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1.
海洋微生物因其特殊的生存环境而具有产生新型生物活性物质的巨大潜力,从海洋微生物中筛选药用活性物质已成为当今研究的热点.近年来,研究者们从海洋真菌中分离鉴定出了大量结构新颖的次级代谢产物,这些化合物表现出良好的抗肿瘤、抗菌或抗病毒等生物活性.本文对2010年来研究者们从海洋真菌中分离得到的部分次级代谢产物及相关生物活性的研究进展进行了综述,以期为海洋真菌天然药物的研究与开发提供借鉴和指导.  相似文献   

2.
目的:对从黄海海滨土壤中分离得到的菌株进行鉴定并研究其次级代谢产物的抗菌、抗肿瘤活性和结构信息。方法:分析分离得到的菌株的16srDNA、形态等特征,确定其种属以及研究其次级代谢产物(BSC)的抗菌抗肿瘤活性,并对BSC的结构进行了初步分析。结果:根据该株菌的16s rDNA、形态等特征,确定其为芽胞杆菌属,其次级代谢产物BSC具有一定的抗菌抗肿瘤活性,其分子式为C48H94O19。结论:分离得到的菌株为芽胞杆菌属,其次级代谢产物BSC具有一定的抗菌、抗肿瘤活性,是潜在的抗生素类药物。  相似文献   

3.
微生物次级代谢产物结构多样、种类丰富,是新药发现的重要来源。微生物次级代谢产物由特定生物合成基因簇编码合成,通常与微生物的生长繁殖无关。由于实验室可培养微生物的数量较少,而且多数可培养微生物存在基因簇沉默的现象,严重阻碍了微生物来源药物的研究和开发。微生物生物合成基因簇的异源表达及生物合成相应的次级代谢产物已逐渐成为发现新颖活性化合物的有效手段之一。作为研究微生物次级代谢产物的重要工具,基于TAR(transformation associated recombination)克隆技术的异源表达策略可实现绝大多数基因簇的完整异源表达。本文从TAR克隆技术的原理、应用和策略改进3个方面,总结了基于TAR克隆技术的微生物次级代谢产物异源生物合成的研究进展,为研究和开发新型微生物来源药物提供方法学借鉴。  相似文献   

4.
近年国内海洋微生物代谢产物研究概况   总被引:2,自引:0,他引:2  
海洋微生物代谢产物是新药及其先导结构的一个重要来源,相关研究近来倍受关注。本文简要综述近年国内海洋微生物代谢产物的研究概况。  相似文献   

5.
目的探讨含氮大环内酯免疫抑制剂FK506等不同产生菌之间进化关系及其次级代谢产物合成基因的水平转移。方法克隆不同产生菌的16SrRNA基因以及FK506等代谢产物羟化酶、甲基转移酶基因,采用Mega程序应用不同模型构建菌株系统进化树和合成酶分子进化树。结果代谢产物结构差异越大,其合成酶基因的进化关系越远,但是其产生菌的进化关系却可能较为接近,产生菌的进化关系与代谢产物合成酶分子进化关系不同步。结论此类次级代谢产物合成基因并不是菌株本身固有的,而是在菌株进化过程中同属不同种微生物之间发生基因水平转移获得的。  相似文献   

6.
抗生素抗性筛选在微生物菌株选育中的作用   总被引:8,自引:2,他引:8  
选育优良微生物菌株对微生物药物研发尤其是对微生物制药实现产业化具有至关重要的意义。抗生素抗性筛选基于微生物对抗生素产生抗性,因其实验操作简便、效果显著而在有用微生物菌株选育中得到广泛应用。在微生物药物领域抗生素抗性筛选技术主要用来筛选获取高产菌株,但近来发现微生物的抗生素抗性突变可赋予突变株新生次级产物的代谢生产能力,因此在拓展药源微生物资源领域具有潜在应用价值。本文主要综述抗生素抗性筛选在微生物菌株选育中的作用以及相关新近研究进展。  相似文献   

7.
微生物次级代谢产物因其显著的生物活性一直是新药发现与开发的重要来源之一,激增的基因组信息表明,链霉菌中存在着巨大的生物合成潜力。但目前从链霉菌中挖掘的具有新骨架或新结构单元的活性次级代谢产物数量远低于生物合成基因簇的数量,原因主要在于很多生物合成基因簇在常规实验条件下表达微弱或转录沉默。从预测生物合成基因簇的生物信息学工具入手,本文重点阐述了在天然宿主和异源宿主中激活链霉菌沉默生物合成基因簇的经典方法和最新策略,包括转录因子诱捕、报告子导向的高通量筛选以及多重CRISPR-TAR等,为挖掘链霉菌新型次级代谢产物提供了方法学参考。  相似文献   

8.
微生物天然产物的生物合成是一个从基因到化合物的过程。微生物基因组内未被发掘的孤儿或沉默途径所编码的新型次级代谢产物的合成潜力远远超过现已发现的代谢产物数量。微生物基因组大规模测序的广泛开展,为天然产物的发现和研究提供了新的研究领域和契机。本文主要介绍基于微生物基因组序列的新型天然产物的发现策略及其研究进展。可以预计,随着实验技术的不断发展,采用基于基因的药物发现模式可以充分发掘微生物产生天然产物的潜力,微生物基因组内的孤儿或沉默途径编码的未知代谢产物将成为新药开发的重要源泉。  相似文献   

9.
秦立新 《中国乡村医生》2010,12(17):200-200
抗生素(antibiotics)是由微生物(包括细菌、真菌、放线菌属)或高等动植物在生活过程中所产生的具有抗病原体或其他活性的一类次级代谢产物,能干扰其他生活细胞发育功能的化学物质。现临床常用的抗生素有微生物培养液中提取物以及用化学方法合成或半合成的化合物。目前已知的天然抗生素不下万种。  相似文献   

10.
目的 探讨人工诱变对海洋牡蛎共生真菌代谢产物的影响.方法 采用硫酸二乙酯(DES)、紫外、微波等方法对真菌Alternaria alternata(YS-4)进行诱导突变,采用Ellman法、DPPH自由基清除法和滤纸片法研究突变菌株代谢产物抑制AChE、抗氧化和抗菌活性.结果 通过人工诱变得到6株稳定遗传的菌株,分别为聚多曲霉(Aspergillus sydowii)、烟曲霉(Aspergillus fumigatus)、皮落青霉(Penicillium crustosum)、指状拟青霉(Paecilomyces dactylethromorphus)、糙刺篮状菌(Talaromyces sp.)和青霉菌(Penicillium sp.).与野生菌株相比,突变菌株YB-1和YB-17的代谢产物更为丰富,且其粗提物具有较强的抑制AchE活性和清除DPPH自由基作用,抑制率分别为55.86%、60.31%和41.72%、36.85%;YB-17、YB-23和YB-24对金黄色葡萄球菌具有一定的抑制作用.结论 本研究通过诱导突变得到了具有稳定遗传且代谢产物生物活性较好的菌株,为进一步充分挖掘结构丰富、活性良好的次级代谢产物奠定基础.  相似文献   

11.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

12.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

13.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

14.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

15.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

16.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Journal of Nanjing Medical University (English Edition) JNMU, sponsored by Nanjing Medical University, was established in 1987. It is a bimonthly comprehensive English medical journal published locally and abroad.Since 2007, Journal of Nanjing Medical University (English Edition )was granted Elsevier the full publishing and distribution rights worldwide for the Electronic Edition, excluding the People's Republic of China.  相似文献   

19.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

20.
Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P< 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P< 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.  相似文献   

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