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1.
Abstract

A new species of Paradasyhelea Macfie is described from females found on the Auckland Islands, New Zealand, and a key is presented to separate it from its five known congeners. New distribution and habitat records are presented for the three ceratopogonid species previously reported from the subantarctic islands of New Zealand—Forcipomyia kuscheli Sublette & Wirth, F. tapleyi Ingram & Macfie, and Dasyhelea aucklandensis Sublette & Wirth.  相似文献   

2.
Pupa, male and female adults of Dasyhelea (Prokempia) flava Carter, Ingram & Macfie, pupa and male adult of D. (Pseudoculicoides) acuta n. sp., and male adult of D. (Pseudoculicoides) comosa n. sp. are described and illustrated.  相似文献   

3.
SUMMARY: Streptococci and lactobacilli were isolated from the faeces and caecal contents of experimental pigs receiving various diets. Fifty-seven strains of streptococci and forty-one (representative of 220) lactobacilli were examined physiologically and serologically. Lactobacillus acidophilus and L. fermenti predominated among the lactobacilli, while the largest group of streptococci resembled the 'unclassified' strains of Barnes & Ingram (1955) and Barnes, Ingram & Ingram (1956) from bacon factory premises, pig faeces and canned hams.  相似文献   

4.
Glycinecin A is a narrow-spectrum bacteriocin that is produced by Xanthomonas campestris pv glycines 8ra, and which has potential as a control agent for Xanthomonas phytopathogens. Most of the glycinecin A produced by Xanthomonas campestris pv glycines 8ra was found in the culture medium, whereas the recombinant glycinecin A expressed in E. coli was located intracellularly (S. Heu, J. Oh, Y. Kang, S. Ryu, S.K. Cho, Y. Cho & M. Cho. 2001 Applied and Environmental Microbiololgy 67, 4105–4110). The plasmid pBL5, which contains a 6-kb DNA fragment that includes the glyA and glyB genes, secreted glycinecin A into the medium when expressed in E. coli. Serial deletions of pBL5 were performed, to clone the gene (glyC) that was involved in secreting the recombinant glycinecin A from E. coli. The glyC gene was located upstream of glyA and glyB, and encoded a protein of 51 amino acids. Complementation of the glyC mutation restored the secretion of recombinant glycinecin A in E. coli. The glyC gene appears to be critical for recombinant glycinecin A secretion, since deletion of glyC dramatically reduced glycinecin A secretion into the culture medium.  相似文献   

5.
High-intensity focused ultrasound (HIFU) is a rapidly developing, non-invasive technique for local treatment of solid tumors that produce coagulative tumor necrosis. This study is aimed to investigate the feasibility of proton magnetic resonance spectroscopy (MRS) on early assessing treatment of HIFU ablation in rabbit with VX2 liver tumor. HIFU ablation was performed on normal liver and VX2 tumor in rabbit, and MRS was performed on normal liver and VX2 tumor before and 2 days after 100% HIFU ablation or 80% ablation in tumor volume. Choline (Cho) and choline/lipid (Cho/Lip) ratios between complete and partial HIFU ablation of tumor were compared. Tissues were harvested and sequentially sliced to confirm the necrosis. In normal liver, the Cho value liver was not obviously changed after HIFU (P > .05), but the Cho/Lip ratio was decreased (P < .05). Cho in liver VX2 tumor was much higher than that in normal liver (P < .001). Cho and Cho/Lip ratio were significantly decreased in tumor after complete HIFU ablation and partial HIFU ablation, and the Cho value in complete HIFU tumor ablation did not show any difference from that in normal liver after HIFU (P > .05); however, the Cho value in partial ablation was still higher than that in normal liver before or in tumor after complete HIFU treatment due to the residual part of tumors, and Cho/Lip ratio is lower than that in complete HIFU treatment (P < .001). The changes in MRS parameters were consistent with histopathologic changes of the tumor tissues after treatment. MRS could differentiate the complete tumor necrosis from residual tumor tissue, when combined with magnetic resonance imaging. We conclude that MRS may be applied as an important, non-invasive biomarker for monitoring the thoroughness of HIFU ablation.  相似文献   

6.
MotivationA comprehensive characterization of the humoral response towards a specific antigen requires quantification of the B-cell receptor repertoire by next-generation sequencing (BCR-Seq), as well as the analysis of serum antibodies against this antigen, using proteomics. The proteomic analysis is challenging since it necessitates the mapping of antigen-specific peptides to individual B-cell clones.ResultsThe PASA web server provides a robust computational platform for the analysis and integration of data obtained from proteomics of serum antibodies. PASA maps peptides derived from antibodies raised against a specific antigen to corresponding antibody sequences. It then analyzes and integrates proteomics and BCR-Seq data, thus providing a comprehensive characterization of the humoral response. The PASA web server is freely available at https://pasa.tau.ac.il and open to all users without a login requirement.  相似文献   

7.
Synopsis A new histochemical method is described for the polychromatic staining and identification of phospholipids and sulpholipids in tissue sections. It is an adaptation of a chromatographic method described previously (Kennedy & Collier, 1962). Sections are stained in a mixture of Diamond Sky Blue B, Diamond Cyanine R and formalin, followed by differentiation in 2-morpholinoethanol and bromine water, counterstaining in Cresyl Fast Violet and decolorization in lactic acid.The interpretation of the final colours in the test tissues was checked by extraction and chromatography of their lipid content.The staining of diverse animal and plant tissues is described and illustrated in colour.  相似文献   

8.
α-Hemolysin (HlyA) is a protein toxin, a member of the pore-forming Repeat in Toxin (RTX) family, secreted by some pathogenic strands of Escherichia coli. The mechanism of action of this toxin seems to involve three stages that ultimately lead to cell lysis: binding, insertion, and oligomerization of the toxin within the membrane. Since the influence of phase segregation on HlyA binding and insertion in lipid membranes is not clearly understood, we explored at the meso- and nanoscale—both in situ and in real-time—the interaction of HlyA with lipid monolayers and bilayers. Our results demonstrate that HlyA could insert into monolayers of dioleoylphosphatidylcholine/sphingomyelin/cholesterol (DOPC/16:0SM/Cho) and DOPC/24:1SM/Cho. The time course for HlyA insertion was similar in both lipidic mixtures. HlyA insertion into DOPC/16:0SM/Cho monolayers, visualized by Brewster-angle microscopy (BAM), suggest an integration of the toxin into both the liquid-ordered and liquid-expanded phases. Atomic-force-microscopy imaging reported that phase boundaries favor the initial binding of the toxin, whereas after a longer time period the HlyA becomes localized into the liquid-disordered (Ld) phases of supported planar bilayers composed of DOPC/16:0SM/Cho. Our AFM images, however, showed that the HlyA interaction does not appear to match the general strategy described for other invasive proteins. We discuss these results in terms of the mechanism of action of HlyA.  相似文献   

9.
Abstract

A modified dichromatic iron-eriocyanine R (Fe-ECR) staining method is described. Staining obtained with this new technique generally was similar to that of hematoxylin and eosin (H & E). Cell nuclei were stained blue. Cardiac, smooth and skeletal muscle, and red blood cells, were stained different shades of red. Collagen fibers were stained different shades of orange, usually faintly. Decalcified bony tissue was stained pinkish violet. Epithelial cells were strongly stained deep shades of red, magenta and violet. Cartilage matrix, and goblet and mast cells were unstained. Although Fe-ECR staining differed too much from standard H & E staining to be a substitute for diagnostic purposes, the dichromatic method described might usefully replace van Gieson or trichrome stains, especially if muscle is of interest. A pH 0.95 staining solution was used to differentiate initially over-stained sections followed by washing in distilled water. This dichromatic technique is easier to perform and more precisely controllable than other ECR dichromatic methods. The entire procedure can be completed in less than 5 min. The technique has the advantages of greater technical simplicity and speed, a larger range of polychromasia, and a longer shelf-life than H & E. ECR also is more reliably available than hematoxylin and usually is less expensive.  相似文献   

10.
The B-cell Epitope Interaction Database (BEID; http://datam.i2r.a-star.edu.sg/BEID) is an open-access database describing sequence-structure-function information on immunoglobulin (Ig)-antigen interactions. The current version of the database contains 164 antigens, 126 Ig and 189 Ig-antigen complexes extracted from the Protein Data Bank (PDB). Each entry is manually verified, classified, and analyzed for intermolecular interactions between antigens and the corresponding bound Ig molecules. Ig-antigen interaction information that is stored in BEID includes solvent accessibility, hydrogen bonds, non-hydrogen bonds, gap volume, gap index, interface area and contact residues. The database can be searched with a user-friendly search tool and schematic diagrams for Ig-antigen interactions are available for download in PDF format. The ultimate purpose of BEID is to enhance the understanding of the rules of engagement between antigen and the corresponding bound Ig molecules. It is also a precious data source for developing computational predictors for B-cell epitopes.  相似文献   

11.
Despite the steadily decreasing costs of genome sequencing, prioritizing organisms for sequencing remains important in large-scale projects. Phylogeny-based selection is of interest to identify those organisms whose genomes can be expected to differ most from those that have already been sequenced. Here, we describe a method that infers a phylogenetic scoring independent of which set of organisms has previously been targeted, which is computationally simple and easy to apply in practice. The scoring itself, as well as pre- and post-processing of the data, is illustrated using two real-world examples in which the method has already been applied for selecting targets for genome sequencing. These projects are the JGI CSP Genomic Encyclopedia of Bacteria and Archaea phase I, targeting 1,000 type strains, and, on a smaller-scale, the phylogenomics of the Roseobacter clade. Potential artifacts of the method are discussed and compared to a selection approach based on the taxonomic classification.  相似文献   

12.
13.
Protein interaction in cells can be described at different levels. At a low interaction level, proteins function together in small, stable complexes and at a higher level, in sets of interacting complexes. All interaction levels are crucial for the living organism, and one of the challenges in proteomics is to measure the proteins at their different interaction levels. One common method for such measurements is immunoprecipitation followed by mass spectrometry (IP/MS), which has the potential to probe the different protein interaction forms. However, IP/MS data are complex because proteins, in their diverse interaction forms, manifest themselves in different ways in the data. Numerous bioinformatic tools for finding protein complexes in IP/MS data are currently available, but most tools do not provide information about the interaction level of the discovered complexes, and no tool is geared specifically to unraveling and visualizing these different levels. We present a new bioinformatic tool to explore IP/MS datasets for protein complexes at different interaction levels and show its performance on several real–life datasets. Our tool creates clusters that represent protein complexes, but unlike previous methods, it arranges them in a tree–shaped structure, reporting why specific proteins are predicted to build a complex and where it can be divided into smaller complexes. In every data analysis method, parameters have to be chosen. Our method can suggest values for its parameters and comes with adapted visualization tools that display the effect of the parameters on the result. The tools provide fast graphical feedback and allow the user to interact with the data by changing the parameters and examining the result. The tools also allow for exploring the different organizational levels of the protein complexes in a given dataset. Our method is available as GNU-R source code and includes examples at www.bdagroup.nl.  相似文献   

14.
Jacques Médus 《Grana》2013,52(2):149-158
A method for the stratigraphical correlation and dating of Lower Cretaceous deposits from south-eastern France and north-eastern Spain is proposed, on the basis of a morphological analysis of pollen grains belonging to the form-genus Classopollis (Pflug) Pocock & Jansonius. This method has made possible correlations between microfloristic assemblages from various regions and it solves the problem of the age of the Wealden and Utrillas facies in the region studied. The correlation between these facies and the levels associated with bauxite suggests that a biostratigraphical interpretation would be possible by further application of the method described.  相似文献   

15.
16.
Three-dimensional (3D) culture models are critical tools for understanding tissue morphogenesis. A key requirement for their analysis is the ability to reconstruct the tissue into computational models that allow quantitative evaluation of the formed structures. Here, we present Software for Automated Morphological Analysis (SAMA), a method by which epithelial structures grown in 3D cultures can be imaged, reconstructed and analyzed with minimum human intervention. SAMA allows quantitative analysis of key features of epithelial morphogenesis such as ductal elongation, branching and lumen formation that distinguish different hormonal treatments. SAMA is a user-friendly set of customized macros operated via FIJI (http://fiji.sc/Fiji), an open-source image analysis platform in combination with a set of functions in R (http://www.r-project.org/), an open-source program for statistical analysis. SAMA enables a rapid, exhaustive and quantitative 3D analysis of the shape of a population of structures in a 3D image. SAMA is cross-platform, licensed under the GPLv3 and available at http://montevil.theobio.org/content/sama.  相似文献   

17.
18.
Neisseria meningitidis is a major cause of septicaemia and meningitis worldwide. Most disease in Europe, the Americas and Australasia is caused by meningococci expressing serogroup B capsules, but no vaccine against this polysaccharide exists. Potential candidates for ‘serogroup B substitute’ vaccines are outer membrane protein antigens including the typing antigens PorA and FetA. The web-accessible PubMLST database (www.pubmlst.org) was used to investigate the temporal and geographical patterns of associations among PorA and FetA protein variants and lineages defined by combinations of housekeeping genes, known as clonal complexes. The sample contained 3460 isolates with genotypic information from 57 countries over a 74 year period. Although shifting associations among antigen variants and clonal complexes were evident, a subset of strain types associated with several serogroups persisted for decades and proliferated globally. Genetic stability among outer membrane proteins of serogroup A meningococci has been described previously, but here long-lived genetic associations were also observed among meningococci belonging to serogroups B and C. The patterns of variation were consistent with behaviour predicted by models that invoke inter-strain competition mediated by immune selection. There was also substantial geographic and temporal heterogeneity in antigenic repertoires, providing both opportunities and challenges for the design of broad coverage protein-based meningococcal vaccines.  相似文献   

19.
Sliding Box Docking is a program that manages simulations of ligand docking at different defined positions of a three-dimensional DNA structure. The procedure is similar to inverse docking, which is a method that performs docking simulations of a single ligand in the active sites of different targets. Sliding Box Docking manages docking simulations of one ligand into a box that slides along the DNA helix axis in regular steps. For each box position a score is calculated using the separate Autodock Vina software, and the results are automatically plotted. The evaluation of ligand interaction at different DNA locations can highlight the specificity of ligands for different DNA- sequences. When assessing the affinity between ligans AT base pairs, results for docking simulations with a test set that included berenil, distamycin, hoechst 33258, and netropsin were as expected, agreeing well with affinities previously described in the literature.

Availability

Binaries are freely available at https://sourceforge.net/projects/slidingboxdocki  相似文献   

20.
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