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1.
目的 对绿藻多糖UCS2的结构特征和抗凝血活性进行研究。方法 通过冷水提取、强阴离子交换色谱和凝胶渗透色谱,从绿藻花石莼中提取分离得到硫酸多糖UCS2;采用高效凝胶渗透色谱(HPGPC)、高效液相色谱、红外光谱和气质联用色谱对多糖UCS2的结构进行表征;通过活化部分凝血活酶时间(APTT)、凝血酶时间、凝血酶原时间对多糖UCS2体外抗凝血活性进行研究。结果 绿藻多糖UCS2分子量为39.55kDa,硫酸根和糖醛酸含量分别为19.74%和18.66%;UCS2主要由鼠李糖组成,含有少量葡糖醛酸和木糖。糖链中含有→3,4)-α-L-Rhap-(1→, →4)-α-L-Rhap-(1→, →4)-β-D-Xylp-(1→和→4)-β-D-GlcAp-(1→,硫酸基位于→4)-α-L-Rhap-(1→的C-3位。多糖UCS2对APTT有显著延长作用,具有较高的抗凝活性。结论 绿藻多糖UCS2是1种抗凝活性的葡萄糖醛酸-木糖-鼠李糖型硫酸多糖。  相似文献   

2.
目的 对绿藻多糖SHW及其低分子量片段的结构及抗凝活性进行研究。方法 通过热水提取、强阴离子交换色谱和凝胶渗透色谱,从绿藻硬毛藻中提取分离得到硫酸多糖SHW;通过可控酸解方法制备SHW低分子量片段;采用高效凝胶渗透色谱、高效液相色谱、红外光谱及甲基化方法对多糖结构进行表征;通过活化部分凝血活酶时间、凝血酶时间、凝血酶原时间研究多糖SHW及其低分子量片段体外抗凝血活性。结果 多糖SHW及其低分子量片段主要由阿拉伯糖组成,含有少量半乳糖和氨基葡萄糖;糖链中阿拉伯糖主要以→4)-Arap-(1→和→3,4)Arap-(1→的形式存在,半乳糖以→4)-Galp-(1→存在形式,硫酸根主要位于→4)-Arap-(1→的C-3位。SHW及其低分子量片段A1~A6的分子量分别为492 kDa、200 kDa、170kDa、100kDa、26kDa、14kDa 和10 kDa。SHW 具有较高的抗凝血活性,且其抗凝活性随着其分子量的减少而降低。结论 海藻多糖SHW是一种具有抗凝活性的新颖硫酸多糖,其抗凝活性与分子量密切相关。  相似文献   

3.
目的 对海藻多糖UH3的结构特征、抗凝血和溶栓活性进行研究。方法 通过热水提取法,从海藻中提取硫酸多糖,采用强阴离子交换色谱和凝胶渗透色谱对多糖进行分离纯化;采用高效液相色谱、高效凝胶渗透色谱(HPGPC)、红外光谱及甲基化方法对多糖的结构进行表征;通过活化部分凝血活酶时间(APTT)、凝血酶时间(TT)、凝血酶原时间(PT)及血凝块溶解法研究多糖体外抗凝血和溶栓活性。结果 多糖UH3在HPGPC色谱图上呈单一对称峰,分子量为50.3 kDa,硫酸根和糖醛酸含量分别为12.27和12.85%;UH3主要由鼠李糖组成,含有少量葡萄糖醛酸和木糖;UH3糖链中鼠李糖主要以→4)-Rhap-(1→、 →3,4)-Rhap-(1→及少量的T-Rhap形式存在,木糖以→4)-Xylp-(1→和T-Xylp存在形式,糖醛酸以→4)-GlcAp-(1→和T-GlcAp形式存在;硫酸根主要位于→4)-Rhap-(1→的C-3位。多糖UH3对APTT和TT有显著延长作用,并能明显提高溶栓率。结论 海藻多糖UH3是一种结构新颖的具有抗凝和溶栓活性的硫酸多糖。  相似文献   

4.
目的 对肠浒苔来源的硫酸多糖的结构和抗病毒活性进行研究。 方法 通过稀碱提取法,从肠浒苔中提取硫酸多糖,采用强阴离子交换色谱和凝胶渗透色谱对多糖进行分离纯化;采用高效液相色谱(HPLC)、高效凝胶渗透色谱(HPGPC)、傅里叶变换红外光谱(IR)以及气质联用色谱(GC-MS)方法对多糖的结构进行表征;采用细胞病变效应测定PAE对不同病毒的抑制率。 结果 从肠浒苔中分离得到多糖PAE,其分子量为13.98 kDa,主要由鼠李糖、葡萄糖醛酸和木糖构成,糖链主要由(1→4)-Rhap,(1→3,4)-Rhap,(1→2,4)-Rhap,Xylp(1→和(1→4)-Glcp组成,硫酸根主要位于(1→4)-Rhap 的C-2或C-3位以及Xylp(1→的C-4位上,PAE具有良好的抗病毒活性,特别是对呼吸道合胞体病毒的抑制率较高。 结论 海洋多糖PAE是一种结构新颖的由鼠李糖、葡萄糖醛酸和木糖组成的硫酸多糖,具有良好的抗病毒活性。  相似文献   

5.
目的 对1种绿藻硫酸多糖的化学组成及其结构特征进行研究。方法 通过热水提取法,从1种石莼属海藻中提取硫酸多糖,采用强阴离子交换色谱和凝胶渗透色谱对多糖进行分离纯化;采用高效凝胶渗透色谱(HPGPC)、高效液相色谱以及化学方法对多糖的纯度、分子量、单糖组成和化学成分进行分析测定;通过红外光谱和气质联用方法对多糖的结构进行表征。结果 多糖HP2S在HPGPC色谱图上呈单一对称峰,分子量为90.5 kDa,硫酸根和糖醛酸含量分别为32.1%和7.4%,HP2S主要由鼠李糖组成,含有少量葡萄糖、葡萄糖醛酸、半乳糖和木糖,HP2S糖链中鼠李糖主要存在形式为(1→2)-Rhap 、(1→3)-Rhap 和(1→2, 3)-Rhap,硫酸根位于(1→3)-Rhap 的C-2位或(1→2)-Rhap 的C-3位上。结论 水溶性多糖HP2S是1种结构新颖的主要由鼠李糖组成的硫酸化多糖。  相似文献   

6.
目的 对海洋真菌Cladosporium Sphaerospermum产生的胞外多糖CS4-1结构特征和抗氧化活性进行研究。方法 利用乙醇沉淀法、强阴离子交换色谱和凝胶渗透色谱对菌株所产胞外多糖进行分离纯化,运用PMP柱前衍生高效液相色谱法、高效凝胶渗透色谱法、气质联用色谱和化学方法分析多糖的结构特征,通过测定DPPH自由基、羟基自由基、ABTS自由基和超氧阴离子自由基清除活性以及还原能力评价多糖的抗氧化活性。结果 从海洋真菌Cladosporium Sphaerospermum发酵液中分离纯化得到胞外多糖CS4-1,其分子量为21.49 kDa;CS4-1含有甘露糖和半乳糖;糖链主要由Manp-(1→、→2)-Galp-(1→和→6)-Manp-(1→构成;CS4-1具有较好的抗氧化活性,在测定的5种活性指标中,清除超氧阴离子自由基的能力最强。结论 首次从海洋真菌Cladosporium Sphaerospermum分离得到抗氧化活性较好的多糖CS4-1,它是结构新颖的胞外多糖。  相似文献   

7.
褐藻硫酸岩藻聚糖是来源于褐藻的结构复杂的一类海洋硫酸多糖,主要由岩藻糖、半乳糖、甘露糖和葡萄糖醛酸组成,并含有少量的木糖、葡萄糖、鼠李糖、阿拉伯糖和氨基葡萄糖。研究表明,褐藻硫酸岩藻聚糖的主链是由 α (1→3) 或 α (1→3)、α (1→4) 交替连接的硫酸化L-岩藻糖构成,还嵌有半乳糖、葡萄糖醛酸等,而厚叶解曼藻和羊栖菜等褐藻硫酸岩藻聚糖的主链是由1→2甘露糖和1→4葡萄糖醛酸构成二糖重复单元。褐藻硫酸岩藻聚糖的主链上普遍存在岩藻糖、半乳糖、甘露糖或葡萄糖醛酸等寡糖的支链,因此糖链结构复杂。硫酸岩藻聚糖的硫酸根位于L-岩藻糖的C-2、C-3或C-4位,也存在C-2,4双硫取代。目前,褐藻硫酸岩藻聚糖结构的分析技术主要为甲基化法分析、核磁共振、二维核磁共振技术和串联质谱分析技术等。本文对褐藻来源硫酸岩藻聚糖的化学组成和结构以及常用分析技术进行了总结,为褐藻硫酸岩藻聚糖的结构分析以及构效关系研究提供依据。  相似文献   

8.
目的 对北极海洋真菌Aspergillus jensenii胞外多糖的结构及抗氧化活性进行研究。方法 采用醇沉法提取、强阴离子交换色谱和凝胶渗透色谱对胞外多糖进行分离纯化;运用PMP柱前衍生高效液相色谱、高效凝胶渗透色谱、气相色谱-质谱和核磁共振波谱对多糖结构进行分析;通过测定ABTS自由基、DPPH自由基、羟基自由基和超氧阴离子自由基的清除能力评价多糖抗氧化活性。结果 分离得到1种多糖AJ1-1,其主要由甘露糖和少量半乳糖组成,糖链是以→2)-α-D-Manp-(1→和→6)-α-D-Manp-(1→为主,分支位于→2)-α-D-Manp-(1→的C-6位和→6)-α-D-Manp-(1→的C-2位,支链由Galf和Manp组成;AJ1-1具有较强的清除自由基能力(特别是对ABTS自由基、DPPH自由基和羟基自由基)。结论 首次从北极海洋真菌Aspergillus jensenii发酵液中分离得到含有呋喃型半乳糖分支的新颖半乳甘露聚糖,其是1种潜在的抗氧化多糖。  相似文献   

9.
麦冬多糖Md-1、Md-2化学结构的研究   总被引:4,自引:0,他引:4  
目的 研究中药麦冬中的多糖化学结构。方法 采用柱层析法进行纯化 ,并用红外光谱和核磁等方法阐明 Md- 1、Md- 2的化学结构。结果  Md- 1、Md- 2的相对分子质量分别为 2 70 6 4和 4 86 5 1。Md- 1、Md- 2多糖的糖单元基本组成是葡萄糖。其中 Md- 1多糖中平均每 8个葡萄糖单元中连有 1个硫酸基 ,Md- 2多糖中平均每 6个葡萄糖单元中连有 1个硫酸基。构型均为α型 ,单糖的连接方式为 1→ 4连接。结论  Md- 1、Md- 2多糖的化学结构均为有一甲醚基取代的 α- D- (1→ 4 )的葡聚糖 ,两种多糖的相对分子质量和硫酸基的含量不同  相似文献   

10.
一种紫贻贝水提多糖的理化性质和结构分析   总被引:1,自引:0,他引:1  
目的从紫贻贝中提取和分离纯化多糖,并对其基本理化性质和结构进行分析,为紫贻贝多糖活性研究提供基础。方法将紫贻贝鲜肉制成丙酮粉后,经60℃热水提取,去核酸和采用Sepharcryl S-300凝胶层析分离得到了一种水溶性多糖组分(HWS)。采用硫酸-苯酚法、Folin-酚法、柱前衍生高效液相色谱法和高效凝胶渗透色谱法分别对HWS的总糖含量、蛋白含量、单糖组成、相对分子质量进行了测定,并通过甲基化和气质联用(GC/MS)分析、红外光谱(FT-IR)、核磁共振(NMR)技术对HWS的结构进行了分析。结果 HWS是以(1→4)-α-D-Glcp为主链,含有少量的→2,4)-Glcp-(1→和→6)-β-Glc-(1→分支的葡聚糖,平均每6个主链糖残基含有1个分支。结论采用60℃热水提取和凝胶柱层析分离得到紫贻贝多糖,通过多种化学分析及现代仪器分析技术确定了HWS的结构,为紫贻贝多糖活性的深入研究提供了参考和借鉴。  相似文献   

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The sphingolipid sphingosine-1-phosphate (S1P) acts on five subtypes of G-protein- coupled receptors, termed S1P(1) (formerly endothelial differentiation gene-1 [Edg-1]), S1P(2) (Edg-5), S1P(3) (Edg-3), S1P(4) (Edg-6) and S1P(5) (Edg-8), and possibly several other "orphan" receptors, such as GPR3, GPR6 and GPR12. These receptors are coupled to different intracellular second messenger systems, including adenylate cyclase, phospholipase C, phosphatidylinositol 3-kinase/protein kinase Akt, mitogen-activated protein kinases, as well as Rho- and Ras-dependent pathways. Consistently with this receptor multiplicity and pleiotropic signaling mechanisms, S1P influences numerous cell functions. S1P(1)1, S1P(2) and S1P(3) receptors are the major S1P receptor subtypes in the cardiovascular system, where they mediate the effects of S1P released from platelets, and possibly other tissues (such as brain). Thus S1P(1) and S1P(3) receptors enhance endothelial and vascular smooth muscle cell proliferation and migration, playing a key role in developmental and pathological angiogenesis. In contrast, S1P(2) receptors inhibit migration of these cell types, probably because of their unique stimulatory effect on a GTPase-activating protein inhibiting the activity of Rac. S1P receptors can also cause relaxation and constriction of blood vessels. The former effect is mediated by pertussis toxin-sensitive receptors (possibly S1P(1)) located on the endothelium and stimulating phosphatidylinositol 3-kinase/Akt/endothelial nitric oxide synthase (eNOS). The vasoconstricting effect of S1P is likely to be mediated by S1P(2) and/or S1P(3) receptors, via Rho-Rho-kinase, and is more potent in coronary and cerebral blood vessels. Finally, S1P also protects endothelial cells from apoptosis through activation of phosphatidylinositol 3-kinase/Akt/eNOS via S1P(1) and S1P(3) receptors. The variety of these effects, taken together with the existence of multiple receptor subtypes, provides an abundance of therapeutic targets that currently still await the development of selective agents.  相似文献   

14.
Sulfation is an important component of human thyroid hormone metabolism. The role of the human sulfotransferase 1C1 (SULT1C1) is not known. Because SULT1C1 is present in the adult thyroid, intra-thyroidal sulfation of thyroid hormones and their metabolites might occur. We tested this hypothesis by determining the ability of recombinant human SULT1C1 to catalyze iodothyronine sulfation. Apparent K(m) values for 3,3',5-triiodothyronine (T(3)), 3, 3'-diiodothyronine (3,3'-T(2)), 3',5',3-triiodothyronine (rT(3)), and 3,3',5,5'-tetraiodothyronine (T(4)) with SULT1C1 were 28.7, 10.3, 10.2, and 59.3 microM, respectively. Thermal stability and responses to inhibitors also were tested with T(3) as the substrate. Enzyme aliquots were measured simultaneously to determine SULT1C1 substrate preferences at optimal iodothyronine concentrations. SULT1C1 activity obtained with T(3) was used as 100%, and the activities with 3,3'-T(2), rT(3), T(4), and 3,5-diiodothyronine (3, 5-T(2)) were 614, 314, 25, and 4%, respectively. We report for the first time the characterization of human SULT1C1 with T(3) and the preferences of the enzyme for various iodothyronines. The presence of SULT1C1 in the adult thyroid gland raises the possibilities that the enzyme can contribute to intraglandular thyroid hormone processing and iodide reutilization.  相似文献   

15.
目的证明间质作用因子(stromal interaction molecule1,Stim1)在FBJ诱导的小鼠骨肉瘤细胞中的抑癌作用。方法在Stim1高表达的FBJ-S1-H细胞采用Stim1以siRNA干扰技术得到Stim1沉默的几株S1-H单克隆细胞株,通过细胞行为学方法和RT-PCR技术对其mRNA进行研究,通过明胶酶谱法对细胞基质金属酶活性进行研究。结果通过细胞行为学方法证明,Stim1的沉默提高了细胞的迁移性,通过对mRNA表达的研究发现,Stim1沉默引起了多种基因表达的变化,其中包括基质金属酶9(matrix mexalloprotelnase 9,MMP-9)的升高,窖蛋白(caveolinl,Cav1),甾醇调控因子Srebf1的降低等,提高单克隆细胞中的Cav1含量可以使细胞迁移性降低。结论实验结果证明在FBJ-S1-H细胞中,Stim1能够抑制细胞的移动性,沉默Stim1的表达能够提高细胞的迁移性。  相似文献   

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Antimycobacterial 1-Phenyl-1-alkylaminoalkanes Synthesis and testing for antimycobacterial properties (M. tuberculosis H 37 Ra, Middlebrook-7H9-broth) of 1-phenyl-1-alkylaminoalkanes, which differ from antimycobacterial N-alkylbenzylamines by an additional alkyl chain in α-position, is described. By variation of both alkyl chains and introduction of one or two Cl-substituents in the aromatic ring the activity increases up to an optimum within the homologous series. Overstepping optimal lipophilicity or ramification of the alkyl chains decrease activity. Compounds 19, 20, 33-35, 51-53, 61-63, 65-67, 70-73, 96 and 102 - 104 inhibit the growth of M. tuberculosis in concentrations of 2 to 4 μg/ml.  相似文献   

18.
Both benzo[a]pyrene (BaP) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are potent ligands of aryl hydrocarbon receptors (AhR). Although animal studies indicate that both compounds induce pathological changes in the peripheral lung, the specific cell type involved remains unclear. Clara cells, expressing Clara cell specific protein (CCSP) and abundant in cytochrome P450, are nonciliated bronchiolar epithelial cells in the peripheral lung. Here we explore the hypothesis that CCSP-positive Clara cells are highly responsive to AhR ligands and are the primary cell type involved in BaP- and TCDD-induced toxicities. The responsiveness to AhR ligands was evaluated by measuring the respective mRNA and protein levels of cytochrome P450 1A1 (CYP1A1) and 1B1 (CYP1B1) using real-time RT-PCR and immunocytochemistry assays. Two in vitro models were used: primary cultures of human small airway epithelial (SAE) cells and rat lung slice cultures. In the presence of calcium, human SAE cells differentiated into CCSP-positive cells. BaP- and TCDD-induced mRNA and protein levels of CYP1A1 and CYP1B1 levels were significantly elevated in CCSP-positive cell cultures. Similarly, AhR mRNA and protein levels were increased in CCSP-positive cell cultures, as determined by real-time RT-PCR and Western blot analysis. When rat lung slice cultures were treated with BaP or TCDD for 24 h, CYP1A1 and CYP1B1 proteins were strongly induced in Clara cells. These results indicate that, in the peripheral lung of both rats and humans, CCSP-positive cells (Clara cells) may be more sensitive to AhR ligands than other cell types.  相似文献   

19.
Crossing the Cyp1a1/1a2(-/-) double-knockout mouse with the Cyp1b1(-/-) single-knockout mouse, we generated the Cyp1a1/1a2/1b1(-/-) triple-knockout mouse. In this triple-knockout mouse, statistically significant phenotypes (with incomplete penetrance) included slower weight gain and greater risk of embryolethality before gestational day 11, hydrocephalus, hermaphroditism, and cystic ovaries. Oral benzo[a]pyrene (BaP) daily for 18 days in the Cyp1a1/1a2(-/-) produced the same degree of marked immunosuppression as seen in the Cyp1a1(-/-) mouse; we believe this reflects the absence of intestinal CYP1A1. Oral BaP-treated Cyp1a1/1a2/1b1(-/-) mice showed the same "rescued" response as that seen in the Cyp1a1/1b1(-/-) mouse; we believe this reflects the absence of CYP1B1 in immune tissues. Urinary metabolite profiles were dramatically different between untreated triple-knockout and wild-type; principal components analysis showed that the shifts in urinary metabolite patterns in oral BaP-treated triple-knockout and wild-type mice were also strikingly different. Liver microarray cDNA differential expression (comparing triple-knockout with wild-type) revealed at least 89 genes up- and 62 genes down-regulated (P-value < or = 0.00086). Gene Ontology "classes of genes" most perturbed in the untreated triple-knockout (compared with wild-type) include lipid, steroid, and cholesterol biosynthesis and metabolism; nucleosome and chromatin assembly; carboxylic and organic acid metabolism; metal-ion binding; and ion homeostasis. In the triple-knockout compared with the wild-type mice, response to zymosan-induced peritonitis was strikingly exaggerated, which may well reflect down-regulation of Socs2 expression. If a single common molecular pathway is responsible for all of these phenotypes, we suggest that functional effects of the loss of all three Cyp1 genes could be explained by perturbations in CYP1-mediated eicosanoid production, catabolism and activities.  相似文献   

20.
《Drugs in R&D》2002,3(1):50-51
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