冷泉来源诺卡氏菌OUCLQ19-35-1次级代谢产物的研究

目的 探究深海冷泉来源微生物的次级代谢产物产生能力,从中挖掘具有抗多重耐药(multi-drug resistant, MDR)菌活性的次级代谢产物,为新药研发提供化合物实体。方法 采用稀释涂布法分离纯化深海冷泉海泥样品中的放线菌,通过琼脂扩散法筛选具有抗MDR菌活性的放线菌;基于16S rRNA基因片段序列分析和系统进化树构建初步确定目标放线菌种属;对目标放线菌进行大规模发酵,采用有机溶剂萃取、反相硅胶柱层析、半制备高效液相等分离手段对发酵产物进行分离纯化,利用NMR、MS等波谱学技术并结合文献对化合物进行结构鉴定,然后对化合物进行抗MDR菌活性测试。结果 从深海冷泉中筛选到一株具有抗MDR菌Micrococcus luteus ML01和Staphylococcus aureus CCARM3090活性的放线菌OUCLQ19-35-1,16S rRNA序列及系统进化树分析初步确定其为Nocardiopsis synnemataformans;从其发酵产物中分离得到3个化合物,分别为questiomycin A(1)、1,6-dihydroxyphenazine(2)和5a,6,11a,12-tetrahydro-5a,11a-dimethyl[1,4]benzoxazino[3,2-b][1,4]benzoxazine(3);活性结果显示,化合物1-3均无抗MDR菌活性,但其所在的组分有抑菌活性。结论 从深海冷泉筛选得到一株诺卡氏菌OUCLQ19-35-1,其能够产生抗MDR菌的活性次级代谢产物,具有潜在的应用价值,但其活性成分待进一步的确定。     

深海冷泉链霉菌OUCLQ19-3次级代谢产物的研究

目的 探究深海冷泉来源微生物产生丰富次级代谢产物的潜力,挖掘具有抗多重耐药(multi-drug resistant, MDR)菌活性的次级代谢产物,为新型海洋药物研发提供先导化合物。方法 采用大规模发酵积累粗提物,利用有机溶剂萃取、C18反相硅胶开放柱层析、半制备高效液相等分离手段对发酵产物进行分离纯化,通过MS、NMR数据以及文献比对进行化合物的结构鉴定,进而对化合物进行抗MDR菌活性测试。结果 从深海冷泉来源链霉菌Streptomyces sp. OUCLQ19-3发酵产物中分离得到2个xiamycin类化合物,分别为xiamycin B(1)和xiamycin A(2);活性结果显示,化合物1和2均无抗MDR菌活性。结论 深海冷泉来源链霉菌Streptomyces sp. OUCLQ19-3能够产生一系列丰富的次级代谢产物,具有潜在的药用价值,其活性化合物有待进一步挖掘。     

多效调控基因wblAyo对海洋链霉菌Streptomyces youssoufiensis OUC6819次级代谢产物及形态分化的影响

目的 激活南海红树林来源的链霉菌Streptomyces youssoufiensis OUC6819中不表达或表达水平低的隐性基因簇,进一步挖掘新颖的次级代谢产物。方法 采用PCR-targeting策略敲除WhiB-like（Wbl）家族的wblAyo基因,通过HPLC分析野生株和突变株发酵产物的差异,检测发酵液粗提物和C18开放柱层析组分对5种多重耐药（MDR）菌（Staphylococcus aureus CCARM 3090, Salmonella typhimurium CCARM 8250, Escherichia coli CCARM 1009, Enterococcus faecium CCARM 5203,Enterococcus faecalis CCARM 5172）的抑制活性,通过固体平板实验和光学显微镜观察链霉菌形态分化的改变。结果 得到了正确的ΔwblAyo阻断突变株,HPLC分析结果表明：与野生株相比,突变株中化合物峰1和2分别提高了15.6和9.3倍;突变株发酵液粗提物和组分11对E. faecium CCARM 5203,E. faecalis CCARM 5172和S. aureus CCARM 3090的抗菌活性与野生株相比明显提高,而且突变株丧失了产生孢子的能力。结论 wblAyo参与了S. youssoufiensis OUC6819的次级代谢和形态分化过程。wblAyo的阻断激活了S. youssoufiensis OUC6819中抗MDR菌活性次级代谢产物的产生,为继续挖掘活性化合物提供了必要基础,还为其他海洋链霉菌中隐性基因簇的激活提供了参考。     

深海链霉菌SCSIO 1071中聚酮合酶基因簇Cluster 46编码产物探究

目的 对南海深海来源链霉菌Streptomyces olivaceus SCSIO 1071中新颖I型聚酮合酶基因簇Cluster 46及其编码产物进行探究。方法 通过生物信息学手段对基因簇Cluster 46的基因组成进行分析；采用PCR-targeting策略构建聚酮合酶基因orf27和LuxR家族转录调控基因orf46双交换阻断突变株；通过高效液相色谱法(high performance liquid chromatography，HPLC)分析野生株和突变株发酵产物的差异,检测粗提物对3株多重耐药(multiple drug resistant, MDR)菌(Staphylococcus aureus CCARM 3090、Enterococcus faecalis CCARM 5172、Enterococcus faecium CCARM 5203)的抑菌活性。结果 得到了Δorf27和Δorf46双交换阻断突变株；HPLC分析结果表明,相比较野生株,Δorf27和Δorf46突变株中化合物峰1-10不再产生；突变株发酵液粗提物对3株MDR菌抑菌活性较野生株明显降低；液相色谱-质谱（liquid chromatograph mass spectrometer，LC-MS）数据和紫外（ultraviolet，UV）数据表明化合物峰1-10可能为dixiamycins类化合物。结论 orf27和orf46的阻断间接影响了具有抗MDR菌活性的化合物峰1-10的产生,为挖掘S. olivaceus SCSIO 1071中新颖活性次级代谢产物奠定了基础。     

海洋链霉菌Streptomyces sp. rssa2的次生代谢产物及其抗菌活性研究

目的 研究1株珊瑚来源的共附生链霉菌菌株Streptomyces sp. rssa2的次生代谢产物及其抗菌活性。方法 采用正相硅胶柱色谱、ODS反相硅胶柱色谱、Sephadex LH-20凝胶柱色谱以及半制备高效液相色谱（HPLC）等手段对rssa2的发酵产物进行分离纯化，通过核磁、质谱数据并结合文献数据鉴定化合物结构；通过滤纸片法和稀释法对化合物的抗菌活性进行测定。结果 从海洋链霉菌Streptomyces sp. rssa2的液体麦芽提取物培养基发酵产物中分离得到3个主要成分，其结构分别鉴定为大环内酯类化合物aldgamycin G(1)、aldgamycin E(2)、swalpamycin(3)。抗菌活性测试结果显示，化合物1～3均对溶藻弧菌（Vibrio alginolyticus）的生长具有弱抑制活性。结论 化合物1～3均为首次从珊瑚共附生链霉菌中分离获得，并且发现它们具有一定程度的抗菌活性，具有潜在的研究价值。     

通过阻断GntR家族调控基因ygrA挖掘海洋链霉菌Streptomyces sp. OUC6819中抗MDR菌活性次级代谢产物

激活南海红树林来源链霉菌Streptomyces sp.OUC6819菌株中不表达或表达量低的隐性生物合成基因簇,挖掘具有优良多重耐药菌（MDR）抗菌活性的次级代谢产物。方法 通过生物信息学分析推测Streptomyces sp.OUC6819基因组中可能的GntR家族调控子,采用PCR-targeting策略敲除其中的ygrA基因,HPLC分析突变株和野生株的发酵产物的差异,并比较粗提物对5株MDR菌抑制活性。结果 HPLC分析结果表明与野生株相比,突变株中化合物1和化合物2产量分别产量提高了9倍和7倍;突变株发酵液粗提物对其中3株MDR菌抑制活性较野生株明显提高。结论 通过阻断GntR家族调控子ygrA激活了Streptomyces sp.OUC6819菌株中具有抗MDR菌活性次级代谢产物合成基因簇的表达,为从中发掘新的抗MDR菌抗生素奠定了必要基础;同时,将为其他海洋链霉菌中隐性基因簇的激活提供重要参考。     

海鞘来源放线菌Streptomyces pratensis SCSIO LCY05中Anthracimycin类化合物及其抗菌活性研究

目的 研究来源于海鞘的放线菌Streptomyces pratensis SCSIO LCY05产生的抑菌活性物质。 方法 采用硅胶柱色谱、中压制备色谱、半制备HPLC等方法对其发酵产物分离纯化,经HR-ESI-MS、NMR以及X-ray单晶衍射等方法确定化合物的结构;采用微量二倍稀释法对化合物进行抗菌活性评价。 结果 从发酵产物中分离鉴定了3个化合物：anthracimycin C(1)、anthracimycin(2)和anthracimycin B(3),结构得到X-ray单晶衍射的确证,其中化合物1为新化合物。经抗菌活性测定,化合物2和3对6株革兰氏阳性菌具有显著的抑制活性,最小抑菌浓度(MIC)值在0.0675-0.25 μg/mL之间,并首次发现化合物2和3对藤黄微球菌和模仿葡萄球菌生长抑制活性良好。 结论 海洋共附生微生物是天然活性物质的重要来源,从海鞘来源的S. pratensis SCSIO LCY05中分离获得具有抗菌活性的anthracimycin类化合物可作为良好的抗菌药物先导化合物。     

海南海桑内生真菌Bionectria ochroleuca HHS111023次生代谢产物的研究

目的 研究中国特有红树植物海南海桑内生真菌Bionectria ochroleuca HHS111023的次生代谢产物及其生物活性。方法 利用多种柱色谱技术对次生代谢产物进行分离纯化;通过核磁与质谱数据分析结合理化常数及文献比对,鉴定化合物的结构;分别采用纸片琼脂扩散法和MTT法对化合物的抗菌活性和细胞毒活性进行测试。结果 从海南海桑内生真菌Bionectria ochroleuca HHS111023的次生代谢产物中分离鉴定了7个化合物：Lasiodiplodin (1)、(R)-de-O-methyllasiodiplodin (2)、(5S)-5-hydroxylasiodiplodin (3)、 (5R)-5-hydroxylasiodiplodin (4)、methyl (E)-11,12,15-trihydroxyoctadec-13-enoate (5)、对羟基苯乙醇 (6)、对羟基苯乙酸甲酯 (7)。化合物1和2分别对白色念珠菌和青枯雷尔氏菌具有抗菌活性,且分别对SGC-7901和K-562具有体外细胞毒活性。结论 化合物1 ~ 4为首次从淡色生赤壳菌Bionectria ochroleuca次生代谢产物中分离得到,化合物5为首次分离自微生物次生代谢产物;海南海桑内生真菌Bionectria ochroleuca HHS111023能产生具有抗菌和细胞毒活性的化合物。     

海洋源放线菌Streptomyces sp.SCSIO 10428中吩嗪生物碱类抗生素的分离鉴定

目的对从广西北海斜阳岛海域沉积物中分离的1株海洋源放线菌Streptomyces sp.SCSIO 10428进行次级代谢产物及活性研究。方法对海洋源放线菌Streptomyces sp.SCSIO 10428的发酵产物进行有机溶剂萃取,利用硅胶、凝胶柱层析等手段纯化次级代谢产物,通过波谱数据分析及文献比较对化合物进行结构鉴定,对化合物进行了抗菌、卤虫致死以及抗氧化活性评价。结果从海洋源放线菌Streptomyces sp.SCSIO10428发酵产物中分离得到3个生物碱类化合物,其结构分别鉴定为1-甲氧基吩嗪(1),1-羟基吩嗪(2),吩嗪-1-羧酸(3);活性结果显示化合物1~3对白色念珠...     

海洋链霉菌Streptomyces sp. S598中抗菌活性产物的研究

目的 对海洋链霉菌Streptomyces sp. S598固体发酵提取物的抗菌成分进行研究。方法 采用葡聚糖凝胶Sephadex LH-20、反相柱色谱、硅胶柱层析及半制备HPLC等方法分离纯化该菌株的活性次级代谢产物,并通过ESI-MS、NMR等波谱技术结合文献对比鉴定其结构。结果 从10L固体发酵提取物中分离得到5个单体化合物,分别鉴定为缬氨霉素(1)、二活菌素(2)、亚油酸(3)、亚油酸甲酯(4)和油酸(5)。结论 海洋链霉菌Streptomyces sp. S598能代谢产生具有多种生物活性的化合物。化合物1对MRSA 28300和白念珠菌(ATCC10231)的MIC为1μg/mL,化合物2具有较强的广谱抗细菌活性,对肺炎链球菌、流感嗜血菌的MIC为0.125μg/mL,尤其具有显著的抗MRSA的活性,对MRSA     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.