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51.
Bacillus pumilus was isolated from surface-sterilized tissues of the medicinal plant Ocimum sanctum. Scanning electron microscopic (SEM) imaging confirmed the presence of a rod shaped bacterium within the plant tissues. The bacterium was identified as B. pumilus by biochemical analyses and 16S rRNA gene sequencing. In vitro analyses indicate that the isolated strain of B. pumilus was endowed with multiple plant growth promotion (PGP) traits such as phosphate solubilization and the production of indole acetic acid (IAA), siderophore and hydrogen cyanide (HCN). Phosphate solubilization (37.3 μg ml?1) and IAA production (36.7 μg ml?1) by the isolate was found to reach a maximum after 60 h of incubation. Siderophore mediated iron sequestration by B. pumilus may confer a competitive advantage to the host with respect to pathogen inhibition. Siderophore produced by the isolate was found to be of a trihydroxamate type with hexadentate nature. The B. pumilus isolate also exhibited cellulolytic, proteolytic and chitinolytic activity. Cell free supernatant, culture filtrates of the isolate were found to suppress the growth of fungal phytopathogens. The culture filtrate retained its antifungal activity even after exposure to heat. In addition to PGP, the isolate exhibited probiotic properties such as acid tolerance (pH2), bile salt tolerance (2 %), auto-aggregation, antibiotic resistance and the absence of haemolytic activity. These finding suggest the possibility of utilizing this endophytic strain of B. pumilus as a bioinoculant to enhance plant growth and also as a probiotic. 相似文献
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RM Christie 《Biotechnic & histochemistry》2013,88(2):51-56
Although the color of indigo is strongly dependent on its environment, it is blue in most commonly encountered situations. Indigo's absorption at such long wavelengths for such a small molecule is unique, and I provide here an overview of the concepts advanced to account for this feature. A traditional valence–bond approach may be used to provide a reasonable qualitative explanation. A more rigorous, quantitative explanation is provided by molecular orbital methods of varying degrees of sophistication and several explanations have been proposed based on these models. Commonly, it is suggested that the important structural unit in determining color is based on the cross-conjugated “H-chromophore” concept. A second closely related explanation describes it as two symmetrically coupled merocyanine chains. Another proposal suggests that the basic chromophore may be interpreted as the aza analogue of two coupled anti aromatic-cyclopentadienyl ions. PiSYSTEM, a commercially available quantum mechanics program, has been used to provide a successful quantitative account of the colors of indigo and indirubin, a red isomer. 相似文献
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da Silva FH Pereira VG Yasumura EG Tenório LZ de Carvalho LP Lisboa BC Matsumoto PK Stilhano RS Samoto VY Calegare BF Brandão Lde C D'Almeida V Filippo TR Porcionatto M Toma L Nader HB Valero VB Camassola M Nardi NB Han SW 《Genetic vaccines and therapy》2012,10(1):2-11
Background
Mucopolysaccharidosis type I (MPSI) is caused by a deficiency in alpha-L iduronidase (IDUA), which leads to lysosomal accumulation of the glycosaminoglycans (GAGs) dermatan and heparan sulfate. While the currently available therapies have good systemic effects, they only minimally affect the neurodegenerative process. Based on the neuroprotective and tissue regenerative properties of mesenchymal stem cells (MSCs), we hypothesized that the administration of MSCs transduced with a murine leukemia virus (MLV) vector expressing IDUA to IDUA KO mouse brains could reduce GAG deposition in the brain and, as a result, improve neurofunctionality, as measured by exploratory activity.Methods
MSCs infected with an MLV vector encoding IDUA were injected into the left ventricle of the brain of 12- or 25-month-old IDUA KO mice. The behavior of the treated mice in the elevated plus maze and open field tests was observed for 1 to 2 months. Following these observations, the brains were removed for biochemical and histological analyses.Results
After 1 or 2 months of observation, the presence of the transgene in the brain tissue of almost all of the treated mice was confirmed using PCR, and a significant reduction in GAG deposition was observed. This reduction was directly reflected in an improvement in exploratory activity in the open field and the elevated plus maze tests. Despite these behavioral improvements and the reduction in GAG deposition, IDUA activity was undetectable in these samples. Overall, these results indicate that while the initial level of IDUA was not sustainable for a month, it was enough to reduce and maintain low GAG deposition and improve the exploratory activity for months.Conclusions
These data show that gene therapy, via the direct injection of IDUA-expressing MSCs into the brain, is an effective way to treat neurodegeneration in MPSI mice. 相似文献56.
Sara D'Angelo Jacob Glanville Fortunato Ferrara Leslie Naranjo Cheryl D Gleasner Xiaohong Shen Andrew RM Bradbury Csaba Kiss 《MABS-AUSTIN》2014,6(1):160-172
In vitro selection has been an essential tool in the development of recombinant antibodies against various antigen targets. Deep sequencing has recently been gaining ground as an alternative and valuable method to analyze such antibody selections. The analysis provides a novel and extremely detailed view of selected antibody populations, and allows the identification of specific antibodies using only sequencing data, potentially eliminating the need for expensive and laborious low-throughput screening methods such as enzyme-linked immunosorbant assay. The high cost and the need for bioinformatics experts and powerful computer clusters, however, have limited the general use of deep sequencing in antibody selections. Here, we describe the AbMining ToolBox, an open source software package for the straightforward analysis of antibody libraries sequenced by the three main next generation sequencing platforms (454, Ion Torrent, MiSeq). The ToolBox is able to identify heavy chain CDR3s as effectively as more computationally intense software, and can be easily adapted to analyze other portions of antibody variable genes, as well as the selection outputs of libraries based on different scaffolds. The software runs on all common operating systems (Microsoft Windows, Mac OS X, Linux), on standard personal computers, and sequence analysis of 1–2 million reads can be accomplished in 10–15 min, a fraction of the time of competing software. Use of the ToolBox will allow the average researcher to incorporate deep sequence analysis into routine selections from antibody display libraries. 相似文献
57.
Winter activity patterns of 16 radio-marked capercaillie, Tetrao urogallus , were studied during 1981–83 at Varaldskogen, SE Norway. Activity was confined to the light hours of the day, closely following the photoperiod. Diel distribution showed a major peak near sunset during every month. A second peak was found in the morning. This peak was comparable to the evening peak in early and late winter, but nearly disappeared in midwinter. Ambient temperature rather than photoperiod seemed to be the important proximate factor responsible for the changes in morning activity. By postponing activity to the afternoon, capercaillie avoids energy expenditure during the coldest morning hours.
Total daily activity (TDA) during the period November-April averaged about 3 h for both sexes. TDA of cocks was U-shaped with the lowest values (2.0 h) in December-January, whereas TDA of hens was fairly stable during November-March with mean value of 2.7 h, increasing abruptly to 4 h in April. TDA during December-January is believed to express the time used for feeding in pine trees. The significantly higher TDA of hens (26%) compared with cocks during this period may be explained by a higher relative heat loss of hens (body weights: hens 2.0 kg, cocks 4.3 kg). The increased level of activity during early and late winter among cocks was probably due to display and related territorial behaviour, whereas increased activity of hens during April probably was caused by a shift from feeding in pines to more time-consuming, selective feeding on the ground 相似文献
Total daily activity (TDA) during the period November-April averaged about 3 h for both sexes. TDA of cocks was U-shaped with the lowest values (2.0 h) in December-January, whereas TDA of hens was fairly stable during November-March with mean value of 2.7 h, increasing abruptly to 4 h in April. TDA during December-January is believed to express the time used for feeding in pine trees. The significantly higher TDA of hens (26%) compared with cocks during this period may be explained by a higher relative heat loss of hens (body weights: hens 2.0 kg, cocks 4.3 kg). The increased level of activity during early and late winter among cocks was probably due to display and related territorial behaviour, whereas increased activity of hens during April probably was caused by a shift from feeding in pines to more time-consuming, selective feeding on the ground 相似文献
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Effects of deposition of deer dung on nutrient redistribution and on soil and plant nutrients on intensively grazed grasslands in lowland Nepal 总被引:1,自引:0,他引:1
Nutrient redistribution, deer response to areas containing dung, and plant and soil nutrient content on grazing lawns and
adjacent control areas were studied on intensively grazed grasslands in humid lowland Nepal. Effects of experimental fertilisation
of grasslands with different amounts of dung pellets were also studied. A high-density population of axis deer recirculated
13 tons (dry mass, DM) of dung per month in the 10 km2 study area. Because of preferential use of the grasslands for feeding while resting elsewhere, 10 tons were lost from the
grassland to other habitat types per month during the dry season (February–May). The N, P, K, Na, and Mg content of grass
from grazing lawns was significantly higher, probably because the grass was kept in a younger phenological stage of growth.
In contrast with results from many other studies, the nutrient content of lawn soil was similar to that of adjacent, less
intensively grazed areas, apart from P, which was lower in lawn soils. High plant P requirement on grazing lawns and removal
of nutrients by deer may explain low soil P levels. Experiments with pellet fertilisation showed that high dung deposition
increased plant P content, probably because of increased P uptake during early stages of growth. Dung deposition did not affect
deer grazing preferences. 相似文献
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Gündisch D Harms K Schwarz S Seitz G Stubbs MT Wegge T 《Bioorganic & medicinal chemistry》2001,9(10):2683-2691
In this structure-affinity relationship (SAFIR) study, the bioisosteric potential of diazines in the field of ferruginine-type nAChR ligands was investigated. Novel enantiopure analogues of (-)-Ferruginine (3) such as 6-8 were synthesized utilizing enantiomerically pure N-protected (+)-2-tropanone 9 from the 'chiral pool' as versatile chiral building block and a palladium-catalyzed Stille cross-coupling of the tributylstannyl diazines 12, 14 and 16 with the vinyl triflate 11 of (+)-2-tropanone 9. The structures of the novel diazine analogues 6-8 of (-)-ferruginine (3) were assigned on the basis of spectral data, that of ligand 7 being additionally verified by X-ray crystallography. The bioisosteric replacement of the acetyl moiety as structural part of the lead compound 3 with the pyridazine, pyrimidine and pyrazine nucleus resulted in ligands with high to moderate affinity for the central alpha4beta2 and remarkably low affinity for the alpha7* nAChR subtypes. Among the compounds synthesized and tested, 7 was the most active one with K(i)=3.7 nM (alpha4beta2). Compared with the lead 3, this value represents a 30-fold improvement in the affinity for the alpha4beta2 subtype combined with a substantially improved selectivity ratio between the alpha4beta2 and alpha7* subtypes. 相似文献
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Fortunato Ferrara Sara D’Angelo Tiziano Gaiotto Leslie Naranjo Hongzhao Tian Susanne Gr?slund Elena Dobrovetsky Peter Hraber Fridtjof Lund-Johansen Silvia Saragozza Daniele Sblattero Csaba Kiss Andrew RM Bradbury 《MABS-AUSTIN》2015,7(1):32-41
Only a small fraction of the antibodies in a traditional polyclonal antibody mixture recognize the target of interest, frequently resulting in undesirable polyreactivity. Here, we show that high-quality recombinant polyclonals, in which hundreds of different antibodies are all directed toward a target of interest, can be easily generated in vitro by combining phage and yeast display. We show that, unlike traditional polyclonals, which are limited resources, recombinant polyclonal antibodies can be amplified over one hundred million-fold without losing representation or functionality. Our protocol was tested on 9 different targets to demonstrate how the strategy allows the selective amplification of antibodies directed toward desirable target specific epitopes, such as those found in one protein but not a closely related one, and the elimination of antibodies recognizing common epitopes, without significant loss of diversity. These recombinant renewable polyclonal antibodies are usable in different assays, and can be generated in high throughput. This approach could potentially be used to develop highly specific recombinant renewable antibodies against all human gene products. 相似文献