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1.
目的:研究不同干燥方法对桂枝药材中苯丙素类(香豆素、肉桂醇、肉桂酸、桂皮醛、邻甲氧基肉桂醛)化学成分的影响,为桂枝适宜干燥方法的确定提供依据。方法:以苯丙素类化学成分含量为评价指标,分别对晒干、阴干及3种现代加工干燥方法后桂枝的质量进行评价,通过SPSS软件进行主成分分析,利用主成分得分进行综合评价。结果:不同干燥处理方法后有效成分含量差异较大,其中微波干燥使有效成分损失最多,阴干、晒干、低温热风干燥有利于桂枝有效成分的保留。结论:以干燥时间、化学成分含量、外观性状、气味等为评价指标,确定热风干燥50℃为桂枝药材较为适宜的现代干燥加工方法。  相似文献   
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Acetylation is an important, reversible posttranslational modification to a protein. In a previous study, we found that there were a large number of acetylated sites in various nutrient storage proteins of the silkworm haemolymph. In this study, we confirmed that acetylation can affect the stability of nutrient storage protein Bombyx mori apolipophorin‐III (BmApoLp‐III). First, the expression of BmApoLp‐III could be upregulated when BmN cells were treated with the deacetylase inhibitor panobinostat (LBH589); similarly, the expression was downregulated when the cells were treated with the acetylase inhibitor C646. Furthermore, the increase in acetylation by LBH589 could inhibit the degradation and improve the accumulation of BmApoLp‐III in BmN cells treated with cycloheximide and MG132 respectively. Moreover, we found that an increase in acetylation could decrease the ubiquitination of BmApoLp‐III and vice versa; therefore, we predicted that acetylation could improve the stability of BmApoLp‐III by competing for ubiquitination and inhibiting the protein degradation pathway mediated by ubiquitin. Additionally, BmApoLp‐III had an antiapoptosis function that increased after LBH589 treatment, which might have been due to the improved protein stability after acetylation. These results have laid the foundation for further study on the mechanism of acetylation in regulating the storage and utilization of silkworm nutrition.  相似文献   
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Diapause represents a major developmental switch in insects and is a seasonal adaptation that evolved as a specific subtype of dormancy in most insect species to ensure survival under unfavorable environmental conditions and synchronize populations. However, the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration in morphological, physiological, behavioral, and reproductive responses remains unclear. In the bivoltine strain of the silkworm Bombyx mori, embryonic diapause is induced transgenerationally as a maternal effect. Progeny diapause is determined by the environmental temperature during embryonic development of the mother. Here, we show that the hierarchical pathway consists of a γ-aminobutyric acid (GABA)ergic and corazonin signaling system modulating progeny diapause induction via diapause hormone release, which may be finely tuned by the temperature-dependent expression of plasma membrane GABA transporter. Furthermore, this signaling pathway possesses similar features to the gonadotropin-releasing hormone (GnRH) signaling system for seasonal reproductive plasticity in vertebrates.

To ensure survival under unfavorable environmental conditions and synchronize populations, most insect species enter diapause, which is a seasonal adaptation that evolved as a specific subtype of dormancy (1, 2). Diapause is not a passive response to changing conditions but rather an actively induced state that precedes adverse natural situations. Therefore, this diapause phenotype is accompanied by changes in energy metabolism or storage to improve cold/stress tolerance in later life stages, or progeny via reproductive switch (3). Although it has been generally suggested that brain/neuroendocrine systems are associated with this seasonal reproductive plasticity in both vertebrates and invertebrates (3, 4), the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration into morphological, physiological, behavioral, and reproductive responses, known as the diapause syndrome, remains unclear (3).The silkworm Bombyx mori is a typical insect that arrests normal development during early embryogenesis, which is accompanied by metabolic changes in diapause (5, 6). The development of diapause-destined embryos is arrested during the G2 cell cycle stage immediately after the formation of the cephalic lobe and telson and sequential segmentation of the mesoderm (7). The bivoltine strain of B. mori has two generations per year, and progeny diapause is transgenerationally induced as a maternal effect and is determined by the environmental temperature, photoperiod, and nutrient conditions during embryonic and larval development of the mother (5, 6). The temperature signal during the mother’s embryonic development predominantly affects diapause determination, even if silkworms of the bivoltine Kosetsu strain are exposed to all cases of photoperiods during embryonic and larval development. In the Kosetsu strain, when eggs are incubated at 25 °C under continuous darkness, the resultant female moths (25DD) lay diapause eggs in almost all cases. In contrast, incubation of eggs at 15 °C in dark condition results in moths (15DD) that lay nondiapause eggs in almost all cases (6).Embryonic diapause is induced by the diapause hormone (DH) signaling pathway, which consists of highly sensitive and specific interactions between a neuropeptide, DH, and DH receptor (DHR) (6, 8). DH is exclusively synthesized in seven pairs of neurosecretory cells (DH-PBAN–producing neurosecretory cells [DHPCs]) located within the subesophageal ganglion (SG) in the mother’s generation (6). DH is released into the hemolymph during pupal–adult development and acts on the DHR, which belongs to the G protein-coupled receptors (GPCRs) (9). DH levels in the hemolymph are higher in the 25DD than 15DD pupae in the middle of pupal–adult development when the developing ovaries are sensitive to DH (6). Furthermore, the embryonic Bombyx TRPA1 ortholog (BmTRPA1) acts as a thermosensitive channel that is activated at temperatures above ∼21 °C and affects diapause induction through DH release (10). However, there remain questions about the thermal information that is received by BmTRPA1 and linked to DH signaling to induce diapause.From the 1950s, it has been suggested that the DH release was controlled by signals derived from certain region(s) in the brain based on surgical experiments, such as midsagittal bisection or transection (1113). Especially, the operation in nondiapause producers changed them to diapause producers while transection of the protocerebrum had no effect on the diapause producers. These surgical results suggested the involvement of the protocerebrum in the inhibitory control of DH secretion (12, 14). Furthermore, the accumulation of the ovarian 3-hydroxykynurenine (3-OHK) pigment that accompanies the diapause syndrome was affected by injection with γ-aminobutyric acid (GABA) and the plant alkaloid picrotoxin (PTX), which is a widely used ionotropic GABA and glycine receptor antagonist (15, 16), and the selective ionotropic GABA receptor (GABAR) antagonist bicuculline. This suggests that a GABAergic neurotransmission via ionotropic GABAR is involved in DH secretion, which may be active in nondiapause producers but inactive in diapause producers throughout the pupal–adult development (14, 17). In general, ionotropic GABAR is composed of homo- or hetero-pentameric subunits. All known GABAR subunits display a similar structural scheme, with a large N-terminal extracellular domain involved in the formation of a ligand-binding pocket and a pore domain made of four transmembrane alpha-helices (TM1–TM4) (16, 18). Four homologous sequences of the ionotropic GABAR subunit genes were identified as RDL, LCCH3, GRD, and a GRD-like sequence named 8916 in various insects (19). However, the in vivo physiological roles of both signals derived from the brain and the GABAergic pathway in diapause induction have not been previously investigated.Corazonin (Crz) is an undecapeptide neurohormone sharing a highly conserved amino acid (a.a.) sequence across insect lineages and is involved in different physiological functions, such as heart contraction (20), stress response (21, 22), various metabolic activities (2325), female fecundity (26), melanization of locust cuticles (27), regulation of ecdysis (28, 29), and control of caste identity (30). Moreover, Crz belongs to the gonadotropin-releasing hormone (GnRH) superfamily alongside adipokinetic hormone (AKH) and AKH/Crz-related peptide (ACP). Duplicates of an ancestral GnRH/Crz signaling system occurred in a common ancestor of protostomes and deuterostomes through coevolution of the ligand receptor (31, 32).Herein, we demonstrated that the hierarchical pathway consists of a GABAergic and Crz signaling system modulating progeny diapause induction by acting on DH release. We propose that the PTX-sensitive GABAergic signal may act to chronically suppress Crz release in dorsolateral Crz neurons (under nondiapause conditions) and that diapause conditions (or PTX injection) inhibits GABAergic signaling, resulting in accelerated Crz release, which in turn induces DH release. GABA signaling may be finely tuned by the temperature-dependent expression of the plasma membrane GABA transporter (GAT), which differs between the 25DD and 15DD conditions. Furthermore, this signaling pathway possesses similar features to the GnRH signaling system with respect to seasonal reproductive plasticity in vertebrates.  相似文献   
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桂枝在《伤寒论》中使用广泛,其功效的发挥与剂量、配伍及其比例有着密切关系。桂枝功效的核心是通阳化气,从剂量层次来看,随着桂枝在方剂中剂量的增大,其通阳化气的功效在逐步增强,而在不同剂量层次上分别表现出来不同功效方向,小剂量表现为通阳助气化;中等剂量则表现为解肌疏风、调和营卫,调整阴阳;用至中重剂量,其温通之性更显,主要表现在温通心阳,温补脾阳,通络散寒而除痹症;重剂量使用则温化阴气,而平冲降逆。在看待桂枝在方中的作用时必须同时考虑配伍及比例,配伍可以影响桂枝功效的发挥,而同一配伍的比例调整也体现了中医调整阴阳、辨证论治的核心思想,桂枝功效发挥方向与剂量、配伍及比例关系密切,学习时当综合考虑,着眼于病机、方证、用药,全面把握。  相似文献   
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目的:优选微波技术提取桂枝有效成分的最佳条件。方法:以肉桂酸、桂皮醛的平均提取率为评价指标,采用单因素考察及L9(34)正交表进行试验。结果:微波技术提取桂枝的最佳工艺为:固定90%乙醇为提取溶媒,浸泡时间40min,微波功率4kw,液固比为10,提取时间30min。结论:该优化工艺稳定可行,且提取效率高。  相似文献   
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目的通过网络药理学和分子对接探究钩藤-全蝎药对治疗支气管哮喘的药理作用机制。方法通过TCMSP、TCMIP数据库搜集钩藤、全蝎的活性成分及其作用靶点,并使用Cytoscape软件进行可视化分析成分-靶点网。通过OMIM、GeneCards数据库搜集支气管哮喘的疾病靶点,整合钩藤-全蝎药对与支气管哮喘的共有靶点。利用String平台构建对共有靶点互作PPI网络,并进行GO和KEGG富集分析,通过Cytoscape软件构建成分-靶点-通路网络模型。最后通过Autodock分子对接进行验证。结果经过筛选发现钩藤-全蝎药对37个活性化合物和234个药物靶点,与哮喘6010个靶点取交集得到35个共有靶点。钩藤-全蝎包含槲皮素、山奈酚、育亨宾碱、β-谷甾醇等重要活性成分;根据PPI网络分析,核心网络连接度高的潜在治疗靶点有IL6、CASP3、ECFR、ESR1、MAPK8等;根据KEGG富集分析结果显示,钩藤-全蝎药对主要通过PI3 K-Akt信号通路、TNF信号通路,HIF-1信号通路、M APK信号通路、NF-κB信号通路等来治疗哮喘;钩藤-全蝎药对活性成分与核心靶点的分子对接结果均显示出较好的结合活性。结论钩藤-全蝎药对治疗哮喘呈现出多成分、多靶点、多通路的特点,其核心成分槲皮素、山奈酚、育亨宾碱、β-谷甾醇等可能通过CASP3、MAPK8、ESR1、IL6、ECFR等靶点调节多条通路发挥抗炎、调节免疫、抗氧化应激、改善气道重塑等作用,从而对哮喘达到有效的治疗。  相似文献   
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Body shape is one of the most prominent and basic characteristics of any organism. In insects, abundant variations in body shape can be observed both within and amongst species. However, the molecular mechanism underlying body shape fine‐tuning is very complex and has been largely unknown until now. In the silkworm Bombyx mori, the tubby (tub) mutant has an abnormal short fat body shape and the abdomen of tub larvae expands to form a fusiform body shape. Morphological investigation revealed that the body length was shorter and the body width was wider than that of the Dazao strain. Thus, this mutant is a good model for studying the molecular mechanisms of body shape fine‐tuning. Using positional cloning, we identified a gene encoding the serine protease homologue, B. mori scarface (Bmscarface), which is associated with the tub phenotype. Sequence analysis revealed a specific 312‐bp deletion from an exon of Bmscarface in the tub strain. In addition, recombination was not observed between the tub and Bmscarface loci. Moreover, RNA interference of Bmscarface resulted in the tub‐like phenotype. These results indicate that Bmscarface is responsible for the tub mutant phenotype. This is the first study to report that mutation of a serine protease homologue can induce an abnormal body shape in insects.  相似文献   
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