Effect of Yulangsan Polysaccharide on the Reinstatement of Morphine-Induced Conditioned Place Preference in Sprague–Dawley Rats

We previously reported that Yulangsan polysaccharide (YLSP), which was isolated from the root of Millettia pulchra Kurz, attenuates withdrawal symptoms of morphine dependence by regulating the nitric oxide pathway and modulating monoaminergic neurotransmitters. In this study, we investigated the effects and mechanism of YLSP on the reinstatement of morphine-induced conditioned place preference (CPP) in rats. A CPP procedure was employed to assess the behavior of rats, and indicators of serum and four brain regions (nucleus accumbens, ventral tegmental area, hippocampus and prefrontal cortex) were determined to explore its underlying mechanism. YLSP inhibited priming morphine-induced reinstatement of CPP in a dose-dependent manner. YLSP markedly reduced nitric oxide and nitric oxide synthase levels in the brain. Moreover, YLSP significantly decreased the dopamine and norepinephrine levels in the serum and brain. Furthermore, YLSP significantly decreased cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) concentrations, inhibited the expression of dopamine D1 receptors and cAMP response element binding protein mRNA, and improved the expression of dopamine D2 receptor mRNA in the four brain regions. Our findings indicated that YLSP could inhibit the reinstatement of morphine-induced CPP possibly by modulating the NO-cGMP and D1R-cAMP signaling pathways.     

Hyperbaric Oxygen Attenuates Withdrawal Symptoms by Regulating Monoaminergic Neurotransmitters and NO Signaling Pathway at Nucleus Accumbens in Morphine-Dependent Rats

In this study, we examined whether hyperbaric oxygen (HBO₂) plays a detoxification role in withdrawal symptoms in a morphine-dependent rat model. The model was established through injections of morphine at increasing doses for 7 days. Withdrawal symptoms were induced by naloxone injection on the 8th day. The detoxification effect of HBO₂ was evaluated using the withdrawal symptom scores, biochemical indices and neurotransmitters. Compared with the model group, HBO₂ therapy significantly attenuated the withdrawal symptom scores, body weight loss and the level of norepinephrine level, whereas it increased the dopamine level and tyrosine hydroxylase expression in the nucleus accumbens. Moreover, HBO₂ therapy substantially alleviated the NO, NOS, cAMP, and cGMP levels. Our findings indicate that HBO₂ can effectively alleviate withdrawal symptoms induced by morphine dependence, and these effects may be attributed to the modulation of monoaminergic neurotransmitters and the suppression of the NO–cGMP signaling pathway.     

The first baleen whale marine protected area proposed for Bryde's whales in the Beibu Gulf,China

The establishment of marine protected areas (MPAs) for cetaceans is an important strategy to mitigate human disturbance and protect biodiversity. Despite abundant cetacean species, there are only a few MPAs dedicated to cetacean conservation in China, all of which are for inshore dolphins. Bryde's whales, the only nearshore baleen whale population in mainland China, are conflicting with intensive human activities, yet an effective conservation strategy is lacking. This study used species distribution models to analyze distribution patterns and suitable habitats of Bryde's whales in the Beibu Gulf and proposes the first baleen whale MPA in China. Our results showed Bryde's whales have a seasonal distribution pattern in the Beibu Gulf, and that the waters around Weizhou Island and the southeastern coast of Vietnam were their core habitats. The seasonal nighttime light data indicated a negative relationship between the number of ship lights and Bryde's whale sightings and suggest that Bryde's whales might be threatened by fisheries. We proposed an MPA based on the results, suggesting that the waters within 20 km around Weizhou Island should be declared a protected area. Furthermore, we recommend that anthropogenic activities in the waters around Weizhou Island are better managed to reduce negative impacts on marine life.     

New Furanone Derivatives and Alkaloids from the Co‐Culture of Marine‐Derived Fungi Aspergillus sclerotiorum and Penicillium citrinum

Six new compounds including two furanone derivatives sclerotiorumins A and B ( 1 and 2 ), one novel oxadiazin derivative sclerotiorumin C ( 3 ), one pyrrole derivative 1‐(4‐benzyl‐1H‐pyrrol‐3‐yl)ethanone ( 4 ), and two complexes of neoaspergillic acid aluminiumneohydroxyaspergillin ( 5 ) and ferrineohydroxyaspergillin ( 6 ) were isolated from the co‐culture of marine‐derived fungi Aspergillus sclerotiorum and Penicillium citrinum. Compound 3 was the first natural 1,2,4‐oxadiazin‐6‐one. Compound 5 showed significant and selective cytotoxicity against human histiocytic lymphoma U937 cell line (IC₅₀ = 4.2 μm ) and strong toxicity towards brine shrimp (LC₅₀ = 6.1 μm ), and oppositely increased the growth and biofilm formation of Staphylococcus aureus.     

水稻糯性相关基因的全基因组关联分析

利用1 090 071个SNP标记, 对419份广西地方稻种资源核心种质的糯性进行全基因组关联分析。结果表明, 运用混合线性模型, 在P<4.72×10^-8 (4.72E-8)水平下, 检测到45个与糯性显著关联的SNP位点, 均位于第6号染色体上。通过筛选显著关联位点上、下游各150 kb区域内的基因, 共找到305个候选基因, 其中包含2个与淀粉合成酶相关的Wx和SSIIa基因; 同时在第6号染色体5.69-5.89 Mb区域发现4个与糯性显著关联的SNP位点, 该区域可能是影响水稻(Oryza sativa)糯性的重要候选区域。     

Chromosome changes after polyploidization in Triticeae

Chromosome changes are common in Triticeae, and they occur widely in natural and resynthesized polyploidy. Two important factors, nucleocytoplasmic interaction (internal) and the environment (external), can significantly influence chromosome changes after polyploidization. And chromosomal DNA changes play key roles during the initial formation, gradual stabilization, and establishment of polyploids. Hybrid breeding between common wheat and related wild species of Triticeae is an example of polyploidization, and many of the chromosome changes occurring after hybridization could be useful for improving wheat varieties. The famous chromosomal translocation 1BL/1RS that occurred after ancestral hybridization between wheat and rye is distributed widely among modern wheat varieties and makes a big contribution to wheat breeding; xiaoyan 6 is a similarly distant hybridization between wheat and Agropyron elongatum (Host) P. Beauv. in China. This chromosome translocation line was cultivated as the main variety in Shaanxi Province for 16 years and has also been used as a core parent for wheat breeding in China during the past 20 years because of its outstanding merits.     

Production of hyperthermostable GH10 xylanase Xyl10B from Thermotoga maritima in transplastomic plants enables complete hydrolysis of methylglucuronoxylan to fermentable sugars for biofuel production

Overcoming the recalcitrance in lignocellulosic biomass for efficient hydrolysis of the polysaccharides cellulose and hemicellulose to fermentable sugars is a research priority for the transition from a fossilfuel-based economy to a renewable carbohydrate economy. Methylglucuronoxylans (MeGXn) are the major components of hemicellulose in woody biofuel crops. Here, we describe efficient production of the GH10 xylanase Xyl10B from Thermotoga maritima in transplastomic plants and demonstrate exceptional stability and catalytic activities of the in planta produced enzyme. Fully expanded leaves from homotransplastomic plants contained enzymatically active Xyl10B at a level of 11-15% of their total soluble protein. Transplastomic plants and their seed progeny were morphologically indistinguishable from non-transgenic plants. Catalytic activity of in planta produced Xyl10B was detected with poplar, sweetgum and birchwood xylan substrates following incubation between 40 and 90 °C and was also stable in dry and stored leaves. Optimal yields of Xyl10B were obtained from dry leaves if crude protein extraction was performed at 85 °C. The transplastomic plant derived Xyl10B showed exceptional catalytic activity and enabled the complete hydrolysis of MeGXn to fermentable sugars with the help of a single accessory enzyme (α-glucuronidase) as revealed by the sugar release assay. Even without this accessory enzyme, the majority of MeGXn was hydrolyzed by the transplastomic plant-derived Xyl10B to fermentable xylose and xylobiose.