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Modified polyglycolic acid (PGA) was prepared by melt blending and reactive extrusion. The effects of chain extenders, crosslinking agents and lubricants on melt fluidity, dynamic rheological properties, thermal stability, and crystallization properties of modified samples were studied. The results show that the melt strength of samples are significantly improved by using ADR chain extender and BIBP crosslinking agent simultaneously, the melt mass flow rate is decreased by 73.6% compared to pure PGA. The thermal stability of modified samples is also improved, with increasing the 5% thermal decomposition temperature by 7 °C. With the addition of chain extender and crosslinking agent, the degree of crystallinity of PGA samples are decreased, the number of crystal nuclei are decreased, and the spherulite size are increased. The degree of cross-linking of the sapmles with adding chain extender and crosslinking agent at the same time is increased, resulting in imperfect crystallization and the formation of irregular crystals. Molecular motion are promoted by lubricants, and the crystallization temperature of PGA sample is decreased from 179.3 °C without addition to 173.9 °C after addition. [ABSTRACT FROM AUTHOR]

Aims: To investigate effects of repetitive transcranial magnetic stimulation (rTMS) on the prospective memory (PM) in patients with schizophrenia (SCZ). Methods: Fifty of 71 patients completed this double‐blind placebo‐controlled randomized trial and compared with 18 healthy controls' (HCs) PM outcomes. Bilateral 20 Hz rTMS to the dorsolateral prefrontal cortex at 90% RMT administered 5 weekdays for 4 weeks for a total of 20 treatments. The Positive and Negative Symptom Scale (PANSS), the Scale for the Assessment of Negative Symptoms (SANS), and PM test were assessed before and after treatment. Results: Both Event‐based PM (EBPM) and Time‐based PM (TBPM) scores at baseline were significantly lower in patients with SCZ than that in HCs. After rTMS treatments, the scores of EBPM in patients with SCZ was significantly improved and had no differences from that in HCs, while the scores of TBPM did not improved. The negative symptom scores on PANSS and the scores of almost all subscales and total scores of SANS were significantly improved in both groups. Conclusions: Our findings indicated that bilateral high‐frequency rTMS treatment can alleviate EBPM but not TBPM in patients with SCZ, as well as improve the negative symptoms. Significance: Our results provide one therapeutic option for PM in patients with SCZ. [ABSTRACT FROM AUTHOR]

The chemical epigenetic modifier 5-azacitidine (5-Aza C), a DNA methyltransferase inhibitor, was used to manipulate the endophytic fungus Penicillium sp. KMU18029. From its rice fermentation extract, a new polyketone compound (3S,4R)-3,4,8-trihydroxy-6-methyl-3,4-dihydronaphthalen-1(2H)-one (1), along with 13 known compounds, 3,4,8-trihydroxy-6-(hydroxymethyl)-3,4-dihydronaphthalen-1(2H)-one (2), decaturin B (3), 15-hydroxydecaturin A (4), oxalicine A (5), pileotin A (6), pyrandecarurin A (7), decaturenol A (8), decaturenoid (9), penisarins A (10), oxaline (11), (4E,8E)-N-D-2'-hydroxyocta-decanoyl-1-O-β-D-glycopy-ranosyl-9-methyl-4,8-sphingadienine (12), ergosterol (13) and stigma-5-en-3-O-β-glucoside (14), were separated. Among the known compounds, 2, 7, 12 and 14 were not found in our previous research on this strain. The structure of the new compound was identified by spectroscopic techniques such as HR-ESIMS, 1D NMR, 2D NMR and CD. Furthermore, all the isolated compounds were tested for their antimicrobial activities, and only compounds 1, 2 and 11 showed weak activities against S. aureus, with MICs of 128 μg/mL. [ABSTRACT FROM AUTHOR]

Summary: Rotylenchus astragalus sp. n. is characterised by having females 841-1069 μ m long, stylet 28-31 μ m long, basal knobs rounded, dorsal pharyngeal gland orifice (DGO) 3-5 μ m, lateral field with four incisures, pharyngeal gland lobes slender, overlapping intestine dorsally for 4-12 μ m, excretory pore located just posterior to the hemizonid, vulva slightly posterior to mid-body, ovaries paired, phasmid opening relatively large and 8-18 annuli anterior to the anus, tail conoid and absence of males. The matrix code of R. astragalus sp. n. is A5, B3, C1, D4, E1, F2, G1-2, H3, I2, J2, K1. In addition, phylogenetic relationships of the recovered populations were analysed using sequences of the near full length small subunit (SSU) and D2-D3 segments of large subunit (LSU) rRNA genes. [ABSTRACT FROM AUTHOR]

Nine diterpenoid alkaloids were isolated from Aconitum georgei Comber belonging to the genus Aconitum in Ranunculaceae family. Their structures were determinated by using HR-ESI-MS and 1 D/2D NMR spectra as geordine (1), yunaconitine (2), chasmanine (3), crassicauline A (4), forestine (5), pseudaconine (6), 14-acetylalatisamine (7), austroconitine B (8), and talatisamine (9). Among them, compound 1 is a previously undescribed aconitine-type C19-diterpenoid alkaloid, and compounds 3, and 5-9 have not previously been isolated from this species. The results of in vitro experiments indicated that new compound 1 possesses mild anti-inflammatory activity, which inhibited the production of NO in LPS-activated RAW 264.7 cells with an inhibition ratio of 29.75% at 50 μM. [ABSTRACT FROM AUTHOR]

The emergence of biodegradable polymers has brought hope for solving the problem of plastic pollution. Chemical recovery of biodegradable polymers not only avoids CO2 emissions from polyester degradation, but also enables sustainable utilization of feedstocks. In this study, biodegradable PGA-PBC-PGA triblock copolymers with chemical recovery characteristics were synthesized using ring-opening polymerization (ROP) of glycolide (GL). The Tonset of the triblock copolymers was higher than 315 °C. Mechanical tests showed that the tensile strengths of the copolymers were in the range of 27.5–98.2 MPa, and the elongations at break were in the range of 9.2–409%. The gas permeation test showed that the triblock copolymers had excellent O2 and CO2 barrier performance, which was better than PBS, PBAT and PLA. Besides, the triblock copolymers have excellent degradation properties under both enzymatic and non-enzymatic conditions. What's more, the triblock copolymers were allowed to recover GL by thermal depolymerization. Among them, PGA-PBC-PGA60 could recover GL in 82% yield at 240 °C in 3 hours. The recovered GL could be reused for the next polymerization after recrystallization and purification. The performances of the copolymers after re-polymerization were comparable to that of the original copolymer, successfully completing the closed-loop process from a monomer to a polymer and then to a monomer. [ABSTRACT FROM AUTHOR]