35 research outputs found

    Research on concentration and distribution of cadmium in crabs sold in Wenzhou

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    Objective To investigate the contamination and distribution of cadmium (Cd) in crabs sold in Wenzhou, and instruct consumers to eat healthily. Methods Three crab species were collected from 51 markets in 6 counties and districts of Wenzhou. The content of Cd was determined by inductively coupled plasma mass spectrometry based on GB 5009.268-2016. Results The detection rate of Cd was 100% in 235 samples. The Cd pollution in Portunus crab increase during 2013, 2015 to 2017. The Cd content of muscle and hepatopancreas in Portunus crab and Scylla serrata was higher than that in Eriocheir sinensis Milne-Edwards (P0.05). The distribution of Cd in Portunus crab was hepatopancreas and gonad> pectoral muscle > leg muscle, there was no significant difference of cadmium content in different parts between female and male crabs (P>0.05). Conclusion Cd was mainly concentrated in hepatopancreas, which was irrelevant to crab species, sex and individual difference. Cd content of Portunus crab and Scylla serrata exceeded the standard seriously, especially in hepatopancreas. People should pay more attention to the Cd pollution of crabs, and reduce the intake of hepatopancreas if necessary

    Comprehensive characterization of ERV-K (HML-8) in the chimpanzee genome revealed less genomic activity than humans

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    Endogenous retroviruses (ERVs) originate from ancestral germline infections caused by exogenous retroviruses. Throughout evolution, they have become fixed within the genome of the animals into which they were integrated. As ERV elements coevolve with the host, they are normally epigenetically silenced and can become upregulated in a series of physiological and pathological processes. Generally, a detailed ERV profile in the host genome is critical for understanding the evolutionary history and functional performance of the host genome. We previously characterized and cataloged all the ERV-K subtype HML-8 loci in the human genome; however, this has not been done for the chimpanzee, the nearest living relative of humans. In this study, we aimed to catalog and characterize the integration of HML-8 in the chimpanzee genome and compare it with the integration of HML-8 in the human genome. We analyzed the integration of HML-8 and found that HML-8 pervasively invaded the chimpanzee genome. A total of 76 proviral elements were characterized on 23/24 chromosomes, including detailed elements distribution, structure, phylogeny, integration time, and their potential to regulate adjacent genes. The incomplete structure of HML-8 proviral LTRs will undoubtedly affect their activity. Moreover, the results indicated that HML-8 integration occurred before the divergence between humans and chimpanzees. Furthermore, chimpanzees include more HML-8 proviral elements (76 vs. 40) and fewer solo long terminal repeats (LTR) (0 vs. 5) than humans. These results suggested that chimpanzee genome activity is less than the human genome and that humans may have a better ability to shape and screen integrated proviral elements. Our work is informative in both an evolutionary and a functional context for ERVs

    Identification of differentially expressed HERV-K(HML-2) loci in colorectal cancer

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    Colorectal cancer is one of the malignant tumors with the highest mortality rate in the world. Survival rates vary significantly among patients at various stages of the disease. A biomarker capable of early diagnosis is required to facilitate the early detection and treatment of colorectal cancer. Human endogenous retroviruses (HERVs) are abnormally expressed in various diseases, including cancer, and have been involved in cancer development. Real-time quantitative PCR was used to detect the transcript levels of HERV-K(HML-2) gag, pol, and env in colorectal cancer to systematically investigate the connection between HERV-K(HML-2) and colorectal cancer. The results showed that HERV-K(HML-2) transcript expression was significantly higher than healthy controls and was consistent at the population and cell levels. We also used next-generation sequencing to identify and characterize HERV-K(HML-2) loci that were differentially expressed between colorectal cancer patients and healthy individuals. The analysis revealed that these loci were concentrated in immune response signaling pathways, implying that HERV-K impacts the tumor-associated immune response. Our results indicated that HERV-K might serve as a screening tumor marker and a target for tumor immunotherapy in colorectal cancer

    论EFL写作教学中社会文化认知

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    社会文化认知影响着学生英语写作水平。社会认知理论揭示了EFL写作教学中社会文化认知的基本原理,并提出了社会学习的有效方法。学生的社会文化认知和他(她)的写作进程具有内在一致性,因而在写作教学中应注重培养学生对英语国家社会文化的认知。在英语写作教学中,教师可以通过引导阅读、转变教学方式、创设教学情境等措施来促进学生的社会文化认知,进而提高学生写作能力

    J. Alloy. Compd.

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    Gallium-bearing magnetite particles were synthesized by aerial oxidation of alkaline suspension containing both ferrous and gallium ions. It was found that the mixing procedure and temperature were critical in the preparation of ferrite particles without the formation of alpha-FeOOH (ferric oxyhydroxide), non-spherical particles and amorphous phase, evidenced by characterization of SEM and XRD. On the other band, the concentration of Ga3+ entry into the structure of spinel was different with the mixing procedure and temperature. Single phase of spinel gallium-bearing magnetites were precipitated at the temperature from 25 to 90 degrees C in the C procedure in which the neutralization of Ga was performed firstly, but the concentration of Ga entry into spinel of magnetites decreased with the temperature increasing. While in the procedure D in which neutralization of Fe ions was performed firstly, single phase of spinel gallium-bearing magnetites were precipitated only at the temperature above 65 degrees C, and the content of gallium precipitated into the magnetites increased with the temperature. Mossbauer analysis and magnetic characteristic were used to investigate the cation distribution of the gallium bearing ferrites with different ratio of Ga3+/Fe2+, which showed small content gallium introduction to have entered the tetrahedral sites preferentially rather than the octahedral sites, and increasing gallium introduction to have located between octahedral and tetrahedral sites. (c) 2007 Elsevier B.V. All rights reserved.Gallium-bearing magnetite particles were synthesized by aerial oxidation of alkaline suspension containing both ferrous and gallium ions. It was found that the mixing procedure and temperature were critical in the preparation of ferrite particles without the formation of alpha-FeOOH (ferric oxyhydroxide), non-spherical particles and amorphous phase, evidenced by characterization of SEM and XRD. On the other band, the concentration of Ga3+ entry into the structure of spinel was different with the mixing procedure and temperature. Single phase of spinel gallium-bearing magnetites were precipitated at the temperature from 25 to 90 degrees C in the C procedure in which the neutralization of Ga was performed firstly, but the concentration of Ga entry into spinel of magnetites decreased with the temperature increasing. While in the procedure D in which neutralization of Fe ions was performed firstly, single phase of spinel gallium-bearing magnetites were precipitated only at the temperature above 65 degrees C, and the content of gallium precipitated into the magnetites increased with the temperature. Mossbauer analysis and magnetic characteristic were used to investigate the cation distribution of the gallium bearing ferrites with different ratio of Ga3+/Fe2+, which showed small content gallium introduction to have entered the tetrahedral sites preferentially rather than the octahedral sites, and increasing gallium introduction to have located between octahedral and tetrahedral sites. (c) 2007 Elsevier B.V. All rights reserved

    J. Alloy. Compd.

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    CoFe2O4 magnetic particles were prepared by co-precipitation method in 60 degrees C homogeneous aqueous solution without any subsequent heat treatment. It was found that the mixing procedure and Fe2+/Fe3+ ratio of initial solution were critical in the preparation of CoFe2O4 particles in particle size, magnetization characters, uniformity in particle size and even cation distribution in spinel structure. Two different procedures were used to precipitate CoFe2O4 magnetic particles. Evidenced by XRD, Mossbauer analyses and magnetization determination, particles in comparative uniformity average size were obtained in procedure A, denoted as normal pH regulation procedure, in which NaOH solution was dropped into the mixture solution of iron ions, and with the decreasing in Fe2+/Fe3+ ratio of initial solution, the particle size decreased, which followed the same rule of diversification in saturation magnetization. Uniformity in particle size lowered when procedure B, referred to as reverse pH regulation procedure, where ferrous and cobalt ions were dropped into alkaline solution, was used to precipitate CoFe2O4, In both procedures, with the decreasing in Fe2+/Fe3+ ratio of initial solution, the saturation magnetization decreased, while the magnetic coercivity decreased but increased sharply when Fe2+/Fe3+ ratio of initial solution was 0. (C) 2007 Elsevier B.V. All rights reserved.CoFe2O4 magnetic particles were prepared by co-precipitation method in 60 degrees C homogeneous aqueous solution without any subsequent heat treatment. It was found that the mixing procedure and Fe2+/Fe3+ ratio of initial solution were critical in the preparation of CoFe2O4 particles in particle size, magnetization characters, uniformity in particle size and even cation distribution in spinel structure. Two different procedures were used to precipitate CoFe2O4 magnetic particles. Evidenced by XRD, Mossbauer analyses and magnetization determination, particles in comparative uniformity average size were obtained in procedure A, denoted as normal pH regulation procedure, in which NaOH solution was dropped into the mixture solution of iron ions, and with the decreasing in Fe2+/Fe3+ ratio of initial solution, the particle size decreased, which followed the same rule of diversification in saturation magnetization. Uniformity in particle size lowered when procedure B, referred to as reverse pH regulation procedure, where ferrous and cobalt ions were dropped into alkaline solution, was used to precipitate CoFe2O4, In both procedures, with the decreasing in Fe2+/Fe3+ ratio of initial solution, the saturation magnetization decreased, while the magnetic coercivity decreased but increased sharply when Fe2+/Fe3+ ratio of initial solution was 0. (C) 2007 Elsevier B.V. All rights reserved

    Dynamic Organization of lncRNA and Circular RNA Regulators Collectively Controlled Cardiac Differentiation in Humans

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    Advances in developmental cardiology have increased our understanding of the early aspects of heart differentiation. However, understanding noncoding RNA (ncRNA) transcription and regulation during this process remains elusive. Here, we constructed transcriptomes for both long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) in four important developmental stages ranging from early embryonic to cardiomyocyte based on high-throughput sequencing datasets, which indicate the high stage-specific expression patterns of two ncRNA types. Additionally, higher similarities of samples within each stage were found, highlighting the divergence of samples collected from distinct cardiac developmental stages. Next, we developed a method to identify numerous lncRNA and circRNA regulators whose expression was significantly stage-specific and shifted gradually and continuously during heart differentiation. We inferred that these ncRNAs are important for the stages of cardiac differentiation. Moreover, transcriptional regulation analysis revealed that the expression of stage-specific lncRNAs is controlled by known key stage-specific transcription factors (TFs). In addition, circRNAs exhibited dynamic expression patterns independent from their host genes. Functional enrichment analysis revealed that lncRNAs and circRNAs play critical roles in pathways that are activated specifically during heart differentiation. We further identified candidate TF-ncRNA-gene network modules for each differentiation stage, suggesting the dynamic organization of lncRNAs and circRNAs collectively controlled cardiac differentiation, which may cause heart-related diseases when defective. Our study provides a foundation for understanding the dynamic regulation of ncRNA transcriptomes during heart differentiation and identifies the dynamic organization of novel key lncRNAs and circRNAs to collectively control cardiac differentiation

    Adsorption Behaviors of Organic Micropollutants on Zirconium Metal–Organic Framework UiO-66: Analysis of Surface Interactions

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    Herein, we studied the adsorption behaviors of organic micropollutants, such as anticonvulsant carbamazepine (CBZ) and antibiotic tetracycline hydrochloride (TC), on zirconium metal–organic framework UiO-66 in water. The maximum adsorption capacities of CBZ and TC on the UiO-66 were 37.2 and 23.1 mg·g<sup>–1</sup> at 25 °C, respectively. The adsorption isotherms and kinetics of CBZ and TC were well described by using the Langmuir model and pseudo-second-order model, respectively, and the adsorptions on UiO-66 are endothermic reactions. The adsorption capacities of CBZ and TC on UiO-66 were decreased with the increase of solution pH. The presence of humic acid could improve the adsorption of CBZ and TC on UiO-66, but K<sup>+</sup> ion inhibited their adsorption obviously. In addition, Ca<sup>2+</sup> and Al<sup>3+</sup> ions also suppressed the adsorption of TC on UiO-66. The competitive adsorption suggested that the adsorption sites for CBZ on UiO-66 were different from those for TC. The surface interactions between UiO-66 and the two micropollutants were demonstrated by powder X-ray diffraction, Fourier transform infrared (FT-IR) spectra, scanning electron microscopy, nitrogen adsorption/desorption isotherms, and X-ray photoelectron (XPS) spectra. The characterizations showed that the adsorption of CBZ on UiO-66 is mainly a physisorption, and the hydrophobic effect played a crucial role during the adsorption of CBZ; meanwhile weak π–π electron donor–acceptor interaction and electrostatic attraction also existed. However, the adsorption of TC on UiO-66 is mainly a chemisorption; in addition to the strong electrostatic attraction and π–π electron donor–acceptor interaction forces, the nitrogenous groups of TC played an important role, which can replace the carboxylic groups coordinated with Zr–O clusters. The obtained results will aid us to comprehend the surface interaction between organic micropollutants and UiO-66 and expand the application of UiO-66 as sorbent for removal of pollutants from water

    High Expression of HERV-K (HML-2) Might Stimulate Interferon in COVID-19 Patients

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    Background. Interferon is a marker of host antiviral immunity, which is disordered in COVID-19 patients. ERV can affect the secretion of interferon through the cGAS-STING pathway. In this study, we explored whether IFN-I and HERV-K (HML-2) were activated in COVID-19 patients and whether there was an interaction between them. Methods. We collected blood samples from COVID-19 patients and healthy controls. We first detected the expression of HERV-K (HML-2) gag, env, and pol genes and IFN-I-related genes between patients and healthy people by qPCR, synchronously detected VERO cells infected with SARS-CoV-2. Then, the chromosome distributions of highly expressed HERV-K (HML-2) gag, env, and pol genes were mapped by the next-generation sequencing results, and GO analysis was performed on the related genes. Results. We found that the HERV-K (HML-2) gag, env, and pol genes were highly expressed in COVID-19 patients and VERO cells infected with SARS-CoV-2. The interferon-related genes IFNB1, ISG15, and IFIT1 were also activated in COVID-19 patients, and GO analysis showed that HERV-K (HML-2) can regulate the secretion of interferon. Conclusions. The high expression of HERV-K (HML-2) might activate the increase of interferon in COVID-19 patients, proving that HERV-K does not only play a negative role in the human body

    An Active Bacterial Anti-adhesion Strategy Based on Directional Transportation of Bacterial Droplets Driven by Triboelectric Nanogenerators

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    An active bacterial anti-adhesion strategy based on directional transportation of bacterial droplets driven by a triboelectric nanogenerator (TENG) has not been reported to date, although passive defense approaches can prevent bacterial adhesion by regulating superwetting surfaces combined with incorporated antibacterial substances. Here a triboelectric nanogenerator driving droplet system (TNDDS) was built to drive directional transportation of bacterial droplets to be eliminated, which comprises TENG with periodical frictional Kapton film and aluminum foils and a superhydrophobic driving platform (SDP) with paralleled driving electrodes. The current generated by the TENG triboelectricity is transmitted to the paralleled driving electrodes to form an electric field driving the directional transportation of charged droplets. The critical value of the driven droplet volume on SDP is closely related to the distributed electrodes’ distance and width, and the driving distance of droplets is related to the number of electrodes. More crucially, TNDDS can actively drive the charged droplets of prepared triangular silver nanoprisms (Ag NPs) forward and back to mix with and remove a tiny bacterial droplet on an open SDP or in a tiny semi-enclosed channel. Bacteria could be killed by releasing Ag+ and effectively removed by TNDDS by regulating the motion direction. Generally, this approach offers a promising application for removing bacteria from material surfaces driven by TENG and opens a new avenue for bacterial anti-adhesion
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