Analysis on spatial heterogeneity of ecological restoration demand in resource-based cities: taking Jiawang District of Xuzhou city as an example

After a long period of coal resource exploitation in resource-based cities, the imbalance and disharmony between resource development and ecological protection in coal mining areas are prominent. In the context of ecological civilization construction, clarifying the spatial heterogeneity of ecological restoration needs and reasonably arranging the priority of ecological restoration work will become the basic work for efficient and coordinated ecological protection and restoration, which will help to plan as a whole, coordinate and orderly promote the high-quality sustainable development of resource-based cities. From the comprehensive perspective of the coordinated development of ecosystem and human well-being, Jiawang District, Xuzhou City, was selected as an example, and the historical remote sensing images, historical mine information and social and economic statistics in 2000, 2010 and 2019 were taken as the data sources. The equivalent assignment method was used to calculate the regional ecosystem service value and make coefficient correction. The landscape ecological risk assessment system was constructed by integrating the topographic location index, mining area disturbance index and landscape vulnerability index. The spatial and temporal patterns of ecosystem service value and ecological risk index in the study area were analyzed, and the sharpe ratio was introduced to further explore the spatial heterogeneity of ecological restoration needs. The results showed that: ① From 2000 to 2019, the total value of ecosystem services in Jiawang district increased first and then decreased, and the value of ecological risk index decreased first and then increased. The growth rate was relatively flat, showing a small range; the spatial distribution of ecological service value and ecological risk level shows a trend of overall connectivity, with local circles moving outward. Urbanization and coal mining subsidence land management are the main factors influencing the spatial pattern differentiation. ② At the quantitative level, the ecosystem service value per unit area and the ecological risk index have strong negative grade correlations, but there is no obvious functional relationship; At the spatial level, the overall Moran’s I index of unit ecosystem service value and ecological risk index in Jiawang District from 2000 to 2019 were negative, showing negative spatial correlation. Ecological risks and ecosystem services have obvious dislocation characteristics. ③ The heterogeneity index R of ecological restoration demand in Jiawang district presents a gradient spatial change trend to a certain extent, and the overall ecological restoration demand tends to decrease, but the R index is still too high or too low in some regions; with the increase of degree of deviation, the range of high value areas for ecological restoration needs gradually narrowed and transformed to low value areas, and the areas requiring key ecological construction tend to be more centralized. The research conclusion can provide reference for the decision-making arrangement of systematic and integrated ecological restoration of resource exhausted cities

An ancestral NB-LRR with duplicated 3'UTRs confers stripe rust resistance in wheat and barley.

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a global threat to wheat production. Aegilops tauschii, one of the wheat progenitors, carries the YrAS2388 locus for resistance to Pst on chromosome 4DS. We reveal that YrAS2388 encodes a typical nucleotide oligomerization domain-like receptor (NLR). The Pst-resistant allele YrAS2388R has duplicated 3' untranslated regions and is characterized by alternative splicing in the nucleotide-binding domain. Mutation of the YrAS2388R allele disrupts its resistance to Pst in synthetic hexaploid wheat; transgenic plants with YrAS2388R show resistance to eleven Pst races in common wheat and one race of P. striiformis f. sp. hordei in barley. The YrAS2388R allele occurs only in Ae. tauschii and the Ae. tauschii-derived synthetic wheat; it is absent in 100% (n = 461) of common wheat lines tested. The cloning of YrAS2388R will facilitate breeding for stripe rust resistance in wheat and other Triticeae species

Distinct Response of Irradiated Normal Human Fibroblasts and Their Bystander Cells to Heavy-Ion Radiation in Confluent Cultures

INTRODUCTION Biological effectiveness varies with the linear energy transfer (LET) of ionizing radiation. During cancer therapy or manned space explorations, humans are exposed to high-LET heavy ions, which inactivate irradiated cells more effectively than low-LET photons like X-rays and gamma-rays1. Over the past 16 years, convincing experimental evidence has been presented demonstrating that radiation induces biological effects in non-irradiated bystander cells having received signals from directly irradiated cells2; however, little information is available heretofore concerning the bystander response to heavy ions. Taking into consideration that less irradiated cells coexist with more non-irradiated counterparts in a population exposed to a lower dose of higher-LET heavy ions, the effects arising not merely in irradiated cells but in their bystander cells should be characterized to comprehend the mechanism of heavy-ion action. Here, we set out to investigate the potential impact of heavy ions on the bystander effect, and compare the response of irradiated and bystander cells in confluent human fibroblasts.\nMATERIALS AND METHODS Confluent density-inhibited cultures of AG01522D normal human fibroblasts3,4 were used, and irradiation was conducted at the TIARA facility of JAEA. To see the bystander effect, only 0.0003% of the cells were targeted with microbeams of carbon ions (18.3 MeV/u, 103 keV/µm)5, so that the vast majority of the cells could be considered as non-irradiated bystander cells. The cells were also irradiated with conventional broadbeams of carbon ions (18.3 MeV/u, 108 keV/µm) to see the effects in irradiated cells6-8. Cell survival was determined with the clonogenic assay, apoptosis with the TUNEL staining, the levels of serine 15-phosphorylated p53 proteins with western blotting, and gene expression profiles with the microarray analysis.\nRESULTS AND DISCUSSION Bystander cells showed nearly 10% reductions in the survival9. Whereas apoptotic frequency in irradiated cells increased with time up to 72 h postirradiation, its frequency in bystander cells was elevated twofold at 24 h but declined at 48 h9, suggesting that bystander cells exhibit transient commitment to apoptosis. Whilst the levels of phosphorylated p53 proteins in irradiated cells escalated and remained unchanged at 2 and 6 h, its levels in bystander cells rose twofold at 6 h but not at 2h9, indicating that bystander cells undergo delayed p53 phosphorylation. More than half of the genes whose expression changed at 2 and 6 h in bystander cells were downregulated, and most of the genes upregulated in irradiated cells were downregulated in bystander cells10, suggesting different expression profiles between irradiated and bystander cells. Pathway analysis revealed serial activation of G protein/PI-3 kinase pathway in bystander cells, but NF-kappaB and p21Waf1 pathways in irradiated cells10. Interleukin genes were upregulated in irradiated cells while its receptor gene was upregulated in bystander cells10, indicating the signal transmission from irradiated to bystander cells. The bystander effect for the survival and apoptosis was observed similarly irrespective of whether the cells were targeted with microbeams of carbon ions or two types of neon ions (17.5 MeV/u, 294 keV/µm; 13.0 MeV/u, 375 keV/µm)11. With respect to the medium-mediated bystander effect of X-rays (5 keV/µm) and neon ions (13.0 MeV/u, 437 keV/µm) for chromosome aberrations, there was a difference in the types of aberrations but little difference in total yields12. It seems thence likely that the bystander effect is independent of LET, but that its underpinning causes differ with the radiation quality.\nCONCLUSION The bystander effect of heavy ions was manifested as inactivated clonogenic potential, a transient apoptotic response, delayed p53 phosphorylation, and alterations in gene expression at a genome-wide level. Our findings highlight distinct response of irradiated and bystander cells. Such response of normal fibroblasts could be a defensive mechanism that would avert further expansion of aberrant cells, thus maintaining genome integrity and cellular homeostasis.\nACKNOWLEDGEMENTSThis work was supported in part by a Grant-in-aid for the 21st Century Center of Excellence (COE) Program for Biomedical Research Using Accelerator Technology from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan, and by the Budget of Nuclear Research of the MEXT based on the screening and counseling by the Atomic Energy Commission of Japan.\nREFERENCES1) Hamada N, J Radiat Res 50: in press, 2009 (doi: 10.1269/jrr.08070).2) Hamada N, et al., J Radiat Res 48: 87-95, 2007.3) Hamada N, et al., Radiat Res 166: 24-30, 2006.4) Hamada N, et al., Mutat Res 637: 190-196, 2008.5) Funayama T, Hamada N, et al., IEEE Trans Plasma Sci 36: 1432-1440, 2008.6) Hamada N, et al., Cancer Lett 268: 76-81, 2008.7) Hamada N, et al., Radiother Oncol 89: 227-230, 2008.8) Hamada N, et al., Radiother Oncol 89: 231-236, 2008.9) Hamada N, et al., Mutat Res 639: 35-44, 2008.10) Iwakawa M, Hamada N, et al., Mutat Res 642: 57-67, 2008.11) Hamada N, et al., Biol Sci Space 22: 46-53, 2008.12) Kanasugi Y, Hamada N, et al., Int J Radiat Biol 83: 73-80, 2007.8th International Workshop on Microbeam Probes of Cellular Radiation Respons

The Bystander Effect of Heavy Ions in Confluent Human Fibroblasts

Significant evidence has been presented demonstrating that ionizing radiation induces biological effects in nonirradiated bystander cells having received signals from directly irradiated cells [1]; however, little information exists on the bystander effect of heavy ions. Less irradiated cells should coexist with more nonirradiated counterparts in a population exposed to a lower dose of higher-LET heavy ions, so that an elucidation of the effects arising not merely in irradiated cells but in their bystander cells would be crucial to comprehend the mechanism of action of heavy ions. Here we have investigated heavy ion-induced bystander response in confluent human fibroblast cultures. First, precise microbeams were employed to target 0.0003% of cells [2]. Conventional broadfield irradiation was carried out in parallel to see the effects in irradiated cells [3-6]. Intriguingly, bystander cells manifested a more transient apoptotic response and delayed p53 phosphorylation, compared with irradiated cells [7]. Taken together, nearly three quarters of the genes whose expression changed in bystander cells were downregulated, and most of the genes upregulated in irradiated cells were downregulated in bystander cells [8]. These findings highlight the distinct response of irradiated and bystander cells. Furthermore, interleukin genes were upregulated in irradiated cells whereas its receptor gene was upregulated in bystander cells [8], suggestive of the signal transmission from irradiated to bystander cells. Second, chromosome aberrations were analyzed in cells treated with conditioned medium from X- or heavy ion-irradiated cells. We found the difference in the types of aberrations, but very little in the total aberration yields [9], indicating that bystander responses occur independently of radiation types but are induced through different mechanisms. Collectively, these induced bystander responses could be a defensive mechanism that would avert or minimize further expansion of aberrant cells.10th International Workshop on Radiation Damage to DN