Granulocyte colony-stimulating factor affects the distribution and clonality of TRGV and TRDV repertoire of T cells and graft-versus-host disease

<p>Abstract</p> <p>Background</p> <p>The immune modulatory effect of granulocyte colony-stimulating factor (G-CSF) on T cells resulted in an unexpected low incidence of graft-versus-host disease (GVHD) in allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Recent data indicated that gamma delta⁺T cells might participate in mediating graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect after allogeneic hematopoietic stem cell transplantation. However, whether G-CSF could influence the T cell receptors (TCR) of gamma delta⁺T cells (<it>TRGV </it>and <it>TRDV </it>repertoire) remains unclear. To further characterize this feature, we compared the distribution and clonality of <it>TRGV </it>and <it>TRDV </it>repertoire of T cells before and after G-CSF mobilization and investigated the association between the changes of TCR repertoire and GVHD in patients undergoing G-CSF mobilized allo-PBSCT.</p> <p>Methods</p> <p>The complementarity-determining region 3 (CDR3) sizes of three <it>TRGV </it>and eight <it>TRDV </it>subfamily genes were analyzed in peripheral blood mononuclear cells (PBMCs) from 20 donors before and after G-CSF mobilization, using RT-PCR and genescan technique. To determine the expression levels of <it>TRGV </it>subfamily genes, we performed quantitative analysis of <it>TRGV</it>I~III subfamilies by real-time PCR.</p> <p>Results</p> <p>The expression levels of three <it>TRGV </it>subfamilies were significantly decreased after G-CSF mobilization (<it>P </it>= 0.015, 0.009 and 0.006, respectively). The pattern of <it>TRGV </it>subfamily expression levels was <it>TRGV</it>II ><it>TRGV </it>I ><it>TRGV </it>III before mobilization, and changed to <it>TRGV </it>I ><it>TRGV </it>II ><it>TRGV </it>III after G-CSF mobilization. The expression frequencies of <it>TRGV </it>and <it>TRDV </it>subfamilies changed at different levels after G-CSF mobilization. Most <it>TRGV </it>and <it>TRDV </it>subfamilies revealed polyclonality from pre-G-CSF-mobilized and G-CSF-mobilized samples. Oligoclonality was detected in <it>TRGV </it>and <it>TRDV </it>subfamilies in 3 donors before mobilization and in another 4 donors after G-CSF mobilization, distributed in <it>TRGV</it>II, <it>TRDV</it>1, <it>TRDV</it>3 and <it>TRDV</it>6, respectively. Significant positive association was observed between the invariable clonality of <it>TRDV</it>1 gene repertoire after G-CSF mobilization and low incidence of GVHD in recipients (<it>P </it>= 0.015, <it>OR </it>= 0.047).</p> <p>Conclusions</p> <p>G-CSF mobilization not only influences the distribution and expression levels of <it>TRGV </it>and <it>TRDV </it>repertoire, but also changes the clonality of gamma delta⁺T cells. This alteration of <it>TRGV </it>and <it>TRDV </it>repertoire might play a role in mediating GVHD in G-CSF mobilized allo-PBSCT.</p

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

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

Distribution, fluxes and decadal changes of nutrients in the Jiulong River Estuary, Southwest Taiwan Strait

The Jiulong River Estuary (JRE) is a typical subtropical macro-tide estuary on the southwest coast of the Taiwan Strait (TWS), which has been greatly impacted by human activities over the past 30 years. To understand nutrient dynamics and fluxes under such a heavy background of anthropogenic perturbation, eight cruises were conducted from April 2008 to April 2011, covering both wet (May to September) and dry (October to April next year) seasons. Nutrient concentrations were very high for the freshwater end-member in the upper reach of the JRE (nitrate (NO3-N): 120-230 mu mol L-1; nitrite (NO2-N): 5-15 mu mol L-1; ammonium (NH4-N): 15-170 mu mol L-1; soluble reactive phosphorus (SRP): 1.2-3.5 mu mol L-1; dissolved silicate (DSi): 200-340 mu mol L-1). In dry seasons, concentrations of these nutrients were higher than in wet seasons. Nitrate was the dominant chemical species of dissolved inorganic nitrogen (DIN), with percentages of 67%-96% in wet seasons and 55%-72% in dry seasons. Distributions of NO3-N and DSi against salinity were nearly constant during all cruises, and showed generally conservative mixing behaviors in the estuary (1 < Salinity < 32). The concentrations of SRP varied within a narrow range of 1.0-2.0 mu mol L-1 in low/middle salinity areas, and they were quickly diluted by relatively oligotrophic near-shore seawater in the high salinity region. Based on a temporally high-resolution water discharge dataset, riverine fluxes of DIN, SRP and DSi into the JRE were calculated at 34.3x10(3) t N a(-1), 0.63x10(3) t P a(-1) and 72.7x10(3) t Si a(-1), respectively. In comparison, estuarine export fluxes of DIN, SRP and DSi from the JRE to the TWS were estimated at 34.8x10(3) t N a(-1), 0.82x10(3) t P a(-1) and 71.6x10(3) t Si a(-1). The estuarine addition flux of SRP was independently estimated at 0.16x10(3) t P a(-1). In comparison with major world rivers, the Jiulong River shows a very high areal yield rate of NO3-N. In comparison with historical datasets from 1980s-1990s, concentrations of NO3-N and SRP increased 2-3 times in upper/middle areas of the JRE, while DSi remained at the same level. The latter is much different from decadal nutrient changes in the Mississippi River and the Yangtze River/Estuary. Such nutrient changes may fundamentally contribute to recent red tide events in the JRE and adjacent Xiamen Bay.National Natural Science Foundation of China (NSFC) [40810069004]; National Basic Research Program of China [2009CB421204]; State Oceanic Administration of China [DOMEP-MEA-01-10

Outcome of infants with acute lymphoblastic leukemia treated with the Chinese Children's Cancer Group Acute Lymphoblastic Leukemia 2015 study protocol

Not available

Evaluation of Factors Affecting Student Participation in Peer-Assisted English Learning Based on Online Education Platform

Through a questionnaire survey, this study explored the factors affecting student participation in peer-assisted English learning (PAEL) based on online education platforms. Specifically, the authors constructed the system of PAEL contents, analyzed the online PAEL behaviors of students, and evaluated the student participation in online PAEL from both surface participation and deep participation. On this basis, the influencing factors of student participation in online PAEL were evaluated thoroughly. In the end, several countermeasures were presented to solve the problems with student participation in online PAEL. The results show that: the online PAEL face such problems like low-level knowledge structure and poor interaction quality, weak intensity of interaction, and inactive atmosphere of collaboration; In general, the students are not actively participating in online PAEL; the student participation in online PAEL is greatly affected by teachers, students, teaching contents, and online education platforms; the low participation in online PAEL mainly arises from the weak motives of students for online PAEL, the inadequate teaching design and supervision of teachers, and the imperfect functions of online education platform. The research enriches the theoretical and practical results on the factors affecting student participation in online PAEL

Specific alterations in mucosa-associated bacterial composition in ulcerative colitis (UC) patients with different degrees of inflammation

AbstractThe aim of this study is to evaluate the specific bacterial communities and alterations and to explore the method predicting the microbiological evolution tendency of ulcerative colitis (UC) patients. A total of 29 UC patients and 18 healthy subjects (HS) were enrolled. UC patients were grouped into mild, moderate and severe UC based on the Mayo Score. The bacterial types of the groups were distinctly different with each other on different classification levels. Interestingly, the bacterial composition of severe UC was distinctly different from others. The Chao and Ace indices of bacterial microbiota were significantly higher in the severe UC group. The main phyla in UC and HS were Firmicutes, Bacteroidetes and Proteobacteria. The percentage of the 3 main phyla in severe UC was lower than that in non-severe UC. Similar to the other groups, the main genera in severe UC were Bacteroides and Escherichia-Shigella. However, Parabacteroides and a type of Prevotella disappeared in the severe UC group. Some types, such as Faecalibacterium and Fusobacterium, decreased. On the contrary, the other types increased. The abundance of the putative pathogenic bacteria in mild UC, moderate UC and severe UC showed an increasing trend (9:11:115). Moreover, Bacillus, Lactococcus and Alloprevotella disappeared in UC. Parabacteroides and a type of Prevotella disappeared in severe UC. Serious dysbacteriosis and abundant putative pathogenic bacteriа are the two important features of severe UC. The percentage phyla and the abundance of putative pathogenic bacteria could be used to predict the evolution tendency

The distribution and accumulation of mercury and methylmercury in surface sediments beneath the East China Sea

Abstract China is a massive mercury emitter, responsible for a quarter of the world’s mercury emissions, which transit the atmosphere and accumulate throughout its watercourses. The Changjiang (Yangtze) River is the third largest river in the world, integrating mercury emissions over its 1.8 × 106 km2 catchment and channelling them to the East China Sea where they can be buried. Despite its potential global significance, the importance of the East China Sea as a terminal mercury sink remains poorly known. To address this knowledge gap, total mercury and methylmercury concentrations were determined from 51 surface sediment samples revealing their spatial distribution, whilst demonstrating the overall pollution status of the East China Sea. Sedimentary mercury distributions beneath the East China Sea are spatially heterogeneous, with high mercury concentrations (> 25 ng g−1) corresponding to areas of fine-grained sediment accumulation. In contrast, some sites of fine-grained sediment deposition have significantly lower values of methylmercury (< 15 ng g−1), such as the Changjiang estuary and some isolated offshore areas. Fine-grained particles and organic matter availability appear to exert the dominant control over sedimentary mercury distribution in the East China Sea, whereas in situ methylation serves as an additional control governing methylmercury accumulation. Estimated annual sedimentary fluxes of mercury in the East China Sea are 51 × 106 g, which accounts for 9% of China’s annual mercury emissions

Effects of Stocking Density on Intestinal Health of Juvenile <i>Micropterus salmoides</i> in Industrial Aquaponics

Stocking density is a key factor affecting the health of aquatic organisms in industrial aquaponics. In this study, Micropterus salmoides were assigned to one of two density groups (160 and 120 fish/m3) for 40 days. The growth performance, intestinal morphology, enzyme activity, and microbial communities were compared between the two density groups. The findings revealed that the higher stocking density condition exhibited an increased weight gain rate and specific growth rate during the developmental phase of the juvenile M. salmoides. Moreover, remarkable increases in villi height, villi width, and muscular layer thickness were observed. Additionally, this elevated stocking density condition also enhanced the activity of intestinal antioxidant enzymes, consequently improving the structural integrity of the intestine and augmenting the digestive and absorptive capacities of the juvenile M. salmoides. With regard to the intestinal microbial community, the dominant phyla detected were Firmicutes and Proteobacteria. However, under the higher stocking density condition, there was a significant upsurge in the abundance of Mycoplasma. Consequently, it is advised to mitigate the abundance of such pathogenic microorganisms through the regulation of the water environment during the aquacultural process. Drawing from recent investigations on the impact of various factors on the intestinal microbiota of M. salmoides, it can be deduced that the composition of the intestinal microbiota is closely intertwined with factors including aquaculture practices, feed composition, water environment, and developmental stage. In summary, the aforementioned research findings possess noteworthy implications for the control of stocking density in the cultivation of juvenile M. salmoides

Clinical characteristics and spectrum of NF1 mutations in 12 unrelated Chinese families with neurofibromatosis type 1

Abstract Background Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder caused by a heterozygous germline mutation in the tumor suppressor gene NF1. Because of the existence of highly homologous pseudogenes, the large size of the gene, and the heterogeneity of mutation types and positions, the detection of variations in NF1 is more difficult than that for an ordinary gene. Methods In this study, we collected samples from 23 patients among 46 study participants from 12 unrelated Chinese families with NF1. We used a combination of Sanger sequencing, targeted next-generation sequencing, and multiplex ligation-dependent probe amplification to identify potential mutations of different types. Results Seven recurrent mutations and four novel mutations were identified with the aforementioned methods, which were subsequently confirmed by either restriction fragment length polymorphism analysis or Sanger sequencing. Truncating mutations accounted for 73% (8/11) of all mutations identified. We also exhaustively investigated the clinical manifestations of NF1 in patients via acquired pathography, photographs and follow-up. However, no clear genotype–phenotype correlation has been found to date. Conclusion In conclusion, the novel mutations identified broaden the spectrum of NF1 mutations in Chinese; however, obvious correlations between genotype and phenotype were not observed in this study