The IRP1-HIF-2α Axis Coordinates Iron and Oxygen Sensing with Erythropoiesis and Iron Absorption

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Highlights? Derepression of HIF-2α mRNA in Irp1^?/? mice causes age-dependent polycythemia ? HIF-2α hyperactivity is observed in multiple tissues of Irp1^?/? mice ? The mRNA regulons of IRP1 and IRP2 are separable in vivo ? The IRP1-HIF-2α axis is a therapeutic target for hematologic or oncologic disorders     

Tangshenosides from Codonopsis lanceolata roots

A new symmetrical phenylpropanoid glycoside, tangshenoside VIII (1), together with six known tangshenosides (2–7) were isolated from the roots of Codonopsis lanceolata (Campanulaceae). Their structures were established on the basis of spectroscopic data, including two-dimensional NMR analyses. Tangshenosides have chemotaxonomic significance.     

Sinomenine hydrochloride enhancement of the inhibitory effects of anti-transferrin receptor antibody-dependent on the COX-2 pathway in human hepatoma cells

Transferrin receptor (TfR) has been used as a target for the antibody-based therapy of cancer due to its higher expression in tumors relative to normal tissues. Great potential has been shown by anti-TfR antibodies combined with chemotherapeutic drugs as a possible cancer therapeutic strategy. In our study, we investigated the anti-tumor effects of anti-TfR monoclonal antibody (mAb) alone or in combination with sinomenine hydrochloride in vitro. Results suggested that anti-TfR mAb or sinomenine hydrochloride could induce apoptosis, inhibit proliferation, and affect the cell cycle. A synergistic effect was found in relation to tumor growth inhibition and the induction of apoptosis when anti-TfR mAb and sinomenine hydrochloride were used simultaneously. The expression of COX-2 and VEGF protein in HepG2 cells treated with anti-TfR mAb alone was increased in line with increasing dosage of the agent. In contrast, COX-2 expression was dramatically decreased in HepG2 cells treated with sinomenine hydrochloride alone. Furthermore, we demonstrated that the inhibitory effects of sinomenine hydrochloride and anti-TfR mAb administered in combination were more prominent than when the agents were administered singly. To sum up, these results showed that the combined use of sinomenine hydrochloride and anti-TfR mAb may exert synergistic inhibitory effects on human hepatoma HepG2 cells in a COX-2-dependent manner. This finding provides new insight into how tumor cells overcome the interference of iron intake to survive and forms the basis of a new therapeutic strategy involving the development of anti-TfR mAb combined with sinomenine hydrochloride for liver cancer.     

Three new synonyms of Macromitrium microstomum (Hook. & Grev.) Schwägr. (Bryophyta,Orthotrichaceae), with comments on its morphological variations

Macromitrium filicaule Müll.Hal., M. pacificum var. brevisetum Thér. and M. subnitidum Müll.Hal are placed in synonymy with Macromitrium microstomum (Hook. & Grev.) Schwägr. The morphological variations of M. microstomum branch leaves, perichaetial leaves and capsules are illustrated by digital images.     

An estimation of Canadian population exposure to cosmic rays from air travel

Based on air travel statistics in 1984, it was estimated that less than 4 % of the population dose from cosmic ray exposure would result from air travel. In the present study, cosmic ray doses were calculated for more than 3,000 flights departing from more than 200 Canadian airports using actual flight profiles. Based on currently available air travel statistics, the annual per capita effective dose from air transportation is estimated to be 32 μSv for Canadians, about 10 % of the average cosmic ray dose received at ground level (310 μSv per year).     

Molecular Cloning and Expression Analysis of Nine ThTrx Genes in Tamarix hispida

Thioredoxins are small conserved proteins that play key roles in the oxidative stress response. In this study, nine Trx genes, including five Trxhs, three Trxms, and one Trx-like gene, were cloned from Tamarix hispida. The roles of these ThTrx genes were investigated under various abiotic stress conditions. Expression profiles of the nine ThTrx genes in response to different abiotic stresses in leaf and root tissues were constructed using quantitative real time-polymerase chain reaction. Differential expression of all nine ThTrx genes was observed (>2-fold) in response to NaCl, PEG, or CdCl₂ stress in at least one tissue, indicating that all of these genes act in abiotic stress responses. All ThTrx genes were induced (>2-fold) by abscisic acid (ABA) treatment in the leaves and especially in the roots, suggesting that ABA-dependent signaling pathways regulate ThTrxs. These results demonstrate that ThTrx expression constitutes an adaptive response to abiotic stress in T. hispida and plays an important role in abiotic stress tolerance.     

Intermediate herbivory intensity of an aboveground pest promotes soil labile resources and microbial biomass via modifying rice growth

Background and Aims

The importance of aboveground herbivores for modifying belowground ecosystems has prompted numerous studies; however, studies can be biased by context dependent conditions which lead to extremely inconsistent results. So far, the impacts of herbivory intensity by important rice pests on rice paddy soil ecosystems are lacking. The aim of this study was to test the hypothesis that intermediate herbivory intensity of the brown planthopper (Nilaparvata lugens Stål) could promote soil labile resources and microbial biomass, while high intensity would show a reverse pattern, by mediating rice plant growth. This study will also help the development of integrative pest management.

Methods

Four hopper infestation density treatments (0, 4, 8 and 12 nymphs per rice plant) and two infestation duration treatments (9 and 15 days after N. lugens infestation, DAI 9 and DAI 15) were established in a glasshouse experiment. Soil and plant were sampled destructively from four replicates and analysed for soil labile resources availability, soil microbial biomass and plant performance, respectively.

Results

The infestation density significantly affected both shoot and root mass of rice (P?<?0.05), soil dissolved organic carbon (DOC) and nitrogen (DON), and microbial biomass carbon (MBC) and nitrogen (MBN), and the effects were further enhanced by prolonged infestation duration. Compared to the control (CK) without N. lugens, plant dry mass, DOC, DON, MBC and MBN increased under low (LD) and moderate hopper densities (MD) but decreased under high density (HD) on DAI 9. Moreover, the LD treatment exerted the most promotional effects on DAI 15. Rice root to shoot ratio generally increased in treatments subjected to herbivory. The labile resources and microbial biomass showed close relationships with both shoot and root mass across treatments, in particular with root mass on DAI 15. Such a trend indicated that the shift of photosynthate allocation to belowground contributed to changes of soil resource availability and microbial biomass.

Conclusions

Intermediate herbivory intensity showed positive effects on rice seedling performance and, further, promoted soil labile resource availability and microbial biomass. The importance of extrapolating temporal and spatial scale, i.e. from the short-term greenhouse experiment to an entire rice growing season in the field, was highlighted.