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Rice paddy soil-associated microbiota participate in biogeochemical processes that underpin rice yield and soil sustainability, yet continental-scale biogeographic patterns of paddy soil microbiota remain elusive. The soil bacteria of four typical Chinese rice-growing regions were characterized and compared to those of nonpaddy soils. The paddy soil bacteria were significantly less diverse, with unique taxonomic and functional composition, and harbored distinct cooccurrence network topology. Both stochastic and deterministic processes shaped soil bacteria assembly, but paddy samples exhibited a stronger deterministic signature than nonpaddy samples. Compared to other environmental factors, climatic factors such as mean monthly precipitation and mean annual temperature described most of the variance in soil bacterial community structure. Cooccurrence network analysis suggests that the continental biogeographic variance in bacterial community structure was described by the competition between two mutually exclusive bacterial modules in the community. Keystone taxa identified in network models (Anaerolineales, Ignavibacteriae, and Deltaproteobacteria) were more sensitive to changes in environmental factors, leading us to conclude that environmental factors may influence paddy soil bacterial communities via these keystone taxa. Characterizing the uniqueness of bacterial community patterns in paddy soil (compared to nonpaddy soils) at continental scales is central to improving crop productivity and resilience and to sustaining agricultural soils. IMPORTANCE Rice fields provide food for over half of the world's human population. The ecology of paddy soil microbiomes is shaped by human activities, which can have a profound impact on rice yield, greenhouse gas emissions, and soil health. Investigations of the soil bacteria in four typical Chinese rice-growing regions showed that (i) soil bacterial communities maintain highly modularized species-to-species network structures; (ii) community patterns were shaped by the balance of integrated stochastic and deterministic processes, in which homogenizing selection and dispersal limitation dominate; and (iii) deterministic processes and climatic and edaphic factors influence community patterns mainly by their impact on highly connected nodes (i.e., keystone taxa) in networks. Characterizing the unique ecology of bacterial community patterns in paddy soil at a continental scale may lead to improved crop productivity and resilience, as well as sustaining agricultural soils.

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BackgroundPaddy soil dissolved organic matter (DOM) represents a major hotspot for soil biogeochemistry, yet we know little about its chemodiversity let alone the microbial community that shapes it. Here, we leveraged ultrahigh-resolution mass spectrometry, amplicon, and metagenomic sequencing to characterize the molecular distribution of DOM and the taxonomic and functional microbial diversity in paddy soils across China. We hypothesized that variances in microbial community significantly associate with changes in soil DOM molecular composition.ResultsWe report that both microbial and DOM profiles revealed geographic patterns that were associated with variation in mean monthly precipitation, mean annual temperature, and pH. DOM molecular diversity was significantly correlated with microbial taxonomic diversity. An increase in DOM molecules categorized as peptides, carbohydrates, and unsaturated aliphatics, and a decrease in those belonging to polyphenolics and polycyclic aromatics, significantly correlated with proportional changes in some of the microbial taxa, such as Syntrophobacterales, Thermoleophilia, Geobacter, Spirochaeta, Gaiella, and Defluviicoccus. DOM composition was also associated with the relative abundances of the microbial metabolic pathways, such as anaerobic carbon fixation, glycolysis, lignolysis, fermentation, and methanogenesis.ConclusionsOur study demonstrates the continental-scale distribution of DOM is significantly correlated with the taxonomic profile and metabolic potential of the rice paddy microbiome. Abiotic factors that have a distinct effect on community structure can also influence the chemodiversity of DOM and vice versa. Deciphering these associations and the underlying mechanisms can precipitate understanding of the complex ecology of paddy soils, as well as help assess the effects of human activities on biogeochemistry and greenhouse gas emissions in paddy soils.

Neuron is the basic unit of nervous system. Studying the fine morphology of neurons is crucial for understanding the structure of neural network and the manner of neural information processing. At present, effective methods to visualize fine morphology of neurons with specific cell types and specific projection are still lacking. In this paper, a recombination vesicular stomatitis virus (VSV) was designed, with nucleoprotein gene mutated and glycoprotein gene deleted. The virus, VSV-△G-NR7A-EGFP, was capable of highlighted morphology of the labelled neurons in a short time. With specific transgenic animals and a helper virus rAAV-EF1α-Dio-Bfp-Tva, it was demonstrated that, a further constructed virus VSV-△G-EnvA-NR7A-EGFP could sparsely and specifically label D2R neurons with nucleus accumbens-lateral hypothalamus (NAc-LH) projection and dopamine neurons with ventral tegmental area (VTA)-NAc projection.

Quantitative analyses of molecular expression, cell counts and neural network connections among different brain regions are essential in brain science research. Based on Paxinos and Franklin's the Mouse Brain in Stereotaxic Coordinates (Ⅱ) and public image processing software such as Photoshop and ImageJ, we developed a convenient method for semi-automatic segmentation and cell counting on brain sections. A standard template for brain region segmentation was first obtained from the Paxinos and Franklin's mouse brain atlas. Photoshop was then used to transform the standard template semi-automatically into the space of brain sections, yielding masks of segmented brain regions. Finally, ImageJ was used to analyze the data in different brain regions. This method is useful for immunohistochemical and neuron distribution pattern analyses, as well as neural network labelling studies. The method does not require expensive commercial image analysis software, and is also easy to implement and use.

A new species of the genus Camellia (Theaceae), Camelliazijinica , discovered in the Danxia landscape from Guangdong Province, China, is characterized and illustrated. Phylogenetic analysis based on chloroplast genomes suggested its affinity with C.drupifera , C.oleifera and C.fluviatilis , however, it morphologically differs from all of the latter by leaf shape and size. Phonologically, it most closely resembles C.microphylla , but can be distinguished from the latter by its young branchlets glabrous (vs. densely pubescent), fewer bracteoles and sepals, diverse leaf shape, midvein raised slightly with sparsely pubescent or glabrous (vs. prominently with densely pubescent) and leaf adaxially matt (vs. vernicose) when dried. By morphological and molecular analyses, Camelliazijinica represented a distinct new species of C.sect.Paracamellia., Competing Interests: The authors have declared that no competing interests exist., (Min Lin, Qin-Liang Ye, Zhi-Jian Zhang, Wen-Bo Liao, Qiang Fan.)

Background: Paraquat (PQ) is an effective herbicide and is widely used in agricultural production, but PQ poisoning is frequently seen in humans with the lung as the target organ. Clinically pulmonary pathological changes are often used to predict the severity and prognosis of the patients. In this study, we observed the expression of heat shock protein 70 (HSP70) in rat lung after PQ poisoning and to investigate the therapeutic effects of ulinastatin., Methods: Seventy-two adult healthy SD rats were randomly divided into a control group (group A, n=24), a poisoning group (group B, n=24), and an ulinastatin group (group C, n=24). The rat models of acute PQ poisoning were established by intra-gastric administration of 80 mg/kg PQ to rats of groups B and C, and the rats of group C were intra-peritoneally injected with 100 000 IU/kg ulinastatin 30 minutes after poisoning. The expression of HSP70 in lung tissue was observed, and W/D and histopathological changes in the lung tissue were compared 12, 24, 48 and 72 hours after poisoning. The expression of HSP70 in the lung tissue was assayed by using RT-PCR. All quantitative data were processed with one-way analysis of variance to compare multiple sample means., Results: Compared to group A, the expression of HSP70 in the lung of rats in groups B and C increased significantly at all intervals (P<0.05). The pathological changes in lung tissue of rats with PQ poisoning included congestion, leukocytes infiltration and local hemorrhage, whereas those of group C were significantly lessened., Conclusion: Ulinastatin may ameliorate acute lung injury to some extent after PQ poisoning in rats by enhancing the expression of HSP70.

We show that human embryonic stem cell-derived dopaminergic neurons survived transplantation to the neurotoxin 6-hydroxydopamine-lesioned rat striatum and, in combination with the cells newly differentiated from their progenitors, contributed to locomotive function recovery at 5 months. The animal behavioral improvement was correlated with the dopamine neurons present in the graft. Although the donor cells contained forebrain and midbrain dopamine neurons, the dopamine neurons present in the graft mainly exhibited a midbrain, or nigra, phenotype, suggesting the importance of midbrain dopamine neurons in functional repair. Furthermore, progenies of grafted cells were neurons and glia with greatly diminished mitotic activity by 5 months. Thus, the in vitro-produced human dopamine neurons can functionally engraft in the brain.

Aim: To elucidate the localization of vasodilator stimulated phosphoprotein (VASP), a cytoskeletal organizing protein and a substrate of protein kinases A and G in mitotic gastric cancer cells., Methods: Immunofluorescence microscopy was used to observe the localization of alpha-tubulin, VASP and Ser157 phosphorylated VASP (p-VASP) in interphase of mitotic gastric cancer of the cell line SGC-7901., Results: Immunofluorescence staining showed that p-VASP but not VASP was co-localized with alpha-tubulin on spindle poles and fibers in prophase, metaphase and anaphase of the mitotic process of the gastric cancer cell line SGC-7901. H89, an inhibitor of protein kinases A and G, had no effect on the localization of p-VASP on the spindles., Conclusion: VASP may play a role in assembling and stabilizing the mitotic spindle of cells, and phosphorylation of the protein is the precondition for it to exert this function.