• 【氟化分子在中枢神经系统中作为药物和显像剂。】 复制标题 收藏 收藏
    DOI:10.2174/156802606777951046 复制DOI
    作者列表:Sun S,Adejare A
    BACKGROUND & AIMS: :The strategic use of fluorine substitution in drug discovery and drug development is well documented. The small size and high electronegativity of fluorine are among properties of this element that lend special advantages. Applications in drugs targeted to the central nervous system (CNS) have been particularly fruitful in addition to favorable properties seen in many peripherally acting drugs. Fluorine substitution can be used to solve problems unique to the CNS, such as blood brain barrier (BBB) penetration. Likewise, use of the positron emitting isotope, (18)F, provides a unique tool for non-invasive imaging and diagnoses in the CNS. In this review, fluorine in CNS drugs and drug discovery are discussed.
    背景与目标: :氟取代在药物发现和药物开发中的战略用途已得到充分证明。氟的小尺寸和高电负性是该元素的特性之一,具有特殊的优势。除了在许多外围作用药物中看到的有利特性外,在针对中枢神经系统(CNS)的药物中的应用也特别富有成果。氟取代可用于解决CNS独有的问题,例如血脑屏障(BBB)渗透。同样,正电子发射同位素(18)F的使用为CNS中的非侵入性成像和诊断提供了独特的工具。在这篇综述中,讨论了中枢神经系统药物中的氟和药物发现。
  • 【膜联蛋白V磁激活细胞分选分离后精子恢复的评估。】 复制标题 收藏 收藏
    DOI:10.1016/s1472-6483(10)61437-x 复制DOI
    作者列表:Said TM,Agarwal A,Grunewald S,Rasch M,Glander HJ,Paasch U
    BACKGROUND & AIMS: :Magnetic-activated cell sorting (MACS) using paramagnetic annexin V-conjugated microbeads eliminates spermatozoa with externalized phosphatidylserine, which is considered one of the features of apoptosis. The objective of this study was to evaluate sperm recovery following the use of MACS as a sperm preparation technique. Mature spermatozoa were separated and divided into two fractions: the first was prepared by density gradient centrifugation (DGC) and MACS, while the second was prepared by DGC only. Following MACS, the percentage of cells collected in the annexin-negative fraction was significantly higher than the annexin-positive fraction and the sperm recovery rate was 73.8 +/- 12.1%. In conclusion, the integration of MACS with DGC can be considered as an effective sperm preparation technique that does not lead to significant cell loss. Separating a distinctive population of non-apoptotic spermatozoa with intact membranes may optimize the outcome of assisted reproduction.
    背景与目标: :使用顺磁性膜联蛋白V偶联的微珠进行磁激活细胞分选(MACS),消除了带有外部磷脂酰丝氨酸的精子,这被认为是细胞凋亡的特征之一。这项研究的目的是评估使用MACS作为精子制备技术后的精子回收率。将成熟的精子分离并分为两部分:第一部分通过密度梯度离心(DGC)和MACS制备,而第二部分仅通过DGC制备。进行MACS后,在膜联蛋白阴性组分中收集的细胞百分比显着高于膜联蛋白阳性组分,精子回收率为73.8 / 12.1%。总之,MACS与DGC的整合可以被认为是一种有效的精子制备技术,不会导致明显的细胞损失。用完整的膜分离非凋亡性精子的独特群体可以优化辅助生殖的结果。
  • 【前沿:鼻咽相关淋巴组织器官发生的起始和成熟所需淋巴趋化因子的独特性。】 复制标题 收藏 收藏
    DOI:10.4049/jimmunol.177.7.4276 复制DOI
    作者列表:Fukuyama S,Nagatake T,Kim DY,Takamura K,Park EJ,Kaisho T,Tanaka N,Kurono Y,Kiyono H
    BACKGROUND & AIMS: :CD3(-)CD4(+)CD45(+) inducer cells are required for the initiation of mucosa-associated organogenesis of both nasopharynx-associated lymphoid tissues (NALT) and Peyer's patches (PP) in the aerodigestive tract. CXCL13(-/-) mice and mice carrying the paucity of lymph node T cell (plt) mutation and lacking expression of CCL19 and CCL21 accumulate CD3(-)CD4(+)CD45(+) cells at the site of NALT but not of PP genesis. Although NALT was observed to develop in adult CXCL13(-/-) and plt/plt mice, the formation of germinal centers in CXCL13(-/-) mice was affected, and their population of B cells was much lower than in the NALT of CXCL13(+/-) mice. Similarly, fewer T cells were observed in the NALT of plt/plt mice than in control mice. These findings indicate that the initiation of NALT organogenesis is independent of CXCL13, CCL19, and CCL21. However, the expression of these lymphoid chemokines is essential for the maturation of NALT microarchitecture.
    背景与目标: :CD3(-)CD4()CD45()诱导细胞是启动鼻咽相关淋巴样组织(NALT)和淋巴集结(PP)在消化道中黏膜相关器官发生的开始所必需的。 CXCL13(-/-)小鼠和携带淋巴结T细胞(plt)突变且缺乏CCL19和CCL21表达的小鼠在NALT部位积累了CD3(-)CD4()CD45()细胞,但没有PP发生。尽管观察到NALT在成年CXCL13(-/-)和plt / plt小鼠中发育,但是CXCL13(-/-)小鼠生发中心的形成受到影响,其B细胞数量远低于NALT的NALT。 CXCL13(/-)小鼠。同样,在plt / plt小鼠的NALT中观察到的T细胞少于对照小鼠。这些发现表明NALT器官发生的启动独立于CXCL13,CCL19和CCL21。但是,这些淋巴趋化因子的表达对于NALT微结构的成熟至关重要。
  • 【变形链球菌的atlA操纵子:在自溶素成熟和细胞表面生物发生中的作用。】 复制标题 收藏 收藏
    DOI:10.1128/JB.00536-06 复制DOI
    作者列表:Ahn SJ,Burne RA
    BACKGROUND & AIMS: :The Smu0630 protein (AtlA) was recently shown to be involved in cell separation, biofilm formation, and autolysis. Here, transcriptional studies revealed that atlA is part of a multigene operon under the control of at least three promoters. The morphology and biofilm-forming capacity of a nonpolar altA mutant could be restored to that of the wild-type strain by adding purified AtlA protein to the medium. A series of truncated derivatives of AtlA revealed that full activity required the C terminus and repeat regions. AtlA was cell associated and readily extractable from with sodium dodecyl sulfate. Of particular interest, the surface protein profile of AtlA-deficient strains was dramatically altered compared to the wild-type strain, as was the nature of the association of the multifunctional adhesin P1 with the cell wall. In addition, AtlA-deficient strains failed to develop competence as effectively as the parental strain. Mutation of thmA, which can be cotranscribed with atlA and encodes a putative pore-forming protein, resulted in a phenotype very similar to that of the AtlA-deficient strain. ThmA was also shown to be required for efficient processing of AtlA to its mature form, and treatment of the thmA mutant strain with full-length AtlA protein did not restore normal cell separation and biofilm formation. The effects of mutating other genes in the operon on cell division, biofilm formation, or AtlA biogenesis were not as profound. This study reveals that AtlA is a surface-associated protein that plays a critical role in the network connecting cell surface biogenesis, biofilm formation, genetic competence, and autolysis.
    背景与目标: :最近发现,Smu0630蛋白(AtlA)与细胞分离,生物膜形成和自溶有关。在这里,转录研究表明atlA是多基因操纵子的一部分,在至少三个启动子的控制下。通过向培养基中添加纯化的AtlA蛋白,可以将非极性altA突变体的形态和生物膜形成能力恢复为野生型菌株。 AtlA的一系列截短的衍生物表明,完整的活性需要C末端和重复区域。 AtlA与细胞相关,可以很容易地用十二烷基硫酸钠提取。特别令人感兴趣的是,与野生型菌株相比,AtlA缺陷型菌株的表面蛋白质谱发生了巨大变化,多功能黏附素P1与细胞壁的缔合性质也是如此。另外,缺乏AtlA的菌株不能像亲本菌株一样有效地发展能力。可以与atlA共转录并编码推定的成孔蛋白的thmA突变产生的表型与缺乏AtlA的菌株非常相似。还显示ThmA是有效将AtlA加工成其成熟形式所必需的,并且用全长AtlA蛋白处理thmA突变株不能恢复正常的细胞分离和生物膜形成。操纵子中其他基因突变对细胞分裂,生物膜形成或AtlA生物发生的影响并不那么深远。这项研究表明,AtlA是一种表面相关蛋白,在连接细胞表面生物发生,生物膜形成,遗传能力和自溶作用的网络中起关键作用。
  • 【某些derivatives衍生物作为新的抗癌和抗癌剂的合成和生物学评价。】 复制标题 收藏 收藏
    DOI:10.1016/j.ejmech.2012.10.011 复制DOI
    作者列表:Altıntop MD,Özdemir A,Turan-Zitouni G,Ilgın S,Atlı Ö,İşcan G,Kaplancıklı ZA
    BACKGROUND & AIMS: :New hydrazone derivatives were synthesized via the nucleophilic addition-elimination reaction of 2-[(1-methyl-1H-tetrazol-5-yl)thio)]acetohydrazide with aromatic aldehydes/ketones. The compounds were tested in vitro against various Candida species and compared with ketoconazole. Genotoxicity of the most effective anticandidal compounds was evaluated by umuC and Ames assays. All compounds were also investigated for their cytotoxic effects on NIH3T3 and A549 cell lines. Compound 8 was the most effective antifungal derivative against C. albicans (ATCC-90028) with a MIC value of 0.05 mg/mL. Compound 5 can be identified as the most promising anticancer agent against A549 cancer cell lines due to its inhibitory effect on A549 cell lines and low toxicity to NIH3T3 cells.
    背景与目标: :通过2-[((1-甲基-1H-四唑-5-基)硫基)]乙酰肼与芳香族醛/酮的亲核加成消除反应合成了新的衍生物。该化合物在体外针对各种念珠菌进行了测试,并与酮康唑进行了比较。通过umuC和Ames分析评估了最有效的抗候选化合物的基因毒性。还研究了所有化合物对NIH3T3和A549细胞系的细胞毒性作用。化合物8是针对白色念珠菌的最有效的抗真菌衍生物(ATCC-90028),MIC值为0.05 mg / mL。化合物5由于其对A549细胞系的抑制作用和对NIH3T3细胞的低毒性而可以被确定为最有前途的针对A549癌细胞系的抗癌剂。
  • 【发现烯基硼酸作为神经保护剂,可影响涉及阿尔茨海默氏病的多个生物学靶标。】 复制标题 收藏 收藏
    DOI:10.1016/j.bmcl.2012.11.068 复制DOI
    作者列表:Jiménez-Aligaga K,Bermejo-Bescós P,Martín-Aragón S,Csákÿ AG
    BACKGROUND & AIMS: :Alkenylboronic acids have shown important biological activities that contribute to neuroprotection. We have determined their influence on the β-amyloid (βA) aggregation process, β-secretase and acethylcholinesterase activities on cell-free systems, on the redox and lipid peroxidation status, and on the vulnerability to apoptotic death in an APPswe neuroblastoma cell line, before and after hydrogen peroxide treatment. We have discovered that 2-arylvinylboronic acids and some of their esters possess a set of properties which makes them highly useful as neuroprotective agents affecting multiple biological targets involved in AD. These properties are not paralleled by the related 2-arylboronic acids.
    背景与目标: 烯基硼酸已显示出重要的生物活性,可促进神经保护作用。我们已经确定了它们对β-淀粉样蛋白(βA)聚集过程,β-分泌酶和乙酰胆碱酯酶活性对无细胞系统,氧化还原和脂质过氧化状态的影响,以及对APPswe神经母细胞瘤细胞株凋亡死亡的脆弱性的影响,过氧化氢处理前后。我们已经发现2-芳基乙烯基硼酸及其某些酯具有一系列特性,这使得它们非常有用地用作影响涉及AD的多个生物学靶标的神经保护剂。这些性能是相关的2-芳基硼酸无法比拟的。
  • 【设计,合成和评估白藜芦醇衍生物作为Aß(₁-₄_2)聚集抑制剂,抗氧化剂和神经保护剂。】 复制标题 收藏 收藏
    DOI:10.1016/j.bmcl.2012.09.105 复制DOI
    作者列表:Lu C,Guo Y,Li J,Yao M,Liao Q,Xie Z,Li X
    BACKGROUND & AIMS: :A series of novel resveratrol derivatives were designed, synthesised and evaluated as potential therapeutic agents for the treatment of Alzheimer's disease. Among these compounds, compound 7l, (E)-5-(4-(isopropylamino)styryl)benzene-1,3-diol, exhibited potent ß-amyloid aggregation inhibition activity, which was confirmed by a ThT fluorescence assay (71.65% at 20 μM) and transmission electron microscopy (TEM). Compound 7l also exhibited good antioxidant activity (4.12 Trolox equivalents in an oxygen radical absorbance capacity assay and a 37% reduction in reactive oxygen species in cells at 10 μM). The cytotoxicity analysis of compounds 7f, 7i, 7j and 7l indicated that these compounds have lower toxicities than resveratrol at 60 μM.
    背景与目标: :设计,合成和评估了一系列新型白藜芦醇衍生物,作为治疗阿尔茨海默氏病的潜在治疗剂。在这些化合物中,化合物7l,(E)-5-(4-(异丙基氨基)苯乙烯基)苯-1,3-二醇表现出强力的β-淀粉样蛋白聚集抑制活性,这可通过ThT荧光测定法证实(71.65%在20μM)和透射电子显微镜(TEM)。化合物7-1也表现出良好的抗氧化活性(在氧自由基吸收能力测定中为4.12 Trolox当量,并且在10μM下细胞中的活性氧减少了37%)。化合物7f,7i,7j和7l的细胞毒性分析表明,在60μM浓度下,这些化合物的毒性低于白藜芦醇。
  • 【八氢吡嗪[2,1-a:5,4-a']二异喹啉衍生物作为有效的抗癌药的生物学评价。】 复制标题 收藏 收藏
    DOI:10.1177/1010428317701641 复制DOI
    作者列表:Gornowicz A,Pawłowska N,Czajkowska A,Czarnomysy R,Bielawska A,Bielawski K,Michalak O,Staszewska-Krajewska O,Kałuża Z
    BACKGROUND & AIMS: :In this study, we evaluated the cytotoxic activity and antiproliferative potency of novel octahydropyrazin[2,1-a:5,4-a']diisoquinoline derivatives (1-7) in MCF-7 and MDA-MB-231 breast cancer cell lines. Annexin V binding assay and disruption of the mitochondrial potential were performed to determine apoptosis. The activity of caspases 3, 8, 9, and 10 was measured after 24 h of incubation with tested compounds to explain detailed molecular mechanism of induction of apoptosis. The results from experiments were compared with effects obtained after incubation in the presence of camptothecin and etoposide. Our study demonstrated that the most active compounds in both analyzed breast cancer cell lines were compounds 3 and 4. We also observed that all compounds induced apoptosis. We demonstrated the higher activity of caspases 3, 8, 9, and 10, which confirmed that induction of apoptosis is associated with external and internal cell death pathway. Our study revealed that the novel compounds in group of diisoquinoline derivatives are promising candidates in anticancer treatment by activation of both extrinsic and intrinsic apoptotic pathways.
    背景与目标: :在这项研究中,我们评估了新型八氢吡嗪[2,1-a:5,4-a']二异喹啉衍生物(1-7)在MCF-7和MDA-MB-231乳腺癌细胞中的细胞毒活性和抗增殖能力线。进行膜联蛋白V结合测定和线粒体电位破坏以确定细胞凋亡。在与被测化合物孵育24小时后,测定了胱天蛋白酶3、8、9和10的活性,以解释诱导凋亡的详细分子机制。将实验结果与在喜树碱和依托泊苷存在下孵育后获得的效果进行比较。我们的研究表明,在两种分析过的乳腺癌细胞系中,活性最高的化合物是化合物3和4。我们还观察到所有化合物均可诱导细胞凋亡。我们证明了胱天蛋白酶3,8,9和10较高的活动,这证实凋亡的诱导与外部和内部细胞死亡途径相关。我们的研究表明,通过激活外在和内在的凋亡途径,二异喹啉衍生物类中的新化合物有望成为抗癌治疗的候选药物。
  • 【用作抗癌剂的2-取代的4-(3',4',5'-三甲氧基苯基)-5-芳基噻唑的合成和生物学评估。】 复制标题 收藏 收藏
    DOI:10.1016/j.bmc.2012.10.001 复制DOI
    作者列表:Romagnoli R,Baraldi PG,Salvador MK,Camacho ME,Preti D,Tabrizi MA,Bassetto M,Brancale A,Hamel E,Bortolozzi R,Basso G,Viola G
    BACKGROUND & AIMS: :Antitumor agents that bind to tubulin and disrupt microtubule dynamics have attracted considerable attention in the last few years. To extend our knowledge of the thiazole ring as a suitable mimic for the cis-olefin present in combretastatin A-4, we fixed the 3,4,5-trimethoxyphenyl at the C4-position of the thiazole core. We found that the substituents at the C2- and C5-positions had a profound effect on antiproliferative activity. Comparing compounds with the same substituents at the C5-position of the thiazole ring, the moiety at the C2-position influenced antiproliferative activities, with the order of potency being NHCH(3) > Me > N(CH(3))(2). The N-methylamino substituent significantly improved antiproliferative activity on MCF-7 cells with respect to C2-amino counterparts. Increasing steric bulk at the C2-position from N-methylamino to N,N-dimethylamino caused a 1-2 log decrease in activity. The 2-N-methylamino thiazole derivatives 3b, 3d and 3e were the most active compounds as antiproliferative agents, with IC(50) values from low micromolar to single digit nanomolar, and, in addition, they are also active on multidrug-resistant cell lines over-expressing P-glycoprotein. Antiproliferative activity was probably caused by the compounds binding to the colchicines site of tubulin polymerization and disrupting microtubule dynamics. Moreover, the most active compound 3e induced apoptosis through the activation of caspase-2, -3 and -8, but 3e did not cause mitochondrial depolarization.
    背景与目标: 近年来,与微管蛋白结合并破坏微管动力学的抗肿瘤剂引起了相当大的关注。为了扩展我们对噻唑环作为康美他汀A-4中顺式烯烃的合适模拟物的认识,我们将3,4,5-三甲氧基苯基固定在噻唑核心的C4位。我们发现,在C2和C5位置的取代基对抗增殖活性具有深远的影响。比较噻唑环C5位上具有相同取代基的化合物,C2位上的部分影响抗增殖活性,效力顺序为NHCH(3)> Me> N(CH(3))(2) 。相对于C 2-氨基对应物,N-甲基氨基取代基显着提高了对MCF-7细胞的抗增殖活性。从N-甲基氨基到N,N-二甲基氨基的C2位增加的空间体积导致活性降低1-2 log。 2-N-甲基氨基噻唑衍生物3b,3d和3e是最有效的化合物作为抗增殖剂,其IC(50)值从低微摩尔到一位数纳摩尔,此外,它们还对耐多药细胞具有活性系过度表达P-糖蛋白。抗增殖活性可能是由于化合物与微管蛋白聚合的秋水仙碱位点结合并破坏了微管动力学而引起的。此外,活性最高的化合物3e通过激活caspase-2,-3和-8诱导细胞凋亡,但3e不会引起线粒体去极化。
  • 【植物心理药物的临床试验。】 复制标题 收藏 收藏
    DOI:10.1016/S0944-7113(97)80050-5 复制DOI
    作者列表:Schulz V,Hübner WD,Ploch M
    BACKGROUND & AIMS: :Phyto-psychopharmacological agents are extracts of plants with stimulating or calming effects on the central nervous system. Phyto-psycho-pharmacological agents are among the most commonly prescribed herbal medicines in Germany. The efficacy and harmlessness of some of the preparations have been established by high quality clinical trials. Between 1975 and 1992, a total of 34 clinical studies involving some 2326 patients were published on the effects of Ginkgo special extract EGb 761 and LI 1370; to date, 28 clinical trials in 2120 patients have been under-taken with alcoholic extracts of St. John's Wort. The therapeutic efficacy of kava and valerian extracts has been investigated in six and four controlled studies, respectively. In general, a high placebo effect is likely, which is why it is essential to include control groups in these studies. A considerable advantage over synthetic psychopharmacological agents is the low incidence of side effects, which in safety assessment studies is below 3%. The sharp increase in quality standards for clinical trials has meant that only a few preparations have undergone large scale testing programs in accordance with international guidelines. For other phyto-psychopharmacological agents, there is the danger that no further clinical trials will be undertaken due to the excessively high standards now demanded.
    背景与目标: :植物心理药物是对中枢神经系统具有刺激或镇定作用的植物提取物。植物心理药物是德国最常用的草药之一。某些制剂的功效和无害性已通过高质量的临床试验确定。 1975年至1992年间,共发表了34项临床研究,涉及2326例患者,研究了银杏特殊提取物EGb 761和LI 1370的作用。迄今为止,已对圣约翰草的酒精提取物进行了2120例患者的28项临床试验。卡瓦和缬草提取物的治疗功效已分别在六项和四项对照研究中进行了研究。通常,可能有很高的安慰剂作用,这就是为什么必须在这些研究中包括对照组的原因。相对于合成的心理药物而言,一个相当大的优势是副作用的发生率低,在安全性评估研究中,副作用低于3%。临床试验质量标准的急剧提高意味着,只有少数制剂按照国际准则进行了大规模的测试程序。对于其他植物心理药物,由于现在要求的标准过高,存在无法进行进一步临床试验的危险。
  • 【抗微管剂对草履虫细胞培养物生长的影响。】 复制标题 收藏 收藏
    DOI:10.1016/S0932-4739(11)80066-0 复制DOI
    作者列表:Pape R,Kissmehl R,Glas-Albrecht R,Plattner H
    BACKGROUND & AIMS: :Since there are no systematic studies available on the effects of anti-microtubule agents on ciliated protozoa, we screened a wide variety of such compounds for their effects on the growth of Paramecium tetraurelia cell cultures. Compounds tested include agents of widely different chemical composition and with reported effects on widely different cell types. We can differentiate between different drug effects: (a) Rotenone is the only agent without any recognisable effect, (b) Another group of compounds (including colchicine) requires very high concentrations, as compared to higher animal cells, i.e., rather close to a cytotoxic level; this group also includes tubulozole (unexpectedly without any difference between the cis- and the trans-stereoisomer). (c) A third group of drugs inhibits cell culture growth without any lethal effects (benzimidazoles, nocodazole, parbendazole; the [anti-]fungal antibiotic, griseofulvin; the herbicide, trifluralin). (d) Finally a group of agents are active in a concentration range also reported for plants (the herbicide, APM) or for higher animal cells (including the microtubule stabiliser, taxol) or for both (vinblastine, vincristine, triethyl lead), although they are cytotoxic at higher concentrations (like compounds of group [b]). Therefore, in particular compounds of group (c) and possibly of group (d) might be considered further on for a more detailed analysis of a possibly genuine anti-microtubular effect in Paramecium cells. Of particular interest may be nocodazole, parbendazole and trifluralin, since they can inhibit cell culture growth (over 24 h tested) in relatively low concentrations (comparable to other cell types) without any impairment of cell viability.
    背景与目标: :由于尚无关于抗微管剂对纤毛虫原虫影响的系统研究,因此我们筛选了多种此类化合物对草履虫草履虫细胞培养物生长的影响。测试的化合物包括化学成分差异很大的试剂,并且据报道对多种细胞类型具有影响。我们可以区分不同的药物作用:(a)鱼藤酮是唯一没有任何可识别作用的药物,(b)与较高的动物细胞相比,另一组化合物(包括秋水仙碱)需要很高的浓度,即接近细胞毒性水平;该组还包括微管唑(出乎意料的是,顺式和反式立体异构体之间没有任何区别)。 (c)第三类药物抑制细胞培养物的生长而没有任何致死作用(苯并咪唑,诺考达唑,苯达达唑; [抗]真菌抗生素,灰黄霉素;除草剂三氟拉林)。 (d)最后,一组试剂在植物(除草剂,APM)或高级动物细胞(包括微管稳定剂,紫杉醇)或两者(长春碱,长春新碱,三乙基铅)的浓度范围内均具有活性。它们在较高浓度下具有细胞毒性(如[b]组化合物)。因此,对于草履虫细胞中可能真正的抗微管作用的更详细的分析,可以进一步考虑组(c)以及可能的组(d)的化合物。尤其值得关注的是诺考达唑,帕苯达唑和三氟拉林,因为它们可以以相对低的浓度(与其他细胞类型相比)抑制细胞培养物的生长(测试超过24小时),而不会损害细胞活力。
  • 【HCV的抗病毒耐药性和直接作用抗病毒药。】 复制标题 收藏 收藏
    DOI:10.3851/IMP2426 复制DOI
    作者列表:Aloia AL,Locarnini S,Beard MR
    BACKGROUND & AIMS: :Direct-acting antiviral (DAA) agents specifically target viral proteins. Two DAAs have been already been approved for the treatment of HCV infection and many more are in development. DAA treatment of HCV infection, however, leads to the selection of viral variants (produced by the error-prone HCV polymerase) that are resistant to the DAA agent in use. The selection of DAA-resistant HCV variants has been studied extensively in vitro and in vivo. Common amino acid substitution sites in each of the non-structural proteins are associated with DAA-resistance: D168, A155, A156 and V36 in NS3 protease; L31 and Y93 in NS5A; S282, S96, P495, M423, M414 and C316 in NS5B. In this review we cover the basic principles of DAA resistance, summarise the available resistance data for the various classes of DAAs and discuss the potential of DAA combination therapy for overcoming DAA-resistance, resulting in major advances in the treatment of HCV.
    背景与目标: :直接作用抗病毒(DAA)剂专门针对病毒蛋白。已经批准了两种DAA用于治疗HCV感染,并且还有更多的药物正在开发中。但是,DAA对HCV感染的治疗导致选择对使用中的DAA剂具有抗性的病毒变体(由易出错的HCV聚合酶产生)。在体外和体内已经广泛研究了抗DAA的HCV变异体的选择。每种非结构蛋白中的常见氨基酸取代位点均与DAA耐药性相关:NS3蛋白酶中的D168,A155,A156和V36。 NS5A中的L31和Y93; NS5B中的S282,S96,P495,M423,M414和C316。在本综述中,我们涵盖了DAA耐药性的基本原理,总结了各种DAA耐药性的可用耐药性数据,并讨论了DAA联合疗法克服DAA耐药性的潜力,从而在HCV的治疗方面取得了重大进展。
  • 【普鲁卡因诱导的非洲爪蟾卵母细胞的成熟是由M期促进因子的瞬时激活介导的。】 复制标题 收藏 收藏
    DOI:10.1017/s0967199400003518 复制DOI
    作者列表:Flament S,Bodart JF,Browaeys E,Bertout M,Rousseau A,Gannon J,Vilain JP
    BACKGROUND & AIMS: We have recently shown that the incubation of Xenopus laevis oocytes in procaine-containing solutions induced germinal vesicle breakdown without white spot formation and, in some cases, with the appearance of spindle and chromosomes in the cytoplasm. The present study was performed to determine whether M-phase promoting factor was involved in this unusual maturation. Procaine failed to induce maturation in the presence of 6-dimethylamino purine or roscovitine, which are both known to inhibit p34cdc2 kinase. Histone H1 kinase activity was detected in procaine-treated oocytes but it was always lower than in progesterone-treated controls. A shift in p34cdc2 was observed in oocytes that had been exposed to procaine for 16 h, but it was not detected in those exposed for 24 h. Finally, cytoplasm transfer experiments demonstrated that the maturation promoting activity that occurred in oocytes incubated in procaine for 16 h could induce maturation of recipient stage VI oocytes. This transferable activity was weaker than that from progesterone-treated controls since only 30% of the recipients underwent germinal vesicle breakdown and only a few spindles were observed, which were not always correctly located. Taken together these results demonstrate that M-phase promoting factor is involved in the procaine maturing effect despite some differences compared with progesterone-treated oocytes which might explain the particular type of maturation induced by this substance. The discovery of the mechanisms by which procaine is able to activate M-phase promoting factor might now help in the understanding of some steps in progesterone-induced maturation that have still to be elucidated.

    背景与目标: 我们最近发现,非洲爪蟾卵母细胞在含有普鲁卡因的溶液中的孵育可诱导发芽囊泡破裂,而不会形成白点,在某些情况下,在细胞质中还会出现纺锤体和染色体。进行本研究是为了确定M期促进因子是否参与了这种异常的成熟。在6-二甲基氨基嘌呤或roscovitine的存在下,普鲁卡因无法诱导成熟,这两种物质均已知抑制p34cdc2激酶。在经普鲁卡因处理的卵母细胞中检测到组蛋白H1激酶活性,但始终低于经孕激素处理的对照组。在已暴露于普鲁卡因16 h的卵母细胞中观察到p34cdc2发生变化,但在暴露24 h的卵母细胞中未检测到。最后,细胞质转移实验表明,在普鲁卡因中孵育16 h的卵母细胞中发生的促进成熟的活性可以诱导受体VI期卵母细胞的成熟。这种可转移的活性比黄体酮治疗的对照弱,因为只有30%的接受者经历了生小泡破裂,并且仅观察到少数纺锤体,但并不总是正确定位。这些结果加在一起表明,尽管与孕酮处理的卵母细胞相比有一些差异,但M期促进因子参与了普鲁卡因的成熟作用,这可能解释了该物质诱导的特定类型的成熟。普鲁卡因能够激活M期促进因子的机制的发现,现在可能有助于了解孕激素诱导的成熟的某些步骤,这些步骤仍有待阐明。

  • 【与已建立的人子宫内膜上皮和基质细胞系共培养对精子运动特性的影响。】 复制标题 收藏 收藏
    DOI:10.1093/humrep/12.6.1197 复制DOI
    作者列表:Guerin JF,Merviel P,Plachot M
    BACKGROUND & AIMS: The effects of co-culture of human spermatozoa with human immortalized endometrial cells - epithelial or stromal - on sperm movement characteristics, including hyperactivation, were studied using computer-assisted sperm analysis (CASA). Epithelial and stromal cell types could be separated following 8-10 days of culture of endometrial cells originating from human biopsies. Both cell types were immortalized by the SV 40 large T antigen. Co-incubation of sperm with epithelial and stromal monolayers enhanced the rate of hyperactivation24.9% (P <0.05) and 17.8% (P = 0.05) versus 9.5% as control, respectively, whereas the majority of motility parameters remained unchanged. Conditioned media had no effect upon sperm parameters, including hyperactivation. Co-incubation with either monolayer was able to maintain sperm motility over a longer period than incubation in control medium alone.

    In four patients whose spermatozoa did not exhibit hyperactivation, co-incubation with epithelial cells, but not conditioned medium, allowed normal rates of hyperactivation (range6.9-15.6%).

    背景与目标: 使用计算机辅助精子分析(CASA)研究了人类精子与人类永生化子宫内膜细胞-上皮或基质共培养对精子运动特征(包括过度活化)的影响。在培养源自人类活组织检查的子宫内膜细胞后8-10天,可以分离上皮和基质细胞类型。两种细胞类型都可以通过SV 40大T抗原获得永生。将精子与上皮和基质单层共同孵育可提高超活化率,分别为对照组的24.9%(P <0.05)和17.8%(P = 0.05),而对照组为9.5%,而大多数运动参数保持不变。条件培养基对精子参数没有影响,包括过度激活。与单独在对照培养基中孵育相比,与任一单层一起共同孵育能够在更长的时间内维持精子活力。

    在四名精子未表现出过度激活的患者中,与上皮细胞共同孵育,但不与条件培养基共同孵育,允许正常的过度激活率(范围6.9-15.6%)。

  • 【体外星形胶质细胞的成熟改变了神经突向外生长的程度和分子基础。】 复制标题 收藏 收藏
    DOI:10.1016/0012-1606(90)90204-v 复制DOI
    作者列表:Smith GM,Rutishauser U,Silver J,Miller RH
    BACKGROUND & AIMS: :In the developing mammalian central nervous system astrocytes have been proposed as an important substrate for axon growth. In the adult central nervous system following injury, astrocytes are a major component of the gliotic response which has been proposed to block axon growth. Experimental transplantation studies using cultured astrocytes have suggested that immature but not mature cultured astrocytes have the capacity to support axon outgrowth when transplanted into the adult rodent CNS. These observations suggest that astrocyte maturation is accompanied by changes in the functional capacity of these cells to support axon outgrowth. To determine whether this functional change reflects an intrisic astrocyte property, the extent and molecular bases of neurite outgrowth from embryonic rat cortical and chick retinal neurons on cultures of purified immature and mature astrocytes have been compared in vitro. The rate and extent of neurite outgrowth from both neuronal populations are consistently greater over the surface of immature than over the surface of mature astrocytes. Furthermore, antibodies to NCAM and G4/L1 significantly reduce neurite outgrowth on immature but not mature astrocytes, while antibodies to the integrin B1 receptor reduced outgrowth on both immature and, to a lesser extent, mature astrocytes. These results suggest that in vitro mature astrocytes have a reduced capacity and different molecular bases for supporting neurite outgrowth compared to immature astrocytes and are consistent with the proposal that functional changes during astrocyte maturation may partially contribute to regulating axon growth in the mammalian CNS.
    背景与目标: :在发展中的哺乳动物中枢神经系统中,星形胶质细胞已被提议作为轴突生长的重要底物。在损伤后的成年中枢神经系统中,星形胶质细胞是神经胶质反应的主要成分,已被提议阻断轴突的生长。使用培养的星形胶质细胞进行的实验性移植研究表明,当移植到成年啮齿动物中枢神经系统中时,未成熟但不是成熟的培养星形胶质细胞具有支持轴突生长的能力。这些观察结果表明,星形胶质细胞的成熟伴随着这些细胞支持轴突生长的功能能力的变化。为了确定这种功能变化是否反映了内在的星形胶质细胞特性,在体外比较了纯化的未成熟和成熟的星形胶质细胞培养物中胚胎大鼠皮层和鸡视网膜神经元神经突生长的程度和分子基础。来自两个神经元群体的神经突向外生长的速率和程度在未成熟的表面上始终比在成熟的星形胶质细胞表面上大。此外,针对NCAM和G4 / L1的抗体可显着减少未成熟但未成熟的星形胶质细胞上的神经突生长,而针对整联蛋白B1受体的抗体则可减少未成熟的星形胶质细胞(在较小程度上)减少的星形胶质细胞的生长。这些结果表明,与不成熟的星形胶质细胞相比,体外成熟的星形胶质细胞具有降低的能力和支持神经突生长的不同分子基础,并且与在星形胶质细胞成熟过程中功能改变可能部分有助于调节哺乳动物中枢神经系统中轴突生长的提议相一致。

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