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1.
bioRxiv ; 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37502998

RESUMO

The recent discovery by cryo-electron microscopy that the neuropatho-logical hallmarks of different tauopathies, including Alzheimer's disease, corticobasal degeneration (CBD), and progressive supranuclear palsy (PSP), are caused by unique misfolded conformations of the protein tau is among the most profound developments in neurodegenerative disease research. To capitalize on these discoveries for therapeutic development, one must achieve in vitro replication of tau fibrils that adopt the rep-resentative tauopathy disease folds - a grand challenge. To understand whether the commonly used, but imperfect, fragment of the tau pro-tein, K18, is capable of inducing specific protein folds, fibril seeds derived from CBD- and PSP-infected biosensor cells expressing K18, were used to achieve cell-free assembly of naïve, recombinant 4R tau into fibrils without the addition of any cofactors. Using Double Electron Electron Resonance (DEER) spectroscopy, we discovered that cell-passaged patho-logical seeds generate heterogeneous fibrils that are distinct between the CBD and PSP lysate-seeded fibrils, and are also unique from heparin-induced tau fibril populations. Moreover, the lysate-seeded fibrils contain a characteristic sub-population that resembles either the CBD or PSP disease fold, corresponding with the respective starting patient sam-ple. These findings indicate that CBD and PSP patient-derived fibrils retain strain properties after passaging through K18 reporter cells.

2.
J Phys Chem B ; 126(34): 6384-6395, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35994024

RESUMO

The aggregation of the tau protein is central to several neurodegenerative diseases, collectively known as tauopathies. High-resolution views of tau tangles accumulated under pathological conditions in post-mortem brains have been revealed recently by cryogenic electron microscopy. One of the striking discoveries was that fibril folds are unique to and homogeneous within one disease family, but typically different between different tauopathies. It is widely believed that seeded aggregation can achieve structural propagation of tau fibrils and generate pathological fibril structures. However, direct molecular level measurement of structural evolution during aggregation is missing. Here, we discuss our perspective on the biophysical approaches that can contribute to the ongoing debate regarding the prion-like propagation of tau and the role of cofactors. We discuss the unique potential of double electron-electron resonance (DEER)-based intramolecular distance measurement, sensitive to two to several nanometers distances. DEER can track the structural evolution of tau along the course of aggregation from the completely disordered state, to partially ordered and highly ordered fibril states, and has the potential to be a key tool to elucidate the disease-specific tau aggregation pathways.


Assuntos
Doença de Alzheimer , Príons , Tauopatias , Doença de Alzheimer/metabolismo , Encéfalo , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Tauopatias/metabolismo , Tauopatias/patologia , Proteínas tau/química
3.
Eur J Histochem ; 65(4)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34852453

RESUMO

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a kind of diffuse inflammatory injury caused by various factors, characterized by respiratory distress and progressive hypoxemia. It is a common clinical critical illness. The aim of this study was to investigate the effect and mechanism of the Mucin1 (MUC1) gene and its recombinant protein on lipopolysaccharide (LPS)-induced ALI/ARDS. We cultured human alveolar epithelial cell line (BEAS-2B) and used MUC1 overexpression lentivirus to detect the effect of MUC1 gene on BEAS-2B cells. In addition, we used LPS to induce ALI/ARDS in C57/BL6 mice and use hematoxylin and eosin (H&E) staining to verify the effect of their modeling. Recombinant MUC1 protein was injected subcutaneously into mice. We examined the effect of MUC1 on ALI/ARDS in mice by detecting the expression of inflammatory factors and oxidative stress molecules in mouse lung tissue, bronchoalveolar lavage fluid (BALF) and serum. Overexpression of MUC1 effectively ameliorated LPS-induced damage to BEAS-2B cells. Results of H&E staining indicate that LPS successfully induced ALI/ARDS in mice and MUC1 attenuated lung injury. MUC1 also reduced the expression of inflammatory factors (IL-1ß, TNF-α, IL-6 and IL-8) and oxidative stress levels in mice. In addition, LPS results in an increase in the activity of the TLR4/NF-κB signaling pathway in mice, whereas MUC1 decreased the expression of the TLR4/NF-κB signaling pathway. MUC1 inhibited the activity of TLR4/NF-κB signaling pathway and reduced the level of inflammation and oxidative stress in lung tissue of ALI mice.


Assuntos
Lesão Pulmonar Aguda , Mucina-1/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Linhagem Celular , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Proteínas Recombinantes/farmacologia
4.
Sci Rep ; 11(1): 16753, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408214

RESUMO

Geo-materials may present varying mechanical properties under different stress paths, especially for tunnel excavation, which is typically characterized by the decreased radial stress and increased axial stress during the complex loading and unloading process. This study carried out a comparative analysis between the loading and unloading model testing, which was then combined with PFC2D simulation, aiming to reveal the fracture propagation pattern, microscopic stress and force chain distribution of the rock mass surrounding the tunnel. Comparisons of extents and development of tensile strain between loading and unloading testing results were made. The overall stability, the integrity of rock mass, and the failure pattern transition under loading and unloading processes were systematically examined. In addition, for the two unloading cases with different vertical stresses imposed, the failure patterns were both identified as the collapse of the V - shaped extruded sidewall, due to the coupling of the shear failure and the vertical tensile failure in the sidewall wedge.

5.
Transl Anim Sci ; 5(2): txab029, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34386710

RESUMO

A meta-analysis was conducted to determine the effects of the dietary energy system (net energy or metabolizable energy), oil content of corn distillers dried grains with solubles (cDDGS), diet inclusion levels, and pig age on growth performance of pigs fed cDDGS-based diets. Mean differences of average daily gain (ADG), average daily feed intake (ADFI), and gain:feed (G:F) were calculated and expressed as a percentage change relative to feeding corn-soybean meal (SBM)- and cDDGS-based diets to nursery [body weight (BW) < 25 kg] and growing-finishing (BW > 25 kg) pigs, and to compare the effects of supplementing various types of exogenous enzymes without or with phytase on growth performance. A total of 27 studies with 106 growth performance observations were included in the cDDGS dataset, and 34 studies with 84 observations for enzyme responses in cDDGS diets were used in the enzyme dataset. Approximately, 64.7% of the observations showed no change, and 26.7% of observations showed a reduction in ADG, ADFI, and G:F when feeding cDDGS-based diets to the nursery and growing-finishing pigs compared with feeding corn-SBM-based diets. Furthermore, feeding cDDGS diets resulted in decreased (P < 0.01) mean difference of ADG (-4.27%) and G:F (-1.99%) for nursery pigs, and decreased (P < 0.01) mean difference of ADG (-1.68%) and G:F (-1.06%) for growing-finishing pigs. Every percentage unit increase in the inclusion level of cDDGS in growing-finishing pig diet was associated with a decrease (P < 0.01) in ADG (-0.10%) and ADFI (-0.09%). Feeding high oil (≥10% ether extract) cDDGS-based diets to pigs resulted in a 2.96% reduction in ADFI whereas feeding reduced-oil (<10% ether extract) cDDGS-based diets reduced G:F by 1.56% compared with pigs fed corn-SBM-based diets. Supplementation of exogenous enzymes improved (P < 0.05) the mean difference of ADG and G:F by 1.94% and 2.65%, respectively, in corn-SBM-based diets, and by 2.67% and 1.87%, respectively, in cDDGS diets. Supplementation of exogenous protease, enzyme cocktail, or xylanase improved (P < 0.05) ADG by 7.29%, 2.64%, and 2.48% in pigs fed corn-SBM-based diets, respectively. There were no differences between the dietary addition of single enzymes and enzyme combinations for any growth performance parameters in corn-SBM- or cDDGS-based diets. In conclusion, feeding cDDGS-based diets slightly reduces the growth performance of nursery and growing-finishing pigs, but supplementation of xylanase or enzyme cocktail can improve G:F of pigs fed cDDGS-based diets.

6.
J Anim Sci Biotechnol ; 11: 50, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32426132

RESUMO

[This corrects the article DOI: 10.1186/s40104-015-0004-5.].

7.
ACS Chem Neurosci ; 11(4): 615-627, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31971365

RESUMO

Amyloid aggregation of the microtubule binding protein tau is a hallmark of many neurodegenerative diseases. Recently, tau has been found to undergo liquid-liquid phase separation (LLPS) by an electrostatically driven complex coacervation (CC) mechanism near physiological conditions. Although LLPS and aggregation have been shown to simultaneously occur under certain common conditions, it is unclear whether LLPS promotes aggregation of tau, or whether they are two independent processes. In this study, we address this question by combining multiple biochemical and biophysical assays in vitro. We investigate the impacts of LLPS-CC on cofactor-induced tau aggregation by evaluating the conformation of tau, kinetics of aggregation, and fibril quantity. We showed that none of these properties are influenced directly by LLPS-CC and that LLPS-CC and cofactor-induced aggregation of tau merely occur under overlapping conditions of enhanced intermolecular interactions and localization but are two independent processes. We furthermore showed that tau LLPS can be driven by nonelectrostatic interaction using high-salt concentrations. Under these conditions, LLPS strongly correlated with increased aggregation propensity. Whether LLPS of tau formed under different conditions or of different constituents may actively promote aggregation of tau remains an open question, but this study shows that the readily accessible electrostatically driven condensation of tau into LLPS in and of itself is not sufficient to promote aggregation.


Assuntos
Amiloide/metabolismo , Amiloidose/metabolismo , Agregação Patológica de Proteínas/metabolismo , Proteínas tau/metabolismo , Proteínas Amiloidogênicas/metabolismo , Humanos , Microtúbulos/metabolismo , Doenças Neurodegenerativas/metabolismo
8.
Animals (Basel) ; 9(10)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600978

RESUMO

An experiment was conducted to investigate the effect of inoculum volume (IV), substrate quantity, and the use of a manual or automated gas production (GP) recording system for in vitro determinations of fermentation of corn distillers dried grains with solubles (cDDGS) and soybean hulls (SBH). A 2 × 2 × 2 factorial arrangement of treatments was used and included the factors of (1) ingredients (cDDGS or SBH), (2) inoculum volume and substrate quantity (IV30 = 0.2 g substrate + 30 mL inoculum or IV75 = 0.5 g substrate + 75 mL inoculum), and (3) GP recording system (MRS = manual recording system or ARS = automated recording system). Feed ingredient samples were pre-treated with pepsin and pancreatin, and the hydrolyzed residues were subsequently incubated with fresh pig feces in a buffered mineral solution. The GP recording was monitored for 72 h, and the kinetics were estimated by fitting data using an exponential model. Compared with SBH, cDDGS yielded less (p < 0.01) maximal gas production (Gf), required more time (p < 0.02) to achieve half gas accumulation (T/2), and had less (p < 0.01) fractional rate of degradation (µ) and in vitro fermentability of dry matter (IVDMF). Using the ARS resulted in less IVDMF (p < 0.01) compared with MRS (79.0% vs. 81.2%, respectively). Interactions were observed between GP recording system and inoculum volume and substrate quantity for Gf (p < 0.04), µ (p < 0.01), and T/2 (p < 0.04) which implies that increasing inoculum volume and substrate quantity resulted in decreased Gf (332 mL/g from IV30 vs. 256 mL/g from IV75), µ (0.05 from IV30 vs. 0.04 from IV75), and T/2 (34 h for IV30 vs. 25 h for IV75) when recorded with ARS but not MRS. However, the recorded cumulative GP at 72 h was not influenced by the inoculum volume nor recording system. The precision of Gf (as measured by the coefficient of variation of Gf) tended to increase for IV30 compared with IV75 (p < 0.10), indicating that using larger inoculum volume and substrate quantity (IV75) reduced within batch variation in GP kinetics. Consequently, both systems showed comparable results in GP kinetics, but considering convenience and achievement of consistency, 75 mL of inoculum volume with 0.5 g substrate is recommended for ARS.

9.
J Anim Sci ; 97(8): 3460-3471, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31260527

RESUMO

Characterizing fiber into fermentable and unfermentable fractions may enhance the accuracy of estimating DE and ME energy content in fiber-rich ingredients. Therefore, the objective of this study was to analyze the concentrations of NDF, representing both the fermentable (fNDFom) and unfermentable (uNDFom) portions among sources of corn distillers dried grains with solubles (DDGS), and determine their relative contributions to DE and ME content. The concentrations of DE and ME, as well as apparent total tract digestibility (ATTD) of GE, were measured in a previous experiment. Samples of DDGS (0.5 g) were mixed with fecal inoculum and incubated for 8, 12, and 72 h. The ash corrected NDF (NDFom) content of DDGS residues at each time point was determined. The fNDFom increased with fermentation time of 8 h (21.6%), 12 h (29.0%), and 72 h (68.6%). The ATTD of GE increased as the uNDFom decreased at 8 h (uNDFom8; R2 = 0.83; P < 0.01) and 72 h (uNDFom72; R2 = 0.83; P < 0.01). Likewise, ME content of DDGS increased as uNDFom72 decreased (R2 = 0.59; P < 0.01). The best-fit DE equation was DE (kcal/kg DM) = 2,175 - 3.07 × uNDFom8 (g/kg, DM) - 1.50 × uNDFom72 (g/kg, DM) + 0.55 × GE (kcal/kg DM) (R2 = 0.94, SE = 36.21). The best-fit ME equation was ME (kcal/kg DM) = 1,643 - 2.31 × uNDFom8 (g/kg, DM) - 2.54 × uNDFom72 (g/kg, DM) + 0.65 × GE (kcal/kg DM) - 1.42 × crude protein (g/kg DM) (R2 = 0.94, SE = 39.21). These results indicate that in vitro unfermented fiber is negatively associated with GE and NDF digestibility, and therefore, is a good predictor of DE and ME content in corn-DDGS.


Assuntos
Ração Animal/análise , Fibras na Dieta/metabolismo , Metabolismo Energético , Suínos/metabolismo , Animais , Dieta/veterinária , Digestão , Grão Comestível , Fezes/química , Fermentação , Trato Gastrointestinal/metabolismo , Zea mays/química
10.
J Anim Sci ; 97(8): 3313-3325, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31257437

RESUMO

As a result of genetic selection for increased litter size, modern, highly prolific sows often produce large litters with an increased percentage of light birth weight (BiW) piglets compared with less prolific females. However, there is limited information elucidating what proportion of light BiW piglets that express compensatory growth and how these pigs might be identified at a young age. The objective of this study was to analyze the effect of birth weight and early phase growth on preweaning mortality, subsequent growth performance, and carcass characteristics of pigs. Individual records collected on 7,654 commercial crossbred pigs were used for analyses. A segmented regression model was used to analyze the effect of birth weight on preweaning survival and a series of mixed models were used to analyze the effect of birth weight (n = 7,654) group on weights recorded at: weaning (n = 6,777), nursery exit (n = 4,805), and finishing exit (n = 1,417); hot carcass weight (HCW), and lean percentage (n = 4,572). The effect of growth rate group was defined during suckling (< 225 or ≥ 225 g/d) or the nursery phase (< 424 or ≥ 424 g/d). Preweaning mortality, growth rate, BW, and carcass traits were adjusted to a standard age, and ADG and lean percentage were calculated. Results of segmented regression analysis showed that the slope of preweaning mortality on birth weights below 0.99 kg differed (P < 0.05) from the slope of preweaning mortality regressed on birth weights above 0.99 kg. The mixed model analyses showed a positive linear effect (P < 0.05) of BiW and quadratic effect (P < 0.05) of sow parity on age-adjusted finishing weight (FiW), HCW, and lean percentage. The positive influences of increasing BiW were greater (P < 0.05) in age-adjusted FiW and HCW for pigs with slow suckling growth rate compared with those with fast suckling growth rate. Pigs with fast nursery growth rate had greater (P < 0.05) age-adjusted FiW and HCW compared with the slow growing nursery contemporaries. In conclusion, piglets born weighing less than 1 kg were at a higher risk of preweaning mortality than piglets born weighing 1 kg or greater. Light BiW pigs, but not heavy BiW pigs, may lose compensatory growth capability if growth rate during the suckling phase is below the average level.


Assuntos
Suínos/fisiologia , Animais , Peso ao Nascer , Feminino , Tamanho da Ninhada de Vivíparos , Masculino , Paridade , Gravidez , Taxa de Sobrevida , Suínos/crescimento & desenvolvimento , Desmame , Aumento de Peso
11.
World J Microbiol Biotechnol ; 35(4): 66, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30941513

RESUMO

It is widely assumed that bacterial resistance will be acquired when bacteria are exposed to long-term sublethal concentrations of antibiotics. The objective of this study was to evaluate the ability of two bacterial strains [Lactobacillus plantarum (18A) and Lactobacillus paracasei (18C)] isolated from the fuel ethanol industry to acquire bacterial resistance during long-term (≥ 14 days) exposure to sublethal concentrations of penicillin G and virginiamycin. Neither strain acquired resistance to virginiamycin after 69 days of exposure, but both strains did acquire resistance to penicillin G after 18 days. Strain 18A appeared to acquire resistance to a penicillin G and virginiamycin mixture after 7 days of exposure, but the incubation period was not long enough to verify. These results indicate that antibiotic resistance in two common Lactobacillus strains does not develop from sublethal exposure to virginiamycin after 69 days of exposure, but resistance can be developed with sublethal exposure to penicillin G.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Etanol/metabolismo , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Biocombustíveis , Fermentação , Lacticaseibacillus paracasei/efeitos dos fármacos , Lacticaseibacillus paracasei/crescimento & desenvolvimento , Lacticaseibacillus paracasei/isolamento & purificação , Lacticaseibacillus paracasei/metabolismo , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , Testes de Sensibilidade Microbiana , Modelos Teóricos , Penicilina G/farmacologia , Virginiamicina/farmacologia
12.
Proc Natl Acad Sci U S A ; 115(52): 13234-13239, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30538196

RESUMO

Amyloid fibrils are cross-ß-rich aggregates that are exceptionally stable forms of protein assembly. Accumulation of tau amyloid fibrils is involved in many neurodegenerative diseases, including Alzheimer's disease (AD). Heparin-induced aggregates have been widely used and assumed to be a good tau amyloid fibril model for most biophysical studies. Here we show that mature fibrils made of 4R tau variants, prepared with heparin or RNA, spontaneously depolymerize and release monomers when their cofactors are removed. We demonstrate that the cross-ß-sheet assembly formed in vitro with polyanion addition is unstable at room temperature. We furthermore demonstrate high seeding capacity with transgenic AD mouse brain-extracted tau fibrils in vitro that, however, is exhausted after one generation, while supplementation with RNA cofactors resulted in sustained seeding over multiple generations. We suggest that tau fibrils formed in brains are supported by unknown cofactors and inhere higher-quality packing, as reflected in a more distinct conformational arrangement in the mouse fibril-seeded, compared with heparin-induced, tau fibrils. Our study suggests that the role of cofactors in tauopathies is a worthy focus of future studies, as they may be viable targets for diagnosis and therapeutics.


Assuntos
Doença de Alzheimer/patologia , Amiloide/química , Encéfalo/patologia , Heparina/química , RNA/química , Proteínas Recombinantes/química , Proteínas tau/química , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Heparina/metabolismo , Camundongos , Camundongos Transgênicos , Conformação Proteica , RNA/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas tau/metabolismo
13.
PLoS One ; 13(11): e0207196, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30408134

RESUMO

Due to their complex chemical and physical properties, the effects and mechanisms of action of natural sources of dietary fiber on the intestine are unclear. Pigs are commonly fed high-fiber diets to reduce production costs and non-starch polysaccharide (NSP)-degrading enzymes have been used to increase fiber digestibility. We evaluated the expression of mucin 2 (MUC2), presence of goblet cells, and ileal immune profile of pigs housed individually for 28 days and fed either a low fiber diet based on corn-soybean meal (CSB, n = 9), or two high fiber diets formulated adding 40% corn distillers' dried grains with solubles (DDGS, n = 9) or 30% wheat middlings (WM, n = 9) to CSB-based diet. Pigs were also fed those diets supplemented with a NSP enzymes mix (E) of xylanase, ß-glucanase, mannanase, and galactosidase (n = 8, 10, and 9 for CSB+E, DDGS+E and WM+E, respectively). Feeding DDGS and WM diets increased ileal MUC2 expression compared with CSB diet, and this effect was reversed by the addition of enzymes. There were no differences in abundance of goblet cells among treatments. In general, enzyme supplementation increased gene expression and concentrations of IL-1ß, and reduced the concentrations of IL-4, IL-17A and IL-11. The effects of diet-induced cytokines on modulating intestinal MUC2 were assessed in vitro by treating mouse and swine enteroids with 1 ng/ml of IL-4 and IL-1ß. In accordance with previous studies, treatment with Il-4 induced Muc2 and expansion of goblet cells in mouse enteroids. However, swine enteroids did not change MUC2 expression or number of goblet cells when treated with IL-4 or IL-1ß. Our results suggest that mucin and immune profile are regulated by diet in the swine intestine, but by mechanisms different to mouse, emphasizing the need for using appropriate models to study responses to dietary fiber in swine.


Assuntos
Fibras na Dieta/administração & dosagem , Glicosídeo Hidrolases/administração & dosagem , Glicosídeo Hidrolases/metabolismo , Íleo/imunologia , Íleo/metabolismo , Mucina-2/metabolismo , Polissacarídeos/metabolismo , Ração Animal/análise , Animais , Citocinas/administração & dosagem , Citocinas/metabolismo , Fibras na Dieta/análise , Suplementos Nutricionais , Grão Comestível , Feminino , Expressão Gênica , Células Caliciformes/citologia , Células Caliciformes/metabolismo , Íleo/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mucina-2/genética , Glycine max , Sus scrofa , Triticum , Zea mays
14.
Materials (Basel) ; 10(2)2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28772566

RESUMO

Broadband nonlinear optical properties from 500 to 1550 nm of ultrasmall black phosphorus quantum dots (BPQDs) have been extensively investigated by using the open-aperture Z-scan technique. Our results show that BPQDs exhibit significant nonlinear absorption in the visible range, but saturable absorption in the near-infrared range under femtosecond excitation. The calculated nonlinear absorption coefficients were found to be (7.49 ± 0.23) × 10-3, (1.68 ± 0.078) × 10-3 and (0.81 ± 0.03) × 10-3 cm/GW for 500, 700 and 900 nm, respectively. Femtosecond pump-probe measurements performed on BPQDs revealed that two-photon absorption is responsible for the observed nonlinear absorption. The saturable absorption behaviors observed at 1050, 1350 and 1550 nm are due to ground-state bleaching induced by photo-excitation. Our results suggest that BPQDs have great potential in applications as broadband optical limiters in the visible range or saturable absorbers in the near-infrared range for ultrafast laser pulses. These ultrasmall BPQDs are potentially useful as broadband optical elements in ultrafast photonics devices.

15.
Anim Sci J ; 88(6): 873-881, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27753186

RESUMO

Reactive oxygen species (ROS) have been shown to have a role in inflammation. We investigated whether Forsythia suspensa extract (FSE) could exert its antioxidant potential against lipopolysaccharide (LPS)-induced inflammatory liver injury in rats. Rats were orally fed FSE once daily for 7 consecutive days prior to LPS (Escherichia coli, serotype O55:B5) injection. LPS treatment caused liver dysfunction as evidenced by massive histopathological changes and increased serum alanine aminotransferase and aspartate aminotransferase activities which were ameliorated by FSE pretreatment. FSE attenuated LPS-induced depletion of cytosolic nuclear factor-erythroid 2-related factor 2 (Nrf2) and suppression of Nrf2 nuclear translocation in liver, and the generation of ROS and malondialdehyde in serum and liver. FSE increased the Nrf2-mediated induction of heme oxygenase-1 in liver, as well as superoxide dismutase and glutathione peroxidase activities in serum and liver. Importantly, FSE attenuated LPS-induced nuclear factor-кB (NF-кB) nuclear translocation in liver, and subsequently decreased tumor necrosis factor-α, interleukin (IL)-1ß and IL-6 levels in serum and liver, which were associated with FSE-induced activation of Nrf2 in liver. These results indicate that the protective mechanisms of FSE may be involved in the attenuation of oxidative stress and the inhibition of the NF-кB-mediated inflammatory response by modulating the Nrf2-mediated antioxidant response against LPS-induced inflammatory liver injury.


Assuntos
Antioxidantes/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Forsythia/química , Lipopolissacarídeos/efeitos adversos , Fator de Transcrição NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Heme Oxigenase-1/metabolismo , Fígado/metabolismo , Malondialdeído/metabolismo , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
16.
Anim Sci J ; 88(8): 1082-1092, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27921350

RESUMO

To determine the effects of standardized ileal digestible (SID) valine : lysine ratio on the performance, milk composition and plasma indices of lactating sows, 32 Large White × Landrace sows (219.78 ± 7.15 kg body weight; parity 1.82 ± 0.62) were allotted to one of four dietary treatments with eight sows per treatment based on parity, back fat thickness and body weight. The sows were fed corn-soybean meal-based diets containing 63, 83, 103 or 123% SID valine : lysine from day 107 of gestation until day 28 of lactation. The average daily feed intake of sows and daily weight gain of piglets increased linearly (P < 0.05) while back fat loss decreased linearly (P < 0.05) as the SID valine : lysine ratio increased. All of the analyzed amino acids in sow colostrum and valine concentrations of sow and piglet plasma increased linearly (P < 0.05) with the increasing SID valine : lysine ratio. In conclusion, 88 and 113% dietary SID valine : lysine ratios were optimal to achieve minimum back fat loss and maximum piglet growth rate using a linear-break point model which exceeds the requirement of 85% that is estimated by the National Research Council (2012).


Assuntos
Ração Animal/análise , Dieta/veterinária , Lactação/fisiologia , Lisina/análise , Leite/química , Suínos/crescimento & desenvolvimento , Suínos/fisiologia , Valina/análise , Animais , Colostro/química , Ingestão de Alimentos , Feminino , Suínos/sangue , Aumento de Peso
17.
Anim Sci J ; 88(6): 854-862, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27758020

RESUMO

We investigated the effects of Forsythia suspensa extract (FSE) and chito-oligosaccharide (COS), alone or together, on performance and health status of weaned piglets. The treatments included a basal diet and three diets with 160 mg/kg COS, 100 mg/kg FSE, or 100 mg/kg FSE and 160 mg/kg COS. Supplementation with COS or FSE alone improved (P < 0.01) average daily gain and feed conversion ratio compared with the basal diet in the first 2 weeks. On day 14, COS or FSE supplementation separately produced stronger (P < 0.01) serum total antioxidant capacity and glutathione peroxidase activities and lower serum endotoxin (P < 0.05) and malondialdehyde (P < 0.01) concentrations, generated higher (P < 0.01) serum complement 4 concentration, peripheral blood lymphocyte proliferation and serum-specific ovalbumin antibody level than the basal diet. No differences in oxidative injury and immunity indices were detected on day 28. The combined FSE and COS produced similar results compared with FSE or COS when given alone. These data indicate FSE or COS can increase performance by modulating intestinal permeability, antioxidant status and immune function in younger pigs. There appears to be similar advantage in feeding the additives in combination over those obtained from feeding them separately.


Assuntos
Antioxidantes/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Forsythia/química , Intestinos/fisiologia , Oligossacarídeos/administração & dosagem , Extratos Vegetais/administração & dosagem , Suínos/crescimento & desenvolvimento , Suínos/imunologia , Ração Animal , Animais , Feminino , Masculino , Suínos/fisiologia , Desmame
18.
Anim Sci J ; 86(8): 772-81, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25827306

RESUMO

We evaluated the apparent (AID) and standardized ileal digestibility (SID) of amino acids (AA) in spray-dried egg (SPE) and albumen powder (AP) compared with spray-dried porcine plasma (SDPP), dried porcine solubles (DPS) and fish meal (FM). Additionally, the effects of these egg byproducts as a replacement for conventional animal proteins on the performance and nutrient digestibility of piglets were studied. In Exp. 1, six barrows fitted with ileal T-cannulas were allotted to a 6 × 6 Latin Square design and fed six diets. The AID and SID of AA were generally higher in AP and FM (P < 0.01) than in the other protein sources. In Exp. 2, 150 piglets weaned at 21 days, were fed diets containing the five protein sources for 3 weeks. Weight gain of piglets fed SDPP was the highest among the treatments. Dry matter and protein digestibility for pigs offered SDPP were higher (P < 0.01) than those offered FM and DPS. AP decreased (P < 0.05) Escherichia coli counts in the cecum. DPS decreased (P < 0.05) serum diamine oxidase compared with SPE. In conclusion, AP and SPE are competitive with traditional animal protein sources and can be successfully fed to piglets without compromising performance.


Assuntos
Albuminas/administração & dosagem , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Proteínas Alimentares/administração & dosagem , Digestão , Ovos , Suínos/fisiologia , Amina Oxidase (contendo Cobre)/sangue , Aminoácidos/administração & dosagem , Animais , Carga Bacteriana , Ceco/microbiologia , Escherichia coli , Produtos Pesqueiros , Manipulação de Alimentos , Masculino , Plasma , Pós , Suínos/crescimento & desenvolvimento
19.
Biol Trace Elem Res ; 168(1): 103-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25860427

RESUMO

This study was conducted to evaluate the efficacy of a novel Buttiauxella phytase to pigs fed P-deficient, corn-soybean meal diets. One hundred and twenty crossbred piglets (9.53 ± 0.84 kg) were allocated to one of five treatments which consisted of four low P diets (0.61 % Ca and 0.46 % total P) supplemented with 0, 500, 1,000, or 20,000 FTU/kg phytase as well as a positive control diet (0.77 % Ca and 0.62 % total P). Each treatment had six replicated pens with four pigs per pen. Pigs were fed the experimental diets for 28 days. Phytase supplementation linearly improved (P < 0.05) average daily gain (ADG), feed conversion ratio (FCR), and apparent total tract digestibility (ATTD) of dry matter, gross energy, crude protein, Ca, and P in weaned pigs. Super high dosing with phytase (20,000 FTU/kg) further increased (P < 0.05) ADG compared with 500 FTU/kg phytase inclusion group, as well as ATTD of Ca and P. Metacarpal bone characteristics and several trace mineral concentration in bone, plasma, or organ tissues were linearly (P < 0.05) improved at increasing dose of phytase. Super high dosing with phytase (20,000 FTU/kg) supplementation improved (P < 0.05) Mn and Zn concentration in bone compared to normal dose of phytase supplementation (500 or 1,000 FTU/kg). In conclusion, supplementation of 500 FTU of Buttiauxella phytase/kg and above effectively hydrolyzed phytate in a low-P corn-soybean diet for pigs. In addition, a super high dosing with phytase (20,000 FTU/kg) improved macro- or micro mineral availability and growth performance.


Assuntos
6-Fitase/farmacologia , Digestão/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Crescimento/efeitos dos fármacos , Minerais/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Densidade Óssea , Desenvolvimento Ósseo/efeitos dos fármacos , Suplementos Nutricionais , Estado Nutricional/efeitos dos fármacos , Fósforo/deficiência , Glycine max , Sus scrofa , Suínos , Zea mays
20.
Anim Sci J ; 86(3): 279-85, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25302651

RESUMO

A total of 144 weaned piglets were used to evaluate the effects of essential oil (EO) supplementation of a low-energy diet on performance, apparent nutrient digestibility, small intestinal morphology, intestinal microflora, immune properties and antioxidant activities in weaned pigs. Pigs received a low-energy diet (negative control, NC, digestible energy = 3250 kcal/kg), NC plus 0.025% EO or a positive control diet (PC, digestible energy = 3400 kcal/kg) for 28 days. Growth performance was similar between the EO group and PC group. However, EO supplementation increased (P < 0.05) average daily gain and the apparent digestibility of dry matter, crude protein and energy compared with pigs fed the NC diet. Greater (P < 0.05) villus height and lower (P < 0.05) counts of Escherichia coli and total anaerobes in the rectum in the EO group were observed compared with NC or PC groups. Pigs fed EO diet had higher (P < 0.05) concentrations of albumin, immunoglobulin A (IgA), IgG and total antioxidant capacity and lower fecal score than pigs fed the PC and NC diets. Above all, this study indicates that supplementation of EO to a low-energy pig diet has beneficial results and obtains similar performance compared with normal energy (PC) diet.


Assuntos
Ração Animal , Antioxidantes/metabolismo , Restrição Calórica , Suplementos Nutricionais , Mucosa Intestinal , Intestinos , Óleos Voláteis/administração & dosagem , Suínos/crescimento & desenvolvimento , Suínos/fisiologia , Albuminas/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bactérias Anaeróbias , Carga Bacteriana , Proteínas Alimentares/metabolismo , Digestão/fisiologia , Metabolismo Energético , Escherichia coli , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/anatomia & histologia , Intestinos/imunologia , Intestinos/microbiologia , Desmame
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