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The nutrition condition of earlier life has a long-term influence on health of its later period. In order to the explore effects of in ovo feeding of vitamin C on splenic development, splenic metabolism and apoptosis were detected in embryo, adult chickens and in vitro. A total of 360 fertile eggs were selected and randomly assigned to 2 treatments: the control group (CON) and vitamin C group (VC) were injected with saline and vitamin C on embryonic day 11, respectively. Functional enrichment of differentially expressed genes by transcriptome on embryonic day 19 suggested that purine nucleotide metabolism might be a potential pathway for the in ovo feeding of vitamin C to regulate spleen development. Additionally, the in ovo feeding of vitamin C significantly increased splenic vitamin C content on post-hatch day 21. Meanwhile, the splenic expression of adenosine deaminase, serine/threonine kinase 1 and proliferating cell nuclear antigen were down-regulated, whereas the expression of cysteinyl aspartate specific proteinase 9 was up-regulated in VC group. On post-hatch day 42, the in ovo feeding of vitamin C significantly down-regulated the splenic expression of B-cell lymphoma 2, and increased the mRNA level of cysteinyl aspartate specific proteinase 9. The in ovo feeding of vitamin C could regulate the expression of genes related to adenylate metabolism and increased the apoptosis rate in vitro, which consistent with the result in vivo. Together, these results illustrated that the in ovo feeding of vitamin C regulated splenic development and maturation by affecting purine nucleotide metabolism pathway and promoting apoptosis.
This study aimed to evaluate the effect of in ovo feeding (IOF) of vitamin C at embryonic age 11 (E11) on post-hatch performance, immune status and DNA methylation-related gene expression in broiler chickens. A total of 240 Arbor Acres breeder eggs (63 (sem 0·5) g) were randomly divided into two groups: normal saline and vitamin C (VC) groups. After incubation, newly hatched chicks from each group were randomly divided into six replicates with ten chicks per replicate. Hatchability, average daily feed intake (D21–42 and D1–42), and average daily gain and feed conversion ratio (D1–21) were improved by vitamin C treatment (P < 0·05). IOF of vitamin C increased vitamin C content (D1), total antioxidant capacity (D42), IgA (D1), IgM (D1 and D21), stimulation index for T lymphocyte (D35) and lysozyme activity (D21) in plasma (P < 0·05). On D21, vitamin C increased the splenic expression of IL-4 and DNMT1 and decreased IL-1β, Tet2, Tet3 and Gadd45β expression (P < 0·05). On D42, vitamin C increased the splenic expression of IL-4 and DNMT3A and decreased IFN-γ, Tet3, MBD4 and TDG expression (P < 0·05). In conclusion, the vitamin C via in ovo injection can be absorbed by broiler’s embryo and IOF of vitamin C at E11 improves the post-hatch performance and immune status and, to some extent, the antioxidant capacity of broiler chickens. The expression of enzyme-related DNA methylation and demethylation indicates that the level of DNA methylation may increase in spleen in the VC group and whether the fluctuating expression of pro- and anti-inflammatory cytokines is related to DNA methylation change remained to be further investigated.
Limited studies have investigated the effects of serum carotenoids on the risk of non-Hodgkin lymphoma (NHL), and the findings have been inconclusive. This study aims to assess the association between serum total or specific carotenoid levels and NHL risk. This 1:1 matched, hospital-based case–control study enrolled 512 newly diagnosed (within 1 month) NHL patients and 512 healthy controls who were matched by age (±5 years) and sex in Urumqi, China. Serum carotenoid levels were measured by HPLC. Conditional logistic regression showed that higher serum total carotenoid levels and their subtypes (e.g. α-carotene, β-carotene, β-cryptoxanthin and lycopene) were dose-dependently associated with decreased NHL risk. The multivariable-adjusted OR and their 95 % CI for NHL risk for quartile 4 (v. quartile 1) were 0·31 (95 % CI 0·22, 0·48; Pfor trend < 0·001) for total carotenoids, 0·52 (95 % CI 0·33, 0·79; Pfor trend: 0·003) for α-carotene, 0·63 (95 % CI 0·42, 0·94; Pfor trend: 0·031) for β-carotene, 0·73 (95 % CI 0·49, 1·05; Pfor trend: 0·034) for β-cryptoxanthin and 0·51 (95 % CI 0·34, 0·75; Pfor trend: 0·001) for lycopene. A null association was observed between serum lutein + zeaxanthin and NHL risk (OR 0·89, 95 % CI 0·57, 1·38; Pfor trend: 0·556). Significant interactions were observed after stratifying according to smoking status, and inverse associations were more evident among current smokers than past or never smokers for total carotenoids, α-carotene and lycopene (Pfor heterogeneity: 0·047, 0·042 and 0·046). This study indicates that higher serum carotenoid levels might be inversely associated with NHL risk, especially among current smokers.
This study investigated age differences in false memory for visual scenes and the effect of immediate recall on subsequent recognition. Eighty children (7–9 years), 74 adolescents (14–16 years), 92 young adults (19–26 years) and 82 older adults (50–80 years) studied four visual scenes and then took a recognition test after either a free-recall task or a filler task. Results showed an age-related decline in false recognition for visual scenes, but this trend was eliminated when participants were asked to free-recall before recognition. Prior recall decreased false recognition in children, but increased false recognition in older adults. Across the lifespan, adolescents had the loosest criterion, children had the lowest false recall, and prior recall increased true recognition in older adults.
The effect of maternal folate intake on small-for-gestational-age (SGA) births remains inconclusive. The present study aimed to investigate the associations of maternal folate intake from diet and supplements with the risk of SGA births using data from a cross-sectional study in Shaanxi Province of Northwest China. A total of 7307 women who were within 12 months (median 3; 10th–90th percentile 0–7) after delivery were included. Two-level models were adopted to examine the associations of folate (dietary folate, supplemental folic acid and total folate) intake with the risk of SGA births and birth weight Z score, controlling for a minimum set of confounders that were identified in a directed acyclic graph. Results showed that a higher supplemental folic acid intake during the first trimester was negatively associated with the risk of SGA births (≤60 d v. non-use: OR 0·80; 95 % CI 0·66, 0·96; >60 d v. non-use: OR 0·78; 95 % CI 0·65, 0·94; Ptrend = 0·010; per 10-d increase: OR 0·97; 95 % CI 0·95, 0·99). A higher total folate intake during pregnancy was associated with a reduced risk of SGA births (highest tertile v. lowest tertile: OR 0·77; 95 % CI 0·64, 0·94; Ptrend = 0·010; per one-unit increase in the log-transformed value: OR 0·81; 95 % CI 0·69, 0·95). A similar pattern was observed for the birth weight Z score. Our study suggested that folic acid supplementation during the first trimester and a higher total folate intake during pregnancy were associated with a reduced risk of SGA births.
TRIM28/KAP1/TIF1β was identified as a universal transcriptional co-repressor and is critical for regulating post-fertilization methylation reprogramming in preimplantation embryos. In this study, three siRNAs (si647, si742, and si1153) were designed to target the TRIM28 mRNA sequence. After transfection of the mixture of the three siRNA (siMix) into bovine fibroblast cells, the most effective one for TRIM28 knockdown was selected. By injecting RNAi directed against TRIM28 mRNA, we found that TRIM28 knockdown in oocytes had the most effect on the H19 gene, in which differentially methylated region (DMR) methylation was almost completely absent at the 2-cell stage (1.4%), while control embryos showed 74% methylation. In addition, global H3K9me3 levels at the 2-cell stage were significantly higher in the in vitro fertilization (IVF) group than in the TRIM28 knockdown group (P<0.05). We further show that TRIM28 is highly expressed during oocyte maturation and reaches peak levels at the 2-cell stage. In contrast, at this stage, TRIM28 expression in somatic cell nuclear transfer (SCNT) embryos decreased significantly (P<0.05), suggesting that Trim28 transcripts are lost during SCNT. TRIM28 is required for the maintenance of methylation imprints in bovine preimplantation embryos, and the loss of TRIM28 during SCNT may contribute to the unfaithful maintenance of imprints in cloned embryos.
Identifying the relative importance of urban and non-urban land-use types for potential denitrification derived N2O at a regional scale is critical for quantifying the impacts of human activities on nitrous oxide (N2O) emission under changing environments. In this study we used a regional dataset from China including 197 soil samples and six land-use types to evaluate the main predictors (land use, heavy metals, soil pH, soil moisture, substrate availability, functional and broad microbial abundances) of potential denitrification using multivariate and pathway analysis. Our results provide empirical evidence that soils on farms have the greatest potential denitrifying ability (PDA) (10.92±6.08ng N2O-N·g–1 dry soil·min–1) followed by urban soil (6.80±5.35ng N2O-N·g–1 dry soil·min–1). Our models indicate that land use (low vs. high human activity), followed by total nitrogen (TN) and heavy metals (Cu, Zn, Pb, Cd) was the most important driver of PDA. In addition, our path analysis suggests that at least part of the impacts of land use on potential denitrification were mediated via microbial abundance, soil pH and substrates including TN, dissolved organic carbon and nitrate. This study identifies the main predictors of denitrification at a regional scale which is needed to quantify the impact of human activities on ecosystem functionality under changing conditions.
A new plasmonic photocatalyst Ag/Bi7Ta3O18 was fabricated by photodeposition-hydrothermal method. The phase composition, microstructure, surface areas, average pore size, UV-vis diffuse reflection spectra, and photocatalytic activities of composite photocatalysts were investigated in detail. The results of the measurements indicated that the Ag0 nanoparticle successfully loads on the surface of Bi7Ta3O18, and the 0.06 Ag/Bi7Ta3O18 photocatalysts exhibited the best photocatalytic activity for the degradation of Rhodamine B (RhB). The improved photocatalytic activity could be contributed to the localized surface plasmon resonance caused by the collective oscillation of the surface electrons of Ag nanoparticles. Additionally, the photocatalytic reaction mechanism was studied by photoluminescence photocurrent, and electron spin resonance analysis. As a result, the Ag nanoparticles onto the Bi7Ta3O18 surface enlarged the electron–hole separation, and the (˙OH) was the dominated active species of degradation RhB in the photocatalytic process.
Babesiosis is an emerging tick-transmitted zoonosis prevalent in large parts of the world. This study was designed to determine the rates of Babesia microti infection among small rodents in Yunnan province, where human cases of babesiosis have been reported. Currently, distribution of Babesia in its endemic regions is largely unknown. In this study, we cataloged 1672 small wild rodents, comprising 4 orders, from nine areas in western Yunnan province between 2009 and 2011. Babesia microti DNA was detected by polymerase chain reaction in 4·3% (72/1672) of the rodents analyzed. The most frequently infected rodent species included Apodemus chevrieri and Niviventer fulvescens. Rodents from forests and shrublands had significantly higher Babesia infection rates. Genetic comparisons revealed that Babesia was most similar to the Kobe- and Otsu-type strains identified in Japan. A variety of rodent species might be involved in the enzootic maintenance and transmission of B. microti, supporting the need for further serological investigations in humans.
A 100-J-level Nd:glass laser system in nanosecond-scale pulse width has been constructed to perform as a standard source of high-fluence-laser science experiments. The laser system, operating with typical pulse durations of 3–5 ns and beam diameter 60 mm, employs a sequence of successive rod amplifiers to achieve 100-J-level energy at 1053 nm at 3 ns. The frequency conversion can provide energy of 50-J level at 351 nm. In addition to the high stability of the energy output, the most valuable of the laser system is the high spatiotemporal beam quality of the output, which contains the uniform square pulse waveform, the uniform flat-top spatial fluence distribution and the uniform flat-top wavefront.
In order to achieve reliable structural characterization by transmission electron microscopy, beam-induced structural changes should be clarified for any target material system. As an example, the movement of heavy adatoms on a thin carbon support has been repeatedly reported under the electron beam while the underlying reason for such motion is still in debate. By applying statistical analysis to the group behavior of gold adatoms, we investigated their motion under different beam conditions and detected features corresponding to beam-induced motion, under typical scanning transmission electron microscopy observation conditions. Our results are consistent with the theoretical prediction proposed by Egerton (2013).
While a broad line of the Fe Kα emission is commonly found in the X-ray spectra of typical Seyfert galaxies, the situation is unclear in the case of Narrow Line Seyfert 1 galaxies (NLS1s)—an extreme subset which are generally thought to harbor less massive black holes with higher accretion rates. We report results of our study of the assemble property of the Fe K line in NLS1s by stacking the X-ray spectra of a large sample of 51 NLS1s observed with XMM-Newton. We find in the stacked X-ray spectra a prominent, broad emission feature over 4–7 keV, which is characteristic of the broad Fe Kα line. Our results suggest that a relativistic broad Fe line may in fact be common in NLS1s. The line profile is used to study the average spin of the black holes in the sample. We find, for the first time, that their black holes are constrained to be likely spinning at averagely low or moderate rates as a population. The implications of the results are discussed in the context of the black hole growth in NLS1 galaxies.
Calcification in cardiovascular aortic atherosclerotic plaque contains Ca-phosphate minerals. However, most research on cardiovascular calcification has focused on its physiological properties rather than its mineralogical features. In this present study, cardiovascular calcification was characterized by collecting samples from patients’ tissues and applying mineralogical techniques. Synchrotron radiation-based micro-X-ray diffraction showed the calcification had a similar structure to hydroxylapatite (HAp). Transmission electron microscopy showed some structurally HAp-like spherical particles with a diameter of ∼200 nm and acicular crystals ∼100 nm × ∼20 nm in size. Selected-area electron diffraction indicated that these mineral particles belonged to the hexagonal crystal system. Fourier-transform infrared (FTIR) spectroscopy showed three typical peaks at 1469 cm−1, 1455 cm−1 and 1413 cm−1, indicating that the carbonate group in the calcification plaque substituted for a hydroxyl group to form B-type CHAp (Ca10(PO4,CO3)x(OH)y). The FTIR mapping results illustrated the intergrowth of calcification and organic tissues and the inhomogeneous substitution of phosphate by carbonate in the calcification area. X-ray absorption near-edge structure analysis affirmed that the chemical environments of Ca in the calcification were close to those in HAp. Based on these mineralogical characteristics, the calcification in plaque is identified as a mixture phase of HAp and B-type carbonate HAp, which is similar to the composition of bones.
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.
Round spermatid injection (ROSI) into mammalian oocytes can result in the development of viable embryos and offspring. One current limitation to this technique is the identification of suitable round spermatids. In the current paper, round spermatids were selected from testicular cells with phase contrast microscopy (PCM) and fluorescence-activated cell sorting (FACS), and ROSI was performed in two strains of mice. The rates of fertilization, embryonic development and offspring achieved were the same in all strains. Significantly, round spermatids selected by PCM and FACS were effectively used to rescue the infertile Pten-null mouse. The current results indicate that FACS selection of round spermatids can not only provide high-purity and viable round spermatids for use in ROSI, but also has no harmful effects on the developmental capacity of subsequently fertilized embryos. It was concluded that round spermatids selected by FACS are useful for mouse strain rederivation and rescue of infertile males; ROSI should be considered as a powerful addition to the armamentarium of assisted reproduction techniques applicable in the mouse.
The unique properties of carbon nanotubes (CNTs), such as high strength and stiffness, extremely large specific surface area, low density and high electrical and thermal conductivities, open up opportunities for a wide range of applications. This has led to widespread research on the synthesis of multiscale CNT-based polymeric composites transferring the properties from nanoscale to macroscale. Currently known conventional methods for producing CNT composites rely on dispersing short nanotubes in polymer matrices or infiltrating CNT “buckypaper” with resins. Unlike conventional methods, in this work, super-aligned long CNTs were directly drawn from the vertically aligned CNT arrays and assembled into high volume fraction (~60 vol%) composites. These critical structural features allowed the CNT composites to reach tensile strengths over 1.8 GPa and electrical conductivity ~700-800 S/cm. Thermoplastic and thermosetting polymers were utilized for the fabrication and the results were compared. Our observation suggests that the strengthening and conducting mechanism is derived from the synergistic effect of high degree of CNT alignment, long CNT length, high volume fraction and uniform distribution of CNTs in the polymer matrix produced by spray-winding.
Current antidepressants are clinically effective only after several weeks of administration. We show that Fuzi polysaccharide-1 (FPS), a new water-soluble polysaccharide isolated from Fuzi, which has been used to treat mood disorders in traditional Chinese medicine for centuries, increases the number of newborn cells in the dentate gyrus in adult mice, and most of these cells subsequently differentiate into new neurons. We also found that FPS administration reduces immobility in the forced swim test, and latency in the novelty suppressed-feeding test. Moreover, a 14-d regimen with FPS reverses avoidance behaviour and inhibition of hippocampal neurogenesis induced by chronic defeat stress. In contrast, imipramine, a well known antidepressant, reverses this avoidance behaviour only after 4 wk of continuous administration. Finally, acute treatment with FPS had no effect on brain monoamine levels in frontal cortex but significantly increases BDNF in the hippocampus, while the antidepressant effect and enhancement of cell proliferation induced by FPS administration were totally blocked by K252a, an inhibitor of trkB in a chronic social defeat depression model, suggesting that the neurogenic and antidepressant effects of FPS may involve BDNF signalling. In conclusion, our findings suggest that FPS could be developed as a putative antidepressant with a rapid onset of action.