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51.
Macrophage polarization is the driving force of various inflammatory diseases, especially those involved in M1/M2 imbalance. N6-methyladenosine (m6A) is the most prevalent internal mRNA modification in eukaryotes that affects multiple biological processes, including those involved developmental arrest and immune response. However, the role of m6A in macrophage polarization remains unclear. This study found that FTO silencing significantly suppressed both M1 and M2 polarization. FTO depletion decreased the phosphorylation levels of IKKα/β, IκBα and p65 in the NF-κB signaling pathway. The expression of STAT1 was downregulated in M1-polarized macrophages while the expression of STAT6 and PPAR-γ decreased in M2 polarization after FTO knockdown. The actinomycin D experiments showed that FTO knockdown accelerated mRNA decay of STAT1 and PPAR-γ. Furthermore, the stability and expression of STAT1 and PPAR-γ mRNAs increased when the m6A reader YTHDF2 was silenced. In conclusion, our results suggest that FTO knockdown inhibits the NF-κB signaling pathway and reduces the mRNA stability of STAT1 and PPAR-γ via YTHDF2 involvement, thereby impeding macrophage activation. These findings indicated a previously unrecognized link between FTO and macrophage polarization and might open new avenues for research into the molecular mechanisms of macrophage polarization-related diseases.  相似文献   
52.
《Genomics》2020,112(2):1477-1480
Using the CaprineSNP50 data generated by the AGIN consortium, we detected common CNVs in 126 samples from four African indigenous goat breeds. A total of 30 CNVs ranging from 30,237 bp to 4,910,757 bp were identified. These CNVs were then associated with six growth traits by a linear regression analysis. Three significant associations were identified between two CNVs and two body traits after false discovery rate (FDR) correction (P < .05). One of them (CNV27) was significantly associated with both chest width and width of pin bones. It overlaps the SNX29 gene, the Gene Ontology (GO) annotations of which indicate CNV27 could be a potential functional candidate for meat production, health and reproduction traits. To our knowledge, this study is the first CNV-based association test of growth traits using SNP chip data in African meat goats.  相似文献   
53.
AmB is an antifungal drug of polyene. Although it is prone to nephrotoxicity, it is still the gold standard in the clinical treatment of fungal infection. Sterol plays a decisive role in the drug activity of AmB. The antifungal activity of AmB depends on ergosterol in fungal membranes, and its toxicity is related to cholesterol in mammalian membranes. At the same time, AmB interacts with biofilms, leading to a significant loss of potassium ions and affecting the transport of potassium ions across membranes. Meanwhile, metal cation may also affect AmB molecules’ aggregation on the membrane. This paper mainly studied the effects of different concentrations of potassium ions on the interactions between AmB and lipid monolayers containing cholesterol or ergosterol and explored the differences in the impact of varying potassium ions on the drug activity of AmB on monolayers rich in these two kinds of sterols. The results show that potassium ions caused the collapse of lipid monolayer and lipid-AmB monolayer to disappear. The limiting molecular area of these monolayers also increased due to potassium ions. The limiting molecular area of the monolayer in the presence of ergosterol has a great difference in the different concentration of potassium ions, which is different from that in the presence of cholesterol. The presence of potassium ions, regardless of the intensity of K+ ions, increased the maximum elastic modulus of the lipid/sterol monolayer with and without AmB. The presence of potassium ions reduced the influence of AmB on the stability of the lipid monolayer containing cholesterol. The impact of AmB on the stability of the lipid monolayer containing ergosterol was related to the concentration of potassium ions. The potassium ions increased the area of the ordered “island” region on the lipid-AmB monolayer containing cholesterol, and the boundary of the microregion produced different degrees of curvature. However, on the lipid/ergosterol monolayer, 5 mM and 10 mM potassium ions made the holes caused by AmB more denser, and the diameter of holes become larger. These results can help to improve the effect of potassium ions on the transmembrane transport of substances affected by AmB. The results will provide a basis for further exploration of the effect mechanism of metal ions on the antifungal activity of polyene drugs.  相似文献   
54.
55.
A droplet-vitrification protocol was described for cryopreservation of shoot tips of kiwifruit ‘Yuxiang’ (Actinidia chinensis var. deliciosa). No significant differences were found in root formation and shoot growth between the in vitro-derived shoots (the control) and cryo-derived ones when cultured in vitro. No significant differences were detected in survival and vegetative growth between the in vitro-derived plants (the control) and cryo-derived ones after re-establishment in greenhouse conditions. Inter-simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP) did not detect any polymorphic bands in the cryo-derived shoots when cultured in vitro and the cryo-derived plants after re-establishment in greenhouse conditions. These data indicate rooting ability, vegetative growth and genetic stability are maintained in the cryo-derived kiwifruit plants recovered from the droplet-vitrification cryopreservation. Methylation sensitive amplification polymorphism (MSAP) detected 12.8% and 1.6% DNA methylation in the cryo-derived shoots when cultured in vitro and the cryo-derived plants after re-established in greenhouse conditions, respectively. This droplet-vitrification was applied to five cultivars and three rootstocks belonging to A. chinensis var. deliciosa, A. chinensis var. chinensis, A. macrosperma, A. polygama and A. valvata. The highest (68.3%) and lowest (22.5%) shoot regrowth were obtained in A. macrosperma and A. chinensis var. chinensis ‘Jinmi’, respectively, with an average of 46.4% shoot regrowth obtained across the eight genotypes. The droplet-vitrification protocol described here can be considered the most applicable cryopreservation method so far reported for the genus Actinidia. Results reported here provide theoretical and technical supports for setting up cryo-banks of genetic resources of Actinidia spp.  相似文献   
56.
This study investigates the effects of cryopreservation and supplementation of buffalo's semen with Caffeic acid. It studies the effects of different Caffeic acid concentrations on cryopreservation capacity of the buffalo and evaluates their influence on various sperm parameters like motility, viability, progressive motility, sperm plasma membrane integrity, and antioxidant status. Twenty-four semen samples were collected with an artificial vaginal from three adult water buffalos. The semen samples were evaluated and the qualified ejaculates were separated and were diluted in a Tris-based extender. The resulting samples were classified into 5 groups: No antioxidant (control), Control sham (NaOH), Caffeic acid 50 μM, Caffeic acid 100 μM, and Caffeic acid 200 μM. The semen samples encountered cryodamage and the quality was deteriorating during the cryopreservation (P < 0.05). The semen evaluation after thawing showed that the groups of samples receiving 100 μM Caffeic acid had higher viability, total motility, and lower abnormal sperm and better linearity (LIN), curvilinear velocity (VCL), straight-line velocity (VSL) and path velocity and higher intact plasma membrane (P < 0.05) compared to other groups. It is notable that adding 100 μM Caffeic acid to freezing extenders enhances the CAT, GPx, SOD, and GSH and also ameliorates total antioxidant capacity of spermatozoa after thawing. It is notable that the addition of 100 μM Caffeic acid decreases the amount of Malondialdehyde. These reactions lead us to conclude that 100 μM Caffeic acid enhances the semen quality of water buffalo after thawing.  相似文献   
57.
[目的] 为研究添加饲用益生菌对肉牛生长性能、血液生理生化指标及肠道微生物区系的影响。[方法] 在青海地区选取西门塔尔牛与荷斯坦牛的杂交1代18头,按每组平均体重相近的原则随机分为2组,每组9头,试验组饮食添加地衣芽孢杆菌、枯草芽孢杆菌和酿酒酵母的复合饲用益生菌。[结果] 试验结果表明:试验组显著地提高了胸围日增长量(P=0.029);试验组皮质醇浓度显著(P<0.05)高于对照组,高密度胆固醇脂蛋白、低密度胆固醇脂蛋白与总胆固醇浓度显著(P<0.05)低于对照组;进一步分析肠道微生物发现,两组之间Alpha多样性没有显著差异(P>0.05),Beta多样性差异显著(P<0.05);TenericutesAlistipesRuminococcaceae的相对丰度在试验组显著高于对照组(P<0.05),而Alloprevotella相对丰度显著低于对照组(P<0.05);检测到的芽孢杆菌种没有显著的差异,有趣的是,试验组降低了肠道中的大肠杆菌丰度。[结论] 综上,饲喂复合饲用益生菌能够有效降低血清胆固醇的合成、抑制有害微生物的繁殖。该研究为益生菌干预肉牛健康养殖提供了理论依据。  相似文献   
58.
The cysteine and glycine-rich protein 1 and 2 genes (CSRP1 and CSRP2) are an effective growth factor in promoting skeletal muscle growth in vitro and vivo. However, in cattle, the information on the CSRP1 and CSRP2 genes is very limited. The aim of this study was to examine the association of the CSRP1 and CSRP2 variants with growth and carcass traits in cattle breeds. Three single nucleotide variants (SNVs) were identified within the bovine CSRP1 gene, whereas CSRP2 gene has not detected any SNVs, using DNA pooled sequencing, PCR-RFLP, and forced PCR-RFLP methods. These SNVs include g. 801T>C (Intron 2), g. 46T>C (Exon 3) and g. 99C>G (Intron 3). Besides, we also investigated haplotype frequencies and linkage disequilibrium (LD) coefficients for three SNVs in all study populations. LD and haplotype structure of CSRP1 were different between breeds. The result of haplotype analysis demonstrated eight haplotype present in QC (Qinchuan) and one haplotype in CH (Chinese Holstein). Only haplotype 1 (TTC), shared by all two populations, comprised 10.74% and 100.00%, of all haplotypes observed in QC and CH, respectively. Haplotype 5 (CTC) had the highest haplotype frequencies in QC (30.98%) and haplotype 1 had the highest haplotype frequencies in CH (100.00%). The statistical analyses indicated that one single SNV and 19 combined haplotypes were significantly or highly significantly associated with growth and carcass traits in the QC cattle population (P < 0.05 or P < 0.01). Quantitative real-time PCR (qRT-PCR) analyses showed that the bovine CSRP1 and CSRP2 genes were widely expressed in many tissues. The results of this study suggest that the CSRP1 gene possibly is a strong candidate gene that affects growth and carcass traits in the Chinese beef cattle breeding.  相似文献   
59.
In this study, we cloned the full coding region of NGF gene from the caprine ovary. Result showed the caprine NGF cDNA (GenBank Accession No. JQ308184) contained a 726 bp open reading frame encoding a protein with 241 amino acid residues. Bioinformatic analysis indicated that caprine NGF amino acid sequence was 83–99 % identical to that of mouse, pig, dog, human and bovine. It was predicted that caprine NGF contained nine serine phosphorylation loci, four threonine phosphorylation loci and nine specific PKC phosphorylation loci. The NGF mRNA expression pattern showed that NGF gene was expressed highly in ovary. This work provided an important experimental basis for further research on the function of NGF in goat. A single nucleotide polymorphism (A705G) in the coding region of NGF gene was detected by PCR–RFLP and DNA sequencing in 630 goats of three breeds. The frequencies of G allele were 0.52–0.61, and frequencies of A allele were 0.48–0.39 for SN, GZ and BG breeds, respectively. The does with GG genotype had higher litter size than those with GA and AA genotypes (P < 0.05). Hence, the biochemical and physiological functions, together with the results obtained in our investigation, suggest that the NGF gene could serve as a genetic marker for litter size in goat breeding.  相似文献   
60.
Y chromosome diversity and paternal origin of Chinese cattle   总被引:2,自引:0,他引:2  
To determine the Y chromosome genetic diversity and paternal origin of Chinese cattle, 369 bulls from 17 Chinese native cattle breeds and 30 bulls from Holstein and four bulls from Burma were analyzed using a recently discovered USP9Y marker that could distinguish between taurine and indicine cattle more efficiently. In total, the taurine Y1, Y2 haplogroup and indicine Y3 haplogroup were detected in 7 (1.9 %), 193 (52.3 %) and 169 (45.8 %) individuals of 17 Chinese native breeds, respectively, although these frequencies varied amongst the Chinese native cattle breeds examined. Y2 dominates in northern China (91.4 %), while Y3 dominates in southern China (81.2 %). Central China is an admixture zone with Y2 predominating overall (72.0 %). Our results demonstrate that Chinese cattle have two paternal origins, one from B. taurus (Y2) and the other from B. indicus (Y3). The Y1 haplogroup may originate from the imported beef cattle breeds in western countries. The geographical distributions of the Y2 and Y3 haplogroup frequencies reveal a pattern of male indicine introgression from south to north China, and male taurine introgression from north to south China.  相似文献   
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