Effects of selenium adaptation on intestinal morphology, antioxidant-relate genes expression and intestinal microflora of grass carp (Ctenopharyngodon idella)

In the study, the effects of selenium on intestinal tissue morphology, antioxidant-related genes, and intestinal flora of grass carp (Ctenopharyngodon idella) were studied. For this purpose, 180 healthy grass carps (20.0±2.0 g) were randomly divided into three groups with three replicates each: the corresponding amount of anhydrous sodium selenite was added to make experimental water solutions of different concentrations, including 0 μg/L Se4+ (control group), 200 μg/L Se4+ group and 300 μg/L Se4+ group. The experiment was carried out for 42 days. The obtained results showed that: at the end of the experiment, the 200 μg/L Se4+ adaptation can have beneficial effects on the intestinal villi height and goblet cells. The CuZnSOD and CAT genes mRNA levels of grass carp intestine were strongly upregulated in the 200ug/L Se4+ group. 200ug/L selenium could increase the expression level of the Hsp70 gene in the intestinal tract of grass carp after 42 days of adaptation. At the genus level, the most abundant sequence in the gut of Se-treated grass carp was Pseudomonas, while Aeromon, Flavobacterium, and Defluviimonas were more abundant in the control group. In conclusion, this study demonstrates that 200ug/L Se4+ selenium adaptation can positively affect gut morphology and antioxidant responses and can alter the gut microbiota structure of grass carp. The results will provide a theoretical basis for further research on the effect of selenium on aquatic animals

Epilepsy phenotype and response to KCNQ openers in mice harboring the Kcnq2 R207W voltage-sensor mutation

KCNQ2-encoded Kv7.2 subunits play a critical role in balancing neuronal excitability. Mutations in KCNQ2 are responsible for highly-heterogenous epileptic and neurodevelopmental phenotypes ranging from self-limited familial neonatal epilepsy (SeLFNE) to severe developmental and epileptic encephalopathy (DEE). Pathogenic KCNQ2 variants cluster at the voltage sensor domain (VSD), the pore domain, and the C-terminal tail. Although several knock-in mice harboring Kcnq2 pore variants have been developed, no mouse line carrying Kcnq2 voltage-sensor mutations has been described. KCNQ2-R207W is an epilepsy-causing mutation located in the VSD, mainly affecting voltage-dependent channel gating. To study the physiological consequence of Kcnq2 VSD dysfunction, we generated a Kcnq2-R207W mouse line and analyzed the pathological and pharmacological phenotypes of mutant mice. As a result, both homozygous (Kcnq2RW/RW) and heterozygous (Kcnq2RW/+) mice were viable. While Kcnq2RW/RW mice displayed a short lifespan, growth retardation, and spontaneous seizures, Kcnq2RW/+ mice survived and developed normally, although only a fraction (9/64; 14%) of them showed behavioral- and ECoG-confirmed spontaneous seizures. Kcnq2RW/+ mice displayed increased susceptibility to evoked seizures, which was dramatically ameliorated by treatment with the novel KCNQ opener pynegabine (HN37). Our results show that the Kcnq2-R207W mouse line, the first harboring a Kcnq2 voltage-sensor mutation, exhibits a unique epileptic phenotype with both spontaneous seizures and increased susceptibility to evoked seizures. In Kcnq2-R207W mice, the potent KCNQ opener HN37, currently in clinical phase I, shows strong anticonvulsant activity, suggesting it may represent a valuable option for the severe phenotypes of KCNQ2-related epilepsy

A New Technological Analysis of Hoabinhian Stone Artifacts from Vietnam and its Implications for Cultural Homogeneity and Variability between Mainland Southeast Asia and South China

The cultural or technological variability and homogeneity of lithic industries during the transition from the Late Pleistocene to the Holocene in mainland Southeast Asia (SEA) and South China have yet to be clearly deciphered. Using typology as the main method and criterion for comparing lithic industries has failed to reveal either the character of lithic industries or their homogeneity and variability on a regional scale. This article presents a new technological analysis of Hoabinhian stone artifacts preserved in the Museum of Anthropology at the University of Social Sciences and Humanities, Vietnam National University, Hanoi and compares it with a typical Hoabinhian techno-complex from Laang Spean Cave in Cambodia and a representative cobble-tool industry from Luobidong on Hainan Island, South China. The comparisons suggest that remarkable differences in operational sequence existed not only between South China and the Hoabinhian of SEA, but also between different Hoabinhian assemblages of SEA. This study thus represents an important step forward for deciphering the homogeneity and variability of lithic industries on the larger regional scale of SEA and South China

Behavioral evidence for a magnetic sense in the oriental armyworm, Mythimna separata

Progress has been made in understanding the mechanisms underlying directional navigation in migratory insects, yet the magnetic compass involved has not been fully elucidated. Here we developed a flight simulation system to study the flight directionality of the migratory armyworm Mythimna separata in response to magnetic fields. Armyworm moths were exposed to either a 500 nT extreme weak magnetic field, 1.8 T strong magnetic field, or a deflecting magnetic field and subjected to tethered flight trials indoors in the dark. The moths were disoriented in the extreme weak magnetic field, with flight vectors that were more dispersed (variance=0.60) than in the geomagnetic field (variance=0.32). After exposure to a 1.8 T strong magnetic field, the mean flight vectors were shifted by about 105° in comparison with those in the geomagnetic field. In the deflecting magnetic field, the flight directions varied with the direction of the magnetic field, and also pointed to the same direction of the magnetic field. In the south-north magnetic field and the east-west field, the flight angles were determined to be 98.9° and 166.3°, respectively, and formed the included angles of 12.66° or 6.19° to the corresponding magnetic direction. The armyworm moths responded to the change of the intensity and direction of magnetic fields. Such results provide initial indications of the moth reliance on a magnetic compass. The findings support the hypothesis of a magnetic sense used for flight orientation in the armyworm Mythimna separata

Enterococcus casseliflavus regulates amino acid metabolism in edible insect Clanis bilineata tsingtauica: a functional metagenomics study

IntroductionThe soybean hawkmoth, Clanis bilineata tsingtauica, is an edible insect that possesses high nutritional, medicinal and economic value. It has developed into a characteristic agricultural industry in China.MethodsThe dominant gut bacterium in diapause larvae of soybean hawkmoths was identified by metagenomics, and the effect of diapause time on gut microbiome composition, diversity and function was investigated.ResultsEnterococcus and Enterobacter were measured to be the dominant genera, with Enterococcus casseliflavus and Enterococcus pernyi being the dominant species. Compared to the controls, the relative abundance of E. casseliflavus and E. pernyi on day 14 was lower by 54.51 and 42.45%, respectively. However, the species richness (including the index of Chao and ACE) of gut microbiota increased on day 28 compared to controls. The gene function was mainly focused on carbohydrate and amino acid metabolism. Metabolic pathways annotated for amino acids on day 14 increased by 9.83% compared to controls. It is speculated that diapause soybean hawkmoths may up-regulate amino acid metabolism by reducing E. casseliflavus abundance to maintain their nutritional balance. Additionally, tetracycline, chloromycetin and ampicillin were screened as the top three antibiotics against E. casseliflavus.DiscussionThis study not only extends our knowledge of gut microbiome in soybean hawkmoths at the species level, but also provides an initial investigation of gene functionality in interaction with insect hosts

Massive seasonal high-altitude migrations of nocturnal insects above the agricultural plains of East China

High-altitude, windborne movements of insects occur on an enormous scale, and have significant impacts on ecosystem function, provision of beneficial services, disease spread, and agricultural productivity. We used a combination of insect monitoring radar, balloon-borne nets, and searchlight traps to characterize the intensity, taxonomic composition, direction, and geographical extent of nocturnal insect “bioflows” occurring at heights to ~1 km above the agricultural lands of East China during spring, summer, and fall. We demonstrate seasonal northward and southward flows and show that the transport of insect biomass is considerably greater above this globally important food-production region than above the United Kingdom (the only other region where it has been quantified to date) and is dominated by species that are agricultural pests. Long-distance migrations of insects contribute to ecosystem functioning but also have important economic impacts when the migrants are pests or provide ecosystem services. We combined radar monitoring, aerial sampling, and searchlight trapping, to quantify the annual pattern of nocturnal insect migration above the densely populated agricultural lands of East China. A total of ~9.3 trillion nocturnal insect migrants (15,000 t of biomass), predominantly Lepidoptera, Hemiptera, and Diptera, including many crop pests and disease vectors, fly at heights up to 1 km above this 600 km-wide region every year. Larger migrants (>10 mg) exhibited seasonal reversal of movement directions, comprising northward expansion during spring and summer, followed by southward movements during fall. This north–south transfer was not balanced, however, with southward movement in fall 0.66× that of northward movement in spring and summer. Spring and summer migrations were strongest when the wind had a northward component, while in fall, stronger movements occurred on winds that allowed movement with a southward component; heading directions of larger insects were generally close to the track direction. These findings indicate adaptations leading to movement in seasonally favorable directions. We compare our results from China with similar studies in Europe and North America and conclude that ecological patterns and behavioral adaptations are similar across the Northern Hemisphere. The predominance of pests among these nocturnal migrants has severe implications for food security and grower prosperity throughout this heavily populated region, and knowledge of their migrations is potentially valuable for forecasting pest impacts and planning timely management actions

Soliton solution, breather solution and rational wave solution for a generalized nonlinear Schrödinger equation with Darboux transformation

Abstract In this paper, the exact solutions of generalized nonlinear Schrödinger (GNLS) equation are obtained by using Darboux transformation(DT). We derive some expressions of the 1-solitons, 2-solitons and n-soliton solutions of the GNLS equation via constructing special Lax pairs. And we choose different seed solutions and solve the GNLS equation to obtain the soliton solutions, breather solutions and rational wave solutions. Based on these obtained solutions, we consider the elastic interactions and dynamics between two solitons