Global genetic diversity,lineage distribution,and Wolbachia infection of the alfalfa weevil Hypera postica (Coleoptera: Curculionidae)

The alfalfa weevil (Hypera postica) is a well‐known example of a worldwide‐distributed pest with high genetic variation. Based on the mitochondrial genes, the alfalfa weevil clusters into two main mitochondrial lineages. However, there is no clear picture of the global diversity and distribution of these lineages; neither the drivers of its diversification are known. However, it appears likely that historic demographic events including founder effects played a role. In addition, Wolbachia, a widespread intracellular parasite/symbiont, likely played an important role in the evolution of the species. Wolbachia infection so far was only detected in the Western lineage of H. postica with no information on the infecting strain, its frequency, and its consequences on the genetic diversity of the host. We here used a combination of mitochondrial and nuclear sequences of the host and sequence information on Wolbachia to document the distribution of strains and the degree of infection. The Eastern lineage has a higher genetic diversity and is found in the Mediterranean, the Middle East, Eastern Europe, and eastern America, whereas the less diverse Western lineage is found in Central Europe and the western America. Both lineages are infected with the same common strain of Wolbachia belonging to Supergroup B. Based on neutrality tests, selection tests, and the current distribution and diversification of Wolbachia in H. postica, we suggested the Wolbachia infection did not shape genetic diversity of the host. The introduced populations in the United States are generally genetically less diverse, which is in line with founder effects.     

Grazing intensity enhances spatial aggregation of dominant species in a desert steppe

Understanding how grazing activity drives plant community structure or the distribution of specific species in a community remains a major challenge in community ecology. The patchiness or spatial aggregation of specific species can be quantified by analyzing their relative coordinates in the community. Using variance and geostatistical analysis methods, we examined the quantitative characteristics and spatial distribution of Stipa breviflora in a desert steppe in northern China under four different grazing intensities (no grazing, NG, light grazing, LG, moderate grazing, MG, and heavy grazing, HG) at three small spatial scales (10 × 10 cm, 20 × 20 cm, 25 × 25 cm). We found that grazing significantly increased cover, density, and proportion in standing crop of S. breviflora, but decreased height. The spatial distribution of S. breviflora was strongly dependent upon the sampling unit and grazing intensity. The patchiness of S. breviflora reduced with sampling scale, and spatial distribution of S. breviflora was mainly determined by structural factors. The intact clusters of S. breviflora were more fragmented with increasing grazing intensity and offspring clusters spread out from the center of the parent plant. These findings suggest that spatial aggregation can enhance the ability of S. breviflora to tolerate grazing and that smaller isolated clusters are beneficial to the survival of this dominant species under heavy grazing.     

黄酒酿造原料及生产工艺研究现状与展望

黄酒的质量取决于酿造原料、酒曲、加工工艺以及酿造环境,不同的酿造原料、酒曲、加工工艺和环境能赋予黄酒不同的品质与风味。本文在检索文献、比较分析新旧版黄酒国标的基础上,介绍了南北地区黄酒酿造原料的差异以及新型功能性黄酒原辅料研发现状,综述了浸米、蒸饭与发酵三个工艺关键环节的最新研究进展,旨在为黄酒技术的创新,功能性、饮料性、国际性黄酒新产品开发提供借鉴及参考。     

Fasting-Mimicking Diet Modulates Microbiota and Promotes Intestinal Regeneration to Reduce Inflammatory Bowel Disease Pathology

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Plastid and nuclear phylogenomic incongruences and biogeographic implications of Magnolia s.l. (Magnoliaceae)

Magnoliaceae, an assemblage of early diverged angiosperms, comprises two subfamilies, speciose Magnolioideae with approximately 300 species in varying numbers of genera and monogeneric Liriodendroideae with two species in Liriodendron L. This family occupies a pivotal phylogenetic position with important insights into the diversification of early angiosperms, and shows intercontinentally disjunct distribution patterns between eastern Asia and the Americas. Widespread morphological homogeneity and slow substitution rates in Magnolia L. s.l. resulted in poorly supported phylogenetic relationships based on morphology or molecular evidence, which hampers our understanding of the genus’ temporal and spacial evolution. Here, based on the newly generated genome skimming data for 48 Magnolia s.l. species, we produced robust Magnolia phylogenies using genome-wide markers from both plastid genomes and single nucleotide polymorphism data. Contrasting the plastid and nuclear phylogenies revealed extensive cytonuclear conflicts in both shallow and deep relationships. ABBA-BABA and PhyloNet analyses suggested hybridization occurred within sect. Yulania, and sect. Magnolia, which is in concordance with the ploidy level of the species in these two sections. Divergence time estimates and biogeographic reconstruction indicated that the timing of the three tropical Magnolia disjunctions coincided with the mid-Eocene cooling climate and/or late Eocene climate deterioration, and two temperate disjunctions occurred much later, possibly during the warm periods of the Miocene, hence supporting the boreotropical flora concept of Magnolia s.l.     

Fullerene nanoparticles for the treatment of ulcerative colitis

Ulcerative colitis (UC) is a long-term, recurrent inflammatory bowel disease for which no effective cure is yet available in the clinical setting. Repairing the barrier dysfunction of the colon and reducing intestinal inflammation are considered key objectives to cure UC. Here we demonstrate a novel therapeutic strategy based on a C₆₀ fullerene suspension (C₆₀FS) to treat dinitrobenzene sulfonic acid-induced UC in an animal model. C₆₀FS can repair the barrier dysfunction of UC and effectively promote the healing of ulcers; it also manifests better treatment effects compared with mesalazine enema. C₆₀FS can reduce the numbers of basophils in the blood of UC rats and mast cells in the colorectal tissue, thereby effectively alleviating inflammation. The expression of H1R, H4R, and VEGFR2 receptors in colorectal tissues is inhibited by C₆₀FS, and the levels of histamine and prostaglandin in the rat blood are reduced. This work presents a reliable strategy based on fullerene to cure UC and provides a novel guide for UC treatment.

     

Genetically encoded redox biosensor system for H2O2 measurement in four subcellular compartments in acute myeloid leukemia (AML) cells

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Light from heat lamps affects sow behaviour and piglet salivary melatonin levels

The light environment regulates animal physiology and behaviour. As widely used supplementary heat sources in creep areas, the effect of visible light radiated by infrared heat lamps on pigs is worth investigating. To investigate the effects of light from heat lamps on the behaviour of sows and piglets and possible endocrine mechanisms, 24 primiparous sows were randomly assigned to three supplementary heat source treatments: (1) 250 W non-luminous ceramic heat lamps (CE, n = 8), (2) 175 W red heat lamps (RL, n = 8), and (3) 175 W transparent heat lamps (TL, n = 8). All heat lamps were turned off on Day 15 postpartum. Piglets were weighed on days 3 and 21 postpartum. The number and duration of suckling within 24 h were analysed via video recordings on days 4, 8, and 16 postpartum. Sow posture changes during the day and night were detected using the YOLOv4 target detection network model. One marked piglet from six litters randomly selected from each treatment was used for saliva collection. Saliva samples were collected at 0800, 1400, 2000, and 0200 (+1 d) on days 10 and 20 postpartum. The results showed that the mean postural change frequency of TL sows was higher than that of CE sows (P < 0.05), while that of RL sows was not different from that of CE and TL sows. However, the duration of the sows being in each posture was not affected by the treatment. The total suckling duration of TL piglets was significantly longer than that of CE piglets, but there was no significant difference in the performance of the piglets. The melatonin concentrations in the saliva of piglets at 10 and 20 days of age in the three treatments showed different diurnal rhythms, but there was no significant difference in the levels of melatonin in TL piglets between night and day. Differences in salivary cortisol levels only appeared between the CE and RL groups at 20 days of age. Based on the present results, the illuminance and spectrum of the transparent heat lamps were sufficient to stimulate sow activity and inhibit melatonin levels in piglets. However, the stimulating effect on suckling was not sufficient to significantly improve the performance of piglets. Exposure to red heat lamps, rather than ceramic lamps, resulted in the strongest circadian rhythm of salivary melatonin in piglets.     

Cryo-EM structures reveal the dynamic transformation of human alpha-2-macroglobulin working as a protease inhibitor

Science China Life Sciences - Human alpha-2-macroglobulin is a well-known inhibitor of a broad spectrum of proteases and plays important roles in immunity, inflammation, and infections. Here, we...