绿藻硫酸多糖UCS2的结构及抗凝血活性研究

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。     

抗凝血活性海洋硫酸多糖HP1-1的结构研究

目的 对抗凝血活性海洋硫酸多糖HP1-1的结构进行研究。方法 通过高效液相色谱(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)和核磁共振波谱(NMR)方法,对抗凝血活性海洋硫酸多糖HP1-1的结构进行解析。结果 海洋硫酸多糖HP1-1的分子量为297 kDa,总糖和硫酸基含量分别为78.1%和12.3%;HP1-1主要由葡萄糖组成,含有少量半乳糖、阿拉伯糖和甘露糖;HP1-1糖链中含有→4)-Glcp-(1→、→3)-Glcp-(1→、→3,4)-Glcp-(1→、→4)-Arap-(1→、→3,4)-Galp-(1→和→3)-Galp-(1→,硫酸基位于→4)-Glcp-(1→的C-3位和→3)-Galp-(1→的C-4位。 结论 海洋多糖HP1-1是主要由葡萄糖组成的硫酸多糖,含有多种糖基连接方式,为独特结构序列的新颖海洋硫酸甘露阿拉伯半乳葡聚糖。     

海藻多糖UH3的结构特征、抗凝和溶栓活性研究

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。     

1种绿藻硫酸多糖的化学组成及其结构研究

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。     

海洋硫酸多糖PAE的结构和抗病毒活性研究

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。     

沙蚕(Perinereis aibuhitensis)硫酸多糖的结构表征及抗凝血活性研究

目的 对来源于沙蚕（Perinereis aibuhitensis）的硫酸多糖进行结构表征和抗凝血活性研究。方法 采用两步酶解法从沙蚕中提取多糖;利用强阴离子交换色谱和凝胶渗透色谱对粗多糖进行分离纯化;通过离子色谱法、高效液相色谱法（HPLC）、高效凝胶渗透色谱-多角度激光光散射仪（HPGPC-MALLs）联用技术、硫酸软骨素酶ABC酶法分析、核磁共振氢谱（1H-NMR）等方法,研究纯化多糖的化学组成和结构特征;通过测定APTT、PT和TT评价其体外抗凝血活性。结果 从沙蚕中纯化得到了2种硫酸多糖组分PAE1和PAE2,二者的总糖含量、蛋白含量、硫酸根含量及分子量分别为65.21%、14.31%、0.33%、24.49 kDa和53.08%、11.33%、13.46%、57.39 kDa。PAE1主要由Gal（43.58%）、Glc（32.63%）、GalN（8.71%）、GlcA（7.66%）及少量Fuc（2.77%）组成;PAE2主链为硫酸软骨素C（GlcAβ1→3GalNAc6S）,支链主要由Fuc（35.33%）、Gal（20.9%）和Glc（8.98%）构成。PAE1和PAE2均可明显延长APTT和PT。结论 首次从沙蚕中提取、分离得到2种硫酸多糖,其中PAE2是1种含有Fuc、Gal与Glc支链并具有明显的体外抗凝血活性的结构新颖的类硫酸软骨素,该发现为沙蚕硫酸多糖的开发提供了依据。     

海洋真菌Cladosporium Sphaerospermum胞外多糖CS4-1结构特征和抗氧化活性

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。     

绿藻多糖CH1-1的可控降解及其寡糖的制备研究

目的 研究绿藻多糖CH1-1的可控降解及其寡糖的制备。方法 采用不同浓度的三氟乙酸（TFA）或盐酸（HCl）对绿藻多糖CH1-1进行水解,通过薄层色谱和凝胶渗透色谱法研究了水解过程中不同的反应温度和反应时间对多糖降解产物的影响;通过控制酸浓度、反应温度和反应时间,通过Bio-Gel P4凝胶色谱柱分离得到寡糖产物;采用质谱法对得到的寡糖产物进行分析。结果 采用0.1 mol?L-1 和0.05 mol?L-1 TFA或HCl,随着反应温度的升高和反应时间的延长,多糖的分子量降低,其中0.1 mol?L-1 TFA、80 ℃及0.1 mol?L-1 HCl、80 ℃水解条件对多糖的降解作用较好;最终选取0.1 mol?L-1 HCl、80 ℃、3 h的水解条件对多糖进行降解制备寡糖,并采用Bio-Gel P4凝胶色谱柱对寡糖混合物进行分离纯化,电喷雾质谱分析表明,这些寡糖组分为聚合度为1～8的硫酸阿拉伯糖。结论 建立了绿藻多糖CH1-1可控降解方法,制备得到新颖的海洋硫酸寡糖。     

野生与低盐养殖线性硬毛藻(Chaetomorpha linum)多糖的提取分离及其理化性质比较研究△

目的 从野生和低盐养殖线性硬毛藻(Chaetomorpha linum)中提取分离多糖并对其理化性质进行比较分析。方法 以脱脂后的野生和低盐养殖线性硬毛藻为原料,依次经过冷水和热水提取,得到4种粗多糖(WCLC、WCLH、CCLC和CCLH)。运用醋酸纤维素薄膜电泳(CAME)、高效凝胶渗透色谱(HPGPC)、高效液相色谱法(HPLC)、红外光谱法(IR)和核磁共振氢谱(1H-NMR)对其纯度、分子量、单糖组成和结构特征进行分析。结果 粗多糖WCLC、WCLH、CCLC和CCLH得率分别为2.3%,14.3%,3.2%和26.3%;硫酸基含量分别为11.4%,13.0%,9.8%和11.3%;分子量分别为129.5kD,602.3kD,62.85kD和484.2kD。CAME和HPGPC结果显示两种热水提多糖WCLH和CCLH的纯度较高;HPLC分析表明,野生藻和低盐养殖藻多糖中主要含有阿拉伯糖、半乳糖和葡萄糖,但后者中葡萄糖含量较高,WCLC中氨基葡萄糖含量比CCLC的高;1H-NMR分析表明,所有多糖中阿拉伯糖为β-构型,半乳糖为α-构型。结论 野生和低盐养殖线性硬毛藻多糖主要为硫酸阿拉伯半乳聚糖;低盐养殖线性硬毛藻多糖的硫酸基含量低于野生线性硬毛藻,但其葡萄糖含量高于野生线性硬毛藻,表明低盐养殖后,不仅降低其硫酸基含量,而且也会改变多糖中单糖比例。     

不同部位变黑雷松藻（Lessonia nigrescence)多糖的结构及其抗凝活性比较研究

目的 从变黑雷松藻（Lessonia nigrescence）的根部和茎部中分别提取分离得到2种褐藻胶(LNA1, LNA2)与2种褐藻糖胶(LNF1,LNF2),在对其进行理化性质和结构分析基础上,进一步对其抗凝活性进行评价。方法 运用纤维素膜电泳（CME）、高效凝胶渗透色谱（HPGPC）、高效液相色谱（HPLC）对4种多糖进行纯度、分子量和单糖组成分析;采用红外光谱（IR）和核磁共振氢谱（1H-NMR）对4种多糖进行结构分析;通过活化部分凝血活酶时间（APTT）和凝血酶原时间（PT）评价4种多糖抗凝活性。结果 根部褐藻胶中甘露糖醛酸含量（73 %）明显高于颈部（61 %）,LNF1和LNF2均是以岩藻糖、木糖和半乳糖为主的硫酸岩藻聚糖,均能显著延长APTT,但对PT影响较小。结论 变黑雷松藻根部褐藻胶中甘露糖醛酸含量明显高于茎部,褐藻糖胶中的硫酸酯基主要存在于岩藻糖的C4和C2/C3位,且主要通过影响内源凝血途径发挥抗凝作用。     

Affective and Anxiety Disorders and Alcohol and Drug Dependence:

Depression and anxiety frequently coexist in patients with substance use disorders. This clinically-oriented article examiens the relationship between these conditions and emphasizes data showing that substances of abuse can cause signs and symptoms of both depression and anxiety. These substance-related syndromes appear to have a different course and prognosis than uncomplicated, independent anxiety and major depressive disorders, and clinicians should consider the role of alcohol and other drugs in all patients presenting with these complaints. The authors will also outline an approach for diagnosing and managing patients with the combination of a substance use and depressive or anxiety disorder.     

Modelling and simulation of variability and uncertainty in toxicokinetics and pharmacokinetics

Two important methodological issues within the framework of the variability and uncertainty analysis of toxicokinetic and pharmacokinetic systems are discussed: (i) modelling and simulation of the existing physiologic variability in a population; and (ii) modelling and simulation of variability and uncertainty when there is insufficient or not well defined (e.g. small sample, semiquantitative, qualitative and vague) information available. Physiologically based pharmacokinetic models are especially suited for separating and characterising the physiologic variability from the overall variability and uncertainty in the system. Monte Carlo sampling should draw from multivariate distributions, which reflect all levels of existing dependencies in the intact organism. The population characteristics should be taken into account. A fuzzy simulation approach is proposed to model variability and uncertainty when there is semiquantitative, qualitative and vague information about the model parameters and their statistical distributions cannot be defined reliably.     

Synthesis and anti-nociceptive and anti-inflammatory effects of gaultherin and its analogs

The synthesis of gaultherin (1) and its analogs was carried out to provide 11 glycosides under phase-transfer catalytic conditions. The activities of all synthesized compounds were evaluated by nitric oxide production inhibitory assay in vitro. Methyl 2-O-(4-O-β-d-galactopyranosyl)-β-d-glucopyranosylbenzoate (5f) showed significantly anti-nociceptive and anti-inflammatory effects by the evaluation in vivo. Structure–activity relationships within these compounds were discussed.     

Interaction of estrone and estradiol with DNA and protein of liver and kidney in rat and hamster in vivo and in vitro

[6,7-³H] Estrone (E) and [6,7-³H]estradiol-17 (E₂) have been synthesized by reduction of 6-dehydroestrone and 6-dehydroestradiol with tritium gas. Tritiated E and E₂ were administered by oral gavage to female rats and to male and female hamsters on a dose level of about 300 g/kg (54 mCi/kg). After 8 h, the liver was excised from the rats; liver and kidneys were taken from the hamsters. DNA was purified either directly from an organ homogenate or via chromatin. The radioactivity in the DNA was expressed in the units of the Covalent Binding Index, CBI = (mol chemical bound per mol DNA-P)/(mmol chemical administered per kg b.w.). Rat liver DNA isolated via chromatin exhibited the very low values of 0.08 and 0.09 for E and E₂, respectively. The respective figures in hamster liver were 0.08 and 0.11 in females and 0.21 and 0.18 in the males. DNA isolated from the kidney revealed a detectable radioactivity only in the female, with values of 0.03 and 0.05 for E and E₂, respectively. The values for male hamster kidney were < 0.01 for both hormones. The minute radioactivity detectable in the DNA samples does not represent covalent binding to DNA, however, as indicated by two sets of control experiments. (A) Analysis by HPLC of the nucleosides prepared by enzyme digest of liver DNA isolated directly or via chromatin did not reveal any consistent peak which could have been attributed to a nucleoside-steroid adduct. (B) All DNA radioactivity could be due to protein contaminations, because the specific activity of chromatin protein was determined to be more than 3,000 times higher than of DNA. The high affinity of the hormone to protein was also demonstrated by in vitro incubations, where it could be shown that the specific activity of DNA and protein was essentially proportional to the concentration of radiolabelled hormone in the organ homogenate, regardless of whether the animal was treated or whether the hormone was added in vitro to the homogenate.Carcinogens acting by covalent DNA binding can be classified according to potency on the basis of the Covalent Binding Index. Values of 10³–10⁴ have been found for potent, 10² for moderate, and 1–10 for weak carcinogens. Since estrone is moderately carcinogenic for the kidney of the male hamster, a CBI of about 100 would be expected. The actually measured limit of detection of 0.01 places covalent DNA binding among the highly unlikely mechanisms of action. Similar considerations can be made for the liver where any true covalent DNA binding must be below a level of 0.01. It is concluded that an observable tumor induction by estrone or estradiol is unlikely to be due to DNA binding.Paper presented at the Satellite Symposium of the European Society of Toxicology, Rome, March 29, 1983     

Antiinfective and encrustation-inhibiting materials--myth and facts

Catheters, urethral and ureteral stents and other urological implants are frequently affected by encrustration and infection due to their permanent contact with urine. Indwelling urinary catheters provide a haven for microorganisms and thus require extensive monitoring. Several surface modification techniques have been proposed to improve the performance of devices including the immobilization of biomolecules, the incorporation of hydrophilic grafts to reduce protein adsorption, the creation of hydrophobic surfaces, the creation of microdomains to regulate cellular and protein adhesion, new polymers and antimicrobial coatings. Physico-chemical explanation to elucidate the mechanism of such encrustation or infection inhibiting materials is still not available. Our series of experiments showed a marked decrease of silver-activity in biological fluids which corresponds with the controversial clinical results obtained with silver coated urinary catheters. Rifampicin/minocycline coated catheters had very low activity against Gram-negative rods, enterococci and Candida spp., the main causing organisms of urinary catheter infection. Surface engineered materials and antimicrobial drug delivery systems will be the next generation of sophisticated urinary catheters and stents, if both efficacy as well as efficiency has been proved clinically.     

成骨细胞的功能与损伤和骨质疏松的防治

骨质疏松是一种全身性骨骼疾病,导致骨折风险增加。成人的骨量通过破骨细胞的骨吸收和成骨细胞的骨形成作用来维持动态平衡,治疗骨质疏松症的理想策略是抑制破骨细胞的骨吸收和/或增强成骨细胞的骨形成功能。目前针对保护成骨细胞及增强其功能的骨质疏松疗法相对较少。因此,本文针对成骨细胞相关功能蛋白、各种细胞损伤机制（内质网应激、氧化应激、机械过载、微小RNA和长链非编码RNA的影响等）及骨质疏松的治疗与预防作一综述,以期为针对增强成骨细胞功能的骨质疏松治疗策略提供新思路。     

益生菌与肿瘤防治

益生菌广泛存在于自然界中,通过维持宿主体内菌群平衡、影响肠屏障功能和调节免疫应答等作用,提高宿主健康水平,被公认为"肠道健康卫士".一些益生菌可以增强机体的免疫功能,抑制致癌物质,影响肿瘤细胞的基因表达,对肿瘤具有拮抗作用.大量研究表明,益生菌在未来的肿瘤防治中有很好的应用和发展前景.     

Self-stimulation and amphetamine: Tolerance to d and l isomers and cross tolerance to cocaine and methylphenidate

The effects of the d and l isomers of amphetamine on self-stimulation responding were tested following acute and chronic administration. Tolerance and post-drug depression of responding occurred in tests with both isomers, indicating no role for p-hydroxynorephedrine (PHN) which is one of the metabolites of d-amphetamine. In the second experiment, d-amphetamine, methylphenidate and cocaine all produced quantitatively and qualitatively similar effects on self-stimulation responding following acute administration. Following chronic administration of d-amphetamine, animals showed tolerance to all three drugs, indicating cross-tolerance among them. These data are consistent with an hypothesis that tolerance and post-drug depression following chronic amphetamine treatment are the result of decreases in postsynaptic receptor sensitivity, which would lead to a decreased effectiveness of all three drugs, regardless of their pre-synaptic mechanisms.     

Isolation and characterization of glycosylated and non-glycosylated prolactins from alligator and crocodile

Two molecular forms of prolactin (PRL). glycosylated and non-glycosylated, were isolated from pituitary glands of two reptiles, alligator and crocodile. The reptilian PRLs were extracted under alkaline conditions from the precipitate obtained after pituitaries were first extracted with 0.25 m sucrose, 1 mM NH₄HCO₃, pH 6.3. Purification was performed by ion exchange chromatography on DE-52, gel filtration on Sephadex G-75 superfine, and reversed phase high performance liquid chromatography. Two forms of both alligator and crocodile PRL, designated PRLI and PRLII, with molecular weights of 26000 and 24000 were isolated. Alligator and crocodile PRLI and PRLII were stained specifically in immunoblots with anti-sea turtle PRL and anti-ostrich PRL. Sequence analysis revealed that both forms of alligator and crocodile PRLs consisted of 199 amino acid residues with a glycosylation consensus sequence (Asn-Ala-Ser) at position 60 in alligator and crocodile PRLs with a molecular weight of 26000 (PRLI). In contrast, Thr was substituted for Asn at position 60 in the PRLs with a molecular weight of 24000 (PRLII). The sequences of alligator PRLs differed from crocodile PRLs only in position 134: Val for alligator PRLs and He for crocodile PRLs. There is a high degree of structural conservation between the reptilian PRLs isolated in this study and avian PRL; each showed 92% sequence identity with chicken PRL and 89% with turkey PRL.