14 research outputs found

    Observations on the Hybrid F of Trachypthecus leucocephalus and T. francioisi and Its Offspring

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    The characteristics and behaviours of F1f (the female hybrid of Trachypithecus leucocephalus and T. francoisi) and its backcross offspring (Be1, Be2, Be3 and Be4) were extensively observed. The results showed that the hybrid F1f and its offspring had similar characteristics with T. francoisi. Besides the black hair was an overwhelmingly dominant character, the changing of their hair colour, the breeding behaviour of hybridized F1,and the growing process and behaviours of the hybrid F1f offspring resembled T. francoisi. However the feature of T. leucocephalus was nearly not present in the hybrid F1 and its offspring, excepting that in the development process the time for their hair colour change was longer and during their growth there existed imprinting phenomenon of T. leucocephalus. Therefore it can be inferred that the gene control of T. leucocephalus only played a supporting role and T. francoisi's gene dominated in the hybrid F1f and their offspring. The percent of weak infants for backcross langurs reaching 50%, which was higher than that of the general 10%-20% of T. francoisi, suggested a sign of outbreeding depression. Based on our observation that the hybrid F1f was able to reproduce its offspring successfully we can make a conclusion that T. leucocephalus should be considered as a subspecies of T. francoisi instead of an independent species

    Synthesis and performance of a novel amphoteric polycarboxylate superplasticizer with hydrolysable ester group

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    A novel hydrolysable cationic monomer of quaternary ammonium dialkyl maleate was synthesized and subsequently copolymerized with acrylic acid and isobutenyl polyethylene glycol to successfully yield an amphoteric polycarboxylate superplasticizer (APC). The effects of the APC on cement particles were systematically investigated. The fluidity, fluidity retention and mechanical properties were measured to evaluate the performances of the APC and compared with those of a polycarboxylate superplasticizer (PCE). In addition, X-ray diffraction, thermogravimetric and scanning electron microscopy characterization were performed to investigate the influences of the APC on cement particles from microscopic level. Furthermore, the interactions of the APC with cement particles were also investigated via adsorption, hydration heat and zeta potential measurements. It was found that the introduction of a hydrolysable cationic monomer could improve the micro-structure and delay the hydration of cement. Moreover, the APC could increase the cement paste fluidity and fluidity retention

    Synthesis and properties of a novel amphoteric polycarboxylate superplasticizer

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    The synthesis, characterization and properties of novel amphoteric polycarboxylate superplasticizers (PCs) are highlighted in this work. Specifically, two classes of amphoteric PCs were prepared through the addition of isobutenyl polyethylene glycol, acrylic acid and synthesized amphoteric monomer. The fluidity and fluidity retention of cement pastes containing these PCs and their adsorption behavior were investigated. In addition the cement hydration heat was measured, while X-ray diffraction and thermogravimetric behavior were also characterized. Consequently, the results indicated that these amphoteric PCs exhibited good dispersion performance and enhanced adsorption onto the cement. Furthermore, the results revealed that the PCs exerted a retardation effect during the early stages of cement hydration and subsequently accelerated this process, without affecting the subsequent cement hydration. These findings highlight the potential applications of these amphoteric PCs in concrete engineering. [GRAPHICS]

    Highly Soluble Phenylethynyl-terminated Imide Oligomers and Thermosetting Polyimides Based on 2,2 ',3,3 '-Biphenyltetracarboxylic Dianhydride

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    Highly Soluble Phenylethynyl-terminated Imide Oligomers and Thermosetting Polyimides Based on 2,2 ',3,3 '-Biphenyltetracarboxylic Dianhydrid

    MicroRNA-27a-3p Inhibits Melanogenesis in Mouse Skin Melanocytes by Targeting Wnt3a

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    MicroRNAs (miRNAs) play an essential role in the regulation of almost all the biological processes, including melanogenesis. MiR-27a-3p is nearly six times higher in white alpaca skin compared to brown skin, which indicates that miR-27a-3p may be a candidate regulator for melanogenesis. Wnt3a plays an important role in promoting melanoblasts to differentiate into melanocytes and melanogenesis. To confirm the function of miR-27a-3p to melanogenesis in mammals, miR-27a-3p mimic, inhibitor and their negative control were transfected into mouse melanocytes. As a result, miR-27a-3p inhibits melanogenesis by repressing Wnt3a at post-transcriptional level. A significant decrease in Wnt3a luciferase activity was observed in 293T cells co-transfected with the matched luciferase reporter vector and pre-miR-27a. Furthermore, the presence of exogenous miR-27a-3p significantly decreased Wnt3a protein expression rather than mRNA and reduced β-catenin mRNA levels in melanocytes. The over-expression of miR-27a-3p significantly increased the melanin content of melanocytes. However, miR-27a-3p inhibitor performs an opposite effect on melanogenesis. Wnt3a is one target of miR-27a-3p. MiR-27a-3p could inhibit Wnt3a protein amount by post-transcriptional regulation and melanogenesis in mouse melanocytes. Previous studies reported that Wnt3a promoted melanogenensis in mouse melanocytes. Thus, miR-27-3p inhibits melanogenesis by repressing Wnt3a protein expression

    MicroRNA-27a-3p Inhibits Melanogenesis in Mouse Skin Melanocytes by Targeting Wnt3a

    Get PDF
    MicroRNAs (miRNAs) play an essential role in the regulation of almost all the biological processes, including melanogenesis. MiR-27a-3p is nearly six times higher in white alpaca skin compared to brown skin, which indicates that miR-27a-3p may be a candidate regulator for melanogenesis. Wnt3a plays an important role in promoting melanoblasts to differentiate into melanocytes and melanogenesis. To confirm the function of miR-27a-3p to melanogenesis in mammals, miR-27a-3p mimic, inhibitor and their negative control were transfected into mouse melanocytes. As a result, miR-27a-3p inhibits melanogenesis by repressing Wnt3a at post-transcriptional level. A significant decrease in Wnt3a luciferase activity was observed in 293T cells co-transfected with the matched luciferase reporter vector and pre-miR-27a. Furthermore, the presence of exogenous miR-27a-3p significantly decreased Wnt3a protein expression rather than mRNA and reduced β-catenin mRNA levels in melanocytes. The over-expression of miR-27a-3p significantly increased the melanin content of melanocytes. However, miR-27a-3p inhibitor performs an opposite effect on melanogenesis. Wnt3a is one target of miR-27a-3p. MiR-27a-3p could inhibit Wnt3a protein amount by post-transcriptional regulation and melanogenesis in mouse melanocytes. Previous studies reported that Wnt3a promoted melanogenensis in mouse melanocytes. Thus, miR-27-3p inhibits melanogenesis by repressing Wnt3a protein expression

    Identification and characterization of microRNAs in white and brown alpaca skin

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    BACKGROUND: MicroRNAs (miRNAs) are small, non-coding 21–25 nt RNA molecules that play an important role in regulating gene expression. Little is known about the expression profiles and functions of miRNAs in skin and their role in pigmentation. Alpacas have more than 22 natural coat colors, more than any other fiber producing species. To better understand the role of miRNAs in control of coat color we performed a comprehensive analysis of miRNA expression profiles in skin of white versus brown alpacas. RESULTS: Two small RNA libraries from white alpaca (WA) and brown alpaca (BA) skin were sequenced with the aid of Illumina sequencing technology. 272 and 267 conserved miRNAs were obtained from the WA and BA skin libraries, respectively. Of these conserved miRNAs, 35 and 13 were more abundant in WA and BA skin, respectively. The targets of these miRNAs were predicted and grouped based on Gene Ontology and KEGG pathway analysis. Many predicted target genes for these miRNAs are involved in the melanogenesis pathway controlling pigmentation. In addition to the conserved miRNAs, we also obtained 22 potentially novel miRNAs from the WA and BA skin libraries. CONCLUSION: This study represents the first comprehensive survey of miRNAs expressed in skin of animals of different coat colors by deep sequencing analysis. We discovered a collection of miRNAs that are differentially expressed in WA and BA skin. The results suggest important potential functions of miRNAs in coat color regulation

    Identification and characterization of microRNAs in white and brown alpaca skin

    No full text
    Abstract Background MicroRNAs (miRNAs) are small, non-coding 21–25 nt RNA molecules that play an important role in regulating gene expression. Little is known about the expression profiles and functions of miRNAs in skin and their role in pigmentation. Alpacas have more than 22 natural coat colors, more than any other fiber producing species. To better understand the role of miRNAs in control of coat color we performed a comprehensive analysis of miRNA expression profiles in skin of white versus brown alpacas. Results Two small RNA libraries from white alpaca (WA) and brown alpaca (BA) skin were sequenced with the aid of Illumina sequencing technology. 272 and 267 conserved miRNAs were obtained from the WA and BA skin libraries, respectively. Of these conserved miRNAs, 35 and 13 were more abundant in WA and BA skin, respectively. The targets of these miRNAs were predicted and grouped based on Gene Ontology and KEGG pathway analysis. Many predicted target genes for these miRNAs are involved in the melanogenesis pathway controlling pigmentation. In addition to the conserved miRNAs, we also obtained 22 potentially novel miRNAs from the WA and BA skin libraries. Conclusion This study represents the first comprehensive survey of miRNAs expressed in skin of animals of different coat colors by deep sequencing analysis. We discovered a collection of miRNAs that are differentially expressed in WA and BA skin. The results suggest important potential functions of miRNAs in coat color regulation.</p
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