Effect of feeding T-2 toxin contaminated feed on the utilisation of vitamin E in chickens

The purpose of the present study was to investigate the effect of experimental T-2 toxin load (2.35 mg/kg of feed) and vitamin E supply in the drinking water (10.5 mg/bird/day) on vitamin E levels of the blood plasma and liver in broiler chickens in a 14-day experiment. It was found that T-2 toxin load did not influence vitamin E content of the blood plasma except at day 3 after the toxin load when a moderate increase was detected in plasma vitamin E. No significant changes were found in vitamin E content of the liver. The simultaneous use of high-dose vitamin E supplementation and T-2 toxin load caused a significantly higher plasma vitamin E content but the changes were less expressed in the group subjected to T-2 toxin load. Vitamin E supply also resulted in a marked and significant increase in vitamin E concentrations of the liver on days 3 and 7 even in the T-2 loaded group, but this concentration significantly decreased thereafter. The results show that T-2 contamination of the diet has an adverse effect on the utilisation of vitamin E in broiler chickens.     

Genome-wide association study of yield components and fibre quality traits in a cotton germplasm diversity panel

A genome-wide association study (GWAS) was conducted on a diversity panel of 103 cotton accessions over three seasons to determine genetic contributions to a range of cotton yield components including fibre quality, plant architecture and stomatal conductance traits. The accessions covered breeding lines, released cultivars and some obsolete cultivars that contributed significantly to modern breeding pools. They were genotyped with Illumina’s CottonSNP63 K single nucleotide polymorphism (SNP) assay. Broad-sense heritability was low for yield component traits (\(h_{B}^{2}\) = 0.14–0.43), except for gin turnout and boll weight (\(h_{B}^{2}\)) = 0.74 and 0.59, respectively), and low to high for fibre quality traits (\(h_{B}^{2}\) = 0.26–0.89). Population structure analysis revealed extensive admixture and cryptic relatedness amongst the accessions. Genome-wide linkage disequilibrium (LD) analyses showed LD decayed, on average, within a physical distance of 5 Mbp and reduced to 2 Mbp at r ² ≥ 0.2, suggesting that few markers are necessary for association mapping in cotton. A mixed linear model accounting for population structure and cryptic relatedness identified 17 and 50 significant SNP associations for fibre length and micronaire, respectively. GWAS failed to detect significant associations in other traits, with the contribution of any single SNP to the phenotypic falling below 5%. This may be due to the low level of DNA polymorphism in cotton and/or insufficient resolution provided by the cotton SNP chip. Whole genome sequencing combined with whole genomic selection approaches that do not require prior knowledge about the effect or function of individual SNPs may be better suited than GWAS for trait dissection and prediction in cotton breeding.     

松茸SCAR标记的建立

松茸群全球共报道15个种1变种,我国记载5个种1变种(臧穆,1990).长白山区有2种,即松茸(Tricholoma matsutake)和假松茸(T.bakamatsutake),同属于口蘑属.松茸是与松属(Pinus)树木共生的一种外生菌根菌,不仅菌肉肥厚、营养丰富、风味绝佳,而且具有抗癌作用(傅伟杰等,2005).     

The local immune response of mice after Helicobacter suis infection: strain differences and distinction with Helicobacter pylori

Helicobacter (H.) suis colonizes the stomach of pigs and is the most prevalent gastric non-H. pylori Helicobacter species in humans. Limited information is available on host immune responses after infection with this agent and it is unknown if variation in virulence exists between different H. suis strains. Therefore, BALB/c and C57BL/6 mice were used to compare colonization ability and gene expression of various inflammatory cytokines, as determined by real-time PCR, after experimental infection with 9 different H. suis strains. All strains were able to persist in the stomach of mice, but the number of colonizing bacteria at 59 days post inoculation was higher in stomachs of C57BL/6 mice compared to BALB/c mice. All H. suis strains caused an upregulation of interleukin (IL)-17, which was more pronounced in BALB/c mice. This upregulation was inversely correlated with the number of colonizing bacteria. Most strains also caused an upregulation of regulatory IL-10, positively correlating with colonization in BALB/c mice. Only in C57BL/6 mice, upregulation of IL-1β was observed. Increased levels of IFN-γ mRNA were never detected, whereas most H. suis strains caused an upregulation of the Th2 signature cytokine IL-4, mainly in BALB/c mice. In conclusion, the genetic background of the murine strain has a clear impact on the colonization ability of different H. suis strains and the immune response they evoke. A predominant Th17 response was observed, accompanied by a mild Th2 response, which is different from the Th17/Th1 response evoked by H. pylori infection.     

Entangling the spatial properties of laser beams

Position and momentum were the first pair of conjugate observables explicitly used to illustrate the intricacy of quantum mechanics. We have extended position and momentum entanglement to bright optical beams. Applications in optical metrology and interferometry require the continuous measurement of laser beams, with the accuracy fundamentally limited by the uncertainty principle. Techniques based on spatial entanglement of the beams could overcome this limit, and high-quality entanglement is required. We report a value of 0.51 for inseparability and 0.62 for the Einstein-Podolsky-Rosen criterion, both normalized to a classical limit of 1. These results are a conclusive optical demonstration of macroscopic position and momentum quantum entanglement and also confirm that the resources for spatial multimode protocols are available.     

An oncogene-induced DNA damage model for cancer development

Of all types of DNA damage, DNA double-strand breaks (DSBs) pose the greatest challenge to cells. One might have, therefore, anticipated that a sizable number of DNA DSBs would be incompatible with cell proliferation. Yet recent experimental findings suggest that, in both precancerous lesions and cancers, activated oncogenes induce stalling and collapse of DNA replication forks, which in turn leads to formation of DNA DSBs. This continuous formation of DNA DSBs may contribute to the genomic instability that characterizes the vast majority of human cancers. In addition, in precancerous lesions, these DNA DSBs activate p53, which, by inducing apoptosis or senescence, raises a barrier to tumor progression. Breach of this barrier by various mechanisms, most notably by p53 mutations, that impair the DNA damage response pathway allows cancers to develop. Thus, oncogene-induced DNA damage may explain two key features of cancer: genomic instability and the high frequency of p53 mutations.     

Constitutive expression of Cry proteins in roots and border cells of transgenic cotton

Transgenic cotton plants expressing Cry1Ac and Cry2Ab, from the soil bacterium Bacillus thuringiensis (Bt), provide effective control of certain lepidopteran pests, however, little is known about the proteins below ground expression. We used ELISA to quantify in vitro expression of the Cry1Ac and Cry2Ab proteins in mucilage, root border cells and root tips in five transgenic cultivars of cotton compared to conventional cultivar Sicot 189. Expression of Cry proteins in roots and border cells of the transgenic cotton cultivars was constitutive and at detectable levels, with Cry1Ac and Cry2Ab protein expression ranging from <20 ppb to >100 pbb. To determine if genetically modified cotton demonstrated simple differences in properties of the root, when compared to an elite parental line (cv. Sicot 189), we enumerated border cells on seedling radicles. Border cell counts of 14 cultivars ranged from 0.2 to 1.1 × 10⁴ cells per root tip with an average of 5 × 10³ border cells. Border cell production in the transgenic cultivars was generally similar to that of both donor and elite parents, the exception being the cultivar Sicot 189, which had substantially more border cells than all of its transgenic derivatives. Comparison of border cell number with varietal disease resistance ranking found a limited relationship (r ² = 0.65, n = 7) between border cell numbers and the commercial resistance rank against Fusarium wilt of cotton. The implications of differences in cotton cultivar border cell number and root tip expression of Cry proteins for plant–microbe interactions in the rhizosphere and the soil ecosystem are yet to be resolved.     

Immunoglobulin G1 Fc in colostral whey.

Two IgG1 fragments were isolated from bovine colostral whey. Based on gel diffusion analysis, both fragments originated from the Fc portion of the molecule but were not identical to IgG1 Fc prepared by papain cleavage. The molecular weights were determined to be 66,000 and 14,000 daltons and it was hypothesized that the larger fragment could be a polymer of the smaller. No IgG1 Fab or IgG2 fragments could be demonstrated.