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Chemically synthesized poly(4-hydroxybutyrate) (P4HB) is a new generation of biomass-derived and degradable semi-crystalline polymer with good comprehensive properties, but high costs limit its application. Starch, as an inexpensive natural polymer, can reduce the cost of P4HB products. However, starch lacks thermoplastic behavior and has poor compatibility with P4HB, thus its extensive use will inevitably impair the mechanical properties of P4HB. In this study, the ball-milling starch grafting process is adopted, which can simultaneously solve the two major deficiencies of starch, and the prepared ball-milling starch-g-polycaprolactone (BSt-g-PCL) has thermoplasticity and better compatibility with P4HB. BSt-g-PCL can melt near 55 °C, and the interweaving of its molecular chains with P4HB reduces the binding energy (Einteraction) of both, making the phase interface blurred or even disappear. Therefore, the elongation at break retention (REB) of P4HB/BSt-g-PCL can increase from 37.1 % to 74.3 % compared to P4HB/starch at the same filling (70 Phr). Additionally, BSt-g-PCL can exert the effect of accelerating P4HB degradation and still make it maintain excellent anti-aging ability. The ball-milling starch graft process provides a simple and effective method for the preparation of inexpensive fully biodegradable P4HB composite films with excellent mechanical properties.

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The Pestalotiopsis sp. strain cr013 is a mycoparasite of Cronartium ribicola, a potential biocontrol fungus for Armand pine (Pinus armandii) blister rust. A previous study showed that the strain cr013 has great potential to produce new compounds. However, there has been no report of the whole-genome sequence of the mycoparasite Pestalotiopsis sp. In this study, the BGISEQ-500 and Oxford Nanopore GridION X5 sequencing platforms were used to sequence the strain cr013 isolates and assemble the reads to obtain the complete genome. We first report the whole-genome information of the mycoparasite Pestalotiopsis sp. strain cr013 (GenBank accession number: JACFXT010000000, BioProject ID: PRJNA647543, BioSample ID: SAMN15589943), and the genomic components and gene functions related to the mycoparasitism process were analyzed. This study provides a theoretical basis for understanding the lifestyle strategy of the mycoparasite Pestalotiopsis sp. and reveals the mechanisms underlying secondary metabolite diversity in the strain cr013.

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OBJECTIVE: To observe the effect of electroacupuncture(EA) on neural function and spinal cord pathological morphology in spinal cord injury(SCI) mice and investigate the anti-inflammatory molecular mechanism of EA on SCI mice from the aspects of gene by using bioinformatics. METHODS: Seventy-two female C57BL/6 mice were randomized into sham operation, model and EA groups, with 24 mice in each group. The SCI model was established by clamping the spinal cord with a serrefine after laminectomy at the 1st lumbar vertebra(L1). EA(1.5 Hz/7.5 Hz, 1.0 mA) was applied to bilateral "Jiaji"(EX-B2) and "Zusanli"(ST36) for 10 min, once a day for 14 consecutive days. Basso Mouse Scale(BMS) score was used to assess the hindlimb locomotor function of mice. Histopathological changes of the injured area of the spinal cord were determined by HE staining. The spinal cord RNA was sequenced by using RNA-Seq technology. The bioinformatic analysis was then performed to detect the diffe-rential genes between groups, and the function classification and the involved pathways were enriched. The mRNA and protein expressions of differential genes were detected and verified by using qRT-PCR and Western blot. RESULTS: Compared with the sham operation group, BMS score of the model group was significantly decreased(P<0.05), while that of EA group was increased relevant to the model group (P<0.05). HE staining showed loose and disordered structure and arrangement, cavitation, more inflammatory infiltration, nucleus pycnosis, and neuronal necrosis in the model group, which was alleviated in the EA group. Compared with the sham operation group, 565 differential genes were detected in the model group, including 545 up-regulated and 20 down-regulated, while 41 were detected between the EA and the model group, including 2 up-regulated and 39 down-regulated in the EA group. Fifteen genes that were all up-regulated after modeling and down-regulated after EA intervention were detected by using Venn plot, which are Retn, Adipoq, Myh1, Actn2, Pck1, Klhl41, Fabp4, Hspb7, Myot, Ankrd2, Hrc, Cox6a2, Obscn, Col2a1, Mybpc1, and 3 inflammation-related genes(Fabp4, Adipoq and Pck1) were finally acquired. The 15 differential genes were annotated into main biological processes, cell composition and molecular function in the GO function classification analysis. The 15 differential genes were then enriched into different KEGG pathways, including the peroxisome proliferatorsactivated receptor (PPAR) signaling pathway, Adipocytokine signaling pathway. The mRNA and protein expressions of Fabp4, Adipoq and Pck1 in spinal cord detected by qRT-PCR and Western blot were significantly increased in the model group (P<0.001, P<0.01), while these were significantly decreased in the EA group relevant to the model group(P<0.001, P<0.01, P<0.05). CONCLUSION: EA can promote the repair of nerve function and improve inflammatory infiltration in SCI mice. The mechanism may be closely related to the down-regulation of inflammatory factors Fabp4, Adipoq and Pck1 expression, and the regulation of PPAR and Adipocytokine signaling pathways.

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Cerebral infarction (CI) is one of the most common cerebrovascular diseases and remains a major health problem worldwide. In this study, we evaluated the potential diagnostic biomarkers and important relevant metabolic pathways associated with CI. Metabolomics based on gas chromatography-mass spectrometry coupled with the multivariate pattern recognition technique were used to characterize the potential serum metabolic profiles of CI. Forty healthy controls and thirty-three cerebral infarction patients were recruited for the nontargeted global metabolites' study and subsequent targeted fatty acid analysis. Overall, thirty-four endogenous metabolites were found in serum from the untargeted global study, four of which were detected to be significantly different between the CI group and healthy controls, including l-lysine, octadecanoic acid (fatty acid), l-tyrosine and lactic acid. Additionally, fourteen free fatty acids were identified by the subsequent targeted fatty acid analysis, and seven of them were detected to be significantly different between the CI group and healthy controls, which were mainly associated with arachidonic acid metabolism and fatty acid metabolism. Our results suggest several potential diagnostic biomarkers, and serum metabolism research is demonstrated as a powerful tool to explore the pathogenesis of CI.