM AZD5438 for 4 h (11.11% vs. 13.40%, P > 0.05). In addition, the level of maturation-promoting factor (MPF) was significantly decreased in oocytes activated by an EP and treated with 10 µM AZD5438 for 4 h. Finally, the mRNA expression levels of apoptosis-related genes (Bax and Bcl-2) and pluripotency-related genes (Oct4, Nanog, and Sox2) were checked by RT-PCR; however, there were no differences between the AZD5438-treated and non-treated control groups. Our results demonstrate that porcine oocyte activation via an EP in combination with AZD5438 treatment can lead to a high blastocyst formation rate in PA and SCNT experiments.
Structural distortions at the nanoscale are delicately linked with many exotic properties for ferroic thin films. Based on advanced aberration corrected scanning transmission electron microscopy, we observe BiFeO3 thin films with variant tensile strain states and demonstrate at an atomic scale the interplay of intrinsic spontaneous structural distortions with external constraints. Structural parameters (the rhombohedral distortion and domain wall shear distortion) under zero (BiFeO3/GdScO3) and 1.5% (BiFeO3/PrScO3) lateral strain states are quantitatively analyzed which are suppressed within a few unit cells near the film/substrate interfaces. In particular, an interfacial layer with asymmetrical lattice distortions (enhanced and reduced out-of-plane lattice spacing) on the two sides of 109° domain wall is resolved. These structural distortions near the film/substrate interface in ferroic thin films reveal intense tanglement of intrinsic distortions of BiFeO3 with external boundary conditions, which could provide new insights for the development of nanoscale ferroelectric devices.
Intense broad absorption bands centered around 1.7, 2.5, 3.1, and 3.7 eV take place in Er3+-diffused layer formed near MgO (5 mol%)-doped LiNbO3 crystal surface by in-diffusion of Er metal under Li-poor atmosphere. These bands are tentatively attributed to the defect absorption of small polarons, bipolarons, F-centers, and Q-polarons created due to Er3+ in-diffusion and Li2O loss from the crystal. It is interesting that the number, type, area, and peaking position of the bands can be controlled by the diffusion temperature and further oxidation treatment. Such material is a promising medium for data storage based upon two-color holography.
Locally Er3+-doped noncongruent, Li-deficient Ti:Er:LiNbO3 strip waveguide was fabricated with a technological process in sequence of preparation of Li-deficient LiNbO3 substrate using Li-poor vapor transport equilibration (VTE), Er3+, and Ti4+ diffusion in wet O2. The Li2O content change was evaluated from the measured birefringence. The Ti4+ and Er3+ profile characteristics in the waveguide were studied by secondary ion mass spectrometry. The results show that the VTE and subsequent Er3+ diffusion procedures resulted in totally ∼0.8 mol% Li2O content reduction. The Ti4+ profile follows a sum of two error functions in the width direction and a Gaussian function in the depth direction of waveguide. The Er3+ profile follows also a Gaussian function. At 1130 °C, the Ti4+ surface/depth diffusivity and surface concentration are 8.5 ± 1.3/1.98 ± 0.06 μm2/h and ∼7 mol%, respectively, and the Er3+ diffusivity and surface concentration are (12.8 ± 0.3) × 10−2 μm2/h and ∼0.6 mol%, respectively.
We demonstrate Er3+ diffusivity and solubility increases in off-congruent, Li-deficient LiNbO3 crystal. Li-poor vapor transport equilibration was used to reduce Li2O content in initial congruent crystals. Local Er3+ in-diffusion was then performed in a wet O2 atmosphere. Before and after the Er3+ diffusion procedure, surface Li2O content was evaluated from measured birefringence. The results show that the Er3+ diffusion procedure resulted in 0.3–0.5 mol% Li2O content loss at crystal surface. Secondary ion mass spectrometry was used to measure the Er3+ depth profiles, from which the diffusivity and solubility are determined. It is shown that the Er3+ diffusivity is nearly doubled and the solubility increases at least 0.6 mol% as the Li2O content decreases by 1.0 mol%. From the known Li2O content reduction, the solubility increase is also predicted and the results show that the predicted data are considerably smaller than the experimental results, suggesting that the Er3+ ions occupy also the Nb5+ site, besides the Li+ site.
We have measured at room temperature polarized visible and near-infrared and unpolarized mid-infrared (2.7 μm) emission spectra of Er3+ in LiNbO3 (LN) crystals grown from congruent melts doped with 0.0/0.5, 0.5/0.5, and 1.0/0.5 mol%/mol% In2O3/Er2O3. From the measured emission spectra, the emission and absorption cross section spectral distributions were analyzed based on McCumber theory and discussed in comparison with those spectra of only Er-doped LN bulk material and/or Ti: Er: LN waveguide structure and with the results from the unpolarized absorption measurements. For the 530 and 1530 nm transitions, the cross section value, polarization dependence, and spectral shape all change from the only Er-doped material to the In–Er-codoped crystal and show definite In2O3 doping level effect. The 559, 673, 996, and 1530 nm emission lifetimes were also measured and used to evaluate nonradiative multiphonon relaxation rate. The calculated radiative, measured lifetimes, and multiphonon relaxation rate also show In-codoping effects.
A rapid and sensitive real-time polymerase chain reaction (PCR) assay coupled with SYBR Green I chemistry was developed for the quantitative detection of Turbot reddish body iridovirus (TRBIV) isolated from farmed turbot (Scophthalmus maximus). A 152 bp DNA fragment from the TRBIV major capsid protein (MCP) gene was involved in the real-time PCR (RT-PCR) assay using the Roter Gene 3000 sequence detection system. The PCR mixture contained a fluorescent dye, SYBR Green I, which exhibited fluorescence enhancement when bound to double-stranded (ds) DNA. The enhancement of fluorescence was proportional to the initial concentration of the template DNA. The positive control plasmid, pUCm-T/TRBIV MCP, containing the target sequence, was quantified to make a standard curve for sample detection after serial tenfold dilution. Linear coefficient correlations between the cycle threshold (CT) value and logarithmic positive plasmid concentration were close to one (R2=0.9952) and the detection limit of the assay was 102 copies of positive plasmids. The quantitative detection of virus in different tissues from TRBIV-infected fish showed that the spleen and kidney contained the largest number of viral particles (5.23×106 and 2.18×106 viral genome copies/mg tissue, respectively), while no viral DNA was detected in the muscular tissue. The molecular epidemic investigation of TRBIV showed that many cultured turbots were infected and TRBIV has become epidemic in turbot farms located along the Shandong peninsula. The virus number varied from 1.27×102 to 2.33×106 viral genome copies/mg tissue in spleens of infected turbot. These results suggest that the RT-PCR assay reported here can be used as a rapid, sensitive and quantitative method for TRBIV.
A deficiency of dietary protein or amino acids has long been known to impair immune function and increase the susceptibility of animals and humans to infectious disease. However, only in the past 15 years have the underlying cellular and molecular mechanisms begun to unfold. Protein malnutrition reduces concentrations of most amino acids in plasma. Findings from recent studies indicate an important role for amino acids in immune responses by regulating: (1) the activation of T lymphocytes, B lymphocytes, natural killer cells and macrophages; (2) cellular redox state, gene expression and lymphocyte proliferation; and (3) the production of antibodies, cytokines and other cytotoxic substances. Increasing evidence shows that dietary supplementation of specific amino acids to animals and humans with malnutrition and infectious disease enhances the immune status, thereby reducing morbidity and mortality. Arginine, glutamine and cysteine precursors are the best prototypes. Because of a negative impact of imbalance and antagonism among amino acids on nutrient intake and utilisation, care should be exercised in developing effective strategies of enteral or parenteral provision for maximum health benefits. Such measures should be based on knowledge about the biochemistry and physiology of amino acids, their roles in immune responses, nutritional and pathological states of individuals and expected treatment outcomes. New knowledge about the metabolism of amino acids in leucocytes is critical for the development of effective means to prevent and treat immunodeficient diseases. These nutrients hold great promise in improving health and preventing infectious diseases in animals and humans.
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