Pleiotropic changes in the activities of extracellular toxins of Pseudomonas aeruginosa protease-deficient mutants

Protease-deficient mutants of Pseudomonas aeruginosa obtained by ethyl methane sulphonate treatment were found to show pleiotropic effect on various extracellular toxin activities. Of eight mutants five were completely deficient in lecithinase and four in collagenase activity. The decreased hemolytic activity was obtained in five mutants and enterotoxin activity in seven mutants as compared to parent strain.     

7株放线菌在辣椒根部定殖及对辣椒叶片PAL与PPO活性的影响

采用盆栽接种试验、平皿涂抹法测数及常规酶活测定法研究了7株拮抗性放线菌在辣椒根部的定殖能力及接种24d对辣椒叶片苯丙氨酸解氨酶（PAl。）与多酚氧化酶活性（PPO）的诱导效应。结果表明：（1）供试7株放线菌单独接种均不能在辣椒根内定殖,但与辣椒疫霉P3混合接种时有5株可定殖;供试放线菌在辣椒根部的定殖能力与其体外平皿试验中产生的的拈抗圈大小基本无关;可定殖放线菌的定殖密度随时间延长而降低,至40d时均无活菌检出。（2）在放线菌单接处理中,5株菌接种后可诱导辣椒叶片PAL,活性提高,全部供试菌均能诱导PPO活性提高,其中可使两种酶同步提高的有5株菌;在放线菌＋P3混接处理中,有6株接种后可诱导PAL,活性提高,5株菌能诱导PPO活性提高,其中可使两种酶同步提高的有4株菌;在接入放线菌时同时混接辣椒疫霉,能增强2株供试放线菌对辣椒叶片PAL活性及6株供试放线菌对辣椒叶片PPO活性的诱导作用;供试放线菌的定殖能力与辣椒叶片PAL及PPO活性变化无明显规律性关系。     

On the loss of uricolytic activity during primate evolution--I. Silencing of urate oxidase in a hominoid ancestor

Urate oxidase activity is not detectable in liver homogenates from the gibbon, orangutan, chimpanzee, gorilla and human. Liver homogenates from five genera of Old World and two genera of New World monkeys have easily detectable levels of urate oxidase activity. There is no evidence for extant detectable intermediate steps in the loss of urate oxidase activity in the hominoids. Urate oxidase activity from Old World and New World monkeys is stable, a simple observation which debunks a long-standing myth. Urate oxidase activity was silenced in an ancestor to the five living genera of hominoids after divergence from the Old World monkeys.     

Histophysiologic aspects of the remnant intestine of rats subjected to partial resection of the small intestine

The effect of small bowel resection on the morphology, mucous secretion and alkaline phosphatase activity of the remnant intestine was studied five months after surgical operation. Distal small bowel resection produced hyperplasia and infiltration of lymphocytes. The intestinal neutral and acid mucosubstances, and the alkaline phosphatase activity were increased in resected animals, whilst the sulphomucins content of goblet cells was unaltered. The serum alkaline phosphatase activity two and five months after resection was also increased.     

苯并异噻唑啉酮类化合物的生物活性研究

对合成的5种苯并异噻唑啉酮类化合物进行了生物活性研究。抑菌试验结果表明,化合物a与化合物b对大肠杆菌最小抑菌浓度为12.5mg/L。对金黄色葡萄球菌都表现出良好的抑菌活性。对亚心形扁藻,蛋白核小球藻,球等鞭金藻,化合物都有抑制其生长的活性,亚心形扁藻耐受性最高,球等鞭金藻的耐受性最低,蛋白核小球藻的耐受性居中。     

昆仑雪菊提取物对α- 葡萄糖苷酶的抑制作用

目的:探讨昆仑雪菊提取物对α-葡萄糖苷酶的抑制活性。方法:将昆仑雪菊干燥花序粉碎,分别用水提法和乙醇法制备5种提取物。采用α-葡萄糖苷酶体外活性抑制模型,测定昆仑雪菊的5种提取物对α-葡萄糖苷酶的抑制活性。结果:这5种提取物对α-葡萄糖苷酶活性有较强的抑制作用,抑制活性均高于阿卡波糖。其中提取物Ⅰ的抑制活性最强,IC50=28.2 mg/L。结论:昆仑雪菊提取物具有较高的α-葡萄糖苷酶抑制活性,提示昆仑雪菊在抗糖尿病产品开发方面具有很好的应用前景。     

Imaging activity of neuronal populations with new long-wavelength voltage-sensitive dyes

We have assessed the utility of five new long-wavelength fluorescent voltage-sensitive dyes (VSD) for imaging the activity of populations of neurons in mouse brain slices. Although all the five were capable of detecting activity resulting from activation of the Schaffer collateral-CA1 pyramidal cell synapse, they differed significantly in their properties, most notably in the signal-to-noise ratio of the changes in dye fluorescence associated with neuronal activity. Two of these dyes, Di-2-ANBDQPQ and Di-1-APEFEQPQ, should prove particularly useful for imaging activity in brain tissue and for combining VSD imaging with the control of neuronal activity via light-activated proteins such as channelrhodopsin-2 and halorhodopsin.     

The C-terminus of glycosylphosphatidylinositol-specific phospholipase D is essential for biological activity

Glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) (EC 3.1.4.50) from mammalian serum is a 115 kDa glycoprotein consisting of 816 amino acids. We found that C-terminal deletions of only two to five amino acids reduced GPI-PLD enzymatic activity by roughly 70% as compared to wild-type protein. C-terminal deletions of more than five amino acids resulted in a complete loss of GPI-PLD enzymatic activity. Point mutations at position 811 indicate that Tyr-811 may play a major role in maintaining the biological activity of GPI-PLD.     

几种常用中草药抗氧化活性研究(英文)

当归、黄芪、银杏叶、益母草、野甘草是中国传统中药材,几千年来一直为中国人民所认可,在中国和世界都具有重要的科研和药用价值。本研究采用HO·清除及对肝微粒体和亚油酸脂质过氧化抑制的方法,测定五种草药精油和水煮提取物的抗氧化活性;采用Folin—Ciocalteu试剂法测定它们的总酚含量;用肝细胞体外培养法测定它们的细胞毒性并对它们的作用机制进行分析。结果发现五种草药提取物都具有一定的抗氧化活性,尤其是益母草、野甘草、银杏叶的水煮提取物活性较强,其抗氧化活性与总酚含量存在较好的线形关系。此外,本论文还为研究这些草药的一些抗病机制提供参考依据。     

Development of nuclease activity in cotyledons of Pisum sativum L.

Summary The RNA content of pea cotyledons shows little change during the first five days of germination at 22°C. From day five onwards there is a rapid net degradation of RNA, which continues until day thirteen. The DNA content of the cotyledons increases slightly during the first nine days of germination, after which there is a net decrease. Acid and alkaline ribonuclease activities increase markedly between day one and day five, and then decline between day five and day nine. There is a second increase in the activities of both enzymes from day nine onwards. Soluble deoxyribonuclease activity exhibits a single peak, seven days after the onset of germination. The first increase in acid ribonuclease activity is only partially inhibited by cycloheximide at concentrations which severely inhibit protein synthesis.     

Antimicrobial Activity of 8-Quinolinols, Salicylic Acids, Hydroxynaphthoic Acids, and Salts of Selected Quinolinols with Selected Hydroxy-Acids

Seventy-seven compounds were screened by the disc-plate method against strains of five bacteria and five fungi. A new constant was proposed to describe the antimicrobial activity of a compound in a defined system of organisms. This constant includes not only the inhibitory level of activity of the material but also the number of organisms inhibited. This constant, the antimicrobial spectrum index, was compared with the antimicrobial index of Albert.     

In vitro and in vivo trypanocidal activity of the ethyl esters of N-allyl and N-propyl oxamates using different Trypanosoma cruzi strains

The trypanocidal activity of N-allyl (NAOx) and N-propyl (NPOx) oxamates and that of the ethyl esters ofN-allyl (Et-NAOx) and N-propyl (Et-NPOx) oxamates were tested on cultured epimastigotes (in vitro) and murine trypanosomiasis (in vivo) using five different T. cruzi strains. NAOx and NPOx did not penetrate intact epimastigotes and therefore we were not able to detect any trypanocidal effect with these oxamates. Whereas the ethyl esters (Et-NAOx and Et-NPOx), acting as prodrugs, exhibited in vitro and in vivo trypanocidal activity on the five tested T. cruzi strains. On the contrary, when Nifurtimox and Benznidazole used as reference drugs were tested, we found that only three of the five tested T cruzi strains were affected, whereas the other two strains, Miguz and Compostela, were resistant to the in vitro and in vivo trypanocidal activity of these compounds.     

Temperature-Sensitive Mutants of Vesicular Stomatitis Virus: In Vitro Studies of Virion-Associated Polymerase

The temperature dependence of the virion-associated polymerase activity of six temperature-sensitive (ts) mutants of vesicular stomatitis virus (tsW10, 11, 14, 16B, 28, and 29) has been examined in vitro and compared to the heat-resistant parent (HR). The polymerase of five of the mutants (tsW10, 11, 14, 16B, and 28) appears to be significantly more ts than that of HR. Because certain pairs of these five mutants can complement each other's in vitro polymerase activity, it appears that in vitro some components involved in the polymerase of one virion can be utilized by another virion. Examination of 19 revertants of tsW11 and tsW16B which had regained their ability to replicate at 38 C showed that their in vitro polymerase activity had also become less ts. Furthermore, it was found that the pairs of mutants which showed in vitro complementation of polymerase activity at 38 C were those which had shown complementation in yielding infectious progeny in mixedly infected cells. These two observations suggest that the ts behavior of the in vitro polymerase activity of the five mutants is related to their inability to replicate at the nonpermissive temperature.     

昆虫病原线虫共生菌BP品系杀虫毒素基因簇中各基因与杀虫活性的关系

昆虫病原线虫共生菌Xenorhabdus nematophilus BP的多个杀虫毒素基因集中在一起形成一个约40kb的基因簇。为研究这个基因簇中各基因与杀虫活性的关系,对该共生菌粘粒文库中5个粘粒克隆XnBP76、XnBP83、XnBP203、XnBPp378 和XnBP414及XnBP83的3个亚克隆插入DNA片段的基因结构和它们对棉铃虫的杀虫活性进行了比较,结果显示,xptB1, xptC1和xptA2 3个基因或后两者的联合表达产物具有最强的杀虫效果,缺失其中的任何1个或2个会使杀虫活力大幅度地下降或完全消失;而xptD1和xptA1的缺失对毒素基因簇的表达产物的杀虫活力影响很小;杀虫毒素的物理混合没有明显的增效作用。     

The activity of glutathione-S-transferases in various organs of the rat

The activity of glutathione-S-transferases for five electrophilic substrates was measured in ten organs of the rat. Highest activity was found in the liver and steroidogenic organs. The activity in the heart, brain, spleen and lung was relatively low or nil for most substrates.     

Daily activity and light exposure levels for five species of lemurs at the duke lemur center

Light is the primary synchronizer of all biological rhythms, yet little is known about the role of the 24‐hour luminous environment on nonhuman primate circadian patterns, making it difficult to understand the photic niche of the ancestral primate. Here we present the first data on proximate light–dark exposure and activity–rest patterns in free‐ranging nonhuman primates. Four individuals each of five species of lemurs at the Duke Lemur Center (Eulemur mongoz, Lemur catta, Propithecus coquereli, Varecia rubra, and Varecia variegata variegata) were fitted with a Daysimeter‐D pendant that contained light and accelerometer sensors. Our results reveal common as well as species‐specific light exposure and behavior patterns. As expected, all five species were more active between sunrise and sunset. All five species demonstrated an anticipatory increase in their pre‐sunrise activity that peaked at sunrise with all but V. rubra showing a reduction within an hour. All five species reduced activity during mid‐day. Four of the five stayed active after sunset, but P. coquereli began reducing their activity about 2 hours before sunset. Other subtle differences in the recorded light exposure and activity patterns suggest species‐specific photic niches and behaviors. The eventual application of the Daysimeter‐D in the wild may help to better understand the adaptive evolution of ancestral primates. Am J Phys Anthropol 153:68–77, 2014. © 2013 Wiley Periodicals, Inc.     

Immunological studies in pre-eclamptic toxaemia.

Although five patients with severe pre-eclamptic toxaemia (PET) had increased anticomplementary activity in their serum, there was no evidence of complement activation in the plasma of four of the five patients. These results are not implicated in the pathogenesis of PET. No significant correlation was found between anticomplementary activity and pregnancy-associated alpha2-glycoprotein.     

Studies of the "antihistaminic" effect of pyribenzamine administered by various routes

Utilizing histamine electrophoresis, the degree and duration of "antihistaminic" effect of varying doses of Pyribenzamine(R) administered by different routes were studied. Delayed action Pyribenzamine in 50 mg. and 100 mg. dosage exerted a small but measurable anti-whealing effect five hours after ingestion. The larger dose exerted approximately twice the effect of the smaller. The anti-whealing activity lasted five to six hours. Pyribenzamine given intravenously affected the whealing response one hour after administration. A peak of activity was reached two to two and a half hours after injection, and "antihistaminic" effect continued for a total of five hours. The inunction of 250 mg. and 500 mg. of Pyribenzamine in an ointment base resulted in sufficient absorption of the drug to produce a measurable anti-whealing effect. The "antihistaminic" activity was noted three hours after application and lasted 10 to 12 hours from the time of inunction.     

The influence of prey biomass on activity and consumption rates of brook trout

The objectives of this work were (1) to assess the influence of zooplankton biomass on activity and consumption rates of young-of-the-year brook trout ( Salvelinus fontinalis ) and (2) to validate an in situ enclosure approach to quantify energy allocation patterns in fish. These objectives were attained by directly estimating fish growth, consumption and activity rates on 10 occasions characterized by different levels of zooplankton biomass (0.005 to 0.100 mg dry weight 1⁻¹). One enclosure was used to estimate growth and activity rates and five additional enclosures were used to estimate consumption rates. Among-experiment variations of activity rates (sum for five trout = 2.4 to 33.5 calories day⁻¹) were proportionally more important than variations of consumption rates (sum for five trout = 59.5 to 112.7 calories day⁻¹). The results support the existence of a significant positive relationship between fish activity rates and zooplankton biomass. No significant relationship was found between consumption rates and prey biomass. Final size of fish inside the enclosure was within 7.6% of the value estimated using experimentally derived activity and consumption rates. This situation, together with the stability of among-enclosure activity and feeding schedules, suggested that the experimental design was appropriate to estimate fish energy allocation patterns. Combination of our observations with those of a previously published work indicated that small variations of fish size or zooplankton biomass can cause a two-fold variation of fish activity costs.     

Anti-inflammatory activity of 5 copper complexes

The anti-inflammatory activity of five copper complexes is shown in the cotton wad granuloma test in Rats. The activity due to copper seems to be only modulated by the ligands in the complexes studied.