Aflatoxin B1, zearalenone and deoxynivalenol in feed ingredients and complete feed from different Province in China

Background： The current study was carried out to provide a reference for monitory of aflatoxin B_1（AFB_1）,zearalenone（ZEN） and deoxynivalenol（DON） contamination in feed ingredients and complete feeds were collected from different Province in China from 2013 to 2015.Methods： A total of 443 feed ingredients, including 220 corn, 24 wheat, 24 domestic distillers dried grains with soluble（DDGS）, 55 bran, 20 wheat shorts and red dog, 37 imported DDGS, 34 corn germ meal and 29 soybean meal as well as 127 complete feeds including 25 pig complete feed（powder）, 90 pig complete feed（pellet）, six duck complete feed and six cattle complete feed were randomly collected from different Province in China,respectively, by high-performance chromatography in combined with UV or fluorescence analysis.Results： The incidence rates of AFB_1, ZEN and DON contamination of feed ingredients and complete feeds were80.8, 92.3 and 93.9 %, respectively. The percentage of positive samples for DON ranged from 66.7 to 100 %.Domestic DDGS and imported DDGS presented the most serious contamination AFB_1, ZEN and DON contamination levels of feeds ranged from 61.5 to 100 %, indicated that serious contamination over the studied 3-year period.Conclusion： The current data provide clear evidence that AFB_1, ZEN and DON contamination of feed ingredients and complete feeds in different Province in China is serious and differs over past 3-year. The use of corn, domestic DDGS, imported DDGS and corn germ meal, which may be contaminated with these three mycotoxins, as animal feed may triggered a health risk for animal. Feeds are most contaminated with DON followed by ZEN and AFB_1.Mycotoxins contamination in feed ingredients and complete feeds should be monitored routinely in China.

Gut microbiota bridges dietary nutrients and host immunity

Dietary nutrients and the gut microbiota are increasingly recognized to cross-regulate and entrain each other,and thus affect host health and immune-mediated diseases.Here,we systematically review the current understanding linking dietary nutrients to gut microbiota-host immune interactions,emphasizing how this axis might influence host immunity in health and diseases.Of relevance,we highlight that the implications of gut microbiota-targeted dietary intervention could be harnessed in orchestrating a spectrum of immune-associated diseases.

High-peak-power random Yb-fiber laser with intracavity Raman-frequency comb generation

The random fiber laser(RFL)has been an excellent platform for exploring novel optical dynamics and developing new functional optoelectronic devices.However,it is challenging for RFLs to regulate their emission into regular narrow pulses due to their intrinsic randomness.Here,through engineering the laser configuration(cavity Q value,gain distribution and nonlinearity),we demonstrate that narrow(~2.5 ns)pulses with record peak power as high as 64.3 kW are achieved from a self-Q-switched random ytterbium fiber laser.Based on high intracavity intensity and efficient interplay of multiple nonlinear processes(stimulated Brillouin scattering,stimulated Raman scattering and four-wave mixing),an over-one-octave visible-near-infrared(NIR)Raman-frequency comb is generated from single-mode silica fibers for the first time.After spectrally filtering the Raman peaks,wavelength-tunable pulses with durations of several hundreds of picoseconds are obtained.Such a high-peak-power random Q-switched fiber laser and wide frequency comb in the visible-NIR region can find applications in diverse areas,such as spectroscopy,biomedical imaging and quantum information.

Role of iron in host-microbiota interaction and its effects on intestinal mucosal growth and immune plasticity in a piglet model

Iron is an essential trace element for both the host and resident microbes in the gut. In this study, iron was administered orally and parenterally to anemic piglets to investigate the role of iron in host-microbiota interaction and its effects on intestinal mucosal growth and immune plasticity. We found that oral iron administration easily increased the abundance of Proteobacteria and Escherichia-Shigella, and decreased the abundance of Lactobacillus in the ileum. Furthermore, similar bacterial changes, namely an increase in Proteobacteria, Escherichia-Shigella, and Fusobacterium and a reduction in the Christensenellaceae_R-7_group,were observed in the colon of both iron-supplemented groups. Spearman's correlation analysis indicated that the changed Fusobacterium, Fusobacteria and Proteobacteria in the colon were positively correlated with hemoglobin, colon and spleen iron levels. Nevertheless, it was found that activated m TOR1 signaling, improved villous height and crypt depth in the ileum,enhanced immune communication, and increased protein expression of IL-22 and IL-10 in the colon of both iron-supplemented groups. In conclusion, the benefits of improved host iron outweigh the risks of altered gut microbiota for intestinal mucosal growth and immune regulation in treating iron deficiency anemia.

Effects of combined chemical design(Cu addition) and topographical modification(SLA) of Ti-Cu/SLA for promoting osteogenic, angiogenic and antibacterial activities

Cu has been proved to possess various beneficial biological activities, while sandblasting and acid etching(SLA) is widely used to modify the commercial dental implant in order to improve osseointegration. Based on the above, a novel antimicrobial dental implant material, Ti-Cu alloy, was treated with SLA, to combine chemical design(Cu addition) and topographical modification(SLA). In this work, the effects of SLA treated Ti-Cu alloys(Ti-Cu/SLA) on osteogenesis, angiogenesis and antibacterial properties were evaluated from both in vitro and in vivo tests, and Ti/SLA and Ti-Cu(without SLA) were served as control groups. Benefiting by the combined effects of chemical design(Cu addition) and micro-submicron hybrid structures(SLA),Ti-Cu/SLA had significantly improved inhibitory effects on oral anaerobic bacteria(P. gingivalis and S.mutans) and could induce upregulation of osteogenic-related and angiogenic-related genes expression in vitro. More importantly, in vivo studies also demonstrated that Ti-Cu/SLA implants had wonderful biological performance. In the osseointegration model, Ti-Cu/SLA implant promoted osseointegration via increasing peri-implant bone formation and presenting good bone-binding, compared to Ti/SLA and Ti-Cu implants. Additionally, in the peri-implantitis model, Ti-Cu/SLA effectively resisted the bone resorption resulted from bacterial infection and meanwhile promoted osseointegration. All these results suggest that the novel multiple functional Ti-Cu/SLA implant with rapid osseointegration and bone resorption inhibition abilities has the potential application in the future dental implantation.

Development and applications of gain-switched fiber lasers[Invited]

We briefly review the development of gain-switched rare-earth-doped fiber lasers and their applications in wavelength conversion to mid-IR,supercontinuum generation,and medicine in recent years.We illustrate the similarities between gain-switching and Q-switching techniques that will provide tools for the design and optimization of the gain-switched fiber lasers.From the nature of the gain-switched fiber lasers,benefits of this kind of lasers to 2-μm region and in-band-pumped(two-level system)laser systems are obvious.Advantages of in-band-pumped 2-μm lasers are discussed and analyzed with a simple numerical simulation in terms of Tm-doped fiber lasers.We also propose the key factors in the development of the gain-switched fiber lasers and predict the future tendency.

Extraction and identification of the chyme proteins in the digestive tract of growing pigs

This study aimed to explore the rule of degradation of dietary proteins by identifying chyme proteins in different segments of the digestive tract of growing pigs, using proteomics techniques. Six growing pigs were fed a corn-soybean meal-based diet for 7 days. The feedstuff and chyme proteins were separately extracted and separated with SDS-PAGE. 2 D LCMS/MS combined with protein database searching identified 1,513 proteins in different segments of the gastrointestinal tract, the number of identified exogenous proteins gradually decline from the stomach to colon, with large amounts in the duodenum to the large intestine.More corn proteins than soybean proteins were identified both in the feedstuff and chyme, and these were significantly decreased after digestion in the stomach. More membrane proteins than non-membrane proteins were identified in whole digestive tract.These results regarding the profiles of chyme proteins in different segments of the gastrointestinal tract would provide useful information for optimizing feed formula in pigs.

Anti-infection mechanism of a novel dental implant made of titanium-copper(TiCu)alloy and its mechanism associated with oral microbiology

This work was focused on study of anti-infection ability and its underlying mechanism of a novel dental implant made of titanium-copper(TiCu)alloy.In general,most studies on antibacterial implants have used a single pathogen to test their anti-infection ability using infectious animal models.However,dental implant-associated infections are polymicrobial diseases.We innovatively combine the classic ligature model in dogs with sucrose-rich diets to induce oral infections via the canine native oral bacteria.The anti-infection ability,biocompatibility and underlying mechanism of TiCu implant were systematically investigated in comparison with pure Ti implant via general inspection,hematology,imageology(micro-CT),microbiology(16S rDNA and metagenome),histology,and Cu ion detections.Compared with Ti implant,TiCu implant demonstrated remarkable anti-infection potentials with excellent biocompatibility.Additionally,the underlying anti-infection mechanism of TiCu implant was considered to involve maintaining the oral microbiota homeostasis.It was found that the carbohydrates in the plaques formed on the surface of TiCu implant were metabolized through the tricarboxylic acid cycle(TCA)cycles,which prevented the formation of an acidic microenvironment and inhibited the accumulation of acidogens and pathogens,thereby maintaining the microflora balance between aerobic and anaerobic bacteria.

Dietary zero-dimensional fullerene supplementation improves the meat quality,lipid metabolism,muscle fiber characteristics,and antioxidative status in finishing pigs

With the increasing demand for high-quality pork,more nutritional substances have been studied for the regulation of meat quality.Zero-dimensional fullerenes(C60)can modulate the biological behavior of a variety of cell lines and animals.In this study,we report the biological effects of C60 on finishing pigs at different concentrations.A total of 24 barrows(Duroc×Large White×Landrace),with an average body weight of 21.01±0.98 kg,were divided into 3 groups and each treated daily with C60(100 or 200 mg per kg feed)or a control diet until the end of the experiment.Our results showed that dietary C60 supplementation improved flesh color,marbling scores,and flavor amino acid contents of longissimus dorsi(LD)of growing-finishing pigs(P<0.05).C60 improved meat quality by regulating lipid metabolism and muscle fiber morphology by mediating the expression of genes,L-lactic dehydrogenase(LDH),myosin heavy chain(MyHC)IIa,MyHCIIb,peroxisome proliferator-activated receptor γ(PPARγ),and fatty acid transport protein 1(FATP1)(P<0.05).Moreover,C60 substantially promoted the mRNA expression of antioxidant enzyme genes(P<0.05),which also contributed to improving meat quality.These findings have important implications for the application of C60 in the livestock industry,especially for improving the meat quality of fattening pigs.