114 research outputs found

    Transcriptome Analysis of the Brown Planthopper Nilaparvata lugens

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    BACKGROUND: The brown planthopper (BPH) Nilaparvata lugens (Stål) is one of the most serious insect pests of rice in Asia. However, little is known about the mechanisms responsible for the development, wing dimorphism and sex difference in this species. Genomic information for BPH is currently unavailable, and, therefore, transcriptome and expression profiling data for this species are needed as an important resource to better understand the biological mechanisms of BPH. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we performed de novo transcriptome assembly and gene expression analysis using short-read sequencing technology (Illumina) combined with a tag-based digital gene expression (DGE) system. The transcriptome analysis assembles the gene information for different developmental stages, sexes and wing forms of BPH. In addition, we constructed six DGE libraries: eggs, second instar nymphs, fifth instar nymphs, brachypterous female adults, macropterous female adults and macropterous male adults. Illumina sequencing revealed 85,526 unigenes, including 13,102 clusters and 72,424 singletons. Transcriptome sequences larger than 350 bp were subjected to Gene Orthology (GO) and KEGG Orthology (KO) annotations. To analyze the DGE profiling, we mainly compared the gene expression variations between eggs and second instar nymphs; second and fifth instar nymphs; fifth instar nymphs and three types of adults; brachypterous and macropterous female adults as well as macropterous female and male adults. Thousands of genes showed significantly different expression levels based on the various comparisons. And we randomly selected some genes to confirm their altered expression levels by quantitative real-time PCR (qRT-PCR). CONCLUSIONS/SIGNIFICANCE: The obtained BPH transcriptome and DGE profiling data provide comprehensive gene expression information at the transcriptional level that could facilitate our understanding of the molecular mechanisms from various physiological aspects including development, wing dimorphism and sex difference in BPH

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Changes of brain activation and networks in patients with spinal cord injury based on functional near⁃infrared spectroscopy

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    Objective To investigate the changes of brain activation and brain network connectivity in patients with spinal cord injury (SCI). Methods A total of 20 patients with SCI were selected from Qilu Hospital of Shandong University from January to October 2021, including 8 patients with simple lower extremity involvement (paraplegia group) and 12 patients with all limbs involvement (tetraplegia group), and 10 healthy controls with matched baseline data with the SCI group were included in the same period. Functional near⁃infrared spectroscopy (fNIRS) was used to collect the data of cerebral oxyhemoglobin (HbO2) in the bilateral prefrontal lobe (LPFC/RPFC), motor cortex (LMC/RMC) and occipital lobe (LOL/ROL). The resting HbO2 β values was calculated by generalized linear model to evaluate the activation degree of the cerebral cortex covered by different detection channels, the correlation between HbO2 β values was calculated by Pearson correlation analysis and partial correlation to analysis different detection channels [partial correlation coefficient (r) was defined as functional connectivity strength] to evaluate the functional connectivity of the brain network. Results 1) Degree of brain activation: compared with the control group, the HbO2 β values corresponding to channel 2 (t=⁃2.482, P=0.020), channel 8 (t=⁃3.315, P=0.003) and channel 16 (t=⁃2.738, P=0.011) was increased in the tetraplegia group, while the HbO2 β value corresponding to channel 25 was decreased (t=2.104, P=0.045), and the HbO2 β value of channel 8 was increased (t=⁃2.475, P=0.020) in paraplegia group. Compared with the tetraplegia group, the HbO2 β values in channel 17 (t=2.552, P=0.017) and channel 25 (t=2.342, P=0.027) were increased in the paraplegia group. The value of HbO2 β in the left prefrontal lobe of tetraplegia group was significantly higher than that of control group (t=2.652, P=0.013). 2) The number of functional connections between different channels and cerebral cortex: the proportion of channels related to motor cortex in different groups was 94.12% in the paraplegia group (32/34), 82.76% in the tetraplegia group (24/29), and only 74.36% in the control group (29/39). 3) Functional connectivity strength in the brain: compared with the control group, the functional connectivity strength in the right motor area was weakened in both the paraplegia group (t=4.572, P=0.000) and the tetraplegia group (t=4.822, P=0.000). Conclusions There are abnormalities in resting brain activation and functional connectivity of brain network after SCI, which are manifested as local enhancement of spontaneous neural activity in some brain regions and abnormal functional connectivity in cerebral cortices and brain regions

    Biocatalytic Upgrading of 5‑Hydroxymethylfurfural (HMF) with Levulinic Acid to HMF Levulinate in Biomass-Derived Solvents

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    Valorization of biomass-based platform chemicals into high value-added products has attracted increasing attention recently. In this work, upgrading of 5-hydroxymethylfurfual (HMF) and levulinic acid, two important biomass-based platform chemicals, to HMF levulinate via a green and efficient enzymatic approach was reported. Novozym 435 was found to be the best biocatalyst for the enzymatic esterification. The enzymatic esterification progressed smoothly in <i>t</i>-butanol, 2-methyl-2-butanol, and cyclopentyl methyl ether as well as in the ecofriendly biomass-derived 2-methyltetrahydrofuran (2-MeTHF), while no enzymatic reaction occurred in deep eutectic solvents. When HMF concentration was up to 500 mM, a good conversion of 72% was achieved in 2-MeTHF. The reaction temperature exerted a significant effect on the enzymatic esterification. When the reaction temperature is below 40 °C, high HMF conversions (>85%) were obtained. Besides, significant inactivation of the enzyme was observed at more than 50 °C, resulting in poor conversions
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