115 results on '"Fan MZ"'
Search Results
2. Forecast Model of Transmission Line Sag Based on GA
- Author
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Zhang, F, primary, Fan, MZ, additional, Yu, XC, additional, Dong, X, additional, and Wang, WY, additional
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- 2022
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3. A transmission line fault rate correction method for meteorological risk sources
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Zhang, F, primary, Liu, XM, additional, Fan, MZ, additional, Dong, X, additional, and Yu, X, additional
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- 2022
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4. Abstract P6-05-05: Signaling Pathways Activated in Her 2 and ER Negative Breast Cancers
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Song, D, primary, Gao, L, additional, Cui, M, additional, Han, B, additional, Zhao, G, additional, Fu, T, additional, Li, P, additional, Ye, F, additional, Fan, MZ, additional, Pelletier, G, additional, and Zhang, DY., additional
- Published
- 2010
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5. Estimation of apparent L-amino acid diffusion in porcine jejunal enterocyte brush border membrane vesicles
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Fan, MZ, primary, Adeola, O, additional, and Asem, EK, additional
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- 2001
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6. Fractional protein synthesis rates are similar when measured by intraperitoneal or intravenous flooding doses of L-[ring-2H5]phenylalanine in combination with a rapid regimen of sampling in piglets.
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Bregendahl K, Yang X, Liu L, Yen JT, Rideout TC, Shen Y, Werchola G, Fan MZ, Bregendahl, Kristjan, Yang, Xiaojian, Liu, Lijuan, Yen, Jong-Tseng, Rideout, Todd C, Shen, Yingran, Werchola, George, and Fan, Ming Z
- Abstract
Fractional protein synthesis rates (FSR) are widely measured by the flooding dose technique via either an i.g. or an i.v. route. This study was conducted to compare differences in tracer incorporation and FSR in organs and tissues of fed piglets. The piglets were surgically implanted with catheters and randomly assigned to receive a flooding dose of Phe (1.5 mmol/kg body weight, 40 percent molar enrichment with [(2)H(5)]Phe) in saline administered via an i.p. or an i.v. route. [(2)H(5)]Phe free-pool enrichment in plasma increased logarithmically (P < 0.05) from 0 to 25% in the i.p. group, whereas it rose to a peak level within 3 min of the tracer injection and then decreased linearly (P < 0.05) in the i.v. group. Intracellular free-pool tracer enrichments in organs and tissues were within the range of the values measured for the plasma-free pool (25-27%), reaching the flooding status. Administration of the tracer via the i.p. and i.v. routes induced a logarithmical pattern (P < 0.05) of a surge in plasma cortisol concentrations within 30 min. Measurements of FSR in plasma, cardiac muscle, and skeletal muscles were lower (P < 0.05) in the i.p. than in the i.v. group due to the adverse effect of cortisol surge being more dramatic (P < 0.05) in the i.p. than in the i.v. group at 30 min of the post-tracer administration. We conclude that FSR may be measured by the flooding dose through an i.p. or an i.v. route and the i.p. route may underestimate FSR by the flooding dose for plasma, cardiac muscle, and skeletal muscles. This concern may be addressed by a fast regimen of sampling to be completed within 12-20 min after an i.p. route of tracer injection. [ABSTRACT FROM AUTHOR]
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- 2008
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7. Guar gum and similar soluble fibers in the regulation of cholesterol metabolism: current understandings and future research priorities.
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Rideout TC, Harding SV, Jones PJ, Fan MZ, Rideout, Todd C, Harding, Scott V, Jones, Peter Jh, and Fan, Ming Z
- Published
- 2008
8. Nutrient utilisation and intestinal fermentation are differentially affected by the consumption of resistant starch varieties and conventional fibres in pigs.
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Rideout TC, Liu Q, Wood P, and Fan MZ
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- 2008
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9. Staphylococcal enterotoxin B exposed to pregnant rats inhibits the hedgehog signaling pathway in thymic T lymphocytes of the offspring.
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Zhao JB, Fan MZ, Shi YX, Zhu YT, Gao SX, Li GL, Guan JC, and Zhou P
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- Animals, Female, Pregnancy, Rats, Zinc Finger Protein GLI1 metabolism, Zinc Finger Protein GLI1 genetics, Patched-1 Receptor metabolism, Patched-1 Receptor genetics, Smoothened Receptor metabolism, Smoothened Receptor genetics, Prenatal Exposure Delayed Effects immunology, Cell Differentiation drug effects, Rats, Sprague-Dawley, Male, Enterotoxins, Hedgehog Proteins metabolism, Hedgehog Proteins genetics, Signal Transduction, Thymus Gland metabolism, Thymus Gland immunology, T-Lymphocytes immunology, T-Lymphocytes metabolism
- Abstract
The Hedgehog (Hh) signaling pathway is involved in T cell differentiation and development and plays a major regulatory part in different stages of T cell development. A previous study by us suggested that prenatal exposure to staphylococcal enterotoxin B (SEB) changed the percentages of T cell subpopulation in the offspring thymus. However, it is unclear whether prenatal SEB exposure impacts the Hh signaling pathway in thymic T cells. In the present study, pregnant rats at gestational day 16 were intravenously injected once with 15 μg SEB, and the thymi of both neonatal and adult offspring rats were aseptically acquired to scrutinize the effects of SEB on the Hh signaling pathway. It firstly found that prenatal SEB exposure clearly caused the increased expression of Shh and Dhh ligands of the Hh signaling pathway in thymus tissue of both neonatal and adult offspring rats, but significantly decreased the expression levels of membrane receptors of Ptch1 and Smo, transcription factor Gli1, as well as target genes of CyclinD1, C-myc, and N-myc in Hh signaling pathway of thymic T cells. These data suggest that prenatal SEB exposure inhibits the Hh signaling pathway in thymic T lymphocytes of the neonatal offspring, and this effect can be maintained in adult offspring via the imprinting effect., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024. Published by Elsevier Ltd.)
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- 2024
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10. Modulation of Porcine Gut Microbiota and Microbiome: Hologenomic, Dietary, and Endogenous Factors.
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Fan MZ and Kim SW
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Global pig production contributes to about 35% of the world's meat production and consumption [...].
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- 2024
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11. Monomodular and multifunctional processive endocellulases: implications for swine nutrition and gut microbiome.
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Fan MZ, Cheng L, Wang M, Chen J, Fan W, Jashari F, and Wang W
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Poor efficiency of dietary fibre utilization not only limits global pork production profit margin but also adversely affects utilization of various dietary nutrients. Poor efficiency of dietary nutrient utilization further leads to excessive excretion of swine manure nutrients and results in environmental impacts of emission of major greenhouse gases (GHG), odor, nitrate leaching and surface-water eutrophication. Emission of the major GHG from intensive pork production contributes to global warming and deteriorates heat stress to pigs in tropical and sub-tropical swine production. Exogenous fibre enzymes of various microbial cellulases, hemicellulases and pectinases have been well studied and used in swine production as the non-nutritive gut modifier feed enzyme additives in the past over two decades. These research efforts have aimed to improve growth performance, nutrient utilization, intestinal fermentation as well as gut physiology, microbiome and health via complementing the porcine gut symbiotic microbial fibrolytic activities towards dietary fibre degradation. The widely reported exogenous fibre enzymes include the singular use of respective cellulases, hemicellulases and pectinases as well as their multienzyme cocktails. The currently applied exogenous fibre enzymes are largely limited by their inconsistent in vivo efficacy likely due to their less defined enzyme stability and limited biochemical property. More recently characterized monomodular, multifunctional and processive endoglucanases have the potential to be more efficaciously used as the next-generation designer fibre biocatalysts. These newly emerging multifunctional and processive endoglucanases have the potential to unleash dietary fibre sugar constituents as metabolic fuels and prebiotics, to optimize gut microbiome, to maintain gut permeability and to enhance performance in pigs under a challenged environment as well as to parallelly unlock biomass to manufacture biofuels and biomaterials., (© 2024. The Author(s).)
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- 2024
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12. Improving Flavonoid Accumulation of Bioreactor-Cultured Adventitious Roots in Oplopanax elatus Using Yeast Extract.
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Jin MY, Wang M, Wu XH, Fan MZ, Li HX, Guo YQ, Jiang J, Yin CR, and Lian ML
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Oplopanax elatus is an endangered medicinal plant, and adventitious root (AR) culture is an effective way to obtain its raw materials. Yeast extract (YE) is a lower-price elicitor and can efficiently promote metabolite synthesis. In this study, the bioreactor-cultured O. elatus ARs were treated with YE in a suspension culture system to investigate the elicitation effect of YE on flavonoid accumulation, serving for further industrial production. Among YE concentrations (25-250 mg/L), 100 mg/L YE was the most suitable for increasing the flavonoid accumulation. The ARs with various ages (35-, 40-, and 45-day-old) responded differently to YE stimulation, where the highest flavonoid accumulation was found when 35-day-old ARs were treated with 100 mg/L YE. After YE treatment, the flavonoid content increased, peaked at 4 days, and then decreased. By comparison, the flavonoid content and antioxidant activities in the YE group were obviously higher than those in the control. Subsequently, the flavonoids of ARs were extracted by flash extraction, where the optimized extraction process was: 63% ethanol, 69 s of extraction time, and a 57 mL/g liquid-material ratio. The findings provide a reference for the further industrial production of flavonoid-enriched O. elatus ARs, and the cultured ARs have potential application for the future production of products.
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- 2023
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13. Deglycosylation Differentially Regulates Weaned Porcine Gut Alkaline Phosphatase Isoform Functionality along the Longitudinal Axis.
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Yin X, Wang W, Seah SYK, Mine Y, and Fan MZ
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Gut alkaline phosphatases (AP) dephosphorylate the lipid moiety of endotoxin and other pathogen-associated-molecular patterns members, thus maintaining gut eubiosis and preventing metabolic endotoxemia. Early weaned pigs experience gut dysbiosis, enteric diseases and growth retardation in association with decreased intestinal AP functionality. However, the role of glycosylation in modulation of the weaned porcine gut AP functionality is unclear. Herein three different research approaches were taken to investigate how deglycosylation affected weaned porcine gut AP activity kinetics. In the first approach, weaned porcine jejunal AP isoform (IAP) was fractionated by the fast protein-liquid chromatography and purified IAP fractions were kinetically characterized to be the higher-affinity and lower-capacity glycosylated mature IAP ( p < 0.05) in comparison with the lower-affinity and higher-capacity non-glycosylated pre-mature IAP. The second approach enzyme activity kinetic analyses showed that N -deglycosylation of AP by the peptide N -glycosidase-F enzyme reduced ( p < 0.05) the IAP maximal activity in the jejunum and ileum and decreased AP affinity ( p < 0.05) in the large intestine. In the third approach, the porcine IAP isoform-X1 (IAPX1) gene was overexpressed in the prokaryotic ClearColiBL21 (DE3) cell and the recombinant porcine IAPX1 was associated with reduced ( p < 0.05) enzyme affinity and maximal enzyme activity. Therefore, levels of glycosylation can modulate plasticity of weaned porcine gut AP functionality towards maintaining gut microbiome and the whole-body physiological status.
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- 2023
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14. Characterization of in vitro stability for two processive endoglucanases as exogenous fibre biocatalysts in pig nutrition.
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Cheng L, Wang W, and Fan MZ
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- Animals, Catalytic Domain, Cellulose metabolism, Dietary Fiber, Swine, Cellulase metabolism, Cellulases metabolism
- Abstract
Development of highly efficacious exogenous fibre degradation enzymes can enhance efficiency of dietary fibre utilization and sustainability of global pork production. The objectives of this study were to investigate in vitro stability for two processive endoglucanases, referred to as GH5-tCel5A1 and GH5-p4818Cel5_2A that were overexpressed in CLEARCOLIBL21(DE3). Three-dimensional models predicted presence of Cys residues on the catalytic site surfaces of GH5-tCel5A1 and GH5-p4818Cel5_2A; and time course experimental results shown that both cellulases were susceptible to auto-oxidation by airborne O
2 and were unstable. Furthermore, we examined these endoglucanases' stability under the mimicked in vitro porcine gastric and the small intestinal pH and proteases' conditions. Eadie-Hofstee inhibition kinetic analyses showed that GH5-tCel5A1 and GH5-p4818Cel5_2A respectively lost 18 and 68% of their initial activities after 2-h incubations under the gastric conditions and then lost more than 90% of their initial activities after 2-3 h of incubations under the small intestinal conditions. Therefore, further enzyme protein engineering to improve resistance and alternatively post-fermentation enzyme processing such as coating to bypass the gastric-small intestinal environment will be required to enable these two processive endoglucanases as efficacious exogenous fibre enzymes in pig nutrition application., (© 2022. The Author(s).)- Published
- 2022
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15. [Effects of non-muscle myosin Ⅱ silenced bone marrow-derived mesenchymal stem cells transplantation on lung extracellular matrix in rats after endotoxin/lipopolysaccharide-induced acute lung injury].
- Author
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Yin X, Zhou WF, Hou WJ, Fan MZ, Wu GS, Liu XB, Ma QM, Wang YS, and Zhu F
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- Animals, Bone Marrow, Collagen metabolism, Endotoxins, Extracellular Matrix, Lipopolysaccharides adverse effects, Lung, Male, Malondialdehyde metabolism, Matrix Metalloproteinase 2 metabolism, Matrix Metalloproteinase 9 metabolism, Myosin Type II metabolism, Rats, Rats, Sprague-Dawley, Saline Solution metabolism, Superoxide Dismutase metabolism, Acute Lung Injury chemically induced, Acute Lung Injury metabolism, Acute Lung Injury therapy, Mesenchymal Stem Cells metabolism, Pulmonary Fibrosis
- Abstract
Objective: To investigate the effects of non-muscle myosin Ⅱ ( NMⅡ ) gene silenced bone marrow-derived mesenchymal stem cells (BMMSCs) on pulmonary extracellular matrix (ECM) and fibrosis in rats with acute lung injury (ALI) induced by endotoxin/lipopolysaccharide (LPS). Methods: The experimental research methods were adopted. Cells from femur and tibial bone marrow cavity of four one-week-old male Sprague-Dawley rats were identified as BMMSCs by flow cytometry, and the third passage of BMMSCs were used in the following experiments. The cells were divided into NMⅡ silenced group transfected with pHBLV-U6-ZsGreen-Puro plasmid containing small interference RNA sequence of NMⅡ gene, vector group transfected with empty plasmid, and blank control group without any treatment, and the protein expression of NMⅡ at 72 h after intervention was detected by Western blotting ( n =3). The morphology of cells was observed by an inverted phase contrast microscope and cells labeled with chloromethylbenzoine (CM-DiⅠ) in vitro were observed by an inverted fluorescence microscope. Twenty 4-week-old male Sprague-Dawley rats were divided into blank control group, ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group according to the random number table, with 5 rats in each group. Rats in blank control group were not treated, and rats in the other 3 groups were given LPS to induce ALI. Immediately after modeling, rats in ALI alone group were injected with 1 mL normal saline via tail vein, rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were injected with 1×10
7 /mL BMMSCs and NMⅡ gene silenced BMMSCs of 1 mL labelled with CM-DiⅠ via tail vein, and rats in blank control group were injected with 1 mL normal saline via tail vein at the same time point, respectively. At 24 h after intervention, the lung tissue was collected to observe intrapulmonary homing of the BMMSCs by an inverted fluorescence microscope. Lung tissue was collected at 24 h, in 1 week, and in 2 weeks after intervention to observe pulmonary inflammation by hematoxylin eosin staining and to observe pulmonary fibrosis by Masson staining, and the pulmonary fibrosis in 2 weeks after intervention was scored by modified Ashcroft score ( n =5). The content of α-smooth muscle actin (α-SMA), matrix metalloproteinase 2 (MMP-2), and MMP-9 was detected by immunohistochemistry in 2 weeks after intervention ( n =3), the activity of superoxide dismutase (SOD), malondialdehyde, myeloperoxidase (MPO) was detected by enzyme-linked immunosorbent assay at 24 h after intervention ( n =3), and the protein expressions of CD11b and epidermal growth factor like module containing mucin like hormone receptor 1 (EMR1) in 1 week after intervention were detected by immunofluorescence staining ( n =3). Data were statistically analyzed with one-way analysis of variance, Bonferroni method, and Kruskal-Wallis H test. Results: At 72 h after intervention, the NMⅡprotein expression of cells in NMⅡ silenced group was significantly lower than those in blank control group and vector group (with P values <0.01). BMMSCs were in long spindle shape and grew in cluster shaped like vortexes, which were labelled with CM-DiⅠ successfully in vitro. At 24 h after intervention, cell homing in lung of rats in ALI+NMⅡ silenced BMMSC group was more pronounced than that in ALI+BMMSC group, while no CM-DiⅠ-labelled BMMSCs were observed in lung of rats in blank control group and ALI alone group. There was no obvious inflammatory cell infiltration in lung tissue of rats in blank control group at all time points, while inflammatory cell infiltration in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly less than that in ALI alone group at 24 h after intervention, and alveolar wall turned to be thinner and a small amount of congestion in local lung tissue appeared in rats of the two groups in 1 week and 2 weeks after intervention. In 1 week and 2 weeks after intervention, collagen fiber deposition in lung tissue of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group was significantly aggravated compared with that in blank control group, while collagen fiber deposition in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly improved compared with that in ALI alone group. In 2 weeks after intervention, modified Ashcroft scores for pulmonary fibrosis of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group were 2.36±0.22, 1.62±0.16, 1.06±0.26, respectively, significantly higher than 0.30±0.21 in blank control group ( P <0.01). Modified Ashcroft scores for pulmonary fibrosis of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly lower than that in ALI alone group ( P <0.01), and modified Ashcroft score for pulmonary fibrosis of rats in ALI+NMⅡ silenced BMMSC group was significantly lower than that in ALI+BMMSC group ( P <0.01). In 2 weeks after intervention, the content of α-SMA in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly decreased compared with that in ALI alone group ( P <0.05 or P <0.01). The content of MMP-2 in lung tissue of rats in the 4 groups was similar ( P >0.05). The content of MMP-9 in lung tissue of rats in ALI alone group was significantly increased compared with that in blank control group ( P <0.01), and the content of MMP-9 in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI alone group ( P <0.01). At 24 h after intervention, the activity of malondialdehyde, SOD, and MPO in lung tissue of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group were significantly increased compared with that in blank control group ( P <0.01), the activity of malondialdehyde in lung tissue of rats in ALI+NMⅡ silenced BMMSC group and the activity of SOD in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly increased compared with that in ALI alone group ( P <0.05 or P <0.01), and the activity of SOD in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI+BMMSC group ( P <0.01). The activity of MPO in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI alone group ( P <0.01), and the activity of MPO in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI+BMMSC group ( P <0.01). In 1 week after intervention, the protein expression of CD11b in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly increased compared with those in the other three groups ( P <0.05 or P <0.01), while the protein expressions of EMR1 in lung tissue of rats in the four groups were similar ( P >0.05). Conclusions: Transplantation of NMⅡ gene silenced BMMSCs can significantly improve the activity of ECM components in the lung tissue in LPS-induced ALI rats, remodel its integrity, and enhance its antioxidant capacity, and alleviate lung injury and pulmonary fibrosis.- Published
- 2022
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16. Hepatoprotective Effect of Oplopanax elatus Nakai Adventitious Roots Extract by Regulating CYP450 and PPAR Signaling Pathway.
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Jiang XL, Luo PY, Zhou YY, Luo ZH, Hao YJ, Fan MZ, Wu XH, Gao H, Bi HC, Zhao ZB, Lian ML, and Lian ZX
- Abstract
O. elatus Nakai is a traditional medicine that has been confirmed to exert effective antioxidant and anti-inflammatory functions, and is used for the treatment of different disorders. However, its potential beneficial effects on drug induced hepatotoxicity and relevant molecular mechanisms remain unclear. This study investigated the protective effect and further elucidated the mechanisms of action of O. elatus on liver protection. O. elatus chlorogenic acids-enriched fraction (OEB), which included chlorogenic acid and isochlorogenic acid A, were identified by HPLC-MS/MS. OEB was administrated orally daily for seven consecutive days, followed by a single intraperitoneal injection of an overdose of APAP after the final OEB administration. The effects of OEB on immune cells in mice liver were analyzed using flow cytometry. APAP metabolite content in serum was detected using HPLC-MS/MS in order to investigate whether OEB affects CYP450 activities. The intestinal content samples were processed for 16 s microbiota sequencing. Results demonstrated that OEB decreased alanine aminotransferase, aspartate aminotransferase contents, affected the metabolism of APAP, and decreased the concentrates of APAP, APAP-CYS and APAP-NAC by inhibiting CYP2E1 and CYP3A11 activity. Furthermore, OEB pretreatment regulated lipid metabolism by affecting the peroxisome proliferator-activated receptors (PPAR) signaling pathway in mice and also increased the abundance of Akkermansia and Parabacteroides . This study indicated that OEB is a potential drug candidate for treating hepatotoxicity because of its ability to affect drug metabolism and regulate lipid metabolism., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jiang, Luo, Zhou, Luo, Hao, Fan, Wu, Gao, Bi, Zhao, Lian and Lian.)
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- 2022
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17. Co-cultured adventitious roots of Echinacea pallida and Echinacea purpurea inhibit lipopolysaccharide-induced inflammation via MAPK pathway in mouse peritoneal macrophages.
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Fan MZ, Wu XH, Li XF, Piao XC, Jiang J, and Lian ML
- Abstract
Objective: In order to elucidate the biological activity of the co-cultured adventitious roots (ARs) of Echinacea pallida and Echinacea purpurea and provide theoretical basis for its application, and the anti-inflammatory activities and potential mechanisms of co-cultured ARs were studied., Methods: The experimental materials were obtained by bioreactor co-culture technology and used in the activity research. In this study, mouse macrophages induced by lipopolysaccharide (LPS) were used as in vitro model. Different concentrations of AR extract (50-400 g/mL) were used to treat cells. The expression of pro-inflammatory cytokines was determined using enzyme linked immunosorbent assay. The inducible nitric oxide synthase and cyclooxygenase-2 expression, mitogen-activated protein kinase (MAPK) phosphorylation, and the inhibitor of nuclear factor-kappa B-α levels were determined by the Western blot analysis., Results: In the co-cultured ARs, total flavonoids and total caffeic acid were determined, and the contents of both bioactive compounds were significantly higher than those ARs from the single-species culture. Compared with the control group, the large amount of pro-inflammatory mediators was released after LPS stimulation. However, in the extract groups with different concentrations (25, 50, and 100 g/mL), the production of these pro-inflammatory mediators was inhibited in a dose-dependent manner. Furthermore, the levels of phosphorylation of MAPK proteins, including p-p38, p-c-Jun N-terminal kinase, and p-extracellular regulated protein kinases were significantly ( P < 0.05) decreased in the extract groups, revealing that the AR extract probably involved in regulating the MAPK signaling pathway., Conclusion: Collectively, our findings suggested that the co-cultured ARs of E. pallida and E. purpurea can inhibit production of pro-inflammatory mediators in mouse peritoneal macrophages and possess the anti-inflammatory effect by regulating MAPK signaling pathways., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 Tianjin Press of Chinese Herbal Medicines. Published by ELSEVIER B.V.)
- Published
- 2021
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18. Cost-Effective Monolithic Hierarchical Carbon Cryogels with Nitrogen Doping and High-Performance Mechanical Properties for CO 2 Capture.
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Li ZL, Zhou YL, Yan W, Luo L, Su ZZ, Fan MZ, Wang SR, and Zhao WG
- Abstract
Cost-effective nitrogen-doped monolithic hierarchical carbon cryogels with excellent mechanical properties and carbon dioxide (CO
2 ) adsorption performance were prepared from phenol, melamine, and formaldehyde (PMF) by the sol-gel, freeze-drying, and then, pyrolysis processes under an inert atmosphere. The morphology, mechanical properties, pore structure, and chemical characteristics of these cryogels were investigated. The results showed that the dilution ratio played a crucial role in the preparation of nitrogen-doped PMF carbon cryogels with controlled structures. The prepared carbon cryogels were a kind of monolithic materials composed of a hierarchical pore structure and had high compression properties (0.67 and 9.4 MPa for strength and modulus), porosity (97.6%), surface area (1406 m2 /g), and heteroatom nitrogen content (0.98-2.09%). CO2 adsorption capacities up to 5.75 mmol/g at 0 °C and 4.50 mmol/g at 25 °C under 1 bar were obtained, which is at a high level among N-doped carbon materials and far better than resorcinol-based carbon gels reported. These superior CO2 adsorption capacities, high isosteric adsorption heat ( Qst ), and good CO2 /N2 adsorption selectivity were ascribed to the synergistic effect of high surface area, appropriate pore size, and also heteroatom doping.- Published
- 2020
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19. Effect of milk protein composition and amount of β-casein on growth performance, gut hormones, and inflammatory cytokines in an in vivo piglet model.
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Rafiee-Tari N, Fan MZ, Archbold T, Arranz E, and Corredig M
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- Animals, Caseins metabolism, Diet veterinary, Energy Metabolism, Female, Interleukin-10 metabolism, Male, Milk metabolism, Milk Proteins chemistry, Milk Proteins metabolism, Random Allocation, Swine, Whey Proteins analysis, Whey Proteins metabolism, Whey Proteins pharmacology, Animal Feed, Caseins pharmacology, Cytokines metabolism, Milk Proteins pharmacology
- Abstract
The objective of this work was to better understand the effect of differences in milk protein composition, and specifically, a change in β-casein to total casein in a milk-based matrix, on growth performance and metabolic and inflammatory responses using a piglet model. Three formulas were optimized for piglets, with similar metabolizable energy, total protein content, and other essential nutrients. Only the protein type and ratio varied between the treatments: the protein fraction of the control diet contained only whey proteins, whereas 2 other matrices contained a whey protein to casein ratio of 60:40, and differed in the amount of β-casein (12.5 and 17.1% of total protein). Piglets fed formula containing whey proteins and caseins, regardless of the concentration of β-casein, showed a significantly higher average daily gain, average daily feed intake, and feed efficiency compared with piglets consuming the formula with only whey protein. Consumption of the formula containing only whey protein showed higher levels of plasma glucagon-like peptide-1 and ghrelin compared with the consumption of formula containing casein and whey protein. A positive correlation was observed between postprandial time and glucagon-like peptide-1 response. The intestinal pro-inflammatory cytokine tumor necrosis factor α increased significantly in piglets fed the whey protein/casein diet compared with those fed whey protein formula. All formula-fed piglets showed a lower level of IL-6 cytokine compared with the ad libitum sow-fed piglets, regardless of composition. No significant differences in the anti-inflammatory IL-10 concentration were observed between treatment groups. Milk protein composition contributed to the regulation of piglets' metabolic and physiological responses, with whey protein/casein formula promoting growth performance and a different immune regulatory balance compared with a formula containing only whey protein. Results indicated no differences between treatments containing different levels of β-casein., (Copyright © 2019 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)
- Published
- 2019
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20. A processive endoglucanase with multi-substrate specificity is characterized from porcine gut microbiota.
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Wang W, Archbold T, Lam JS, Kimber MS, and Fan MZ
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- Animals, Bacteria enzymology, Bacterial Proteins chemistry, Bacterial Proteins genetics, Bacterial Proteins metabolism, Catalytic Domain, Cellobiose metabolism, Cellulase chemistry, Cellulase genetics, Gastrointestinal Microbiome, Models, Molecular, Protein Conformation, Substrate Specificity, Swine, Trioses metabolism, Bacteria isolation & purification, Cellulase metabolism, Cellulose metabolism, Polysaccharides metabolism
- Abstract
Cellulases play important roles in the dietary fibre digestion in pigs, and have multiple industrial applications. The porcine intestinal microbiota display a unique feature in rapid cellulose digestion. Herein, we have expressed a cellulase gene, p4818Cel5_2A, which singly encoded a catalytic domain belonging to glycoside hydrolase family 5 subfamily 2, and was previously identified from a metagenomic expression library constructed from porcine gut microbiome after feeding grower pigs with a cellulose-supplemented diet. The activity of purified p4818Cel5_2A was maximal at pH 6.0 and 50 °C and displayed resistance to trypsin digestion. This enzyme exhibited activities towards a wide variety of plant polysaccharides, including cellulosic substrates of avicel and solka-Floc
® , and the hemicelluloses of β-(1 → 4)/(1 → 3)-glucans, xyloglucan, glucomannan and galactomannan. Viscosity, reducing sugar distribution and hydrolysis product analyses further revealed that this enzyme was a processive endo-β-(1 → 4)-glucanase capable of hydrolyzing cellulose into cellobiose and cellotriose as the primary end products. These catalytic features of p4818Cel5_2A were further explored in the context of a three-dimensional homology model. Altogether, results of this study report a microbial processive endoglucanase identified from the porcine gut microbiome, and it may be tailored as an efficient biocatalyst candidate for potential industrial applications.- Published
- 2019
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21. Apparent and true digestibility of macro and micro nutrients in adult maintenance dog foods containing either a majority of animal or vegetable proteins1.
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Cargo-Froom CL, Fan MZ, Pfeuti G, Pendlebury C, and Shoveller AK
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- Animal Feed analysis, Animal Nutritional Physiological Phenomena, Animals, Diet veterinary, Dietary Proteins analysis, Feces chemistry, Female, Gastrointestinal Tract physiology, Male, Nutrients, Phosphorus, Dietary, Random Allocation, Vegetables, Animal Feed standards, Dietary Proteins classification, Digestion, Dogs physiology, Minerals metabolism
- Abstract
There is dearth of knowledge with regards to mineral digestibility of ingredients in canines, and current knowledge is focused on the digestibility of supplemented minerals, not on intrinsic mineral digestibility of ingredients. The objectives of the present study were to determine the apparent and true digestibility (TD) of macronutrients and micronutrients, and the total tract gastrointestinal endogenous nutrient outputs in canines fed either animal- or vegetable-based adult maintenance diets. Eight purpose bred Beagles (two intact males, six spayed females) of similar age (2.12 ± 0.35 yr, mean ± SD) and weight (9.92 ± 0.73 kg, mean ± SD) were pair housed in kennels but fed individually based on individual maintenance energy requirements. Two basal diets (animal and vegetable protein based) were formulated to meet nutritional requirements of adult canines. Two additional trial diets were created, using the basal diets, by diluting diets by 50% with anhydrous α-d-glucose to attempt to quantify endogenous mineral losses and enable calculation of TD. All diets contained titanium dioxide at 0.3% for calculations of nutrient digestibility. Dogs were provided with deionized water as their only source of water throughout the trial. Dogs in a specific kennel were randomly assigned to an experimental diet for 10 d (experimental period), and fecal samples were collected the last 4 d of each period. All dogs were fed all experimental diets in random order based on a 4 × 4 replicated Latin square design. Dogs fed intact diets had a higher apparent mineral digestibility compared to dogs fed diluted diets (P < 0.05). Apparent phosphorus digestibility was higher for dogs fed the diet 2 compared with the diet 1 (P = 0.01) and the diluted diets (P < 0.001). There was a trend towards a greater TD of Cu for dogs fed the diet 2 compared with the diet 1 (P = 0.08). P, Mg, Zn, and Mn true digestibilities were higher for dogs fed the diet 2 compared with the diet 1 (P < 0.05, P = 0.01, P = 0.02, P = 0.009, respectively). These results suggest that apparent and TD do not result in similar values. Further research should be conducted on TD in canines only if a better model is developed., (© The Author(s) 2019. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2019
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22. Transcriptomic analyses of tributyltin-induced sexual dimorphisms in rare minnow (Gobiocypris rarus) brains.
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Zhang JL, Liu M, Zhang CN, Li EC, Fan MZ, and Huang MX
- Subjects
- Animals, Brain drug effects, Brain metabolism, Circadian Rhythm drug effects, Cyprinidae metabolism, Female, Gene Expression Profiling, Light Signal Transduction drug effects, Male, Sequence Analysis, RNA, Cyprinidae genetics, Sex Characteristics, Transcriptome drug effects, Trialkyltin Compounds toxicity
- Abstract
The brain of fish displays sexual dimorphisms and exhibits remarkable sexual plasticity throughout their life span. Although reproductive toxicity of tributyltin (TBT) in fish is well documented in fish, it remains unknown whether TBT interrupts sexual dimorphisms of fish brains. In this work, brain transcriptomic profiles of rare minnow (Gobiocypris rarus) was characterized and sex-biased genes were identified using RNA sequencing. Functional annotation and enrichment analysis were performed to reveal differences of gene products and pathways between the brains of male and female fish. Furthermore, transcriptomic responses of male and female brains to TBT at 10 ng/L were also investigated to understand effects of TBT on brain sexual dimorphisms. Only 345 male-biased and 273 female-biased genes were found in the brains. However, significant female-biased pathways of circadian rhythm and phototransduction were identified in the brains by enrichment analysis. Interestingly, following TBT exposure in the female fish, the circadian rhythm pathway was significantly disrupted based on enrichment analysis, while in the male fish, the phototransduction pathway was significantly disrupted. In the female fish, expression of genes (Per, Cry, Rev-Erb α, Ror, Dec and CK1δ/ε) in the circadian rhythm pathway was down-regulated after TBT exposure; while in the male fish, expression of genes (Rec, GNAT1_2, GNGT1, Rh/opsin, PDE and Arr) in the phototransduction pathway was up-regulated after TBT exposure. Overall, our results not only provide key data on the molecular basis of brain sexual dimorphisms in fish, but also offer valuable resources for investigating molecular mechanisms by which environmental chemicals might influence brain sexual plasticity., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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23. Cornelis (Kees) Franciscus Maria de Lange (1961-2016): a brief biography.
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Patience JF and Fan MZ
- Published
- 2018
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24. Effect of milk protein composition of a model infant formula on the physicochemical properties of in vivo gastric digestates.
- Author
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Tari NR, Fan MZ, Archbold T, Kristo E, Guri A, Arranz E, and Corredig M
- Subjects
- Animals, Animals, Newborn, Caseins pharmacology, Diet, Female, Food, Formulated, Hydrolysis, Swine, Viscosity, Whey Proteins pharmacology, Digestion, Gastric Mucosa metabolism, Infant Formula chemistry, Milk chemistry, Milk Proteins chemistry
- Abstract
We investigated the effect of protein composition and, in particular, the presence of whey proteins or β-casein on the digestion behavior of a model infant formula using an in vivo piglet model. Three isocaloric diets optimized for piglets were prepared with the same concentrations of protein. For protein source, 1 diet contained only whey proteins and 2 contained a casein:whey protein ratio of 40:60 but differed in the amount of β-casein. To obtain the desired protein compositions, skim milk was microfiltered at 7 or 22°C, and retentates and permeates were combined with whey protein isolate. The diets were optimized to the nutritional needs of the piglets and fed to 24 newborn piglets for 18 d. Eight piglets were also fed ad libitum with sow milk and considered only as reference (not included in the statistical analysis). The study was carried out in 2 blocks, killing the animals 60 and 120 min after the last meal. All gastric contents, regardless of diet, showed a wide range of pH. Postprandial time did not affect the pH or physical properties of the gastric digesta. The digesta from whey protein-casein formulas showed significantly higher viscosity, a higher storage modulus, and a denser microstructure than digesta obtained from piglets fed whey protein formula. The β-casein:total casein ratio at the level used in this study did not significantly affect the physical and chemical properties of the stomach digestate. Although caseins showed extensive gastric hydrolysis, whey proteins remained largely intact at both postprandial times. The results indicate that the presence of different concentrations of milk proteins can be critical to the digestion properties of the food matrix and may affect the nutritional properties of the components., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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25. Transcriptome analyses of sex differential gene expression in brains of rare minnow ( Gobiocypris rarus ) and effects of tributyltin exposure.
- Author
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Zhang JL, Zhang CN, Liu M, Fan MZ, and Huang MX
- Abstract
RNA-sequencing was used to identify sex-biased gene expression in brains of rare minnow ( Gobiocypris rarus ) by comparing transcriptomic profiles between females and males. Furthermore, transcriptomic responses to 10 ng/L tributyltin (TBT) in both male and female brains were also investigated to understand whether TBT affects the identified sex-biased genes. Differentially expressed genes (DEGs) were identified using the IDEG6 web tool. In this article, we presented male- and female-biased DEGs, and up-regulated and down-regulated DEGs after TBT exposure. The raw reads data supporting the present analyses has been deposited in NCBI Sequence Read Archive (SRA, http://www.ncbi.nlm.nih.gov/Traces/sra) with accession number PRJNA376634. The data presented in this article are related to the research article entitled "Transcriptomic analyses of sexual dimorphism of rare minnow ( G. rarus ) brains and effects of tributyltin exposure" (doi: 10.1016/j.ecoenv.2018.02.049).
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- 2018
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26. Interleukin-10 is differentially expressed in the small intestine and the colon experiencing chronic inflammation and ulcerative colitis induced by dextran sodium sulfate in young pigs.
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Lackeyram D, Young D, Kim CJ, Yang C, Archbold TL, Mine Y, and Fan MZ
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- Animals, Animals, Newborn, Colitis, Ulcerative pathology, Colon drug effects, Colon pathology, Gene Expression, Inflammation chemically induced, Inflammation metabolism, Inflammation pathology, Interleukin-10 genetics, Intestine, Small drug effects, Intestine, Small pathology, Swine, Colitis, Ulcerative chemically induced, Colitis, Ulcerative metabolism, Colon metabolism, Dextran Sulfate toxicity, Interleukin-10 biosynthesis, Intestine, Small metabolism
- Abstract
Intestinal inflammation induced with dextran sodium sulfate (DSS) is used to study acute or chronic ulcerative colitis in animal models. Decreased gut tissue anti-inflammatory cytokine IL-10 concentration and mRNA abundance are associated with the development of chronic bowel inflammation. Twelve piglets of 3 days old were fitted with an intragastric catheter and randomly allocated into control and DSS groups by administrating either sterile saline or 1.25 g of DSS/kg body weight (BW) in saline per day, respectively, for 10 days. Growth rate and food conversion efficiency were reduced (p<0.05) in the DSS piglets compared with the control group. Quantitative histopathological grading of inflammation in the jejunum and colon collectively showed that the DSS treatment resulted in 12 fold greater (p<0.05) inflammation severity scoring in the colon than in the jejunum, indicative of chronic ulcerative colitis in the colon. Upper gut permeability endpoint was 27.4 fold higher (p<0.05) in the DSS group compared with the control group. The DSS group had higher concentrations and mRNA abundances (p<0.05) of TNF-alpha and IL-6 in the jejunal and colonic tissues compared with the control group. Colonic concentration and mRNA abundance of IL-10 were reduced (p<0.05), however, jejunal IL-10 mRNA abundance was increased (p<0.05) in the DSS group compared with the control group. In conclusion, administration of DSS at 1.25 g/kg BW for 10 days respectively induced acute inflammation in the jejunum and chronic inflammation and ulcerative colitis in the colon with substantially decreased colonic concentration and mRNA abundance of IL-10 in the young pigs, mimicking the IL-10 expression pattern in humans Associated with chronic bowel inflammation.
- Published
- 2017
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27. Expression of apical Na(+)-L-glutamine co-transport activity, B(0)-system neutral amino acid co-transporter (B(0)AT1) and angiotensin-converting enzyme 2 along the jejunal crypt-villus axis in young pigs fed a liquid formula.
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Yang C, Yang X, Lackeyram D, Rideout TC, Wang Z, Stoll B, Yin Y, Burrin DG, and Fan MZ
- Subjects
- Angiotensin-Converting Enzyme 2, Animals, Female, Male, Swine, Amino Acid Transport Systems, Basic biosynthesis, Amino Acid Transport Systems, Neutral biosynthesis, Animal Feed, Gene Expression Regulation, Intestinal Mucosa metabolism, Jejunum metabolism, Peptidyl-Dipeptidase A biosynthesis
- Abstract
Gut apical amino acid (AA) transport activity is high at birth and during suckling, thus being essential to maintain luminal nutrient-dependent mucosal growth through providing AA as essential metabolic fuel, substrates and nutrient stimuli for cellular growth. Because system-B(0) Na(+)-neutral AA co-transporter (B(0)AT1, encoded by the SLC6A19 gene) plays a dominant role for apical uptake of large neutral AA including L-Gln, we hypothesized that high apical Na(+)-Gln co-transport activity, and B(0)AT1 (SLC6A19) in co-expression with angiotensin-converting enzyme 2 (ACE2) were expressed along the entire small intestinal crypt-villus axis in young animals via unique control mechanisms. Kinetics of Na(+)-Gln co-transport activity in the apical membrane vesicles, prepared from epithelial cells sequentially isolated along the jejunal crypt-villus axis from liquid formula-fed young pigs, were measured with the membrane potential being clamped to zero using thiocyanate. Apical maximal Na(+)-Gln co-transport activity was much higher (p < 0.05) in the upper villus cells than in the middle villus (by 29 %) and the crypt (by 30 %) cells, whereas Na(+)-Gln co-transport affinity was lower (p < 0.05) in the upper villus cells than in the middle villus and the crypt cells. The B(0)AT1 (SLC6A19) mRNA abundance was lower (p < 0.05) in the crypt (by 40-47 %) than in the villus cells. There were no significant differences in B(0)AT1 and ACE2 protein abundances on the apical membrane among the upper villus, the middle villus and the crypt cells. Our study suggests that piglet fast growth is associated with very high intestinal apical Na(+)-neutral AA uptake activities via abundantly co-expressing B(0)AT1 and ACE2 proteins in the apical membrane and by transcribing the B(0)AT1 (SLC6A19) gene in the epithelia along the entire crypt-villus axis.
- Published
- 2016
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28. Novel and disruptive biological strategies for resolving gut health challenges in monogastric food animal production.
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Fan MZ and Archbold T
- Abstract
Use of feed antibiotics as growth promoters for control of pathogens associated with monogastric food animal morbidity and mortality has contributed to the development of antimicrobial resistance, which has now become a threat to public health on a global scale. Presently, a number of alternative feed additives have been developed and are divided into two major categories, including 1) the ones that are supposed to directly and indirectly control pathogenic bacterial proliferation; and 2) the other ones that are intended to up-regulate host gut mucosal trophic growth, whole body growth performance and active immunity. A thorough review of literature reports reveal that efficacy responses of current alternative feed additives in replacing feed antibiotics to improve performances and gut health are generally inconsistent dependent upon experimental conditions. Current alternative feed additives typically have no direct detoxification effects on endotoxin lipopolysaccharides (LPS) and this is likely the major reason that their effects are limited. It is now understood that pathogenic bacteria mediate their negative effects largely through LPS interactions with toll-like receptor 4, causing immune responses and infectious diseases. Therefore, disruptive biological strategies and a novel and new generation of feed additives need to be developed to replace feed antibiotic growth promoters and to directly and effectively detoxify the endotoxin LPS and improve gut health and performance in monogastric food animals.
- Published
- 2015
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29. [Effects of different long-term fertilization on the activities of enzymes related to carbon, nitrogen, and phosphorus cycles in a red soil].
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Fan MZ, Yin C, Fan FL, Song AL, Wang BR, Li DC, and Liang YC
- Subjects
- Animals, Carbon analysis, Manure, Nitrates analysis, Nitrogen analysis, Phosphorus analysis, Potassium analysis, Swine, Carbon Cycle, Enzymes analysis, Fertilizers, Nitrogen Cycle, Soil chemistry, Soil Microbiology
- Abstract
Using a microplate fluorimetric assay method, five fertilization treatments, i.e. no-fertilizer control (CK) , sole application of nitrogen (N), balanced application of nitrogen, phosphorus, and potassium fertilizer (NPK), application of pig manure (M), and combination of pig manure with balanced chemical fertilizer (MNPK) were selected to investigate the effects of different long-term fertilization regimes on the activity of five enzymes (β-1, 4-glucosidase, βG; cellobiohydrolase, CBH; β-1, 4-xylosidase, βX; β-1, 4-N-acetylglucosaminidase, NAG; acid phosphatase, AP) in a red soil sampled from Qiyang, Hunnan Province. The results showed that compared with CK treatment, N treatment had no impact on βG, βX, CBH, and NAG activities but reduced AP activity, while NPK, M and MNPK treatments increased the activities of all the five enzymes. Correlation analysis indicated that all the five enzyme activities were positively correlated with the content of nitrate (r=0.465-0.733) , the content of available phosphorus (r=0.612-0.947) , soil respiration (r=0.781-0.949) and crop yield (r=0.735-0.960), while βG, CBH and AP were positively correlated with pH (r= 0.707-0.809), only AP was significantly correlated with dissolvable organic carbon (r = -0.480). These results suggested that the activities of the measured enzymes could be used as indicators of red soil fertility under different fertilization regimes, but the five enzymes tested provided limited information on the degree of acidification induced by application of mineral nitrogen.
- Published
- 2015
30. Comparative carcass and tissue nutrient composition of transgenic Yorkshire pigs expressing phytase in the saliva and conventional Yorkshire pigs.
- Author
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Forsberg CW, Meidinger RG, Ajakaiye A, Murray D, Fan MZ, Mandell IB, and Phillips JP
- Subjects
- 6-Phytase genetics, Age Factors, Animals, Animals, Genetically Modified genetics, Breeding methods, Dietary Supplements, Gene Transfer Techniques veterinary, Phosphorus metabolism, Sus scrofa genetics, Swine, 6-Phytase metabolism, Animals, Genetically Modified physiology, Body Composition physiology, Kidney physiology, Meat, Saliva metabolism, Sus scrofa physiology
- Abstract
A transgenic line of Yorkshire (YK) pigs named the Cassie (CA) line was produced with a low copy number phytase transgene inserted in the genome. The transgenic line efficiently digests P, Ca, and other major minerals of plant dietary origin. The objectives of this study were to 1) compare carcass and tissue nutrient composition and meat quality traits for third generation hemizygous CA line market BW finisher pigs (n = 24) with age-matched conventional YK finisher pigs (n = 24) and 2) examine effects of outbreeding with high-index conventional YK boars on modifying carcass leanness from the third to sixth generations in CA line finisher boars (n = 73) and gilts (n = 103). Cassie boars (n = 12) and CA gilts (n = 12) were fed diets without supplemental P and comparable numbers of age-matched YK boars and gilts fed diets containing supplement P were raised throughout the finisher phase. The pigs were slaughtered and then fabricated into commercial pork primals before meat composition and quality evaluation. Proximate and major micronutrient composition was determined on tissues including fat, kidney, lean, liver, and skin. The main difference observed was greater (P = 0.033) crude fat content in CA boar carcasses and increased (P < 0.04) leaf lard in both CA boars and gilts but no differences were observed (P = 0.895 and P = 0.223, respectively) in carcass backfat thickness as compared with YK pigs. There were no substantive differences in tissue composition, except for CA boar kidneys. Numerous changes in the mineral, fatty acid, and indispensable AA composition for CA boar kidneys were not apparent in CA gilts. These changes may point to adaptive physiological changes in the boar kidney necessary for homeostatic regulation of mineral retention related to phytase action rather than to insertion of the transgene. However, from a meat composition perspective, transgenic expression of phytase in the CA line of YK pigs had little overall effect on meat composition. Outbreeding of high-index CA gilts with high-index commercial YK boars linearly reduced (P = 0.002) back fat thickness with a corresponding linear increase (P = 0.001) in lean yield in finisher CA gilts, although no change in these parameters was observed in CA finisher boars. The increase in lean yield in CA gilts by selective breeding without affecting the level of salivary phytase activity documents the value of conventional genetic selection in conjunction with genetic modification.
- Published
- 2014
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31. Phytase properties and locations in tissues of transgenic pigs secreting phytase in the saliva.
- Author
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Forsberg CW, Meidinger RG, Murray D, Keirstead ND, Hayes MA, Fan MZ, Ganeshapillai J, Monteiro MA, Golovan SP, and Phillips JP
- Subjects
- Animals, Animals, Genetically Modified genetics, Brain metabolism, Escherichia coli enzymology, Female, Hydrogen-Ion Concentration, Intestinal Mucosa metabolism, Male, Muscle, Skeletal metabolism, Swine genetics, Tissue Distribution, 6-Phytase metabolism, Animals, Genetically Modified metabolism, Palate metabolism, Parotid Gland metabolism, Saliva metabolism, Salivary Glands metabolism, Swine metabolism
- Abstract
A transgenic Cassie (CA) line of Yorkshire (YK) pigs was developed using a transgene composed of the mouse parotid secretory protein promoter linked to the Escherichia coli phytase gene integrated in chromosome 4. Previous studies documented that salivary secretion of phytase was sufficient to enable efficient digestion of plant feed phytate P. In the present study the catalytic properties and tissue distribution of the phytase in CA pigs were determined by a combination of enzymatic assays, immunohistochemistry, and immunoblots of tissue samples. The E. coli phytase had a mass of 44.82 kDa whereas the phytase secreted in CA saliva had a mass of 52.42 kDa as a result of glycosylation of the enzyme in the parotid gland. Despite the difference in size, the 2 enzymes exhibited similar substrate specificities, and substrate affinity ( K: m) and maximum hydrolytic activity ( V: max) catalytic properties. Phytase assays showed that the enzyme was present at high specific activity in the salivary glands with low activity in the soft palate and essentially none in the kidney, lean (muscle), liver, or skin of CA pigs and none in YK pigs. This conclusion was supported by immunoblot analysis using a polyclonal anti-phytase antibody. Immunohistochemical analysis of 83 different tissue locations of CA and YK pigs confirmed the ubiquitous presence of phytase in serous cells of the salivary glands and the localized presence of phytase in both serous and mixed cell types in the submucosal glands of the oropharynx; in the pharynx, tonsils, and esophagus; in some Bowman's glands in the nasal mucosa and eustachian tube; and in the prostate gland of CA boars. Furthermore, it showed the absence of phytase from the kidney, lean, liver, and skin of CA pigs. Phytase was not detected in any of the conventional YK tissues tested. The phytase was found to be glycosylated with the allergenic galactose-α-1,3-galactose (α-gal) epitope by immunoblotting using α-gal specific monoclonal antibodies. Galactose-α-1,3-galactose glycosylation of proteins is a common feature of pork and other red meats. The α-gal epitope was shown to be associated with a few proteins in muscle and skin but with the greatest number of proteins in kidney and parotid tissues of CA and YK pigs. The absence of phytase from the major food tissues and the displacement of other α-gal glycosylated proteins in the parotid glands by α-gal glycosylated phytase in conjunction with previously published data support the contention that expression of the novel phytase has minimal influence on pork quality and safety.
- Published
- 2014
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32. Digestive utilization of phosphorus from plant-based diets in the Cassie line of transgenic Yorkshire pigs that secrete phytase in the saliva.
- Author
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Meidinger RG, Ajakaiye A, Fan MZ, Zhang J, Phillips JP, and Forsberg CW
- Subjects
- 6-Phytase genetics, Animal Feed analysis, Animal Nutritional Physiological Phenomena, Animals, Animals, Genetically Modified genetics, Animals, Genetically Modified growth & development, Animals, Genetically Modified physiology, Blood Chemical Analysis veterinary, Calcium blood, Calcium metabolism, Calcium urine, Dietary Supplements analysis, Electrolytes blood, Electrolytes urine, Feces chemistry, Male, Minerals blood, Minerals metabolism, Minerals urine, Phosphorus, Dietary blood, Phosphorus, Dietary urine, Spectrophotometry, Atomic veterinary, Sus scrofa genetics, Sus scrofa growth & development, 6-Phytase administration & dosage, 6-Phytase metabolism, Digestion, Electrolytes metabolism, Phosphorus, Dietary metabolism, Sus scrofa physiology
- Abstract
A line of transgenic Yorkshire pigs referred to as the Cassie (CA) line was generated, which possessed a stable, low copy number phytase transgene insertion that enabled phytase secretion in the saliva. This study was conducted to assess growth and efficacy for improving P, Ca, and other macromineral utilization in the CA pigs receiving diets typical of those used for commercial swine production. In Exp. 1, 12 CA boars and 12 CA gilts fed diets without supplemental P gained weight and exhibited feed efficiency similar to conventional age-matched 12 Yorkshire boars and 12 Yorkshire gilts raised on similar diets with supplemental P. Serum concentrations of P and Ca were similar for CA and Yorkshire pigs during the growing and finishing phases, indicating that the CA pigs were not P limited. In Exp. 2, 6 CA (13.1 kg BW) and 6 Yorkshire barrows (8.8 kg BW) were fed 3 diets (control; low in Ca and P; and low in Ca, P, and CP) over 3 phases. The CA barrows fed the diet without supplemental P retained 25 to 40% (P < 0.001), 77 to 91% (P < 0.001), and 27 to 56% (P < 0.001) more P during the weaning, growing, and finishing phases, respectively, than conventional Yorkshire barrows fed similar diets without supplemental P. In Exp. 3, CA and Yorkshire barrows of similar ages weighing 66.2 ± 1.7 kg (n = 10) and 50.0 ± 1.0 kg (n = 10), respectively, were used. The P retention of CA finisher barrows fed a diet without supplemental P was 34% greater (P < 0.001) than conventional Yorkshire barrows fed the same diet with 750 units of exogenous phytase/kg diet. Urinary Ca to P ratio in the CA pigs was 0.27, whereas that for the Yorkshire barrows was 30, thereby, indicating that the Yorkshire barrows suffered a P deficiency. Furthermore, digestive utilization of major electrolyte macrominerals, K and Na, was improved (P < 0.05) by 18 and 16%, respectively, in the CA finisher pigs compared with the conventional Yorkshire finisher pigs fed phytase; however, only K exhibited enhanced retention. In conclusion, the CA line pigs secrete sufficient phytase from the salivary glands to enable efficient digestion of plant P, Ca, and major electrolyte macrominerals.
- Published
- 2013
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33. Synthesis and antiviral activity of conformational analogues of leucamide A.
- Author
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Wang WL, Chen HJ, Ma WP, Gu M, Fan MZ, Li JY, Feng B, and Nan FJ
- Subjects
- Humans, Molecular Conformation, Molecular Structure, Structure-Activity Relationship, Antiviral Agents chemical synthesis, Antiviral Agents chemistry, Antiviral Agents pharmacology, Influenza A virus drug effects, Influenza, Human drug therapy, Peptides, Cyclic chemical synthesis, Peptides, Cyclic chemistry, Peptides, Cyclic pharmacology
- Abstract
In order to study the effect of heterocyclic core conformational state of leucamide A on its anti-influenza virus A activity, five conformational analogues were prepared by replacing the Pro-Leu dipeptide in the molecule with various amino acids. The amino acids used were of 2 to 6 carbons. The results showed that these replacements not only changed the conformational relationship between the 4,2-bisheterocycle tandem pair and the third heterocycle, but also had dramatic effect on its activity against influenza virus A.
- Published
- 2012
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34. Responses of dietary ileal amino acid digestibility to consumption of different cultivars of potatoes and conventional fibers in grower pigs fed a high-fat basal diet.
- Author
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Wang Q, Yang X, Leonard S, Archbold T, Sullivan JA, Duncan AM, Ma WD, Bizimungu B, Murphy A, Htoo JK, and Fan MZ
- Subjects
- Animal Feed analysis, Animal Nutritional Physiological Phenomena, Animals, Diet veterinary, Dietary Fats administration & dosage, Dietary Fats metabolism, Dietary Fats pharmacology, Dietary Fiber analysis, Male, Amino Acids metabolism, Dietary Fiber metabolism, Digestion physiology, Ileum physiology, Solanum tuberosum chemistry, Swine physiology
- Abstract
Whereas dietary fibers are well recognized for nutritional management of human health issues, fiber is also known to be one of the dietary factors potentially affecting digestive use of dietary proteins. As a staple food, potato (Solanum tuberosum) may be a significant dietary fiber source. The objective of this study was to examine effects of dietary supplementation of six potato cultivar-genotype samples that differ in soluble fiber content and two conventional fiber components (i.e., cellulose and guar gum) on the apparent ileal AA digestibility in pigs fed a high-fat basal diet. The basal diet was formulated as a zero-fiber negative control (NC) to contain 41.5% poultry meal, 4% casein, 15% animal fat-oil blend, 2.8% sucrose, 31% corn (Zea mays) starch, 0.50% salt, and 0.40% trace mineral-vitamin supplement with fat contributing to 47% of the dietary GE. The two fiber diets were formulated by respectively diluting the basal diet with 10% guar gum and 10% cellulose at the expense of corn starch. Six other test diets were formulated by including 8.5% guar gum and further diluting the basal diet with 25.1% one of the six cultivar-genotype samples of dehydrated potato tuber powder to contain about 10% total dietary fiber at the expense of corn starch. Eighty-one 25-kg barrows were fitted with a simple T-cannula at the distal ileum and fed the diets according to a completely randomized block design with each block lasting 28 d. Compared with the NC, the ileal digestibility of Ala, Gly, and Pro were decreased (P < 0.05) by 10% guar gum whereas the digestibility of Gly was reduced (P < 0.05) by 10% cellulose. The ileal digestibility of several AA was decreased (P < 0.05) by the test potatoes plus 8.5% guar gum compared with the NC. Our results suggest that dietary inclusion of fiber at 10% from guar gum and cellulose and contributed by potatoes may adversely affect digestive use of dietary protein.
- Published
- 2012
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35. The porcine gut microbial metagenomic library for mining novel cellulases established from growing pigs fed cellulose-supplemented high-fat diets.
- Author
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Wang W, Archbold T, Kimber MS, Li J, Lam JS, and Fan MZ
- Subjects
- Animal Nutritional Physiological Phenomena, Animals, Bacteria classification, Cellulases genetics, Cellulose metabolism, Diet veterinary, Dietary Fats administration & dosage, Dietary Supplements, Dose-Response Relationship, Drug, Gastrointestinal Contents microbiology, Gene Expression Regulation, Bacterial, Gene Expression Regulation, Enzymologic, Genome, Bacterial, Animal Feed analysis, Bacteria genetics, Cellulases metabolism, Cellulose chemistry, Genomic Library, Swine physiology
- Abstract
The porcine gut microbiome is a novel genomic resource for screening cellulose-degrading enzymes. A plasmid metagenomic expression library was constructed from the hindgut microbiota of 6 Yorkshire growing pigs (25 to 40 kg) fed a high-fat basal diet supplemented with 10% Solka-Floc for 28 d. Fresh cecal and colonic digesta samples were collected, flash-frozen in liquid N, and stored under -80°C. Metagenomic DNA was extracted, mechanically sheared, and cleaned to remove small DNA fragments (<1.0 kb). The resulting DNA fragments were subjected to blunt-end polishing, fractionation, and purification by using commercial kits. The end-modified DNA fragments were ligated to pCR4Blunt-TOPO vector and transformed into competent Escherichia coli TOPO10 cells. Metagenomic plasmid libraries were screened for carboxymethyl cellulolytic activities by using lysogeny broth agar plates. The average insert size of the resulting library was approximately 4.2 kb. Screening for the ability to hydrolyze carboxymethyl cellulose yielded 14 positive colonies, giving an estimated 430 Mb of metagenomic DNA in the approximately 102,000 E. coli clones with an overall hit rate of 0.14%. The 11 assembled insert sequences included 4 function-related gene clusters, and a total of 18 putative carbohydrate active enzyme genes were identified. This included genes encoding 11 cellulases, 4 hemicellulases, 1 polygalacturonas, 1 glycoside hydrolase family 26 mannanase-family 5 cellulase chimeric enzyme gene, and 1 cellobiose phosphorylase. In conclusion, the coupling of functional metagenomic mining with biochemical characterization of fiber-degrading enzymes is a powerful strategy for exploring the enzymological underpinnings of the anaerobic fermentation of dietary fiber in the complex animal gut environment.
- Published
- 2012
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36. Consumption of guar gum and retrograded high-amylose corn resistant starch increases IL-10 abundance without affecting pro-inflammatory cytokines in the colon of pigs fed a high-fat diet.
- Author
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Fan MZ, Archbold T, Lackeyram D, Liu Q, Mine Y, and Paliyath G
- Subjects
- Amylose chemistry, Animal Nutritional Physiological Phenomena, Animals, Colon metabolism, Diet veterinary, Galactans pharmacology, Gene Expression Regulation drug effects, Interleukin-10 genetics, Male, Mannans pharmacology, Plant Gums pharmacology, Transcriptome, Zea mays chemistry, Animal Feed analysis, Dietary Fats pharmacology, Galactans chemistry, Interleukin-10 metabolism, Mannans chemistry, Plant Gums chemistry, Starch chemistry, Swine physiology
- Abstract
Increases in dietary intake of viscous and nonviscous soluble fiber are reported to improve bowel health. However, related biological mechanisms are not very clear. This study was conducted to examine if colonic inflammation would occur in a typical Western diet model and determine if consumption of soluble fiber components would attenuate potential detrimental effects by differentially affecting colonic abundances of anti-inflammatory cytokine IL-10 and 2 pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and IL-6 in pigs fed a high-fat basal diet supplemented, respectively, with 15% viscous soluble fiber guar gum (GG) and 15% nonviscous soluble fiber, that is, retrograded high-amylose corn (Zea mays) resistant starch (RS). A total of 24 Yorkshire growing barrows were assigned into a standard corn and soybean (Glycine max) meal (SBM)-based grower diet as a positive control (PC), an animal protein-based high-fat basal diet as the negative control (NC), and 2 NC basal diets supplemented with 15% GG and 15% RS, respectively, according to a completely randomized block design for 4 wk. Abundance of these cytokines in homogenized and extracted colonic tissue supernatant samples was measured by ELISA. Although colonic IL-10 abundance was lower (P < 0.05) in the corn and SBM-based PC group than that in the high-fat basal NC group, there were no differences (P > 0.05) in colonic abundances of TNF-α and IL-6 between NC and PC groups and among all of the treatment groups. Compared with the NC group, consumption of GG and RS at 15% increased (P < 0.05) colonic IL-10 abundance. Moreover, there was no difference (P > 0.05) in colonic IL-10 abundance between the 15% GG and the 15% RS groups. Thus, consumption of a typical high-fat Western diet did not induce colonic inflammation. Diets supplemented with 15% GG or 15% RS may protect the colon from developing inflammation by enhancing IL-10 abundance.
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- 2012
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37. The in vivo infusion of hydrogen peroxide induces oxidative stress and differentially affects the activities of small intestinal carbohydrate digestive enzymes in the neonatal pig.
- Author
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Lackeyram D, Mine Y, Widowski T, Archbold T, and Fan MZ
- Subjects
- Animals, Female, Glutathione blood, Glutathione metabolism, Oxidative Stress, Animals, Newborn, Carbohydrate Metabolism physiology, Hydrogen Peroxide pharmacology, Intestine, Small enzymology, Swine physiology
- Abstract
Chronic fatigue syndrome (CFS) is characterized by persistent and relapsing fatigue that involves oxidative stress in its pathogenesis. We tested the hypothesis that a decrease in key carbohydrate-digesting enzyme activity in the gut is one of the major biological mechanisms of developing CFS in liquid formula-fed neonatal pigs with in vivo infusion of H(2)O(2). Piglets at 7 to 10 d of age were fitted with an intraperitoneal catheter, allowed a 3-d post surgical recovery, and infused with either H(2)O(2) at 5 mmol/kg BW (PER; n = 8) or the same volume of saline (CON; n = 8) in six 20-ml doses daily for a period of 10 d. During this period, animal behavior was monitored, blood samples collected, and jejunal enzyme activity kinetic experiments for lactase, sucrase, maltase, and maltase-glucoamylase were conducted. Plasma concentration of reduced glutathione remained similar (P > 0.05) to the pre-infusion level over the study duration in the CON group whereas this was 65% lower (P < 0.05) than the pre-infusion level in the PER group. Piglets experiencing oxidative stress had an overall lower (P < 0.05) physical mobility and the maximal jejunal specific activities [μmol/(mg protein · min)] for lactase (PER, 6.54 ± 0.68 vs. CON, 12.65 ± 0.69) and maltase (PER, 57.39 ± 1.02 vs. CON, 75.60 ± 1.04), respectively. However, differences were not observed (P > 0.05) in the maximal specific activities [μmol/(mg protein · min)] of sucrase (PER, 10.50 ± 1.37 vs. CON, 12.40 ± 1.55) and maltase-glucoamylase (PER, 0.71 ± 0.08 vs. CON, 0.70 ± 0.07) between the 2 groups. In conclusion, infusion of a suitable dose of H(2)O(2) induced CFS in the neonatal pigs. Oxidative stress in vivo differentially affected the maximal activities of important small intestinal carbohydrate-digesting enzymes in neonatal pigs fed a dairy milk-based liquid formula.
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- 2012
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38. The small intestinal apical hydrolase activities are decreased in the piglet with bowel inflammation induced by dextran sodium sulfate.
- Author
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Lackeyram D, Mine Y, Archbold T, and Fan MZ
- Subjects
- Animals, Female, Gene Expression Regulation, Enzymologic, Hydrolases genetics, Inflammation chemically induced, Intestine, Small pathology, Swine, Swine Diseases enzymology, Dextran Sulfate toxicity, Hydrolases metabolism, Inflammation veterinary, Intestine, Small enzymology, Swine Diseases chemically induced
- Abstract
Inflammatory bowel disease (IBD) is characterized by cramping, abdominal pain, bloating, constipation, and diarrhea. We tested the hypothesis that compromised activities of the major small intestinal apical hydrolases contribute to the symptoms of IBD. Changes in hydrolytic kinetics, target protein abundances, and mRNA expression of intestinal alkaline phosphatase (IAP), lactase, maltase, sucrase-isomaltase (SI), maltase-glucoamylase (MGA), and aminopeptidase N (APN) in piglets with colonic inflammation chemically induced by dextran sodium sulfate (DSS) were investigated. Yorkshire piglets at 5 d of age, with an average initial BW of about 3 kg, were fitted with intragastric catheters and were divided into control (CON; n = 6) and treatment groups (DSS; n = 5). Both groups were infused with an equal volume of either saline or 1.25 g of DSS · kg BW(-1) · d(-1) in saline, respectively, for 10 d. Enzyme kinetic experiments for IAP, lactase, maltase, SI, MGA, and APN were measured at 37°C with isolated proximal jejunal apical membrane. Target hydrolase protein abundances in the apical membrane were analyzed by Western blotting and their mRNA abundances in the jejunum were measured by quantitative real-time reverse transcription (RT-) PCR with β-actin as the housekeeping gene. Expressed as percentage of the CON, DSS treatment decreased (P < 0.05) the maximal specific activities of IAP (53%), lactase (78%), maltase (56%), SI (72%), MGA (29%), and APN (22%) as well as the target hydrolase protein abundances of IAP (39%), lactase (35%), SI (36%), and APN (54%), respectively. Decreases (P < 0.05) in the mRNA abundances (% of the CON) for lactase (25%), SI (52%), MGA (75%), and APN (39%) were observed in the DSS group. However, DSS treatment increased (P < 0.05) the jejunal IAP mRNA abundance by 3.5 fold. We conclude that decreases in the small intestinal apical activities of these examined hydrolases likely contribute to overgrowth of pathogenic bacterial populations in the distal small intestine and the colon, leading to the pathogenesis of IBD.
- Published
- 2012
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39. Effects of dietary true digestible calcium to phosphorus ratio on growth performance and efficiency of calcium and phosphorus use in growing pigs fed corn and soybean meal-based diets.
- Author
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Fan MZ and Archbold T
- Subjects
- Animal Nutritional Physiological Phenomena, Animals, Calcium chemistry, Calcium, Dietary analysis, Calcium, Dietary metabolism, Diet veterinary, Male, Phosphorus chemistry, Phosphorus, Dietary analysis, Phosphorus, Dietary metabolism, Swine metabolism, Animal Feed analysis, Calcium metabolism, Phosphorus metabolism, Glycine max, Swine growth & development, Zea mays
- Abstract
Objectives of this study were to determine effects of dietary true fecal digestible Ca to true digestible P ratio on growth performance and efficiency of Ca and P use in growing pigs fed corn (Triticum aestivum)-soybean (Glycine max) meal (SBM)-based diets. Experiment 1 was carried out to measure true fecal digestibility of Ca and P as well as the fecal endogenous outputs of these nutrients associated with a corn and SBM-based diet in 12 Yorkshire growing pigs with an average initial BW of 23.2 ± 0.6 kg by the substitution method. True fecal digestibility values (%; n = 6) of Ca (53.6 ± 12.7) and P (43.8 ± 16.7) as well as the fecal endogenous outputs (g/kg DMI; n = 12) of Ca (0.91 ± 0.20) and P (1.31 ± 0.15) associated with the diets were determined. Experiment 2 was conducted with 36 Yorkshire barrows of an average initial BW of 24.2 ± 0.6 kg and the pigs were fed 6 diets according to a completely randomized block design. The 6 diets were corn and SBM based with diet 1 containing 0.2% true digestible Ca and 0.3% true digestible P and were formulated to contain 6 total Ca to total P ratios based on analyzed dietary Ca and P contents (diet 1, 0.6:1; diet 2, 0.7:1; diet 3, 0.8:1; diet 4, 1.3:1; diet 5, 1.0:1; and diet 6, 1.3:1) by supplementing gradient levels of limestone with a constant dietary P content for meeting the recommended requirement. Changes in the dietary Ca to P ratio had no effects (P > 0.05) on ADG. No differences (P > 0.05) in ADFI were observed between the other diets except the lower ADFI (P < 0.05) in diet 3 compared with diet 2. However, G:F was higher (P < 0.05) in diet 2 compared with diets 5 and 6. Changes in the dietary Ca to P ratio had consistent effects on true fecal P digestibility and retention with much lower values (P < 0.05) observed in diet 5 in comparison with the other diets. In summary, true fecal digestible Ca to P ratios of 0.9:1 to 1.0:1 were associated with optimal responses in both G:F as well as true fecal P digestibility and retention in growing pigs fed corn and SBM-based diets.
- Published
- 2012
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40. Characterization of L-lysine transport across equine and porcine jejunal and colonic brush border membrane.
- Author
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Woodward AD, Fan MZ, Geor RJ, McCutcheon LJ, Taylor NP, and Trottier NL
- Subjects
- Animals, Biological Transport, Active physiology, Time Factors, Tissue Culture Techniques, Colon physiology, Horses physiology, Jejunum physiology, Lysine metabolism, Microvilli physiology, Swine physiology
- Abstract
In nonruminant herbivores, microbially derived AA could contribute to whole-body AA homeostasis and thus decrease predicted AA requirements. However, postileal capacity of AA uptake is currently unknown. Therefore, to test the hypothesis that Lys is transported across the large colon mucosal apical membrane with capacity similar to that of the small intestinal mucosa in the pony and pig, we examined Lys transport in vitro using brush border membrane vesicles (BBMV). Mucosa was collected from the distal jejunum (DJ) and proximal large colon (PLC) of growing pigs (n = 3) and ponies (n = 4), flash frozen in liquid nitrogen, and stored at -80°C. Jejunal and colonic BBMV were manufactured by Mg(2+) precipitation and used to determine initial rates and kinetics [the maximal transport rate (V(max)) and the Michaelis constant (K(M))] of l-Lys transport into apical epithelia by rapid filtration technique in Na(+)-gradient incubation buffer. Initial rates of total l-Lys uptake did not differ between the PLC and DJ in either the pig or the pony, or between the pony and the pig, at each l-Lys concentration. In the pig, compared with the DJ, l-Lys transport V(max) in the PLC did not differ (121 ± 26 and 180 ± 26 pmol•mg of protein(-1)•s(-1), respectively; P = 0.14) and l-Lys K(M) in the PLC tended to be greater (0.23 ± 0.22 and 0.89 ± 0.22 mM, respectively; P = 0.09). In the pony, compared with the DJ, l-Lys transport V(max) in the PLC was greater (62 ± 25 and 149 ± 25 pmol•mg of protein(-1)•s(-1), respectively; P = 0.04) and l-Lys K(M) in the PLC was greater (0.08 ± 0.22 and 1.05 ± 0.22 mM, respectively; P = 0.02). l-Lysine diffusion was not different between segments; however, total intestinal diffusion was greater (P = 0.03) in the pony than in the pig (115 ± 10 and 73 ± 10 pmol·mg of protein(-1)•s(-1), respectively). These results demonstrate that the large colon is capable of l-Lys transport across the apical epithelial membrane with greater capacity and less affinity than the jejunum, indicating that the large colon may play a significant role in l-Lys absorption and homeostasis in hindgut fermenters.
- Published
- 2012
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41. [Effects of Beauveria bassiana on Myzus persicae and its two predaceous natural enemies].
- Author
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Zhu H, Luo XM, Song JX, Fan MZ, and Li ZZ
- Subjects
- Animals, Coleoptera physiology, Prunus parasitology, Aphids microbiology, Aphids physiology, Beauveria physiology, Pest Control, Biological methods, Predatory Behavior physiology
- Abstract
A Beauveria bassiana strain Bb21 was isolated from naturally infected green peach aphid Myzus persicae (Hemiptera: Aphididae). The effects of the strain on M. persicae and its two predaceous natural enemies Chrysoperla carnea (Neuroptera: Chrysopidae) and Harmonia axyridis (Coleoptera: Coccinellidae) were investigated under laboratory conditions. Bb21 had strong pathogenicity to M. persicae, with the LD50 of 97 conidia x mm(-2) (45-191, 95% confidence interval), but was less pathogenic to the second instar nymph of C. carnea, with the LD50 of 1089 conidia x mm(-2). The LD50 for C. carnea was 10.2 times higher than that for M. persicae. The pathogenicity of Bb21 to H. axyridis was very weak, with a low infection rate of 13% even at a high concentration 5 x 10(8) conidia x mL(-1). The Bb21 at low conidia concentration had less effect on the developmental period and fecundity of the two predaceous natural enemies. However, when applied at the high concentration 5 x 10(8) spores x mL(-1), Bb21 shortened the larval stage of H. axyridis averagely by 1.4 d and decreased the adult emergence rate and fecundity by 33% and 14%, respectively, and shortened the larval stage of C. carnea averagely by 0.7 d and decreased the adult emergence rate and fecundity by 24% and 11%, respectively. Since the LD50 for green peach aphid was much lower than that for the two predaceous natural enemies, and had very low effect on the adult emergence rate and fecundity of the two predators at the concentration recommended for field spray, Bb21 could be applied as a biocontrol agent of M. persicae in the integrated management of pernicious organisms.
- Published
- 2011
42. [Perioperative monitoring and control of hyperglycemia during deep hypothermic circulatory arrest].
- Author
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He B, Wang J, Xu ZY, Zou LJ, Shao WY, Chen JY, Fan MZ, Liu Y, Li BL, and Zhang BR
- Subjects
- Blood Glucose metabolism, Female, Humans, Lactic Acid metabolism, Male, Middle Aged, Circulatory Arrest, Deep Hypothermia Induced, Hyperglycemia etiology, Hyperglycemia prevention & control, Perioperative Care
- Abstract
Objective: To observe the trend of change in perioperative blood glucose level in patients undergoing deep hypothermic circulatory arrest (DHCA), in order to evaluate the influencing factors of inciting hyperglycemia and the clinical effects of insulin control., Methods: In the Department of Cardiothoracic Surgery of Changhai Hospital, 176 patients underwent aortic operation under DHCA from January 2000 to January 2010. Blood glucose, arterial blood gas and lactate levels were determined at four time points, including pre-cardiopulmonary bypass (CPB), pre-DHCA, post-DHCA, and at admission to intensive care unit (ICU). Hyperglycemia after surgery was controlled at the level of 6-8 mmol/L by intermittent subcutaneous injection or intravenous micropump injection of insulin. At the same time, the cumulative amount of insulin within 24 hours after surgery was recorded., Results: The blood glucose (mmol/L) level at pre-DHCA time point was significantly higher than that of pre-CPB (9.62 ± 1.79 vs. 5.04 ± 1.401,P<0.05), and the blood glucose level was further elevated at the time point of post-DHCA (14.91 ± 2.36,P<0.01) and in-ICU (15.32 ± 2.47) compared with that of pre-CPB (P<0.01). The level of blood glucose elevation was positively correlated with blood lactate level. One hundred and thirty-four patients (76.1%) insulin was given with intravenous micropump due to poor effect of intermittent subcutaneous injection of insulin in controlling blood glucose. Among whom 30 patients (17.0%) developed the phenomenon of insulin resistance. Perioperative hyperglycemia during DHCA was associated with old age (≥ 50 years old), primary hypertension, serious aortic valve disease, diabetes or coronary heart disease, emergency operation, CPB time ≥ 3 hours and DHCA time ≥ 45 minutes. The cumulative amount of insulin within 24 hours after surgery was increased significantly. The results of blood glucose (mmol/L) in-ICU were as follows : age ≥ 50 years old or < 50 years old (18.66 ± 2.52 vs. 12.90 ± 2.27); hypertension with and without (18.98 ± 2.55 vs. 12.31 ± 2.34); serious aortic valve disease with and without (19.59 ± 2.95 vs. 12.13 ± 2.23); diabetes with and without (20.62 ± 1.76 vs. 11.75 ± 1.11); coronary heart disease with and without (19.77 ± 2.98 vs. 12.01 ± 2.02); emergency operation with and without (19.78 ± 1.97 vs. 12.23 ± 1.38); CPB time ≥ 3 hours or < 3 hours (19.86 ± 1.89 vs. 11.70 ± 1.15); DHCA time ≥ 45 minutes or < 45 minutes (19.92 ± 1.88 vs. 11.64 ± 1.12), and all of them should statistical difference (all P < 0.05). The cumulative amount of insulin (U) within 24 hours after surgery was as follows: age ≥ 50 years old or < 50 years old (169.5 ± 56.6 vs. 110.2 ± 38.5); hypertension with and without (171.6 ± 64.0 vs. 104.8 ± 34.3); aortic valve disease with and without (171.4 ± 36.8 vs. 109.4 ± 27.6); diabetes with and without (202.5 ± 46.7 vs. 100.4 ± 31.5); coronary heart disease with and without (178.5 ± 38.6 vs. 104.6 ± 26.4 ); emergency operation with and without (178.3 ± 35.7 vs. 102.7 ± 26.8); CPB time ≥ 3 hours or < 3 hours (168.6 ± 37.2 vs. 107.3 ± 27.5); DHCA time ≥ 45 minutes or < 45 minutes (172.5 ± 36.1 vs. 105.4 ± 28.7), and all of them showed significant statistical difference (all P < 0.05). and all of them showed significant statistical difference (all P < 0.05)., Conclusion: DHCA may cause significant increase in perioperative blood glucose and lactate, and even may lead to insulin resistance. Patients often require continuous intravenous administration of large doses of insulin. Perioperative hyperglycemia during DHCA is related to many factors, which should be considered in control of blood glucose.
- Published
- 2011
43. Apical Na+-D-glucose cotransporter 1 (SGLT1) activity and protein abundance are expressed along the jejunal crypt-villus axis in the neonatal pig.
- Author
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Yang C, Albin DM, Wang Z, Stoll B, Lackeyram D, Swanson KC, Yin Y, Tappenden KA, Mine Y, Yada RY, Burrin DG, and Fan MZ
- Subjects
- Animals, Intestinal Mucosa cytology, Kinetics, Swine, Animals, Newborn metabolism, Intestinal Mucosa metabolism, Jejunum metabolism, Sodium-Glucose Transporter 1 metabolism
- Abstract
Gut apical Na(+)-glucose cotransporter 1 (SGLT1) activity is high at the birth and during suckling, thus contributing substantially to neonatal glucose homeostasis. We hypothesize that neonates possess high SGLT1 maximal activity by expressing apical SGLT1 protein along the intestinal crypt-villus axis via unique control mechanisms. Kinetics of SGLT1 activity in apical membrane vesicles, prepared from epithelial cells sequentially isolated along the jejunal crypt-villus axis from neonatal piglets by the distended intestinal sac method, were measured. High levels of maximal SGLT1 uptake activity were shown to exist along the jejunal crypt-villus axis in the piglets. Real-time RT-PCR analyses showed that SGLT1 mRNA abundance was lower (P < 0.05) by 30-35% in crypt cells than in villus cells. There were no significant differences in SGLT1 protein abundances on the jejunal apical membrane among upper villus, middle villus, and crypt cells, consistent with the immunohistochemical staining pattern. Higher abundances (P < 0.05) of total eukaryotic initiation factor 4E (eIF4E) protein and eIE4E-binding protein 1 γ-isoform in contrast to a lower (P < 0.05) abundance of phosphorylated (Pi) eukaryotic elongation factor 2 (eEF2) protein and the eEF2-Pi to total eEF2 abundance ratio suggest higher global protein translational efficiency in the crypt cells than in the upper villus cells. In conclusion, neonates have high intestinal apical SGLT1 uptake activity by abundantly expressing SGLT1 protein in the epithelia and on the apical membrane along the entire crypt-villus axis in association with enhanced protein translational control mechanisms in the crypt cells.
- Published
- 2011
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44. Long-term preservation, regeneration, and cultivation of Paecilomyces tenuipes (Peck) Samson (Ascomycetes), an entomopathogenic fungus inoculated into the silkworm larva of Bombyx mori.
- Author
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Nam SH, Li CR, Li ZZ, Fan MZ, Kang SW, Lee KG, Yeo JH, Hwang JS, Choi JY, Han SM, and Lee KM
- Subjects
- Animals, Fruiting Bodies, Fungal radiation effects, Larva microbiology, Light, Paecilomyces isolation & purification, Paecilomyces radiation effects, Pupa microbiology, Spores, Fungal growth & development, Temperature, Bombyx microbiology, Fruiting Bodies, Fungal growth & development, Mycelium growth & development, Paecilomyces growth & development, Preservation, Biological methods
- Abstract
Paecilomyces tenuipes reportedly have anticancer and immune activities, along with various other medicinal uses. Cultured products with P. tenuipes are certified for use in food in South Korea, and processed goods containing this fungus have been developed in many countries, particularly South Korea, Japan, and China. Research on mass production technology-procured raw materials for the manufacture of P. tenuipes is very important; however, cultures of the fungus have been unstable. This study identified stable cultivation conditions, focusing on growth inhibition and revitalization. Moisture regulation and preservation of pupae inoculated with P. tenuipes were used to control growth inhibition and revitalization. When inoculated silkworm pupae were dehydrated to 4% moisture and preserved freeze-dried or at -70 degrees C, -20 degrees C, or 4 degrees C, the mycelia in their bodies were able to survive for 14 d. Inoculated silkworm pupae were rehydrated for 3 h and the mycelia within their bodies were recovered at 94.3-96.3%. Silkworm pupae at 4% moisture were able to survive for 135 d at temperatures < 4 degrees C and for 1 y after freeze-drying. Optimal conditions for synnemata induction were 25 degrees C and 100-300 1x.
- Published
- 2011
- Full Text
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45. [Biocathode denitrification in a two-columnar microbial fuel cell].
- Author
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Liang P, Zhang L, Huang X, Fan MZ, and Cao XX
- Subjects
- Nitrites isolation & purification, Oxygen isolation & purification, Oxygen metabolism, Bioelectric Energy Sources, Cations, Denitrification physiology, Nitrates metabolism, Nitrites metabolism
- Abstract
The biocathode of the two-columnar microbial fuel cell was used to denitrify. Factors influencing denitrification performance and power production were studied. When the external resistance decreased from 50 omega to 5 omega, the nitrate removal rate increased from 0.26 mg/(L x h) to 0.76 mg/(L x h). The nitrite accumulated to 55 mg/L with the external resistance decreasing to 5 omega. The nitrate degradation followed the zero order reaction model when the initial nitrate concentration was 20-120 mg/L. The power generation was not affected by the nitrate concentration distinctly. The nitrite concentration increased with the initial nitrate concentration. The nitrite removal could be enhanced by adding organic matter, without significant influence on the power generation.
- Published
- 2010
46. Egg yolk peptides up-regulate glutathione synthesis and antioxidant enzyme activities in a porcine model of intestinal oxidative stress.
- Author
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Young D, Fan MZ, and Mine Y
- Subjects
- Animals, Antioxidants metabolism, Caco-2 Cells, Catalase genetics, Catalase metabolism, Cell Line, Tumor, Egg Proteins chemistry, Female, Glutamate-Cysteine Ligase genetics, Glutamate-Cysteine Ligase metabolism, Humans, Intestinal Mucosa metabolism, Intestines drug effects, Male, Superoxide Dismutase genetics, Superoxide Dismutase metabolism, Swine, Egg Proteins pharmacology, Gene Expression Regulation, Enzymologic drug effects, Glutathione biosynthesis, Intestines enzymology, Oxidative Stress drug effects, Peptides pharmacology, Up-Regulation drug effects
- Abstract
Long-term oxidative stress in the gastrointestinal tract can lead to the development of chronic intestinal disorders. Many food-derived antioxidants are effective in vitro, but the variable reports of in vivo efficacy and the pro-oxidant nature of some antioxidants necessitate alternative strategies for the reduction of in vivo oxidative stress. Compounds that up-regulate the production of endogenous antioxidants such as glutathione (GSH) and antioxidant enzymes provide novel approaches for the restoration of redox homeostatis. Egg yolk peptides (EYP) prepared from Alcalase and protease N digestion of delipidated egg yolk proteins were found to exhibit antioxidative stress properties. The effect of EYP supplementation was examined in a hydrogen peroxide-induced human colon cell line and in an animal model of intestinal oxidative stress. EYP significantly reduced the pro-inflammatory cytokine, IL-8, in Caco-2 cells. In piglets given intraperitoneal infusions of hydrogen peroxide, EYP treatment increased GSH and gamma-glutamylcysteine synthetase mRNA expression and activity, significantly increased antioxidant enzyme activities, in particular catalase and glutathione S-transferase activities, and reduced protein and lipid oxidation in the duodenum, jejunum, ileum, and colon. Furthermore, EYP boosted the systemic antioxidant status in blood by increasing the GSH concentration in red blood cells. These results suggest that EYP supplementation is a novel strategy for the reduction of intestinal oxidative stress.
- Published
- 2010
- Full Text
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47. l-Tryptophan exhibits therapeutic function in a porcine model of dextran sodium sulfate (DSS)-induced colitis.
- Author
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Kim CJ, Kovacs-Nolan JA, Yang C, Archbold T, Fan MZ, and Mine Y
- Subjects
- Animal Nutrition Sciences, Animals, Apoptosis, Body Weight, Disease Models, Animal, Inflammation, Interleukin-6 metabolism, Mannitol chemistry, Permeability, Swine, Tumor Necrosis Factor-alpha metabolism, Colitis chemically induced, Colitis drug therapy, Dextrans pharmacology, Sulfates pharmacology, Tryptophan therapeutic use
- Abstract
Conventional therapies for the treatment of inflammatory bowel disease (IBD) have demonstrated limited efficacy and potential toxicity; therefore, there is a need for novel therapies that can safely and effectively treat IBD. Recent evidence has indicated that amino acids may play a role in maintaining gut health. L-tryptophan has been shown to reduce oxidative stress and improve neurological states. The objective of this study was to assess the therapeutic effects of L-tryptophan in a porcine model of dextran sodium sulfate (DSS)-induced colitis. DSS was administered to piglets via intragastric catheter for 5 days followed by tryptophan administration at 80% of the daily recommended intake. The severity of colitis was assessed macroscopically and histopathologically, and intestinal permeability was monitored in vivo by D-mannitol analysis. The effect of tryptophan on the local expression of key mediators of inflammation and IBD pathogenesis was examined at the protein and gene expression levels. Supplementation with tryptophan ameliorated clinical symptoms and improved weight gain to feed intake conversion ratios. Histological scores and measurements were also improved, and gut permeability was notably reduced in tryptophan-supplemented animals. Moreover, tryptophan reduced the expression of the pro-inflammatory cytokines tumor necrosis factor-alpha, interleukin (IL)-6, interferon (IFN)-gamma, IL-12p40, IL-1beta and IL-17, as well as IL-8 and intracellular adhesion molecule-1, and resulted in increased expression of apoptosis initiators caspase-8 and Bax. These results demonstrate that L-tryptophan supplementation can reduce inflammation and enhance the rate of recovery in DSS-induced colitis and may be an effective immunomodulating agent for the treatment of IBD., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)
- Published
- 2010
- Full Text
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48. Early weaning reduces small intestinal alkaline phosphatase expression in pigs.
- Author
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Lackeyram D, Yang C, Archbold T, Swanson KC, and Fan MZ
- Subjects
- Age Distribution, Alkaline Phosphatase genetics, Animal Husbandry, Animals, Female, Male, Alkaline Phosphatase metabolism, Gene Expression Regulation, Enzymologic physiology, Intestine, Small enzymology, Swine metabolism, Weaning
- Abstract
Expression of the small intestinal alkaline phosphatase (IAP) is enterocyte differentiation dependent and plays essential roles in the detoxification of pathogenic bacterial lipopolysaccharide endotoxin, maintenance of luminal pH, organic phosphate digestion, and fat absorption. This study was conducted to examine the effect of early weaning on adaptive changes in IAP digestive capacity (V(cap)) and IAP gene expression compared with suckling counterparts in pigs at ages 10-22 d. Weaning decreased (P < 0.05) IAP enzyme affinity by 26% and IAP maximal enzyme activity by 22%, primarily in the jejunal region, with the jejunum expressing 84-86% of the whole gut mucosal IAP V(cap) [mol/(kg body weight.d)]. The majority (98%) of the jejunal mucosal IAP maximal activity was associated with the apical membrane and the remaining (2%) existed as the intracellular soluble IAP. Weaning reduced the abundance of the 60-kDa IAP protein associated with the proximal jejunal apical membrane by 64% (P < 0.05). Furthermore, weaning reduced (P < 0.05) the relative abundance of the proximal jejunal IAP mRNA by 58% and this was in association with decreases (P < 0.05) in the abundances of cytoplasmic (27%) and nuclear (29%) origins of IAP caudal-associated homeobox transcription factor 1. In conclusion, early weaning decreased small intestinal IAP V(cap), IAP catalytic affinity, and IAP gene expression, and this may in part contribute to the susceptibility of early-weaned piglets to increased occurrence of enteric diseases and growth-check.
- Published
- 2010
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49. Resistance patterns and detection of aac(3)-IV gene in apramycin-resistant Escherichia coli isolated from farm animals and farm workers in northeastern of China.
- Author
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Zhang XY, Ding LJ, and Fan MZ
- Subjects
- Animals, Chickens, China epidemiology, Drug Resistance, Bacterial, Escherichia coli Infections epidemiology, Humans, Nebramycin pharmacology, Occupational Exposure, Poultry Diseases epidemiology, Poultry Diseases microbiology, Swine, Swine Diseases epidemiology, Swine Diseases microbiology, Anti-Bacterial Agents pharmacology, Escherichia coli drug effects, Escherichia coli genetics, Escherichia coli Infections microbiology, Nebramycin analogs & derivatives
- Abstract
The aminoglycoside apramycin has been used widely in animal production in China since 1999. This study was aimed to investigate the resistance pattern of apramycin-resistant Escherichia coli isolated from farm animals and farm workers in northeastern of China during 2004-2007 and to determine whether resistance to apramycin was mediated by plasmid containing the aac(3)-IV gene and the mode for the transfer of genetic information between bacteria of farm animals and farm workers. Thirty six E. coli isolates of swine, chicken, and human origins, chosen randomly from 318 apramycin-resistant E. coli isolates of six farms in northeastern of China during 2004-2007, were multi-resistant and carried the aac(3)-IV gene encoding resistance to apramycin. Conjugation experiments demonstrated that in all 36 cases, the gene encoding resistance to apramycin was borne on a mobilisable plasmid. Homology analysis of the cloned aac(3)-IV gene with the sequence (accession no. X01385) in GenBank showed 99.3% identity at a nucleotide level, but only with a deletion of guanosine in position 813 of the gene in all 36 cases. The results indicted that resistance to apramycin in these isolates was closely related to aac(3)-IV gene. Therefore, the multi-resistance of E.coli could complicate therapeutic practices for enteric infections in both farm animals and human.
- Published
- 2009
- Full Text
- View/download PDF
50. L-cysteine supplementation attenuates local inflammation and restores gut homeostasis in a porcine model of colitis.
- Author
-
Kim CJ, Kovacs-Nolan J, Yang C, Archbold T, Fan MZ, and Mine Y
- Subjects
- Animals, Animals, Newborn, Caspase 8 genetics, Colitis chemically induced, Colon drug effects, Colon metabolism, Colon pathology, Dextran Sulfate, Dietary Supplements, Disease Models, Animal, Enzyme-Linked Immunosorbent Assay, Gastrointestinal Tract metabolism, Gastrointestinal Tract pathology, Gene Expression drug effects, Interleukin-12 Subunit p40 genetics, Interleukin-12 Subunit p40 metabolism, Interleukin-1beta genetics, Interleukin-1beta metabolism, Interleukin-6 genetics, Interleukin-6 metabolism, Intestinal Absorption drug effects, Reverse Transcriptase Polymerase Chain Reaction, Swine, Tumor Necrosis Factor-alpha genetics, Tumor Necrosis Factor-alpha metabolism, bcl-X Protein genetics, Colitis prevention & control, Cysteine administration & dosage, Gastrointestinal Tract drug effects, Homeostasis drug effects, Inflammation prevention & control
- Abstract
Background: Inflammatory bowel disease (IBD), a chronic inflammation of the gastrointestinal tract, is characterized by a deregulation of the mucosal immune system and resistance of activated T cells to apoptosis. Current therapeutics show limited efficacy and potential toxicity; therefore there is a need for novel approaches for the treatment of IBD. L-cysteine was examined for its ability to reduce colitis symptoms and modulate local gene expression in a DSS-induced porcine model of colitis., Methods: Colitis was induced via intra-gastric infusion of dextran sodium sulfate (DSS), followed by the administration of L-cysteine or saline. Clinical signs, morphological measurements, histology and gut permeability were assessed for the prognosis of colitis. Local tissue production of cytokines and gene expression in the colon were analyzed by ELISA and real-time RT-PCR., Results: L-cysteine supplementation attenuated DSS-induced weight loss and intestinal permeability, reduced local chemokine expression and neutrophil influx, and markedly improved colon histology. Furthermore, cysteine significantly reduced the expression of pro-inflammatory cytokines, including TNF-alpha, IL-6, IL-12p40, IL-1beta, and resulted in increased expression of the apoptosis initiator caspase-8 and decreased expression of the pro-survival genes cFLIP and Bcl-xL., Conclusions and General Significance: These results suggest that L-cysteine administration aids in restoring gut immune homeostasis by attenuating inflammatory responses and restoring susceptibility of activated immune cells to apoptosis, and that cysteine supplementation may be a novel therapeutic strategy for the treatment of IBD.
- Published
- 2009
- Full Text
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