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Sample records for mycoplasma mobile gliding

  1. Gliding Direction of Mycoplasma mobile

    PubMed Central

    Morio, Hanako; Kasai, Taishi

    2015-01-01

    ABSTRACT Mycoplasma mobile glides in the direction of its cell pole by a unique mechanism in which hundreds of legs, each protruding from its own gliding unit, catch, pull, and release sialylated oligosaccharides fixed on a solid surface. In this study, we found that 77% of cells glided to the left with a change in direction of 8.4° ± 17.6° μm−1 displacement. The cell body did not roll around the cell axis, and elongated, thinner cells also glided while tracing a curved trajectory to the left. Under viscous conditions, the range of deviation of the gliding direction decreased. In the presence of 250 μM free sialyllactose, in which the binding of the legs (i.e., the catching of sialylated oligosaccharides) was reduced, 70% and 30% of cells glided to the left and the right, respectively, with changes in direction of ∼30° μm−1. The gliding ghosts, in which a cell was permeabilized by Triton X-100 and reactivated by ATP, glided more straightly. These results can be explained by the following assumptions based on the suggested gliding machinery and mechanism: (i) the units of gliding machinery may be aligned helically around the cell, (ii) the legs extend via the process of thermal fluctuation and catch the sialylated oligosaccharides, and (iii) the legs generate a propulsion force that is tilted from the cell axis to the left in 70% and to the right in 30% of cells. IMPORTANCE Mycoplasmas are bacteria that are generally parasitic to animals and plants. Some Mycoplasma species form a protrusion at a pole, bind to solid surfaces, and glide. Although these species appear to consistently glide in the direction of the protrusion, their exact gliding direction has not been examined. This study analyzed the gliding direction in detail under various conditions and, based on the results, suggested features of the machinery and the mechanism of gliding. PMID:26503848

  2. Gliding Motility of Mycoplasma mobile on Uniform Oligosaccharides

    PubMed Central

    Kasai, Taishi; Hamaguchi, Tasuku

    2015-01-01

    ABSTRACT The binding and gliding of Mycoplasma mobile on a plastic plate covered by 53 uniform oligosaccharides were analyzed. Mycoplasmas bound to and glided on only 21 of the fixed sialylated oligosaccharides (SOs), showing that sialic acid is essential as the binding target. The affinities were mostly consistent with our previous results on the inhibitory effects of free SOs and suggested that M. mobile recognizes SOs from the nonreducing end with four continuous sites as follows. (i and ii) A sialic acid at the nonreducing end is tightly recognized by tandemly connected two sites. (iii) The third site is recognized by a loose groove that may be affected by branches. (iv) The fourth site is recognized by a large groove that may be enhanced by branches, especially those with a negative charge. The cells glided on uniform SOs in manners apparently similar to those of the gliding on mixed SOs. The gliding speed was related inversely to the mycoplasma's affinity for SO, suggesting that the detaching step may be one of the speed determinants. The cells glided faster and with smaller fluctuations on the uniform SOs than on the mixtures, suggesting that the drag caused by the variation in SOs influences gliding behaviors. IMPORTANCE Mycoplasma is a group of bacteria generally parasitic to animals and plants. Some Mycoplasma species form a protrusion at a pole, bind to solid surfaces, and glide in the direction of the protrusion. These procedures are essential for parasitism. Usually, mycoplasmas glide on mixed sialylated oligosaccharides (SOs) derived from glycoprotein and glycolipid. Since gliding motility on uniform oligosaccharides has never been observed, this study gives critical information about recognition and interaction between receptors and SOs. PMID:26148712

  3. Prospects for the gliding mechanism of Mycoplasma mobile.

    PubMed

    Miyata, Makoto; Hamaguchi, Tasuku

    2016-02-01

    Mycoplasma mobile forms gliding machinery at a cell pole and glides continuously in the direction of the cell pole at up to 4.5μm per second on solid surfaces such as animal cells. This motility system is not related to those of any other bacteria or eukaryotes. M. mobile uses ATP energy to repeatedly catch, pull, and release sialylated oligosaccharides on host cells with its approximately 50-nm long legs. The gliding machinery is a large structure composed of huge surface proteins and internal jellyfish-like structure. This system may have developed from an accidental combination between an adhesin and a rotary ATPase, both of which are essential for the adhesive parasitic life of Mycoplasmas. PMID:26500189

  4. Unitary step of gliding machinery in Mycoplasma mobile

    PubMed Central

    Kinosita, Yoshiaki; Nakane, Daisuke; Sugawa, Mitsuhiro; Masaike, Tomoko; Mizutani, Kana; Miyata, Makoto; Nishizaka, Takayuki

    2014-01-01

    Among the bacteria that glide on substrate surfaces, Mycoplasma mobile is one of the fastest, exhibiting smooth movement with a speed of 2.0–4.5 μm⋅s−1 with a cycle of attachment to and detachment from sialylated oligosaccharides. To study the gliding mechanism at the molecular level, we applied an assay with a fluorescently labeled and membrane-permeabilized ghost model, and investigated the motility by high precision colocalization microscopy. Under conditions designed to reduce the number of motor interactions on a randomly oriented substrate, ghosts took unitary 70-nm steps in the direction of gliding. Although it remains possible that the stepping behavior is produced by multiple interactions, our data suggest that these steps are produced by a unitary gliding machine that need not move between sites arranged on a cytoskeletal lattice. PMID:24912194

  5. Directed Binding of Gliding Bacterium, Mycoplasma mobile, Shown by Detachment Force and Bond Lifetime

    PubMed Central

    Tanaka, Akihiro; Nakane, Daisuke; Mizutani, Masaki; Nishizaka, Takayuki

    2016-01-01

    ABSTRACT Mycoplasma mobile, a fish-pathogenic bacterium, features a protrusion that enables it to glide smoothly on solid surfaces at a velocity of up to 4.5 µm s−1 in the direction of the protrusion. M. mobile glides by a repeated catch-pull-release of sialylated oligosaccharides fixed on a solid surface by hundreds of 50-nm flexible “legs” sticking out from the protrusion. This gliding mechanism may be explained by a possible directed binding of each leg with sialylated oligosaccharides, by which the leg can be detached more easily forward than backward. In the present study, we used a polystyrene bead held by optical tweezers to detach a starved cell at rest from a glass surface coated with sialylated oligosaccharides and concluded that the detachment force forward is 1.6- to 1.8-fold less than that backward, which may be linked to a catch bond-like behavior of the cell. These results suggest that this directed binding has a critical role in the gliding mechanism. PMID:27353751

  6. Localization of P42 and F1-ATPase α-Subunit Homolog of the Gliding Machinery in Mycoplasma mobile Revealed by Newly Developed Gene Manipulation and Fluorescent Protein Tagging

    PubMed Central

    Tulum, Isil; Yabe, Masaru; Uenoyama, Atsuko

    2014-01-01

    Mycoplasma mobile has a unique mechanism that enables it to glide on solid surfaces faster than any other gliding mycoplasma. To elucidate the gliding mechanism, we developed a transformation system for M. mobile based on a transposon derived from Tn4001. Modification of the electroporation conditions, outgrowth time, and colony formation from the standard method for Mycoplasma species enabled successful transformation. A fluorescent-protein tagging technique was developed using the enhanced yellow fluorescent protein (EYFP) and applied to two proteins that have been suggested to be involved in the gliding mechanism: P42 (MMOB1050), which is transcribed as continuous mRNA with other proteins essential for gliding, and a homolog of the F1-ATPase α-subunit (MMOB1660). Analysis of the amino acid sequence of P42 by PSI-BLAST suggested that P42 evolved from a common ancestor with FtsZ, the bacterial tubulin homologue. The roles of P42 and the F1-ATPase subunit homolog are discussed as part of our proposed gliding mechanism. PMID:24509320

  7. Reprint of “Prospects for the gliding mechanism of Mycoplasma mobile”.

    PubMed

    Miyata, Makoto; Hamaguchi, Tasuku

    2015-12-01

    Mycoplasma mobile forms gliding machinery at a cell pole and glides continuously in the direction of the cell pole at up to 4.5 μm per second on solid surfaces such as animal cells. This motility system is not related to those of any other bacteria or eukaryotes. M. mobile uses ATP energy to repeatedly catch, pull, and release sialylated oligosaccharides on host cells with its approximately 50-nm long legs. The gliding machinery is a large structure composed of huge surface proteins and internal jellyfish-like structure. This system may have developed from an accidental combination between an adhesin and a rotary ATPase, both of which are essential for the adhesive parasitic life of Mycoplasmas. PMID:26711226

  8. The complete genome and proteome of Mycoplasma mobile.

    PubMed

    Jaffe, Jacob D; Stange-Thomann, Nicole; Smith, Cherylyn; DeCaprio, David; Fisher, Sheila; Butler, Jonathan; Calvo, Sarah; Elkins, Tim; FitzGerald, Michael G; Hafez, Nabil; Kodira, Chinnappa D; Major, John; Wang, Shunguang; Wilkinson, Jane; Nicol, Robert; Nusbaum, Chad; Birren, Bruce; Berg, Howard C; Church, George M

    2004-08-01

    Although often considered "minimal" organisms, mycoplasmas show a wide range of diversity with respect to host environment, phenotypic traits, and pathogenicity. Here we report the complete genomic sequence and proteogenomic map for the piscine mycoplasma Mycoplasma mobile, noted for its robust gliding motility. For the first time, proteomic data are used in the primary annotation of a new genome, providing validation of expression for many of the predicted proteins. Several novel features were discovered including a long repeating unit of DNA of approximately 2435 bp present in five complete copies that are shown to code for nearly identical yet uniquely expressed proteins. M. mobile has among the lowest DNA GC contents (24.9%) and most reduced set of tRNAs of any organism yet reported (28). Numerous instances of tandem duplication as well as lateral gene transfer are evident in the genome. The multiple available complete genome sequences for other motile and immotile mycoplasmas enabled us to use comparative genomic and phylogenetic methods to suggest several candidate genes that might be involved in motility. The results of these analyses leave open the possibility that gliding motility might have arisen independently more than once in the mycoplasma lineage. PMID:15289470

  9. Integrated Information and Prospects for Gliding Mechanism of the Pathogenic Bacterium Mycoplasma pneumoniae

    PubMed Central

    Miyata, Makoto; Hamaguchi, Tasuku

    2016-01-01

    Mycoplasma pneumoniae forms a membrane protrusion at a cell pole and is known to adhere to solid surfaces, including animal cells, and can glide on these surfaces with a speed up to 1 μm per second. Notably, gliding appears to be involved in the infectious process in addition to providing the bacteria with a means of escaping the host's immune systems. However, the genome of M. pneumoniae does not encode any of the known genes found in other bacterial motility systems or any conventional motor proteins that are responsible for eukaryotic motility. Thus, further analysis of the mechanism underlying M. pneumoniae gliding is warranted. The gliding machinery formed as the membrane protrusion can be divided into the surface and internal structures. On the surface, P1 adhesin, a 170 kDa transmembrane protein forms an adhesin complex with other two proteins. The internal structure features a terminal button, paired plates, and a bowl (wheel) complex. In total, the organelle is composed of more than 15 proteins. By integrating the currently available information by genetics, microscopy, and structural analyses, we have suggested a working model for the architecture of the organelle. Furthermore, in this article, we suggest and discuss a possible mechanism of gliding based on the structural model, in which the force generated around the bowl complex transmits through the paired plates, reaching the adhesin complex, resulting in the repeated catch of sialylated oligosaccharides on the host surface by the adhesin complex. PMID:27446003

  10. Periodicity in Attachment Organelle Revealed by Electron Cryotomography Suggests Conformational Changes in Gliding Mechanism of Mycoplasma pneumoniae

    PubMed Central

    Kawamoto, Akihiro; Matsuo, Lisa; Kato, Takayuki; Yamamoto, Hiroki

    2016-01-01

    ABSTRACT Mycoplasma pneumoniae, a pathogenic bacterium, glides on host surfaces using a unique mechanism. It forms an attachment organelle at a cell pole as a protrusion comprised of knoblike surface structures and an internal core. Here, we analyzed the three-dimensional structure of the organelle in detail by electron cryotomography. On the surface, knoblike particles formed a two-dimensional array, albeit with limited regularity. Analyses using a nonbinding mutant and an antibody showed that the knoblike particles correspond to a naplike structure that has been observed by negative-staining electron microscopy and is likely to be formed as a complex of P1 adhesin, the key protein for binding and gliding. The paired thin and thick plates feature a rigid hexagonal lattice and striations with highly variable repeat distances, respectively. The combination of variable and invariant structures in the internal core and the P1 adhesin array on the surface suggest a model in which axial extension and compression of the thick plate along a rigid thin plate is coupled with attachment to and detachment from the substrate during gliding. PMID:27073090

  11. Molecular shape and binding force of Mycoplasma mobile's leg protein Gli349 revealed by an AFM study

    SciTech Connect

    Lesoil, Charles; Nonaka, Takahiro; Sekiguchi, Hiroshi; Osada, Toshiya; Miyata, Makoto; Afrin, Rehana; Ikai, Atsushi

    2010-01-15

    Recent studies of the gliding bacteria Mycoplasma mobile have identified a family of proteins called the Gli family which was considered to be involved in this novel and yet fairly unknown motility system. The 349 kDa protein called Gli349 was successfully isolated and purified from the bacteria, and electron microscopy imaging and antibody experiments led to the hypothesis that it acts as the 'leg' of M. mobile, responsible for attachment to the substrate as well as for gliding motility. However, more precise evidence of the molecular shape and function of this protein was required to asses this theory any further. In this study, an atomic force microscope (AFM) was used both as an imaging and a force measurement device to provide new information about Gli349 and its role in gliding motility. AFM images of the protein were obtained revealing a complex structure with both rigid and flexible parts, consistent with previous electron micrographs of the protein. Single-molecular force spectroscopy experiments were also performed, revealing that Gli349 is able to specifically bind to sialyllactose molecules and withstand unbinding forces around 70 pN. These findings strongly support the idea that Gli349 is the 'leg' protein of M. mobile, responsible for binding and also most probably force generation during gliding motility.

  12. Decoding system for the AUA codon by tRNAIle with the UAU anticodon in Mycoplasma mobile

    PubMed Central

    Taniguchi, Takaaki; Miyauchi, Kenjyo; Nakane, Daisuke; Miyata, Makoto; Muto, Akira; Nishimura, Susumu; Suzuki, Tsutomu

    2013-01-01

    Deciphering the genetic code is a fundamental process in all living organisms. In many bacteria, AUA codons are deciphered by tRNAIle2 bearing lysidine (L) at the wobble position. L is a modified cytidine introduced post-transcriptionally by tRNAIle-lysidine synthetase (TilS). Some bacteria, including Mycoplasma mobile, do not carry the tilS gene, indicating that they have established a different system to decode AUA codons. In this study, tRNAIle2 has been isolated from M. mobile and was found to contain a UAU anticodon without any modification. Mycoplasma mobile isoleucyl-tRNA synthetase (IleRS) recognized the UAU anticodon, whereas Escherichia coli IleRS did not efficiently aminoacylate tRNAIle2UAU. In M. mobile IleRS, a single Arg residue at position 865 was critical for specificity for the UAU anticodon and, when the corresponding site (W905) in E. coli IleRS was substituted with Arg, the W905R mutant efficiently aminoacylated tRNA with UAU anticodon. Mycoplasma mobile tRNAIle2 cannot distinguish between AUA and AUG codon on E. coli ribosome. However, on M. mobile ribosome, M. mobile tRNAIle2UAU specifically recognized AUA codon, and not AUG codon, suggesting M. mobile ribosome has a property that prevents misreading of AUG codon. These findings provide an insight into the evolutionary reorganization of the AUA decoding system. PMID:23295668

  13. [Mechanism of bacterial gliding motility].

    PubMed

    Nakane, Daisuke

    2015-01-01

    Bacteria have various way to move over solid surfaces, such as glass, agar, and host cell. These movements involve surface appendages including flagella, type IV pili and other "mysterious" nano-machineries. Gliding motility was a term used various surface movements by several mechanisms that have not been well understood in past few decades. However, development of visualization techniques allowed us to make much progress on their dynamics of machineries. It also provided us better understanding how bacteria move over surfaces and why bacteria move in natural environments. In this review, I will introduce recent studies on the gliding motility of Flavobacteium and Mycoplasma based on the detail observation of single cell and its motility machinery with micro-nano scales. PMID:26632217

  14. Performance analysis of jump-gliding locomotion for miniature robotics.

    PubMed

    Vidyasagar, A; Zufferey, Jean-Christohphe; Floreano, Dario; Kovač, M

    2015-04-01

    Recent work suggests that jumping locomotion in combination with a gliding phase can be used as an effective mobility principle in robotics. Compared to pure jumping without a gliding phase, the potential benefits of hybrid jump-gliding locomotion includes the ability to extend the distance travelled and reduce the potentially damaging impact forces upon landing. This publication evaluates the performance of jump-gliding locomotion and provides models for the analysis of the relevant dynamics of flight. It also defines a jump-gliding envelope that encompasses the range that can be achieved with jump-gliding robots and that can be used to evaluate the performance and improvement potential of jump-gliding robots. We present first a planar dynamic model and then a simplified closed form model, which allow for quantification of the distance travelled and the impact energy on landing. In order to validate the prediction of these models, we validate the model with experiments using a novel jump-gliding robot, named the 'EPFL jump-glider'. It has a mass of 16.5 g and is able to perform jumps from elevated positions, perform steered gliding flight, land safely and traverse on the ground by repetitive jumping. The experiments indicate that the developed jump-gliding model fits very well with the measured flight data using the EPFL jump-glider, confirming the benefits of jump-gliding locomotion to mobile robotics. The jump-glide envelope considerations indicate that the EPFL jump-glider, when traversing from a 2 m height, reaches 74.3% of optimal jump-gliding distance compared to pure jumping without a gliding phase which only reaches 33.4% of the optimal jump-gliding distance. Methods of further improving flight performance based on the models and inspiration from biological systems are presented providing mechanical design pathways to future jump-gliding robot designs. PMID:25811417

  15. Mycoplasma pneumonia

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/000082.htm Mycoplasma pneumonia To use the sharing features on this page, please enable JavaScript. Mycoplasma pneumonia is an infection of the lungs by the ...

  16. Novel mechanisms power bacterial gliding motility.

    PubMed

    Nan, Beiyan; Zusman, David R

    2016-07-01

    For many bacteria, motility is essential for survival, growth, virulence, biofilm formation and intra/interspecies interactions. Since natural environments differ, bacteria have evolved remarkable motility systems to adapt, including swimming in aqueous media, and swarming, twitching and gliding on solid and semi-solid surfaces. Although tremendous advances have been achieved in understanding swimming and swarming motilities powered by flagella, and twitching motility powered by Type IV pili, little is known about gliding motility. Bacterial gliders are a heterogeneous group containing diverse bacteria that utilize surface motilities that do not depend on traditional flagella or pili, but are powered by mechanisms that are less well understood. Recently, advances in our understanding of the molecular machineries for several gliding bacteria revealed the roles of modified ion channels, secretion systems and unique machinery for surface movements. These novel mechanisms provide rich source materials for studying the function and evolution of complex microbial nanomachines. In this review, we summarize recent findings made on the gliding mechanisms of the myxobacteria, flavobacteria and mycoplasmas. PMID:27028358

  17. Genital mycoplasmas.

    PubMed

    Hartmann, Martin

    2009-04-01

    The first described pathogenic organisms that caused urethritis were Neisseria gonorrhoeae and Chlamydia trachomatis. The significance of detecting mycoplasma with genital swabs remained unclear for a long time. Culture can differentiate between Ureaplasma urealyticum and Mycoplasma hominis. After introduction of nuclear acid amplification, Mycoplasma genitalium was additionally detected, while gene analysis differentiates between Ureaplasma urealyticum and Ureaplasma parvum. Mycoplasma genitalium has become the third most frequent pathogen causing non-chlamydial, non-gonococcal urethritis (NCNGU); Ureaplasma urealyticum is less often isolated. Because urethritis caused by Mycoplasma genitalium does not always respond to tetracycline, it is advisable to begin therapy with a macrolide. Mycoplasma hominis is a cofactor for bacterial vaginosis and pelvic inflammatory disease (PID). During therapy with metronidazole, the colonization of this mycoplasma is decreased indirectly. PMID:19500195

  18. The bacterial gliding machinery

    NASA Astrophysics Data System (ADS)

    Shrivastava, Abhishek

    Cells of Flavobacterium johnsoniae, a rod-shaped bacterium, glide over surfaces with speeds reaching up to 2 micrometer's. Gliding is powered by a protonmotive force. The adhesin SprB forms filaments about 160 nm long that move on the cell-surface along a looped track. Interaction of SprB filaments with a surface produces gliding. We tethered F. johnsoniae cells to glass by adding anti-SprB antibody. Tethered cells spun about fixed points, rotating at speeds of about 1 Hz. The torques required to sustain such speeds were large, comparable to those generated by the flagellar rotary motor. Using a flow cell apparatus, we changed load on the gliding motor by adding the viscous agent Ficoll to tethered cells. We found that a gliding motor runs at constant speed rather than constant torque. We attached gold nanoparticles to the SprB filament and tracked its motion. We fluorescently tagged a bacterial Type IX secretion system (T9SS) protein and imaged its dynamics. Fluorescently tagged T9SS protein localized near the point of tether, indicating that T9SS localizes with the gliding motor. Based on our results, we propose a model to explain bacterial gliding.

  19. Motility of Mycoplasma pneumoniae.

    PubMed Central

    Radestock, U; Bredt, W

    1977-01-01

    Cell of Mycoplasma pneumoniae FH gliding on a glass surface in liquid medium were examined by microscopic observation and quantitatively by microcinematography (30 frames per min). Comparisons were made only within the individual experiments. The cells moved in an irregular pattern with numerous narrow bends and circles. They never changed their leading end. The average speed (without pauses) was relatively constant between o.2 and 0.5 mum/s. The maximum speed was about 1.5 to 2.0 mum/s. The movements were interrupted by resting periods of different lengths and frequency. Temperature, viscosity, pH, and the presence of yeast extract in the medium influenced the motility significantly; changes in glucose, calcium ions, and serum content were less effective. The movements were affected by iodoacetate, p-mercuribenzoate, and mitomycin C at inhibitory or subinhibitory concentrations. Sodium fluoride, sodium cyanide, dinitrophenol, chloramphenicol, puromycin, cholchicin, and cytochalasin B at minimal inhibitory concentrations did not affect motility. The movements were effectively inhibited by anti-M. pneumoniae antiserum. Studies with absorbed antiserum suggested that the surface components involved in motility are heat labile. The gliding of M. pneumoniae cells required an intact energy metabolism and the proteins involved seemed to have a low turnover. Images PMID:14925

  20. Mycoplasma pneumonia

    MedlinePlus

    ... Blood tests Bronchoscopy CT scan of the chest Open lung biopsy (only done in very serious illnesses when the diagnosis cannot be made from other sources) Sputum culture to check for mycoplasma bacteria

  1. First identification of proteins involved in motility of Mycoplasma gallisepticum.

    PubMed

    Indikova, Ivana; Vronka, Martin; Szostak, Michael P

    2014-01-01

    Mycoplasma gallisepticum, the most pathogenic mycoplasma in poultry, is able to glide over solid surfaces. Although this gliding motility was first observed in 1968, no specific protein has yet been shown to be involved in gliding. We examined M. gallisepticum strains and clonal variants for motility and found that the cytadherence proteins GapA and CrmA were required for gliding. Loss of GapA or CrmA resulted in the loss of motility and hemadsorption and led to drastic changes in the characteristic flask-shape of the cells. To identify further genes involved in motility, a transposon mutant library of M. gallisepticum was generated and screened for motility-deficient mutants, using a screening assay based on colony morphology. Motility-deficient mutants had transposon insertions in gapA and the neighbouring downstream gene crmA. In addition, insertions were seen in gene mgc2, immediately upstream of gapA, in two motility-deficient mutants. In contrast to the GapA/CrmA mutants, the mgc2 motility mutants still possessed the ability to hemadsorb. Complementation of these mutants with a mgc2-hexahistidine fusion gene restored the motile phenotype. This is the first report assigning specific M. gallisepticum proteins to involvement in gliding motility. PMID:25323771

  2. Hydrodynamic glide efficiency in swimming.

    PubMed

    Naemi, Roozbeh; Easson, William J; Sanders, Ross H

    2010-07-01

    The glide is a major part of starts, turns and the stroke cycle in breaststroke. Glide performance, indicated by the average velocity, can be improved by increasing the glide efficiency, that is, the ability of the body to minimise deceleration. This paper reviews the factors that affect glide efficiency. In the first part of the review the sources of resistive force are reviewed including surface friction (skin drag), pressure (form) drag and resistance due to making waves (wave drag). The effect of body surface characteristics on the skin drag, the effect of the depth of the swimmer on wave drag, and the effects of posture and alignment, body size and shape on the form drag are reviewed. The effects of these variables on the added mass, that is, the mass of water entrained with the body are explained. The 'glide factor' as a measure of glide efficiency that takes into account the combined effect of the resistive force and the added mass is described. In the second part methods of quantifying the resistive force are reviewed. Finally, the 'hydro-kinematic method' of measuring glide efficiency is evaluated. PMID:19540161

  3. In Vitro Spatial and Temporal Analysis of Mycoplasma pneumoniae Colonization of Human Airway Epithelium

    PubMed Central

    Prince, Oliver A.; Krunkosky, Thomas M.

    2014-01-01

    Mycoplasma pneumoniae is an important cause of respiratory disease, especially in school-age children and young adults. We employed normal human bronchial epithelial (NHBE) cells in air-liquid interface culture to study the interaction of M. pneumoniae with differentiated airway epithelium. These airway cells, when grown in air-liquid interface culture, polarize, form tight junctions, produce mucus, and develop ciliary function. We examined both qualitatively and quantitatively the role of mycoplasma gliding motility in the colonization pattern of developing airway cells, comparing wild-type M. pneumoniae and mutants thereof with moderate to severe defects in gliding motility. Adherence assays with radiolabeled mycoplasmas demonstrated a dramatic reduction in binding for all strains with airway cell polarization, independent of acquisition of mucociliary function. Adherence levels dropped further once NHBE cells achieved terminal differentiation, with mucociliary activity strongly selecting for full gliding competence. Analysis over time by confocal microscopy demonstrated a distinct colonization pattern that appeared to originate primarily with ciliated cells, but lateral spread from the base of the cilia was slower than expected. The data support a model in which the mucociliary apparatus impairs colonization yet cilia provide a conduit for mycoplasma access to the host cell surface and suggest acquisition of a barrier function, perhaps associated with tethered mucin levels, with NHBE cell polarization. PMID:24478073

  4. Similarities and differences between gliding glow and gliding arc discharges

    NASA Astrophysics Data System (ADS)

    Kolev, St.; Bogaerts, A.

    2015-12-01

    In this work we have analyzed the properties of a gliding dc discharge in argon at atmospheric pressure. Despite the usual designation of these discharges as ‘gliding arc discharges’, it was found previously that they operate in two different regimes—glow and arc. Here we analyze the differences in both regimes by means of two dimensional fluid modeling. In order to address different aspects of the discharge operation, we use two models—Cartesian and axisymmetric in a cylindrical coordinate system. The obtained results show that the two types of discharges produce a similar plasma column for a similar discharge current. However, the different mechanisms of plasma channel attachment to the cathode could produce certain differences in the plasma parameters (i.e. arc elongation), and this can affect gas treatments applications.

  5. Bacteria that glide with helical tracks

    PubMed Central

    Nan, Beiyan; McBride, Mark J.; Chen, Jing; Zusman, David R.; Oster, George

    2014-01-01

    Many bacteria glide smoothly on surfaces, but with no discernable propulsive organelles on their surface. Recent experiments with Myxococcus xanthus and Flavobacterium johnsoniae show that both distantly related bacterial species glide utilizing proteins that move in helical tracks, albeit with significantly different motility mechanisms. Both species utilize proton motive force for movement. However, the motors that power gliding in M. xanthus have been identified, while the F. johnsoniae motors remain to be discovered. PMID:24556443

  6. Radial gravitational gliding on passive margins

    NASA Astrophysics Data System (ADS)

    Cobbold, P. R.; Szatmari, P.

    1991-03-01

    Gravitational gliding of uppermost sediments down a passive margin is possible if there is a basal layer of evaporite or other soft material to allow detachment. In examples from the Gulf of Mexico and the Brazilian margin, gliding has produced three main structural domains: an uppermost domain of downdip extension; an intermediate domain of rigid gliding; and a lowermost domain of downdip contraction. Domain boundaries are established by changes in slope. In this paper, we examine three kinds of gravitational gliding, depending on the paths followed by material particles. In ideal parallel gliding, particle paths are parallel straight lines, trending downslope. This should occur where the margin is perfectly straight. In ideal radial gliding, particle paths are radii of a circle and the margin is shaped like a circular cone. Natural margins will not have ideal shapes; but divergent gliding will tend to occur off coastal salients; convergent gliding, off coastal re-entrants. A simple kinematic model based on ductile behaviour illustrates some essential features of radial gliding. Changes in radius during divergent gliding produce strike-parallel extension; during convergent gliding, they produce strike-parallel contraction. Vertical strains also differ. Divergent gliding produces an uppermost domain of strong vertical thinning, balanced by extensions in all horizontal directions. Similarly, convergent gliding produces a lowermost domain of strong vertical thickening, balanced by contractions in all horizontal directions. These deformed states cannot be restored by simple techniques based on section balancing. We have done three experiments using analogue materials: sand, to model the brittle behaviour of sediments; silicone putty, to model the ductile behaviour of basal layers of evaporite. The experiments were properly scaled to account for gravitational forces. Experiment I reproduced convergent gliding above a basement with a conical upper surface. Strike

  7. Glides and Phonological Change in Mombasan Swahili.

    ERIC Educational Resources Information Center

    Kelly, John

    1991-01-01

    A study of the pronunciation of an adult male Swahili speaker, a native and long-term resident of Mombasa Old Town, supplemented with notes on other adult speakers, suggests a new account of glides and phonological change in this variation of the language. The asymmetrical distribution of the two glide types (palatal and labiovelar) is analyzed…

  8. New model of flap-gliding flight.

    PubMed

    Sachs, Gottfried

    2015-07-21

    A new modelling approach is presented for describing flap-gliding flight in birds and the associated mechanical energy cost of travelling. The new approach is based on the difference in the drag characteristics between flapping and non-flapping due to the drag increase caused by flapping. Thus, the possibility of a gliding flight phase, as it exists in flap-gliding flight, yields a performance advantage resulting from the decrease in the drag when compared with continuous flapping flight. Introducing an appropriate non-dimensionalization for the mathematical relations describing flap-gliding flight, results and findings of generally valid nature are derived. It is shown that there is an energy saving of flap-gliding flight in the entire speed range compared to continuous flapping flight. The energy saving reaches the highest level in the lower speed region. The travelling speed of flap-gliding flight is composed of the weighted average of the differing speeds in the flapping and gliding phases. Furthermore, the maximum range performance achievable with flap-gliding flight and the associated optimal travelling speed are determined. PMID:25841702

  9. Glide performance and aerodynamics of non-equilibrium glides in northern flying squirrels (Glaucomys sabrinus).

    PubMed

    Bahlman, Joseph W; Swartz, Sharon M; Riskin, Daniel K; Breuer, Kenneth S

    2013-03-01

    Gliding is an efficient form of travel found in every major group of terrestrial vertebrates. Gliding is often modelled in equilibrium, where aerodynamic forces exactly balance body weight resulting in constant velocity. Although the equilibrium model is relevant for long-distance gliding, such as soaring by birds, it may not be realistic for shorter distances between trees. To understand the aerodynamics of inter-tree gliding, we used direct observation and mathematical modelling. We used videography (60-125 fps) to track and reconstruct the three-dimensional trajectories of northern flying squirrels (Glaucomys sabrinus) in nature. From their trajectories, we calculated velocities, aerodynamic forces and force coefficients. We determined that flying squirrels do not glide at equilibrium, and instead demonstrate continuously changing velocities, forces and force coefficients, and generate more lift than needed to balance body weight. We compared observed glide performance with mathematical simulations that use constant force coefficients, a characteristic of equilibrium glides. Simulations with varying force coefficients, such as those of live squirrels, demonstrated better whole-glide performance compared with the theoretical equilibrium state. Using results from both the observed glides and the simulation, we describe the mechanics and execution of inter-tree glides, and then discuss how gliding behaviour may relate to the evolution of flapping flight. PMID:23256188

  10. Glide performance and aerodynamics of non-equilibrium glides in northern flying squirrels (Glaucomys sabrinus)

    PubMed Central

    Bahlman, Joseph W.; Swartz, Sharon M.; Riskin, Daniel K.; Breuer, Kenneth S.

    2013-01-01

    Gliding is an efficient form of travel found in every major group of terrestrial vertebrates. Gliding is often modelled in equilibrium, where aerodynamic forces exactly balance body weight resulting in constant velocity. Although the equilibrium model is relevant for long-distance gliding, such as soaring by birds, it may not be realistic for shorter distances between trees. To understand the aerodynamics of inter-tree gliding, we used direct observation and mathematical modelling. We used videography (60–125 fps) to track and reconstruct the three-dimensional trajectories of northern flying squirrels (Glaucomys sabrinus) in nature. From their trajectories, we calculated velocities, aerodynamic forces and force coefficients. We determined that flying squirrels do not glide at equilibrium, and instead demonstrate continuously changing velocities, forces and force coefficients, and generate more lift than needed to balance body weight. We compared observed glide performance with mathematical simulations that use constant force coefficients, a characteristic of equilibrium glides. Simulations with varying force coefficients, such as those of live squirrels, demonstrated better whole-glide performance compared with the theoretical equilibrium state. Using results from both the observed glides and the simulation, we describe the mechanics and execution of inter-tree glides, and then discuss how gliding behaviour may relate to the evolution of flapping flight. PMID:23256188

  11. Distribution and diversity of mycoplasma plasmids: lessons from cryptic genetic elements

    PubMed Central

    2012-01-01

    Background The evolution of mycoplasmas from a common ancestor with Firmicutes has been characterized not only by genome down-sizing but also by horizontal gene transfer between mycoplasma species sharing a common host. The mechanisms of these gene transfers remain unclear because our knowledge of the mycoplasma mobile genetic elements is limited. In particular, only a few plasmids have been described within the Mycoplasma genus. Results We have shown that several species of ruminant mycoplasmas carry plasmids that are members of a large family of elements and replicate via a rolling-circle mechanism. All plasmids were isolated from species that either belonged or were closely related to the Mycoplasma mycoides cluster; none was from the Mycoplasma bovis-Mycoplasma agalactiae group. Twenty one plasmids were completely sequenced, named and compared with each other and with the five mycoplasma plasmids previously reported. All plasmids share similar size and genetic organization, and present a mosaic structure. A peculiar case is that of the plasmid pMyBK1 from M. yeatsii; it is larger in size and is predicted to be mobilizable. Its origin of replication and replication protein were identified. In addition, pMyBK1 derivatives were shown to replicate in various species of the M. mycoides cluster, and therefore hold considerable promise for developing gene vectors. The phylogenetic analysis of these plasmids confirms the uniqueness of pMyBK1 and indicates that the other mycoplasma plasmids cluster together, apart from the related replicons found in phytoplasmas and in species of the clade Firmicutes. Conclusions Our results unraveled a totally new picture of mycoplasma plasmids. Although they probably play a limited role in the gene exchanges that participate in mycoplasma evolution, they are abundant in some species. Evidence for the occurrence of frequent genetic recombination strongly suggests they are transmitted between species sharing a common host or niche. PMID

  12. 14 CFR 171.267 - Glide path automatic monitor system.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Glide path automatic monitor system. 171... Landing System (ISMLS) § 171.267 Glide path automatic monitor system. (a) The ISMLS glide path equipment... control points when any of the following occurs: (1) A shift of the mean ISMLS glide path angle...

  13. 14 CFR 171.267 - Glide path automatic monitor system.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Glide path automatic monitor system. 171... Landing System (ISMLS) § 171.267 Glide path automatic monitor system. (a) The ISMLS glide path equipment... control points when any of the following occurs: (1) A shift of the mean ISMLS glide path angle...

  14. 14 CFR 171.267 - Glide path automatic monitor system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Glide path automatic monitor system. 171... Landing System (ISMLS) § 171.267 Glide path automatic monitor system. (a) The ISMLS glide path equipment... control points when any of the following occurs: (1) A shift of the mean ISMLS glide path angle...

  15. 14 CFR 171.267 - Glide path automatic monitor system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Glide path automatic monitor system. 171... Landing System (ISMLS) § 171.267 Glide path automatic monitor system. (a) The ISMLS glide path equipment... control points when any of the following occurs: (1) A shift of the mean ISMLS glide path angle...

  16. 14 CFR 171.267 - Glide path automatic monitor system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Glide path automatic monitor system. 171... Landing System (ISMLS) § 171.267 Glide path automatic monitor system. (a) The ISMLS glide path equipment... control points when any of the following occurs: (1) A shift of the mean ISMLS glide path angle...

  17. A Mesozoic gliding mammal from northeastern China.

    PubMed

    Meng, Jin; Hu, Yaoming; Wang, Yuanqing; Wang, Xiaolin; Li, Chuankui

    2006-12-14

    Gliding flight has independently evolved many times in vertebrates. Direct evidence of gliding is rare in fossil records and is unknown in mammals from the Mesozoic era. Here we report a new Mesozoic mammal from Inner Mongolia, China, that represents a previously unknown group characterized by a highly specialized insectivorous dentition and a sizable patagium (flying membrane) for gliding flight. The patagium is covered with dense hair and supported by an elongated tail and limbs; the latter also bear many features adapted for arboreal life. This discovery extends the earliest record of gliding flight for mammals to at least 70 million years earlier in geological history, and demonstrates that early mammals were diverse in their locomotor strategies and lifestyles; they had experimented with an aerial habit at about the same time as, if not earlier than, when birds endeavoured to exploit the sky. PMID:17167478

  18. Antibacterial activity of aquatic gliding bacteria.

    PubMed

    Sangnoi, Yutthapong; Anantapong, Theerasak; Kanjana-Opas, Akkharawit

    2016-01-01

    The study aimed to screen and isolate strains of freshwater aquatic gliding bacteria, and to investigate their antibacterial activity against seven common pathogenic bacteria. Submerged specimens were collected and isolated for aquatic gliding bacteria using four different isolation media (DW, MA, SAP2, and Vy/2). Gliding bacteria identification was performed by 16S rRNA gene sequencing and phylogenetic analysis. Crude extracts were obtained by methanol extraction. Antibacterial activity against seven pathogenic bacteria was examined by agar-well diffusion assay. Five strains of aquatic gliding bacteria including RPD001, RPD008, RPD018, RPD027 and RPD049 were isolated. Each submerged biofilm and plastic specimen provided two isolates of gliding bacteria, whereas plant debris gave only one isolate. Two strains of gliding bacteria were obtained from each DW and Vy/2 isolation medium, while one strain was obtained from the SAP2 medium. Gliding bacteria strains RPD001, RPD008 and RPD018 were identified as Flavobacterium anhuiense with 96, 82 and 96 % similarity, respectively. Strains RPD049 and RPD027 were identified as F. johnsoniae and Lysobacter brunescens, respectively, with similarity equal to 96 %. Only crude extract obtained from RPD001 inhibited growth of Listeria monocytogenes (MIC 150 µg/ml), Staphylococcus aureus (MIC 75 µg/ml) and Vibrio cholerae (MIC 300 µg/ml), but showed weak inhibitory effect on Salmonella typhimurium (MIC > 300 µg/ml). Gliding bacterium strain RPD008 should be considered to a novel genus separate from Flavobacterium due to its low similarity value. Crude extract produced by RPD001 showed potential for development as a broad antibiotic agent. PMID:26885469

  19. Mycoplasma bovis research update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycoplasma bovis in bison is a newly emerging and potentially devastating threat to the bison industry. This bacterium is increasingly being identified, both in the United States and Canada, as the cause of severe respiratory disease outbreaks with devastating consequences for the health of the ani...

  20. Rapid imaging of mycoplasma in solution using Atmospheric Scanning Electron Microscopy (ASEM)

    SciTech Connect

    Sato, Chikara; Manaka, Sachie; Nakane, Daisuke; Nishiyama, Hidetoshi; Suga, Mitsuo; Nishizaka, Takayuki; Miyata, Makoto; Maruyama, Yuusuke

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer Mycoplasma mobile was observed in buffer with the Atmospheric Scanning Electron Microscope. Black-Right-Pointing-Pointer Characteristic protein localizations were visualized using immuno-labeling. Black-Right-Pointing-Pointer M. mobile attached to sialic acid on the SiN film surface within minutes. Black-Right-Pointing-Pointer Cells were observed at low concentrations. Black-Right-Pointing-Pointer ASEM should promote study and early-stage diagnosis of mycoplasma. -- Abstract: Mycoplasma is a genus of bacterial pathogen that causes disease in vertebrates. In humans, the species Mycoplasma pneumoniae causes 15% or more of community-acquired pneumonia. Because this bacterium is tiny, corresponding in size to a large virus, diagnosis using optical microscopy is not easy. In current methods, chest X-rays are usually the first action, followed by serology, PCR amplification, and/or culture, but all of these are particularly difficult at an early stage of the disease. Using Mycoplasma mobile as a model species, we directly observed mycoplasma in buffer with the newly developed Atmospheric Scanning Electron Microscope (ASEM). This microscope features an open sample dish with a pressure-resistant thin film window in its base, through which the SEM beam scans samples in solution, from below. Because of its 2-3 {mu}m-deep scanning capability, it can observe the whole internal structure of mycoplasma cells stained with metal solutions. Characteristic protein localizations were visualized using immuno-labeling. Cells were observed at low concentrations, because suspended cells concentrate in the observable zone by attaching to sialic acid on the silicon nitride (SiN) film surface within minutes. These results suggest the applicability of the ASEM for the study of mycoplasmas as well as for early-stage mycoplasma infection diagnosis.

  1. 14 CFR 171.265 - Glide path performance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Glide path performance requirements. 171... Landing System (ISMLS) § 171.265 Glide path performance requirements. This section prescribes the performance requirements for glide path equipment components of the ISMLS. These requirements are based on...

  2. Aerodynamic Characteristics and Glide-Back Performance of Langley Glide-Back Booster

    NASA Technical Reports Server (NTRS)

    Pamadi, Bandu N.; Covell, Peter F.; Tartabini, Paul V.; Murphy, Kelly J.

    2004-01-01

    NASA-Langley Research Center is conducting system level studies on an-house concept of a small launch vehicle to address NASA's needs for rapid deployment of small payloads to Low Earth Orbit. The vehicle concept is a three-stage system with a reusable first stage and expendable upper stages. The reusable first stage booster, which glides back to launch site after staging around Mach 3 is named the Langley Glide-Back Booster (LGBB). This paper discusses the aerodynamic characteristics of the LGBB from subsonic to supersonic speeds, development of the aerodynamic database and application of this database to evaluate the glide back performance of the LGBB. The aerodynamic database was assembled using a combination of wind tunnel test data and engineering level analysis. The glide back performance of the LGBB was evaluated using a trajectory optimization code and subject to constraints on angle of attack, dynamic pressure and normal acceleration.

  3. Investigation of gliding flight by flying fish

    NASA Astrophysics Data System (ADS)

    Park, Hyungmin; Jeon, Woo-Pyung; Choi, Haecheon

    2006-11-01

    The most successful flight capability of fish is observed in the flying fish. Furthermore, despite the difference between two medium (air and water), the flying fish is well evolved to have an excellent gliding performance as well as fast swimming capability. In this study, flying fish's morphological adaptation to gliding flight is experimentally investigated using dry-mounted darkedged-wing flying fish, Cypselurus Hiraii. Specifically, we examine the effects of the pectoral and pelvic fins on the aerodynamic performance considering (i) both pectoral and pelvic fins, (ii) pectoral fins only, and (iii) body only with both fins folded. Varying the attack angle, we measure the lift, drag and pitching moment at the free-stream velocity of 12m/s for each case. Case (i) has higher lift-to-drag ratio (i.e. longer gliding distance) and more enhanced longitudinal static stability than case (ii). However, the lift coefficient is smaller for case (i) than for case (ii), indicating that the pelvic fins are not so beneficial for wing loading. The gliding performance of flying fish is compared with those of other fliers and is found to be similar to those of insects such as the butterfly and fruitfly.

  4. The driving force for glide of a threading dislocation in a strained epitaxial layer on a substrate

    NASA Astrophysics Data System (ADS)

    Freund, L. B.

    T HE PROCESS of epitaxial growth of a very thin layer onto a substrate crystal is considered for the particular situation in which the layer and substrate materials have the same crystal structure and orientation but different lattice parameters. Under these conditions, the layer grows with an intrinsic elastic strain determined by the mismatch in lattice parameters. The associated stress in the crystalline layer provides a driving force for the nucleation and motion of defects, primarily dislocations. The focus here is on the glide of a dislocation extending from the free surface of the layer to the layer-substrate interface, the so-called threading dislocation. A general definition of driving force for glide of a threading dislocation is introduced on the basis of work arguments. The definition is then applied to calculate the driving force for steady motion of an isolated threading dislocation in a strained layer, and the result includes Matthews' critical thickness concept as one of its features. Next, a kinetic equation for glide of a dislocation in semiconductor materials is proposed to estimate the glide rate of a threading dislocation in these low mobility materials. Finally, for the case of cubic materials, the general definition of driving force is applied to estimate the additional driving force on a threading dislocation due to an encounter with a dislocation on an intersecting glide plane. The results indicate that this effect is significant in blocking the glide of a threading dislocation for large mismatch strains and for layer thicknesses near the critical thickness.

  5. The Phospholipid Profile of Mycoplasmas

    PubMed Central

    Kornspan, Jonathan D.; Rottem, Shlomo

    2012-01-01

    The de novo synthesized polar lipids of Mycoplasma species are rather simple, comprising primarily of the acidic glycerophospholipids PG and CL. In addition, when grown in a medium containing serum, significant amounts of PC and SPM are incorporated into the mycoplasma cell membrane although these lipids are very uncommon in wall-covered bacteria. The exogenous lipids are either incorporated unchanged or the PC incorporated is modified by a deacylation-acylation enzymatic cycle to form disaturated PC. Although their small genome, in some Mycoplasma species, other genes involved in lipid biosynthesis were detected, resulting in the synthesis of a variety of glycolipis, phosphoglycolipids and ether lipids. We suggest that analyses and comparisons of mycoplasma polar lipids may serve as a novel and useful tool for classification. Nonetheless, to evaluate the importance of polar lipids in mycoplasma, further systematic and extensive studies on more Mycoplasma species are needed. While studies are needed to elucidate the role of lipids in the mechanisms governing the interaction of mycoplasmas with host eukaryotic cells, the finding that a terminal phosphocholine containing glycolipids of M. fermentans serves both as a major immune determinants and as a trigger of the inflammatory responses, and the findings that the fusogenicity of M. fermentans with host cells is markedly stimulated by lyso-ether lipids, are important steps toward understanding the molecular mechanisms of M. fermentans pathogenicity. PMID:22848839

  6. Animal model of Mycoplasma fermentans respiratory infection

    PubMed Central

    2013-01-01

    Background Mycoplasma fermentans has been associated with respiratory, genitourinary tract infections and rheumatoid diseases but its role as pathogen is controversial. The purpose of this study was to probe that Mycoplasma fermentans is able to produce respiratory tract infection and migrate to several organs on an experimental infection model in hamsters. One hundred and twenty six hamsters were divided in six groups (A-F) of 21 hamsters each. Animals of groups A, B, C were intratracheally injected with one of the mycoplasma strains: Mycoplasma fermentans P 140 (wild strain), Mycoplasma fermentans PG 18 (type strain) or Mycoplasma pneumoniae Eaton strain. Groups D, E, F were the negative, media, and sham controls. Fragments of trachea, lungs, kidney, heart, brain and spleen were cultured and used for the histopathological study. U frequency test was used to compare recovery of mycoplasmas from organs. Results Mycoplasmas were detected by culture and PCR. The three mycoplasma strains induced an interstitial pneumonia; they also migrated to several organs and persisted there for at least 50 days. Mycoplasma fermentans P 140 induced a more severe damage in lungs than Mycoplasma fermentans PG 18. Mycoplasma pneumoniae produced severe damage in lungs and renal damage. Conclusions Mycoplasma fermentans induced a respiratory tract infection and persisted in different organs for several weeks in hamsters. This finding may help to explain the ability of Mycoplasma fermentans to induce pneumonia and chronic infectious diseases in humans. PMID:23298636

  7. Rapid imaging of mycoplasma in solution using Atmospheric Scanning Electron Microscopy (ASEM).

    PubMed

    Sato, Chikara; Manaka, Sachie; Nakane, Daisuke; Nishiyama, Hidetoshi; Suga, Mitsuo; Nishizaka, Takayuki; Miyata, Makoto; Maruyama, Yuusuke

    2012-01-27

    Mycoplasma is a genus of bacterial pathogen that causes disease in vertebrates. In humans, the species Mycoplasma pneumoniae causes 15% or more of community-acquired pneumonia. Because this bacterium is tiny, corresponding in size to a large virus, diagnosis using optical microscopy is not easy. In current methods, chest X-rays are usually the first action, followed by serology, PCR amplification, and/or culture, but all of these are particularly difficult at an early stage of the disease. Using Mycoplasma mobile as a model species, we directly observed mycoplasma in buffer with the newly developed Atmospheric Scanning Electron Microscope (ASEM). This microscope features an open sample dish with a pressure-resistant thin film window in its base, through which the SEM beam scans samples in solution, from below. Because of its 2-3μm-deep scanning capability, it can observe the whole internal structure of mycoplasma cells stained with metal solutions. Characteristic protein localizations were visualized using immuno-labeling. Cells were observed at low concentrations, because suspended cells concentrate in the observable zone by attaching to sialic acid on the silicon nitride (SiN) film surface within minutes. These results suggest the applicability of the ASEM for the study of mycoplasmas as well as for early-stage mycoplasma infection diagnosis. PMID:22226908

  8. Sterol requirement of Mycoplasma capricolum.

    PubMed Central

    Odriozola, J M; Waitzkin, E; Smith, T L; Bloch, K

    1978-01-01

    Mycoplasmas require an external source of sterol for growth. For Mycoplasma capricolum this requirement is met not only by cholesterol but also by the methylcholestane derivatives lanosterol, cycloartenol, 4,4-dimethylcholesterol, and 4beta-methylcholestanol. Cholesteryl methyl ether and 3alpha-methylcholestanol serve equally well as sterol supplements. None of the growth-supporting sterol derivatives tested was metabolically modified. The unusual acceptance of diverse cholestane derivatives by a mycoplasma species contrasts with the structural attributes thought to be necessary for sterol function in eukaryotic membranes. PMID:279900

  9. Uncovering the Mystery of Gliding Motility in the Myxobacteria

    PubMed Central

    Nan, Beiyan; Zusman, David R.

    2012-01-01

    Bacterial gliding motility is the smooth movement of cells on solid surfaces unaided by flagella or pili. Many diverse groups of bacteria exhibit gliding, but the mechanism of gliding motility has remained a mystery since it was first observed more than a century ago. Recent studies on the motility of Myxococcus xanthus, a soil myxobacterium, suggest a likely mechanism for gliding in this organism. About forty M. xanthus genes were shown to be involved in gliding motility, and some of their protein products were labeled and localized within cells. These studies suggest that gliding motility in M. xanthus involves large multiprotein structural complexes, regulatory proteins, and cytoskeletal filaments. In this review, we summarize recent experiments that provide the basis for this emerging view of M. xanthus motility. We also discuss alternative models for gliding. PMID:21910630

  10. Systematic Structural Analyses of Attachment Organelle in Mycoplasma pneumoniae

    PubMed Central

    Matsuo, Lisa; Miyata, Makoto

    2015-01-01

    Mycoplasma pneumoniae, a human pathogenic bacterium, glides on host cell surfaces by a unique and unknown mechanism. It forms an attachment organelle at a cell pole as a membrane protrusion composed of surface and internal structures, with a highly organized architecture. In the present study, we succeeded in isolating the internal structure of the organelle by sucrose-gradient centrifugation. The negative-staining electron microscopy clarified the details and dimensions of the internal structure, which is composed of terminal button, paired plates, and bowl complex from the end of cell front. Peptide mass fingerprinting of the structure suggested 25 novel components for the organelle, and 3 of them were suggested for their involvement in the structure through their subcellular localization determined by enhanced yellow fluorescent protein (EYFP) tagging. Thirteen component proteins including the previously reported ones were mapped on the organelle systematically for the first time, in nanometer order by EYFP tagging and immunoelectron microscopy. Two, three, and six specific proteins localized specifically to the terminal button, the paired plates, and the bowl, respectively and interestingly, HMW2 molecules were aligned parallel to form the plate. The integration of these results gave the whole image of the organelle and allowed us to discuss possible gliding mechanisms. PMID:26633540

  11. On complex, curved trajectories in microtubule gliding

    NASA Astrophysics Data System (ADS)

    Gosselin, Pierre; Mohrbach, Hervé; Kulić, Igor M.; Ziebert, Falko

    2016-04-01

    We study the dynamics of microtubules in gliding assays. These biofilaments are typically considered as purely semiflexible, hence their trajectories under the action of motors covering the substrate have been regarded so far as straight, modulo fluctuations. However, this is not always the case experimentally, where microtubules are known to move on large scale circles or spirals, or even display quite regular wavy trajectories and more complex dynamics. Incorporating recent experimental evidence for a (small) preferred curvature as well as the microtubules' well established lattice twist into a dynamic model for microtubule gliding, we could reproduce both types of trajectories. Interestingly, as a function of the microtubules' length we found length intervals of stable rings alternating with regions where wavy and more complex dynamics prevails. Finally, both types of dynamics (rings and waves) can be rationalized by considering simple limits of the full model.

  12. Optical diagnostics of a gliding arc.

    PubMed

    Sun, Z W; Zhu, J J; Li, Z S; Aldén, M; Leipold, F; Salewski, M; Kusano, Y

    2013-03-11

    Dynamic processes in a gliding arc plasma generated between two diverging electrodes in ambient air driven by 31.25 kHz AC voltage were investigated using spatially and temporally resolved optical techniques. The life cycles of the gliding arc were tracked in fast movies using a high-speed camera with framing rates of tens to hundreds of kHz, showing details of ignition, motion, pulsation, short-cutting, and extinction of the plasma column. The ignition of a new discharge occurs before the extinction of the previous discharge. The developed, moving plasma column often short-cuts its current path triggered by Townsend breakdown between the two legs of the gliding arc. The emission from the plasma column is shown to pulsate at a frequency of 62.5 kHz, i.e., twice the frequency of the AC power supply. Optical emission spectra of the plasma radiation show the presence of excited N2, NO and OH radicals generated in the plasma and the dependence of their relative intensities on both the distance relative to the electrodes and the phase of the driving AC power. Planar laser-induced fluorescence of the ground-state OH radicals shows high intensity outside the plasma column rather than in the center suggesting that ground-state OH is not formed in the plasma column but in its vicinity. PMID:23482171

  13. Assessing the importance of terrain parameters on glide avalanche release

    USGS Publications Warehouse

    Peitzsch, Erich H.; Hendrikx, Jordy; Fagre, Daniel B.

    2014-01-01

    Glide snow avalanches are dangerous and difficult to predict. Despite recent research there is still a lack of understanding regarding the controls of glide avalanche release. Glide avalanches often occur in similar terrain or the same locations annually and observations suggest that topography may be critical. Thus, to gain an understanding of the terrain component of these types of avalanches we examined terrain parameters associated with glide avalanche release as well as areas of consistent glide crack formation but no subsequent avalanches. Glide avalanche occurrences visible from the Going-to-the-Sun Road corridor in Glacier National Park, Montana from 2003-2013 were investigated using an avalanche database derived of daily observations each year from April 1 to June 15. This yielded 192 glide avalanches in 53 distinct avalanche paths. Each avalanche occurrence was digitized in a GIS using satellite, oblique, and aerial imagery as reference. Topographical parameters such as area, slope, aspect, elevation and elevation were then derived for the entire dataset utilizing GIS tools and a 10m DEM. Land surface substrate and surface geology were derived from National Park Service Inventory and Monitoring maps and U.S. Geological Survey surface geology maps, respectively. Surface roughness and glide factor were calculated using a four level classification index. . Then, each avalanche occurrence was aggregated to general avalanche release zones and the frequencies were compared. For this study, glide avalanches released in elevations ranging from 1300 to 2700 m with a mean aspect of 98 degrees (east) and a mean slope angle of 38 degrees. The mean profile curvature for all glide avalanches was 0.15 and a plan curvature of -0.01, suggesting a fairly linear surface (i.e. neither convex nor concave). The glide avalanches occurred in mostly bedrock made up of dolomite and limestone slabs and talus deposits with very few occurring in alpine meadows. However, not all glide

  14. LEDS theory of workhardening stages and planar versus distributed glide

    NASA Astrophysics Data System (ADS)

    Kuhlmann-Wilsdorf, D.; Wilsdorf, H. G. F.; Wert, J. A.

    1994-09-01

    From a widespread convention, glide in crystalline materials is classified as 'planar' versus 'distributed'. At elevated temperatures, 'distributed glide' is favored and is almost usually found at medium to high strains in pure metals, in low-concentration homogeneous alloys, and in a preponderance of multiphase alloys, provided temperatures are not too low. While at low temperatures, 'planar glide' is widely observed and favored in solid solution alloys. In this paper, a general explanation is presented over the proposed additional causes for planar versus distributed glide, based on the LEDS theory.

  15. Phase field modeling of a glide dislocation transmission across a coherent sliding interface

    NASA Astrophysics Data System (ADS)

    Zheng, Songlin; Ni, Yong; He, Linghui

    2015-04-01

    Three-dimensional phase field microelasticity modeling and simulation capable of representing core structure and elastic interactions of dislocations are used to study a glide dislocation transmission across a coherent sliding interface in face-centered cubic metals. We investigate the role of the interface sliding process, which is described as the reversible motion of interface dislocation on the interfacial barrier strength to transmission. Numerical results show that a wider transient interface sliding zone develops on the interface with a lower interfacial unstable stacking fault energy to trap the glide dislocation leading to a stronger barrier to transmission. The interface sliding zone shrinks in the case of high applied stress and low mobility for the interfacial dislocation. This indicates that such interfacial barrier strength might be rate dependent. We discuss the calculated interfacial barrier strength for the Cu/Ni interface from the contribution of interface sliding comparable to previous atomistic simulations.

  16. Spreading Factors of Mycoplasma alligatoris, a Flesh-Eating Mycoplasma

    PubMed Central

    Brown, D. R.; Zacher, L. A.; Farmerie, W. G.

    2004-01-01

    Mycoplasma alligatoris causes lethal invasive disease of alligators and caimans. A homolog of the nagH gene, encoding a hyaluronidase secreted by Clostridium perfringens, and a C. perfringens hyaluronidase nagI or nagK pseudogene were discovered in the M. alligatoris genome. The nagH gene was detected by PCR in the closest relative of M. alligatoris, Mycoplasma crocodyli, but not in 40 other species representing the Mycoplasma hominis, Mycoplasma pneumoniae, and Spiroplasma phylogenetic clusters. The hyaluronidase activity in the cellular fraction of M. alligatoris and M. crocodyli SP4 broth cultures was equivalent to 10−16 U of Streptomyces hyalurolyticus hyaluronidase CFU−1. Negligible activity was present in the cell-free supernatant fraction. No chondroitinase activity was detected. There is also a novel homolog of the nanI gene, which encodes a sialidase secreted by C. perfringens, in the M. alligatoris genome. The signature YRIP and SXDXGXTW motifs and catalytic residues of the clostridial sialidase are conserved in the mycoplasmal gene, but the leader sequence necessary for its secretion by C. perfringens is absent. The gene was not detected by PCR in any other mycoplasma. Potent cell-associated sialidase activity was present in M. alligatoris colonies on agar but not in the cell-free supernatants of broth cultures or in M. crocodyli. The presence of hyaluronidase and sialidase in M. alligatoris is consistent with the rapid invasiveness and necrotizing effects of this organism, and the lack of sialidase in M. crocodyli is consistent with its comparatively attenuated virulence. This genetic and biochemical evidence suggests that the spreading factors hyaluronidase and sialidase, a combination unprecedented in mycoplasmas, are the basis of the virulence of M. alligatoris. PMID:15175306

  17. 14 CFR 171.265 - Glide path performance requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Glide path performance requirements. 171.265 Section 171.265 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) NAVIGATIONAL FACILITIES NON-FEDERAL NAVIGATION FACILITIES Interim Standard Microwave Landing System (ISMLS) § 171.265 Glide...

  18. 14 CFR 23.71 - Glide: Single-engine airplanes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Glide: Single-engine airplanes. 23.71... Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical miles... with the engine inoperative, its propeller in the minimum drag position, and landing gear and...

  19. 14 CFR 23.71 - Glide: Single-engine airplanes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Glide: Single-engine airplanes. 23.71... Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical miles... with the engine inoperative, its propeller in the minimum drag position, and landing gear and...

  20. 14 CFR 23.71 - Glide: Single-engine airplanes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Glide: Single-engine airplanes. 23.71... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Flight Performance § 23.71 Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical...

  1. 14 CFR 23.71 - Glide: Single-engine airplanes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Glide: Single-engine airplanes. 23.71... Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical miles... with the engine inoperative, its propeller in the minimum drag position, and landing gear and...

  2. 14 CFR 23.71 - Glide: Single-engine airplanes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Glide: Single-engine airplanes. 23.71... Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical miles... with the engine inoperative, its propeller in the minimum drag position, and landing gear and...

  3. Polyradiculoneuritis and Mycoplasma pneumoniae infection.

    PubMed

    Holt, S; Khan, M M; Charles, R G; Epstein, E J

    1977-07-01

    A patient with severe Mycoplasma pneumonia developed polyradiculoneuritis and respiratory failure. The acute phase of the illness was complicated by a myocarditis, and recovery of neurological function was slow. Residual left hemidiaphragmatic paralysis was present 1 year after onset of the illness. PMID:882485

  4. Draft Genome Sequence of "Candidatus Mycoplasma haemobos," a Hemotropic Mycoplasma Identified in Cattle in Mexico.

    PubMed

    Martínez-Ocampo, Fernando; Rodríguez-Camarillo, Sergio D; Amaro-Estrada, Itzel; Quiroz-Castañeda, Rosa Estela

    2016-01-01

    We present here the draft genome sequence of the first "Candidatus Mycoplasma haemobos" strain found in cattle in Mexico. This hemotropic mycoplasma causes acute and chronic disease in animals. This genome is a starting point for studying the role of this mycoplasma in coinfections and synergistic mechanisms associated with the disease. PMID:27389272

  5. An Efficient Implementation of the Gliding Box Lacunarity Algorithm

    SciTech Connect

    Charles R. Tolle,; Timothy R. McJunkin; David J. Gorsich

    2008-03-01

    Lacunarity is a measure of how data fills space. It complements fractal dimension, which measures how much space is filled. Currently, many researchers use the gliding box algorithm for calculating lacunarity. This paper introduces a fast algorithm for making this calculation. The algorithm presented is akin to fast box counting algorithms used by some researchers in estimating fractal dimension. A simplified gliding box measure equation along with key pseudo code implementations for the algorithm are presented. Applications for the gliding box lacunarity measure have included subjects that range from biological community modeling to target detection.

  6. Degradation of Verapamil hydrochloride in water by gliding arc discharge.

    PubMed

    Krishna, Syam; Maslani, Alan; Izdebski, Tomasz; Horakova, Marta; Klementova, Sarka; Spatenka, Petr

    2016-06-01

    This study investigated the influence of gliding arc plasma discharge on the degradation of Verapamil hydrochloride in water. The plasma discharge was characterized by means of optical emission spectroscopy. Spectra of various atomic and molecular species were observed. Aqueous solution of Verapamil hydrochloride was exposed to gliding arc discharge operated in continuous discharge at atmospheric pressure and room temperature. The identification of Verapamil, the degradation mechanisms of Verapamil and its transformation products were performed using liquid chromatography - mass spectrometry (HPLC-MS). Experimental results indicate that the atmospheric pressure gliding arc plasma treatment has noticeable effects on Verapamil with satisfactory degradation efficiency. Plausible mechanisms of the degradation were discussed. PMID:26953731

  7. Substrate-induced gliding in a nematic liquid crystal layer

    NASA Astrophysics Data System (ADS)

    Mema, E.; Kondic, L.; Cummings, L. J.

    2015-12-01

    We consider the interaction between nematic liquid crystals (NLCs) and polymer substrates. Such substrates can interact with NLCs, exhibiting a phenomenon known as director gliding: the preferred orientation of the NLC molecules at the interface changes on time scales that are slow relative to the elastic relaxation time scale of the NLC. We present two models for gliding, inspired by experiments that investigate the interaction between the NLC and a polymer substrate. These models, though simple, lead to nontrivial results, including loss of bistability under gliding. Perhaps surprisingly, we find that externally imposed switching between the steady states of a bistable system may reverse the effect of gliding, preventing loss of bistability if switching is sufficiently frequent. Our findings may be of relevance to a variety of technological applications involving liquid crystal devices, and particularly to a new generation of flexible liquid crystal displays that implement polymeric substrates.

  8. Substrate-induced gliding in a nematic liquid crystal layer.

    PubMed

    Mema, E; Kondic, L; Cummings, L J

    2015-12-01

    We consider the interaction between nematic liquid crystals (NLCs) and polymer substrates. Such substrates can interact with NLCs, exhibiting a phenomenon known as director gliding: the preferred orientation of the NLC molecules at the interface changes on time scales that are slow relative to the elastic relaxation time scale of the NLC. We present two models for gliding, inspired by experiments that investigate the interaction between the NLC and a polymer substrate. These models, though simple, lead to nontrivial results, including loss of bistability under gliding. Perhaps surprisingly, we find that externally imposed switching between the steady states of a bistable system may reverse the effect of gliding, preventing loss of bistability if switching is sufficiently frequent. Our findings may be of relevance to a variety of technological applications involving liquid crystal devices, and particularly to a new generation of flexible liquid crystal displays that implement polymeric substrates. PMID:26764717

  9. Molecular Biology and Pathogenicity of Mycoplasmas

    PubMed Central

    Razin, Shmuel; Yogev, David; Naot, Yehudith

    1998-01-01

    The recent sequencing of the entire genomes of Mycoplasma genitalium and M. pneumoniae has attracted considerable attention to the molecular biology of mycoplasmas, the smallest self-replicating organisms. It appears that we are now much closer to the goal of defining, in molecular terms, the entire machinery of a self-replicating cell. Comparative genomics based on comparison of the genomic makeup of mycoplasmal genomes with those of other bacteria, has opened new ways of looking at the evolutionary history of the mycoplasmas. There is now solid genetic support for the hypothesis that mycoplasmas have evolved as a branch of gram-positive bacteria by a process of reductive evolution. During this process, the mycoplasmas lost considerable portions of their ancestors’ chromosomes but retained the genes essential for life. Thus, the mycoplasmal genomes carry a high percentage of conserved genes, greatly facilitating gene annotation. The significant genome compaction that occurred in mycoplasmas was made possible by adopting a parasitic mode of life. The supply of nutrients from their hosts apparently enabled mycoplasmas to lose, during evolution, the genes for many assimilative processes. During their evolution and adaptation to a parasitic mode of life, the mycoplasmas have developed various genetic systems providing a highly plastic set of variable surface proteins to evade the host immune system. The uniqueness of the mycoplasmal systems is manifested by the presence of highly mutable modules combined with an ability to expand the antigenic repertoire by generating structural alternatives, all compressed into limited genomic sequences. In the absence of a cell wall and a periplasmic space, the majority of surface variable antigens in mycoplasmas are lipoproteins. Apart from providing specific antimycoplasmal defense, the host immune system is also involved in the development of pathogenic lesions and exacerbation of mycoplasma induced diseases. Mycoplasmas are

  10. Mycoplasmas, plants, insect vectors: a matrimonial triangle.

    PubMed

    Garnier, M; Foissac, X; Gaurivaud, P; Laigret, F; Renaudin, J; Saillard, C; Bové, J M

    2001-10-01

    Plant pathogenic mycoplasmas were discovered by electron microscopy, in 1967, long after the discovery and culture in 1898 of the first pathogenic mycoplasma of animal origin, Mycoplasma mycoides. Mycoplasmas are Eubacteria of the class Mollicutes, a group of organisms phylogenetically related to Gram-positive bacteria. Their more characteristic features reside in the small size of their genomes, the low guanine (G) plus cytosine (C) content of their genomic DNA and the lack of a cell wall. Plant pathogenic mycoplasmas are responsible for several hundred diseases and belong to two groups: the phytoplasmas and the spiroplasmas. The phytoplasmas (previously called MLOs, for mycoplasma like organisms) were discovered first; they are pleiomorphic, and have so far resisted in vitro cultivation. Phytoplasmas represent the largest group of plant pathogenic Mollicutes. Only three plant pathogenic spiroplasmas are known today. Spiroplasma citri, the agent of citrus stubborn was discovered and cultured in 1970 and shown to be helical and motile. S. kunkelii is the causal agent of corn stunt. S. phoeniceum, responsible for periwinkle yellows, was discovered in Syria. There are many other spiroplasmas associated with insects and ticks. Plant pathogenic mycoplasmas are restricted to the phloem sieve tubes in which circulates the photosynthetically-enriched sap, the food for many phloem-feeding insects (aphids, leafhoppers, psyllids, etc.). Interestingly, phytopathogenic mycoplasmas are very specifically transmitted by leafhoppers or psyllid species. In this paper, the most recent knowledge on phytopathogenic mycoplasmas in relation with their insect and plant habitats is presented as well as the experiments carried out to control plant mycoplasma diseases, by expression of mycoplasma-directed-antibodies in plants (plantibodies). PMID:11570280

  11. Antimicrobial susceptibility of Mycoplasma hyorhinis.

    PubMed

    Wu, C C; Shryock, T R; Lin, T L; Faderan, M; Veenhuizen, M F

    2000-09-15

    A broth microdilution technique was used to determine the antimicrobial susceptibility of 15 field isolates of Mycoplasma hyorhinis to 10 antimicrobial agents, representative of different classes, and contrasting newer agents to existing ones. For the macrolides, the MIC(90) for tylosin and tilmicosin was 1 and 4 microg/ml, respectively, but was > or = 16 microg/ml for erythromycin. Tetracycline, lincomycin and enrofloxacin each had an MIC(90) of 2 microg/ml. The mycoplasma had similar levels of susceptibility to the aminoglycoside and aminocyclictol classes exhibiting an MIC(90) of 4 microg/ml for gentamicin and 2 microg/ml for spectinomycin. The isolates exhibited high MICs to trimethoprim/sulfamethoxazole with an MIC(90) > or = 16/304 microg/ml. In summary, M. hyorhinis isolates from the US had low MICs against a variety of antimicrobials tested, with the exception of erythromycin and trimethoprim/sulfamethoxazole. PMID:10925038

  12. 21 CFR 610.30 - Test for Mycoplasma.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Test for Mycoplasma. 610.30 Section 610.30 Food... GENERAL BIOLOGICAL PRODUCTS STANDARDS Mycoplasma § 610.30 Test for Mycoplasma. Except as provided... tested for the presence of Mycoplasma, as follows: Samples of the virus for this test shall be...

  13. 21 CFR 610.30 - Test for Mycoplasma.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Test for Mycoplasma. 610.30 Section 610.30 Food and... GENERAL BIOLOGICAL PRODUCTS STANDARDS Mycoplasma § 610.30 Test for Mycoplasma. Except as provided... tested for the presence of Mycoplasma, as follows: Samples of the virus for this test shall be...

  14. Soaring energetics and glide performance in a moving atmosphere.

    PubMed

    Taylor, Graham K; Reynolds, Kate V; Thomas, Adrian L R

    2016-09-26

    Here, we analyse the energetics, performance and optimization of flight in a moving atmosphere. We begin by deriving a succinct expression describing all of the mechanical energy flows associated with gliding, dynamic soaring and thermal soaring, which we use to explore the optimization of gliding in an arbitrary wind. We use this optimization to revisit the classical theory of the glide polar, which we expand upon in two significant ways. First, we compare the predictions of the glide polar for different species under the various published models. Second, we derive a glide optimization chart that maps every combination of headwind and updraft speed to the unique combination of airspeed and inertial sink rate at which the aerodynamic cost of transport is expected to be minimized. With these theoretical tools in hand, we test their predictions using empirical data collected from a captive steppe eagle (Aquila nipalensis) carrying an inertial measurement unit, global positioning system, barometer and pitot tube. We show that the bird adjusts airspeed in relation to headwind speed as expected if it were seeking to minimize its aerodynamic cost of transport, but find only weak evidence to suggest that it adjusts airspeed similarly in response to updrafts during straight and interthermal glides.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. PMID:27528788

  15. Electrical charging of skis gliding on snow.

    PubMed

    Colbeck, S C

    1995-01-01

    Ski charging was measured using giant-slalom style skis as gliding capacitors. The voltage measured across the plates was proportional to the charge on the base. While resting on dry snow or suspended in the air, the voltage was slowly reduced by the data logger itself. On wet snow the decay was much faster. While stationary on powder snow the ski developed a slightly negative voltage, showed a small, transient positive peak when motion began, rapidly dropped to negative values, and then assumed a quasi-steady climb to positive voltages. A great deal of noise was superimposed on the general features of the signal when skiing on hard or bumpy surfaces. Thus, the accumulation of charge to high levels was only possible with long runs in deep powder. The rate of charging increased with speed but was not affected by use of one "antistatic" wax, and another such wax actually increased the measured voltage over that of an unwaxed base. PMID:7898330

  16. Mycoplasma genitalium in Toronto, Ont

    PubMed Central

    Gesink, Dionne; Racey, C. Sarai; Seah, Christine; Zittermann, Sandra; Mitterni, Leo; Juzkiw, Jerry; Jamieson, Heather; Greer, Jane; Singh, Sudesh; Jensen, Jørgen Skov; Allen, Vanessa

    2016-01-01

    Objective To estimate the prevalence of Mycoplasma genitalium in Toronto, Ont; detect mutations associated with macrolide and fluoroquinolone resistance; and describe treatment outcomes. Design Prospective, cross-sectional study. Setting A sexual health clinic in Toronto. Participants A consecutive sample of men and women attending the sexual health clinic between September 1, 2013, and December 20, 2013. Interventions Participants underwent testing for M genitalium, along with standard sexually transmitted infection screening. All samples that had positive results for M genitalium were tested for mutations associated with resistance to macrolides and fluoroquinolones. Mycoplasma genitalium treatment was based on resistance profile and verified with a test of cure. Main outcome measures Positive results for M genitalium and antibiotic resistance. Results A total of 1193 men and women participated in the study. Overall, 4.5% of the 884 men and 3.2% of the 309 women had positive test results for M genitalium. Asymptomatic infection was common (52.0%). Macrolide resistance–mediating mutations were found in 58.0% of the M genitalium infections. No treatment failure was observed for azithromycin-treated cases. Treatment failure was suspected for 16.7% of cases treated with moxifloxacin. Conclusion Mycoplasma genitalium is present in Canada, with a prevalence comparable to chlamydia and gonorrhea, and has high macrolide and fluoroquinolone resistance. PMID:27331225

  17. Flow Cytometric Determination of the Effects of Antibacterial Agents on Mycoplasma agalactiae, Mycoplasma putrefaciens, Mycoplasma capricolum subsp. capricolum, and Mycoplasma mycoides subsp. mycoides Large Colony Type

    PubMed Central

    Assunção, Patricia; Antunes, Nuno T.; Rosales, Ruben S.; Poveda, Carlos; Poveda, Jose B.; Davey, Hazel M.

    2006-01-01

    Flow cytometry together with SYBR green I and propidium iodide was used to study the effects of enrofloxacin, ciprofloxacin, gentamicin, chloramphenicol, oxytetracycline, and tylosin on four mycoplasma species. Inhibition of mycoplasma growth could be detected by as early as 3 h after the start of treatment. The strongest effect was observed with enrofloxacin- and ciprofloxacin-treated cells. PMID:16870783

  18. Recent Advances in Mycoplasma gallisepticum Vaccine Administration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Application of live Mycoplasma gallisepticum vaccines to layer chickens generally occurs at 9 to 10 weeks of age. Mycoplasma organisms are extremely fastidious in the laboratory and difficult to grow. Very little attention has been accorded to optimizing parameters for vaccine administration in th...

  19. Gliding Motility in Bacteria: Insights from Studies of Myxococcus xanthus

    PubMed Central

    Spormann, Alfred M.

    1999-01-01

    Gliding motility is observed in a large variety of phylogenetically unrelated bacteria. Gliding provides a means for microbes to travel in environments with a low water content, such as might be found in biofilms, microbial mats, and soil. Gliding is defined as the movement of a cell on a surface in the direction of the long axis of the cell. Because this definition is operational and not mechanistic, the underlying molecular motor(s) may be quite different in diverse microbes. In fact, studies on the gliding bacterium Myxococcus xanthus suggest that two independent gliding machineries, encoded by two multigene systems, operate in this microorganism. One machinery, which allows individual cells to glide on a surface, independent of whether the cells are moving alone or in groups, requires the function of the genes of the A-motility system. More than 37 A-motility genes are known to be required for this form of movement. Depending on an additional phenotype, these genes are divided into two subclasses, the agl and cgl genes. Videomicroscopic studies on gliding movement, as well as ultrastructural observations of two myxobacteria, suggest that the A-system motor may consist of multiple single motor elements that are arrayed along the entire cell body. Each motor element is proposed to be localized to the periplasmic space and to be anchored to the peptidoglycan layer. The force to glide which may be generated here is coupled to adhesion sites that move freely in the outer membrane. These adhesion sites provide a specific contact with the substratum. Based on single-cell observations, similar models have been proposed to operate in the unrelated gliding bacteria Flavobacterium johnsoniae (formerly Cytophaga johnsonae), Cytophaga strain U67, and Flexibacter polymorphus (a filamentous glider). Although this model has not been verified experimentally, M. xanthus seems to be the ideal organism with which to test it, given the genetic tools available. The second gliding

  20. Co-infection with Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' in three cats from Brazil.

    PubMed

    de Morais, Helio A; Guimarães, Ana Marcia S; Vidotto, Odilon; Baumann, Aline; Biondo, Alexander W; Messick, Joanne B

    2007-12-01

    The two most common haemotropic Mycoplasma of cats, Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' have been identified using molecular techniques in all continents, except Antarctica. We report the first molecular characterization in South America of a dual infection with M haemofelis and 'Candidatus Mycoplasma haemominutum' in three domestic cats. The 16S ribosomal RNA gene was amplified in three anaemic cats in which haemoplasma organisms were seen attached to the erythrocytes in the peripheral blood smear. Bands of the expected size for M haemofelis and 'Candidatus Mycoplasma haemominutum' were observed in all three cats. The 393 bp segment of one of the amplicons had a similarity value of 100% to M haemofelis, whereas the other amplicon, a 192 bp segment, was 100% similar to 'Candidatus Mycoplasma haemominutum'. After diagnosis, two cats received blood transfusion and they were all treated with doxycycline. All three cats recovered uneventfully. PMID:17693111

  1. GLobal Integrated Design Environment (GLIDE): A Concurrent Engineering Application

    NASA Technical Reports Server (NTRS)

    McGuire, Melissa L.; Kunkel, Matthew R.; Smith, David A.

    2010-01-01

    The GLobal Integrated Design Environment (GLIDE) is a client-server software application purpose-built to mitigate issues associated with real time data sharing in concurrent engineering environments and to facilitate discipline-to-discipline interaction between multiple engineers and researchers. GLIDE is implemented in multiple programming languages utilizing standardized web protocols to enable secure parameter data sharing between engineers and researchers across the Internet in closed and/or widely distributed working environments. A well defined, HyperText Transfer Protocol (HTTP) based Application Programming Interface (API) to the GLIDE client/server environment enables users to interact with GLIDE, and each other, within common and familiar tools. One such common tool, Microsoft Excel (Microsoft Corporation), paired with its add-in API for GLIDE, is discussed in this paper. The top-level examples given demonstrate how this interface improves the efficiency of the design process of a concurrent engineering study while reducing potential errors associated with manually sharing information between study participants.

  2. Glide-Shuffle Competition in Silicon: An Atomistic Study

    NASA Astrophysics Data System (ADS)

    Li, Ju; Cai, Wei; Chang, Jinpeng; Yip, Sidney

    2001-06-01

    Glide-Shuffle Competition in Silicon: An Atomistic Study Ju Li, Wei Cai, Jinpeng Chang, Sidney Yip, Massachusetts Institute of Technology, Department of Nuclear Engineering, Cambridge, MA 02139 Recent experiments by Suzuki et al and Rabier et al suggest that low-T and high-T plasticity in Si and III-IV compounds may be governed by different mechanisms. We perform direct atomistic calculations to obtain the core energies, Peierls-Nabarro stresses, and kink formation and migration energies of full shuffle- and glide-set dislocations and glide-set partial dislocations in Si using the Stillinger-Weber potential. These results are compared with previous calculations, and their implications will be discussed. Dynamical simulations of some of the full dislocations in motion show qualitatively different behavior with their counterparts in bcc metals.

  3. A methodology for boost-glide transport technology planning

    NASA Technical Reports Server (NTRS)

    Repic, E. M.; Olson, G. A.; Milliken, R. J.

    1974-01-01

    A systematic procedure is presented by which the relative economic value of technology factors affecting design, configuration, and operation of boost-glide transport can be evaluated. Use of the methodology results in identification of first-order economic gains potentially achievable by projected advances in each of the definable, hypersonic technologies. Starting with a baseline vehicle, the formulas, procedures and forms which are integral parts of this methodology are developed. A demonstration of the methodology is presented for one specific boost-glide system.

  4. The descent of ant: field-measured performance of gliding ants.

    PubMed

    Munk, Yonatan; Yanoviak, Stephen P; Koehl, M A R; Dudley, Robert

    2015-05-01

    Gliding ants avoid predatory attacks and potentially mortal consequences of dislodgement from rainforest canopy substrates by directing their aerial descent towards nearby tree trunks. The ecologically relevant measure of performance for gliding ants is the ratio of net horizontal to vertical distance traveled over the course of a gliding trajectory, or glide index. To study variation in glide index, we measured three-dimensional trajectories of Cephalotes atratus ants gliding in natural rainforest habitats. We determined that righting phase duration, glide angle, and path directness all significantly influence variation in glide index. Unsuccessful landing attempts result in the ant bouncing off its target and being forced to make a second landing attempt. Our results indicate that ants are not passive gliders and that they exert active control over the aerodynamic forces they experience during their descent, despite their apparent lack of specialized control surfaces. PMID:25788722

  5. Mycoplasma penetrans bacteremia and primary antiphospholipid syndrome.

    PubMed Central

    Yáñez, A.; Cedillo, L.; Neyrolles, O.; Alonso, E.; Prévost, M. C.; Rojas, J.; Watson, H. L.; Blanchard, A.; Cassell, G. H.

    1999-01-01

    Mycoplasma penetrans, a rare bacterium so far only found in HIV-infected persons, was isolated in the blood and throat of a non-HIV-infected patient with primary antiphospholipid syndrome (whose etiology and pathogenesis are unknown). PMID:10081687

  6. A College Epidemic of Mycoplasma Pneumoniae.

    ERIC Educational Resources Information Center

    Ralston, David; Cochran, Burt

    1979-01-01

    The article reports on an outbreak of mycoplasma pneumoniae at the California Polytechnic State University including a historical background of the disease, clinical features, laboratory findings for treated patients, treatment, and clinical clues for diagnosis. (JMF)

  7. Detection and prevention of mycoplasma hominis infection

    DOEpatents

    DelVecchio, Vito G.; Gallia, Gary L.; McCleskey, Ferne K.

    1997-01-21

    The present invention is directed to a rapid and sensitive method for detecting Mycoplasma hominis using M. hominis-specific probes, oligonucleotides or antibodies. In particular a target sequence can be amplified by in vitro nucleic acid amplification techniques, detected by nucleic acid hybridization using the subject probes and oligonucleotides or detected by immunoassay using M. hominis-specific antibodies. M. hominis-specific nucleic acids which do not recognize or hybridize to genomic nucleic acid of other Mycoplasma species are also provided.

  8. Choline-containing lipids in mycoplasmas.

    PubMed

    Rottem, Shlomo

    2002-07-01

    Choline-containing lipids were identified and characterized in the cell membrane of Mycoplasma fermentans and were shown to participate in the adhesion to the surface of eukaryotic cells, to stimulate mycoplasma fusion with eukaryotic cells, and to induce cytokine secretion by cells of the immune system. These findings suggest that choline-containing lipids are important mediators of tissue pathology in the infectious process caused by M. fermentans. PMID:12106789

  9. Evidence for Type III Restriction and Modification Systems in Mycoplasma pulmonis▿

    PubMed Central

    Dybvig, Kevin; Cao, Z.; French, C. Todd; Yu, Huilan

    2007-01-01

    Mycoplasma pulmonis possesses a cassette of genes that are predicted to code for type III restriction and modification (R-M) enzymes. Transposon disruption of a gene predicted to code for the endonuclease subunit of the enzyme resulted in loss of R-M activity. Genomic data indicate that the cassette was acquired by horizontal gene transfer and possibly located on a mobile element. PMID:17209015

  10. Mycoplasmas and Ureaplasmas as Neonatal Pathogens

    PubMed Central

    Waites, Ken B.; Katz, Brenda; Schelonka, Robert L.

    2005-01-01

    The genital mycoplasmas represent a complex and unique group of microorganisms that have been associated with a wide array of infectious diseases in adults and infants. The lack of conclusive knowledge regarding the pathogenic potential of Mycoplasma and Ureaplasma spp. in many conditions is due to a general unfamiliarity of physicians and microbiology laboratories with their fastidious growth requirements, leading to difficulty in their detection; their high prevalence in healthy persons; the poor design of research studies attempting to base association with disease on the mere presence of the organisms in the lower urogenital tract; the failure to consider multifactorial aspects of diseases; and considering these genital mycoplasmas only as a last resort. The situation is now changing because of a greater appreciation of the genital mycoplasmas as perinatal pathogens and improvements in laboratory detection, particularly with regard to the development of powerful molecular nucleic acid amplification tests. This review summarizes the epidemiology of genital mycoplasmas as causes of neonatal infections and premature birth; evidence linking ureaplasmas with bronchopulmonary dysplasia; recent changes in the taxonomy of the genus Ureaplasma; the neonatal host response to mycoplasma and ureaplasma infections; advances in laboratory detection, including molecular methods; and therapeutic considerations for treatment of systemic diseases. PMID:16223956

  11. Illusory Continuity without Sufficient Sound Energy to Fill a Temporal Gap: Examples of Crossing Glide Tones

    ERIC Educational Resources Information Center

    Kuroda, Tsuyoshi; Nakajima, Yoshitaka; Eguchi, Shuntarou

    2012-01-01

    The gap transfer illusion is an auditory illusion where a temporal gap inserted in a longer glide tone is perceived as if it were in a crossing shorter glide tone. Psychophysical and phenomenological experiments were conducted to examine the effects of sound-pressure-level (SPL) differences between crossing glides on the occurrence of the gap…

  12. EXPERIMENTAL INFECTION OF THE RESPIRATORY TRACT WITH MYCOPLASMA PNEUMONIAE

    EPA Science Inventory

    Mycoplasma pneumoniae, a common human respiratory pathogen, has been studied experimentally for years using intranasal inoculation of the golden Sytrian hamster. Because of recent evidence outlining the role in pulmonary immune development of particle size and depth of mycoplasma...

  13. Dynamics of discrete screw dislocations on glide directions

    NASA Astrophysics Data System (ADS)

    Alicandro, R.; De Luca, L.; Garroni, A.; Ponsiglione, M.

    2016-07-01

    We consider a simple discrete model for screw dislocations in crystals. Using a variational discrete scheme we study the motion of a configuration of dislocations toward low energy configurations. We deduce an effective fully overdamped dynamics that follows the maximal dissipation criterion introduced in Cermelli and Gurtin (1999) and predicts motion along the glide directions of the crystal.

  14. 14 CFR 171.265 - Glide path performance requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Glide path performance requirements. 171.265 Section 171.265 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Amplitude (DDM) (95 pct. probability) Outer limit of coverage to ISMLS point “C.” 0.035. The...

  15. 14 CFR 171.265 - Glide path performance requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Glide path performance requirements. 171.265 Section 171.265 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Amplitude (DDM) (95 pct. probability) Outer limit of coverage to ISMLS point “C.” 0.035. The...

  16. 14 CFR 171.265 - Glide path performance requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Glide path performance requirements. 171.265 Section 171.265 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Amplitude (DDM) (95 pct. probability) Outer limit of coverage to ISMLS point “C.” 0.035. The...

  17. Kick, Glide, Pole! Cross-Country Skiing Fun (Part II)

    ERIC Educational Resources Information Center

    Duoos, Bridget A.

    2012-01-01

    Part I of Kick, Glide, Pole! Cross-Country Skiing Fun, which was published in last issue, discussed how to select cross-country ski equipment, dress for the activity and the biomechanics of the diagonal stride. Part II focuses on teaching the diagonal stride technique and begins with a progression of indoor activities. Incorporating this fun,…

  18. Gliding swifts attain laminar flow over rough wings.

    PubMed

    Lentink, David; de Kat, Roeland

    2014-01-01

    Swifts are among the most aerodynamically refined gliding birds. However, the overlapping vanes and protruding shafts of their primary feathers make swift wings remarkably rough for their size. Wing roughness height is 1-2% of chord length on the upper surface--10,000 times rougher than sailplane wings. Sailplanes depend on extreme wing smoothness to increase the area of laminar flow on the wing surface and minimize drag for extended glides. To understand why the swift does not rely on smooth wings, we used a stethoscope to map laminar flow over preserved wings in a low-turbulence wind tunnel. By combining laminar area, lift, and drag measurements, we show that average area of laminar flow on swift wings is 69% (n = 3; std 13%) of their total area during glides that maximize flight distance and duration--similar to high-performance sailplanes. Our aerodynamic analysis indicates that swifts attain laminar flow over their rough wings because their wing size is comparable to the distance the air travels (after a roughness-induced perturbation) before it transitions from laminar to turbulent. To interpret the function of swift wing roughness, we simulated its effect on smooth model wings using physical models. This manipulation shows that laminar flow is reduced and drag increased at high speeds. At the speeds at which swifts cruise, however, swift-like roughness prolongs laminar flow and reduces drag. This feature gives small birds with rudimentary wings an edge during the evolution of glide performance. PMID:24964089

  19. Gliding Swifts Attain Laminar Flow over Rough Wings

    PubMed Central

    Lentink, David; de Kat, Roeland

    2014-01-01

    Swifts are among the most aerodynamically refined gliding birds. However, the overlapping vanes and protruding shafts of their primary feathers make swift wings remarkably rough for their size. Wing roughness height is 1–2% of chord length on the upper surface—10,000 times rougher than sailplane wings. Sailplanes depend on extreme wing smoothness to increase the area of laminar flow on the wing surface and minimize drag for extended glides. To understand why the swift does not rely on smooth wings, we used a stethoscope to map laminar flow over preserved wings in a low-turbulence wind tunnel. By combining laminar area, lift, and drag measurements, we show that average area of laminar flow on swift wings is 69% (n = 3; std 13%) of their total area during glides that maximize flight distance and duration—similar to high-performance sailplanes. Our aerodynamic analysis indicates that swifts attain laminar flow over their rough wings because their wing size is comparable to the distance the air travels (after a roughness-induced perturbation) before it transitions from laminar to turbulent. To interpret the function of swift wing roughness, we simulated its effect on smooth model wings using physical models. This manipulation shows that laminar flow is reduced and drag increased at high speeds. At the speeds at which swifts cruise, however, swift-like roughness prolongs laminar flow and reduces drag. This feature gives small birds with rudimentary wings an edge during the evolution of glide performance. PMID:24964089

  20. Evaluation of snow-glide risk by modelling and on-site assessment

    NASA Astrophysics Data System (ADS)

    Leitinger, Georg; Meusburger, Katrin; Rüdisser, Johannes; Tasser, Erich; Höller, Peter

    2015-04-01

    Abandonment of agricultural practices on alpine grasslands lead to increasing snow-glide intensities due to lower surface roughness of the vegetation. Beneath the danger of snow-glide avalanches snow gliding leads to soil erosion and damaging of young trees at afforested sites. Especially in high altitudes afforestation is important to protect settlements and infrastructure against snow-gliding and glide avalanches. Snow-glide damages are therefore of particular danger for these afforestation sites. In the light of future climate change and warmer winter periods, studies already state increasing snow-glide risk and the occurrence of glide avalanches. This study presents an approach to evaluate snow-glide risk by combining the refined Spatial Snow Glide Model (SSGM) first published by Leitinger et al. (2008) and the Guidelines to Identify Snow-Glide Areas (GISGA) proposed by Höller (2012), an on-site risk analyses approach. First, GISGA was validated on the basis of corresponding snow-glide measurements. Second, a potential snow-glide map for an area in the Eastern Alps covering 20000 km² was modelled. The results revealed considerable areas of high snow-glide risk. Using the average amount of winter precipitation between 1990 and 2010 in the SSGM shows higher vulnerability for the northern part of the study area (Tyrol, Austria) than in the southern part (South Tyrol, Italy) because of lower winter precipitation. However, running the SSGM based on the highest winter precipitation registered in the study area between 1801 and 2003 exhibits the possibility of very high snow-glide risk for most parts of the study area with significant increasing risk in the southern part. Given the very probable future climate during winter periods with increasing temperatures but uncertain development of precipitation patterns, snow-glide activity and linked glide avalanches might further increase at least in areas and altitudes with solid precipitation. In combination with the

  1. Membrane lipids of Mycoplasma fermentans.

    PubMed

    Salman, M; Deutsch, I; Tarshis, M; Naot, Y; Rottem, S

    1994-11-01

    Membranes of Mycoplasma fermentans, incognitus strain, were isolated by a combination of osmotic lysis and sonication. Analysis of membrane lipids revealed, in addition to free and esterified cholesterol, six major polar lipids dominated by a de novo synthesized compound (compound X), which accounts for 64% of the total lipid phosphorus. Compound X was labeled by palmitate, but not by oleate. Mass spectrometry and gas liquid chromatography analyses of compound X revealed two molecular species with molecular masses of 1048 and 1076 representing, a dipalmitoyl- and a stearoyl-palmitoyl-glycerodiphosphatidylcholine. Compound X has the ability to stimulate human monocytes to secret TNF alpha and to enhance the fusion of small unilamellar vesicles with MOLT-3 lymphocytes. PMID:7988908

  2. Adaptive glide slope control for parafoil and payload aircraft

    NASA Astrophysics Data System (ADS)

    Ward, Michael

    Airdrop systems provide a unique capability of delivering large payloads to undeveloped and inaccessible locations. Traditionally, these systems have been unguided, requiring large landing zones and drops from low altitude. The invention of the steerable, gliding, ram-air parafoil enabled the possibility of precision aerial payload delivery. In practice, the gliding ability of the ram-air parafoil can actually create major problems for airdrop systems by making them more susceptible to winds and allowing them to achieve far greater miss distances than were previously possible. Research and development work on guided airdrop systems has focused primarily on evolutionary improvements to the guidance algorithm, while the navigation and control algorithms have changed little since the initial autnomous systems were developed. Furthermore, the control mechanisms have not changed since the invention of the ram-air canopy in the 1960’s. The primary contributions of this dissertation are: (1) the development of a reliable and robust method to identify a flight dynamic model for a parafoil and payload aircraft using minimal sensor data; (2) the first demonstration in flight test of the ability to achieve large changes in glide slope over ground using coupled incidence angle variation and trailing edge brake deflection; (3) the first development of a control law to implement glide slope control on an autonomous system; (4) the first flight tests of autonomous landing with a glide slope control mechanism demonstrating an improvement in landing accuracy by a factor of 2 or more in especially windy conditions, and (5) the first demonstrations in both simulation and flight test of the ability to perform in-flight system identification to adapt the internal control mappings to flight data and provide dramatic improvements in landing accuracy when there is a significant discrepancy between the assumed and actual flight characteristics.

  3. The enigma of eugregarine epicytic folds: where gliding motility originates?

    PubMed Central

    2013-01-01

    Background In the past decades, many studies focused on the cell motility of apicomplexan invasive stages as they represent a potential target for chemotherapeutic intervention. Gregarines (Conoidasida, Gregarinasina) are a heterogeneous group that parasitize invertebrates and urochordates, and are thought to be an early branching lineage of Apicomplexa. As characteristic of apicomplexan zoites, gregarines are covered by a complicated pellicle, consisting of the plasma membrane and the closely apposed inner membrane complex, which is associated with a number of cytoskeletal elements. The cell cortex of eugregarines, the epicyte, is more complicated than that of other apicomplexans, as it forms various superficial structures. Results The epicyte of the eugregarines, Gregarina cuneata, G. polymorpha and G. steini, analysed in the present study is organised in longitudinal folds covering the entire cell. In mature trophozoites and gamonts, each epicytic fold exhibits similar ectoplasmic structures and is built up from the plasma membrane, inner membrane complex, 12-nm filaments, rippled dense structures and basal lamina. In addition, rib-like myonemes and an ectoplasmic network are frequently observed. Under experimental conditions, eugregarines showed varied speeds and paths of simple linear gliding. In all three species, actin and myosin were associated with the pellicle, and this actomyosin complex appeared to be restricted to the lateral parts of the epicytic folds. Treatment of living gamonts with jasplakinolide and cytochalasin D confirmed that actin actively participates in gregarine gliding. Contributions to gliding of specific subcellular components are discussed. Conclusions Cell motility in gregarines and other apicomplexans share features in common, i.e. a three-layered pellicle, an actomyosin complex, and the polymerisation of actin during gliding. Although the general architecture and supramolecular organisation of the pellicle is not correlated with

  4. 21 CFR 610.30 - Test for Mycoplasma.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Test for Mycoplasma. 610.30 Section 610.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS GENERAL BIOLOGICAL PRODUCTS STANDARDS Mycoplasma § 610.30 Test for Mycoplasma. Except as provided otherwise in this subchapter, prior to...

  5. 21 CFR 610.30 - Test for Mycoplasma.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Test for Mycoplasma. 610.30 Section 610.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS GENERAL BIOLOGICAL PRODUCTS STANDARDS Mycoplasma § 610.30 Test for Mycoplasma. Except as...

  6. Draft Genome Sequence of “Candidatus Mycoplasma haemobos,” a Hemotropic Mycoplasma Identified in Cattle in Mexico

    PubMed Central

    Martínez-Ocampo, Fernando; Rodríguez-Camarillo, Sergio D.; Amaro-Estrada, Itzel

    2016-01-01

    We present here the draft genome sequence of the first “Candidatus Mycoplasma haemobos” strain found in cattle in Mexico. This hemotropic mycoplasma causes acute and chronic disease in animals. This genome is a starting point for studying the role of this mycoplasma in coinfections and synergistic mechanisms associated with the disease. PMID:27389272

  7. A comparison of glide force characteristics between 2 prefilled insulin lispro pens.

    PubMed

    Rees, Tina M; Lennartz, Amanda H; Ignaut, Debra A

    2015-03-01

    Glide force, average glide force, and glide force variability of the insulin lispro 200 units/mL pen (Eli Lilly and Company, Indianapolis, IN, USA) were compared to the Humalog KwikPen 100 units/mL pen (hereafter, KwikPen; Eli Lilly and Company, Indianapolis, IN, USA). Data were collected on 2 doses, 2 injection speeds, and 2 needle types. Insulin lispro 200 units/mL pen showed significantly lower maximum glide force, average glide force, and glide force variability than the KwikPen across all combinations of dose size, dose speed, and needle type. The lower glide force observed with the insulin lispro 200 units/mL pen offers another treatment option for patients with type 1 or type 2 diabetes who require greater than 20 units of mealtime insulin daily. PMID:25591858

  8. The gliding speed of migrating birds: slow and safe or fast and risky?

    PubMed

    Horvitz, Nir; Sapir, Nir; Liechti, Felix; Avissar, Roni; Mahrer, Isaac; Nathan, Ran

    2014-06-01

    Aerodynamic theory postulates that gliding airspeed, a major flight performance component for soaring avian migrants, scales with bird size and wing morphology. We tested this prediction, and the role of gliding altitude and soaring conditions, using atmospheric simulations and radar tracks of 1346 birds from 12 species. Gliding airspeed did not scale with bird size and wing morphology, and unexpectedly converged to a narrow range. To explain this discrepancy, we propose that soaring-gliding birds adjust their gliding airspeed according to the risk of grounding or switching to costly flapping flight. Introducing the Risk Aversion Flight Index (RAFI, the ratio of actual to theoretical risk-averse gliding airspeed), we found that inter- and intraspecific variation in RAFI positively correlated with wing loading, and negatively correlated with convective thermal conditions and gliding altitude, respectively. We propose that risk-sensitive behaviour modulates the evolution (morphology) and ecology (response to environmental conditions) of bird soaring flight. PMID:24641086

  9. The relationship between 3-D kinematics and gliding performance in the southern flying squirrel, Glaucomys volans.

    PubMed

    Bishop, Kristin L

    2006-02-01

    Gliding is the simplest form of flight, yet relatively little is known about its mechanics in animals. The goal of this study was to describe the body position and performance of a gliding mammal and to identify correlates between kinematics and aerodynamic performance. To do this, I used a pair of high-speed digital cameras to record a portion of the middle of glides by southern flying squirrels, Glaucomys volans. The squirrels launched from a height of 4 m and landed on a vertical pole. Reflective markers were applied to anatomical landmarks and the 3-D coordinates of these points were computed to describe the kinematics of the glides. From these data I estimated the lift and drag generated during the glide, and correlated these variables with gliding performance as measured by glide angle, glide speed and stability. In the majority of the glide sequences the squirrels accelerated in the downward direction and accelerated horizontally forward as they moved through the calibrated volume in the middle of the glide trajectory, rather than exhibiting a steady glide in which the body weight is balanced by the resultant aerodynamic force. Compared to human engineered airfoils, the angles of attack used by the squirrels were unexpectedly high, ranging from 35.4 degrees to 53.5 degrees , far above the angle of attack at which an aircraft wing would typically stall. As expected based on aerodynamic theory, there was a negative correlation between angle of attack and lift coefficient, indicating that the wings are stalled, and a positive correlation between angle of attack and drag coefficient. Also as expected, there was a negative correlation between lift-to-drag ratio and angle of attack, as increasing angle of attack produced both less lift and more drag. Within glides, there was a strong correlation between nose-down pitching rotations and limb movements that tended to increase the angle of attack of the wing membrane, suggesting that the animals actively control

  10. Eosinophilic Fasciitis Associated with Mycoplasma arginini Infection

    PubMed Central

    Silló, Pálma; Pintér, Dóra; Ostorházi, Eszter; Mazán, Mercedes; Wikonkál, Norbert; Pónyai, Katinka; Volokhov, Dmitriy V.; Chizhikov, Vladimir E.; Szathmary, Susan; Stipkovits, Laszlo

    2012-01-01

    Eosinophilic fasciitis (EF) with generalized sclerodermiform skin lesions developed over a 19-month period in a previously healthy 23-year-old man. Although we confirmed EF by skin histology and laboratory tests, the recurrent fevers and the clinical observation of sclerotic prepuce with urethritis indicated further bacteriological analysis by conventional microbiological and DNA-based tests. Urethra cultures were positive for an arginine-hydrolyzing mycoplasma and Ureaplasma urealyticum. The patient also had serum IgM antibodies to Mycoplasma pneumoniae using enzyme-linked immunosorbent assay (ELISA)-based qualitative detection. Mycoplasma arginini was isolated from two independent venous blood serum samples and was identified by conventional microbiological tests and sequencing of the 16S rRNA and rpoB genes (GenBank sequence accession numbers HM179555 and HM179556, respectively). M. arginini genomic DNA also was detected by species-specific PCR in the skin lesion biopsy sample. Treatment with corticosteroids and long-term courses of selected antibiotics led to remission of skin symptoms and normalization of laboratory values. This report provides the first evidence of EF associated with mycoplasma infection and the second report of human infection with M. arginini and therefore suggests that this mycoplasma infection might have contributed to the pathogenesis of the disease. PMID:22189109

  11. The occurrence of mycoplasmas in selected wild North American waterfowl

    USGS Publications Warehouse

    Goldberg, D.R.; Samuel, M.D.; Thomas, C.B.; Sharp, P.; Krapu, G.L.; Robb, J.R.; Kenow, K.P.; Korschgen, C.E.; Chipley, W.H.; Conroy, M.J.; Kleven, S.H.

    1995-01-01

    We determined the prevalence of mycoplasma infection in breeding mallard (Anas platyrhynchos) and canvasback (Aythya valisineria) hens and their broods from the central United States (1988 to 1990); and wintering American black duck (Anas rubripes) and mallard hens from the eastern United States (1990 to 1993). Mycoplasmas were isolated by culturing tracheal swabs from 656 live birds and tissue samples from 112 dead waterfowl. Nine (18%) of 51 mycoplasma isolates were identified as Mycoplasma anatis; M. anatis was recovered from four mallards, a black duck, and a gadwall (Anas strepera) duckling. Nineteen (37%) of 51 mycoplasma isolates were identified as Mycoplasma cloacale; these isolates were obtained from mallard, canvasback, and black duck adults, and from a mallard duckling. Additional unspeciated mycoplasmas were isolated from mallards, black ducks, and one canvasback.

  12. Substrate induced gliding for a nematic liquid crystal layer

    NASA Astrophysics Data System (ADS)

    Mema, Ensela; Cummings, Linda; Kondic, Lou

    2015-03-01

    The interaction between nematic liquid crystals (NLC) and polymer substrates is of current industrial interest, due to a desire to manufacture a new generation of flexible Liquid Crystal Displays (LCDs) for use in portable electronic devices. Polymer substrates present challenges because they can interact with the NLC, exhibiting a phenomenon known as gliding: the preferred orientation of the NLC molecules at the interface changes over timescales of minutes to hours. We present two models for gliding, inspired by the physics and chemistry of the interaction between the NLC and polymer substrate. These models, though simple, lead to non-trivial results, including loss of bistability, a finding that may have implications for display devices. Supported by NSF Grant No. DMS-1211713.

  13. Investigation of Aerodynamic Capabilities of Flying Fish in Gliding Flight

    NASA Astrophysics Data System (ADS)

    Park, H.; Choi, H.

    In the present study, we experimentally investigate the aerodynamic capabilities of flying fish. We consider four different flying fish models, which are darkedged-wing flying fishes stuffed in actual gliding posture. Some morphological parameters of flying fish such as lateral dihedral angle of pectoral fins, incidence angles of pectoral and pelvic fins are considered to examine their effect on the aerodynamic performance. We directly measure the aerodynamic properties (lift, drag, and pitching moment) for different morphological parameters of flying fish models. For the present flying fish models, the maximum lift coefficient and lift-to-drag ratio are similar to those of medium-sized birds such as the vulture, nighthawk and petrel. The pectoral fins are found to enhance the lift-to-drag ratio and the longitudinal static stability of gliding flight. On the other hand, the lift coefficient and lift-to-drag ratio decrease with increasing lateral dihedral angle of pectoral fins.

  14. [Hofmannsthal and the gliding out of this world].

    PubMed

    Tellenbach, H

    1988-01-01

    In the sphere of language, Hugo von Hofmannsthal was already in his childhood talented by nature. His first poems and essays he wrote when he was 17 years old, his first drama ("The Death of Tizian") in his 18th year. From the beginning he followed the great tradition of the theatre of Vienna. His lyrical creations end already before he turned 30 years. At this time the dramatist begins with the reception of the medieval mystery plays, Calderon and the greek-oriental myths. The phenomena of gliding-out-of-the-world are found before this time, in the period of his very own spiritual conceiving. They show a remarkable inclination to abandon the world of reality (Wirklichkeit, koinos kosmos): gliding into the world of dream and trance, of phantastic tales, of magic and demonia, of depersonalization and dilusion, of dying and of death (idios kosmos). These tendencies vanish when Hofmannsthal turns to more conventional topics. PMID:3073605

  15. Dialysis Culture of T-Strain Mycoplasmas

    PubMed Central

    Masover, Gerald K.; Hayflick, Leonard

    1974-01-01

    Using dialyzing cultures of T-strain mycoplasmas, it was possible to make some observations relevant to the growth and metabolism of these organisms which would not be possible in nondialyzing cultures due to growth inhibition of the organisms by elevated pH and increased ammonium ion concentration in media containing urea. The rate of ammonia accumulation was found to be related to the initial urea concentration in the medium and could not be accounted for by any change in the multiplication rate of the organisms. More ammonia was generated than could be accounted for by the added urea alone, suggesting that an ammonia-producing activity other than urease may be present in T-strain mycoplasmas. Titers above 107 color change units per ml were achieved in dialysis cultures of a T-strain mycoplasma in the presence of urea, and such titers were maintained for approximately 60 h during dialysis culture in the absence of added urea. PMID:4595203

  16. Crystal geometry of screw dislocation glide in tungsten nanocrystals

    NASA Astrophysics Data System (ADS)

    Sadanov, E. V.

    2015-02-01

    A zigzag pattern of low-temperature dislocation glide occurring in tungsten nanocrystals in the intersecting planes {110} and {211}, which belong to the <111> crystallographic zone, has been revealed using field ion microscopy. It has been shown that cores of 1/2[111] screw dislocations are undissociated within the limits of the resolution of the field ion microscope. It has been found experimentally that surface atoms are displaced into metastable positions in the region of the trace of screw dislocation motion.

  17. Soil erosion by snow gliding - a first quantification attempt in a subalpine area in Switzerland

    NASA Astrophysics Data System (ADS)

    Meusburger, K.; Leitinger, G.; Mabit, L.; Mueller, M. H.; Walter, A.; Alewell, C.

    2014-09-01

    Snow processes might be one important driver of soil erosion in Alpine grasslands and thus the unknown variable when erosion modelling is attempted. The aim of this study is to assess the importance of snow gliding as a soil erosion agent for four different land use/land cover types in a subalpine area in Switzerland. We used three different approaches to estimate soil erosion rates: sediment yield measurements in snow glide depositions, the fallout radionuclide 137Cs and modelling with the Revised Universal Soil Loss Equation (RUSLE). RUSLE permits the evaluation of soil loss by water erosion, the 137Cs method integrates soil loss due to all erosion agents involved, and the measurement of snow glide deposition sediment yield can be directly related to snow-glide-induced erosion. Further, cumulative snow glide distance was measured for the sites in the winter of 2009/2010 and modelled for the surrounding area and long-term average winter precipitation (1959-2010) with the spatial snow glide model (SSGM). Measured snow glide distance confirmed the presence of snow gliding and ranged from 2 to 189 cm, with lower values on the north-facing slopes. We observed a reduction of snow glide distance with increasing surface roughness of the vegetation, which is an important information with respect to conservation planning and expected and ongoing land use changes in the Alps. Snow glide erosion estimated from the snow glide depositions was highly variable with values ranging from 0.03 to 22.9 t ha-1 yr-1 in the winter of 2012/2013. For sites affected by snow glide deposition, a mean erosion rate of 8.4 t ha-1 yr-1 was found. The difference in long-term erosion rates determined with RUSLE and 137Cs confirms the constant influence of snow-glide-induced erosion, since a large difference (lower proportion of water erosion compared to total net erosion) was observed for sites with high snow glide rates and vice versa. Moreover, the difference between RUSLE and 137Cs erosion

  18. Abdominal breathing manoeuvre reduces passive drag acting on gliding swimmers.

    PubMed

    Maruyama, Yusuke; Yanai, Toshimasa

    2015-01-01

    The purpose of this study was to test the hypothesis that the passive drag acting on a gliding swimmer is reduced if the swimmer adopts an abdominal breathing manoeuvre (expanding the abdominal wall) rather than chest breathing manoeuvre (expanding the rib cage). Eleven male participants participated in this study. A specialised towing machine was used to tow each participant with tension set at various magnitudes and to record time series data of towing velocity. Participants were asked to inhale air by expanding the abdominal wall or the rib cage and to maintain the same body configuration throughout gliding. The steady-state velocity was measured and the coefficient of drag was calculated for each towing trial to compare between the breathing manoeuvres. The results showed that the towing velocity was increased by 0.02 m/s with a towing force of 34.3 N and by 0.06 m/s with a towing force of 98.1 N. The coefficient of drag was reduced by 5% with the abdominal breathing manoeuvre, which was found to be statistically significant (p < 0.05). These results indicate that adopting the abdominal breathing manoeuvre during gliding reduces the passive drag and the hypothesis was supported. PMID:26715235

  19. Characteristics of Atmospheric Pressure Rotating Gliding Arc Plasmas

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Zhu, Fengsen; Tu, Xin; Bo, Zheng; Cen, Kefa; Li, Xiaodong

    2016-05-01

    In this work, a novel direct current (DC) atmospheric pressure rotating gliding arc (RGA) plasma reactor has been developed for plasma-assisted chemical reactions. The influence of the gas composition and the gas flow rate on the arc dynamic behaviour and the formation of reactive species in the N2 and air gliding arc plasmas has been investigated by means of electrical signals, high speed photography, and optical emission spectroscopic diagnostics. Compared to conventional gliding arc reactors with knife-shaped electrodes which generally require a high flow rate (e.g., 10–20 L/min) to maintain a long arc length and reasonable plasma discharge zone, in this RGA system, a lower gas flow rate (e.g., 2 L/min) can also generate a larger effective plasma reaction zone with a longer arc length for chemical reactions. Two different motion patterns can be clearly observed in the N2 and air RGA plasmas. The time-resolved arc voltage signals show that three different arc dynamic modes, the arc restrike mode, takeover mode, and combined modes, can be clearly identified in the RGA plasmas. The occurrence of different motion and arc dynamic modes is strongly dependent on the composition of the working gas and gas flow rate. supported by National Natural Science Foundation of China (No. 51576174), the Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20120101110099) and the Fundamental Research Funds for the Central Universities (No. 2015FZA4011)

  20. Synergism between upregulation of Rab7 and inhibition of autophagic degradation caused by mycoplasma facilitates intracellular mycoplasma infection

    PubMed Central

    HU, XIAOPENG; YU, JIE; ZHOU, XIANG; LI, ZHAOMING; XIA, YUN; LUO, ZHIYONG; WU, YAQUN

    2014-01-01

    Following fusion of a mycoplasma with a host cell membrane, the inserted components of mycoplasma may then be transported through the endocytic pathway. However, the effects of mycoplasmas on the host cell endomembrane system are largely unknown. In this study, mycoplasma-induced changes in the dynamics of endocytic and autophagic systems were investigated. Endocytosis and autophagy are two major processes involved in the survival of intracellular prokaryotic pathogens. It was found that, immediately following infection, mycoplasmas induce endocytosis in the host cell; however, in the long term the mycoplasmas suppress turnover of the components of the endocytic pathway. Immunofluorescence microscopy revealed that Rab7 and LC3-II are recruited to the intracellular mycoplasma-containing compartments. Western blot analysis and quantitative reverse transcription-polymerase chain reaction (qPCR) showed that mycoplasmas increase expression of Rab7 by upregulating transcription, but increase levels of LC3-II and p62 by post-translational regulation. Furthermore, it was demonstrated that mycoplasma infection causes inhibition of autophagic degradation of LC3-II and p62. In addition, it was found that upregulation of Rab7 and inhibition of autophagic degradation synergistically contributes to intracellular mycoplasma accumulation. In conclusion, these findings suggest that mycoplasmas may manipulate host cell endosomal and autophagic systems in order to facilitate intracellular infection. PMID:24452847

  1. [Severe stomatitis caused by Mycoplasma pneumoniae infection].

    PubMed

    Barfod, T S; Pedersen, C

    1999-11-15

    Mycoplasma pneumoniae infection is sometimes followed by systemic reactions such as erythema multiforme major/Stevens-Johnsons syndrome. In the described case, a 30 year-old man developed severe inflammation of the oral mucous membranes following respiratory infection with Mycoplasma pneumoniae. There was also conjunctivitis and diarrhoea, and a target-like eruption was seen on the penis, but apart from slight perioral erythema and periorbital swelling, no further skin involvement was seen. The patient was treated with macrolide antibiotics for 14 days and gradually recovered. PMID:10611837

  2. Conditions for growing Mycoplasma canadense and Mycoplasma verecundum in a serum-free medium.

    PubMed

    Muñoz, G; Sotomayor, P

    1990-07-01

    Mycoplasma canadense and Mycoplasma verecundum were cultured in a serum-free medium containing bovine serum albumin, cholesterol, oleic acid, and palmitic acid in order to avoid the addition of horse serum. Growth was detected by measurement of A640 and by colony formation. The level of growth attained in this medium was less than that obtained in the horse serum-supplemented media, but colonies retained their distinctive morphology. PMID:2202260

  3. Conditions for growing Mycoplasma canadense and Mycoplasma verecundum in a serum-free medium.

    PubMed Central

    Muñoz, G; Sotomayor, P

    1990-01-01

    Mycoplasma canadense and Mycoplasma verecundum were cultured in a serum-free medium containing bovine serum albumin, cholesterol, oleic acid, and palmitic acid in order to avoid the addition of horse serum. Growth was detected by measurement of A640 and by colony formation. The level of growth attained in this medium was less than that obtained in the horse serum-supplemented media, but colonies retained their distinctive morphology. Images PMID:2202260

  4. A phylogenetic analysis of the mycoplasmas: basis for their classification.

    PubMed Central

    Weisburg, W G; Tully, J G; Rose, D L; Petzel, J P; Oyaizu, H; Yang, D; Mandelco, L; Sechrest, J; Lawrence, T G; Van Etten, J

    1989-01-01

    Small-subunit rRNA sequences were determined for almost 50 species of mycoplasmas and their walled relatives, providing the basis for a phylogenetic systematic analysis of these organisms. Five groups of mycoplasmas per se were recognized (provisional names are given): the hominis group (which included species such as Mycoplasma hominis, Mycoplasma lipophilum, Mycoplasma pulmonis, and Mycoplasma neurolyticum), the pneumoniae group (which included species such as Mycoplasma pneumoniae and Mycoplasma muris), the spiroplasma group (which included species such as Mycoplasma mycoides, Spiroplasma citri, and Spiroplasma apis), the anaeroplasma group (which encompassed the anaeroplasmas and acholeplasmas), and a group known to contain only the isolated species Asteroleplasma anaerobium. In addition to these five mycoplasma groups, a sixth group of variously named gram-positive, walled organisms (which included lactobacilli, clostridia, and other organisms) was also included in the overall phylogenetic unit. In each of these six primary groups, subgroups were readily recognized and defined. Although the phylogenetic units identified by rRNA comparisons are difficult to recognize on the basis of mutually exclusive phenotypic characters alone, phenotypic justification can be given a posteriori for a number of them. PMID:2592342

  5. Functional anatomy of gliding membrane muscles in the sugar glider (Petaurus breviceps).

    PubMed

    Endo, H; Yokokawa, K; Kurohmaru, M; Hayashi, Y

    1998-02-01

    In order to clarify the morphological adaptation for gliding behavior in the marsupial mammals, the gliding membrane muscles in the sugar glider (Petaurus breviceps) were observed. Unlike the styliform cartilage in flying squirrels, the sugar glider has a well-developed tibiocarpalis muscle in the most lateral area of the gliding membrane. The gliding membrane substantially consists of the humerodorsalis and tibioabdominalis muscle complex. We believe that the thick tibiocarpalis bundle and the humerodorsalis and tibioabdominalis muscle complex may serve as a membrane controller in the gliding behavior. A characteristic thin membranous structure between the cutaneous and deeper muscles was observed. In addition to the direct powerful control exerted by trunk and limb movement, we suggest that indirect power conduction by this thin membranous structure may contribute to gliding membrane control. PMID:9488912

  6. Macrolide-Resistant Mycoplasma pneumoniae, United States.

    PubMed

    Zheng, Xiaotian; Lee, Stella; Selvarangan, Rangaraj; Qin, Xuan; Tang, Yi-Wei; Stiles, Jeffrey; Hong, Tao; Todd, Kathleen; Ratliff, Amy E; Crabb, Donna M; Xiao, Li; Atkinson, T Prescott; Waites, Ken B

    2015-08-01

    Macrolide-resistant Mycoplasma pneumoniae (MRMP) is highly prevalent in Asia and is now being reported from Europe. Few data on MRMP are available in the United States. Using genotypic and phenotypic methods, we detected high-level MRMP in 13.2% of 91 M. pneumoniae--positive specimens from 6 US locations. PMID:26196107

  7. Mycoplasma Pneumoniae Infections of Adults and Children

    PubMed Central

    Cherry, James D.; Welliver, Robert C.

    1976-01-01

    Although the hallmark of Mycoplasma pneumoniae infection is pneumonia, the organism is also responsible for a protean array of other symptoms. With an increased awareness of the board clinical spectrum of M. pneumoniae disease and the ready availability of the cold agglutinin and M. pneumoniae complement-fixation tests, interested clinicians will note additional clinical-mycoplasmal associations in their patients. PMID:782043

  8. Genome Annotation of Five Mycoplasma canis Strains

    PubMed Central

    May, M.; Michaels, D. L.; Barbet, A. F.

    2012-01-01

    To understand its potential to cause invasive disease, the genome of Mycoplasma canis strain PG14T from a dog's throat was compared to those of isolates from the genital tract or brain of dogs. The average nucleotide identity between strain pairs is 98%, and their genome annotations are similar. PMID:22815452

  9. Diagnosis of genital Mycoplasma and Ureaplasma infections.

    PubMed

    Friberg, J

    1985-03-01

    Genital Mycoplasma and Ureaplasma have been implicated in pelvic inflammatory disease, puerperal infections, septic abortions, low birth weight, nongonococcal urethritis and prostatitis as well as spontaneous abortion and infertility. An unequivocal diagnosis of infection with these organisms can be made only after properly obtained specimens have been evaluated with the use of selective cultures. PMID:4020782

  10. Mycoplasma gallisepticum: Control by live attenuated vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercially available attenuated strains of Mycoplasma gallisepticum (MG) are commonly used within the layer industry to control MG-induced mycoplasmosis. Among these are two live MG vaccines derived from the moderately pathogenic MG “chick F” strain. In the present study, the commercially availa...

  11. A Compendium for Mycoplasma pneumoniae.

    PubMed

    Parrott, Gretchen L; Kinjo, Takeshi; Fujita, Jiro

    2016-01-01

    Historically, atypical pneumonia was a term used to describe an unusual presentation of pneumonia. Currently, it is used to describe the multitude of symptoms juxtaposing the classic symptoms found in cases of pneumococcal pneumonia. Specifically, atypical pneumonia is a syndrome resulting from a relatively common group of pathogens including Chlamydophila sp., and Mycoplasma pneumoniae. The incidence of M. pneumoniae pneumonia in adults is less than the burden experienced by children. Transmission rates among families indicate children may act as a reservoir and maintain contagiousness over a long period of time ranging from months to years. In adults, M. pneumoniae typically produces a mild, "walking" pneumonia and is considered to be one of the causes of persistent cough in patients. M. pneumoniae has also been shown to trigger the exacerbation of other lung diseases. It has been repeatedly detected in patients with bronchitis, asthma, chronic obstructive pulmonary disorder, and cystic fibrosis. Recent advances in technology allow for the rapid diagnosis of M. pneumoniae through the use of polymerase chain reaction or rapid antigen tests. With this, more effort has been afforded to identify the causative etiologic agent in all cases of pneumonia. However, previous practices, including the overprescribing of macrolide treatment in China and Japan, have created increased incidence of macrolide-resistant M. pneumoniae. Reports from these countries indicate that >85% of M. pneumoniae pneumonia pediatric cases are macrolide-resistant. Despite its extensively studied past, the smallest bacterial species still inspires some of the largest questions. The developments in microbiology, diagnostic features and techniques, epidemiology, treatment and vaccines, and upper respiratory conditions associated with M. pneumoniae in adult populations are included within this review. PMID:27148202

  12. DNA repair in Mycoplasma gallisepticum

    PubMed Central

    2013-01-01

    Background DNA repair is essential for the maintenance of genome stability in all living beings. Genome size as well as the repertoire and abundance of DNA repair components may vary among prokaryotic species. The bacteria of the Mollicutes class feature a small genome size, absence of a cell wall, and a parasitic lifestyle. A small number of genes make Mollicutes a good model for a “minimal cell” concept. Results In this work we studied the DNA repair system of Mycoplasma gallisepticum on genomic, transcriptional, and proteomic levels. We detected 18 out of 22 members of the DNA repair system on a protein level. We found that abundance of the respective mRNAs is less than one per cell. We studied transcriptional response of DNA repair genes of M. gallisepticum at stress conditions including heat, osmotic, peroxide stresses, tetracycline and ciprofloxacin treatment, stationary phase and heat stress in stationary phase. Conclusions Based on comparative genomic study, we determined that the DNA repair system M. gallisepticum includes a sufficient set of proteins to provide a cell with functional nucleotide and base excision repair and mismatch repair. We identified SOS-response in M. gallisepticum on ciprofloxacin, which is a known SOS-inducer, tetracycline and heat stress in the absence of established regulators. Heat stress was found to be the strongest SOS-inducer. We found that upon transition to stationary phase of culture growth transcription of DNA repair genes decreases dramatically. Heat stress does not induce SOS-response in a stationary phase. PMID:24148612

  13. Cellular Microbiology of Mycoplasma canis.

    PubMed

    Michaels, Dina L; Leibowitz, Jeffrey A; Azaiza, Mohammed T; Shil, Pollob K; Shama, Suzanne M; Kutish, Gerald F; Distelhorst, Steven L; Balish, Mitchell F; May, Meghan A; Brown, Daniel R

    2016-06-01

    Mycoplasma canis can infect many mammalian hosts but is best known as a commensal or opportunistic pathogen of dogs. The unexpected presence of M. canis in brains of dogs with idiopathic meningoencephalitis prompted new in vitro studies to help fill the void of basic knowledge about the organism's candidate virulence factors, the host responses that it elicits, and its potential roles in pathogenesis. Secretion of reactive oxygen species and sialidase varied quantitatively (P < 0.01) among strains of M. canis isolated from canine brain tissue or mucosal surfaces. All strains colonized the surface of canine MDCK epithelial and DH82 histiocyte cells and murine C8-D1A astrocytes. Transit through MDCK and DH82 cells was demonstrated by gentamicin protection assays and three-dimensional immunofluorescence imaging. Strains further varied (P < 0.01) in the extents to which they influenced the secretion of tumor necrosis factor alpha (TNF-α) and the neuroendocrine regulatory peptide endothelin-1 by DH82 cells. Inoculation with M. canis also decreased major histocompatibility complex class II (MHC-II) antigen expression by DH82 cells (P < 0.01), while secretion of gamma interferon (IFN-γ), interleukin-6 (IL-6), interleukin-10 (IL-10), and complement factor H was unaffected. The basis for differences in the responses elicited by these strains was not obvious in their genome sequences. No acute cytopathic effects on any homogeneous cell line, or consistent patterns of M. canis polyvalent antigen distribution in canine meningoencephalitis case brain tissues, were apparent. Thus, while it is not likely a primary neuropathogen, M. canis has the capacity to influence meningoencephalitis through complex interactions within the multicellular and neurochemical in vivo milieu. PMID:27045036

  14. A Compendium for Mycoplasma pneumoniae

    PubMed Central

    Parrott, Gretchen L.; Kinjo, Takeshi; Fujita, Jiro

    2016-01-01

    Historically, atypical pneumonia was a term used to describe an unusual presentation of pneumonia. Currently, it is used to describe the multitude of symptoms juxtaposing the classic symptoms found in cases of pneumococcal pneumonia. Specifically, atypical pneumonia is a syndrome resulting from a relatively common group of pathogens including Chlamydophila sp., and Mycoplasma pneumoniae. The incidence of M. pneumoniae pneumonia in adults is less than the burden experienced by children. Transmission rates among families indicate children may act as a reservoir and maintain contagiousness over a long period of time ranging from months to years. In adults, M. pneumoniae typically produces a mild, “walking” pneumonia and is considered to be one of the causes of persistent cough in patients. M. pneumoniae has also been shown to trigger the exacerbation of other lung diseases. It has been repeatedly detected in patients with bronchitis, asthma, chronic obstructive pulmonary disorder, and cystic fibrosis. Recent advances in technology allow for the rapid diagnosis of M. pneumoniae through the use of polymerase chain reaction or rapid antigen tests. With this, more effort has been afforded to identify the causative etiologic agent in all cases of pneumonia. However, previous practices, including the overprescribing of macrolide treatment in China and Japan, have created increased incidence of macrolide-resistant M. pneumoniae. Reports from these countries indicate that >85% of M. pneumoniae pneumonia pediatric cases are macrolide-resistant. Despite its extensively studied past, the smallest bacterial species still inspires some of the largest questions. The developments in microbiology, diagnostic features and techniques, epidemiology, treatment and vaccines, and upper respiratory conditions associated with M. pneumoniae in adult populations are included within this review. PMID:27148202

  15. Antimicrobial susceptibilities of Mycoplasma isolated from bovine mastitis in Japan.

    PubMed

    Kawai, Kazuhiro; Higuchi, Hidetoshi; Iwano, Hidetomo; Iwakuma, Akihiro; Onda, Ken; Sato, Reiichiro; Hayashi, Tomohito; Nagahata, Hajime; Oshida, Toshio

    2014-01-01

    Mycoplasma spp. are highly contagious pathogens and intramammary Mycoplasma infection is a serious issue for the dairy industry. As there is no effective vaccine for Mycoplasma infection, control depends on good husbandry and chemo-antibiotic therapy. In this study, antimicrobial susceptibility of Mycoplasma strains recently isolated from cases of bovine mastitis in Japan was evaluated by minimum inhibitory concentration (MIC). All Mycoplasma bovis strains were sensitive to pirlimycin, danofloxacin and enrofloxacin, but not kanamycin, oxytetracycline, tilmicosin or tylosin. M. californicum and M. bovigenitalium strains were sensitive to pirlimycin, danofloxacin, enrofloxacin, oxytetracycline, tilmicosin and tylosin, but not to kanamycin. This is the first report to describe the MIC of major antimicrobial agents for Mycoplasma species isolated from bovine mastitis in Japan. PMID:24261609

  16. Radiation enhanced basal plane dislocation glide in GaN

    NASA Astrophysics Data System (ADS)

    Yakimov, Eugene B.; Vergeles, Pavel S.; Polyakov, Alexander Y.; Lee, In-Hwan; Pearton, Stephen J.

    2016-05-01

    A movement of basal plane segments of dislocations in GaN films grown by epitaxial lateral overgrowth under low energy electron beam irradiation (LEEBI) was studied by the electron beam induced current (EBIC) method. Only a small fraction of the basal plane dislocation segments were susceptible to irradiation and the movement was limited to relatively short distances. The effect is explained by the radiation enhanced dislocation glide (REDG) in the structure with strong pinning. A dislocation velocity under LEEBI with a beam current lower than 1 nA was estimated as about 10 nm/s. The results assuming the REDG for prismatic plane dislocations were presented.

  17. Aerodynamic characteristics of flying fish in gliding flight.

    PubMed

    Park, Hyungmin; Choi, Haecheon

    2010-10-01

    The flying fish (family Exocoetidae) is an exceptional marine flying vertebrate, utilizing the advantages of moving in two different media, i.e. swimming in water and flying in air. Despite some physical limitations by moving in both water and air, the flying fish has evolved to have good aerodynamic designs (such as the hypertrophied fins and cylindrical body with a ventrally flattened surface) for proficient gliding flight. Hence, the morphological and behavioral adaptations of flying fish to aerial locomotion have attracted great interest from various fields including biology and aerodynamics. Several aspects of the flight of flying fish have been determined or conjectured from previous field observations and measurements of morphometric parameters. However, the detailed measurement of wing performance associated with its morphometry for identifying the characteristics of flight in flying fish has not been performed yet. Therefore, in the present study, we directly measure the aerodynamic forces and moment on darkedged-wing flying fish (Cypselurus hiraii) models and correlated them with morphological characteristics of wing (fin). The model configurations considered are: (1) both the pectoral and pelvic fins spread out, (2) only the pectoral fins spread with the pelvic fins folded, and (3) both fins folded. The role of the pelvic fins was found to increase the lift force and lift-to-drag ratio, which is confirmed by the jet-like flow structure existing between the pectoral and pelvic fins. With both the pectoral and pelvic fins spread, the longitudinal static stability is also more enhanced than that with the pelvic fins folded. For cases 1 and 2, the lift-to-drag ratio was maximum at attack angles of around 0 deg, where the attack angle is the angle between the longitudinal body axis and the flying direction. The lift coefficient is largest at attack angles around 30∼35 deg, at which the flying fish is observed to emerge from the sea surface. From glide polar

  18. Isolation of mycoplasmas from a buzzard, falcons and vultures.

    PubMed

    Poveda, J B; Giebel, J; Kirchhoff, H; Fernandez, A

    1990-10-01

    Thirteen mycoplasmas were isolated from a peregrine falcon (Falco peregrinus), two saker falcons (Falco cherrug), a buzzard (Buteo buteo), a black vulture (Aegypius monachus), and two griffon vultures (Gypsfuhus). Six of them could be identified: Mycoplasma gallinarum (three isolates), M. columborale (two isolates) and M. anatis (one isolate). The remaining seven isolates did not react with antisera against the known avian mycoplasma species in the indirect immunofluorescence and growth inhibition tests. They may represent new species. PMID:18679987

  19. Synthesis of Saturated Long Chain Fatty Acids from Sodium Acetate-1-C14 by Mycoplasma1

    PubMed Central

    Pollack, J. D.; Tourtellotte, M. E.

    1967-01-01

    Three strains of Mycoplasma, M. laidlawii A and B, and Mycoplasma sp. A60549, were grown in broth containing sodium acetate-1-C14. The methyl esters of the phospholipid fatty acids of harvested radioactive cells were prepared and identified by comparison of their mobilities to known radioactive fatty acid methyl esters by use of a modified reversed-phase partition-thin layer chromatographic technique. No radioactive methyl oleate or methyl linoleate was detected. Compounds migrating as radioactive methyl myristate, stearate, palmitate, and, with less certainty, laurate and octanoate were detected. The qualitative findings for all three organisms appeared similar. M. laidlawii B synthesized a radioactive substance, presumably a saturated fatty acid detected as the methyl ester derivative, which migrated in a position intermediate to methyl myristate-1-C14 and methyl palmitate-1-C14. This work indicates that M. laidlawii A and B and Mycoplasma sp. A60549 are capable, in a complex medium containing fatty acids, of synthesizing saturated but not unsaturated fatty acids entirely or in part from acetate. Images PMID:6020566

  20. Leucyl-tRNA synthetase editing domain functions as a molecular rheostat to control codon ambiguity in Mycoplasma pathogens

    PubMed Central

    Li, Li; Palencia, Andrés; Lukk, Tiit; Li, Zhi; Luthey-Schulten, Zaida A.; Cusack, Stephen; Martinis, Susan A.; Boniecki, Michal T.

    2013-01-01

    Mycoplasma leucyl-tRNA synthetases (LeuRSs) have been identified in which the connective polypeptide 1 (CP1) amino acid editing domain that clears mischarged tRNAs are missing (Mycoplasma mobile) or highly degenerate (Mycoplasma synoviae). Thus, these enzymes rely on a clearance pathway called pretransfer editing, which hydrolyzes misactivated aminoacyl-adenylate intermediate via a nebulous mechanism that has been controversial for decades. Even as the sole fidelity pathway for clearing amino acid selection errors in the pathogenic M. mobile, pretransfer editing is not robust enough to completely block mischarging of tRNALeu, resulting in codon ambiguity and statistical proteins. A high-resolution X-ray crystal structure shows that M. mobile LeuRS structurally overlaps with other LeuRS cores. However, when CP1 domains from different aminoacyl-tRNA synthetases and origins were fused to this common LeuRS core, surprisingly, pretransfer editing was enhanced. It is hypothesized that the CP1 domain evolved as a molecular rheostat to balance multiple functions. These include distal control of specificity and enzyme activity in the ancient canonical core, as well as providing a separate hydrolytic active site for clearing mischarged tRNA. PMID:23431144

  1. Gliding arc in tornado using a reverse vortex flow

    SciTech Connect

    Kalra, Chiranjeev S.; Cho, Young I.; Gutsol, Alexander; Fridman, Alexander; Rufael, Tecle S.

    2005-02-01

    The present article reports a new gliding arc (GA) system using a reverse vortex flow ('tornado') in a cylindrical reactor (gliding arc in tornado, or GAT), as used to preserve the main advantages of traditional GA systems and overcome their main drawbacks. The primary advantages of traditional GA systems retained in the present GAT are the possibility to generate transitional plasma and to avoid considerable electrode erosion. In contrast to a traditional GA, the new GAT system ensures much more uniform gas treatment and has a significantly larger gas residence time in the reactor. The present article also describes the design of the new reactor and its stable operation regime when the variation of GAT current is very small. These features are understood to be very important for most viable applications. Additionally the GAT provides near-perfect thermal insulation from the reactor wall, indicating that the present GAT does not require the reactor wall to be constructed of high-temperature materials. The new GAT system, with its unique properties such as a high level of nonequilibrium and a large residence time, looks very promising for many industrial applications including fuel conversion, carbon dioxide conversion to carbon monoxide and oxygen, surface treatment, waste treatment, flame stabilization, hydrogen sulfide treatment, etc.

  2. Block glides offshore Newport Beach, Southern California continental margin

    SciTech Connect

    Greene, H.G.; Clarke, S.H. Jr.; Kennedy, M.P.

    1988-01-01

    The continental slope offshore Newport Beach, California, is characterized by a relatively gentle (approximately 1/sup 0/) grade and is dissected by numerous channels and canyons, of which the most conspicuous is Newport Canyon. An unusual series of block-glide landslides have developed on this lope adjacent to many of these channels. Locally, secondary channels that develop along pull-apart fractures between the slide blocks may service as conduits for downslope sediment movement. A detailed seismic-reflection survey of the area shows that the slope is underlain by soft water-saturated unstable sediment of Quaternary age. The block-glides lie wholly within this sediment; displaced blocks appear to have moved only a short distance downslope and are preserved as intact masses that exhibit downward increasing internal deformation. This deformation reaches a maximum near the front of the displaced mass and in basal beds nearest the slip surface. The morphology of the blocks and their intervening channellike erosional scarps is similar to that of glacial blocks and their associated bergschrunds. The formation of new scarps and the widening of channels formed as pull-aparts by the ongoing process of block movement may contribute to headward erosion and widening of Newport Canyon and its tributaries. Slope failure might be greatly enhanced by strong ground motion associated with nearby earthquakes. The authors suspect that renewed movement occurs on these blocks during major seismic events on the nearby Newport-Inglewood fault (e.g., 1933 M/sub L/ 6.3 event).

  3. 14 CFR 29.71 - Helicopter angle of glide: Category B.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Helicopter angle of glide: Category B. 29... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.71 Helicopter angle of glide: Category B. For each category B helicopter, except multiengine helicopters meeting...

  4. 14 CFR 29.71 - Helicopter angle of glide: Category B.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Helicopter angle of glide: Category B. 29... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.71 Helicopter angle of glide: Category B. For each category B helicopter, except multiengine helicopters meeting...

  5. Effortful Pitch Glide: A Potential New Exercise Evaluated by Dynamic MRI

    ERIC Educational Resources Information Center

    Miloro, Keri Vasquez; Pearson, William G., Jr.; Langmore, Susan E.

    2014-01-01

    Purpose: The purpose of this study was to compare the biomechanics of the effortful pitch glide (EPG) with swallowing using dynamic MRI. The EPG is a combination of a pitch glide and a pharyngeal squeeze maneuver for targeting laryngeal and pharyngeal muscles. The authors hypothesized that the EPG would elicit significantly greater structural…

  6. High Order Large Eddy Simulation (LES) of Gliding Snake Aerodynamics: Effect of 3D Flow on Gliding Performance

    NASA Astrophysics Data System (ADS)

    Delorme, Yann; Hassan, Syed Harris; Socha, Jake; Vlachos, Pavlos; Frankel, Steven

    2014-11-01

    Chrysopelea paradisi are snakes that are able to glide over long distances by morphing the cross section of their bodies from circular to a triangular airfoil, and undulating through the air. Snake glide is characterized by relatively low Reynolds number and high angle of attack as well as three dimensional and unsteady flow. Here we study the 3D dynamics of the flow using an in-house high-order large eddy simulation code. The code features a novel multi block immersed boundary method to accurately and efficiently represent the complex snake geometry. We investigate the steady state 3-dimensionality of the flow, especially the wake flow induced by the presence of the snake's body, as well as the vortex-body interaction thought to be responsible for part of the lift enhancement. Numerical predictions of global lift and drag will be compared to experimental measurements, as well as the lift distribution along the body of the snake due to cross sectional variations. Comparisons with previously published 2D results are made to highlight the importance of 3-dimensional effects. Additional efforts are made to quantify properties of the vortex shedding and Dynamic Mode Decomposition (DMD) is used to analyse the main modes responsible for the lift and drag forces.

  7. [Localization of the division protein FtsZ in mycoplasma cells Mycoplasma hominis].

    PubMed

    Vishniakov, I E; Borkhsenius, S N; Basovskiĭ, Iu I; Levitskiĭ, S A; Lazarev, V N; Snigirevskaia, E S; Komissarchik, Ia Iu

    2009-01-01

    Localization of the protein FtsZ in Mycoplasma hominis cells was determined. Ultra thin sections were treated by rabbit polyclonal antibodies against FtsZ M. hominis: a conjugate of protein A with colloidal gold particles was used instead of secondary antibodies. Considerable polymorphism of cells was seen on electron microscopy pictures of M. hominis cells, which is typical for mycoplasmas. Among a wide variety of cell shapes we distinguished dumbbell-shaped dividing cells, and the cells connected with each other with the aid of thin membrane tubules (former constrictions). Dominants distribution of the label in the constriction area of dividing M. hominis cells and in the area of the thin membrane tubules was observed. We revealed the cross septum in the mycoplasma cells for the first time, as well as the gold labeling of this structure. Furthermore, in some rounded and oval cells colloidal gold particles labeled the whole plasma membrane in ring-shaped manner. Probably, the label in these cases marks a submembrane contractile ring (Z-ring). The facts mentioned above confirm that FtsZ of M. hominis plays an active role in the mycoplasma cytokinesis. In a series of cases spiral-like distribution of gold particles was observed. Probably, FtsZ protofilaments in M. hominis cells can form spiral structures similar to Z-spirals of Bacillus subtilis and Escherichia coli. Its presence in mycoplasma cells may be considered as an important argument in favour of model of Z-ring assembling through reorganization of Z-spirals. FtsZ also may participate in maintenance of mycoplasma cell shape (membrane localization). PMID:19435279

  8. Comparative genomic and proteomic analyses of two Mycoplasma agalactiae strains: clues to the macro- and micro-events that are shaping mycoplasma diversity

    PubMed Central

    2010-01-01

    Background While the genomic era is accumulating a tremendous amount of data, the question of how genomics can describe a bacterial species remains to be fully addressed. The recent sequencing of the genome of the Mycoplasma agalactiae type strain has challenged our general view on mycoplasmas by suggesting that these simple bacteria are able to exchange significant amount of genetic material via horizontal gene transfer. Yet, events that are shaping mycoplasma genomes and that are underlining diversity within this species have to be fully evaluated. For this purpose, we compared two strains that are representative of the genetic spectrum encountered in this species: the type strain PG2 which genome is already available and a field strain, 5632, which was fully sequenced and annotated in this study. Results The two genomes differ by ca. 130 kbp with that of 5632 being the largest (1006 kbp). The make up of this additional genetic material mainly corresponds (i) to mobile genetic elements and (ii) to expanded repertoire of gene families that encode putative surface proteins and display features of highly-variable systems. More specifically, three entire copies of a previously described integrative conjugative element are found in 5632 that accounts for ca. 80 kbp. Other mobile genetic elements, found in 5632 but not in PG2, are the more classical insertion sequences which are related to those found in two other ruminant pathogens, M. bovis and M. mycoides subsp. mycoides SC. In 5632, repertoires of gene families encoding surface proteins are larger due to gene duplication. Comparative proteomic analyses of the two strains indicate that the additional coding capacity of 5632 affects the overall architecture of the surface and suggests the occurrence of new phase variable systems based on single nucleotide polymorphisms. Conclusion Overall, comparative analyses of two M. agalactiae strains revealed a very dynamic genome which structure has been shaped by gene flow

  9. Development of Mycoplasma hyopneumoniae Recombinant Vaccines.

    PubMed

    Marchioro, Silvana Beutinger; Simionatto, Simone; Dellagostin, Odir

    2016-01-01

    Mycoplasma hyopneumoniae is the etiological agent of swine enzootic pneumonia (EP), a disease that affects swine production worldwide. Vaccination is the most cost-effective strategy for the control and prevention of the disease. Research using genome-based approach has the potential to elucidate the biology and pathogenesis of M. hyopneumoniae and contribute to the development of more effective vaccines. Here, we describe the protocol for developing M. hyopneumoniae recombinant vaccines using reverse vaccinology approaches. PMID:27076288

  10. An epornitic of Mycoplasma gallisepticum in turkeys.

    PubMed

    Mason, S J; Maiers, J D

    1984-01-01

    A major epornitic of Mycoplasma gallisepticum occurred in the Monroe, North Carolina, area between January and June of 1983. The outbreak involved 304,000 turkeys of various ages, which were slaughtered in the eradication program at a cost of more than $550,000 to growers and poultry companies. An infected peafowl was the likely source of infection on the first farm. Traffic between farms by growers and company personnel was theorized to be the means of further spread. PMID:6487195

  11. Natural glide slab avalanches, Glacier National Park, USA: A unique hazard and forecasting challenge

    USGS Publications Warehouse

    Reardon, Blase; Fagre, Daniel B.; Dundas, Mark; Lundy, Chris

    2006-01-01

    In a museum of avalanche phenomena, glide cracks and glide avalanches might be housed in the “strange but true” section. These oddities are uncommon in most snow climates and tend to be isolated to specific terrain features such as bedrock slabs. Many glide cracks never result in avalanches, and when they do, the wide range of time between crack formation and slab failure makes them highly unpredictable. Despite their relative rarity, glide cracks and glide avalanches pose a regular threat and complex forecasting challenge during the annual spring opening of the Going-to-the-Sun Road in Glacier National Park, U.S.A. During the 2006 season, a series of unusual glide cracks delayed snow removal operations by over a week and provided a unique opportunity to record detailed observations of glide avalanches and characterize their occurrence and associated weather conditions. Field observations were from snowpits, crown profiles and where possible, measurements of slab thickness, bed surface slope angle, substrate and other physical characteristics. Weather data were recorded at one SNOTEL site and two automated stations located from 0.6-10 km of observed glide slab avalanches. Nearly half (43%) of the 35 glide slab avalanches recorded were Class D2-2.5, with 15% Class D3-D3.5. The time between glide crack opening and failure ranged from 2 days to over six weeks, and the avalanches occurred in cycles associated with loss of snow water equivalent and spikes in temperature and radiation. We conclude with suggest ions for further study.

  12. Gliding Motility and Por Secretion System Genes Are Widespread among Members of the Phylum Bacteroidetes

    PubMed Central

    Zhu, Yongtao

    2013-01-01

    The phylum Bacteroidetes is large and diverse, with rapid gliding motility and the ability to digest macromolecules associated with many genera and species. Recently, a novel protein secretion system, the Por secretion system (PorSS), was identified in two members of the phylum, the gliding bacterium Flavobacterium johnsoniae and the nonmotile oral pathogen Porphyromonas gingivalis. The components of the PorSS are not similar in sequence to those of other well-studied bacterial secretion systems. The F. johnsoniae PorSS genes are a subset of the gliding motility genes, suggesting a role for the secretion system in motility. The F. johnsoniae PorSS is needed for assembly of the gliding motility apparatus and for secretion of a chitinase, and the P. gingivalis PorSS is involved in secretion of gingipain protease virulence factors. Comparative analysis of 37 genomes of members of the phylum Bacteroidetes revealed the widespread occurrence of gliding motility genes and PorSS genes. Genes associated with other bacterial protein secretion systems were less common. The results suggest that gliding motility is more common than previously reported. Microscopic observations confirmed that organisms previously described as nonmotile, including Croceibacter atlanticus, “Gramella forsetii,” Paludibacter propionicigenes, Riemerella anatipestifer, and Robiginitalea biformata, exhibit gliding motility. Three genes (gldA, gldF, and gldG) that encode an apparent ATP-binding cassette transporter required for F. johnsoniae gliding were absent from two related gliding bacteria, suggesting that the transporter may not be central to gliding motility. PMID:23123910

  13. Mycoplasmas and cancer: focus on nucleoside metabolism

    PubMed Central

    Vande Voorde, Johan; Balzarini, Jan; Liekens, Sandra

    2014-01-01

    The standard of care for patients suffering cancer often includes treatment with nucleoside analogues (NAs). NAs are internalized by cell-specific nucleobase/nucleoside transporters and, after enzymatic activation (often one or more phosphorylation steps), interfere with cellular nucleo(s)(t)ide metabolism and DNA/RNA synthesis. Therefore, their efficacy is highly dependent on the expression and activity of nucleo(s)(t)ide-metabolizing enzymes, and alterations thereof (e.g. by down/upregulated expression or mutations) may change the susceptibility to NA-based therapy and/or confer drug resistance. Apart from host cell factors, several other variables including microbial presence may determine the metabolome (i.e. metabolite concentrations) of human tissues. Studying the diversity of microorganisms that are associated with the human body has already provided new insights in several diseases (e.g. diabetes and inflammatory bowel disease) and the metabolic exchange between tissues and their specific microbiota was found to affect the bioavailability and toxicity of certain anticancer drugs, including NAs. Several studies report a preferential colonization of tumor tissues with some mycoplasma species (mostly Mycoplasma hyorhinis). These prokaryotes are also a common source of cell culture contamination and alter the cytostatic activity of some NAs in vitro due to the expression of nucleoside-catabolizing enzymes. Mycoplasma infection may therefore bias experimental work with NAs, and their presence in the tumor microenvironment could be of significance when optimizing nucleoside-based cancer treatment. PMID:26417262

  14. Dialysis culture of T-strain mycoplasmas.

    PubMed

    Masover, G K; Hayflick, L

    1974-04-01

    Using dialyzing cultures of T-strain mycoplasmas, it was possible to make some observations relevant to the growth and metabolism of these organisms which would not be possible in nondialyzing cultures due to growth inhibition of the organisms by elevated pH and increased ammonium ion concentration in media containing urea. The rate of ammonia accumulation was found to be related to the initial urea concentration in the medium and could not be accounted for by any change in the multiplication rate of the organisms. More ammonia was generated than could be accounted for by the added urea alone, suggesting that an ammonia-producing activity other than urease may be present in T-strain mycoplasmas. Titers above 10(7) color change units per ml were achieved in dialysis cultures of a T-strain mycoplasma in the presence of urea, and such titers were maintained for approximately 60 h during dialysis culture in the absence of added urea. PMID:4595203

  15. Mycoplasma hominis, a Rare but True Cause of Infective Endocarditis

    PubMed Central

    Grattard, Florence; Morel, Jerome; Suy, Florence; Fuzellier, Jean-François; Verhoeven, Paul; Cazorla, Celine; Guglielminotti, Claire; Fresard, Anne; Lucht, Frederic; Botelho-Nevers, Elisabeth

    2015-01-01

    Mycoplasma spp. are rarely recognized agents of infective endocarditis. We report a case of Mycoplasma hominis prosthetic valve endocarditis diagnosed by 16S ribosomal DNA (rDNA) PCR and culture of valves in a 74-year-old man. We reviewed the literature and found only 8 other cases reported. PMID:26135868

  16. Soil erosion by snow gliding - a first quantification attempt in a sub-alpine area, Switzerland

    NASA Astrophysics Data System (ADS)

    Meusburger, K.; Leitinger, G.; Mabit, L.; Mueller, M. H.; Walter, A.; Alewell, C.

    2014-03-01

    Snow processes might be one important driver of soil erosion in Alpine grasslands and thus the unknown variable when erosion modelling is attempted. The aim of this study is to assess the importance of snow gliding as soil erosion agent for four different land use/land cover types in a sub-alpine area in Switzerland. We used three different approaches to estimate soil erosion rates: sediment yield measurements in snow glide deposits, the fallout radionuclide 137Cs, and modelling with the Revised Universal Soil Loss Equation (RUSLE). The RUSLE model is suitable to estimate soil loss by water erosion, while the 137Cs method integrates soil loss due to all erosion agents involved. Thus, we hypothesise that the soil erosion rates determined with the 137Cs method are higher and that the observed discrepancy between the soil erosion rate of RUSLE and the 137Cs method is related to snow gliding and sediment concentrations in the snow glide deposits. Cumulative snow glide distance was measured for the sites in the winter 2009/10 and modelled for the surrounding area with the Spatial Snow Glide Model (SSGM). Measured snow glide distance ranged from 2 to 189 cm, with lower values at the north facing slopes. We observed a reduction of snow glide distance with increasing surface roughness of the vegetation, which is important information with respect to conservation planning and expected land use changes in the Alps. Our hypothesis was confirmed: the difference of RUSLE and 137Cs erosion rates was related to the measured snow glide distance (R2= 0.64; p < 0.005) and snow sediment yields (R2 = 0.39; p = 0.13). A high difference (lower proportion of water erosion compared to total net erosion) was observed for high snow glide rates and vice versa. The SSGM reproduced the relative difference of the measured snow glide values under different land uses and land cover types. The resulting map highlighted the relevance of snow gliding for large parts of the investigated area. Based

  17. GlideScope and Frova Introducer for Difficult Airway Management

    PubMed Central

    Ciccozzi, Alessandra; Guetti, Cristiana; Papola, Roberta; Paladini, Antonella; Varrassi, Giustino; Marinangeli, Franco

    2013-01-01

    The introduction into clinical practice of new tools for intubation as videolaringoscopia has dramatically improved the success rate of intubation and the work of anesthesiologists in what is considered the most delicate maneuver. Nevertheless intubation difficulties may also be encountered with good anatomical visualization of glottic structures in videolaringoscopia. To overcome the obstacles that may occur both in a difficult provided intubation such as those unexpected, associated endotracheal introducer able to facilitate the passage of the endotracheal tube through the vocal cords into the trachea may be useful. We report 4 cases of difficult intubation planned and unplanned and completed successfully using the GlideScope videolaryngoscope associated with endotracheal Frova introducer. PMID:23991339

  18. Degradation of tetrafluoroethane using three-phase gliding arc plasma

    NASA Astrophysics Data System (ADS)

    Pacheco, J.; García, M.; Pacheco, M.; Valdivia, R.; Rivera, C.; Garduño, M.

    2012-06-01

    The use of many chlorofluorocarbons (CFC's) has negatively impacted the ozone layer. The Montreal Protocol was implemented, as a temporary solution for this problem by replacing CFC's by hydrofluorocarbons (HFC's). These kinds of gases have the propriety to be free of chlorine. However, in a next future, the Montreal Protocol also considers the replacement of HFC's because they have a high global warming potential when they enter in contact with the atmosphere. One of the methods to remove those compounds is the gliding arc plasma because it presents some advantages. The inlet system works near the atmospheric pressure and has a transition region from plasma at thermodynamic local partial equilibrium to non-thermal plasma; allowing high gas and electronic temperatures. Results present a promissory possibility to be scaled and to give an industrial service.

  19. Leaping shampoo glides on a lubricating air layer

    NASA Astrophysics Data System (ADS)

    Lee, S.; Li, E. Q.; Marston, J. O.; Bonito, A.; Thoroddsen, S. T.

    2013-06-01

    When a stream of shampoo is fed onto a pool in one's hand, a jet can leap sideways or rebound from the liquid surface in an intriguing phenomenon known as the Kaye effect. Earlier studies have debated whether non-Newtonian effects are the underlying cause of this phenomenon, making the jet glide on top of a shear-thinning liquid layer, or whether an entrained air layer is responsible. Herein we show unambiguously that the jet slides on a lubricating air layer. We identify this layer by looking through the pool liquid and observing its rupture into fine bubbles. The resulting microbubble sizes suggest this air layer is of submicron thickness. This thickness estimate is also supported by the tangential deceleration of the jet during the rebounding.

  20. Employment of hypersonic glide vehicles: Proposed criteria for use

    SciTech Connect

    Olguin, Abel

    2014-07-01

    Hypersonic Glide Vehicles (HGVs) are a type of reentry vehicle that couples the high speed of ballistic missiles with the maneuverability of aircraft. The HGV has been in development since the 1970s, and its technology falls under the category of Conventional Prompt Global Strike (CPGS) weapons. As noted by James M. Acton, a senior associate in the Nuclear Policy Program at the Carnegie Endowment, CPGS is a “missile in search of a mission.” With the introduction of any significant new military capability, a doctrine for use—including specifics regarding how, when and where it would be used, as well as tactics, training and procedures—must be clearly defined and understood by policy makers, military commanders, and planners. In this paper, benefits and limitations of the HGV are presented. Proposed criteria and four scenarios illustrate a possible method for assessing when to use an HGV.

  1. Glide planes symmetry in the organization of some sulfide structures

    NASA Astrophysics Data System (ADS)

    Borisov, S. V.; Magarill, S. A.; Pervukhina, N. V.

    2016-03-01

    The role of glide planes in the organization of structures is shown based on a crystallographic analysis of the monoclinic structures of TlAs3S5 and Tl2(As,Sb)3S13 sulfides. In the first structure, cations and anions form systems (with identical geometries) of two face-centered sublattices, linked by the c plane, with the effect of unified "two-dimensional" (2D) ordering. The second structure, exhibiting signs of order-disorder (OD) type, is interpreted as a superposition of two noncentrosymmetric components with independent cation and anion sublattices, which, however, also form a regular 2D order due to the n plane. The stabilizing role of Tl cations in the geometry of cation matrices is indicated.

  2. Collective behavior of minus-ended motors in mitotic microtubule asters gliding toward DNA

    NASA Astrophysics Data System (ADS)

    Athale, Chaitanya A.; Dinarina, Ana; Nedelec, Francois; Karsenti, Eric

    2014-02-01

    Microtubules (MTs) nucleated by centrosomes form star-shaped structures referred to as asters. Aster motility and dynamics is vital for genome stability, cell division, polarization and differentiation. Asters move either toward the cell center or away from it. Here, we focus on the centering mechanism in a membrane independent system of Xenopus cytoplasmic egg extracts. Using live microscopy and single particle tracking, we find that asters move toward chromatinized DNA structures. The velocity and directionality profiles suggest a random-walk with drift directed toward DNA. We have developed a theoretical model that can explain this movement as a result of a gradient of MT length dynamics and MT gliding on immobilized dynein motors. In simulations, the antagonistic action of the motor species on the radial array of MTs leads to a tug-of-war purely due to geometric considerations and aster motility resembles a directed random-walk. Additionally, our model predicts that aster velocities do not change greatly with varying initial distance from DNA. The movement of asymmetric asters becomes increasingly super-diffusive with increasing motor density, but for symmetric asters it becomes less super-diffusive. The transition of symmetric asters from superdiffusive to diffusive mobility is the result of number fluctuations in bound motors in the tug-of-war. Overall, our model is in good agreement with experimental data in Xenopus cytoplasmic extracts and predicts novel features of the collective effects of motor-MT interactions.

  3. Collective behavior of minus-ended motors in mitotic microtubule asters gliding toward DNA.

    PubMed

    Athale, Chaitanya A; Dinarina, Ana; Nedelec, Francois; Karsenti, Eric

    2014-02-01

    Microtubules (MTs) nucleated by centrosomes form star-shaped structures referred to as asters. Aster motility and dynamics is vital for genome stability, cell division, polarization and differentiation. Asters move either toward the cell center or away from it. Here, we focus on the centering mechanism in a membrane independent system of Xenopus cytoplasmic egg extracts. Using live microscopy and single particle tracking, we find that asters move toward chromatinized DNA structures. The velocity and directionality profiles suggest a random-walk with drift directed toward DNA. We have developed a theoretical model that can explain this movement as a result of a gradient of MT length dynamics and MT gliding on immobilized dynein motors. In simulations, the antagonistic action of the motor species on the radial array of MTs leads to a tug-of-war purely due to geometric considerations and aster motility resembles a directed random-walk. Additionally, our model predicts that aster velocities do not change greatly with varying initial distance from DNA. The movement of asymmetric asters becomes increasingly super-diffusive with increasing motor density, but for symmetric asters it becomes less super-diffusive. The transition of symmetric asters from superdiffusive to diffusive mobility is the result of number fluctuations in bound motors in the tug-of-war. Overall, our model is in good agreement with experimental data in Xenopus cytoplasmic extracts and predicts novel features of the collective effects of motor-MT interactions. PMID:24476749

  4. Flavobacterium tistrianum sp. nov., a gliding bacterium isolated from soil.

    PubMed

    Suwannachart, Chatrudee; Rueangyotchanthana, Kanjana; Srichuay, Suksan; Pheng, Sophea; Fungsin, Bundit; Phoonsiri, Chantara; Kim, Song-Gun

    2016-06-01

    A novel gliding bacterial strain, GB 56.1T, was obtained from soil at the Sakaerat Biosphere Reserve, in Nakhon Ratchasima province, Thailand; the strain was characterized using a polyphasic approach. Cells were Gram-stain-negative, yellow, rod shaped and devoid of flagella, but showed gliding motility. Phylogenetic analysis based on 16S rRNA gene sequences found that GB 56.1T was a member of the genus Flavobacterium and that the strain shared the highest sequence similarities with Flavobacterium nitrogenifigens (98.4 %), Flavobacterium anhuiense(98.3 %) and Flavobacterium ginsenosidimutans (97.9 %). The similarities of the sequences of all other species of the genus Flavobacterium were below 97.4 %. The major respiratory quinone of strain GB 56.1T was MK-6; fatty acids were iso-C15:0, C16:1ω6c/C16:1ω7c, C16:0 and C16:0 3-OH. The major polar lipids were phosphatidylethanolamine, phosphatidylserine, an unidentified amino lipid and four polar lipids. The DNA G+C content of this strain was 34.2 mol%. The DNA-DNA relatedness of GB 56.1T was highest against F.anhuiense, with a value of 37.6 %. On the basis of morphological, physiological and chemotaxonomic characteristics, DNA-DNA hybridization relatedness and 16S rRNA gene sequence analysis, we conclude that strain GB 56.1T represents a novel species, for which the name Flavobacterium tistrianum sp. nov. is proposed. The type strain is GB 56.1T (=TISTR 1612T =KCTC 42679T). PMID:26970735

  5. Use of Real-Time PCR To Detect and Quantify Mycoplasma haemofelis and “Candidatus Mycoplasma haemominutum” DNA

    PubMed Central

    Tasker, Séverine; Helps, Chris R.; Day, Michael J.; Gruffydd-Jones, Tim J.; Harbour, Dave A.

    2003-01-01

    A real-time PCR assay using Taqman probes was developed to detect and quantify Mycoplasma haemofelis and “Candidatus Mycoplasma haemominutum” in feline blood samples. The assay was rapid and sensitive and was successfully used to monitor the in vivo kinetics of cats experimentally infected with each species. PMID:12517888

  6. Hemotropic mycoplasmas in little brown bats (Myotis lucifugus)

    PubMed Central

    2014-01-01

    Background Hemotropic mycoplasmas are epicellular erythrocytic bacteria that can cause infectious anemia in some mammalian species. Worldwide, hemotropic mycoplasmas are emerging or re-emerging zoonotic pathogens potentially causing serious and significant health problems in wildlife. The objective of this study was to determine the molecular prevalence of hemotropic Mycoplasma species in little brown bats (Myotis lucifugus) with and without Pseudogymnoascus (Geomyces) destrucans, the causative agent of white nose syndrome (WNS) that causes significant mortality events in bats. Methods In order to establish the prevalence of hemotropic Mycoplasma species in a population of 68 little brown bats (Myotis lucifugus) with (n = 53) and without (n = 15) white-nose syndrome (WNS), PCR was performed targeting the 16S rRNA gene. Results The overall prevalence of hemotropic Mycoplasmas in bats was 47%, with similar (p = 0.5725) prevalence between bats with WNS (49%) and without WNS (40%). 16S rDNA sequence analysis (~1,200 bp) supports the presence of a novel hemotropic Mycoplasma species with 91.75% sequence homology with Mycoplasma haemomuris. No differences were found in gene sequences generated from WNS and non-WNS animals. Conclusions Gene sequences generated from WNS and non-WNS animals suggest that little brown bats could serve as a natural reservoir for this potentially novel Mycoplasma species. Currently, there is minimal information about the prevalence, host-specificity, or the route of transmission of hemotropic Mycoplasma spp. among bats. Finally, the potential role of hemotropic Mycoplasma spp. as co-factors in the development of disease manifestations in bats, including WNS in Myotis lucifugus, remains to be elucidated. PMID:24655520

  7. Validation of a mycoplasma molecular diagnostic test and distribution of mycoplasma species in bovine milk among New York State dairy farms.

    PubMed

    Gioia, G; Werner, B; Nydam, D V; Moroni, P

    2016-06-01

    Mycoplasma mastitis is a contagious and costly disease of dairy cattle that significantly affects animal health and milk productivity. Mycoplasma bovis is the most prevalent and invasive agent of mycoplasma mastitis in dairy cattle, and early detection is critical. Other mycoplasma have been isolated from milk; however, the role and prevalence of these species as mastitis pathogens are poorly understood. Routine screening of milk for mycoplasma by bacteriological culture is an important component of a farm control strategy to minimize a herd mycoplasma outbreak, but phenotypic methods have limited ability to speciate mycoplasma, affecting how farms and practitioners can understand the role and effect of species other than M. bovis in herd health. Fastidious mycoplasma culture can be lengthy and inconclusive, resulting in delayed or false negative reports. We developed and validated a multitarget PCR assay that can in the same day confirm or reject a presumptive positive mycoplasma culture found upon bacteriological testing of clinical specimens, further discriminate between Acholeplasma and Mycoplasma, and identify M. bovis. Coupled with sequence analysis isolates can be further identified as bovine mycoplasma Mycoplasma arginini, Mycoplasma alkalescens, Mycoplasma canadense, Mycoplasma bovirhinis, Mycoplasma bovigenitalium, Mycoplasma californicum, Acholeplasma laidlawii, and Acholeplasma oculi. Assay validation included analysis of 845 mycoplasma representing these species and 30 additional bacterial species obtained from routine milk submissions to the Quality Milk Production Services from New York State farms and veterinary clinics between January 2012 and December 2015. Among 95 herds, we found 8 different Mycoplasma species and 3 different Acholeplasma species, with an overall prevalence of M. bovirhinis of 1%, A. oculi of 2%, M. arginini of 2%, M. californicum of 3%, M. canadense of 10%, M. bovigenitalium of 10%, A. laidlawii of 11%, M. alkalescens of 17

  8. Rare extrapulmonary complications of Mycoplasma pneumoniae infection.

    PubMed

    Dhaliwal, Kiran; Enright, Kevin

    2016-01-01

    Stevens-Johnsons syndrome (SJS) is a rare extra-pulmonary complication of Mycoplasma pneumoniae infection. We present the case of a 26-year-old man with fever, cough, extensive oral mucosal ulceration and a widespread truncal rash. He was diagnosed with M. pneumoniae-induced SJS. He responded well to antibiotics and steroids initially, but went on to develop pseudomembranous conjunctivitis requiring bilateral amniotic membrane grafting. SJS is most commonly drug-induced, however, M. pneumoniae is the commonest infectious cause and should be considered in the differential diagnosis. It is also important to get specialist care involved early to minimise the long-term effects of any complications. PMID:26837942

  9. The minimal gene complement of mycoplasma genitalium

    SciTech Connect

    Fraser, C.M.; Gocayne, J.D.; White, O.

    1995-10-20

    The complete nucleotide sequence (580,070 base pairs) of the Mycoplasma genitalium genome, the smallest known genome of any free-living organism, has been determined by whole-genome random sequencing and assembly. A total of only 470 predicted coding regions were identified that include genes required for DNA replication, transcription and translation, DNA repair, cellular transport, and energy metabolism. Comparison of this genome to that of Haemophilus influenzae suggests that differences in genome content are reflected as profound differences in physiology and metabolic capacity between these two organisms. 43 refs., 1 fig., 2 tabs.

  10. Laser radiation effects on Mycoplasma agalactiae

    NASA Astrophysics Data System (ADS)

    Dinu, Cerasela Z.; Grigoriu, Constantin; Dinescu, Maria; Pascale, Florentina; Popovici, Adrian; Gheorghescu, Lavinia; Cismileanu, Ana; Avram, Eugenia

    2002-08-01

    The biological effects of the laser radiation emitted by the Nd:YAG laser (second harmonic, wavelength 532 nm /fluence 32 mJ/cm2/pulse duration 6 ns) on the Mycoplasma agalactiae bacterium were studied. The radiation was found to intensify the multiplication of the bacteria irradiated in TRIS buffer (0.125 M), without however affecting the proteinic composition of the cell membrane. When the bacteria were irradiated in their growth medium (PPLO broth) being later cultivated on a solid medium (PPLO agar), the exclusive presence of the atypical colonies (granular and T-like ones) was noticed.

  11. Virulence, persistence and dissemination of Mycoplasma bovis.

    PubMed

    Bürki, Sibylle; Frey, Joachim; Pilo, Paola

    2015-08-31

    Bovine mycoplasmosis due to Mycoplasma bovis causes several important bovine diseases such as pneumonia, mastitis, arthritis, otitis, genital disorders or keratoconjunctivitis. Variable surface lipoproteins, adhesion, invasion of host cells, modulation of the host immune system, biofilm formation and the release of secondary metabolites like hydrogen peroxide, as well as synergistic infections with other bacterial or viral pathogens are among the more significantly studied characteristics of the bacterium. The aim of this review is to summarize the current knowledge regarding the virulence of M. bovis and additionally, factors contributing to the dissemination and persistence of this pathogen in the bovine host will be discussed. PMID:25824130

  12. [Preparation of Mycoplasma antigens and appropriate swine antisera].

    PubMed

    Berdnik, V P; Valiukh, E A; Svinorenko, N V

    1989-01-01

    An account is given in this paper of results obtained from development of methods for preparation of mycoplasma antigens and appropriate antisera from swine, as compared to normal swine sera. The exercise had been undertaken with the view to diagnosing mycoplasmosis in swine, on the basis of long-time complement fixation in microvolume. Tests were applied to 5 patterns of vaccination of swine, using antigens from mycoplasma. Benefits and drawbacks are discussed in some detail. Also described are methods for preparation, preservation, and storage of mycoplasma diagnostics which retain their suitability for the above diagnostic approach on the basis of 2-4 years of shelf life. PMID:2619459

  13. Attachment of killed Mycoplasma gallisepticum cells and membranes to erythrocytes

    SciTech Connect

    Banai, M.; Kahane, I.; Feldner, J.; Razin, S.

    1981-11-01

    To correlate viability with attachment capacity, Mycoplasma gallisepticum cells harvested at different growth phases and treated by various agents were tested for their capacity to attach to human erythrocytes. The results show that viability per se is not essential for M. gallisepticum attachment to erythrocytes, as cells killed by ultraviolet irradiation and membranes isolated by lysing M. gallisepticum cells by various means retained attachment capacity. However, treatment of the mycoplasmas by protein-denaturing agents, such as heart, glutaraldehyde, or prolonged exposure to low pH, drastically affected or even abolished attachment, supporting the protein nature of the mycoplasma membrane components responsible for specific binding to the sialoglycoprotein receptors on the erythrocytes.

  14. The role of Mycoplasma and Ureaplasma in adverse pregnancy outcomes.

    PubMed

    Murtha, Amy P; Edwards, James M

    2014-12-01

    Genital mycoplasmas are frequently found in the vaginal flora across socioeconomic and ethnic groups and have been demonstrated to be involved in adverse perinatal outcomes. Both Mycoplasma and Ureaplasma spp cause inflammation potentially leading to spontaneous preterm birth and PPROM as well as postdelivery infectious complications and neonatal infections. Herein we have provided an overview of the existing literature and supportive evidence for genital mycoplasma's role in perinatal complications. Future research will need to focus on clearly delineating the species, allowing for discrimination of their effects. PMID:25454994

  15. STS-41 Discovery, OV-103, glides over concrete runway 22 at EAFB, California

    NASA Technical Reports Server (NTRS)

    1990-01-01

    STS-41 Discovery, Orbiter Vehicle (OV) 103, with nose landing gear (NLG) and main landing gear (MLG) deployed, glides over concrete runway 22 at Edwards Air Force Base (EAFB), California, prior to touchdown.

  16. Impact of snow gliding on soil redistribution for a sub-alpine area in Switzerland

    NASA Astrophysics Data System (ADS)

    Meusburger, K.; Leitinger, G.; Mabit, L.; Mueller, M. H.; Alewell, C.

    2013-07-01

    The aim of this study is to assess the importance of snow gliding as soil erosion agent for four different land use/land cover types in a sub-alpine area in Switzerland. The 14 investigated sites are located close to the valley bottom at approximately 1500 m a.s.l., while the elevation of the surrounding mountain ranges is about 2500 m a.s.l. We used two different approaches to estimate soil erosion rates: the fallout radionuclide 137Cs and the Revised Universal Soil Loss Equation (RUSLE). The RUSLE model is suitable to estimate soil loss by water erosion, while the 137Cs method integrates soil loss due to all erosion agents involved. Thus, we hypothesise that the soil erosion rates determined with the 137Cs method are higher and that the observed discrepancy between the erosion rate of RUSLE and the 137Cs method is related to snow gliding. Cumulative snow glide distance was measured for the sites in the winter 2009/2010 and modelled for the surrounding area with the Spatial Snow Glide Model (SSGM). Measured snow glide distance range from 0 to 189 cm with lower values for the north exposed slopes. We observed a reduction of snow glide distance with increasing surface roughness of the vegetation, which is an important information with respect to conservation planning and expected land use changes in the Alps. Our hypothesis was confirmed, the difference of RUSLE and 137Cs erosion rates was correlated to the measured snow glide distance (R2 = 0.73; p < 0.005). A high difference (lower proportion of water erosion compared to total net erosion) was observed for high snow glide rates and vice versa. The SSGM reproduced the relative difference of the measured snow glide values between different land use/land cover types. The resulting map highlights the relevance of snow gliding for large parts of the investigated area. Based on these results, we conclude that snow gliding is a key process impacting soil erosion pattern and magnitude in sub-alpine areas with similar

  17. Efficiency of lift production in flapping and gliding flight of swifts.

    PubMed

    Henningsson, Per; Hedenström, Anders; Bomphrey, Richard J

    2014-01-01

    Many flying animals use both flapping and gliding flight as part of their routine behaviour. These two kinematic patterns impose conflicting requirements on wing design for aerodynamic efficiency and, in the absence of extreme morphing, wings cannot be optimised for both flight modes. In gliding flight, the wing experiences uniform incident flow and the optimal shape is a high aspect ratio wing with an elliptical planform. In flapping flight, on the other hand, the wing tip travels faster than the root, creating a spanwise velocity gradient. To compensate, the optimal wing shape should taper towards the tip (reducing the local chord) and/or twist from root to tip (reducing local angle of attack). We hypothesised that, if a bird is limited in its ability to morph its wings and adapt its wing shape to suit both flight modes, then a preference towards flapping flight optimization will be expected since this is the most energetically demanding flight mode. We tested this by studying a well-known flap-gliding species, the common swift, by measuring the wakes generated by two birds, one in gliding and one in flapping flight in a wind tunnel. We calculated span efficiency, the efficiency of lift production, and found that the flapping swift had consistently higher span efficiency than the gliding swift. This supports our hypothesis and suggests that even though swifts have been shown previously to increase their lift-to-drag ratio substantially when gliding, the wing morphology is tuned to be more aerodynamically efficient in generating lift during flapping. Since body drag can be assumed to be similar for both flapping and gliding, it follows that the higher total drag in flapping flight compared with gliding flight is primarily a consequence of an increase in wing profile drag due to the flapping motion, exceeding the reduction in induced drag. PMID:24587260

  18. Model tests of gliding with different hindwing configurations in the four-winged dromaeosaurid Microraptor gui

    PubMed Central

    Alexander, David E.; Gong, Enpu; Martin, Larry D.; Burnham, David A.; Falk, Amanda R.

    2010-01-01

    Fossils of the remarkable dromaeosaurid Microraptor gui and relatives clearly show well-developed flight feathers on the hind limbs as well as the front limbs. No modern vertebrate has hind limbs functioning as independent, fully developed wings; so, lacking a living example, little agreement exists on the functional morphology or likely flight configuration of the hindwing. Using a detailed reconstruction based on the actual skeleton of one individual, cast in the round, we developed light-weight, three-dimensional physical models and performed glide tests with anatomically reasonable hindwing configurations. Models were tested with hindwings abducted and extended laterally, as well as with a previously described biplane configuration. Although the hip joint requires the hindwing to have at least 20° of negative dihedral (anhedral), all configurations were quite stable gliders. Glide angles ranged from 3° to 21° with a mean estimated equilibrium angle of 13.7°, giving a lift to drag ratio of 4.1:1 and a lift coefficient of 0.64. The abducted hindwing model’s equilibrium glide speed corresponds to a glide speed in the living animal of 10.6 m·s−1. Although the biplane model glided almost as well as the other models, it was structurally deficient and required an unlikely weight distribution (very heavy head) for stable gliding. Our model with laterally abducted hindwings represents a biologically and aerodynamically reasonable configuration for this four-winged gliding animal. M. gui’s feathered hindwings, although effective for gliding, would have seriously hampered terrestrial locomotion. PMID:20133792

  19. Strongly gliding harmonic tremor during the 2009 eruption of Redoubt Volcano

    USGS Publications Warehouse

    Hotovec, Alicia J.; Prejean, Stephanie G.; Vidale, John E.; Gomberg, Joan S.

    2013-01-01

    During the 2009 eruption of Redoubt Volcano, Alaska, gliding harmonic tremor occurred prominently before six nearly consecutive explosions during the second half of the eruptive sequence. The fundamental frequency repeatedly glided upward from < 1 Hz to as high as 30 Hz in less than 10 min, followed by a relative seismic quiescence of 10 to 60 s immediately prior to explosion. High frequency (5 to 20 Hz) gliding returned during the extrusive phase, and lasted for 20 min to 3 h at a time. Although harmonic tremor is not uncommon at volcanoes, tremor at such high frequencies is a rare observation. These frequencies approach or exceed the plausible upper limits of many models that have been suggested for volcanic tremor. We also analyzed the behavior of a swarm of repeating earthquakes that immediately preceded the first instance of pre-explosion gliding harmonic tremor. We find that these earthquakes share several traits with upward gliding harmonic tremor, and favor the explanation that the gliding harmonic tremor at Redoubt Volcano is created by the superposition of increasingly frequent and regular, repeating stick–slip earthquakes through the Dirac comb effect.

  20. Harmonic Tremor and Gliding: Acoustic Chug Swarms at Tungurahua, Ecuador

    NASA Astrophysics Data System (ADS)

    Lees, J. M.; Ruiz, M. C.

    2010-12-01

    On May 28, 2010, a new eruptive episode started at Tungurahua volcano with a mid-size volcanic explosion, followed by a sustained ash emission with high ash column (10 km high), pyroclastic flows running down western and southern flanks and seismic and infrasonic tremor. After a quiescence period of 5 hours, Tungurahua Volcano in Ecuador experienced a major swarm of volcanic explosions including hundreds of events recorded up to June 18, 2010 on seismic and acoustic instrumentation in the vicinity of the active vent. Explosions exhibited extremely high excess pressures in the infrasonic band as well as in the audio band. Thirteen events produced pressures larger than 160 dB at 1 km distance from the vent. Among the diverse signals recorded during the week long episode of explosive activity, numerous sequences of harmonic tremor show significant patterns of modulation, or frequency gliding. Some harmonic tremor extended for as long as 30 minutes, often with as many as 10 different regimes of distinct behavior in one sequence of explosions. We applied automated search ridge identification using Gabor and Wavelet transforms in conjunction with time-domain analyses to derive high precision estimates of time varying periodicities. One pattern observed was a rise in dominant frequency as the tremor amplitude diminished prior to the onset of a second sequence of nearly monotonic pulsations. We speculate that these relate to conduit piston effects when the loss of gas pressure below a debris plug vibrates at shorter periods as the amplitude of the plug motion weakens.

  1. Loop formation of microtubules during gliding at high density

    NASA Astrophysics Data System (ADS)

    Liu, Lynn; Tüzel, Erkan; Ross, Jennifer L.

    2011-09-01

    The microtubule cytoskeleton, including the associated proteins, forms a complex network essential to multiple cellular processes. Microtubule-associated motor proteins, such as kinesin-1, travel on microtubules to transport membrane bound vesicles across the crowded cell. Other motors, such as cytoplasmic dynein and kinesin-5, are used to organize the cytoskeleton during mitosis. In order to understand the self-organization processes of motors on microtubules, we performed filament-gliding assays with kinesin-1 motors bound to the cover glass with a high density of microtubules on the surface. To observe microtubule organization, 3% of the microtubules were fluorescently labeled to serve as tracers. We find that microtubules in these assays are not confined to two dimensions and can cross one other. This causes microtubules to align locally with a relatively short correlation length. At high density, this local alignment is enough to create 'intersections' of perpendicularly oriented groups of microtubules. These intersections create vortices that cause microtubules to form loops. We characterize the radius of curvature and time duration of the loops. These different behaviors give insight into how crowded conditions, such as those in the cell, might affect motor behavior and cytoskeleton organization.

  2. Take-off and landing kinetics of a free-ranging gliding mammal, the Malayan colugo (Galeopterus variegatus)

    PubMed Central

    Byrnes, Greg; Lim, Norman T.-L; Spence, Andrew J

    2008-01-01

    Arboreal animals negotiate a highly three-dimensional world that is discontinuous on many spatial scales. As the scale of substrate discontinuity increases, many arboreal animals rely on leaping or gliding locomotion between distant supports. In order to successfully move through their habitat, gliding animals must actively modulate both propulsive and aerodynamic forces. Here we examined the take-off and landing kinetics of a free-ranging gliding mammal, the Malayan colugo (Galeopterus variegatus) using a custom-designed three-dimensional accelerometry system. We found that colugos increase the propulsive impulse to affect longer glides. However, we also found that landing forces are negatively associated with glide distance. Landing forces decrease rapidly as glide distance increases from the shortest glides, then level off, suggesting that the ability to reorient the aerodynamic forces prior to landing is an important mechanism to reduce velocity and thus landing forces. This ability to substantially alter the aerodynamic forces acting on the patagial wing in order to reorient the body is a key to the transition between leaping and gliding and allows gliding mammals to travel long distances between trees with reduced risk of injury. Longer glides may increase the access to distributed resources and reduce the exposure to predators in the canopy or on the forest floor. PMID:18252673

  3. Inflammation-inducing Factors of Mycoplasma pneumoniae

    PubMed Central

    Shimizu, Takashi

    2016-01-01

    Mycoplasma pneumoniae, which causes mycoplasmal pneumonia in human, mainly causes pneumonia in children, although it occasionally causes disease in infants and geriatrics. Some pathogenic factors produced by M. pneumoniae, such as hydrogen peroxide and Community-Acquired Respiratory Distress Syndrome (CARDS) toxin have been well studied. However, these factors alone cannot explain this predilection. The low incidence rate of mycoplasmal pneumonia in infants and geriatrics implies that the strong inflammatory responses induced by M. pneumoniae coordinate with the pathogenic factors to induce pneumonia. However, M. pneumoniae lacks a cell wall and does not possess an inflammation-inducing endotoxin, such as lipopolysaccharide (LPS). In M. pneumoniae, lipoproteins were identified as an inflammation-inducing factor. Lipoproteins induce inflammatory responses through Toll-like receptors (TLR) 2. Because Mycoplasma species lack a cell wall and lipoproteins anchored in the membrane are exposed, lipoproteins and TLR2 have been thought to be important for the pathogenesis of M. pneumoniae. However, recent reports suggest that M. pneumoniae also induces inflammatory responses also in a TLR2-independent manner. TLR4 and autophagy are involved in this TLR2-independent inflammation. In addition, the CARDS toxin or M. pneumoniae cytadherence induces inflammatory responses through an intracellular receptor protein complex called the inflammasome. In this review, the inflammation-inducing factors of M. pneumoniae are summarized. PMID:27065977

  4. Flight Modes in Migrating European Bee-Eaters: Heart Rate May Indicate Low Metabolic Rate during Soaring and Gliding

    PubMed Central

    Sapir, Nir; Wikelski, Martin; McCue, Marshall D.; Pinshow, Berry; Nathan, Ran

    2010-01-01

    Background Many avian species soar and glide over land. Evidence from large birds (mb>0.9 kg) suggests that soaring-gliding is considerably cheaper in terms of energy than flapping flight, and costs about two to three times the basal metabolic rate (BMR). Yet, soaring-gliding is considered unfavorable for small birds because migration speed in small birds during soaring-gliding is believed to be lower than that of flapping flight. Nevertheless, several small bird species routinely soar and glide. Methodology/Principal Findings To estimate the energetic cost of soaring-gliding flight in small birds, we measured heart beat frequencies of free-ranging migrating European bee-eaters (Merops apiaster, mb∼55 g) using radio telemetry, and established the relationship between heart beat frequency and metabolic rate (by indirect calorimetry) in the laboratory. Heart beat frequency during sustained soaring-gliding was 2.2 to 2.5 times lower than during flapping flight, but similar to, and not significantly different from, that measured in resting birds. We estimated that soaring-gliding metabolic rate of European bee-eaters is about twice their basal metabolic rate (BMR), which is similar to the value estimated in the black-browed albatross Thalassarche (previously Diomedea) melanophrys, mb∼4 kg). We found that soaring-gliding migration speed is not significantly different from flapping migration speed. Conclusions/Significance We found no evidence that soaring-gliding speed is slower than flapping flight in bee-eaters, contradicting earlier estimates that implied a migration speed penalty for using soaring-gliding rather than flapping flight. Moreover, we suggest that small birds soar and glide during migration, breeding, dispersal, and other stages in their annual cycle because it may entail a low energy cost of transport. We propose that the energy cost of soaring-gliding may be proportional to BMR regardless of bird size, as theoretically deduced by earlier studies

  5. Mycoplasma pneumoniae induces cytotoxic activity in guinea pig bronchoalveolar cells

    SciTech Connect

    Kist, M.; Koester, H.; Bredt, W.

    1985-06-01

    Precultured guinea pig alveolar macrophages (AM) and freshly harvested alveolar cells (FHAC) activated by interaction with Mycoplasma pneumoniae were cytotoxic for xenogeneic /sup 75/selenomethionine-labeled tumor target cells. Phagocytosis of whole opsonized or nonopsonized M. pneumoniae cells was more effective in eliciting cytotoxicity than uptake of sonicated microorganisms. The addition of living mycoplasma cells to the assay system enhanced the cytotoxic effect considerably. Target cells were significantly more susceptible to the cytotoxic action of phagocytes if they were coated with mycoplasma antigen or cocultured together with M. pneumoniae. The activation of the phagocytes could be inhibited by 2-deoxy-D-glucose but not by antimicrobial substances suppressing mycoplasma protein synthesis. It was accompanied by /sup 51/Cr release without detectable signs of cell damage. The supernatants of activated cells were cytotoxic for approximately 24 h. Inhibition, release, and cytotoxic activity indicate the necessity of an intact metabolism of the effector cells and suggest a secretion of cytotoxic substances.

  6. IDENTIFICATION OF IMMUNOGENS OF 'MYCOPLASMA PNEUMONIAE' BY PROTEIN BLOTTING

    EPA Science Inventory

    Proteins of Mycoplasma pneumoniae were separated by SDS-polyacrylamide gel electrophoresis and transferred to a nitrocellulose sheet by blotting. Sera obtained from infected hamsters and immunized rabbits were then incubated with the nitrocellulose strips. Proteins which are capa...

  7. Susceptibilities of Mycoplasma bovis, Mycoplasma dispar, and Ureaplasma diversum strains to antimicrobial agents in vitro.

    PubMed Central

    ter Laak, E A; Noordergraaf, J H; Verschure, M H

    1993-01-01

    The purpose of this study was to determine the susceptibility of various strains of Mycoplasma bovis, Mycoplasma dispar, and Ureaplasma diversum, which are prevalent causes of pneumonia in calves, to 16 antimicrobial agents in vitro. The MICs of the antimicrobial agents were determined by a serial broth dilution method for 16 field strains and the type strain of M. bovis, for 19 field strains and the type strain of M. dispar, and for 17 field strains of U. diversum. Final MICs for M. bovis and M. dispar were read after 7 days and final MICs for U. diversum after 1 to 2 days. All strains tested were susceptible to tylosin, kitasamycin, and tiamulin but were resistant to nifuroquine and streptomycin. Most strains of U. diversum were intermediately susceptible to oxytetracycline but fully susceptible to chlortetracycline; most strains of M. bovis and M. dispar, however, were resistant to both agents. Strains of M. dispar and U. diversum were susceptible to doxycycline and minocycline, but strains of M. bovis were only intermediately susceptible. Susceptibility or resistance to chloramphenicol, spiramycin, spectinomycin, lincomycin, or enrofloxacin depended on the species but was not equal for the three species. The type strains of M. bovis and M. dispar were more susceptible to various antimicrobial agents, including tetracyclines, than the field strains. This finding might indicate that M. bovis and M. dispar strains are becoming resistant to these agents. Antimicrobial agents that are effective in vitro against all three mycoplasma species can be considered for treating mycoplasma infections in pneumonic calves. Therefore, tylosin, kitasamycin, and tiamulin may be preferred over oxytetracycline and chlortetracycline. PMID:8452363

  8. Selective inhibition of DNA amplification in nonadhering Mycoplasma pneumoniae cultures

    SciTech Connect

    Zigangirova, N.A.; Solov`eva, S.V.; Rakovskaya, I.V.

    1995-08-01

    Inhibition of amplification of various genome regions of Mycoplasma pneumoniae was observed in the polymerase chain reaction, and was dependent on cultivation conditions. A protein stably associated with DNA is responsible for the inhibitory effect. It is assumed that when the protein selectively associates with separate DNA regions, it can inhibit genes encoding pathogenicity factors, thus promoting mycoplasma transformation into persistent variants. 16 refs., 2 figs.

  9. Isolation and analysis of tetracycline-resistant Mycoplasma agalactiae strains from an infected goat herd in Cyprus - short communication.

    PubMed

    Filioussis, George; Ioannou, Ioannis; Petridou, Evanthia; Avraam, Maria; Giadinis, Nektarios D; Kritas, Spyridon K

    2013-09-01

    A major concern with the use of tetracycline against mycoplasmas is the development of resistance. Infections in small ruminants due to tetracyclineresistant Mycoplasma agalactiae strains are becoming a frequent problem worldwide. In the present paper the detection and analysis of three tetracycline-resistant M. agalactiae strains, isolated from infected goats in Cyprus, are reported. The three field isolates were identified as M. agalactiae by polymerase chain reaction (PCR) showing 98% identity to the M. agalactiae PG2 reference strain. Furthermore, they were found sensitive to tylosin, enrofloxacin, spiramycin and lincomycin. In contrast, they were resistant to tetracycline. None of the putative genes [tet(M), tet(O) and tet(S)] that commonly contribute to high-level resistance to tetracycline could be amplified from their genome. Contrarily, the field isolates were found to carry ISMag1, an insertion sequence related to the IS30 family of mobile elements. Although ISMag1 is widely believed to induce high-frequency chromosomal rearrangements resulting in phenotypic changes of microorganisms, its potential role in tetracycline resistance of mycoplasmas requires further studies. PMID:23921341

  10. Is Mycoplasma synoviae outrunning Mycoplasma gallisepticum? A viewpoint from the Netherlands.

    PubMed

    Landman, Wil J M

    2014-01-01

    Mycoplasma gallisepticum and M. synoviae are the most relevant mycoplasma species for commercial poultry from the clinical and economic point of view. Although the importance of M. gallisepticum was recognized many decades ago, the relevance of M. synoviae has been a matter of debate. Until the turn of the century, only the respiratory and synovitis forms of the disease were reported, while the majority of infections were subclinical. Since the year 2000 M. synoviae strains with oviduct tropism, able to induce eggshell apex abnormalities and egg drops, have been encountered worldwide. A decreasing incidence of M. gallisepticum has been observed, at least in breeding stock, in countries with control and eradication programmes for this Mycoplasma species. In contrast, the sero-prevalence of M. synoviae is much higher, especially in layer flocks, and in most continents exceeds 70%. Given the emergence of virulent M. synoviae strains with oviduct tropism, its ability to also induce joint and respiratory disease, to act synergistically with other pathogens as well as its much higher sero-prevalence, it seems that M. synoviae is outrunning M. gallisepticum, at least in countries with control and eradication programmes for the latter. This stresses the need to update M. synoviae prevention and control strategies. Thus, in January 2013, the Dutch poultry industry implemented a mandatory control and eradication programme for M. synoviae at all levels of poultry farming with the exception of broilers. PMID:24397240

  11. Urogenital Mycoplasmas and Human Papilloma Virus in Hemodialysed Women

    PubMed Central

    Ekiel, Alicja; Pietrzak, Bronisława; Aptekorz, Małgorzata; Mazanowska, Natalia; Kamiński, Paweł; Martirosian, Gayane

    2013-01-01

    Bacterial infections, especially endogenous, are the frequent complications among hemodialyzed and renal transplant patients. In this study we assumed the prevalence of urogenital mycoplasmas and HPV among hemodialysed women. We examined 32 hemodialysed women aged 20–48 (mean 35.6 ± 8.23) and 100 healthy controls of the same ages. Two swabs were collected for detection of mycoplasmas and HPV. Culture of Ureaplasma spp. and M. hominis was performed using Mycoplasma IST2 (bioMérieux, France), Identificaton of U. parvum and U. urealyticum was performed by Kong. Primers described by Jensen were used for M. genitalium. For detection of high-risk HPV types Amplicor HPV (Roche Molecular System, CA) was used. Prevalence of urogenital mycoplasmas in the hemodialysed women (53.1%) was significantly higher (P = 0.0059), compared with controls (25%). In both groups, U. parvum was the most frequently isolated. Cooccurrence of urogenital mycoplasmas was shown in 75% of the HPV-positive hemodialysed women and in 30.4% of HPV-positive controls (P = 0.0461). Cooccurrence of urogenital mycoplasmas with HPV was significantly higher in hemodialysed women. The need to take into account these microorganisms in routine diagnostic, especially for hemodialysed patients, was demonstrated. Further studies to demonstrate the role of this cooccurrence in etiopathogenesis of infection in hemodialysed patients are required. PMID:24363622

  12. Urogenital mycoplasmas and human papilloma virus in hemodialysed women.

    PubMed

    Ekiel, Alicja; Pietrzak, Bronisława; Wiechuła, Barbara; Aptekorz, Małgorzata; Mazanowska, Natalia; Rady, Dominika; Kamiński, Paweł; Martirosian, Gayane

    2013-01-01

    Bacterial infections, especially endogenous, are the frequent complications among hemodialyzed and renal transplant patients. In this study we assumed the prevalence of urogenital mycoplasmas and HPV among hemodialysed women. We examined 32 hemodialysed women aged 20-48 (mean 35.6 ± 8.23) and 100 healthy controls of the same ages. Two swabs were collected for detection of mycoplasmas and HPV. Culture of Ureaplasma spp. and M. hominis was performed using Mycoplasma IST2 (bioMérieux, France), Identificaton of U. parvum and U. urealyticum was performed by Kong. Primers described by Jensen were used for M. genitalium. For detection of high-risk HPV types Amplicor HPV (Roche Molecular System, CA) was used. Prevalence of urogenital mycoplasmas in the hemodialysed women (53.1%) was significantly higher (P = 0.0059), compared with controls (25%). In both groups, U. parvum was the most frequently isolated. Cooccurrence of urogenital mycoplasmas was shown in 75% of the HPV-positive hemodialysed women and in 30.4% of HPV-positive controls (P = 0.0461). Cooccurrence of urogenital mycoplasmas with HPV was significantly higher in hemodialysed women. The need to take into account these microorganisms in routine diagnostic, especially for hemodialysed patients, was demonstrated. Further studies to demonstrate the role of this cooccurrence in etiopathogenesis of infection in hemodialysed patients are required. PMID:24363622

  13. Genomic repeats, genome plasticity and the dynamics of Mycoplasma evolution

    PubMed Central

    Rocha, Eduardo P. C.; Blanchard, Alain

    2002-01-01

    Mycoplasmas evolved by a drastic reduction in genome size, but their genomes contain numerous repeated sequences with important roles in their evolution. We have established a bioinformatic strategy to detect the major recombination hot-spots in the genomes of Mycoplasma pneumoniae, Mycoplasma genitalium, Ureaplasma urealyticum and Mycoplasma pulmonis. This allowed the identification of large numbers of potentially variable regions, as well as a comparison of the relative recombination potentials of different genomic regions. Different trends are perceptible among mycoplasmas, probably due to different functional and structural constraints. The largest potential for illegitimate recombination in M.pulmonis is found at the vsa locus and its comparison in two different strains reveals numerous changes since divergence. On the other hand, the main M.pneumoniae and M.genitalium adhesins rely on large distant repeats and, hence, homologous recombination for variation. However, the relation between the existence of repeats and antigenic variation is not necessarily straightforward, since repeats of P1 adhesin were found to be anti-correlated with epitopes recognized by patient antibodies. These different strategies have important consequences for the structures of genomes, since large distant repeats correlate well with the major chromosomal rearrangements. Probably to avoid such events, mycoplasmas strongly avoid inverse repeats, in comparison to co-oriented repeats. PMID:11972343

  14. Role of Vpma phase variation in Mycoplasma agalactiae pathogenesis

    PubMed Central

    Chopra-Dewasthaly, Rohini; Baumgartner, Martina; Gamper, Erika; Innerebner, Carmen; Zimmermann, Martina; Schilcher, Franz; Tichy, Alexander; Winter, Petra; Rosengarten, Renate; Spergser, Joachim

    2015-01-01

    Compared with other bacterial pathogens, the molecular mechanisms of mycoplasma pathogenicity are largely unknown. Several studies in the past have shown that pathogenic mycoplasmas are equipped with sophisticated genetic systems that allow them to undergo high-frequency surface antigenic variations. Although never clearly proven, these variable mycoplasma surface components are often implicated in host immune evasion and adaptation. Vpma surface lipoproteins of the ruminant pathogen Mycoplasma agalactiae are encoded on a genomic pathogenicity island–like locus and are considered as one of the well-characterized model systems of mycoplasma surface antigenic variation. The present study assesses the role of these phase-variable Vpmas in the molecular pathogenesis of M. agalactiae by testing the wild-type strain PG2 in comparison with the xer1-disrupted Vpma ‘phase-locked’ mutants in sheep infection models. The data clearly illustrate that although Xer1 recombinase is not a virulence factor of M. agalactiae and Vpma phase variation is not necessary for establishing an infection, it might critically influence the survival and persistence of the pathogen under natural field conditions, mainly due to a better capacity for dissemination and evoking systemic responses. This is the first study where mycoplasma ‘phase-locked’ mutants are tested in vivo to elucidate the role of phase variation during infection. PMID:22809092

  15. A Mycoplasma species of Emydidae turtles in the northeastern USA.

    PubMed

    Ossiboff, Robert J; Raphael, Bonnie L; Ammazzalorso, Alyssa D; Seimon, Tracie A; Niederriter, Holly; Zarate, Brian; Newton, Alisa L; McAloose, Denise

    2015-04-01

    Mycoplasma infections can cause significant morbidity and mortality in captive and wild chelonians. As part of a health assessment of endangered bog turtles (Glyptemys muhlenbergii) in the northeastern US, choanal and cloacal swabs from these and other sympatric species, including spotted turtles (Clemmys guttata), eastern box turtles (Terrapene carolina carolina), wood turtles (Glyptemys insculpta), and common snapping turtles (Chelydra serpentina) from 10 sampling sites in the states (US) of Delaware, New Jersey, and Pennsylvania, were tested by PCR for Mycoplasma. Of 108 turtles tested, 63 (58.3%) were PCR positive for Mycoplasma including 58 of 83 bog turtles (70%), three of three (100%) eastern box turtles, and two of 11 (18%) spotted turtles; all snapping turtles (n = 7) and wood turtles (n = 4) were negative. Sequence analysis of portions of the 16S-23S intergenic spacer region and the 16S ribosomal RNA gene revealed a single, unclassified species of Mycoplasma that has been previously reported in eastern box turtles, ornate box turtles (Terrapene ornata ornata), western pond turtles (Emys marmorata), and red-eared sliders (Trachemys scripta elegans). We document a high incidence of Mycoplasma, in the absence of clinical disease, in wild emydid turtles. These findings, along with wide distribution of the identified Mycoplasma sp. across a broad geographic region, suggest this bacterium is likely a commensal inhabitant of bog turtles, and possibly other species of emydid turtles, in the northeastern US. PMID:25574806

  16. Effects of Glide Path on the Centering Ability and Preparation Time of Two Reciprocating Instruments

    PubMed Central

    Coelho, Marcelo Santos; Fontana, Carlos Eduardo; Kato, Augusto Shoji; de Martin, Alexandre Sigrist; da Silveira Bueno, Carlos Eduardo

    2016-01-01

    Introduction: The aim of this in vitro study was to evaluate the effects of establishing glide path on the centering ability and preparation time of two single-file reciprocating systems in mesial root canals of mandibular molars. Methods and Materials: Sixty extracted mandibular molars with curvatures of 25-39 degrees and separate foramina for the mesiobuccal and mesiolingual canals, were divided into four groups (n=15); WaveOne+glide path; WaveOne; Reciproc+glide path and Reciproc. Non-patent canals were excluded and only one canal in each tooth was instrumented. A manual glide path was established in first and third groups with #10, 15 and 20 hand K-files. Preparation was performed with reciprocating in-and-out motion, with a 3-4 mm amplitude and slight apical pressure. Initial and final radiographs were taken to analyze the amount of dentin removed in the instrumented canals. The radiographs were superimposed with an image editing software and examined to assess discrepancies at 3-, 6- and 9-mm distances from the apex. The Kruskal-Wallis test was used for statistical analysis. The level of significance was set at 0.05. Results: Preparation in groups without glide paths was swifter than the other groups (P=0.001). However, no difference was observed regarding centering ability. Conclusion: Establishing a glide path increased the total instrumentation time for preparing curved canals with WaveOne and Reciproc instruments. Glide path had no influence on the centering ability of these systems. PMID:26843875

  17. Swine and poultry pathogens: the complete genome sequences of two strains of Mycoplasma hyopneumoniae and a strain of Mycoplasma synoviae.

    PubMed

    Vasconcelos, Ana Tereza R; Ferreira, Henrique B; Bizarro, Cristiano V; Bonatto, Sandro L; Carvalho, Marcos O; Pinto, Paulo M; Almeida, Darcy F; Almeida, Luiz G P; Almeida, Rosana; Alves-Filho, Leonardo; Assunção, Enedina N; Azevedo, Vasco A C; Bogo, Maurício R; Brigido, Marcelo M; Brocchi, Marcelo; Burity, Helio A; Camargo, Anamaria A; Camargo, Sandro S; Carepo, Marta S; Carraro, Dirce M; de Mattos Cascardo, Júlio C; Castro, Luiza A; Cavalcanti, Gisele; Chemale, Gustavo; Collevatti, Rosane G; Cunha, Cristina W; Dallagiovanna, Bruno; Dambrós, Bibiana P; Dellagostin, Odir A; Falcão, Clarissa; Fantinatti-Garboggini, Fabiana; Felipe, Maria S S; Fiorentin, Laurimar; Franco, Gloria R; Freitas, Nara S A; Frías, Diego; Grangeiro, Thalles B; Grisard, Edmundo C; Guimarães, Claudia T; Hungria, Mariangela; Jardim, Sílvia N; Krieger, Marco A; Laurino, Jomar P; Lima, Lucymara F A; Lopes, Maryellen I; Loreto, Elgion L S; Madeira, Humberto M F; Manfio, Gilson P; Maranhão, Andrea Q; Martinkovics, Christyanne T; Medeiros, Sílvia R B; Moreira, Miguel A M; Neiva, Márcia; Ramalho-Neto, Cicero E; Nicolás, Marisa F; Oliveira, Sergio C; Paixão, Roger F C; Pedrosa, Fábio O; Pena, Sérgio D J; Pereira, Maristela; Pereira-Ferrari, Lilian; Piffer, Itamar; Pinto, Luciano S; Potrich, Deise P; Salim, Anna C M; Santos, Fabrício R; Schmitt, Renata; Schneider, Maria P C; Schrank, Augusto; Schrank, Irene S; Schuck, Adriana F; Seuanez, Hector N; Silva, Denise W; Silva, Rosane; Silva, Sérgio C; Soares, Célia M A; Souza, Kelly R L; Souza, Rangel C; Staats, Charley C; Steffens, Maria B R; Teixeira, Santuza M R; Urmenyi, Turan P; Vainstein, Marilene H; Zuccherato, Luciana W; Simpson, Andrew J G; Zaha, Arnaldo

    2005-08-01

    This work reports the results of analyses of three complete mycoplasma genomes, a pathogenic (7448) and a nonpathogenic (J) strain of the swine pathogen Mycoplasma hyopneumoniae and a strain of the avian pathogen Mycoplasma synoviae; the genome sizes of the three strains were 920,079 bp, 897,405 bp, and 799,476 bp, respectively. These genomes were compared with other sequenced mycoplasma genomes reported in the literature to examine several aspects of mycoplasma evolution. Strain-specific regions, including integrative and conjugal elements, and genome rearrangements and alterations in adhesin sequences were observed in the M. hyopneumoniae strains, and all of these were potentially related to pathogenicity. Genomic comparisons revealed that reduction in genome size implied loss of redundant metabolic pathways, with maintenance of alternative routes in different species. Horizontal gene transfer was consistently observed between M. synoviae and Mycoplasma gallisepticum. Our analyses indicated a likely transfer event of hemagglutinin-coding DNA sequences from M. gallisepticum to M. synoviae. PMID:16077101

  18. Swine and Poultry Pathogens: the Complete Genome Sequences of Two Strains of Mycoplasma hyopneumoniae and a Strain of Mycoplasma synoviae†

    PubMed Central

    Vasconcelos, Ana Tereza R.; Ferreira, Henrique B.; Bizarro, Cristiano V.; Bonatto, Sandro L.; Carvalho, Marcos O.; Pinto, Paulo M.; Almeida, Darcy F.; Almeida, Luiz G. P.; Almeida, Rosana; Alves-Filho, Leonardo; Assunção, Enedina N.; Azevedo, Vasco A. C.; Bogo, Maurício R.; Brigido, Marcelo M.; Brocchi, Marcelo; Burity, Helio A.; Camargo, Anamaria A.; Camargo, Sandro S.; Carepo, Marta S.; Carraro, Dirce M.; de Mattos Cascardo, Júlio C.; Castro, Luiza A.; Cavalcanti, Gisele; Chemale, Gustavo; Collevatti, Rosane G.; Cunha, Cristina W.; Dallagiovanna, Bruno; Dambrós, Bibiana P.; Dellagostin, Odir A.; Falcão, Clarissa; Fantinatti-Garboggini, Fabiana; Felipe, Maria S. S.; Fiorentin, Laurimar; Franco, Gloria R.; Freitas, Nara S. A.; Frías, Diego; Grangeiro, Thalles B.; Grisard, Edmundo C.; Guimarães, Claudia T.; Hungria, Mariangela; Jardim, Sílvia N.; Krieger, Marco A.; Laurino, Jomar P.; Lima, Lucymara F. A.; Lopes, Maryellen I.; Loreto, Élgion L. S.; Madeira, Humberto M. F.; Manfio, Gilson P.; Maranhão, Andrea Q.; Martinkovics, Christyanne T.; Medeiros, Sílvia R. B.; Moreira, Miguel A. M.; Neiva, Márcia; Ramalho-Neto, Cicero E.; Nicolás, Marisa F.; Oliveira, Sergio C.; Paixão, Roger F. C.; Pedrosa, Fábio O.; Pena, Sérgio D. J.; Pereira, Maristela; Pereira-Ferrari, Lilian; Piffer, Itamar; Pinto, Luciano S.; Potrich, Deise P.; Salim, Anna C. M.; Santos, Fabrício R.; Schmitt, Renata; Schneider, Maria P. C.; Schrank, Augusto; Schrank, Irene S.; Schuck, Adriana F.; Seuanez, Hector N.; Silva, Denise W.; Silva, Rosane; Silva, Sérgio C.; Soares, Célia M. A.; Souza, Kelly R. L.; Souza, Rangel C.; Staats, Charley C.; Steffens, Maria B. R.; Teixeira, Santuza M. R.; Urmenyi, Turan P.; Vainstein, Marilene H.; Zuccherato, Luciana W.; Simpson, Andrew J. G.; Zaha, Arnaldo

    2005-01-01

    This work reports the results of analyses of three complete mycoplasma genomes, a pathogenic (7448) and a nonpathogenic (J) strain of the swine pathogen Mycoplasma hyopneumoniae and a strain of the avian pathogen Mycoplasma synoviae; the genome sizes of the three strains were 920,079 bp, 897,405 bp, and 799,476 bp, respectively. These genomes were compared with other sequenced mycoplasma genomes reported in the literature to examine several aspects of mycoplasma evolution. Strain-specific regions, including integrative and conjugal elements, and genome rearrangements and alterations in adhesin sequences were observed in the M. hyopneumoniae strains, and all of these were potentially related to pathogenicity. Genomic comparisons revealed that reduction in genome size implied loss of redundant metabolic pathways, with maintenance of alternative routes in different species. Horizontal gene transfer was consistently observed between M. synoviae and Mycoplasma gallisepticum. Our analyses indicated a likely transfer event of hemagglutinin-coding DNA sequences from M. gallisepticum to M. synoviae. PMID:16077101

  19. Mycoplasma hyorhinis and Mycoplasma fermentans induce cell apoptosis and changes in gene expression profiles of 32D cells.

    PubMed

    Liu, Wenbin; Shou, Chengchao

    2011-01-01

    Infection of mycoplasmas has been linked to various human diseases including arthritis, pneumonia, infertility and cancer. While Mycoplasma hyorhinis and Mycoplasma fermentans have been detected in gastric adenocarcinomas, the mechanisms underlyine the pathogenesis are unknown. In this study, cell growth kinetics, Hoechst 33258 staining, DNA ladder assays, Western blotting analysis and cDNA microarray assays were performed to investigate the roles of M. hyorhinis and M. fermentans during infection of mammalian cells. Our data demonstrated that these mycoplasmas inhibid the growth of immortalised cell lines (32D and COS-7) ane tumor cell lines (HeLa and AGS). In addition, the infection of the 32D cell line with M. hyorhinis and M. fermentans induced compression of the nucleus, degradation of the cell genome and dysregulation of the expression of genes related to proliferation, apoptosis, tumorigenesis, signaling pathway and metabolism. Apoptosis related proteins Bcl-2, Bid and p53 were down-regulated, Fas was up-regulated and Bax was dysregulated in mycoplasma-infected 32D cells. Together, our data demonstrated that infection of mycoplasmas inhibitd cele growts through modification of gene expression profiles and post-translation modification of proliferation and apoptosis related proteins. PMID:22446603

  20. Characterization of triosephosphate isomerase from Mycoplasma gallisepticum.

    PubMed

    Bao, Shijun; Chen, Danqing; Yu, Shengqing; Chen, Hongjun; Tan, Lei; Hu, Meirong; Qiu, Xusheng; Song, Cuiping; Ding, Chan

    2015-09-01

    Triosephosphate isomerase (Tpi) is a glycolytic enzyme that is essential for efficient energy production in many pathogens. However, its function in Mycoplasma gallisepticum has not been fully elucidated. In this study, the mga0357 gene of M. gallisepticum, which encodes TpiA (MGTpiA), was amplified and expressed in Escherichia coli by IPTG induction. The purified recombinant MGTpiA protein exhibited catalytic activity that was similar to TPI from rabbit muscle, reducing NAD(+) to NADH. The MGTpiA was also found to be a surface-exposed protein by western blotting and immunofluorescence assays. In addition, cytadherence inhibition assays confirmed that the cytadherence of M. gallisepticum to the DF-1 cells was significantly inhibited by the anti-MGTpiA serum. The results of the study suggested that MGTpiA plays an important role in the metabolism and closely related to the M. gallisepticum pathogenicity. PMID:26319024

  1. Toxic Membrane Fractions from Mycoplasma fermentans1

    PubMed Central

    Gabridge, Michael G.; Murphy, William H.

    1971-01-01

    A recent isolate of Mycoplasma fermentans (strain K10, from human leukemic bone marrow) induced a lethal toxicity syndrome in mice. High doses of both viable and inactivated cells were toxic when injected intraperitoneally. Whole lysates and membranes from osmotically shocked cells killed mice, but cytoplasm did not. When membranes were dissolved in detergents and reaggregated by dialysis in the presence of Mg2+, the lipid-protein complex thus formed was toxic. Lipids extracted from membranes with chloroform-methanol did not kill mice. Protein-rich fractions (obtained by reaggregation plus acetone washes or ammonium sulfate precipitation of dissolved membranes) were also not toxic. No qualitative differences in proteins from three toxic isolates and three nontoxic laboratory strains of M. fermentans were detectable by polyacrylamide gel electrophoresis. The toxic factor contained in reaggregated membranes was heat-stable but sensitive to Pronase, trypsin, and lipase. Images PMID:5154902

  2. Repetitive DNA sequences in Mycoplasma pneumoniae.

    PubMed Central

    Wenzel, R; Herrmann, R

    1988-01-01

    Two types of different repetitive DNA sequences called RepMP1 and RepMP2 were identified in the genome of Mycoplasma pneumoniae. The number of these repeated elements, their nucleotide sequence and their localization on a physical map of the M. pneumoniae genome were determined. The results show that RepMP1 appears at least 10 times and RepMP2 at least 8 times in the genome. The repeated elements are dispersed on the chromosome and, in three cases, linked to each other by a homologous DNA sequence of 400 bp. The elements themselves are 300 bp (for RepMP1) and 150 bp (for RepMP2) long showing a high degree of homology. One copy of RepMP2 is a translated part of the gene for the major cytadhesin protein P1 which is responsible for the adsorption of M. pneumoniae to its host cell. Images PMID:3138660

  3. Cytoskeletal elements in the bacterium Mycoplasma pneumoniae

    NASA Astrophysics Data System (ADS)

    Hegermann, Jan; Herrmann, Richard; Mayer, Frank

    2002-09-01

    Mycoplasma pneumoniae is a pathogenic eubacterium lacking a cell wall. Three decades ago, a "rod", an intracellular cytoskeletal structure, was discovered that was assumed to define and stabilize the elongated cell shape. Later, by treatment with detergent, a "Triton shell" (i.e. a fraction of detergent-insoluble cell material) could be obtained, believed to contain additional cytoskeletal elements. Now, by application of a modified Triton X-100 treatment, we are able to demonstrate that M. pneumoniae possesses a cytoskeleton consisting of a blade-like rod and a peripheral lining located close to the inner face of the cytoplasmic membrane, exhibiting features of a highly regular network. Attached "stalks" may support the cytoplasmic membrane. The rod was connected to the cell periphery by "spokes" and showed a defined ultrastructure. Its proximal end was found to be attached to a wheel-like complex. Fibrils extended from the proximal end of the rod into the cytoplasm.

  4. Motor-Substrate Interactions in Mycoplasma Motility Explains Non-Arrhenius Temperature Dependence

    PubMed Central

    Chen, Jing; Neu, John; Miyata, Makoto; Oster, George

    2009-01-01

    Abstract Mycoplasmas exhibit a novel, substrate-dependent gliding motility that is driven by ∼400 “leg” proteins. The legs interact with the substrate and transmit the forces generated by an assembly of ATPase motors. The velocity of the cell increases linearly by nearly 10-fold over a narrow temperature range of 10–40°C. This corresponds to an Arrhenius factor that decreases from ∼45 kBT at 10°C to ∼10 kBT at 40°C. On the other hand, load-velocity curves at different temperatures extrapolate to nearly the same stall force, suggesting a temperature-insensitive force-generation mechanism near stall. In this article, we propose a leg-substrate interaction mechanism that explains the intriguing temperature sensitivity of this motility. The large Arrhenius factor at low temperature comes about from the addition of many smaller energy barriers arising from many substrate-binding sites at the distal end of the leg protein. The Arrhenius dependence attenuates at high temperature due to two factors: 1), the reduced effective multiplicity of energy barriers intrinsic to the multiple-site binding mechanism; and 2), the temperature-sensitive weakly facilitated leg release that curtails the power stroke. The model suggests an explanation for the similar steep, sub-Arrhenius temperature-velocity curves observed in many molecular motors, such as kinesin and myosin, wherein the temperature behavior is dominated not by the catalytic biochemistry, but by the motor-substrate interaction. PMID:19948122

  5. Pathogenesis of Mycoplasma pneumoniae: An update.

    PubMed

    Chaudhry, R; Ghosh, A; Chandolia, A

    2016-01-01

    Genus Mycoplasma, belonging to the class Mollicutes, encompasses unique lifeforms comprising of a small genome of 8,00,000 base pairs and the inability to produce a cell wall under any circumstances. Mycoplasma pneumoniae is the most common pathogenic species infecting humans. It is an atypical respiratory bacteria causing community acquired pneumonia (CAP) in children and adults of all ages. Although atypical pneumonia caused by M. pneumoniae can be managed in outpatient settings, complications affecting multiple organ systems can lead to hospitalization in vulnerable population. M. pneumoniae infection has also been associated with chronic lung disease and bronchial asthma. With the advent of molecular methods of diagnosis and genetic, immunological and ultrastructural assays that study infectious disease pathogenesis at subcellular level, newer virulence factors of M. pneumoniae have been recognized by researchers. Structure of the attachment organelle of the organism, that mediates the crucial initial step of cytadherence to respiratory tract epithelium through complex interaction between different adhesins and accessory adhesion proteins, has been decoded. Several subsequent virulence mechanisms like intracellular localization, direct cytotoxicity and activation of the inflammatory cascade through toll-like receptors (TLRs) leading to inflammatory cytokine mediated tissue injury, have also been demonstrated to play an essential role in pathogenesis. The most significant update in the knowledge of pathogenesis has been the discovery of Community-Acquired Respiratory Distress Syndrome toxin (CARDS toxin) of M. pneumoniae and its ability of adenosine diphosphate (ADP) ribosylation and inflammosome activation, thus initiating airway inflammation. Advances have also been made in terms of the different pathways behind the genesis of extrapulmonary complications. This article aims to comprehensively review the recent advances in the knowledge of pathogenesis of this

  6. Immunoelectrophoretic Analysis of Mycoplasma mycoides var. mycoides

    PubMed Central

    Stone, S. S.; Razin, S.

    1973-01-01

    Acrylamide gel electrophoresis was used to show the similarities and differences in the membrane proteins of two vaccine and two virulent strains of Mycoplasma mycoides var. mycoides. Immunoelectrophoretic (IEP) analysis was also used to partially characterize the associated antigens. Antibody spectra to the antigens of M. mycoides differ in rabbit, pig, and cattle sera. Rabbits produce better precipitating antibody against the anodic migrating protein mycoplasma antigens than cattle and pigs as seen in IEP. However, rabbit anti-M. mycoides serum did not show precipitating antibody against the heat-stable carbohydrate antigen. As judged by IEP, the major carbohydrate antigen extracted from the media, or boiled whole organism, is similar to that present in the sera-infected cattle and knee joints of calves. This carbohydrate antigen has a cathodic migration in IEP at pH 8.6. Periodate oxidation, classically used to destroy carbohydrate, also destroys most of the protein antigens. Heating the antigens to 56 C for 10 min destroys many of the noncarbohydrate antigens and 100 C eliminates all but the carbohydrate antigen. Extraction of M. mycoides with chloroform-methanol, phenol, ethanol, or ethanol-acetone reduced or eliminated most of the protein antigens. Some of the isolated antigenic fractions of M. mycoides were tested to determine their activity in the diagnostic complement fixation test for contagious bovine pleuropneumonia and their inhibitory effect in this test by using bovine anti-M. mycoides antisera having precipitating antibody and circulating antigen. The complement fixation antigen is not the galactan, cannot be extracted by chloroform-methanol, but is stable to boiling at 100 C and may be extracted by phenol and partially precipitated by ethanol-acetone. Images PMID:4577417

  7. Proteomics inference of genes involved in host adaptation of Mycoplasma gallinarum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Different from most other host-specific mycoplasmas, Mycoplasma gallinarum has been isolated from various hosts, such as poultry, pig, cattle, and sheep. The wide distribution among different hosts, the low pathogenesis, and the weak host immunological responses suggest this mycoplasma has a unique ...

  8. Influence of a glide path on the dentinal crack formation of ProTaper Next system

    PubMed Central

    Uzunoğlu, Emel

    2015-01-01

    Objectives The aim was to evaluate dentinal crack formation after root canal preparation with ProTaper Next system (PTN) with and without a glide path. Materials and Methods Forty-five mesial roots of mandibular first molars were selected. Fifteen teeth were left unprepared and served as controls. The experimental groups consist of mesiobuccal and mesiolingual root canals of remaining 30 teeth, which were divided into 2 groups (n = 15): Group PG/PTN, glide path was created with ProGlider (PG) and then canals were shaped with PTN system; Group PTN, glide path was not prepared and canals were shaped with PTN system only. All roots were sectioned perpendicular to the long axis at 1, 2, 3, 4, 6, and 8 mm from the apex, and the sections were observed under a stereomicroscope. The presence/absence of cracks was recorded. Data were analyzed with chi-square tests with Yates correction. Results There were no significant differences in crack formation between the PTN with and without glide path preparation. The incidence of cracks observed in PG/PTN and PTN groups was 17.8% and 28.9%, respectively. Conclusions The creation of a glide path with ProGlider before ProTaper Next rotary system did not influence dentinal crack formation in root canals. PMID:26587414

  9. Dislocation dynamics simulations of interactions between gliding dislocations and radiation induced prismatic loops in zirconium

    NASA Astrophysics Data System (ADS)

    Drouet, Julie; Dupuy, Laurent; Onimus, Fabien; Mompiou, Frédéric; Perusin, Simon; Ambard, Antoine

    2014-06-01

    The mechanical behavior of Pressurized Water Reactor fuel cladding tubes made of zirconium alloys is strongly affected by neutron irradiation due to the high density of radiation induced dislocation loops. In order to investigate the interaction mechanisms between gliding dislocations and loops in zirconium, a new nodal dislocation dynamics code, adapted to Hexagonal Close Packed metals, has been used. Various configurations have been systematically computed considering different glide planes, basal or prismatic, and different characters, edge or screw, for gliding dislocations with -type Burgers vectors. Simulations show various interaction mechanisms such as (i) absorption of a loop on an edge dislocation leading to the formation of a double super-jog, (ii) creation of a helical turn, on a screw dislocation, that acts as a strong pinning point or (iii) sweeping of a loop by a gliding dislocation. It is shown that the clearing of loops is more favorable when the dislocation glides in the basal plane than in the prismatic plane explaining the easy dislocation channeling in the basal plane observed after neutron irradiation by transmission electron microscopy.

  10. Polycomb Controls Gliogenesis by Regulating the Transient Expression of the Gcm/Glide Fate Determinant

    PubMed Central

    Diebold, Celine; Van de Bor, Véronique; Schuettengruber, Bernd; González, Inma; Busturia, Ana; Cavalli, Giacomo; Giangrande, Angela

    2012-01-01

    The Gcm/Glide transcription factor is transiently expressed and required in the Drosophila nervous system. Threshold Gcm/Glide levels control the glial versus neuronal fate choice, and its perdurance triggers excessive gliogenesis, showing that its tight and dynamic regulation ensures the proper balance between neurons and glia. Here, we present a genetic screen for potential gcm/glide interactors and identify genes encoding chromatin factors of the Trithorax and of the Polycomb groups. These proteins maintain the heritable epigenetic state, among others, of HOX genes throughout development, but their regulatory role on transiently expressed genes remains elusive. Here we show that Polycomb negatively affects Gcm/Glide autoregulation, a positive feedback loop that allows timely accumulation of Gcm/Glide threshold levels. Such temporal fine-tuning of gene expression tightly controls gliogenesis. This work performed at the levels of individual cells reveals an undescribed mode of Polycomb action in the modulation of transiently expressed fate determinants and hence in the acquisition of specific cell identity in the nervous system. PMID:23300465

  11. Investigations of Lateral Stability of a Glide Bomb Using Automatic Control Having No Time Lag

    NASA Technical Reports Server (NTRS)

    Sponder, E. W.

    1950-01-01

    The investigation of the lateral stability of an automatically controlled glide bomb led also to the attempt of clarifying the influence of a phugoid oscillation or of any general longitudinal oscillation on the lateral stability of a glide bomb. Under the assumption that its period of oscillation considerably exceeds the rolling and yawing oscillation and that c(sub a) is, at least in sections, practically constant, the result of this test is quite simple. It becomes clear that the influence of the phugoid oscillation may be replaced by suitable variation of the rolling-yawing moment on a rectilinear flight path instead of the phugoid oscillation. If the flying weight of the glide bomb of unchanged dimensions is increased, an increase of the flight velocity will be more favorable than an increase of the lift coefficient. The arrangement of the control permits lateral stability to be achieved in every case; a minimum rolling moment due to sideslip proves of great help.

  12. The collapse of stacking fault tetrahedra by interactions with gliding dislocations.

    SciTech Connect

    Matsukawa, Yoshitaka; Osetskiy, Yury N; Stocks, George Malcolm; Zinkle, Steven J

    2005-01-01

    The collapse of stacking-fault tetrahedra (SFT) by gliding dislocations was observed in in situ straining experiments in a transmission electron microscope (TEM). A stacking-fault tetrahedron was collapsed by intersection with a gliding perfect dislocation: only the base portion divided by the gliding plane of the dislocation annihilated, while the apex portion remained intact. As a result of analysis on evolution of atom configuration induced by intersection with perfect dislocation in SFT, it was found that an unusual atom configuration inevitably appeared in one of the ledges formed on stacking-fault planes, which is traditionally called I-ledge: the atoms on adjacent (111) planes were overlapping each other. The overlapping configuration provides a strong repulsive force, being a conceivable driving force to induce a chain reaction of atom displacements that collapses the SFT base portion.

  13. A quantitative evaluation of the dynamic cathodoluminescence contrast of gliding dislocations in semiconductor crystals

    NASA Astrophysics Data System (ADS)

    Vasnyov, S.; Schreiber, J.; Hoering, L.

    2004-01-01

    Dark cathodoluminescence (CL) defect contrasts observed in CL video movies taken on GaAs and ZnO samples disclose the intrinsic recombination properties of glide dislocations during their slip motion. This way, the kinematical SEM CL microscopy provides, for the first time, direct information on the possible relationship between the dynamics and electronic activity of glide dislocations as expected from structural alterations or kink processes related to defect movement. The dark CL defect contrasts observed for various dislocation types in both materials indicate defect-bound non-radiative excess carrier recombination. Quantitative CL contrast analysis is performed to discover differences in the recombination strength of distinct dislocation structures resulting from the type and dynamic state of the glide dislocations studied.

  14. Extended survival times of Mycoplasma gallisepticum and Mycoplasma synoviae on kanekalon synthetic hair fibres.

    PubMed

    Abolnik, Celia; Gouws, Johan

    2014-01-01

    The survival times of Mycoplasma gallisepticum (Mg) and Mycoplasma synoviae (Ms) on washed and unwashed natural and synthetic kanekalon hair samples over a 5-d period were evaluated using the color changing unit method for comparison with results of previous studies conducted on natural hair. Regardless of whether synthetic or natural hair samples prewashed with a disinfectant shampoo were spiked with Mg or Ms, all viable organisms rapidly dropped below a count of 1 × 10(1)/mL of culture. Unwashed natural hair seeded with a titer of approximately 1 × 10(6)/mL of viable Mg or Ms decreased to 6 × 10(5)/mL and 6 × 10(3)/mL, respectively, by 4 h postseeding, but no viable Mg or Ms were detected on natural hair from 8 h onwards. By contrast, the titers of Mg and Ms on synthetic hair did not decline from the initial 1 × 10(6)/mL seed dose up to 96 h postseeding, and, in fact, viable Mg and Ms was still detectable at 9 d postinfection. Application of a real-time quantitative single-tube duplex PCR assay confirmed that no proliferation of Mg or Ms had occurred on the synthetic hair samples, the cells simply remained viable. The unexpected finding that Mg and Ms survive for extended periods on synthetic kanekalon hair fibers raises the question of whether attachment to a surface is a prerequisite for the survival and persistence of Mg and Ms in the extra-host environment. Future studies should be aimed at determining whether other synthetic hair types or indeed other types of plastics commonly found in the poultry house offer similar survival advantages to mycoplasmas. PMID:24570416

  15. Cruising the rain forest floor: butterfly wing shape evolution and gliding in ground effect.

    PubMed

    Cespedes, Ann; Penz, Carla M; DeVries, Philip J

    2015-05-01

    Flight is a key innovation in the evolutionary success of insects and essential to dispersal, territoriality, courtship and oviposition. Wing shape influences flight performance and selection likely acts to maximize performance for conducting essential behaviours that in turn results in the evolution of wing shape. As wing shape also contributes to fitness, optimal shapes for particular flight behaviours can be assessed with aerodynamic predictions and placed in an ecomorphological context. Butterflies in the tribe Haeterini (Nymphalidae) are conspicuous members of understorey faunas in lowland Neotropical forests. Field observations indicate that the five genera in this clade differ in flight height and behaviour: four use gliding flight at the forest floor level, and one utilizes flapping flight above the forest floor. Nonetheless, the association of ground level gliding flight behaviour and wing shape has never been investigated in this or any other butterfly group. We used landmark-based geometric morphometrics to test whether wing shapes in Haeterini and their close relatives reflected observed flight behaviours. Four genera of Haeterini and some distantly related Satyrinae showed significant correspondence between wing shape and theoretical expectations in performance trade-offs that we attribute to selection for gliding in ground effect. Forewing shape differed between sexes for all taxa, and male wing shapes were aerodynamically more efficient for gliding flight than corresponding females. This suggests selection acts differentially on male and female wing shapes, reinforcing the idea that sex-specific flight behaviours contribute to the evolution of sexual dimorphism. Our study indicates that wing shapes in Haeterini butterflies evolved in response to habitat-specific flight behaviours, namely gliding in ground effect along the forest floor, resulting in ecomorphological partitions of taxa in morphospace. The convergent flight behaviour and wing morphology

  16. Tensile response of passivated films with climb-assisted dislocation glide

    NASA Astrophysics Data System (ADS)

    Ayas, C.; Deshpande, V. S.; Geers, M. G. D.

    2012-09-01

    The tensile response of single crystal films passivated on two sides is analysed using climb enabled discrete dislocation plasticity. Plastic deformation is modelled through the motion of edge dislocations in an elastic solid with a lattice resistance to dislocation motion, dislocation nucleation, dislocation interaction with obstacles and dislocation annihilation incorporated through a set of constitutive rules. The dislocation motion in the films is by glide-only or by climb-assisted glide whereas in the surface passivation layers dislocation motion occurs by glide-only and penalized by a friction stress. For realistic values of the friction stress, the size dependence of the flow strength of the oxidised films was mainly a geometrical effect resulting from the fact that the ratio of the oxide layer thickness to film thickness increases with decreasing film thickness. However, if the passivation layer was modelled as impenetrable, i.e. an infinite friction stress, the plastic hardening rate of the films increases with decreasing film thickness even for geometrically self-similar specimens. This size dependence is an intrinsic material size effect that occurs because the dislocation pile-up lengths become on the order of the film thickness. Counter-intuitively, the films have a higher flow strength when dislocation motion is driven by climb-assisted glide compared to the case when dislocation motion is glide-only. This occurs because dislocation climb breaks up the dislocation pile-ups that aid dislocations to penetrate the passivation layers. The results also show that the Bauschinger effect in passivated thin films is stronger when dislocation motion is climb-assisted compared to films wherein dislocation motion is by glide-only.

  17. Aerodynamic performance due to forewing and hindwing interaction in gliding dragonfly flight

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Lu, Xi-Yun

    2009-07-01

    Aerodynamic performance due to forewing and hindwing interaction in gliding dragonfly flight has been studied using a multiblock lattice Boltzmann method. We find that the interactions between forewing and hindwing effectively enhance the total lift force and reduce the drag force on the wings compared to two independent wings. The interaction mechanism may be associated with the triangular camber effect by modulating the relative arrangement of the forewing and hindwing. The results obtained in this Brief Report provide physical insight into the understanding of aerodynamic behaviors for gliding dragonfly flight.

  18. The Role of Incision and Sedimentation in Continental Gravity Gliding - Insight from Numerical Modelling

    NASA Astrophysics Data System (ADS)

    Riad, H.; Messager, G.; Nivihre, B.

    2010-12-01

    Large scale gravity gliding are usually observed in deltas and passive margins. They imply the rigid translation of a body down a slope, with coeval upslope extension and downslope contraction. Displacement vectors are parallel to a buried detachment plane gently dipping basinward (1-5°). Field examples suggest that gravity gliding could be found in continental domains but contrary to oceanic environments, upslope sedimentation and pore fluid overpressure do not play a major role. These lacks must be compensated. This study investigates mechanisms generating gravity gliding in a continental domains through the use of a two-dimensional (2D) finite-element model and a 2D analytical failure analysis. We focus on the role of tectonic uplifts and the subsequent fluvial incision and sedimentation at the toes of the slopes. The geometries of the numerical models are based on a field example in the Andean foothills of Argentina. Gravity gliding occurs along the long limb of an asymmetric crustal-scale anticline, above a 1000 m depth salt layers. The numerical models simulate the deformations and estimate quantitatively the circumstances under which failure at the head and toe of the frictional-plastic sedimentary cover initiates. Analytical solutions give simplified approximation of the numerical results taking into account many configurations with various values of the incision, sedimentation, internal friction angle and thickness of the décollement layer. The principal effect of the incision and sedimentation is to reduce and strengthen the downslope resistance to the contractional failure. Consequently, the magnitude of the critical slope for which the gravity gliding initiates, is reduced by the incision and is increased by the sedimentation. Results show that large-scale gravity gliding can be found in continental domains as a consequence of tectonic uplifts and where overburden thickness is lower than 2000 m. Incision facilitates and localizes the gliding

  19. The in vitro effect of six antimicrobials against Mycoplasma putrefaciens, Mycoplasma mycoides subsp. mycoides LC and Mycoplasma capricolum subsp. capricolum isolated from sheep and goats in Jordan.

    PubMed

    Al-Momani, W; Nicholas, R A J; Janakat, S; Abu-Basha, E; Ayling, R D

    2006-01-01

    Respiratory disease in sheep and goats is a major problem in Jordan and is often associated with Mycoplasma species. Without effective vaccines, control is mainly by chemotherapy, but the uncontrolled use of antimicrobials has led to concerns about the potential development of antimicrobial resistance. The in vitro effect of chloramphenicol, florfenicol, enrofloxacin, tylosin, erythromycin and oxytetracycline was determined against 32 isolates of Mycoplasma species-M. mycoides subsp. mycoides LC (6), M. capricolum subsp. capricolum (8) and M. putrefaciens (18), all isolated from either nasal swabs or milk, from sheep and goats in different regions of Jordan. The antimicrobial susceptibility showed some Mycoplasma species-specific differences, with M. capricolum subsp. capricolum being more susceptible to tylosin and erythromycin. Chloramphenicol and florfenicol were the least effective for all three Mycoplasma species. No trends or significant differences in antimicrobial susceptibilities were observed between sheep and goat isolates, between milk or nasal swab isolates, or between isolates from different regions of Jordan. Some isolates of M. capricolum subsp. capricolum and M. putrefaciens showed higher MIC levels with oxytetracycline, as did two isolates of M. mycoides subsp. mycoides LC with tylosin, possibly indicating signs of development of antimicrobial resistance. PMID:17405622

  20. Gliding Text: A New Aid to Improve the Reading Performance of Poor Readers by Subconscious Gaze Control.

    ERIC Educational Resources Information Center

    Krischer, C. C.; And Others

    1994-01-01

    People with reading difficulties experience automatic gaze guidance when using gliding text (subtitles). Reading exercises with gliding text eliminated reading difficulties for 21 second graders in 24 15-minute sessions. Mean reading speed increased from 10 to 24 words per minute. (SK)

  1. Mycoplasma mycoides, from "mycoides Small Colony" to "capri". A microevolutionary perspective

    PubMed Central

    2011-01-01

    Background The Mycoplasma mycoides cluster consists of five species or subspecies that are ruminant pathogens. One subspecies, Mycoplasma mycoides subspecies mycoides Small Colony (MmmSC), is the causative agent of contagious bovine pleuropneumonia. Its very close relative, Mycoplasma mycoides subsp. capri (Mmc), is a more ubiquitous pathogen in small ruminants causing mastitis, arthritis, keratitis, pneumonia and septicaemia and is also found as saprophyte in the ear canal. To understand the genetics underlying these phenotypic differences, we compared the MmmSC PG1 type strain genome, which was already available, with the genome of an Mmc field strain (95010) that was sequenced in this study. We also compared the 95010 genome with the recently published genome of another Mmc strain (GM12) to evaluate Mmc strain diversity. Results The MmmSC PG1 genome is 1,212 kbp and that of Mmc 95010 is ca. 58 kbp shorter. Most of the sequences present in PG1 but not 95010 are highly repeated Insertion Sequences (three types of IS) and large duplicated DNA fragments. The 95010 genome contains five types of IS, present in fewer copies than in PG1, and two copies of an integrative conjugative element. These mobile genetic elements have played a key role in genome plasticity, leading to inversions of large DNA fragments. Comparison of the two genomes suggested a marked decay of the PG1 genome that seems to be correlated with a greater number of IS. The repertoire of gene families encoding surface proteins is smaller in PG1. Several genes involved in polysaccharide metabolism and protein degradation are also absent from, or degraded in, PG1. Conclusions The genome of MmmSC PG1 is larger than that of Mmc 95010, its very close relative, but has less coding capacity. This is the result of large genetic rearrangements due to mobile elements that have also led to marked gene decay. This is consistent with a non-adaptative genomic complexity theory, allowing duplications or pseudogenes to

  2. Metabolomics reveals mycoplasma contamination interferes with the metabolism of PANC-1 cells.

    PubMed

    Yu, Tao; Wang, Yongtao; Zhang, Huizhen; Johnson, Caroline H; Jiang, Yiming; Li, Xiangjun; Wu, Zeming; Liu, Tian; Krausz, Kristopher W; Yu, Aiming; Gonzalez, Frank J; Huang, Min; Bi, Huichang

    2016-06-01

    Mycoplasma contamination is a common problem in cell culture and can alter cellular functions. Since cell metabolism is either directly or indirectly involved in every aspect of cell function, it is important to detect changes to the cellular metabolome after mycoplasma infection. In this study, liquid chromatography mass spectrometry (LC/MS)-based metabolomics was used to investigate the effect of mycoplasma contamination on the cellular metabolism of human pancreatic carcinoma cells (PANC-1). Multivariate analysis demonstrated that mycoplasma contamination induced significant metabolic changes in PANC-1 cells. Twenty-three metabolites were identified and found to be involved in arginine and purine metabolism and energy supply. This study demonstrates that mycoplasma contamination significantly alters cellular metabolite levels, confirming the compelling need for routine checking of cell cultures for mycoplasma contamination, particularly when used for metabolomics studies. Graphical abstract Metabolomics reveals mycoplasma contamination changes the metabolome of PANC-1 cells. PMID:27074779

  3. [Study of Mycoplasma from the genital apparatus of cattle].

    PubMed

    Savov, N; Buchvarova, Ia

    1976-01-01

    The study on vaginal mucous secretion in cows with metritis and vaginitis, on fetuses and placentae of cows that had miscarried as well as on preputial secretion of bulls revealed the presence of Mycoplasma organisms associated with V. fetus and other bacterial species. By their reaction to cholesterol, digitonin, sodium polyanetol sulfonate as well as their serum and temperature requirements, the formation of films and spots, their phosphatase activity and biochemical and serologic behaviour the mycoplasmas isolated from the genital tract of cows were specified as A. laidlawii and A. axanthum. From both cows and bulls T-forms of mycoplasmas were isolated. The strains determined as A. laidlawi showed deviations from the species characteristics by the fermentation of glucose, hydrolysis of esculine, and reduction of 2,3,5-triphenyl-tetrazolium chloride. PMID:960549

  4. Membrane proteins of Mycoplasma bovis and their role in pathogenesis.

    PubMed

    Adamu, James Y; Wawegama, Nadeeka K; Browning, Glenn F; Markham, Philip F

    2013-10-01

    Mycoplasma membrane proteins influence cell shape, cell division, motility and adhesion to host cells, and are thought to be integrally involved in the pathogenesis of mycoplasmoses. Many of the membrane proteins predicted from mycoplasma genome sequences remain hypothetical, as their presence in cellular protein preparations is yet to be established experimentally. Recent genome sequences of several strains of Mycoplasma bovis have provided further insight into the potential role of the membrane proteins of this pathogen in colonisation and infection. This review highlights recent advances in knowledge about the influence of M. bovis membrane proteins on the pathogenesis of infection with this species and identifies future research directions for enhancing our understanding of the role of these proteins. PMID:23810376

  5. Mycoplasma, Ureaplasma, and Adverse Pregnancy Outcomes: A Fresh Look

    PubMed Central

    Larsen, Bryan; Hwang, Joseph

    2010-01-01

    Recent work on the Molicutes that associate with genital tract tissues focuses on four species that may be of interest in potential maternal, fetal, and neonatal infection and in contributing to adverse pregnancy outcomes. Mycoplasma hominis and Ureaplasma urealyticum have historically been the subject of attention, but Mycoplasma genitalis which causes male urethritis in addition to colonizing the female genital tract and the division of Ureaplasma into two species, urealyticum and parvum, has also added new taxonomic clarity. The role of these genital tract inhabitants in infection during pregnancy and their ability to invade and infect placental and fetal tissue is discussed. In particular, the role of some of these organisms in prematurity may be mechanistically related to their ability to induce inflammatory cytokines, thereby triggering pathways leading to preterm labor. A review of this intensifying exploration of the mycoplasmas in relation to pregnancy yields several questions which will be important to examine in future research. PMID:20706675

  6. "Candidatus Mycoplasma haemominutum" infections in 21 client-owned cats.

    PubMed

    Reynolds, Caryn Alice; Lappin, Michael R

    2007-01-01

    Medical records were reviewed for 21 clinically ill cats testing positive for deoxyribonucleic acid (DNA) of "Candidatus Mycoplasma haemominutum" in their blood. Fever, anorexia, lethargy, and anemia were among the most common abnormalities recorded. Thirteen cats were anemic; seven had evidence of other diseases that could have been the primary cause of anemia or activated hemoplasmosis. For six cats, "Candidatus Mycoplasma haemominutum" was the only recognizable cause of the anemia. Of these cats, anemia resolved in one cat without treatment and in three cats that were treated with doxycycline, with or without prednisone. Results of the study suggest that this hemoplasma species can be a primary pathogen in cats. PMID:17823473

  7. Erosive polyarthritis associated with Mycoplasma gateae in a cat.

    PubMed

    Zeugswetter, Florian; Hittmair, Katharina M; de Arespacochaga, Abigail G; Shibly, Sarina; Spergser, Joachim

    2007-06-01

    Erosive polyarthritis was diagnosed in an 11-month-old neutered male Egyptian Mau-cross cat with concurrent glucocorticoid-responsive dermatitis. Clinical signs, synovial fluid analysis, serological tests and radiographic appearance could not differentiate between immune-mediated and infective arthritis. Mycoplasma gateae was isolated by strictly anaerobic culture of the synovial fluid. Treatment with Enrofloxacin led to a rapid improvement of the cat's condition. Two months later the cat was euthanased because of severe glomerulonephritis and direct Coombs' test positive anaemia, possibly caused by mycoplasma infection. M gateae could not be isolated at post-mortem examination. PMID:17175189

  8. Mycoplasma pneumoniae infection and Tourette's syndrome.

    PubMed

    Müller, Norbert; Riedel, Michael; Blendinger, Christa; Oberle, Karin; Jacobs, Enno; Abele-Horn, Marianne

    2004-12-15

    An association between infection and Tourette's syndrome (TS) has been described repeatedly. A role for streptococcal infection (PANDAS) has been established for several years, but the involvement of other infectious agents such as Borrelia Burgdorferi or Mycoplasma pneumoniae has only been described in single case reports. We examined antibody titers against M. pneumoniae and various types of antibodies by immunoblot in patients and in a sex- and age-matched comparison group. Participants comprised 29 TS patients and 29 controls. Antibody titers against M. pneumoniae were determined by microparticle agglutination (MAG) assay and confirmed by immunoblot. Elevated titers were found in significantly more TS patients than controls (17 vs. 1). Additionally, the number of IgA positive patients was significantly higher in the TS group than in the control group (9 vs. 1). A higher proportion of increased serum titers and especially of IgA antibodies suggests a role for M. pneumoniae in a subgroup of patients with TS and supports the finding of case reports implicating an acute or chronic infection with M. pneumoniae as one etiological agent for tics. An autoimmune reaction, however, has to be taken into account. In predisposed persons, infection with various agents including M. pneumoniae should be considered as at least an aggravating factor in TS. PMID:15590039

  9. Mycoplasma Pneumoniae Infection with Neurologic Complications

    PubMed Central

    Yimenicioğlu, Sevgi; Yakut, Ayten; Ekici, Arzu; Bora Carman, Kursat; Cagrı Dinleyici, Ener

    2014-01-01

    Background: Extrapulmonary complications of Mycoplasma pneumoniae (M. pneumoniae) infection include encephalitis, optic neuritis, acute psychosis, stroke, cranial nerve palsies, aseptic meningitis and also it may be implicated in immune mediated neurological diseases such as acute demyelinating encephalomyelitis, Guillain-Barre syndrome and transverse myelitis. Case Presentation: We present five cases with acute neurological diseases after M. pneumoniae infection. The clinical presentations were characterized by encephalitis in 2 patients, Gullain-Barre syndrome in 2 patients, transverse myelitis in 1 patient. M. pneumoniae infection was detected in serum by serological method. Only two patients had respiratory symptoms preceding M. pneumoniae infection. Brain MRI revealed hyperintensities on corpus striatum and mesencephalon in one patient with encephalitis, the other had front parietal coalescent periventricular white matter lesions on T2 images. The patient with transverse myelitis had cervical, dorsal and lumbar scattered hyperintense lesions on T2 images. Two patients were treated with high dose steroid, the other two patients received treatment with intravenous immune globuline. Conclusion: M. pneumoniae may reveal different neurologic complications with different radiologic findings. PMID:25793076

  10. Mechanisms of volume regulation in Mycoplasma gallisepticum

    SciTech Connect

    Linker, C.S.

    1987-01-01

    Mycoplasma gallisepticum, a cell wall-less bacterium, must confront the problem of colloid osmotic swelling. Cell volume was determined by optical density and intracellular water measurements. Transmembrane pH and electrical gradients were determined by the distribution of the weak acid benzoate and lipophilic cation tetraphenylphosphonium respectively. Cells incubated in sodium chloride without glucose exhibited a progressive fall in ATP over several hours. When ATP fell below 40 uM the cells swelled, leaked protein and became permeable to inulin. Subsequent addition of glucose induced shrinkage and restored the original permeability properties. Energized cells exhibited an electrochemical gradient of protons of up to 130 mV, inside negative and alkaline. The proton-ATPase inhibitor dicyclohexylcarbodiimide (DCCD), which collapsed the chemical and electrical components of the proton gradient, induced rapid swelling despite high ATP levels thus implicating the proton gradient in volume regulation. Either the pH gradient or the membrane potential could maintain volume. Energy-dependent sodium efflux in exchange for protons was demonstrated in sodium-loaded cells using radioactive sodium and 9-aminoacridine fluorescence to follow sodium and proton translocation respectively.

  11. Mycoplasma genitalium: An Emerging Sexually Transmitted Infection

    PubMed Central

    Munoz, Jessian L.

    2016-01-01

    Mycoplasma genitalium has been recognized as a cause of male urethritis, and there is now evidence suggesting that it causes cervicitis and pelvic inflammatory disease in women. M. genitalium is a slow growing organism, and, with the advent of nucleic acid amplification test (NAAT), more studies are being performed, and knowledge about the pathogenicity of this organism elucidated. With NAAT detection, treatment modalities have been studied, and the next challenge is to determine the most effective antimicrobial therapy. Doxycycline, the first-line antibiotic for urethritis, is largely ineffective in the treatment of M. genitalium and furthermore, resistance to macrolide has also emerged. The most effective drug is Moxifloxacin although there are emerging reports of resistance to it in various parts of the world. This paper not only highlights the current research and knowledge, but also reviews the diversity of health implications on the health of men and women infected with M. genitalium. Alternate antibiotics and the impact of M. genitalium on infertility are areas that require more studies as we continue to research into this microorganism. PMID:27034904

  12. Temporal evolution characteristics of an annular-mode gliding arc discharge in a vortex flow

    SciTech Connect

    Zhao, Tian-Liang; Liu, Jing-Lin; Li, Xiao-Song; Liu, Jin-Bao; Song, Yuan-Hong; Xu, Yong; Zhu, Ai-Min

    2014-05-15

    An annular-mode gliding arc discharge powered by a 50 Hz alternating current (ac) supply was studied in a vortex flow of dry and humid air. Its temporal evolution characteristics were investigated by electrical measurement, temporally resolved imaging, and temporally resolved optical emission spectroscopic measurements. Three discharge stages of arc-ignition, arc-gliding, and arc-extinction were clearly observed in each half-cycle of the discharge. During the arc-gliding stage, the intensity of light emission from the arc root at the cathode was remarkably higher than that at other areas. The spectral intensity of N{sub 2}(C{sup 3}Π{sub u}−B{sup 3}Π{sub g}) during the arc-ignition stage was much higher than that during the arc-gliding stage, which was contrary to the temporal evolutions of spectral intensities for N{sub 2}{sup +}(B{sup 2}Σ{sub u}{sup +}−X{sup 2}Σ{sub g}{sup +}) and OH(A{sup 2}Σ{sup +}−X{sup 2}Π{sub i}). Temporally resolved vibrational and rotational temperatures of N{sub 2} were also presented and decreased with increasing the water vapor content.

  13. An In Vitro Comparison of Root Canal Transportation by Reciproc File With and Without Glide Path

    PubMed Central

    Nazarimoghadam, Kiumars; Daryaeian, Mohammad; Ramazani, Nahid

    2014-01-01

    Objective: The aim of ideal canal preparation is to prevent iatrogenic aberrations such as transportation. The aim of this study was to evaluate the root canal transportation by Reciproc file with and without glide path. Materials and Methods: Thirty acrylic-resin blocks with a curvature of 60° and size#10 (2% taper) were assigned into two groups (n= 15). In group 1, the glide path was performed using stainless steel k-files size#10 and 15 at working length In group 2, canals were prepared with Reciproc file system at working length. By using digital imaging software (AutoCAD 2008), the pre-instrumentation and post-instrumentation digital images were superimposed over, taking the landmarks as reference points. Then the radius of the internal and external curve of the specimens was calculated at three α, β and γ points (1mm to apex as α, 3mm to apex as β, and 5mm to apex as γ). The data were statically analyzed using the independent T-test and Mann-Whitney U test by SPSS version 16. Results: Glide path was found significant for only external curve in the apical third of the canal; that is, 5mm to apex (P=0.005). But in the other third, canal modification was not significant (P> 0.008). Conclusion: Canal transportation in the apical third of the canal seems to be significantly reduced when glide path is performed using reciprocating files. PMID:25628682

  14. Evaluation of the GlideScope Direct: A New Video Laryngoscope for Teaching Direct Laryngoscopy

    PubMed Central

    Viernes, Darwin; Goldman, Allan J.; Galgon, Richard E.; Joffe, Aaron M.

    2012-01-01

    Background. Teaching direct laryngoscopy is limited by the inability of the instructor to simultaneously view the airway with the laryngoscopist. Our primary aim is to report our initial use of the GlideScope Direct, a video-enabled, Macintosh laryngoscope intended primarily as a training tool in direct laryngoscopy. Methods. The GlideScope Direct was made available to anyone who planned on performing direct laryngoscopy as the primary technique for intubation. Novices were those who had performed <30 intubations. Results. The GlideScope Direct was used 123 times as primarily a direct laryngoscope while the instructor viewed the intubation on the monitor. It was highly successful as a direct laryngoscope (93% success). Salvage by indirect laryngoscopy occurred in 7/9 remaining patients without changing equipment. Novices performed 28 intubations (overall success rate of 79%). In 6 patients, the instructor took over and successfully intubated the patient. Instructors used the video images to guide the operator in 16 (57%) of those patients. Seven different instructors supervised the 28 novices, all of who subjectively felt advantaged by having the laryngoscopic view available. Conclusions. The GlideScope Direct functions similarly to a Macintosh laryngoscope and provides the instructor subjective reassurance, while providing the ability to guide the trainee laryngoscopist. PMID:22778728

  15. Use of glide-ins in CMS for production and analysis

    NASA Astrophysics Data System (ADS)

    Bradley, D.; Gutsche, O.; Hahn, K.; Holzman, B.; Padhi, S.; Pi, H.; Spiga, D.; Sfiligoi, I.; Vaandering, E.; Würthwein, F.; CMS Offline Computing Projects

    2010-04-01

    With the evolution of various grid federations, the Condor glide-ins represent a key feature in providing a homogeneous pool of resources using late-binding technology. The CMS collaboration uses the glide-in based Workload Management System, glideinWMS, for production (ProdAgent) and distributed analysis (CRAB) of the data. The Condor glide-in daemons traverse to the worker nodes, submitted via Condor-G. Once activated, they preserve the Master-Worker relationships, with the worker first validating the execution environment on the worker node before pulling the jobs sequentially until the expiry of their lifetimes. The combination of late-binding and validation significantly reduces the overall failure rate visible to CMS physicists. We discuss the extensive use of the glideinWMS since the computing challenge, CCRC-08, in order to prepare for the forthcoming LHC data-taking period. The key features essential to the success of large-scale production and analysis on CMS resources across major grid federations, including EGEE, OSG and NorduGrid are outlined. Use of glide-ins via the CRAB server mechanism and ProdAgent, as well as first hand experience of using the next generation CREAM computing element within the CMS framework is discussed.

  16. Flavobacterium columnare type IX secretion system mutations result in defects in gliding motility and virulence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: The gliding bacterium Flavobacterium columnare causes columnaris disease in wild and aquaculture-reared freshwater fish. The mechanisms responsible for columnaris disease are not known. The related bacterium Flavobacterium johnsoniae uses a type IX secretion system (T9SS) to secrete enzy...

  17. Use of glide-ins in CMS for production and analysis

    SciTech Connect

    Bradley, D.; Gutsche, O.; Hahn, K.; Holzman, B.; Padhi, S.; Pi, H.; Spiga, D.; Sfiligoi, I.; Vaandering, E.; Wurthwein, F.; /UC, San Diego

    2010-01-01

    With the evolution of various grid federations, the Condor glide-ins represent a key feature in providing a homogeneous pool of resources using late-binding technology. The CMS collaboration uses the glide-in based Workload Management System, glideinWMS, for production (ProdAgent) and distributed analysis (CRAB) of the data. The Condor glide-in daemons traverse to the worker nodes, submitted via Condor-G. Once activated, they preserve the Master-Worker relationships, with the worker first validating the execution environment on the worker node before pulling the jobs sequentially until the expiry of their lifetimes. The combination of late-binding and validation significantly reduces the overall failure rate visible to CMS physicists. We discuss the extensive use of the glideinWMS since the computing challenge, CCRC-08, in order to prepare for the forthcoming LHC data-taking period. The key features essential to the success of large-scale production and analysis on CMS resources across major grid federations, including EGEE, OSG and NorduGrid are outlined. Use of glide-ins via the CRAB server mechanism and ProdAgent, as well as first hand experience of using the next generation CREAM computing element within the CMS framework is discussed.

  18. Experimental studies on the pathogenicity of Mycoplasma ovipneumoniae and Mycoplasma arginini for the respiratory tract of goats.

    PubMed Central

    Goltz, J P; Rosendal, S; McCraw, B M; Ruhnke, H L

    1986-01-01

    Mycoplasma ovipneumoniae and Mycoplasma arginini were the species of Mollicutes most commonly isolated from 175 goats with respiratory disease in Ontario. The pathogenicity of M. ovipneumoniae, strain B321B and M. arginini, strain D53e, was assessed in goats following endobronchial inoculation. One out of three two year old goats developed fever after inoculation with a pure culture of strain B321B, and it had extensive subacute fibrinous pleuritis when necropsied three weeks later. Neither of the remaining goats had lesions in the respiratory tract. Mycoplasma ovipneumoniae was recovered from one of the animals four days after inoculation, but not at necropsy from any of the goats, at which time a marked humoral immune response with growth inhibiting antibodies was detected. In a second experiment three four to five week old goats were inoculated with the same strain and three other goats were given placebo treatment. One experimental goat developed fever and coughing, and it had extensive subacute fibrinous pleuritis in the right side and pneumonia. Another goat had focal pneumonia in the left diaphragmatic lobe. Microscopically there was subacute hyperplastic suppurative bronchiolitis, atelectasis and nonsuppurative alveolitis. The infected animals did not clear the mycoplasma and not all of them produced antibodies. Mycoplasma arginini, strain D53e, did not induce lesions in any of four goat kids within 14 days after inoculation but did cause transient elevations in rectal temperature, circulating monocytes, circulating neutrophils and blood fibrinogen. Mycoplasma arginini was infective and immunogenic for all inoculated animals and showed a particular affinity for the tonsil. Thus, this study provides the first evidence that M. ovipneumoniae is pathogenic for goats causing pneumonia and pleuritis.(ABSTRACT TRUNCATED AT 250 WORDS) Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:3742358

  19. Modeling dislocation glide in Mg2SiO4 ringwoodite: Towards rheology under transition zone conditions

    NASA Astrophysics Data System (ADS)

    Ritterbex, S.; Carrez, Ph.; Gouriet, K.; Cordier, P.

    2015-11-01

    Deformation resulting from thermally activated plastic slip is modeled in Mg2SiO4 ringwoodite at 20 GPa for a wide range of temperatures. The model relies on the structures of the rate controlling 1 / 2 < 1 1 0 > screw dislocations which have been modeled using the Peierls-Nabarro-Galerkin method. These calculations are parametrized by density functional theory calculations of γ -surfaces of the { 0 0 1 }, { 1 1 0 } and { 1 1 1 } planes. At finite temperatures, dislocation mobility is controlled by kink-pair nucleation on the thermally activated 1 / 4 < 1 1 0 > partial screw dislocations as they occur in ringwoodite. Single slip critical resolved shear stresses (CRSS) corresponding to this mechanism are deduced from Orowan's equation. The results are found to be in reasonably good agreement with experimental data at 20 GPa which show high effective flow stresses under laboratory conditions. Finally, the CRSS's are calculated for typical mantle strain rates of ɛ ˙ =10-16 s-1 at appropriate temperatures expected in the lower transition zone. Results show that dislocation glide remains difficult and that lattice friction is not yet negligible in ringwoodite under natural conditions.

  20. Differences in torsional performance of single- and multiple-instrument rotary systems for glide path preparation.

    PubMed

    Arias, Ana; Singh, Rupinderpal; Peters, Ove A

    2016-05-01

    A new rotary instrument has been developed to simplify the glide path preparation in root canals before shaping procedures. The purpose of this study was to compare the peak torque and force induced by nickel-titanium PathFile multiple-instrument system and the recently developed M-Wire ProGlider single instrument during glide path preparation of mesial root canals in extracted mandibular molars. Each independent canal of eight mesial roots of mandibular molars was randomly assigned to achieve a reproducible glide path with a new set of either PathFile #1 and #2 or ProGlider after negotiation with a 10 K-file. Tests were run in a standardized fashion using a torque-testing platform. Peak torque (N cm) and force (N) were registered and analysis of variance and Tukey post-hoc tests were applied. Preliminary data for stationary torque at failure were also obtained and compared with peak torque for each instrument. PathFile #1 and #2 instruments showed statistically lower peak torque (p = 0.001) and peak force (p = 0.008) than ProGlider. Torque at failure according to ADA No. 28/ISO 36030-1 was not significantly different from peak torque during glide path preparation for ProGlider instruments while it was significantly higher for PathFile #1 and #2 (p < 0.001). Under the conditions of this study, PathFile instruments developed significant lower peak torque and force during glide path preparation compared to ProGlider, which is possibly subjected to a greater contact with the canal walls due to the increase in its flute diameter at middle and coronal levels. PMID:25701538

  1. The Effect of Depth on Drag During the Streamlined Glide: A Three-Dimensional CFD Analysis

    PubMed Central

    Novais, Maria L.; Silva, António J.; Mantha, Vishveshwar R.; Ramos, Rui J.; Rouboa, Abel I.; Vilas-Boas, J. Paulo; Luís, Sérgio R.; Marinho, Daniel A.

    2012-01-01

    The aim of this study was to analyze the effects of depth on drag during the streamlined glide in swimming using Computational Fluid Dynamics. The Computation Fluid Dynamic analysis consisted of using a three-dimensional mesh of cells that simulates the flow around the considered domain. We used the K-epsilon turbulent model implemented in the commercial code Fluent® and applied it to the flow around a three-dimensional model of an Olympic swimmer. The swimmer was modeled as if he were gliding underwater in a streamlined prone position, with hands overlapping, head between the extended arms, feet together and plantar flexed. Steady-state computational fluid dynamics analyses were performed using the Fluent® code and the drag coefficient and the drag force was calculated for velocities ranging from 1.5 to 2.5 m/s, in increments of 0.50m/s, which represents the velocity range used by club to elite level swimmers during the push-off and glide following a turn. The swimmer model middle line was placed at different water depths between 0 and 1.0 m underwater, in 0.25m increments. Hydrodynamic drag decreased with depth, although after 0.75m values remained almost constant. Water depth seems to have a positive effect on reducing hydrodynamic drag during the gliding. Although increasing depth position could contribute to decrease hydrodynamic drag, this reduction seems to be lower with depth, especially after 0.75 m depth, thus suggesting that possibly performing the underwater gliding more than 0.75 m depth could not be to the benefit of the swimmer. PMID:23487502

  2. Gliding characteristics of flexor tendon and tenosynovium in carpal tunnel syndrome: a pilot study.

    PubMed

    Ettema, Anke M; Zhao, Chunfeng; Amadio, Peter C; O'Byrne, Megan M; An, Kai-Nan

    2007-04-01

    The characteristic pathological finding in carpal tunnel syndrome (CTS) is noninflammatory fibrosis of the synovium. How this fibrosis might affect tendon function, if at all, is unknown. The subsynovial connective tissue (SSCT) lies between the flexor tendons and the visceral synovium (VS) of the ulnar tenosynovial bursa. Fibrosis of the SSCT may well affect its gliding characteristics. To investigate this possibility, the relative motion of the flexor tendon and VS was observed during finger flexion in patients undergoing carpal tunnel surgery, and for comparison in hands without CTS, in an in vitro cadaver model. We used a camera to document the gliding motion of the middle finger flexor digitorum superficialis (FDS III) tendon and SSCT in three patients with CTS during carpal tunnel release and compared this with simulated active flexion in three cadavers with no antemortem history of CTS. The data were digitized with the use of Analyze Software (Biomedical Imaging Resource, Mayo Clinic, Rochester, MN). In the CTS patients, the SSCT moved en bloc with the tendon, whereas, in the controls the SSCT moved smoothly and separately from the tendon. The ratio of VS to tendon motion was higher for the patients than in the cadaver controls. These findings suggest that in patients with CTS the synovial fibrosis has altered the gliding characteristics of the SSCT. The alterations in the gliding characteristics of the SSCT may affect the ability of the tendons in the carpal tunnel to glide independently from each other, or from the nearby median nerve. These abnormal tendon mechanics may play a role in the etiology of CTS. PMID:16944527

  3. Ancient phylogenetic divergence of the enigmatic African rodent Zenkerella and the origin of anomalurid gliding

    PubMed Central

    Fernández, David; Sallam, Hesham M.; Cronin, Drew T.; Esara Echube, José Manuel

    2016-01-01

    The “scaly-tailed squirrels” of the rodent family Anomaluridae have a long evolutionary history in Africa, and are now represented by two gliding genera (Anomalurus and Idiurus) and a rare and obscure genus (Zenkerella) that has never been observed alive by mammalogists. Zenkerella shows no anatomical adaptations for gliding, but has traditionally been grouped with the glider Idiurus on the basis of craniodental similarities, implying that either the Zenkerella lineage lost its gliding adaptations, or that Anomalurus and Idiurus evolved theirs independently. Here we present the first nuclear and mitochondrial DNA sequences of Zenkerella, based on recently recovered whole-body specimens from Bioko Island (Equatorial Guinea), which show unambiguously that Zenkerella is the sister taxon of Anomalurus and Idiurus. These data indicate that gliding likely evolved only once within Anomaluridae, and that there were no subsequent evolutionary reversals. We combine this new molecular evidence with morphological data from living and extinct anomaluromorph rodents and estimate that the lineage leading to Zenkerella has been evolving independently in Africa since the early Eocene, approximately 49 million years ago. Recently discovered fossils further attest to the antiquity of the lineage leading to Zenkerella, which can now be recognized as a classic example of a “living fossil,” about which we know remarkably little. The osteological markers of gliding are estimated to have evolved along the stem lineage of the Anomalurus–Idiurus clade by the early Oligocene, potentially indicating that this adaptation evolved in response to climatic perturbations at the Eocene–Oligocene boundary (∼34 million years ago). PMID:27602286

  4. The Effect of Depth on Drag During the Streamlined Glide: A Three-Dimensional CFD Analysis.

    PubMed

    Novais, Maria L; Silva, António J; Mantha, Vishveshwar R; Ramos, Rui J; Rouboa, Abel I; Vilas-Boas, J Paulo; Luís, Sérgio R; Marinho, Daniel A

    2012-06-01

    The aim of this study was to analyze the effects of depth on drag during the streamlined glide in swimming using Computational Fluid Dynamics. The Computation Fluid Dynamic analysis consisted of using a three-dimensional mesh of cells that simulates the flow around the considered domain. We used the K-epsilon turbulent model implemented in the commercial code Fluent(®) and applied it to the flow around a three-dimensional model of an Olympic swimmer. The swimmer was modeled as if he were gliding underwater in a streamlined prone position, with hands overlapping, head between the extended arms, feet together and plantar flexed. Steady-state computational fluid dynamics analyses were performed using the Fluent(®) code and the drag coefficient and the drag force was calculated for velocities ranging from 1.5 to 2.5 m/s, in increments of 0.50m/s, which represents the velocity range used by club to elite level swimmers during the push-off and glide following a turn. The swimmer model middle line was placed at different water depths between 0 and 1.0 m underwater, in 0.25m increments. Hydrodynamic drag decreased with depth, although after 0.75m values remained almost constant. Water depth seems to have a positive effect on reducing hydrodynamic drag during the gliding. Although increasing depth position could contribute to decrease hydrodynamic drag, this reduction seems to be lower with depth, especially after 0.75 m depth, thus suggesting that possibly performing the underwater gliding more than 0.75 m depth could not be to the benefit of the swimmer. PMID:23487502

  5. Ancient phylogenetic divergence of the enigmatic African rodent Zenkerella and the origin of anomalurid gliding.

    PubMed

    Heritage, Steven; Fernández, David; Sallam, Hesham M; Cronin, Drew T; Esara Echube, José Manuel; Seiffert, Erik R

    2016-01-01

    The "scaly-tailed squirrels" of the rodent family Anomaluridae have a long evolutionary history in Africa, and are now represented by two gliding genera (Anomalurus and Idiurus) and a rare and obscure genus (Zenkerella) that has never been observed alive by mammalogists. Zenkerella shows no anatomical adaptations for gliding, but has traditionally been grouped with the glider Idiurus on the basis of craniodental similarities, implying that either the Zenkerella lineage lost its gliding adaptations, or that Anomalurus and Idiurus evolved theirs independently. Here we present the first nuclear and mitochondrial DNA sequences of Zenkerella, based on recently recovered whole-body specimens from Bioko Island (Equatorial Guinea), which show unambiguously that Zenkerella is the sister taxon of Anomalurus and Idiurus. These data indicate that gliding likely evolved only once within Anomaluridae, and that there were no subsequent evolutionary reversals. We combine this new molecular evidence with morphological data from living and extinct anomaluromorph rodents and estimate that the lineage leading to Zenkerella has been evolving independently in Africa since the early Eocene, approximately 49 million years ago. Recently discovered fossils further attest to the antiquity of the lineage leading to Zenkerella, which can now be recognized as a classic example of a "living fossil," about which we know remarkably little. The osteological markers of gliding are estimated to have evolved along the stem lineage of the Anomalurus-Idiurus clade by the early Oligocene, potentially indicating that this adaptation evolved in response to climatic perturbations at the Eocene-Oligocene boundary (∼34 million years ago). PMID:27602286

  6. Involvement of the Type IX Secretion System in Capnocytophaga ochracea Gliding Motility and Biofilm Formation

    PubMed Central

    Kita, Daichi; Shibata, Satoshi; Kikuchi, Yuichiro; Kokubu, Eitoyo; Nakayama, Koji; Saito, Atsushi

    2016-01-01

    Capnocytophaga ochracea is a Gram-negative, rod-shaped bacterium that demonstrates gliding motility when cultured on solid agar surfaces. C. ochracea possesses the ability to form biofilms; however, factors involved in biofilm formation by this bacterium are unclear. A type IX secretion system (T9SS) in Flavobacterium johnsoniae was shown to be involved in the transport of proteins (e.g., several adhesins) to the cell surface. Genes orthologous to those encoding T9SS proteins in F. johnsoniae have been identified in the genome of C. ochracea; therefore, the T9SS may be involved in biofilm formation by C. ochracea. Here we constructed three ortholog-deficient C. ochracea mutants lacking sprB (which encodes a gliding motility adhesin) or gldK or sprT (which encode T9SS proteins in F. johnsoniae). Gliding motility was lost in each mutant, suggesting that, in C. ochracea, the proteins encoded by sprB, gldK, and sprT are necessary for gliding motility, and SprB is transported to the cell surface by the T9SS. For the ΔgldK, ΔsprT, and ΔsprB strains, the amounts of crystal violet-associated biofilm, relative to wild-type values, were 49%, 34%, and 65%, respectively, at 48 h. Confocal laser scanning and scanning electron microscopy revealed that the biofilms formed by wild-type C. ochracea were denser and bacterial cells were closer together than in those formed by the mutant strains. Together, these results indicate that proteins exported by the T9SS are key elements of the gliding motility and biofilm formation of C. ochracea. PMID:26729712

  7. Molecular epidemiological analysis of Mycoplasma bovis isolates from the Pennsylvania Animal Diagnostic Laboratory showing genetic diversity.

    PubMed

    Soehnlen, M K; Kariyawasam, S; Lumadue, J A; Pierre, T A; Wolfgang, D R; Jayarao, B M

    2011-04-01

    We have examined the genetic variability of Mycoplasma bovis strains submitted to the Pennsylvania Animal Diagnostics Laboratory, University Park (PA-ADL), between December 2007 and December 2008. Of 4,868 total samples submitted for Mycoplasma testing, 302 were determined to be culture positive. Mycoplasma bovis (63.6%), Mycoplasma californicum (7.3%), Mycoplasma bovirhinis (2.7%), Mycoplasma bovigenitalium (0.7%), Mycoplasma alkalescens (4.9%), Mycoplasma putrefaciens (0.3%), and Mycoplasma dispar (1.3%) and unidentified Mycoplasma sp. (19.2%) were identified using PCR. Mycoplasma bovis represented the largest portion of the positive samples submitted. Each of the 192 M. bovis isolates was examined for variations in the BglII and MfeI restriction sites of the DNA using amplified fragment length polymorphism fingerprinting and subsequently compared with the M. bovis type strain PG45 (ATCC 25523). Similarity between strains was calculated using the Dice similarity coefficient, which ranged from approximately 0.7 to 1.0. When clustering the isolates at greater than 95% similarity, it was determined that 11 distinct clusters were present. The results are consistent with the existence of at least 2 clonally distinct groups. No clear geographical, month of isolation, or source origination relationship was identified, indicating that a currently unclassified characteristic is responsible for the strain heterogeneity. These data indicate strong heterogeneity of M. bovis isolates submitted to PA-ADL. Additionally, multiple sites throughout Pennsylvania had isolates of separate clonal lineages present concomitantly, indicating the ability of multiple overlapping outbreaks to occur at a single location. Mycoplasma bovis represents the largest portion of Mycoplasma species isolated from PA-ADL samples. We propose that amplified fragment length polymorphism may serve as a valuable tool for molecular characterization of M. bovis strains from the United States. PMID:21426978

  8. Real-time PCR investigation of potential vectors, reservoirs, and shedding patterns of feline hemotropic mycoplasmas.

    PubMed

    Willi, Barbara; Boretti, Felicitas S; Meli, Marina L; Bernasconi, Marco V; Casati, Simona; Hegglin, Daniel; Puorger, Maria; Neimark, Harold; Cattori, Valentino; Wengi, Nicole; Reusch, Claudia E; Lutz, Hans; Hofmann-Lehmann, Regina

    2007-06-01

    Three hemotropic mycoplasmas have been identified in pet cats: Mycoplasma haemofelis, "Candidatus Mycoplasma haemominutum," and "Candidatus Mycoplasma turicensis." The way in which these agents are transmitted is largely unknown. Thus, this study aimed to investigate fleas, ticks, and rodents as well as saliva and feces from infected cats for the presence of hemotropic mycoplasmas, to gain insight into potential transmission routes for these agents. DNA was extracted from arthropods and from rodent blood or tissue samples from Switzerland and from salivary and fecal swabs from two experimentally infected and six naturally infected cats. All samples were analyzed with real-time PCR, and some positive samples were confirmed by sequencing. Feline hemotropic mycoplasmas were detected in cat fleas and in a few Ixodes sp. and Rhipicephalus sp. ticks collected from animals but not in ticks collected from vegetation or from rodent samples, although the latter were frequently Mycoplasma coccoides PCR positive. When shedding patterns of feline hemotropic mycoplasmas were investigated, "Ca. Mycoplasma turicensis" DNA was detected in saliva and feces at the early but not at the late phase of infection. M. haemofelis and "Ca. Mycoplasma haemominutum" DNA was not amplified from saliva and feces of naturally infected cats, despite high hemotropic mycoplasma blood loads. Our results suggest that besides an ostensibly indirect transmission by fleas, direct transmission through saliva and feces at the early phase of infection could play a role in the epizootiology of feline hemotropic mycoplasmas. Neither the investigated tick nor the rodent population seems to represent a major reservoir for feline hemotropic mycoplasmas in Switzerland. PMID:17468284

  9. The effect of sustained natural apophyseal glide (SNAG) combined with neurodynamics in the management of a patient with cervical radiculopathy: a case report.

    PubMed

    Anandkumar, Sudarshan

    2015-02-01

    This case report describes a 47-year-old female who presented with complaints of pain in the right elbow radiating down to the thumb. Physical examination revealed symptom reproduction with Spurling A test, upper limb neurodynamic testing-1 and right cervical rotation along with reduced symptoms with neck distraction. Clinical diagnosis of cervical radiculopathy (CR) was made based on a clinical prediction rule. This case report speculates a potentially first-time description of successful conservative management of CR in a patient utilizing simultaneous combination of sustained natural apophyseal glide and neurodynamic mobilization. Immediate improvements were seen in pain, cervical range of motion and functional abilities. The patient was discharged from physical therapy by the second week after four treatment sessions with complete pain resolution maintained at a four-month follow-up period. PMID:25329587

  10. Macrolide-Resistant Mycoplasma pneumoniae, United States1

    PubMed Central

    Lee, Stella; Selvarangan, Rangaraj; Qin, Xuan; Tang, Yi-Wei; Stiles, Jeffrey; Hong, Tao; Todd, Kathleen; Ratliff, Amy E.; Crabb, Donna M.; Xiao, Li; Atkinson, T. Prescott; Waites, Ken B.

    2015-01-01

    Macrolide-resistant Mycoplasma pneumoniae (MRMP) is highly prevalent in Asia and is now being reported from Europe. Few data on MRMP are available in the United States. Using genotypic and phenotypic methods, we detected high-level MRMP in 13.2% of 91 M. pneumoniae­–positive specimens from 6 US locations. PMID:26196107

  11. Complete Genome Sequence of Mycoplasma synoviae Strain WVU 1853T

    PubMed Central

    Kutish, Gerald F.; Barbet, Anthony F.; Michaels, Dina L.

    2015-01-01

    A hybrid sequence assembly of the complete Mycoplasma synoviae type strain WVU 1853T genome was compared to that of strain MS53. The findings support prior conclusions about M. synoviae, based on the genome of that otherwise uncharacterized field strain, and provide the first evidence of epigenetic modifications in M. synoviae. PMID:26021934

  12. Genome Sequence of a Mycoplasma meleagridis Field Strain.

    PubMed

    Rocha, Ticiana S; Bertolotti, Luigi; Catania, Salvatore; Pourquier, Philippe; Rosati, Sergio

    2016-01-01

    Mycoplasma meleagridis is a major cause of disease and economic loss in turkeys. Here, we report the genome sequence of an M. meleagridis field strain, which enlarges the knowledge about this bacterium and helps the identification of possible coding sequences for drug resistance genes and specific antigens. PMID:26941131

  13. 9 CFR 113.28 - Detection of mycoplasma contamination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... REQUIREMENTS Standard Procedures § 113.28 Detection of mycoplasma contamination. The heart infusion test, using heart infusion broth and heart infusion agar, provided in this section shall be conducted when a test... inactivated at 56 °C for 30 minutes. (b) Heart infusion broth shall be prepared as provided in this...

  14. 9 CFR 113.28 - Detection of mycoplasma contamination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... REQUIREMENTS Standard Procedures § 113.28 Detection of mycoplasma contamination. The heart infusion test, using heart infusion broth and heart infusion agar, provided in this section shall be conducted when a test... inactivated at 56 °C for 30 minutes. (b) Heart infusion broth shall be prepared as provided in this...

  15. Innate Immune Response to Intramammary Mycoplasma bovis Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mastitis caused by Mycoplasma bovis is a growing concern for the dairy industry. M. bovis intramammary infection commonly results in an untreatable case of chronic mastitis. The innate immune system is responsible for initial recognition of, and immediate host responses to, infectious pathogens. ...

  16. Stability of rehydrated Mycoplasma gallisepticum vaccine homogeneity over time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proper vaccine application is required to maximize the results of the vaccination, with maintenance of a homogenous solution is critical to obtain uniform results. This study was designed to analyze the need for continued mixing of a Mycoplasma gallisepticum vaccine solution in order to maintain a ...

  17. Unravelling the Transcriptome Profile of the Swine Respiratory Tract Mycoplasmas

    PubMed Central

    Siqueira, Franciele Maboni; Gerber, Alexandra Lehmkuhl; Guedes, Rafael Lucas Muniz; Almeida, Luiz Gonzaga; Schrank, Irene Silveira; Vasconcelos, Ana Tereza Ribeiro; Zaha, Arnaldo

    2014-01-01

    The swine respiratory ciliary epithelium is mainly colonized by Mycoplasma hyopneumoniae, Mycoplasma flocculare and Mycoplasma hyorhinis. While colonization by M. flocculare is virtually asymptomatic, M. hyopneumoniae and M. hyorhinis infections may cause respiratory disease. Information regarding transcript structure and gene abundance provides valuable insight into gene function and regulation, which has not yet been analyzed on a genome-wide scale in these Mycoplasma species. In this study, we report the construction of transcriptome maps for M. hyopneumoniae, M. flocculare and M. hyorhinis, which represent data for conducting comparative studies on the transcriptional repertory. For each species, three cDNA libraries were generated, yielding averages of 415,265, 695,313 and 93,578 reads for M. hyopneumoniae, M. flocculare and M. hyorhinis, respectively, with an average read length of 274 bp. The reads mapping showed that 92%, 98% and 96% of the predicted genes were transcribed in the M. hyopneumoniae, M. flocculare and M. hyorhinis genomes, respectively. Moreover, we showed that the majority of the genes are co-expressed, confirming the previously predicted transcription units. Finally, our data defined the RNA populations in detail, with the map transcript boundaries and transcription unit structures on a genome-wide scale. PMID:25333523

  18. Electron microscopy of Mycoplasma pneumoniae microcolonies grown on solid surfaces.

    PubMed Central

    Kim, C K; Pfister, R M; Somerson, N L

    1977-01-01

    Mycoplasma pneumoniae sprain CL-8 was studied by using various surfaces for adherence and growth. Cells grown on Epon 812, Formvar, carbon, and glass were of similar morphology. Thin Epon pieces were good material for culturing the organisms and examining thin-sectioned microcolonies by transmission electron microscopy. Images PMID:931378

  19. 9 CFR 113.28 - Detection of mycoplasma contamination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Detection of mycoplasma contamination. 113.28 Section 113.28 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... at 100x. (e) Interpretation of test results. (1) If growth appears on at least one of the plates...

  20. 9 CFR 113.28 - Detection of mycoplasma contamination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Detection of mycoplasma contamination. 113.28 Section 113.28 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Standard Procedures §...

  1. Mycoplasma bovis: An emerging pathogen of ranched bison

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycoplasma bovis (M. bovis) is an emerging, primary pathogen of ranched bison (Bison bison) in North America. It causes severe disease among animals in feedlots as well as breeding-age cows and bulls on pasture. Mortality in adult bison is as high as 25 percent, resulting in significant economic l...

  2. Genome Sequence of a Mycoplasma meleagridis Field Strain

    PubMed Central

    Bertolotti, Luigi; Catania, Salvatore; Pourquier, Philippe; Rosati, Sergio

    2016-01-01

    Mycoplasma meleagridis is a major cause of disease and economic loss in turkeys. Here, we report the genome sequence of an M. meleagridis field strain, which enlarges the knowledge about this bacterium and helps the identification of possible coding sequences for drug resistance genes and specific antigens. PMID:26941131

  3. Increased incidence of Mycoplasma pneumoniae infection in Norway 2011.

    PubMed

    Blystad, H; Ånestad, G; Vestrheim, D F; Madsen, S; Rønning, K

    2012-01-01

    Epidemics of Mycoplasma pneumoniae have recently been reported from England and Wales and from Denmark. A similar increase in M. pneumoniae infections was noted in Norway late autumn 2011.The epidemic has resulted in shortage of erythromycin and the use of alternative antibiotics has been recommended. PMID:22321136

  4. Isolation of Mycoplasma hyosynoviae from pneumonic lung of swine.

    PubMed

    Dahlia, H; Tan, L J; Zarrahimah, Z; Maria, J

    2009-12-01

    The isolation of Mycoplasma hyosynoviae from a piglet with severe pneumonia is described. This is the first report of M. hyosynoviae isolation in the country. The lung sample where the isolation was made was severely consolidated, suppurative and pleurisy. The pathogenicity of the M. hyosynoviae isolated has yet to be determined. PMID:20237449

  5. 9 CFR 113.28 - Detection of mycoplasma contamination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of mycoplasma contamination. 113.28 Section 113.28 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Standard Procedures §...

  6. Detecting mycoplasma contamination in cell cultures by polymerase chain reaction.

    PubMed

    Uphoff, Cord C; Drexler, Hans G

    2011-01-01

    The detection of mycoplasmas in human and animal cell cultures is mandatory for every cell culture laboratory, because these bacteria are common contaminants, persist unrecognized in cell cultures for many years, and affect research results as well as the purity of cell culture products. The reliability of the mycoplasma detection depends on the sensitivity and specificity of the method and should also be convenient to be included in the basic routine of cell culture quality assessment. Polymerase chain reaction (PCR) detection is one of the acknowledged methodologies to detect mycoplasmas in cell cultures and cell culture products. Although the PCR offers a fast and simple technique to detect mycoplasmas, the method is also susceptible to errors and can produce false positive as well as false-negative results. Thus, the establishment and the routine application of the PCR assay require optimization and the inclusion of the appropriate control reactions. The presented protocol describes sample preparation, DNA extraction, PCR run, the analysis of the PCR products, and speciation of the contaminant. It also provides detailed information on how to avoid artifacts produced by the method. Established properly, PCR is a reliable, fast, and sensitive method and should be applied regularly to monitor the contamination status of cell cultures. PMID:21516400

  7. 21 CFR 866.3375 - Mycoplasma spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Mycoplasma spp. serological reagents. 866.3375 Section 866.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3375...

  8. 21 CFR 866.3375 - Mycoplasma spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Mycoplasma spp. serological reagents. 866.3375 Section 866.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3375...

  9. 21 CFR 866.3375 - Mycoplasma spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Mycoplasma spp. serological reagents. 866.3375 Section 866.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3375...

  10. 21 CFR 866.3375 - Mycoplasma spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mycoplasma spp. serological reagents. 866.3375 Section 866.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3375...

  11. 21 CFR 866.3375 - Mycoplasma spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Mycoplasma spp. serological reagents. 866.3375 Section 866.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3375...

  12. Protective Immunity against Infection with Mycoplasma haemofelis

    PubMed Central

    Hicks, Chelsea A. E.; Willi, Barbara; Riond, Barbara; Novacco, Marilisa; Meli, Marina L.; Stokes, Christopher R.; Helps, Christopher R.; Hofmann-Lehmann, Regina

    2014-01-01

    Hemoplasmas are potentially zoonotic mycoplasmal pathogens, which are not consistently cleared by antibiotic therapy. Mycoplasma haemofelis is the most pathogenic feline hemoplasma species. The aim of this study was to determine how cats previously infected with M. haemofelis that had recovered reacted when rechallenged with M. haemofelis and to characterize the immune response following de novo M. haemofelis infection and rechallenge. Five specific-pathogen-free (SPF)-derived naive cats (group A) and five cats that had recovered from M. haemofelis infection (group B) were inoculated subcutaneously with M. haemofelis. Blood M. haemofelis loads were measured by quantitative PCR (qPCR), antibody response to heat shock protein 70 (DnaK) by enzyme-linked immunosorbent assay (ELISA), blood lymphocyte cell subtypes by flow cytometry, and cytokine mRNA levels by quantitative reverse transcriptase PCR. Group A cats all became infected with high bacterial loads and seroconverted, while group B cats were protected from reinfection, thus providing the unique opportunity to study the immunological parameters associated with this protective immune response against M. haemofelis. First, a strong humoral response to DnaK was only observed in group A, demonstrating that an antibody response to DnaK is not important for protective immunity. Second, proinflammatory cytokine interleukin-6 (IL-6) mRNA levels appeared to increase rapidly postinoculation in group B, indicating a possible role in protective immunity. Third, an increase in IL-12p35 and -p40 mRNA and decrease in the Th2/Th1 ratio observed in group A suggest that a Th1-type response is important in primary infection. This is the first study to demonstrate protective immunity against M. haemofelis reinfection, and it provides important information for potential future hemoplasma vaccine design. PMID:25410206

  13. Protective immunity against infection with Mycoplasma haemofelis.

    PubMed

    Hicks, Chelsea A E; Willi, Barbara; Riond, Barbara; Novacco, Marilisa; Meli, Marina L; Stokes, Christopher R; Helps, Christopher R; Hofmann-Lehmann, Regina; Tasker, Séverine

    2015-01-01

    Hemoplasmas are potentially zoonotic mycoplasmal pathogens, which are not consistently cleared by antibiotic therapy. Mycoplasma haemofelis is the most pathogenic feline hemoplasma species. The aim of this study was to determine how cats previously infected with M. haemofelis that had recovered reacted when rechallenged with M. haemofelis and to characterize the immune response following de novo M. haemofelis infection and rechallenge. Five specific-pathogen-free (SPF)-derived naive cats (group A) and five cats that had recovered from M. haemofelis infection (group B) were inoculated subcutaneously with M. haemofelis. Blood M. haemofelis loads were measured by quantitative PCR (qPCR), antibody response to heat shock protein 70 (DnaK) by enzyme-linked immunosorbent assay (ELISA), blood lymphocyte cell subtypes by flow cytometry, and cytokine mRNA levels by quantitative reverse transcriptase PCR. Group A cats all became infected with high bacterial loads and seroconverted, while group B cats were protected from reinfection, thus providing the unique opportunity to study the immunological parameters associated with this protective immune response against M. haemofelis. First, a strong humoral response to DnaK was only observed in group A, demonstrating that an antibody response to DnaK is not important for protective immunity. Second, proinflammatory cytokine interleukin-6 (IL-6) mRNA levels appeared to increase rapidly postinoculation in group B, indicating a possible role in protective immunity. Third, an increase in IL-12p35 and -p40 mRNA and decrease in the Th2/Th1 ratio observed in group A suggest that a Th1-type response is important in primary infection. This is the first study to demonstrate protective immunity against M. haemofelis reinfection, and it provides important information for potential future hemoplasma vaccine design. PMID:25410206

  14. Mycoplasma-induced minimally conscious state.

    PubMed

    Horvath, Thomas; Fischer, Urs; Müller, Lionel; Ott, Sebastian; Bassetti, Claudio L; Wiest, Roland; Sendi, Parham; Schefold, Joerg C

    2016-01-01

    Mycoplasma pneumoniae (M. pneumoniae) frequently causes community-acquired respiratory tract infection and often presents as atypical pneumonia. Following airborne infection and a long incubation period, affected patients mostly suffer from mild or even asymptomatic and self-limiting disease. In particular in school-aged children, M. pneumoniae is associated with a wide range of extrapulmonary manifestations including central nervous system (CNS) disease. In contrast to children, severe CNS manifestations are rarely observed in adults. We report a case of a 37 year-old previously healthy immunocompetent adult with fulminant M. pneumoniae-induced progressive encephalomyelitis who was initially able to walk to the emergency department. A few hours later, she required controlled mechanical ventilation for ascending transverse spinal cord syndrome, including complete lower extremity paraplegia. Severe M. pneumoniae-induced encephalomyelitis was postulated, and antimicrobial, anti-inflammatory and immunosuppressive therapy was applied on the intensive care unit. Despite early and targeted therapy using four different immunosuppressive strategies, clinical success was limited. In our patient, locked-in syndrome developed followed by persistent minimally conscious state. The neurological status was unchanged until day 230 of follow-up. Our case underlines that severe M. pneumoniae- related encephalomyelitis must not only be considered in children, but also in adults. Moreover, it can be fulminant and fatal in adults. Our case enhances the debate for an optimal antimicrobial agent with activity beyond the blood-brain barrier. Furthermore, it may underline the difficulty in clinical decision making regarding early antimicrobial treatment in M. pneumoniae disease, which is commonly self-limited. PMID:27026840

  15. Mycoplasmas isolated from the respiratory tract of horses.

    PubMed Central

    Allam, N. M.; Lemcke, R. M.

    1975-01-01

    Ten mycoplasmas were isolated from 130 nasopharyngeal swabs from thoroughbred horses with acute respiratory disease and three from 198 apparently normal horses. Two mycoplasmas were isolated from 21 tracheal swabs taken at necropsy. These mycoplasmas, together with six isolated from the equine respiratory tract by other workers, were subjected to biochemical and serological tests. Other properties examined in certain representative strains were appearance under the electron microscope, ability to adsorb or agglutinate the erythrocytes of various animal species and the electrophoretic pattern of the cell proteins. On the basis of these test, mycoplasmas from the equine respiratory tract were divided into seven species. Three species belonged to the genus Acholeplasma, members of which do not require sterol for growth, and were identified as A. laidlawii, A. oculi (formerly A. oculusi) originally isolated from the eyes of goats, and a recently named species A. equifoetale, previously isolated from aborted equine fetuses. Of the four sterol-dependent Mycoplasma species, one was indentified as M. pulmonis, a common rodent pathogen. Another cross-reacted serologically with M. felis and should probably be classified as that species. The other two species probably represent new species peculiar to the horse. One of these, represented by the strains N3 and N11, ferments glucose and is serologically distinct from 19 recognized species of glucose-utilizing mycoplasmas and from two species which do not metabolize either glucose or arginine. The other species, represented by four strains, hydrolyses arginine and, because it is serologically distinct from all the named arginine-hydrolysing Mycoplasma species, the name M. equirhinis sp.nov. is proposed for it. Of the seven species, only M. pulmonis and the glucose-utilizing species represented by N3 and N11 were found exclusively in horses with acute respiratory disease. A. oculi was isolated from an apparently normal horse. The

  16. [Structure and solidity of new bone in a cortical gliding hole by implanted leg screw (author's transl)].

    PubMed

    Hutzschenreuter, P; Claes, L

    1976-07-23

    Leg screws were implanted in 30 tibia diaphysis. 112 days later in the gliding hole there was new lamellar bone round of the screw head, neck of screw and into the both first screw threads. After screw explantation we measured in 8 cases the solidity of the new bone. Under conditions of tension measurement, we use 341 N per millimeter cortical thread surfaces to put out all new bone from the gliding hole. The results of these tension measurements were cylindric fragments. The remodelling into the gliding hole seems to be the results of static stress and dynamic compensation for reaching a defect in living cortical bone. PMID:962685

  17. What are mycoplasmas: the relationship of tempo and mode in bacterial evolution

    NASA Technical Reports Server (NTRS)

    Woese, C. R.; Stackebrandt, E.; Ludwig, W.

    1984-01-01

    In phenotype the mycoplasmas are very different from ordinary bacteria. However, genotypically (i.e., phylogenetically) they are not. On the basis of ribosomal RNA homologies the mycoplasmas belong with the clostridia, and indeed have specific clostridial relatives. Mycoplasmas are, however, unlike almost all other bacteria in the evolutionary characteristics of their ribosomal RNAs. These RNAs contain relatively few of the highly conserved oligonucleotide sequences characteristic of normal eubacterial ribosomal RNAs. This is interpreted to be a reflection of an elevated mutation rate in mycoplasma lines of descent. A general consequence of this would be that the variation associated with a mycoplasma population is augmented both in number and kind, which in turn would lead to an unusual evolutionary course, one unique in all respects. Mycoplasmas, then, are actually tachytelic bacteria. The unusual evolutionary characteristics of their ribosomal RNAs are the imprints of their rapid evolution.

  18. What are mycoplasmas - The relationship of tempo and mode in bacterial evolution

    NASA Technical Reports Server (NTRS)

    Woese, C. R.; Stackebrand, E.; Ludwig, W.

    1985-01-01

    In phenotype the mycoplasmas are very different from ordinary bacteria. However, genotypically (i.e., phylogenetically) they are not. On the basis of ribosomal RNA homologies the mycoplasmas belong with the clostridia, and indeed have specific clostridial relatives. Mycoplasmas are, however, unlike almost all other bacteria in the evolutionary characteristics of their ribosomal RNAs. These RNAs contain relatively few of the highly conserved oligonucleotide sequences characteristic of normal eubacterial ribosomal RNAs. This is interpreted to be a reflection of an elevated mutation rate in mycoplasma lines of descent. A general consequence of this would be that the variation associated with a mycoplasma population is augmented both in number and kind, which in turn would lead to an unusual evolutionary course, one unique in all respects. Mycoplasmas, then, are actually tachytelic bacteria. The unusual evolutionary characteristics of their ribosomal RNAs are the imprints of their rapid evolution.

  19. Mycoplasma pulmonis Vsa proteins and polysaccharide modulate adherence to pulmonary epithelial cells.

    PubMed

    Bolland, Jeffrey R; Dybvig, Kevin

    2012-06-01

    The Mycoplasma pulmonis Vsa proteins are a family of size- and phase-variable lipoproteins that shield the mycoplasmas from complement and modulate attachment to abiotic surfaces. Mycoplasmas producing a long Vsa protein hemadsorb poorly and yet are proficient at colonizing rats and mice. The effect of the length of the Vsa protein on the attachment of mycoplasmas to epithelial cells has not been previously explored. We find that independent of Vsa isotype, mycoplasmas producing a long Vsa protein with many tandem repeats adhere poorly to murine MLE-12 cells compared with mycoplasmas producing a short Vsa. We also find that mutants lacking the EPS-I polysaccharide of M. pulmonis exhibited decreased adherence to MLE-12 cells, even though it has been shown previously that such mutants have an enhanced ability to form a biofilm. PMID:22428866

  20. Enzootic Pneumonia in Pigs: Propagation of a Causative Mycoplasma in Cell Cultures and in Artificial Medium

    PubMed Central

    L'Ecuyer, C.

    1969-01-01

    Three strains of a new species of mycoplasma were recovered from pneumonic pig lungs, known free of Mycoplasma hyorhinis, by prolonged incubation in pig testicle cell cultures. The three strains produced a characteristic cytopathic effect in the cell cultures. A highly enriched meat-infusion-broth medium was evolved and permitted regular propagation of these organisms. Pneumonia could consistently be produced by intratracheal inoculation of pigs with the mycoplasma propagated in the enriched broth medium or in cell cultures. The mycoplasma were recovered from the lungs of experimentally infected pigs by inoculation into the broth medium. Comparative studies of the pneumonia producing mycoplasma and of M. hyorhinis were carried out in cell cultures, broth media, and in pigs infected experimentally by different routes. The morphological characteristics of the mycoplasma, grown in the different media, are described and illustrated. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 4.Fig. 5.Fig. 6.Fig. 7. PMID:4237289

  1. Aerodynamic force generation, performance and control of body orientation during gliding in sugar gliders (Petaurus breviceps).

    PubMed

    Bishop, Kristin L

    2007-08-01

    Gliding has often been discussed in the literature as a possible precursor to powered flight in vertebrates, but few studies exist on the mechanics of gliding in living animals. In this study I analyzed the 3D kinematics of sugar gliders (Petaurus breviceps) during short glides in an enclosed space. Short segments of the glide were captured on video, and the positions of marked anatomical landmarks were used to compute linear distances and angles, as well as whole body velocities and accelerations. From the whole body accelerations I estimated the aerodynamic forces generated by the animals. I computed the correlations between movements of the limbs and body rotations to examine the control of orientation during flight. Finally, I compared these results to those of my earlier study on the similarly sized and distantly related southern flying squirrel (Glaucomys volans). The sugar gliders in this study accelerated downward slightly (1.0+/-0.5 m s(-2)), and also accelerated forward (2.1+/-0.6 m s(-2)) in all but one trial, indicating that the body weight was not fully supported by aerodynamic forces and that some of the lift produced forward acceleration rather than just balancing body weight. The gliders used high angles of attack (44.15+/-3.12 degrees ), far higher than the angles at which airplane wings would stall, yet generated higher lift coefficients (1.48+/-0.18) than would be expected for a stalled wing. Movements of the limbs were strongly correlated with body rotations, suggesting that sugar gliders make extensive use of limb movements to control their orientation during gliding flight. In addition, among individuals, different limb movements were associated with a given body rotation, suggesting that individual variation exists in the control of body rotations. Under similar conditions, flying squirrels generated higher lift coefficients and lower drag coefficients than sugar gliders, yet had only marginally shallower glides. Flying squirrels have a

  2. Prevalence of Mycoplasma gallisepticum and Mycoplasma synoviae in commercial poultry, racing pigeons and wild birds in Belgium.

    PubMed

    Michiels, Tinne; Welby, Sarah; Vanrobaeys, Mia; Quinet, Christian; Rouffaer, Lieze; Lens, Luc; Martel, An; Butaye, Patrick

    2016-01-01

    Mycoplasma gallisepticum is the most important pathogenic avian Mycoplasma species and causes chronic respiratory disease in poultry. In addition, the prevalence of Mycoplasma synoviae is of increasing concern in several EU member states. We investigated the prevalence of M. gallisepticum in commercial poultry (5220 layers, 1224 broilers and 1020 meat turkeys), 56 racing pigeons and 890 wild birds (Order Anseriformes, Galliformes, Pelecaniformes, Accipitriformes, Gruiformes, Charadriiformes, Columbiformes, Strigiformes, Falconiformes and Passeriformes). Broilers and wild birds were also evaluated for Mycoplasma synoviae. Dependent on the bird lifespan and the nature of the sample, different diagnostic tests were used including the rapid plate agglutination test, enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction and real-time polymerase chain reaction. A low prevalence of M. gallisepticum was found in both layers (0.9%; 95% CI: 0.7-1.2%) and broilers (2.7%; 95% CI: 1.9-3.8%) possibly due to reduced vertical transmission by breeder farms, which are under official surveillance. None of the samples from turkeys or racing pigeons tested positive. In wild birds, we found five birds were positive (1.7%; 95% CI: 0.7-3.9%): one wood pigeon, two grey herons, one mallard and one Eurasian magpie. For M. synoviae a high prevalence was found in broilers (12.9%: 95% CI: 11.1-14.9%). Four samples collected by hunters gave a positive result for M. synoviae (4%: 95% CI: 1.6-9.8%): one carrion crow and three wood pigeons. In addition, 12 house sparrows were found to be positive (3%; 95% CI: 1.7-5.2%). Wild birds probably play a limited role as a reservoir but we cannot exclude a possible impact on transmission of Mycoplasmas. PMID:26814376

  3. 3D microfluidic chips with integrated functional microelements fabricated by a femtosecond laser for studying the gliding mechanism of cyanobacteria.

    PubMed

    Hanada, Yasutaka; Sugioka, Koji; Shihira-Ishikawa, Ikuko; Kawano, Hiroyuki; Miyawaki, Atsushi; Midorikawa, Katsumi

    2011-06-21

    Phormidium, a genus of filamentous cyanobacteria, forms endosymbiotic associations with seedling roots that accelerate the growth of the vegetable seedlings. Understanding the gliding mechanism of Phormidium will facilitate improved formation of this association and increased vegetable production. To observe the gliding movements, we fabricated various microfluidic chips termed nanoaquariums using a femtosecond (fs) laser. Direct fs laser writing, followed by annealing and successive wet etching in dilute hydrofluoric acid solution, can easily produce three-dimensional (3D) microfluidics with different structures embedded in a photostructurable glass. Using the fs laser, optical waveguides and filters were integrated with the microfluidic structures in the microchips, allowing the gliding mechanism to be more easily clarified. Using this apparatus, we found that CO(2) secreted from the seedling root attracts Phormidium in the presence of light, and determined the light intensity and specific wavelength necessary for gliding. PMID:21562650

  4. Construction of the mycoplasma evolutionary tree from 5S rRNA sequence data.

    PubMed Central

    Rogers, M J; Simmons, J; Walker, R T; Weisburg, W G; Woese, C R; Tanner, R S; Robinson, I M; Stahl, D A; Olsen, G; Leach, R H

    1985-01-01

    The 5S rRNA sequences of eubacteria and mycoplasmas have been analyzed and a phylogenetic tree constructed. We determined the sequences of 5S rRNA from Clostridium innocuum, Acholeplasma laidlawii, Acholeplasma modicum, Anaeroplasma bactoclasticum, Anaeroplasma abactoclasticum, Ureaplasma urealyticum, Mycoplasma mycoides mycoides, Mycoplasma pneumoniae, and Mycoplasma gallisepticum. Analysis of these and published sequences shows that mycoplasmas form a coherent phylogenetic group that, with C. innocuum, arose as a branch of the low G+C Gram-positive tree, near the lactobacilli and streptococci. The initial event in mycoplasma phylogeny was formation of the Acholeplasma branch; hence, loss of cell wall probably occurred at the time of genome reduction to approximately to 1000 MDa. A subsequent branch produced the Spiroplasma. This branch appears to have been the origin of sterol-requiring mycoplasmas. During development of the Spiroplasma branch there were several independent genome reductions, each to approximately 500 MDa, resulting in Mycoplasma and Ureaplasma species. Mycoplasmas, particularly species with the smallest genomes, have high mutation rates, suggesting that they are in a state of rapid evolution. PMID:2579388

  5. Studies on the Nature of Receptors Involved in Attachment of Tissue Culture Cells to Mycoplasmas

    PubMed Central

    Manchee, R. J.; Taylor-Robinson, D.

    1969-01-01

    Several mycoplasmas, from avian and mammalian sources, growing in the form of colonies on agar and sheets attached to plastic dishes, were tested for their ability to adsorb tissue culture cells in suspension. HeLa cells adsorbed to the majority of mycoplasmas tested; adsorption occurred to the sheets and not to the colonies of some mycoplasmas. Other tissue cells, in primary culture and of diploid origin, adsorbed also. The mechanism of adsorption of HeLa cells to 4 mycoplasmas was examined by treating the cells and mycoplasmas in various ways and then testing for adsorption. N-acetyl neuraminic acid residues on the tissue cells were responsible for adsorption to M. gallisepticum and M. pneumoniae. The receptors for M. hominis and M. salivarium were probably not of this kind since treatment of the cells with purified neuraminidase did not influence adsorption. However, the cell receptors for these mycoplasmas were associated with protein because they were inactivated by proteolytic enzymes and by formalin. The cell receptors for M. hominis were more heat stable than those for the other mycoplasmas. From the aspect of the mycoplasma membrane, in no instance did neuraminidase treatment affect adsorption. On the other hand, various experiments suggested that protein components of the mycoplasma membrane were involved. The significance of these findings is discussed. PMID:5773147

  6. Interlayer-glide-driven isosymmetric phase transition in compressed In2Se3

    NASA Astrophysics Data System (ADS)

    Ke, Feng; Liu, Cailong; Gao, Yang; Zhang, Junkai; Tan, Dayong; Han, Yonghao; Ma, Yanzhang; Shu, Jinfu; Yang, Wenge; Chen, Bin; Mao, Ho-Kwang; Chen, Xiao-Jia; Gao, Chunxiao

    2014-05-01

    We report an anomalous phase transition in compressed In2Se3. The high-pressure studies indicate that In2Se3 transforms to a new isosymmetric R-3m structure at 0.8 GPa whilst the volume collapses by ˜7%. This phase transition involves a pressure-induced interlayer shear glide with respect to one another. Consequently, the outer Se atoms of one sheet locate into the interstitial sites of three Se atoms in the neighboring sheets that are weakly connected by van der Waals interaction. Interestingly, this interlayer shear glide changes the stacking sequence significantly but leaves crystal symmetry unaffected. This study provides an insight to the mechanisms of the intriguing isosymmetric phase transition.

  7. An innovative way to reinsert dislodged Arndt blocker using urological glide wire

    PubMed Central

    Pillai, Rahul; Ancheri, Sneha Ann; Dharmalingam, Sathish Kumar; Sahajanandan, Raj

    2016-01-01

    The Arndt blocker is positioned in the desired bronchus using a wire loop which couples the blocker with a fiberoptic bronchoscope (FOB). The wire loop once removed cannot be reinserted in 5F and 7F blockers making repositioning of the blocker difficult. A 34-year-old female was to undergo left thoracotomy followed by laparoscopic cholecystectomy. The left lung was isolated with a 7F Arndt bronchial blocker. During one-lung ventilation, the wire loop was removed for oxygen insufflation. There was loss of lung isolation during the procedure and dislodgement of the blocker was confirmed by FOB. The initial attempts to reintroduce the blocker into the left main bronchus failed. An alternative technique using a glide wire was attempted which resulted in successful reintroduction of the Arndt blocker. The 0.032 inch zebra glide wire may be effectively used to reposition a dislodged Arndt blocker if the wire loop has been removed. PMID:27052085

  8. The History of Mycoplasma pneumoniae Pneumonia

    PubMed Central

    Saraya, Takeshi

    2016-01-01

    Pinehurst transmission experiments resulted in a lapse of 20 years before acceptance of the Eaton agent as Mycoplasma pneumoniae. This review describes the history of M. pneumoniae pneumonia with a special focus on the recognition between the 1930 and 1960s of the Eaton agent as the infectious cause. PMID:27047477

  9. The History of Mycoplasma pneumoniae Pneumonia.

    PubMed

    Saraya, Takeshi

    2016-01-01

    transmission experiments resulted in a lapse of 20 years before acceptance of the Eaton agent as Mycoplasma pneumoniae. This review describes the history of M. pneumoniae pneumonia with a special focus on the recognition between the 1930 and 1960s of the Eaton agent as the infectious cause. PMID:27047477

  10. Feather roughness reduces flow separation during low Reynolds number glides of swifts.

    PubMed

    van Bokhorst, Evelien; de Kat, Roeland; Elsinga, Gerrit E; Lentink, David

    2015-10-01

    Swifts are aerodynamically sophisticated birds with a small arm and large hand wing that provides them with exquisite control over their glide performance. However, their hand wings have a seemingly unsophisticated surface roughness that is poised to disturb flow. This roughness of about 2% chord length is formed by the valleys and ridges of overlapping primary feathers with thick protruding rachides, which make the wing stiffer. An earlier flow study of laminar-turbulent boundary layer transition over prepared swift wings suggested that swifts can attain laminar flow at a low angle of attack. In contrast, aerodynamic design theory suggests that airfoils must be extremely smooth to attain such laminar flow. In hummingbirds, which have similarly rough wings, flow measurements on a 3D printed model suggest that the flow separates at the leading edge and becomes turbulent well above the rachis bumps in a detached shear layer. The aerodynamic function of wing roughness in small birds is, therefore, not fully understood. Here, we performed particle image velocimetry and force measurements to compare smooth versus rough 3D-printed models of the swift hand wing. The high-resolution boundary layer measurements show that the flow over rough wings is indeed laminar at a low angle of attack and a low Reynolds number, but becomes turbulent at higher values. In contrast, the boundary layer over the smooth wing forms open laminar separation bubbles that extend beyond the trailing edge. The boundary layer dynamics of the smooth surface varies non-linearly as a function of angle of attack and Reynolds number, whereas the rough surface boasts more consistent turbulent boundary layer dynamics. Comparison of the corresponding drag values, lift values and glide ratios suggests, however, that glide performance is equivalent. The increased structural performance, boundary layer robustness and equivalent aerodynamic performance of rough wings might have provided small (proto) birds with

  11. Quadrupedal locomotor performance in two species of arboreal squirrels: predicting energy savings of gliding.

    PubMed

    Flaherty, Elizabeth A; Ben-David, Merav; Smith, Winston P

    2010-10-01

    Gliding allows mammals to exploit canopy habitats of old-growth forests possibly as a means to save energy. To assess costs of quadrupedal locomotion for a gliding arboreal mammal, we used open-flow respirometry and a variable-speed treadmill to measure oxygen consumption and to calculate cost of transport, excess exercise oxygen consumption, and excess post-exercise oxygen consumption for nine northern flying squirrels (Glaucomys sabrinus) and four fox squirrels (Sciurus niger). Our results indicate that oxygen consumption during exercise by flying squirrels was 1.26-1.65 times higher than predicted based on body mass, and exponentially increased with velocity (from 0.84 ± 0.03 ml O(2) kg(-1) s(-1) at 0.40 m s(-1) to 1.55 ± 0.03 ml O(2) kg(-1) s(-1) at 0.67 m s(-1)). Also, cost of transport in flying squirrels increased with velocity, although excess exercise oxygen consumption and excess post-exercise oxygen consumption did not. In contrast, oxygen consumption during exercise for fox squirrels was similar to predicted, varying from 0.51 (±0.02) ml O(2) kg(-1) s(-1) at 0.63 m s(-1) to 0.54 (±0.03) ml O(2) kg(-1) s(-1) at 1.25 m s(-1). In addition, the cost of transport for fox squirrels decreased with velocity, while excess exercise oxygen consumption and excess post-exercise oxygen consumption did not. Collectively, these observations suggest that unlike fox squirrels, flying squirrels are poorly adapted to prolonged bouts of quadrupedal locomotion. The evolution of skeletal adaptations to climbing, leaping, and landing and the development of a gliding membrane likely has increased the cost of quadrupedal locomotion by >50% while resulting in energy savings during gliding and reduction in travel time between foraging patches. PMID:20361193

  12. On the irradiation creep by climb-enabled glide of dislocations

    NASA Astrophysics Data System (ADS)

    Barashev, A. V.; Golubov, S. I.; Stoller, R. E.

    2016-08-01

    In the climb-enabled glide model of irradiation creep, the plastic deformation is defined by the elastic deflections of pinned dislocations, which is an inconsistency. We argue that this relation is incorrect; instead, as in other pinning-unpinning-type models, the dislocations move from one set of obstacles to another, so that the inter-obstacle spacing determines creep rate, whereas the dependence on the applied stress is only implicit in the unpinning time.

  13. Sandbox experiments on gravitational spreading and gliding in the presence of fluid overpressures

    NASA Astrophysics Data System (ADS)

    Mourgues, R.; Cobbold, P. R.

    2006-05-01

    Whereas in previous analogue experiments on gravitational spreading and gliding, detachment occurred on a ductile layer, we have used a relatively new technique of injecting compressed air into sand packs so as to simulate the effects of fluid overpressures in sedimentary strata and to trigger slope instabilities. In our experiments, the governing equations yield scales for dimensions, stresses and fluid pressure. However, the more transitory phenomena of production and decrease of overpressure cannot be suitably scaled. By using layers of differing permeability, we are able to produce sharp detachments in models made of sand alone. The experiments involve gravity spreading or gravity gliding. In gravity spreading, propagation of the detachment and of extensional deformation depends on the fluid pressure. For medium values of fluid overpressure, normal faults are closely spaced, numerous and bound rotated blocks. They propagate progressively toward the back of the model. For the highest pressures, the deformation propagates very fast and faults bound non-rotated blocks, which slide on an efficient basal detachment. Fault dips are also controlled by fluid pressure and by frictional resistance at the base. To model gravitational gliding required an apparatus with a more complex system of air injection. We did a series of experiments using injection windows of various lengths and compared the results with predictions from a quasi-3D analytical model of sliding. In contrast with predictions for an infinite slope, sliding depends on (1) the fluid overpressure on the detachment, (2) the fluid overpressure in the body of the sliding sheet, and (3) the shape of the detachment surface. In particular, we show that frictional resistance at the lower edge is a primary control on the dynamics of gliding.

  14. GLIDE: a grid-based light-weight infrastructure for data-intensive environments

    NASA Technical Reports Server (NTRS)

    Mattmann, Chris A.; Malek, Sam; Beckman, Nels; Mikic-Rakic, Marija; Medvidovic, Nenad; Chrichton, Daniel J.

    2005-01-01

    The promise of the grid is that it will enable public access and sharing of immense amounts of computational and data resources among dynamic coalitions of individuals and institutions. However, the current grid solutions make several limiting assumptions that curtail their widespread adoption. To address these limitations, we present GLIDE, a prototype light-weight, data-intensive middleware infrastructure that enables access to the robust data and computational power of the grid on DREAM platforms.

  15. Generation of a monoclonal antibody against Mycoplasma spp. following accidental contamination during production of a monoclonal antibody against Lawsonia intracellularis.

    PubMed

    Hwang, Jeong-Min; Lee, Ji-Hye; Yeh, Jung-Yong

    2012-03-01

    This report describes Mycoplasma contamination of Lawsonia intracellularis cultures that led to the unintended acquisition of a monoclonal antibody against Mycoplasma spp. during the attempted generation of a monoclonal antibody against L. intracellularis. PMID:22247145

  16. Prosodic effects on glide-vowel sequences in three Romance languages

    NASA Astrophysics Data System (ADS)

    Chitoran, Ioana

    2001-05-01

    Glide-vowel sequences occur in many Romance languages. In some they can vary in production, ranging from diphthongal pronunciation [ja,je] to hiatus [ia,ie]. According to native speakers' impressionistic perceptions, Spanish and Romanian both exhibit this variation, but to different degrees. Spanish favors glide-vowel sequences, while Romanian favors hiatus, occasionally resulting in different pronunciations of the same items: Spanish (b[j]ela, ind[j]ana), Romanian (b[i]ela, ind[i]ana). The third language, French, has glide-vowel sequences consistently (b[j]elle). This study tests the effect of position in the word on the acoustic duration of the sequences. Shorter duration indicates diphthong production [jV], while longer duration, hiatus [iV]. Eleven speakers (4 Spanish, 4 Romanian, 3 French), were recorded. Spanish and Romanian showed a word position effect. Word-initial sequences were significantly longer than word-medial ones (p<0.001), consistent with native speakers more frequent description of hiatus word-initially than medially. The effect was not found in French (p>0.05). In the Spanish and Romanian sentences, V in the sequence bears pitch accent, but not in French. It is therefore possible that duration is sensitive not to the presence/absence of the word boundary, but to its position relative to pitch accent. The results suggest that the word position effect is crucially enhanced by pitch accent on V.

  17. A theoretical analysis of pitch stability during gliding in flying snakes.

    PubMed

    Jafari, Farid; Ross, Shane D; Vlachos, Pavlos P; Socha, John J

    2014-06-01

    Flying snakes use their entire body as a continuously morphing 'wing' to produce lift and shallow their glide trajectory. Their dominant behavior during gliding is aerial undulation, in which lateral waves are sent posteriorly down the body. This highly dynamic behavior, which is unique among animal gliders, should have substantial effects on the flight dynamics and stability of the snakes, resulting from the continuous redistribution of mass and aerodynamic forces. In this study, we develop two-dimensional theoretical models to assess the stability characteristics of snakes in the pitch direction. Previously measured force coefficients are used to simulate aerodynamic forces acting on the models, and undulation is simulated by varying mass. Model 1 is a simple three-airfoil representation of the snake's body that possesses a passively stable equilibrium solution, whose basin of stability contains initial conditions observed in experimental gliding trajectories. Model 2 is more sophisticated, with more degrees of freedom allowing for postural changes to better represent the snake's real kinematics; in addition, a restoring moment is added to simulate potential active control. The application of static and dynamic stability criteria show that Model 2 is passively unstable, but can be stabilized with a restoring moment. Overall, these models suggest that undulation does not contribute to stability in pitch, and that flying snakes require a closed-loop control system formed around a passively stable dynamical framework. PMID:24852642

  18. Wake analysis of aerodynamic components for the glide envelope of a jackdaw (Corvus monedula).

    PubMed

    KleinHeerenbrink, Marco; Warfvinge, Kajsa; Hedenström, Anders

    2016-05-15

    Gliding flight is a relatively inexpensive mode of flight used by many larger bird species, where potential energy is used to cover the cost of aerodynamic drag. Birds have great flexibility in their flight configuration, allowing them to control their flight speed and glide angle. However, relatively little is known about how this flexibility affects aerodynamic drag. We measured the wake of a jackdaw (Corvus monedula) gliding in a wind tunnel, and computed the components of aerodynamic drag from the wake. We found that induced drag was mainly affected by wingspan, but also that the use of the tail has a negative influence on span efficiency. Contrary to previous work, we found no support for the separated primaries being used in controlling the induced drag. Profile drag was of similar magnitude to that reported in other studies, and our results suggest that profile drag is affected by variation in wing shape. For a folded tail, the body drag coefficient had a value of 0.2, rising to above 0.4 with the tail fully spread, which we conclude is due to tail profile drag. PMID:26994178

  19. Methods to Improve Success With the GlideScope Video Laryngoscope.

    PubMed

    Nemec, Darrell; Austin, Paul N; Silvestro, Loraine S

    2015-12-01

    Occasionally intubation of patients is difficult using a video laryngoscope (GlideScope, Verathon Medical) because of an inability to guide the endotracheal tube to the glottis or pass the tube into the trachea despite an adequate view of the glottis. We examined methods to improve success when this difficulty occurs. A literature search revealed 253 potential sources, with 25 meeting search criteria: 7 randomized controlled trials, 4 descriptive studies, 8 case series, and 6 case reports. Findings from the randomized controlled trials suggested that using a flexible-tipped endotracheal tube with a rigid stylet (GlideRite, Verathon Medical) improved intubation success, whereas other methods did not, such as using a forceps-guided endotracheal tube exchanger. If a malleable stylet was used, a 90 degrees bend above the endotracheal tube cuff was preferable to a 60 degrees bend. Evidence from lower-level sources suggested that several interventions were helpful, including using a controllable stylet, a fiberoptic bronchoscope in conjunction with the GlideScope, or an intubation guide, and twisting the endotracheal tube to facilitate passage into the trachea. Providers must consider the risks and benefits of any technique, particularly if the device manufacturer does not recommend the technique. Further rigorous investigations should be conducted examining methods to increase success. PMID:26742332

  20. Effects of cervical sustained natural apophyseal glide on forward head posture and respiratory function

    PubMed Central

    Kim, Se-Yoon; Kim, Nan-Soo; Kim, Laurentius Jongsoon

    2015-01-01

    [Purpose] To determine the effects of cervical sustained natural apophyseal glide on forward head posture and respiratory function. [Subjects and Methods] Thirty male and female adults in their 20s with forward head posture were included in the study. The subjects were divided randomly into experimental and control groups (n=15 each). Subjects in the experimental group performed cervical sustained natural apophyseal glide three times/week for four weeks while subjects in the control group did not perform the intervention. The craniovertebral angle, forced vital capacity and forced expiratory volume in the first second, as well as the % predicted value of each measurement were assessed to determine the changes in respiration functions before and after the exercise. [Results] The craniovertebral angle four weeks after the experiment was increased in the experimental group, whereas the control group showed no significant difference compared to baseline. The forced vital capacity, forced expiratory volume in the first second, and the % predicted values thereof were significantly increased in the experimental group four weeks after the experiment, but not in the control group. [Conclusion] Cervical sustained natural apophyseal glide was determined to be effective in improving neck posture and respiratory functions for patients with forward head posture. PMID:26180334

  1. Postoperative Sore Throat After Laryngoscopy With Macintosh or Glide Scope Video Laryngoscope Blade in Normal Airway Patients

    PubMed Central

    Najafi, Atabak; Imani, Farsad; Makarem, Jalil; Khajavi, Mohammad Reza; Etezadi, Farhad; Habibi, Shirin; Shariat Moharari, Reza

    2014-01-01

    Background: The Glide Scope videolaryngoscope provides a suitable view for intubation, with less force required. Objectives: The present study was conducted, to compare postoperative sore throat and hoarseness after laryngoscopy and intubation, by Macintosh blade or Glide Scope video laryngoscope in normal airway patients. Patients and Methods: Three hundred patients were randomly allocated into two groups of 150: Macintosh blade laryngoscope or Glide Scope video laryngoscope. The patients were evaluated for 48 hours for sore throat and hoarseness by an interview. Results: The incidence and severity of sore throat in the Glide Scope group, at 6, 24 and 48 hours after the operation, were significantly lower than in the Macintosh laryngoscope group. In addition, the incidence of hoarseness in the Glide Scope group, at 6 and 24 hours after the operation, were significantly lower than in the Macintosh laryngoscope group. The incidence and severity of sore throat in men, at 6 and 24 hours after the operation, were significantly lower than in the women. Conclusions: The incidence and severity of sore throat and hoarseness after tracheal intubation by Glide Scope were lower than in the Macintosh laryngoscope. The incidence and severity of sore throat were increased by intubation and longer operation times. PMID:24660157

  2. Mycoplasmas in Australian fur seals (Arctocephalus pusillus doriferus): identification and association with abortion.

    PubMed

    Lynch, Michael; Taylor, Trevor K; Duignan, Pádraig J; Swingler, Jane; Marenda, Marc; Arnould, John P Y; Kirkwood, Roger

    2011-11-01

    Bacteria from the genus Mycoplasma are common inhabitants of the respiratory, gastrointestinal, and genital tracts of mammals. The understanding of the pathological significance of mycoplasmas in seals is poor, as few studies have utilized the specific culture techniques required to isolate these bacteria. The current study surveyed for the Mycoplasma species present in Australian fur seals (Arctocephalus pusillus doriferus) and investigated the association between infection and pathology. Mycoplasmas were found in the nasal cavities of 55/80 (69%) of apparently healthy individuals. Isolates from 18 individuals were investigated through 16S ribosomal RNA sequencing, and 3 species were identified: M. zalophi, M. phocae, and Mycoplasma sp. (GenBank no. EU714238.1), all of which had previously been isolated from Northern Hemisphere pinnipeds. In addition, mycoplasmas were isolated from the lungs of 4 out of 16 juveniles and 1 out of 5 adults sampled at necropsy. Isolates obtained were M. zalophi, Mycoplasma sp. EU714238.1, and M. phocicerebrale, but infection was not associated with lung pathology in these age classes. Inflammatory disease processes of the heart and/or lungs were present in 12 out of 32 (38%) aborted fetuses on microscopic examination. Predominant findings were interstitial pneumonia, pericarditis, and myocarditis. Mycoplasma phocicerebrale was isolated from the thymus of an aborted fetus, and 3 out of 11 (27%) fetuses with inflammatory heart or lung lesions were PCR-positive for Mycoplasma. In conclusion, several species of Mycoplasma are part of the normal flora of the nasal cavity of Australian fur seals, and some mycoplasmas may be associated with abortion in this species of seal. PMID:22362792

  3. Restless legs syndrome: association with streptococcal or mycoplasma infection.

    PubMed

    Matsuo, Muneaki; Tsuchiya, Katsunori; Hamasaki, Yuhei; Singer, Harvey S

    2004-08-01

    Group A beta-hemolytic streptococcal infections have been reported to cause neuropsychiatric symptoms, such as chorea, tics, and obsessive-compulsive disorder, presumably through autoimmune damage to basal ganglia. Mycoplasma pneumoniae infections have also been reported to cause damage to the basal ganglia. Restless legs syndrome is a movement disorder with focal restlessness, an irresistible desire to move, and exacerbation by long periods of sitting or lying. We present three children with transient restless legs syndrome-like symptoms possibly associated with group A beta-hemolytic streptococcal infection or Mycoplasma pneumoniae infection. One of three patients had persistently elevated enzyme-linked immunosorbent optical density values against human caudate and putamen. PMID:15301831

  4. Mycoplasma testudineum in free-ranging desert tortoises, Gopherus agassizii

    USGS Publications Warehouse

    Jacobson, Elliott R.; Berry, Kristin H.

    2012-01-01

    We performed clinico-pathological evaluations of 11 wild Agassiz's desert tortoises (Gopherus agassizii) from a translocation project in the central Mojave Desert, California, USA. Group 1 consisted of nine tortoises that were selected primarily due to serologic status, indicating exposure to Mycoplasma testudineum (seven) or both M. agassizii and M. testudineum (two), and secondarily due to clinical signs of upper respiratory tract disease (URTD). Group 2 consisted of two tortoises that were antibody-negative for Mycoplasma and had no clinical signs of URTD, but did have other signs of illness. Of the Group 1 tortoises, M. testudineum, but not M. agassizii, was amplified by polymerase chain reaction and DNA fingerprinted from two tortoises. Using light microscopy, mild to severe pathologic changes were observed in one or more histologic sections of either one or both nasal cavities of each tortoise in Group 1. Our findings support a causal relationship between M. testudineum and URTD in desert tortoises.

  5. Mycoplasma testudineum in free-ranging desert tortoises, Gopherus agassizii.

    PubMed

    Jacobson, Elliott R; Berry, Kristin H

    2012-10-01

    We performed clinico-pathological evaluations of 11 wild Agassiz's desert tortoises (Gopherus agassizii) from a translocation project in the central Mojave Desert, California, USA. Group 1 consisted of nine tortoises that were selected primarily due to serologic status, indicating exposure to Mycoplasma testudineum (seven) or both M. agassizii and M. testudineum (two), and secondarily due to clinical signs of upper respiratory tract disease (URTD). Group 2 consisted of two tortoises that were antibody-negative for Mycoplasma and had no clinical signs of URTD, but did have other signs of illness. Of the Group 1 tortoises, M. testudineum, but not M. agassizii, was amplified by polymerase chain reaction and DNA fingerprinted from two tortoises. Using light microscopy, mild to severe pathologic changes were observed in one or more histologic sections of either one or both nasal cavities of each tortoise in Group 1. Our findings support a causal relationship between M. testudineum and URTD in desert tortoises. PMID:23060510

  6. Characterization of Free Exopolysaccharides Secreted by Mycoplasma mycoides Subsp. mycoides

    PubMed Central

    Bertin, Clothilde; Pau-Roblot, Corinne; Courtois, Josiane; Manso-Silván, Lucía; Thiaucourt, François; Tardy, Florence; Le Grand, Dominique; Poumarat, François; Gaurivaud, Patrice

    2013-01-01

    Contagious bovine pleuropneumonia is a severe respiratory disease of cattle that is caused by a bacterium of the Mycoplasma genus, namely Mycoplasma mycoides subsp. mycoides (Mmm). In the absence of classical virulence determinants, the pathogenicity of Mmm is thought to rely on intrinsic metabolic functions and specific components of the outer cell surface. One of these latter, the capsular polysaccharide galactan has been notably demonstrated to play a role in Mmm persistence and dissemination. The free exopolysaccharides (EPS), also produced by Mmm and shown to circulate in the blood stream of infected cattle, have received little attention so far. Indeed, their characterization has been hindered by the presence of polysaccharide contaminants in the complex mycoplasma culture medium. In this study, we developed a method to produce large quantities of EPS by transfer of mycoplasma cells from their complex broth to a chemically defined medium and subsequent purification. NMR analyses revealed that the purified, free EPS had an identical β(1−>6)-galactofuranosyl structure to that of capsular galactan. We then analyzed intraclonal Mmm variants that produce opaque/translucent colonies on agar. First, we demonstrated that colony opacity was related to the production of a capsule, as observed by electron microscopy. We then compared the EPS extracts and showed that the non-capsulated, translucent colony variants produced higher amounts of free EPS than the capsulated, opaque colony variants. This phenotypic variation was associated with an antigenic variation of a specific glucose phosphotransferase permease. Finally, we conducted in silico analyses of candidate polysaccharide biosynthetic pathways in order to decipher the potential link between glucose phosphotransferase permease activity and attachment/release of galactan. The co-existence of variants producing alternative forms of galactan (capsular versus free extracellular galactan) and associated with an

  7. A change in the genetic code in Mycoplasma capricolum

    NASA Technical Reports Server (NTRS)

    Jukes, T. H.

    1985-01-01

    Mycoplasma capricolum was previously found to use UGA instead of UGG as its codon for tryptophan and to contain 75 percent A + T in its DNA. The codon change could have been due to mutational pressure to replace C + G by A + T, resulting in the replacement of UGA stop codons by UAA, change of the anticodon in tryptophan tRNA from CCA to UCA, and replacement of UGG tryptophan codons by UGA. None of these changes should have been deleterious.

  8. Rhamnose Links Moonlighting Proteins to Membrane Phospholipid in Mycoplasmas.

    PubMed

    Daubenspeck, James M; Liu, Runhua; Dybvig, Kevin

    2016-01-01

    Many proteins that have a primary function as a cytoplasmic protein are known to have the ability to moonlight on the surface of nearly all organisms. An example is the glycolytic enzyme enolase, which can be found on the surface of many types of cells from bacteria to human. Surface enolase is not enzymatic because it is monomeric and oligomerization is required for glycolytic activity. It can bind various molecules and activate plasminogen. Enolase lacks a signal peptide and the mechanism by which it attaches to the surface is unknown. We found that treatment of whole cells of the murine pathogen Mycoplasma pulmonis with phospholipase D released enolase and other common moonlighting proteins. Glycostaining suggested that the released proteins were glycosylated. Cytoplasmic and membrane-bound enolase was isolated by immunoprecipitation. No post-translational modification was detected on cytoplasmic enolase, but membrane enolase was associated with lipid, phosphate and rhamnose. Treatment with phospholipase released the lipid and phosphate from enolase but not the rhamnose. The site of rhamnosylation was identified as a glutamine residue near the C-terminus of the protein. Rhamnose has been found in all species of mycoplasma examined but its function was previously unknown. Mycoplasmas are small bacteria with have no peptidoglycan, and rhamnose in these organisms is also not associated with polysaccharide. We suggest that rhamnose has a central role in anchoring proteins to the membrane by linkage to phospholipid, which may be a general mechanism for the membrane association of moonlighting proteins in mycoplasmas and perhaps other bacteria. PMID:27603308

  9. Experimental evidence of indirect transmission of Mycoplasma synoviae.

    PubMed

    Marois, Corinne; Picault, Jean-Paul; Kobisch, Marylène; Kempf, Isabelle

    2005-01-01

    The aim of the study was to analyse experimental transmission of Mycoplasma synoviae, an avian pathogen. Three experiments using specific pathogen-free day-old chicks placed in isolators were conducted. In the first experiment, the birds were introduced in an isolator previously contaminated with a M. synoviae broth culture. After 34 days, these birds were eliminated and, for the second trial, the chicks were introduced in the same isolator without disinfecting. In the third assay, the chicks were placed in an isolator containing a mixture of food, feathers and dust collected less than an hour earlier from a M. synoviae infected laying hen flock. In the second and third experiments in order to exacerbate the M. synoviae infection, the birds were inoculated with infectious bronchitis (IB) virus. The presence of M. synoviae in the environment and in tracheal swabs was monitored by culture, a multiplex PCR (mPCR) detecting M. synoviae and Mycoplasma 16S rDNA and a multiplex RT-PCR (mRT-PCR) detecting the M. synoviae mRNA coding for a membrane protein and Mycoplasma 16S rRNA. In in vitro experimental conditions, M. synoviae mRNA and 16S rRNA were detected up to 20 min and 23 h respectively after mycoplasma death. In the first assay, the first infected bird was detected on the 13th day. In the second trial, culturable M. synoviae or viable M. synoviae were detected in the isolator for 3 or 4 to 5 days respectively after depopulation of the birds of the first assay whereas the first culture positive tracheal swabs were detected on the 33rd day, after IB inoculation. In the third experiment, the first infected birds were detected on the 54th day. Thus, the different assays showed that M. synoviae contaminated material (dust, feathers and food) can infect chicks, sometimes after remarkably long silent periods. PMID:16120251

  10. Mycoplasma synoviae infection on Newcastle disease vaccination of chickens

    PubMed Central

    de Cássia Figueira Silva, Rita; do Nascimento, Elmiro Rosendo; de Almeida Pereira, Virgínia Léo; Barreto, Maria Lúcia; do Nascimento, Maria da Graça Fichel

    2008-01-01

    Newcastle disease is characterized by respiratory manifestations in association with nervous and/or digestive symptoms. Its prevention is done by vaccination with live attenuated (lentogenic strains) and/or killed vaccines. The lentogenic strains can lead to strong post-vaccination reaction, principally due to the presence of other pathogenic agents. Among them, Mycoplasma synoviae is worldwide important, mainly in Brazil. The dissemination of this agent in poultry flocks has been achieved due to difficulties in diagnosis and disease reproduction, virulence variations among different M.synoviae strains, and attribution of typical M.synoviae disease manifestation to other disease agents. This experimental study in SPF chicks (Gallus gallus), previously infected by M.synoviae and thereafter vaccinated against Newcastle disease, was done with the objective of evaluating M.synoviae pathogenicity through assessment of post-vaccinal respiratory reactions and serologic responses to Newcastle disease virus vaccine in the absence of environmental factors. A total of 86 three days old chicks were used, being 57 infected by eye and nostril drop, with chicken activated M. synoviae strain WVU 1853. Seven days later, 21 mycoplasma infected birds plus 29 not mycoplasma infected ones were vaccinated against Newcastle disease. As results, the not infected and vaccinated birds yielded, significantly, higher and longer lasting serologic responses to Newcastle disease vaccine virus than those infected and vaccinated. Similarly, the infected and vaccinated birds yielded lower serologic reactions to M.synoviae than those only mycoplasma infected. No post-vaccinal respiratory reaction was observed in the vaccinated birds. PMID:24031234

  11. Mycoplasma bovis mastitis and arthritis in a dairy heifer.

    PubMed

    2015-12-19

    Mycoplasma bovis causing mastitis and arthritis in a dairy heifer. Nutritional myopathy in a three-month-old suckler calf. Acute fasciolosis in ewes in Ayrshire. Cardiomyopathy of unknown aetiology causing death of a three-year-old Suffolk ram. Spinal aspergillosis in a seven-week-old pheasant poult These are among matters discussed in the disease surveillance report for August from SAC Consulting: Veterinary Services (SAC C VS). PMID:26679914

  12. GPCR Ligand Dendrimer (GLiDe) Conjugates: Adenosine Receptor Interactions of a Series of Multivalent Xanthine Antagonists

    PubMed Central

    Kecskés, Angela; Tosh, Dilip K.; Wei, Qiang; Gao, Zhan-Guo; Jacobson, Kenneth A.

    2011-01-01

    Previously, G protein–coupled receptor (GPCR) agonists were tethered from polyamidoamine (PAMAM) dendrimers to provide high receptor affinity and selectivity. Here we prepared GPCR Ligand Dendrimer (GLiDe) conjugates from a potent adenosine receptor (AR) antagonist; such agents are of interest for treating Parkinson’s disease, asthma, and other conditions. Xanthine amine congener (XAC) was appended with an alkyne group on an extended C8 substituent for coupling by Cu(I)-catalyzed click chemistry to azide-derivatized G4 (fourth-generation) PAMAM dendrimers to form triazoles. These conjugates also contained triazole-linked PEG groups (8 or 22 moieties per 64 terminal positions) for increasing water-solubility and optionally prosthetic groups for spectroscopic characterization and affinity labeling. Human AR binding affinity increased progressively with the degree of xanthine substitution to reach Ki values in the nM range. The order of affinity of each conjugate was hA2AAR > hA3AR > hA1AR, while the corresponding monomer was ranked hA2AAR > hA1AR ≥ hA3AR. The antagonist activity of the most potent conjugate 14 (34 xanthines per dendrimer) was examined at the Gi-coupled A1AR. Conjugate 14 at 100 nM right-shifted the AR agonist concentration-response curve in a cyclic AMP functional assay in a parallel manner, but at 10 nM (lower than its Ki value) it significantly suppressed the maximal agonist effect in calcium mobilization. This is the first systematic probing of a potent AR antagonist tethered on a dendrimer and its activity as a function of variable loading. PMID:21539392

  13. An Emerging Mycoplasma Associated with Trichomoniasis, Vaginal Infection and Disease

    PubMed Central

    Fettweis, Jennifer M.; Serrano, Myrna G.; Huang, Bernice; Brooks, J. Paul; Glascock, Abigail L.; Sheth, Nihar U.; Strauss, Jerome F.; Jefferson, Kimberly K.; Buck, Gregory A.

    2014-01-01

    Humans are colonized by thousands of bacterial species, but it is difficult to assess the metabolic and pathogenic potential of the majority of these because they have yet to be cultured. Here, we characterize an uncultivated vaginal mycoplasma tightly associated with trichomoniasis that was previously known by its 16S rRNA sequence as “Mnola.” In this study, the mycoplasma was found almost exclusively in women infected with the sexually transmitted pathogen Trichomonas vaginalis, but rarely observed in women with no diagnosed disease. The genomes of four strains of this species were reconstructed using metagenome sequencing and assembly of DNA from four discrete mid-vaginal samples, one of which was obtained from a pregnant woman with trichomoniasis who delivered prematurely. These bacteria harbor several putative virulence factors and display unique metabolic strategies. Genes encoding proteins with high similarity to potential virulence factors include two collagenases, a hemolysin, an O-sialoglycoprotein endopeptidase and a feoB-type ferrous iron transport system. We propose the name “Candidatus Mycoplasma girerdii” for this potential new pathogen. PMID:25337710

  14. An emerging mycoplasma associated with trichomoniasis, vaginal infection and disease.

    PubMed

    Fettweis, Jennifer M; Serrano, Myrna G; Huang, Bernice; Brooks, J Paul; Glascock, Abigail L; Sheth, Nihar U; Strauss, Jerome F; Jefferson, Kimberly K; Buck, Gregory A

    2014-01-01

    Humans are colonized by thousands of bacterial species, but it is difficult to assess the metabolic and pathogenic potential of the majority of these because they have yet to be cultured. Here, we characterize an uncultivated vaginal mycoplasma tightly associated with trichomoniasis that was previously known by its 16S rRNA sequence as "Mnola." In this study, the mycoplasma was found almost exclusively in women infected with the sexually transmitted pathogen Trichomonas vaginalis, but rarely observed in women with no diagnosed disease. The genomes of four strains of this species were reconstructed using metagenome sequencing and assembly of DNA from four discrete mid-vaginal samples, one of which was obtained from a pregnant woman with trichomoniasis who delivered prematurely. These bacteria harbor several putative virulence factors and display unique metabolic strategies. Genes encoding proteins with high similarity to potential virulence factors include two collagenases, a hemolysin, an O-sialoglycoprotein endopeptidase and a feoB-type ferrous iron transport system. We propose the name "Candidatus Mycoplasma girerdii" for this potential new pathogen. PMID:25337710

  15. Identification of major immunogenic proteins of Mycoplasma synoviae isolates.

    PubMed

    Bercic, Rebeka Lucijana; Slavec, Brigita; Lavric, Miha; Narat, Mojca; Bidovec, Andrej; Dovc, Peter; Bencina, Dusan

    2008-02-01

    Mycoplasma synoviae isolates differ in patterns of immunogenic proteins, but most of them have not been identified yet. The main aim of this study was their identification in two closely related M. synoviae isolates, ULB 02/P4 and ULB 02/OV6, recovered recently from chickens in Slovenia. N-terminal sequencing identified 17 M. synoviae proteins. Amongst them were 14 major, highly expressed but previously unidentified proteins, including enzymes, chaperones and putative lipoproteins. ULB 02/P4 proteins with increasing molecular weight (M(w)) in the region above the lipoprotein MSPB (approximately 40 kDa) were elongation factor EF-Tu, enolase, NADH oxidase, haemagglutinin MSPA, ATP synthase beta chain, trigger factor, pyruvate kinase and chaperone DnaK. Enolase (approximately 47 kDa) seemed to be immunogenic for chickens infected with M. synoviae, whereas EF-Tu, which might cross-react with antibodies to the P1 adhesin of Mycoplasma pneumoniae, was not. ULB 02/OV6 synthesized several immunogenic proteins and those with M(w) of approximately 70, 78, 82, 90, 110 and 160 kDa, cross-reacted with antibodies to Mycoplasma gallisepticum. They remain to be identified, because besides putative lipoproteins, protein bands of 78, 82, 85 and 110 kDa contained also dehydrogenase PdhD, elongation factor EF-G, enzyme PtsG and putative neuraminidase, respectively. PMID:17720337

  16. The effects of increasing sodium chloride concentration on Mycoplasma gallisepticum vaccine survival in solution.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lyophilized Mycoplasma gallisepticum (MG) vaccines are generally rehydrated and diluted with distilled or chlorine-free water as per manufacturer recommendations. However, as mycoplasma species lack a cell wall, this can lead to decreased viability of live vaccine during administration. The abilit...

  17. Mycoplasma pneumoniae Pneumonia Associated With Methemoglobinemia and Anemia: An Overlooked Association?

    PubMed Central

    Khoury, Tawfik; Abu Rmeileh, Ayman; Kornspan, Jonathan David; Abel, Roy; Mizrahi, Meir; Nir-Paz, Ran

    2015-01-01

    We report a case of acute methemoglobinemia and anemia in a patient with Mycoplasma pneumoniae pneumonia. We suggest that M. pneumoniae secretes a putative protein that can induce methemoglobin in red blood cells. Thus, Mycoplasma pneumoniae may induce methemoglobinemia in patients who have low oxygen saturation and anemia. PMID:26034771

  18. Suppression of Rous Sarcoma Virus Growth in Tissue Cultures by Mycoplasma orale

    PubMed Central

    Somerson, Norman L.; Cook, M. K.

    1965-01-01

    Somerson, Norman L. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), and M. K. Cook. Suppression of Rous sarcoma virus growth in tissue cultures by Mycoplasma orale. J. Bacteriol. 90:534–540. 1965.—An agent which produced cell destruction in human diploid and chick-embryo fibroblasts was isolated from WI-26 strain of human diploid fibroblasts and shown to be a mycoplasma. The multiplication of Rous sarcoma virus (RSV) and Rous associated virus (RAV) was inhibited in WI-26, WI-38, and chick-embryo fibroblasts infected with this mycoplasma. The mycoplasma isolate, designated strain 941, reacted strongly in the complement-fixation test with antiserum to Mycoplasma orale CH19299, an isolate obtained from the human oral cavity. The cytopathic effect of mycoplasma strain 941 could be eliminated by growing the mycoplasma on an artificial agar medium before inoculation into chick-embryo fibroblasts. Serial passage in chick-embryo fibroblasts restored the cytopathogenicity of the agar-grown mycoplasma. However, growth of RSV and RAV was inhibited by both the tissue culture-grown and the agar-grown 941 strain, and also by the CH19299 strain which did not produce any cytopathic effect. Images PMID:14329470

  19. Cross reactivity among the swine mycoplasmas as identified by protein microarray.

    PubMed

    Petersen, Andrew C; Oneal, David C; Seibel, Janice R; Poel, Kylie; Daum, Courtney L; Djordjevic, Steven P; Minion, F Chris

    2016-08-30

    Mycoplasmas are cell wall-less bacteria that infect a variety of animals in a species-specific manner. In swine, Mycoplasma hyopneumoniae is the most virulent and presents the most disease and economic problems to the swine industry. Serological assays are commonly used to assess colonization and disease, but antigenic cross-reactivity between M. hyopneumoniae and other mycoplasma species, most notably Mycoplasma hyorhinis, Mycoplasma hyosynoviae and Mycoplasma flocculare, is a concern. The extent of cross-reactivity has not been thoroughly investigated. These studies were designed to identify M. hyopneumoniae proteins that are recognized by rabbit hyperimmune sera raised against the other swine mycoplasmas. Our results indicate extensive cross-reactivity between M. flocculare and M. hyopneumoniae, which explains previous reports seen with ELISA assays. Only three of the thirty-nine M. hyopneumoniae proteins tested showed no cross reactivity with the other three swine mycoplasmas, mhp182 (42kDa C-terminal fragment), mhp638 and mhp684 (C-terminal fragment). Two proteins, mhp384 and mhp511, were cross-reactive with hyperimmune sera generated against three of the four species. None of the anti-M. hyorhinis hyperimmune sera reacted to any of the M. hyopneumoniae proteins. These results suggest that inapparent M. flocculare infections could produce positive responses in M. hyopneumoniae serological assays due to cross-reactivity, and that M. hyosynoviae infections are less likely to do so and M. hyorhinis infections unlikely to affect assay results. PMID:27527784

  20. World Health Organization International Standard To Harmonize Assays for Detection of Mycoplasma DNA

    PubMed Central

    Baylis, Sally A.; Hanschmann, Kay-Martin; Montag-Lessing, Thomas; Chudy, Michael; Kreß, Julia; Ulrych, Ursula; Czurda, Stefan; Rosengarten, Renate

    2015-01-01

    Nucleic acid amplification technique (NAT)-based assays (referred to here as NAT assays) are increasingly used as an alternative to culture-based approaches for the detection of mycoplasma contamination of cell cultures. Assay features, like the limit of detection or quantification, vary widely between different mycoplasma NAT assays. Biological reference materials may be useful for harmonization of mycoplasma NAT assays. An international feasibility study included lyophilized preparations of four distantly related mycoplasma species (Acholeplasma laidlawii, Mycoplasma fermentans, M. orale, M. pneumoniae) at different concentrations which were analyzed by 21 laboratories using 26 NAT assays with a qualitative, semiquantitative, or quantitative design. An M. fermentans preparation was shown to decrease the interassay variation when used as a common reference material. The preparation was remanufactured and characterized in a comparability study, and its potency (in NAT-detectable units) across different NATs was determined. The World Health Organization (WHO) Expert Committee on Biological Standardization (ECBS) established this preparation to be the “1st World Health Organization international standard for mycoplasma DNA for nucleic acid amplification technique-based assays designed for generic mycoplasma detection” (WHO Tech Rep Ser 987:42, 2014) with a potency of 200,000 IU/ml. This WHO international standard is now available as a reference preparation for characterization of NAT assays, e.g., for determination of analytic sensitivity, for calibration of quantitative assays in a common unitage, and for defining regulatory requirements in the field of mycoplasma testing. PMID:26070671

  1. Perception of visual apparent motion is modulated by a gap within concurrent auditory glides, even when it is illusory

    PubMed Central

    Wang, Qingcui; Guo, Lu; Bao, Ming; Chen, Lihan

    2015-01-01

    Auditory and visual events often happen concurrently, and how they group together can have a strong effect on what is perceived. We investigated whether/how intra- or cross-modal temporal grouping influenced the perceptual decision of otherwise ambiguous visual apparent motion. To achieve this, we juxtaposed auditory gap transfer illusion with visual Ternus display. The Ternus display involves a multi-element stimulus that can induce either of two different percepts of apparent motion: ‘element motion’ (EM) or ‘group motion’ (GM). In “EM,” the endmost disk is seen as moving back and forth while the middle disk at the central position remains stationary; while in “GM,” both disks appear to move laterally as a whole. The gap transfer illusion refers to the illusory subjective transfer of a short gap (around 100 ms) from the long glide to the short continuous glide when the two glides intercede at the temporal middle point. In our experiments, observers were required to make a perceptual discrimination of Ternus motion in the presence of concurrent auditory glides (with or without a gap inside). Results showed that a gap within a short glide imposed a remarkable effect on separating visual events, and led to a dominant perception of GM as well. The auditory configuration with gap transfer illusion triggered the same auditory capture effect. Further investigations showed that visual interval which coincided with the gap interval (50–230 ms) in the long glide was perceived to be shorter than that within both the short glide and the ‘gap-transfer’ auditory configurations in the same physical intervals (gaps). The results indicated that auditory temporal perceptual grouping takes priority over the cross-modal interaction in determining the final readout of the visual perception, and the mechanism of selective attention on auditory events also plays a role. PMID:26042055

  2. In vitro susceptibilities to fluoroquinolones in current and archived Mycoplasma gallisepticum and Mycoplasma synoviae isolates from meat-type turkeys.

    PubMed

    Gerchman, Irina; Lysnyansky, Inna; Perk, Shimon; Levisohn, Sharon

    2008-10-15

    Monitoring of susceptibility to antibiotics in field isolates of pathogenic avian mycoplasmas is important for appropriate choice of treatment. Our study compared in vitro susceptibility to enrofloxacin and difloxacin in recent (2005-2006) isolates of Mycoplasma gallisepticum and Mycoplasma synoviae from meat-type turkey flocks with archived (1997-2003) isolates and reference strains. Comparison of minimal inhibitory concentration (MIC) values determined by microtest, agar dilution and commercial Etest showed good agreement, but underscored the need for standardized methods for testing. Notably, while the commercial Etest was convenient and accurate for determining MICs for enrofloxacin in the range 0.002-0.094microg/ml, the endpoint of inhibition for M. gallisepticum and M. synoviae strains with MIC values > or =1.0microg/ml could not be determined. A decrease in susceptibility to both fluoroquinolones was detected in archived strains but to a greater degree in recent isolates, most of which had MICs above the NCCLS susceptibility breakpoint for these antibiotics (< or =0.5microg/ml). In contrast, except for one flock, M. synoviae isolates were susceptible, although intrinsically less susceptible than M. gallisepticum. Overall for the 88 strains tested (45 M. gallisepticum, 43 M. synoviae), the MIC50 for both enrofloxacin and difloxacin was 0.5microg/ml. The isolation of fluoroquinolone-resistant M. gallisepticum isolates from breeder and broiler flocks as well as from meat-type turkeys suggests that these strains have become established in Israel, necessitating a reevaluation of antibiotic therapy. Periodic survey of MICs in field isolates of avian mycoplasmas to monitor for the possible appearance of resistant strains is recommended. PMID:18534788

  3. Azithromycin treatment for nongonococcal urethritis negative for Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum.

    PubMed

    Maeda, Shin-ichi; Yasuda, Mitsuru; Ito, Shin; Seike, Kensaku; Ito, Shin-ichi; Deguchi, Takashi

    2009-02-01

    Some patients with nongonococcal urethritis (NGU) are negative for Chlamydia trachomatis, mycoplasmas, and ureaplasmas. The optimal antimicrobial chemotherapy for such NGU has not fully been clarified. We assessed the efficacy of azithromycin for treatment of nonmycoplasmal, nonureaplasmal, nonchlamydial NGU (NMNUNCNGU). Thirty-eight men whose first-pass urine was negative for Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum were treated with a single dose of 1 g azithromycin. Urethritis symptoms and polymorphonuclear leukocytes in urethral smears or in first-pass urine were assessed before and after treatment with azithromycin. Thirty-two (84.2%) of the 38 men with NMNUNCNGU showed no signs of urethral inflammation after treatment. The efficacy of this azithromycin regimen was comparable to that of the 7-day regimen of levofloxacin, gatifloxacin, minocycline, or clarithromycin reported previously. A single dose of 1 g azithromycin, which is effective not only for NGU due to specific pathogens but also for NMNUNCNGU, is an appropriate treatment for NGU. PMID:19228227

  4. Antibody responses of swine following infection with Mycoplasma hyopneumoniae, M. hyorhinis, M. hyosynoviae and M. flocculare.

    PubMed

    Gomes Neto, João Carlos; Strait, Erin L; Raymond, Matthew; Ramirez, Alejandro; Minion, F Chris

    2014-11-01

    Several mycoplasma species possessing a range of virulence have been described in swine. The most commonly described are Mycoplasma hyopneumoniae, Mycoplasma hyorhinis, Mycoplasma hyosynoviae, and Mycoplasma flocculare. They are ubiquitious in many pig producing areas of the world, and except for M. hyopneumoniae, commercial antibody-based assays are lacking for most of these. Antibody cross-reactivity among these four mycoplasma species is not well characterized. Recently, the use of pen-based oral fluids for herd surveillance is of increasing interest. Thus, this study sought to measure pig antibody responses and the level of cross-reactivity in serum and pen-based oral fluids after challenge with four species of swine mycoplasmas. Four groups of four mycoplasma-free growing pigs were separately inoculated with the different mycoplasma species. Pen-based oral fluids and serum samples were collected weekly until necropsy. Species-specific Tween 20 ELISAs were used to measure antibody responses along with four other commercial M. hyopneumoniae ELISAs. Animals from all groups seroconverted to the challenge species of mycoplasma and no evidence of cross-contamination was observed. A delayed antibody response was seen with all but M. hyorhinis-infected pigs. Cross-reactive IgG responses were detected in M. hyopneumoniae- and M. flocculare-infected animals by the M. hyorhinis Tween 20 ELISA, while sera from M. hyosynoviae and M. flocculare-infected pigs were positive in one commercial assay. In pen-based oral fluids, specific anti-M. hyopneumoniae IgA responses were detected earlier after infection than serum IgG responses. In summary, while some antibody-based assays may have the potential for false positives, evidence of this was observed in the current study. PMID:25240775

  5. Molecular characterisation of Mycoplasma species isolated from the genital tract of Dorper sheep in South Africa.

    PubMed

    Kalshingi, Habu A; Bosman, Anna-Mari; Gouws, Johan; van Vuuren, Moritz

    2015-01-01

    Biochemical and molecular analysis were conducted on 34 strains of Mycoplasma species isolated between 2003 and 2009 from the genital tract of clinically healthy Dorper sheep and sheep with ulcerative vulvitis and balanitis. Earlier publications identified the causative agent as Mycoplasma mycoides mycoides large colony (MmmLC) and Arcanobacterium pyogenes. The aims of the study were to characterise Mycoplasma species isolated from the genital tract of Dorper sheep with polymerase chain reaction assay, cloning and gene sequencing. Basic Local Alignment Search Tool (BLAST) results revealed six predominant Mycoplasma species: Mycoplasma arginini, Mycoplasma bovigenitalium, Arcanobacterium laidlawii, MmmLC, Mycoplasma sp. ovine/caprine serogroup II and M. canadense. Sequencing of the 34 isolates were analysed using phylogenetic methods, and 18 (50%) were identified as M. arginini with 99% - 100% similarity to M. arginini from England and Sweden. Six isolates showed 99% similarity to M. bovigenitalium strains from Turkey and Germany. Two isolates had 99% similarity to an M. sp. ovine/caprine sero group II from the United Kingdom. BLAST for two isolates revealed 99% similarity to Acholeplasma laidlawii from India, another two were 99% similar to MmmLC strain from Sweden, two showed 98% similarity to Mycoplasma sp. Usp 120 from Brazil, and two isolates have a 97% - 99% similarity to M. mm. Jcv1 strain from the United States of America. Finally, one isolate showed similarity of 99% to Mycoplasma canadense strain from Italy. The findings support the hypothesis that ulcerative vulvitis and balanitis of Dorper sheep in South Africa (SA) is a multifactorial disease with involvement of different Mycoplasma species. PMID:26244581

  6. Contact- and Protein Transfer-Dependent Stimulation of Assembly of the Gliding Motility Machinery in Myxococcus xanthus

    PubMed Central

    Jakobczak, Beata; Keilberg, Daniela; Wuichet, Kristin; Søgaard-Andersen, Lotte

    2015-01-01

    Bacteria engage in contact-dependent activities to coordinate cellular activities that aid their survival. Cells of Myxococcus xanthus move over surfaces by means of type IV pili and gliding motility. Upon direct contact, cells physically exchange outer membrane (OM) lipoproteins, and this transfer can rescue motility in mutants lacking lipoproteins required for motility. The mechanism of gliding motility and its stimulation by transferred OM lipoproteins remain poorly characterized. We investigated the function of CglC, GltB, GltA and GltC, all of which are required for gliding. We demonstrate that CglC is an OM lipoprotein, GltB and GltA are integral OM β-barrel proteins, and GltC is a soluble periplasmic protein. GltB and GltA are mutually stabilizing, and both are required to stabilize GltC, whereas CglC accumulate independently of GltB, GltA and GltC. Consistently, purified GltB, GltA and GltC proteins interact in all pair-wise combinations. Using active fluorescently-tagged fusion proteins, we demonstrate that GltB, GltA and GltC are integral components of the gliding motility complex. Incorporation of GltB and GltA into this complex depends on CglC and GltC as well as on the cytoplasmic AglZ protein and the inner membrane protein AglQ, both of which are components of the gliding motility complex. Conversely, incorporation of AglZ and AglQ into the gliding motility complex depends on CglC, GltB, GltA and GltC. Remarkably, physical transfer of the OM lipoprotein CglC to a ΔcglC recipient stimulates assembly of the gliding motility complex in the recipient likely by facilitating the OM integration of GltB and GltA. These data provide evidence that the gliding motility complex in M. xanthus includes OM proteins and suggest that this complex extends from the cytoplasm across the cell envelope to the OM. These data add assembly of gliding motility complexes in M. xanthus to the growing list of contact-dependent activities in bacteria. PMID:26132848

  7. Bacterial gliding fluid dynamics on a layer of non-Newtonian slime: Perturbation and numerical study.

    PubMed

    Ali, N; Asghar, Z; Anwar Bég, O; Sajid, M

    2016-05-21

    Gliding bacteria are an assorted group of rod-shaped prokaryotes that adhere to and glide on certain layers of ooze slime attached to a substratum. Due to the absence of organelles of motility, such as flagella, the gliding motion is caused by the waves moving down the outer surface of these rod-shaped cells. In the present study we employ an undulating surface model to investigate the motility of bacteria on a layer of non-Newtonian slime. The rheological behavior of the slime is characterized by an appropriate constitutive equation, namely the Carreau model. Employing the balances of mass and momentum conservation, the hydrodynamic undulating surface model is transformed into a fourth-order nonlinear differential equation in terms of a stream function under the long wavelength assumption. A perturbation approach is adopted to obtain closed form expressions for stream function, pressure rise per wavelength, forces generated by the organism and power required for propulsion. A numerical technique based on an implicit finite difference scheme is also employed to investigate various features of the model for large values of the rheological parameters of the slime. Verification of the numerical solutions is achieved with a variational finite element method (FEM). The computations demonstrate that the speed of the glider decreases as the rheology of the slime changes from shear-thinning (pseudo-plastic) to shear-thickening (dilatant). Moreover, the viscoelastic nature of the slime tends to increase the swimming speed for the shear-thinning case. The fluid flow in the pumping (generated where the organism is not free to move but instead generates a net fluid flow beneath it) is also investigated in detail. The study is relevant to marine anti-bacterial fouling and medical hygiene biophysics. PMID:26903204

  8. Nanoscale Visualization of a Fibrillar Array in the Cell Wall of Filamentous Cyanobacteria and Its Implications for Gliding Motility▿

    PubMed Central

    Read, Nicholas; Connell, Simon; Adams, David G.

    2007-01-01

    Many filamentous cyanobacteria are motile by gliding, which requires attachment to a surface. There are two main theories to explain the mechanism of gliding. According to the first, the filament is pushed forward by small waves that pass along the cell surface. In the second, gliding is powered by the extrusion of slime through pores surrounding each cell septum. We have previously shown that the cell walls of several motile cyanobacteria possess an array of parallel fibrils between the peptidoglycan and the outer membrane and have speculated that the function of this array may be to generate surface waves to power gliding. Here, we report on a study of the cell surface topography of two morphologically different filamentous cyanobacteria, using field emission gun scanning electron microscopy (FEGSEM) and atomic force microscopy (AFM). FEGSEM and AFM images of Oscillatoria sp. strain A2 confirmed the presence of an array of fibrils, visible as parallel corrugations on the cell surface. These corrugations were also visualized by AFM scanning of fully hydrated filaments under liquid; this has not been achieved before for filamentous bacteria. FEGSEM images of Nostoc punctiforme revealed a highly convoluted, not parallel, fibrillar array. We conclude that an array of parallel fibrils, beneath the outer membrane of Oscillatoria, may function in the generation of thrust in gliding motility. The array of convoluted fibrils in N. punctiforme may have an alternative function, perhaps connected with the increase in outer membrane surface area resulting from the presence of the fibrils. PMID:17693519

  9. Effect of curing time and concentration for a chemical treatment that improves surface gliding for extrasynovial tendon grafts in vitro

    PubMed Central

    Tanaka, Toshikazu; Sun, Yu-Long; Zhao, Chunfeng; Zobitz, Mark E.; An, Kai-Nan; Amadio, Peter C.

    2013-01-01

    The purpose of this study was to evaluate whether treatment time and concentration of these reagents have an effect on the resulting gliding resistance. Forty peroneus longus (PL) tendons were used, from 20 adult mongrel dogs, along with the A2 pulley obtained from the ipsilateral hind paw. After the baseline gliding resistance was measured, the PL tendons were treated with one of three concentrations of hyaluronic acid (HA) and 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC) or N-hydroxysuccinimide (NHS) mixed with 10% gelatin for various times (5, 30, and 60 min). Tendon friction was measured over 1000 cycles of simulated flexion/extension motion. Gliding resistance of the untreated PL tendons had no significant difference among the groups. After surface treatment with low concentration of HA and EDC/NHS for 5-min cure, the gliding resistance was similar to that of the untreated PL tendon and significantly higher than its 30- and 60-min treatment. For the rest of high concentration of HA and EDC/NHS groups, the gliding resistance was lower than that of untreated PL tendon. However, there was no significant difference among the timing points. It is possible to optimize the effect of surface treatment on friction and durability by regulating cure time and concentration of reagents in a canine extrasynovial tendon in vitro. PMID:16752399

  10. Development and Host Compatibility of Plasmids for Two Important Ruminant Pathogens, Mycoplasma bovis and Mycoplasma agalactiae

    PubMed Central

    Sharma, Shukriti; Citti, Chistine; Sagné, Eveline; Marenda, Marc S.

    2015-01-01

    Mycoplasma bovis is a cause of pneumonia, mastitis, arthritis and otitis media in cattle throughout the world. However, despite its clinical significance, there is a paucity of tools to genetically manipulate it, impeding our capacity to further explore the molecular basis of its virulence. To address this limitation, we developed a series of homologous and heterologous replicable plasmids from M. bovis and M. agalactiae. The shortest replicable oriC plasmid based on the region downstream of dnaA in M. bovis was 247 bp and contained two DnaA boxes, while oriC plasmids based on the region downstream of dnaA in M. agalactiae strains 5632 and PG2 were 219 bp and 217 bp in length, respectively, and contained only a single DnaA box. The efficiency of transformation in M. bovis and M. agalactiae was inversely correlated with the size of the oriC region in the construct, and, in general, homologous oriC plasmids had a higher transformation efficiency than heterologous oriC plasmids. The larger pWholeoriC45 and pMM21-7 plasmids integrated into the genomic oriC region of M. bovis, while the smaller oriC plasmids remained extrachromosomal for up to 20 serial passages in selective media. Although specific gene disruptions were not be achieved in M. bovis in this study, the oriC plasmids developed here could still be useful as tools in complementation studies and for expression of exogenous genes in both M. bovis and M. agalactiae. PMID:25746296

  11. Decomposition of CCl4 and CHCl3 on gliding are plasma.

    PubMed

    Indarto, Antonius; Choi, Jae-Wook; Lee, Hwaung; Song, Hyung-Keun

    2006-01-01

    Decomposition of chlorinated hydrocarbons, CCl4 and CHCl3, in gliding plasma was examined. The effects of initial concentrations, total gas flow rates, and power consumption have been investigated. The conversion result was relatively high. It reached 80% for CCl4 and 97% for CHCl3. Using atmospheric air as the carrier gas, the plasma reaction occurred at exothermic reaction and the main products were CO2, CO, and Cl2. Transformation into CCl4 was also detected for CHCl3 decomposition reaction. The conversion of CCl4 and CHCl3 were increased with the increasing applied frequency and decreasing total gas flow rate. PMID:20050553

  12. Research on motion model for the hypersonic boost-glide aircraft

    NASA Astrophysics Data System (ADS)

    Xu, Shenda; Wu, Jing; Wang, Xueying

    2015-11-01

    A motion model for the hypersonic boost-glide aircraft(HBG) was proposed in this paper, which also analyzed the precision of model through simulation. Firstly the trajectory of HBG was analyzed, and a scheme which divide the trajectory into two parts then build the motion model on each part. Secondly a restrained model of boosting stage and a restrained model of J2 perturbation were established, and set up the observe model. Finally the analysis of simulation results show the feasible and high-accuracy of the model, and raise a expectation for intensive research.

  13. A 3D model of a reverse vortex flow gliding arc reactor

    NASA Astrophysics Data System (ADS)

    Trenchev, G.; Kolev, St.; Bogaerts, A.

    2016-06-01

    In this computational study, a gliding arc plasma reactor with a reverse-vortex flow stabilization is modelled for the first time by a fluid plasma description. The plasma reactor operates with argon gas at atmospheric pressure. The gas flow is simulated using the k-ε Reynolds-averaged Navier–Stokes turbulent model. A quasi-neutral fluid plasma model is used for computing the plasma properties. The plasma arc movement in the reactor is observed, and the results for the gas flow, electrical characteristics, plasma density, electron temperature, and gas temperature are analyzed.

  14. Emergent spinless Weyl semimetals between the topological crystalline insulator and normal insulator phases with glide symmetry

    NASA Astrophysics Data System (ADS)

    Kim, Heejae; Murakami, Shuichi

    2016-05-01

    We construct a theory describing phase transitions between the spinless topological crystalline insulator phase with glide symmetry and a normal insulator phase. We show that a spinless Weyl semimetal phase should intervene between these two phases. Here, because all the bands are free from degeneracy in general, a gap closing between a single conduction band and a single valence band at phase transition generally gives rise to a pair creation of Weyl nodes; hence the Weyl semimetal phase naturally appears. We show the relationship between the change of the Z2 topological number when the system goes through the Weyl semimetal phase, and the trajectory of the Weyl nodes.

  15. Use-Dependent Curvature Changes in the GlideRite® Reusable Intubation Stylet.

    PubMed

    Smith, Cameron R; Urdaneta, Felipe; Gravenstein, Nikolaus

    2016-05-15

    The Glidescope® is one of the most widely used video laryngoscopes in the market. It is often used with a purpose-built, reusable, "nonmalleable" stainless steel stylet, the GlideRite®. In this study, we investigated whether this stylet retains its original curvature with repeated use and sterilization. To evaluate the shape and curvature of the stylets, high-resolution digital photographs were made of 55 GlideRite stylets (5 new and 50 randomly selected from operating room stock) laid on a grid background and analyzed using Adobe Photoshop®. In a similar fashion, 1 new stylet was inserted into and removed 100 times from an endotracheal tube and photographed every 20 cycles to determine the impact of use on stylet shape. For the 5 new stylets, the handle-to-tip angle was very consistent (23.44° ± 1.04°). The stylets in clinical use varied widely in their configuration. For analysis, they were divided into 3 groups based on the handle-to-tip angle: ±1 SD of the new stylets, those with a shallower angle (straighter), and those with a steeper angle (more curved). The handle-to-tip angles were as follows: 23.07° ± 0.80° (±1 SD), 18.39° ± 2.59° (straighter), and 27.65° ± 2.73° (more curved). Analysis of variance showed that the new and ±1 SD groups were not significantly different, but both the straighter (P = 0.0002) and more curved (P = 0.0048) groups were significantly different from new. The repeated insertion and removal of a new stylet resulted in gradual straightening of the curve of the stylet from 22° at baseline to 19.2° after 100 insertion/removal cycles. Used GlideRite reusable stylets are not reliably equivalent to new ones in terms of their shape or curvature. Given that the repeated insertion and removal of a new stylet from an endotracheal tube resulted in their straightening, it is likely that clinical use has the same effect. Because many used stylets were actually more curved than the new ones, we hypothesize that practitioners

  16. Rapid diffusion of magic-size islands by combined glide and vacancy mechanisms

    SciTech Connect

    Perez, D; Voter, A F; Uche, O U; Hamilton, J C

    2009-01-01

    Using molecular dynamics, nudged elastic band, and embedded atom methods, we show that certain 2D Ag islands undergo extremely rapid one-dimensional diffusion on Cu(001) surfaces. Indeed, below 300K, hopping rates for 'magic-size' islands are orders of magnitude faster than hopping rates for single Ag adatoms. This rapid diffusion requires both the c(10 x 2) hexagonally-packed superstructure typical of Ag on Cu(001) and appropriate 'magic-sizes' for the islands. The novel highly-cooperative diffusion mechanism presented here couples vacancy diffusion with simultaneous core glide.

  17. The mysterious nature of bacterial surface (gliding) motility: A focal adhesion-based mechanism in Myxococcus xanthus.

    PubMed

    Islam, Salim T; Mignot, Tâm

    2015-10-01

    Motility of bacterial cells promotes a range of important physiological phenomena such as nutrient detection, harm avoidance, biofilm formation, and pathogenesis. While much research has been devoted to the mechanism of bacterial swimming in liquid via rotation of flagellar filaments, the mechanisms of bacterial translocation across solid surfaces are poorly understood, particularly when cells lack external appendages such as rotary flagella and/or retractile type IV pili. Under such limitations, diverse bacteria at the single-cell level are still able to "glide" across solid surfaces, exhibiting smooth translocation of the cell along its long axis. Though multiple gliding mechanisms have evolved in different bacterial classes, most remain poorly characterized. One exception is the gliding motility mechanism used by the Gram-negative social predatory bacterium Myxococcus xanthus. The available body of research suggests that M. xanthus gliding motility is mediated by trafficked multi-protein (Glt) cell envelope complexes, powered by proton-driven flagellar stator homologues (Agl). Through coupling to the substratum via polysaccharide slime, Agl-Glt assemblies can become fixed relative to the substratum, forming a focal adhesion site. Continued directional transport of slime-associated substratum-fixed Agl-Glt complexes would result in smooth forward movement of the cell. In this review, we have provided a comprehensive synthesis of the latest mechanistic and structural data for focal adhesion-mediated gliding motility in M. xanthus, with emphasis on the role of each Agl and Glt protein. Finally, we have also highlighted the possible connection between the motility complex and a new type of spore coat assembly system, suggesting that gliding and cell envelope synthetic complexes are evolutionarily linked. PMID:26520023

  18. Genomic characterization of symbiotic mycoplasmas from the stomach of deep-sea isopod bathynomus sp.

    PubMed

    Wang, Yong; Huang, Jiao-Mei; Wang, Shao-Lu; Gao, Zhao-Ming; Zhang, Ai-Qun; Danchin, Antoine; He, Li-Sheng

    2016-09-01

    Deep-sea isopod scavengers such as Bathynomus sp. are able to live in nutrient-poor environments, which is likely attributable to the presence of symbiotic microbes in their stomach. In this study we recovered two draft genomes of mycoplasmas, Bg1 and Bg2, from the metagenomes of the stomach contents and stomach sac of a Bathynomus sp. sample from the South China Sea (depth of 898 m). Phylogenetic trees revealed a considerable genetic distance to other mycoplasma species for Bg1 and Bg2. Compared with terrestrial symbiotic mycoplasmas, the Bg1 and Bg2 genomes were enriched with genes encoding phosphoenolpyruvate-dependent phosphotransferase systems (PTSs) and sodium-driven symporters responsible for the uptake of sugars, amino acids and other carbohydrates. The genome of mycoplasma Bg1 contained sialic acid lyase and transporter genes, potentially enabling the bacteria to attach to the stomach sac and obtain organic carbons from various cell walls. Both of the mycoplasma genomes contained multiple copies of genes related to proteolysis and oligosaccharide degradation, which may help the host survive in low-nutrient conditions. The discovery of the different types of mycoplasma bacteria in the stomach of this deep-sea isopod affords insights into symbiotic model of deep-sea animals and genomic plasticity of mycoplasma bacteria. PMID:27312602

  19. Molecular detection and prevalence of feline hemotropic mycoplasmas in Istanbul, Turkey.

    PubMed

    Cetinkaya, Handan; Haktanir, Damla; Arun, Seckin; Vurusaner, Cem

    2016-01-01

    The aim of this study was to investigate Mycoplasma spp. species in blood samples of the domestic cats from the province of Istanbul, Turkey. Three hundred eighty four blood samples of client-owned cats were used for the identification of Mycoplasma haemofelis (Mhf), Candidatus Mycoplasma haemominutum (CMhm) and Candidatus Mycoplasma turicensis (CMt) by Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) assays. Out of 384 blood samples, 74 (19.3%) were positive for one of Mycoplasma species. The total prevalence of Mhf, CMhm and CMt infections was 9.9%, 17.7% and 0.8% respectively. The most common species was CMhm. Co-infections were mostly with Mhf/CMhm and the frequency was 8.1%. Two cats were infected with three species. The current study was the first molecular prevalence study of hemotropic mycoplasmas in Istanbul, reporting the presence of CMt for the first time in Turkey. Prevalence of feline mycoplasma was notably high in Istanbul and PCR assay could be preferred rather than the microscopic examination for the diagnosis. PMID:26751888

  20. Heart rate and estimated energy expenditure of flapping and gliding in black-browed albatrosses.

    PubMed

    Sakamoto, Kentaro Q; Takahashi, Akinori; Iwata, Takashi; Yamamoto, Takashi; Yamamoto, Maki; Trathan, Philip N

    2013-08-15

    Albatrosses are known to expend only a small amount of energy during flight. The low energy cost of albatross flight has been attributed to energy-efficient gliding (soaring) with sporadic flapping, although little is known about how much time and energy albatrosses expend in flapping versus gliding during cruising flight. Here, we examined the heart rates (used as an instantaneous index of energy expenditure) and flapping activities of free-ranging black-browed albatrosses (Thalassarche melanophrys) to estimate the energy cost of flapping as well as time spent in flapping activities. The heart rate of albatrosses during flight (144 beats min(-1)) was similar to that while sitting on the water (150 beats min(-1)). In contrast, heart rate was much higher during takeoff and landing (ca. 200 beats min(-1)). Heart rate during cruising flight was linearly correlated with the number of wing flaps per minute, suggesting an extra energy burden of flapping. Albatrosses spend only 4.6±1.4% of their time flapping during cruising flight, which was significantly lower than during and shortly after takeoff (9.8±3.5%). Flapping activity, which amounted to just 4.6% of the time in flight, accounted for 13.3% of the total energy expenditure during cruising flight. These results support the idea that albatrosses achieve energy-efficient flight by reducing the time spent in flapping activity, which is associated with high energy expenditure. PMID:23661772

  1. CO2 Dissociation by Low Current Gliding Discharge in the Reverse Vortex Flow

    NASA Astrophysics Data System (ADS)

    Gutsol, Alexander

    2012-10-01

    If performed with high energy efficiency, plasma-chemical dissociation of carbon dioxide can be a way of converting and storing energy when there is an excess of electric energy, for example generated by solar elements of wind turbines. CO2 dissociation with efficiency of up to 90% was reported earlier for low pressure microwave discharge in supersonic flow. A new plasma-chemical system uses a low current gliding discharge in the reverse vortex flow of plasma gas. The system is a development of the Gliding Arc in Tornado reactor. The system was used to study dissociation of CO2 in wide ranges of the following experimental parameters: reactor pressure (15-150 kPa), discharge current (50-500 mA), gas flow rate (3-30 liters per minute), and electrode gap length (1-10 cm). Additionally, the effect of thermal energy recuperation on CO2 dissociation efficiency was tested. Plasma chemical efficiency of CO2 dissociation is very low (about 3%) in a short discharge at low pressures (about 15 kPa) when it is defined by electronic excitation. The highest efficiency (above 40%) was reached at pressures 50-70 kPa in a long discharge with thermal energy recuperation. It means that the process is controlled by thermal dissociation with subsequent effective quenching. Plasma chemical efficiency was determined from the data of chromatographic analysis and oscilloscope electric power integration, and also was checked calorimetrically by the thermal balance of the system.

  2. The novel marine gliding zooflagellate genus Mantamonas (Mantamonadida ord. n.: Apusozoa).

    PubMed

    Glücksman, Edvard; Snell, Elizabeth A; Berney, Cédric; Chao, Ema E; Bass, David; Cavalier-Smith, Thomas

    2011-04-01

    Mantamonasis a novel genus of marine gliding zooflagellates probably related to apusomonad and planomonad Apusozoa. Using phase and differential interference contrast microscopy we describe the type species Mantamonas plasticasp. n. from coastal sediment in Cumbria, England. Cells are ∼5μm long, ∼5μm wide, asymmetric, flattened, biciliate, and somewhat plastic. The posterior cilium, on which they glide smoothly over the substratum, is long and highly acronematic. The much thinner, shorter, and almost immobile anterior cilium points forward to the cell's left. These morphological and behavioural traits suggest thatMantamonasis a member of the protozoan phylum Apusozoa. Analyses of 18S and 28S rRNA gene sequences of Mantamonas plasticaand a second genetically very different marine species from coastal sediment in Tanzania show Mantamonasas a robustly monophyletic clade, that is very divergent from all other eukaryotes. 18S rRNA trees mostly placeMantamonaswithin unikonts (opisthokonts, Apusozoa, and Amoebozoa) but its precise position varies with phylogenetic algorithm and/or taxon and nucleotide position sampling; it may group equally weakly as sister to Planomonadida, Apusomonadida or Breviata. On 28S rRNA and joint 18/28S rRNA phylogenies (including 11 other newly obtained apusozoan/amoebozoan 28S rRNA sequences) it consistently strongly groups with Apusomonadida (Apusozoa). PMID:20884290

  3. Development of a gliding arc plasma reactor for CO₂destruction.

    PubMed

    Kim, Seong Cheon; Chun, Young Nam

    2014-01-01

    A gliding arc plasma reactor was designed to destruct carbon dioxide (CO₂), which is a major greenhouse gas. To increase the CO₂destruction rate with a high processing gas volume, an orifice baffle for gathering the gas flow at the centre of the electrodes was installed in the gliding arc plasma reactor. The CO₂inflows with methane (CH₄) and steam (H₂O) improve the CO₂destruction. The parametric studies have been made of the change of CH4 addition, gas injection velocity of the centre nozzle, change of CO₂gas flow rate, and orifice baffle configuration. The produced gases were measured, and the data analysis has been achieved in determining the CO₂destruction rate, CH₄conversion rate, destruction energy efficiency, and selectivity for CO₂and H₂. The highest CO₂ destruction rate for each parameter has been shown as follows: the CH₄/CO₂ratio is 1 as 40%, and the injection gas velocity is 69.5 m/s as 35.7%, the CO₂flow rate is 5 L/min as 42.6%, and the orifice baffle is Type 1, which had the smallest internal area, as 35.7%. PMID:25189841

  4. Atomistic study on the generation and gliding properties of pyramidal dislocations in magnesium

    NASA Astrophysics Data System (ADS)

    Kaburaki, Hideo; Itakura, Mitsuhiro; Yamaguchi, Masatake

    Plastic deformation of magnesium and its alloys is attracting great interest as one of the candidate materials for energy-conserving lightweight structural metals. The generation of non-basal pyramidal dislocations near the c-axis direction is the key to enhancing plasticity in these highly anisotropic hcp magnesium materials. However, the fundamental understanding of the generation and gliding properties of pyramidal dislocations is still not clear because of the large Burgers vector. Using the molecular dynamics method, we have successfully generated < c + a > type I and II screw dislocations from the crack set in the perfect magnesium crystal by applying the shear stress. Visualization of these dislocations is important because the core structures are complex and largely extended. Comparing the results by first-principles calculations, we have found that the core of the type I screw dislocation is smoothly extended while that of the type II screw dislocation has a corrugated structure. We also found that both dislocations can easily cross-slip to other slip planes. In particular, it is observed that the core of the gliding pyramidal type I screw dislocation cross-slips to other slip planes. The detailed processes of cross-slip are elucidated in the presentation.

  5. A protein secretion system linked to bacteroidete gliding motility and pathogenesis.

    PubMed

    Sato, Keiko; Naito, Mariko; Yukitake, Hideharu; Hirakawa, Hideki; Shoji, Mikio; McBride, Mark J; Rhodes, Ryan G; Nakayama, Koji

    2010-01-01

    Porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. Protein secretion systems common to other Gram-negative bacteria are lacking in P. gingivalis, but several proteins, including PorT, have been linked to gingipain secretion. Comparative genome analysis and genetic experiments revealed 11 additional proteins involved in gingipain secretion. Six of these (PorK, PorL, PorM, PorN, PorW, and Sov) were similar in sequence to Flavobacterium johnsoniae gliding motility proteins, and two others (PorX and PorY) were putative two-component system regulatory proteins. Real-time RT-PCR analysis revealed that porK, porL, porM, porN, porP, porT, and sov were down-regulated in P. gingivalis porX and porY mutants. Disruption of the F. johnsoniae porT ortholog resulted in defects in motility, chitinase secretion, and translocation of a gliding motility protein, SprB adhesin, to the cell surface, providing a link between a unique protein translocation system and a motility apparatus in members of the Bacteroidetes phylum. PMID:19966289

  6. The Effects of One-Dimensional Glide On the Reaction Kinetics of Interstitial Clusters

    SciTech Connect

    Heinisch, Howard L.; Singh, B. N.; Golubov, S. I.

    2000-09-01

    Collision cascades in metals produce small interstitial clusters and perfect dislocation loops that glide in thermally activated, one-dimensional (1D) random walks. These gliding defects can change their Burgers vectors by thermal activation or by interactions with other defects. Their migration is therefore ?mixed 1D/3D migration? along a 3D path consisting of 1D segments. The defect reaction kinetics under mixed 1D/3D diffusion are different from both pure 1D diffusion and pure 3D diffusion, both of which can be formulated within analytical rate theory models of microstructure evolution under irradiation. Atomic-scale Kinetic Monte Carlo defect migration simulations are used to investigate the effects of mixed 1D/3D migration on defect reaction kinetics as a guide for implementing mixed 1D/3D migration into the theory. The dependence of sink strength on the size and concentration of sinks under mixed 1D/3D migration lies between those for pure 1D and pure 3D migration and varies with the average distance between direction changes, L. The sink strength for sinks of size R under mixed 1D/3D migration can be approximated by an expression that varies directly as R2 for values of L greater than the sink size. The transition from mixed 1D/3D to pure 3D diffusion as L decreases is demonstrated in the simulations.

  7. Glass micro-wire tracks for guiding kinesin-powered gliding motion of microtubules

    NASA Astrophysics Data System (ADS)

    Kim, K.; Liao, A. L.; Sikora, A.; Oliveira, D.; Umetsu, M.; Kumagai, I.; Adschiri, T.; Hwang, W.; Teizer, W.

    2013-03-01

    Kinesin, an enzyme molecule found in eukaryotic cells, walks on specific paths, namely microtubules. These microtubules, self-assembled in-vitro, cooperate with kinesin molecules by playing the role of either a track for the molecular motors or a lengthy cargo lorry driven by the motor molecules. One of major challenges in utilization of the latter case, which is particularly advantageous for practical applications because of the longer cruising range and the higher carrying capacity of the bio-transporter, is herding the gliding microtubules. A general approach to achieve this goal is aligning motor molecules along a track. In previous attempts such tracks were physically and/or chemically patterned on a glass surface. We use a kinesin-coated glass wire to demonstrate kinesin-powered gliding movement of microtubules confined by the wire-like structure. This new approach distinguishes itself in that the glass wire track is an independent entity, being separable from a two-dimensional surface in principle. We will also discuss quantitative analysis of the guided motility and potential applications.

  8. A protein secretion system linked to bacteroidete gliding motility and pathogenesis

    PubMed Central

    Sato, Keiko; Naito, Mariko; Yukitake, Hideharu; Hirakawa, Hideki; Shoji, Mikio; McBride, Mark J.; Rhodes, Ryan G.; Nakayama, Koji

    2009-01-01

    Porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. Protein secretion systems common to other Gram-negative bacteria are lacking in P. gingivalis, but several proteins, including PorT, have been linked to gingipain secretion. Comparative genome analysis and genetic experiments revealed 11 additional proteins involved in gingipain secretion. Six of these (PorK, PorL, PorM, PorN, PorW, and Sov) were similar in sequence to Flavobacterium johnsoniae gliding motility proteins, and two others (PorX and PorY) were putative two-component system regulatory proteins. Real-time RT-PCR analysis revealed that porK, porL, porM, porN, porP, porT, and sov were down-regulated in P. gingivalis porX and porY mutants. Disruption of the F. johnsoniae porT ortholog resulted in defects in motility, chitinase secretion, and translocation of a gliding motility protein, SprB adhesin, to the cell surface, providing a link between a unique protein translocation system and a motility apparatus in members of the Bacteroidetes phylum. PMID:19966289

  9. Two Essential Light Chains Regulate the MyoA Lever Arm To Promote Toxoplasma Gliding Motility

    PubMed Central

    Williams, Melanie J.; Alonso, Hernan; Enciso, Marta; Egarter, Saskia; Sheiner, Lilach; Meissner, Markus; Striepen, Boris; Smith, Brian J.

    2015-01-01

    ABSTRACT Key to the virulence of apicomplexan parasites is their ability to move through tissue and to invade and egress from host cells. Apicomplexan motility requires the activity of the glideosome, a multicomponent molecular motor composed of a type XIV myosin, MyoA. Here we identify a novel glideosome component, essential light chain 2 (ELC2), and functionally characterize the two essential light chains (ELC1 and ELC2) of MyoA in Toxoplasma. We show that these proteins are functionally redundant but are important for invasion, egress, and motility. Molecular simulations of the MyoA lever arm identify a role for Ca2+ in promoting intermolecular contacts between the ELCs and the adjacent MLC1 light chain to stabilize this domain. Using point mutations predicted to ablate either the interaction with Ca2+ or the interface between the two light chains, we demonstrate their contribution to the quality, displacement, and speed of gliding Toxoplasma parasites. Our work therefore delineates the importance of the MyoA lever arm and highlights a mechanism by which this domain could be stabilized in order to promote invasion, egress, and gliding motility in apicomplexan parasites. PMID:26374117

  10. Concerted Action of Two Formins in Gliding Motility and Host Cell Invasion by Toxoplasma gondii

    PubMed Central

    Daher, Wassim; Plattner, Fabienne; Carlier, Marie-France; Soldati-Favre, Dominique

    2010-01-01

    The invasive forms of apicomplexan parasites share a conserved form of gliding motility that powers parasite migration across biological barriers, host cell invasion and egress from infected cells. Previous studies have established that the duration and direction of gliding motility are determined by actin polymerization; however, regulators of actin dynamics in apicomplexans remain poorly characterized. In the absence of a complete ARP2/3 complex, the formin homology 2 domain containing proteins and the accessory protein profilin are presumed to orchestrate actin polymerization during host cell invasion. Here, we have undertaken the biochemical and functional characterization of two Toxoplasma gondii formins and established that they act in concert as actin nucleators during invasion. The importance of TgFRM1 for parasite motility has been assessed by conditional gene disruption. The contribution of each formin individually and jointly was revealed by an approach based upon the expression of dominant mutants with modified FH2 domains impaired in actin binding but still able to dimerize with their respective endogenous formin. These mutated FH2 domains were fused to the ligand-controlled destabilization domain (DD-FKBP) to achieve conditional expression. This strategy proved unique in identifying the non-redundant and critical roles of both formins in invasion. These findings provide new insights into how controlled actin polymerization drives the directional movement required for productive penetration of parasites into host cells. PMID:20949068

  11. Latest Sea-Operations in the Macaronesian region with Unmanned Autonomous Marine Gliding Vehicles

    NASA Astrophysics Data System (ADS)

    Barrera, Carlos; Lorenzo, Alvaro; Viera, Josue; Morales, Tania; Vega, Daura; Rueda, Maria Jose; Llinas, Octavio

    2013-04-01

    Current advances on key marine technology fields provide nowadays a broad range of autonomous unmanned platforms addressed for an efficient and cost-effective ocean observation, with a suitable level of success in terms of endurance, reliability and useful gathered information. In this context, a multidisciplinary family of unmanned autonomous vehicles addressed to monitor both coastal and open-ocean areas plays a relevant role. During the last month, some of the newest unmanned gliding vehicle technologies have been tested within the context of the Oceanic Platform of the Canary Islands (PLOCAN) in varied operational scenarios aiming different technical and scientific purposes, all of them joined in direct partnership with the company provider and other R&D institutions in some cases. Among others, representative examples in this way are the missions under the name Challenger One, Vulcano and SB02 through surface and underwater gliding vehicles, performed mostly in the surrounding subtropical waters of the ESTOC site observatory in the Canary Islands archipelago. The main gathered operational and scientific results from these missions are presented in this work as a sign of new ocean observing technologies within the framework of the Macaronesian Marine and Maritime Observation Strategy (R3M) and linked with the current European rules programs and projects in this field. Keywords: autonomous vehicle, gliders, R3M, ocean observatory, monitoring, marine robotics, ESTOC,

  12. Energy Management of Manned Boost-Glide Vehicles: A Historical Perspective

    NASA Technical Reports Server (NTRS)

    Day, Richard E.

    2004-01-01

    As flight progressed from propellers to jets to rockets, the propulsive energy grew exponentially. With the development of rocket-only boosted vehicles, energy management of these boost-gliders became a distinct requirement for the unpowered return to base, alternate landing site, or water-parachute landing, starting with the X-series rocket aircraft and terminating with the present-day Shuttle. The problem presented here consists of: speed (kinetic energy) - altitude (potential energy) - steep glide angles created by low lift-to-drag ratios (L/D) - distance to landing site - and the bothersome effects of the atmospheric characteristics varying with altitude. The primary discussion regards post-boost, stabilized glides; however, the effects of centrifugal and geopotential acceleration are discussed as well. The aircraft and spacecraft discussed here are the X-1, X-2, X-15, and the Shuttle; and to a lesser, comparative extent, Mercury, Gemini, Apollo, and lifting bodies. The footprints, landfalls, and methods developed for energy management are also described. The essential tools required for energy management - simulator planning, instrumentation, radar, telemetry, extended land or water range, Mission Control Center (with specialist controllers), and emergency alternate landing sites - were first established through development of early concepts and were then validated by research flight tests.

  13. Pitch glide effect induced by a nonlinear string-barrier interaction

    NASA Astrophysics Data System (ADS)

    Kartofelev, Dmitri; Stulov, Anatoli; Välimäki, Vesa

    2015-10-01

    Interactions of a vibrating string with its supports and other spatially distributed barriers play a significant role in the physics of many stringed musical instruments. It is well known that the tone of the string vibrations is determined by the string supports, and that the boundary conditions of the string termination may cause a short-lasting initial fundamental frequency shifting. Generally, this phenomenon is associated with the nonlinear modulation of the stiff string tension. The aim of this paper is to study the initial frequency glide phenomenon that is induced only by the string-barrier interaction, apart from other possible physical causes, and without the interfering effects of dissipation and dispersion. From a numerical simulation perspective, this highly nonlinear problem may present various difficulties, not the least of which is the risk of numerical instability. We propose a numerically stable and a purely kinematic model of the string-barrier interaction, which is based on the travelling wave solution of the ideal string vibration. The model is capable of reproducing the motion of the vibrating string exhibiting the initial fundamental frequency glide, which is caused solely by the complex nonlinear interaction of the string with its termination. The results presented in this paper can expand our knowledge and understanding of the timbre evolution and the physical principles of sound generation of numerous stringed instruments, such as lutes called the tambura, sitar and biwa.

  14. Effect of cellular filamentation on adventurous and social gliding motility of Myxococcus xanthus

    PubMed Central

    Sun, Hong; Yang, Zhaomin; Shi, Wenyuan

    1999-01-01

    Filamentous bacterial cells often provide biological information that is not readily evident in normal-size cells. In this study, the effect of cellular filamentation on gliding motility of Myxococcus xanthus, a Gram-negative social bacterium, was investigated. Elongation of the cell body had different effects on adventurous and social motility of M. xanthus. The rate of A-motility was insensitive to cell-body elongation whereas the rate of S-motility was reduced dramatically as the cell body got longer, indicating that these two motility systems work in different ways. The study also showed that filamentous wild-type cells glide smoothly with relatively straight, long cell bodies. However, filamentous cells of certain social motility mutants showed zigzag, tangled cell bodies on a solid surface, apparently a result of a lack of coordination between different fragments within the filaments. Further genetic and biochemical analyses indicated that the uncoordinated movements of these mutant filaments were correlated with the absence of cell surface fibril materials, indicating a possible new function for fibrils. PMID:10611358

  15. Velocity Fluctuations in Kinesin-1 Gliding Motility Assays Originate in Motor Attachment Geometry Variations.

    PubMed

    Palacci, Henri; Idan, Ofer; Armstrong, Megan J; Agarwal, Ashutosh; Nitta, Takahiro; Hess, Henry

    2016-08-01

    Motor proteins such as myosin and kinesin play a major role in cellular cargo transport, muscle contraction, cell division, and engineered nanodevices. Quantifying the collective behavior of coupled motors is critical to our understanding of these systems. An excellent model system is the gliding motility assay, where hundreds of surface-adhered motors propel one cytoskeletal filament such as an actin filament or a microtubule. The filament motion can be observed using fluorescence microscopy, revealing fluctuations in gliding velocity. These velocity fluctuations have been previously quantified by a motional diffusion coefficient, which Sekimoto and Tawada explained as arising from the addition and removal of motors from the linear array of motors propelling the filament as it advances, assuming that different motors are not equally efficient in their force generation. A computational model of kinesin head diffusion and binding to the microtubule allowed us to quantify the heterogeneity of motor efficiency arising from the combination of anharmonic tail stiffness and varying attachment geometries assuming random motor locations on the surface and an absence of coordination between motors. Knowledge of the heterogeneity allows the calculation of the proportionality constant between the motional diffusion coefficient and the motor density. The calculated value (0.3) is within a standard error of our measurements of the motional diffusion coefficient on surfaces with varying motor densities calibrated by landing rate experiments. This allowed us to quantify the loss in efficiency of coupled molecular motors arising from heterogeneity in the attachment geometry. PMID:27414063

  16. Development and validation of an attenuated Mycoplasma hyopneumoniae aerosol vaccine.

    PubMed

    Feng, Zhi-Xin; Wei, Yan-Na; Li, Gui-Lan; Lu, Xiao-Ming; Wan, Xiu-Feng; Pharr, G Todd; Wang, Zhan-Wei; Kong, Meng; Gan, Yuan; Bai, Fang-Fang; Liu, Mao-Jun; Xiong, Qi-Yan; Wu, Xu-Su; Shao, Guo-Qing

    2013-12-27

    Mycoplasma hyopneumoniae (M. hyopneumoniae) causes a chronic respiratory disease with high morbidity and low mortality in swine, and has been presented as a major cause of growth retardation in the swine industry. Aerosol vaccination presents a needle free, high throughput, and efficient platform for vaccine delivery, and has been widely applied in poultry vaccination. However, aerosol vaccines have rarely been used in swine vaccination primarily because the long and curving respiratory track of swine presents a barrier for vaccine particle delivery. To develop an effective M. hyopneumoniae aerosol vaccine, three major barriers need to be overcome: to optimize particle size for aerosol delivery, to maintain the viability of mycoplasma cells in the vaccine, and to optimize the environmental conditions for vaccine delivery. In this study, an aerosol mycoplasma vaccine was successfully developed based on a conventional live attenuated M. hyopneumoniae vaccine. Specifically, the Pari LCD nebulizer was used to produce an aerosol vaccine particle size less than 5 μm; and a buffer with 5% glycerol was developed and optimized to prevent inactivation of M. hyopneumoniae caused by aerosolization and evaporation. Before nebulization, the room temperature and relative humidity were control to 20-25 °C and 70-75%, respectively, which helped maintain the viability of aerosol vaccine. Animal experiments demonstrated that this newly developed aerosol vaccine was effectively delivered to swine low respiratory track, being confirmed by nested-PCR, in situ hybridization and scanning electron microscope. Moreover, M. hyopneumoniae specific sIgA secretion was detected in the nasal swab samples at 14 days post-immunization. To our knowledge, this is the first report on a live M. hyopneumoniae aerosol vaccine. PMID:24035264

  17. Performance of PCR-based and Bioluminescent assays for mycoplasma detection.

    PubMed

    Falagan-Lotsch, Priscila; Lopes, Talíria Silva; Ferreira, Nívea; Balthazar, Nathália; Monteiro, Antônio M; Borojevic, Radovan; Granjeiro, José Mauro

    2015-11-01

    Contaminated eukaryotic cell cultures are frequently responsible for unreliable results. Regulatory entities request that cell cultures must be mycoplasma-free. Mycoplasma contamination remains a significant problem for cell cultures and may have an impact on biological analysis since they affect many cell parameters. The gold standard microbiological assay for mycoplasma detection involves laborious and time-consuming protocols. PCR-based and Bioluminescent assays have been considered for routine cell culture screening in research laboratories since they are fast, easy and sensitive. Thus, the aim of this work is to compare the performance of two popular commercial assays, PCR-based and Bioluminescent assays, by assessing the level of mycoplasma contamination in cell cultures from Rio de Janeiro Cell Bank (RJCB) and also from customers' laboratories. The results obtained by both performed assays were confirmed by scanning electron microscopy. In addition, we evaluated the limit of detection of the PCR kit under our laboratory conditions and the storage effects on mycoplasma detection in frozen cell culture supernatants. The performance of both assays for mycoplasma detection was not significantly different and they showed very good agreement. The Bioluminescent assay for mycoplasma detection was slightly more dependable than PCR-based due to the lack of inconclusive results produced by the first technique, especially considering the ability to detect mycoplasma contamination in frozen cell culture supernatants. However, cell lines should be precultured for four days or more without antibiotics to obtain safe results. On the other hand, a false negative result was obtained by using this biochemical approach. The implementation of fast and reliable mycoplasma testing methods is an important technical and regulatory issue and PCR-based and Bioluminescent assays may be good candidates. However, validation studies are needed. PMID:26296900

  18. MIB–MIP is a mycoplasma system that captures and cleaves immunoglobulin G

    PubMed Central

    Arfi, Yonathan; Minder, Laetitia; Di Primo, Carmelo; Le Roy, Aline; Ebel, Christine; Coquet, Laurent; Claverol, Stephane; Vashee, Sanjay; Jores, Joerg; Blanchard, Alain; Sirand-Pugnet, Pascal

    2016-01-01

    Mycoplasmas are “minimal” bacteria able to infect humans, wildlife, and a large number of economically important livestock species. Mycoplasma infections include a spectrum of clinical manifestations ranging from simple fever to fulminant inflammatory diseases with high mortality rates. These infections are mostly chronic, suggesting that mycoplasmas have developed means to evade the host immune response. Here we present and functionally characterize a two-protein system from Mycoplasma mycoides subspecies capri that is involved in the capture and cleavage of IgG. The first component, Mycoplasma Ig binding protein (MIB), is an 83-kDa protein that is able to tightly bind to the Fv region of a wide range of IgG. The second component, Mycoplasma Ig protease (MIP), is a 97-kDa serine protease that is able to cleave off the VH domain of IgG. We demonstrate that MIB is necessary for the proteolytic activity of MIP. Cleavage of IgG requires a sequential interaction of the different partners of the system: first MIB captures the IgG, and then MIP is recruited to the MIB–IgG complex, enabling protease activity. MIB and MIP are encoded by two genes organized in tandem, with homologs found in the majority of pathogenic mycoplasmas and often in multiple copies. Phylogenetic studies suggest that genes encoding the MIB–MIP system are specific to mycoplasmas and have been disseminated by horizontal gene transfer. These results highlight an original and complex system targeting the host immunoglobulins, playing a potentially key role in the immunity evasion by mycoplasmas. PMID:27114507

  19. MIB-MIP is a mycoplasma system that captures and cleaves immunoglobulin G.

    PubMed

    Arfi, Yonathan; Minder, Laetitia; Di Primo, Carmelo; Le Roy, Aline; Ebel, Christine; Coquet, Laurent; Claverol, Stephane; Vashee, Sanjay; Jores, Joerg; Blanchard, Alain; Sirand-Pugnet, Pascal

    2016-05-10

    Mycoplasmas are "minimal" bacteria able to infect humans, wildlife, and a large number of economically important livestock species. Mycoplasma infections include a spectrum of clinical manifestations ranging from simple fever to fulminant inflammatory diseases with high mortality rates. These infections are mostly chronic, suggesting that mycoplasmas have developed means to evade the host immune response. Here we present and functionally characterize a two-protein system from Mycoplasma mycoides subspecies capri that is involved in the capture and cleavage of IgG. The first component, Mycoplasma Ig binding protein (MIB), is an 83-kDa protein that is able to tightly bind to the Fv region of a wide range of IgG. The second component, Mycoplasma Ig protease (MIP), is a 97-kDa serine protease that is able to cleave off the VH domain of IgG. We demonstrate that MIB is necessary for the proteolytic activity of MIP. Cleavage of IgG requires a sequential interaction of the different partners of the system: first MIB captures the IgG, and then MIP is recruited to the MIB-IgG complex, enabling protease activity. MIB and MIP are encoded by two genes organized in tandem, with homologs found in the majority of pathogenic mycoplasmas and often in multiple copies. Phylogenetic studies suggest that genes encoding the MIB-MIP system are specific to mycoplasmas and have been disseminated by horizontal gene transfer. These results highlight an original and complex system targeting the host immunoglobulins, playing a potentially key role in the immunity evasion by mycoplasmas. PMID:27114507

  20. Dendritic Cells Are the Major Antigen Presenting Cells in Inflammatory Lesions of Murine Mycoplasma Respiratory Disease

    PubMed Central

    Sun, Xiangle; Jones, Harlan P.; Dobbs, Nicole; Bodhankar, Sheetal; Simecka, Jerry W.

    2013-01-01

    Mycoplasmas cause chronic respiratory diseases in animals and humans, and to date, development of vaccines have been problematic. Using a murine model of mycoplasma pneumonia, lymphocyte responses, specifically T cells, were shown to confer protection as well as promote immunopathology in mycoplasma disease. Because T cells play such a critical role, it is important to define the role of antigen presenting cells (APC) as these cells may influence either exacerbation of mycoplasma disease pathogenesis or enhancement of protective immunity. The roles of APC, such as dendritic cells and/or macrophages, and their ability to modulate adaptive immunity in mycoplasma disease are currently unknown. Therefore, the purpose of this study was to identify individual pulmonary APC populations that may contribute to the activation of T cell responses during mycoplasma disease pathogenesis. The present study indeed demonstrates increasing numbers of CD11c− F4/80+ cells, which contain macrophages, and more mature/activated CD11c+ F4/80− cells, containing DC, in the lungs after infection. CD11c− F4/80+ macrophage-enriched cells and CD11c+ F4/80− dendritic cell-enriched populations showed different patterns of cytokine mRNA expression, supporting the idea that these cells have different impacts on immunity in response to infection. In fact, DC containing CD11c+ F4/80− cell populations from the lungs of infected mice were most capable of stimulating mycoplasma-specific CD4+ Th cell responses in vitro. In vivo, these CD11c+F4/80− cells were co-localized with CD4+ Th cells in inflammatory infiltrates in the lungs of mycoplasma-infected mice. Thus, CD11c+F4/80− dendritic cells appear to be the major APC population responsible for pulmonary T cell stimulation in mycoplasma-infected mice, and these dendritic cells likely contribute to responses impacting disease pathogenesis. PMID:23390557

  1. Pilot study to evaluate the role of Mycoplasma species in cat bite abscesses.

    PubMed

    Torres-Henderson, Camille; Hesser, Jeff; Hyatt, Doreene R; Hawley, Jennifer; Brewer, Melissa; Lappin, Michael R

    2014-12-01

    Mycoplasma species are common inhabitants of the feline oral cavity, and so likely contaminate many cat bite abscesses. The objectives of this study were to determine whether Mycoplasma species are common contaminants of cat bite abscesses and whether they are are associated with β-lactam-resistant clinical disease. Twenty-six privately owned cats with clinical evidence of an abscess suspected to be from a cat bite were included in the study. Samples from each cat were evaluated by aerobic and anaerobic culture, as well as Mycoplasma species culture and polymerase chain reaction (PCR). All cats were initially treated with appropriate wound management and were administered an antibiotic of the β-lactam class (amoxicillin, amoxicillin clavulanate or cefovecin sodium). Mycoplasma species DNA was amplified by PCR from 4/26 samples (15.4%); one of these cases was concurrently culture positive. Adequate DNA for sequencing was present for 2/4 positive PCR samples; one was most homologous with Mycoplasma felis, and the other was most homologous with Mycoplasma equigenitalium and Mycoplasma elephantis. Of the 26 cats, 25 responded to the initial treatment by day 7. The cat that failed initial treatment was positive for M equigenitalium or M elephantis DNA on days 0 and 12, and ultimately responded to administration of enrofloxacin and clindamycin. The results suggest that while Mycoplasma species can contaminate cat bite abscesses, routine wound management and β-lactam antibiotic therapy is adequate for treatment in most cases of abscess. However, as Mycoplasma species infections do not respond to β-lactam class antibiotic therapy, these organisms should be on the differential list for cats with abscesses that fail treatment with this antibiotic class. PMID:24643287

  2. Mycoplasma felis pleuritis in two show-jumper horses.

    PubMed

    Hoffman, A M; Baird, J D; Kloeze, H J; Rosendal, S; Bell, M

    1992-04-01

    Mycoplasma felis was identified as the cause of acute pleuritis in 2 show-jumping horses. The pleural exudate was proteinaceous, contained large numbers of neutrophils, and had a markedly increased lactate concentration. M. felis was isolated in pure culture from pleural fluid. Rising serum antibody titers to M. felis as well as a precipitous decline in titers to equine influenza virus were demonstrated in both horses. Pleural effusion in both horses and a pneumothorax detected in one of the horses resolved following a single drainage of pleural fluid and intravenous fluid, antibiotic, and analgesic therapy. PMID:1623728

  3. Eggshell apex abnormalities associated with Mycoplasma synoviae infection in layers.

    PubMed

    Jeon, Eun-Ok; Kim, Jong-Nyeo; Lee, Hae-Rim; Koo, Bon-Sang; Min, Kyeong-Cheol; Han, Moo-Sung; Lee, Seung-Baek; Bae, Yeon-Ji; Mo, Jong-Suk; Cho, Sun-Hyung; Lee, Chang-Hee; Mo, In-Pil

    2014-12-01

    Eggs exhibiting eggshell apex abnormalities (EAA) were evaluated for changes in shell characteristics such as strength, thickness, and ultrastructure. Mycoplasma synoviae (MS) infection was confirmed by serological assay along with isolation of MS from the trachea and oviduct. Changes in eggshell quality were shown to be statistically significant (p < 0.01). We also identified ultrastructural changes in the mammillary knob layer by Scanning Electron Microscopy. While eggs may seem to be structurally sound, ultrastructural evaluation showed that affected eggs do not regain their former quality. In our knowledge, this is the first report describing the occurrence of EAA in Korea. PMID:24962418

  4. Mechanisms involved in quinolone resistance in Mycoplasma mycoides subsp. capri.

    PubMed

    Antunes, Nuno T; Assunção, Patrícia; Poveda, José B; Tavío, María M

    2015-06-01

    Mycoplasma mycoides subsp. capri is a causative agent of contagious agalactia in goats. In this study, M. mycoides subsp. capri mutants were selected for resistance to fluoroquinolones (norfloxacin, enrofloxacin and ciprofloxacin) by serial passes in broth with increasing concentrations of antibiotic. Mutations conferring cross-resistance to the three fluoroquinolones were found in the quinolone resistance determining regions of the four genes encoding DNA gyrase and topoisomerase IV. Different mutations in the DNA gyrase GyrA subunit suggest a different mechanism of inhibition between norfloxacin and the other tested fluoroquinolones. The presence of an adenosine triphosphate-dependent efflux system was suggested through the use of the inhibitor orthovanadate. PMID:25951987

  5. Mycoplasma gallisepticum infection in chukar partridges, pheasants, and peafowl.

    PubMed

    Cookson, K C; Shivaprasad, H L

    1994-01-01

    Mycoplasma gallisepticum infection was diagnosed in a group of chukar partridges, pheasants, and peafowl based on serology and isolation techniques. The farm also had quail, chickens, and ducks. Clinical signs in growing birds consisted of foamy eyes, swollen infraorbital sinuses, respiratory distress, and death. Breeding birds experienced a severe drop in egg production. Histologically, the growing birds exhibited lymphoplasmacytic inflammation of the conjunctiva, sinus, and trachea. The most likely source of infection was either chickens, which had been introduced before the onset of clinical signs, or the chukar partridge breeders, which had been obtained at various hunting field trials. PMID:7702531

  6. Examining spring wet slab and glide avalanche occurrence along the Going-to-the-Sun Road corridor, Glacier National Park, Montana, USA

    USGS Publications Warehouse

    Peitzsch, Erich H.; Jordy Hendrikx; Fagre, Daniel B.; Blase Reardon

    2012-01-01

    The results suggest that the role of air temperature and snowpack settlement appear to be the most important variables in wet slab and glide avalanche occurrence. When applied to the 2011 season, the results of the CART model are encouraging and they enhance our understanding of some of the required meteorological and snowpack conditions for wet slab and glide avalanche occurrence.

  7. Mycoplasma sturni from blue jays and northern mockingbirds with conjunctivitis in Florida.

    PubMed

    Ley, D H; Geary, S J; Berkhoff, J E; McLaren, J M; Levisohn, S

    1998-04-01

    Northern mockingbirds (Mimus polyglottos) and blue jays (Cyanocitta cristata) in a Florida (USA) wildlife care facility developed clinical signs and gross lesions suggestive of the ongoing outbreak of Mycoplasma gallisepticum (MG) conjunctivitis in house finches (Carpodacus mexicanus) and American goldfinches (Carduelis tristis). Mycoplasmal organisms were cultured from conjunctival/corneal swabs of birds with sinusitis, conjunctivitis, and/or epiphora. All of the isolates tested were identified as Mycoplasma sturni by indirect immunofluorescence. Mycoplasma sturni as well as MG should be considered in the differential diagnosis of songbirds with conjunctivitis. PMID:9577796

  8. Acute respiratory distress syndrome caused by Mycoplasma pneumoniae without elevated pulmonary vascular permeability: a case report

    PubMed Central

    Takahashi, Naoki; Oi, Rie; Ota, Muneyuki; Toriumi, Shinichi; Ogushi, Fumitaka

    2016-01-01

    Sporadic patients with acute respiratory distress syndrome (ARDS) caused by Mycoplasma pneumoniae have been reported. However, knowledge about the pathophysiology and pharmacological treatment of this condition is insufficient. Moreover, the pulmonary vascular permeability in ARDS related to M. pneumoniae infection has not been reported. We report a case of ARDS caused by Mycoplasma pneumoniae without elevated pulmonary vascular permeability, which was successfully treated using low-dose short-term hydrocortisone, suggesting that pulmonary infiltration in ARDS caused by Mycoplasma pneumoniae does not match the criteria of permeability edema observed in typical ARDS. PMID:27162691

  9. Acute respiratory distress syndrome caused by Mycoplasma pneumoniae without elevated pulmonary vascular permeability: a case report.

    PubMed

    Takahashi, Naoki; Shinohara, Tsutomu; Oi, Rie; Ota, Muneyuki; Toriumi, Shinichi; Ogushi, Fumitaka

    2016-05-01

    Sporadic patients with acute respiratory distress syndrome (ARDS) caused by Mycoplasma pneumoniae have been reported. However, knowledge about the pathophysiology and pharmacological treatment of this condition is insufficient. Moreover, the pulmonary vascular permeability in ARDS related to M. pneumoniae infection has not been reported. We report a case of ARDS caused by Mycoplasma pneumoniae without elevated pulmonary vascular permeability, which was successfully treated using low-dose short-term hydrocortisone, suggesting that pulmonary infiltration in ARDS caused by Mycoplasma pneumoniae does not match the criteria of permeability edema observed in typical ARDS. PMID:27162691

  10. Mycoplasmas and their host: emerging and re-emerging minimal pathogens.

    PubMed

    Citti, Christine; Blanchard, Alain

    2013-04-01

    Commonly known as mycoplasmas, bacteria of the class Mollicutes include the smallest and simplest life forms capable of self replication outside of a host. Yet, this minimalism hides major human and animal pathogens whose prevalence and occurrence have long been underestimated. Owing to advances in sequencing methods, large data sets have become available for a number of mycoplasma species and strains, providing new diagnostic approaches, typing strategies, and means for comprehensive studies. A broader picture is thus emerging in which mycoplasmas are successful pathogens having evolved a number of mechanisms and strategies for surviving hostile environments and adapting to new niches or hosts. PMID:23419218

  11. The percentage of CD133+ cells in human colorectal cancer cell lines is influenced by Mycoplasma hyorhinis infection

    PubMed Central

    2010-01-01

    Background Mollicutes contamination is recognized to be a critical issue for the cultivation of continuous cell lines. In this work we characterized the effect of Mycoplasma hyorhinis contamination on CD133 expression in human colon cancer cell lines. Methods MycoAlert® and mycoplasma agar culture were used to detect mycoplasma contamination on GEO, SW480 and HT-29 cell lines. Restriction fragment length polymorphism assay was used to determine mycoplasma species. All cellular models were decontaminated by the use of a specific antibiotic panel (Enrofloxacin, Ciprofloxacin, BM Cyclin 1 and 2, Mycoplasma Removal Agent and MycoZap®). The percentage of CD133 positive cells was analyzed by flow cytometry on GEO, SW480 and HT-29 cell lines, before and after Mycoplasma hyorhinis eradication. Results Mycoplasma hyorhinis infected colon cancer cell lines showed an increased percentage of CD133+ cells as compared to the same cell lines rendered mycoplasma-free by effective exposure to antibiotic treatment. The percentage of CD133 positive cells increased again when mycoplasma negative cells were re-infected by Mycoplasma hyorhinis. Conclusions Mycoplasma hyorhinis infection has an important role on the quality of cultured human colon cancer cell lines giving a false positive increase of cancer stem cells fraction characterized by CD133 expression. Possible explanations are (i) the direct involvement of Mycoplasma on CD133 expression or (ii) the selective pressure on a subpopulation of cells characterized by constitutive CD133 expression. In keeping with United Kingdom Coordinating Committee on Cancer Research (UKCCCR) guidelines, the present data indicate the mandatory prerequisite, for investigators involved in human colon cancer research area, of employing mycoplasma-free cell lines in order to avoid the production of non-reproducible or even false data. PMID:20353562

  12. Effect of Mulligan’s mobilization with movement technique on gait function in stroke patients

    PubMed Central

    Kim, Sang-Lim; Lee, Byoung-Hee

    2016-01-01

    [Purpose] We examined the effectiveness of Mulligan’s mobilization with movement (MWM) technique on spatiotemporal variables of gait in individuals who had a stroke. [Subjects and Methods] Twenty-four subjects were randomly divided into 2 groups: Mulligan’s mobilization with movement group (n=12) and “weight-bearing with placebo” mobilization with movement group (n=12). The subjects in the mobilization with movement group performed 5 sets of 10 glides a day, 5 times a week for 4 weeks. The mobilization with movement technique comprised grade III movements that involved gliding and resting. The control group subjects performed lunges in the same conditions as those of the experimental group. Gait function was measured in terms of spatiotemporal parameters to determine the effect of mobilization with movement. [Results] The mobilization with movement group showed significant improvements in velocity, cadence, stride length, single-support time, and step length of the affected side, and step length and stride length of the non-affected side. Overall, the mobilization with movement group showed significantly greater improvements than the control group in terms of velocity, cadence, and single-support time of the affected side. [Conclusion] Mobilization with movement can be used to improve the gait function of patients recovering from stroke.

  13. Clinical Features of Severe or Fatal Mycoplasma pneumoniae Pneumonia

    PubMed Central

    Izumikawa, Koichi

    2016-01-01

    Mycoplasma pneumoniae is one of the most common causes of community-acquired pneumonia in children and young adults. The incidence of fulminant M. pneumoniae pneumonia (MPP) is relatively rare despite the high prevalence of M. pneumoniae infection. This literature review highlights the clinical features of fulminant MPP by examining the most recent data in epidemiology, clinical presentation, pathogenesis, and treatment. Fulminant MPP accounts for 0.5–2% of all MPP cases and primarily affects young adults with no underlying disease. Key clinical findings include a cough, fever, and dyspnea along with diffuse abnormal findings in radiological examinations. Levels of inflammatory markers such as white blood cells and C-reactive protein are elevated, as well as levels of lactate dehydrogenase, IL-18, aspartate transaminase, and alanine transaminase. The exact pathogenesis of fulminant MPP remains unclear, but theories include a delayed hypersensitivity reaction to M. pneumoniae and the contribution of delayed antibiotic administration to disease progression. Treatment options involve pairing the appropriate anti-mycoplasma agent with a corticosteroid that will downregulate the hypersensitivity response, and mortality rates are quite low in this treatment group. Further research is necessary to determine the exact pathogenesis of severe and fulminant types of MPP. PMID:27313568

  14. Genomic Investigations Unmask Mycoplasma amphoriforme, a New Respiratory Pathogen

    PubMed Central

    Gillespie, Stephen H.; Ling, Clare L.; Oravcova, Katarina; Pinheiro, Miguel; Wells, Louise; Bryant, Josephine M.; McHugh, Timothy D.; Bébéar, Cecile; Webster, David; Harris, Simon R.; Seth-Smith, Helena M. B.; Thomson, Nicholas R.

    2015-01-01

    Background. Mycoplasma amphoriforme has been associated with infection in patients with primary antibody deficiency (PAD). Little is known about the natural history of infection with this organism and its ability to be transmitted in the community. Methods. The bacterial load was estimated in sequential sputum samples from 9 patients by quantitative polymerase chain reaction. The genomes of all available isolates, originating from patients in the United Kingdom, France, and Tunisia, were sequenced along with the type strain. Genomic data were assembled and annotated, and a high-resolution phylogenetic tree was constructed. Results. By using high-resolution whole-genome sequencing (WGS) data, we show that patients can be chronically infected with M. amphoriforme manifesting as a relapsing-remitting bacterial load, interspersed by periods when the organism is undetectable. Importantly, we demonstrate transmission of strains within a clinical environment. Antibiotic resistance mutations accumulate in isolates taken from patients who received multiple courses of antibiotics. Conclusions. Mycoplasma amphoriforme isolates form a closely related species responsible for a chronic relapsing and remitting infection in PAD patients in the United Kingdom and from immunocompetent patients in other countries. We provide strong evidence of transmission between patients attending the same clinic, suggesting that screening and isolation may be necessary for susceptible patients. This work demonstrates the critical role that WGS can play in rapidly unraveling the biology of a novel pathogen. PMID:25344534

  15. Detection of antibodies to Mycoplasma felis in horses.

    PubMed

    Rosendal, S; Blackwell, T E; Lumsden, J H; Physick-Sheard, P W; Viel, L; Watson, S; Woods, P

    1986-02-01

    Mycoplasma felis has been isolated from horses with pleuritis, and limited research indicates that mycoplasma pleuritis can be reproduced in horses. The serodiagnostic potential of the indirect hemagglutination and the metabolism-inhibition tests was evaluated by testing 177 horses for antibodies to M felis. Seven horses with M felis pleuritis developed antibodies, and 6 horses with sterile or bacterial pleuritis had high titers suggesting a previous M felis infection. Six horses with pleuritis (one sterile and five bacterial) had low or no titers to M felis. Only one of 30 horses with conditions other than respiratory diseases seroconverted during hospitalization and the remaining horses had low titers. Seventy-eight foals, 4 to 6 months old, from one farm did not have titers, whereas 7 out of 50 yearlings from the same farm had high titers in the indirect hemagglutination test and titers in the metabolism-inhibition test. It appears that both tests are suitable for serodiagnosis of M felis infection in horses. PMID:3949603

  16. Mycoplasma hyopneumoniae Transcription Unit Organization: Genome Survey and Prediction

    PubMed Central

    Siqueira, Franciele Maboni; Schrank, Augusto; Schrank, Irene Silveira

    2011-01-01

    Mycoplasma hyopneumoniae is associated with swine respiratory diseases. Although gene organization and regulation are well known in many prokaryotic organisms, knowledge on mycoplasma is limited. This study performed a comparative analysis of three strains of M. hyopneumoniae (7448, J and 232), with a focus on genome organization and gene comparison for open read frame (ORF) cluster (OC) identification. An in silico analysis of gene organization demonstrated 117 OCs and 34 single ORFs in M. hyopneumoniae 7448 and J, while 116 OCs and 36 single ORFs were identified in M. hyopneumoniae 232. Genomic comparison revealed high synteny and conservation of gene order between the OCs defined for 7448 and J strains as well as for 7448 and 232 strains. Twenty-one OCs were chosen and experimentally confirmed by reverse transcription–PCR from M. hyopneumoniae 7448 genome, validating our prediction. A subset of the ORFs within an OC could be independently transcribed due to the presence of internal promoters. Our results suggest that transcription occurs in ‘run-on’ from an upstream promoter in M. hyopneumoniae, thus forming large ORF clusters (from 2 to 29 ORFs in the same orientation) and indicating a complex transcriptional organization. PMID:22086999

  17. Unveiling Mycoplasma hyopneumoniae Promoters: Sequence Definition and Genomic Distribution

    PubMed Central

    Weber, Shana de Souto; Sant'Anna, Fernando Hayashi; Schrank, Irene Silveira

    2012-01-01

    Several Mycoplasma species have had their genome completely sequenced, including four strains of the swine pathogen Mycoplasma hyopneumoniae. Nevertheless, little is known about the nucleotide sequences that control transcriptional initiation in these microorganisms. Therefore, with the objective of investigating the promoter sequences of M. hyopneumoniae, 23 transcriptional start sites (TSSs) of distinct genes were mapped. A pattern that resembles the σ70 promoter −10 element was found upstream of the TSSs. However, no −35 element was distinguished. Instead, an AT-rich periodic signal was identified. About half of the experimentally defined promoters contained the motif 5′-TRTGn-3′, which was identical to the −16 element usually found in Gram-positive bacteria. The defined promoters were utilized to build position-specific scoring matrices in order to scan putative promoters upstream of all coding sequences (CDSs) in the M. hyopneumoniae genome. Two hundred and one signals were found associated with 169 CDSs. Most of these sequences were located within 100 nucleotides of the start codons. This study has shown that the number of promoter-like sequences in the M. hyopneumoniae genome is more frequent than expected by chance, indicating that most of the sequences detected are probably biologically functional. PMID:22334569

  18. Prevalence of Mycoplasma ovipneumoniae in desert bighorn sheep in Arizona

    USGS Publications Warehouse

    Justice-Allen, Anne E.; Luedtke, Clint J.; Overstreet, Matthew; Cain, James W.; Stephenson, Thomas R.

    2011-01-01

    To assess the potential for an epizootic of pneumonia to result from either natural immigration or translocation, we compared the seroprevalence to Mycoplasma ovipneumoniae in several populations of desert bighorn sheep in Arizona. We collected blood samples and nasal or oropharyngeal swabs from 124 desert bighorn sheep (Ovis canadensis nelsoni) from 6 populations in Arizona in 2009 and 2010. M. ovipneumoniae organisms were detected by PCR in 22%, whereas antibodies to M. ovipneumoniae were detected in 47% of tested bighorn sheep. Mycoplasma antibodies were not found in 2 of 6 populations, indicating some bighorn sheep populations in Arizona are naïve to this bacterium. In contrast, others had seroprevalence rates up to 80%. We were able to compare seroprevalence rates and titers over time in 9 individuals (7 individuals included in the 124 bighorn sheep sampled in 2009 and 2010, and 2 individuals originally captured in 2006). Antibody titers persisted for 12 months in individuals from the Kofa National Wildlife Refuge (n = 7) while antibody titers appeared to decline in the Kanab Creek population (n = 2). M. ovipneumoniae is present or has been present in several, but not all, populations of bighorn sheep in Arizona. The results demonstrate the importance of routine health testing for future translocation efforts to reduce disease risk for naive populations.

  19. Severe Mycoplasma bovis outbreak in an Austrian dairy herd.

    PubMed

    Pothmann, Harald; Spergser, Joachim; Elmer, Josef; Prunner, Isabella; Iwersen, Michael; Klein-Jöbstl, Daniela; Drillich, Marc

    2015-11-01

    A conventional dairy farm, housing 19 Austrian Simmental cows, experienced a spontaneous outbreak of a Mycoplasma bovis infection, showing severe clinical signs of respiratory tract disease, clinical mastitis, and tremendous drop in milk production. Despite intensive therapy, 5 cows died within 2 weeks or were euthanized. From the remaining cows, bacteriological culture and polymerase chain reaction revealed M. bovis in 10 of 14 milk samples. Mycoplasma bovis was found in 1 of 5 randomly collected nasal swabs. Autopsy of 1 cow revealed infection of the lungs and the udder with M. bovis. The 13 M. bovis isolates from milk samples, nasal swabs, lungs, and udder were genotyped by multilocus variable number of tandem-repeat analysis, and indicated that described infections were caused by a single M. bovis strain. The virulent M. bovis strain resulted in dramatic economic loss to the farmer. To control the disease, culling of all animals, including heifers and calves, was recommended, and strict hygienic measures were implemented before introducing new animals to the farm. PMID:26450838

  20. Resistance to Antimicrobial Peptides and Stress Response in Mycoplasma pulmonis

    PubMed Central

    Fehri, Lina Fassi; Sirand-Pugnet, Pascal; Gourgues, Géraldine; Jan, Gwenaël; Wróblewski, Henri; Blanchard, Alain

    2005-01-01

    Antimicrobial peptides are widely distributed in nature, and in vertebrates, they play a key function in the innate immune defense system. It is generally agreed that these molecules may provide new antibiotics with therapeutic value. However, there are still many unsolved questions regarding the mechanisms underlying their antimicrobial activity as well as the mechanisms of resistance evolved by microorganisms against these molecules. The second point was addressed in this study. After determining the activity of 10 antimicrobial peptides against Mycoplasma pulmonis, a murine respiratory pathogen, the development of resistance was investigated. Following in vitro selection using subinhibitory concentrations of peptides, clones of this bacterium showing increased resistance to melittin or gramicidin D were obtained. For some of the clones, a cross-resistance was observed between these two peptides, in spite of their deep structural differences, and also with tetracycline. A proteomic analysis suggested that the stress response in these clones was constitutively activated, and this was confirmed by finding mutations in the hrcA gene; in mycoplasmas, bacteria which lack alternative sigma factors, the HrcA protein is supposed to play a key role as a negative regulator of heat shock proteins. By complementation of the hrcA mutants with the wild-type gene, the initial MICs of melittin and gramicidin D decreased to values close to the initial ones. This indicates that the resistance of M. pulmonis to these two antimicrobial peptides could result from a stress response involving HrcA-regulated genes. PMID:16189093

  1. Isothermal Detection of Mycoplasma pneumoniae Directly from Respiratory Clinical Specimens

    PubMed Central

    Petrone, Brianna L.; Wolff, Bernard J.; DeLaney, Alexandra A.; Diaz, Maureen H.

    2015-01-01

    Mycoplasma pneumoniae is a leading cause of community-acquired pneumonia (CAP) across patient populations of all ages. We have developed a loop-mediated isothermal amplification (LAMP) assay that enables rapid, low-cost detection of M. pneumoniae from nucleic acid extracts and directly from various respiratory specimen types. The assay implements calcein to facilitate simple visual readout of positive results in approximately 1 h, making it ideal for use in primary care facilities and resource-poor settings. The analytical sensitivity of the assay was determined to be 100 fg by testing serial dilutions of target DNA ranging from 1 ng to 1 fg per reaction, and no cross-reactivity was observed against 17 other Mycoplasma species, 27 common respiratory agents, or human DNA. We demonstrated the utility of this assay by testing nucleic acid extracts (n = 252) and unextracted respiratory specimens (n = 72) collected during M. pneumoniae outbreaks and sporadic cases occurring in the United States from February 2010 to January 2014. The sensitivity of the LAMP assay was 88.5% tested on extracted nucleic acid and 82.1% evaluated on unextracted clinical specimens compared to a validated real-time PCR test. Further optimization and improvements to this method may lead to the availability of a rapid, cost-efficient laboratory test for M. pneumoniae detection that is more widely available to primary care facilities, ultimately facilitating prompt detection and appropriate responses to potential M. pneumoniae outbreaks and clusters within the community. PMID:26179304

  2. First isolation of Mycoplasma iowae in grey partridge flocks.

    PubMed

    Catania, S; Gobbo, F; Rodio, S; Qualtieri, K; Santone, C; Nicholas, R A J

    2014-06-01

    Mycoplasma iowae, an occasional pathogen of turkeys, was isolated for the first time from captive grey partridges (Perdix perdix). Clinical signs including respiratory and intestinal disorder were seen in birds of all ages but mainly in those kept housed during rearing. Mortality rates averaged over 20% during the year. Treatment with antibiotics and antiparasitic drugs produced only a transient improvement in condition. The gross pathology findings included poor body growth, lack of development of the breast muscles, abnormalities in the keel development, and bone fragility. Some birds showed infraorbital sinusitis with serous or fibrinous exudates and catarrhal tracheitis, while others presented serofibrinous airsacculitis and splenomegaly. Laboratory investigations revealed pure cultures of M. iowae in the gut as well as sinus and air sacs. While other organisms such as coccidia, Trichomonas, Escherichia coli, Clostridium perfringens, and Aspergillus spp. were detected, the similarity of the disease with that seen in turkeys infected with M. iowae strongly suggests that this mycoplasma may be the primary pathogen here. The presence of M. iowae in game birds commonly released into the wild could have serious implications particularly in areas where industrial poultry farms are concentrated. PMID:25055642

  3. Gliding Box method applied to trace element distribution of a geochemical data set

    NASA Astrophysics Data System (ADS)

    Paz González, Antonio; Vidal Vázquez, Eva; Rosario García Moreno, M.; Paz Ferreiro, Jorge; Saa Requejo, Antonio; María Tarquis, Ana

    2010-05-01

    The application of fractal theory to process geochemical prospecting data can provide useful information for evaluating mineralization potential. A geochemical survey was carried out in the west area of Coruña province (NW Spain). Major elements and trace elements were determined by standard analytical techniques. It is well known that there are specific elements or arrays of elements, which are associated with specific types of mineralization. Arsenic has been used to evaluate the metallogenetic importance of the studied zone. Moreover, as can be considered as a pathfinder of Au, as these two elements are genetically associated. The main objective of this study was to use multifractal analysis to characterize the distribution of three trace elements, namely Au, As, and Sb. Concerning the local geology, the study area comprises predominantly acid rocks, mainly alkaline and calcalkaline granites, gneiss and migmatites. The most significant structural feature of this zone is the presence of a mylonitic band, with an approximate NE-SW orientation. The data set used in this study comprises 323 samples collected, with standard geochemical criteria, preferentially in the B horizon of the soil. Occasionally where this horizon was not present, samples were collected from the C horizon. Samples were taken in a rectilinear grid. The sampling lines were perpendicular to the NE-SW tectonic structures. Frequency distributions of the studied elements departed from normal. Coefficients of variation ranked as follows: Sb < As < Au. Significant correlation coefficients between Au, Sb, and As were found, even if these were low. The so-called ‘gliding box' algorithm (GB) proposed originally for lacunarity analysis has been extended to multifractal modelling and provides an alternative to the ‘box-counting' method for implementing multifractal analysis. The partitioning method applied in GB algorithm constructs samples by gliding a box of certain size (a) over the grid map in all

  4. The effect of vegetation cover on the formation of glide-snow avalanches

    NASA Astrophysics Data System (ADS)

    Feistl, Thomas; Bebi, Peter; Bartelt, Perry

    2014-05-01

    Glide snow avalanches release on steep, smooth slopes and can be prevented either by protection forests or by artificial defense structures. To minimize the risk for people and infrastructure, guidelines have been formulated concerning structure, height and distance between avalanche prevention bridges. These guidelines assure the major functions of the defense structures: first to prevent the release of avalanches and second to withstand the static and dynamic forces of the moving snow cover. The major functions of protection forests are generally similar and therefore guidelines on the maximum tolerable size of forest gaps exist in Switzerland. These guidelines are based on a static relationship between the pressure of the snow cover and the resistance of the defense structure and on empirical observations (forest). Whereas ground friction is only qualitatively taken into account, we assume it to play a crucial role in glide snow avalanche formation. To prove this assumption we collected data on the predominant vegetation cover of 67 release areas in the region of Davos, Switzerland. Our observations reveal a strong relationship between vegetation cover type, slope angle and slab length. We were able to quantify the Coulomb friction parameter μ by applying a physical model that accounts for the dynamic forces of the moving snow on the stauchwall, the fixed snow cover below the release area. The stauchwall resists the dynamic forces of the snow cover, until a critical strain rate is reached and then fails in brittle compression. This failure strongly depends on the friction between snow cover and soil. A typical value of μ for grassy slopes is 0.2. Snow characteristics like density are implemented in the model as constants. We compared the model results with the guidelines for defense structures and forest gap sizes and found accordance for certain friction parameter values. Forest gaps of 40 meter length and a 35° slope angle require friction values of 0

  5. Differential Recognition of Pitch Patterns in Discrete and Gliding Stimuli in Congenital Amusia: Evidence from Mandarin Speakers

    ERIC Educational Resources Information Center

    Liu, Fang; Xu, Yi; Patel, Aniruddh D.; Francart, Tom; Jiang, Cunmei

    2012-01-01

    This study examined whether "melodic contour deafness" (insensitivity to the direction of pitch movement) in congenital amusia is associated with specific types of pitch patterns (discrete versus gliding pitches) or stimulus types (speech syllables versus complex tones). Thresholds for identification of pitch direction were obtained using discrete…

  6. Flavobacterium columnare type IX secretion system mutations result in defects in gliding motility and loss of virulence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The gliding bacterium Flavobacterium columnare causes columnaris disease in wild and aquaculture-reared freshwater fish. The mechanisms responsible for columnaris disease are not known. The related bacterium Flavobacterium johnsoniae uses a type IX secretion system (T9SS) to secrete enzymes, adhesin...

  7. Spray application of live attenuated F Strain-derived Mycoplasma gallisepticum vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Live attenuated vaccines (LAVs) are commonly utilized to protect commercial table egg producers from economic losses associated with challenges by the respiratory pathogen Mycoplasma gallisepticum (MG). Currently there are four MG LAVs commercially available within the United States. Consistent am...

  8. A comparison of molecular assays for Mycoplasma pneumoniae in pediatric patients.

    PubMed

    Chou, Raymond C; Zheng, Xiaotian

    2016-05-01

    Three commercial molecular assays for detecting Mycoplasma pneumoniae were evaluated for their relative performances and hands-on time. They performed comparably well in clinical sensitivity and specificity. PMID:26830272

  9. A disseminated Mycoplasma hominis infection in a patient with an underlying defect in humoral immunity.

    PubMed

    Nulens, Eric; Van Praet, Jens; Selleslag, Dominik; Van Landschoot, Thomas; Dekeyzer, Dieter; Descheemaecker, Patrick; Reynders, Marijke

    2016-06-01

    Non-urogenital Mycoplasma hominis infections are rare, but may cause life-threatening complications. We describe a case of disseminated M. hominis infection with extensive abscess formation in an immunocompromised patient with iatrogenic hypogammaglobulinemia under rituximab treatment. PMID:26546371

  10. DEMONSTRATION OF MULTIPLE ANTIGENIC DETERMINANTS ON 'MYCOPLASMA PNEUMONIAE' ATTACHMENT PROTEIN BY MONOCLONAL ANTIBODIES

    EPA Science Inventory

    Distinct multiple antigenic determinants of the attachment protein of Mycoplasma pneumoniae have been identified by limited proteolytic cleavage using specific monoclonal antibodies. Western blots prepared from the gels containing the cleaved fragments were probed with antiserum ...

  11. Metabolism of 14C-urea by T-strain mycoplasma.

    PubMed

    Ford, D K; McCandlish, K L; Gronlund, A F

    1970-05-01

    When (14)C-labeled urea was metabolized by T-strain mycoplasma, 94 to 95% of the radioactivity was recovered as (14)CO(2), and significant radioactivity was not incorporated into cellular material. PMID:5419267

  12. Mobile Learning Using Mobile Phones

    ERIC Educational Resources Information Center

    Vicente, Paula

    2013-01-01

    The participation in mobile learning programs is conditioned by having/using mobile communication technology. Those who do not have or use such technology cannot participate in mobile learning programs. This study evaluates who are the most likely participants of mobile learning programs by examining the demographic profile and mobile phone usage…

  13. Crawling and Gliding: A Computational Model for Shape-Driven Cell Migration

    PubMed Central

    Niculescu, Ioana; Textor, Johannes; de Boer, Rob J.

    2015-01-01

    Cell migration is a complex process involving many intracellular and extracellular factors, with different cell types adopting sometimes strikingly different morphologies. Modeling realistically behaving cells in tissues is computationally challenging because it implies dealing with multiple levels of complexity. We extend the Cellular Potts Model with an actin-inspired feedback mechanism that allows small stochastic cell rufflings to expand to cell protrusions. This simple phenomenological model produces realistically crawling and deforming amoeboid cells, and gliding half-moon shaped keratocyte-like cells. Both cell types can migrate randomly or follow directional cues. They can squeeze in between other cells in densely populated environments or migrate collectively. The model is computationally light, which allows the study of large, dense and heterogeneous tissues containing cells with realistic shapes and migratory properties. PMID:26488304

  14. Glide-plane symmetry and superconducting gap structure of iron-based superconductors.

    PubMed

    Wang, Y; Berlijn, T; Hirschfeld, P J; Scalapino, D J; Maier, T A

    2015-03-13

    We consider the effect of glide-plane symmetry of the Fe-pnictogen/chalcogen layer in Fe-based superconductors on pairing in spin fluctuation models. Recent theories have proposed that so-called η-pairing states with nonzero total momentum can be realized and possess exotic properties such as odd parity spin singlet symmetry and time-reversal symmetry breaking. Here we show that η pairing is inevitable when there is orbital weight at the Fermi level from orbitals with even and odd mirror reflection symmetry in z; however, by explicit calculation, we conclude that the gap function that appears in observable quantities is identical to that found in earlier, 1 Fe per unit cell pseudocrystal momentum calculations. PMID:25815960

  15. Kinetic Monte Carlo and density functional study of hydrogen enhanced dislocation glide in silicon

    NASA Astrophysics Data System (ADS)

    Scarle, S.; Ewels, C. P.

    2006-05-01

    We investigate Hydrogen Enhanced Dislocation Glide [HEDG], using n-fold way Kinetic Monte Carlo simulations of the interaction between hydrogen and 90° partial dislocations in silicon, and a range of new density functional calculations. We examine two different hydrogen arrival species, as well as hydrogen recombination at the dislocation. The Monte Carlo simulations use a line-wise description of the dislocation line parameterized using density functional calculations of migration and formation energies of various dislocation line defects and their complexes with hydrogen. From this we suggest that the rate of H2 expulsion from the dislocation core increases as we approach HEDG, but that if the concentration of the hydrogen species goes beyond that required for HEDG it then slows dislocation motion by choking the line with defects comprised of two hydrogen atoms in a reconstruction bond. A `dislocation engine' model is proposed whereby hydrogen enters the dislocation line, catalyses motion, and is expelled along the core as H2.

  16. Automated CFD Database Generation for a 2nd Generation Glide-Back-Booster

    NASA Technical Reports Server (NTRS)

    Chaderjian, Neal M.; Rogers, Stuart E.; Aftosmis, Michael J.; Pandya, Shishir A.; Ahmad, Jasim U.; Tejmil, Edward

    2003-01-01

    A new software tool, AeroDB, is used to compute thousands of Euler and Navier-Stokes solutions for a 2nd generation glide-back booster in one week. The solution process exploits a common job-submission grid environment using 13 computers located at 4 different geographical sites. Process automation and web-based access to the database greatly reduces the user workload, removing much of the tedium and tendency for user input errors. The database consists of forces, moments, and solution files obtained by varying the Mach number, angle of attack, and sideslip angle. The forces and moments compare well with experimental data. Stability derivatives are also computed using a monotone cubic spline procedure. Flow visualization and three-dimensional surface plots are used to interpret and characterize the nature of computed flow fields.

  17. Crawling and Gliding: A Computational Model for Shape-Driven Cell Migration.

    PubMed

    Niculescu, Ioana; Textor, Johannes; de Boer, Rob J

    2015-10-01

    Cell migration is a complex process involving many intracellular and extracellular factors, with different cell types adopting sometimes strikingly different morphologies. Modeling realistically behaving cells in tissues is computationally challenging because it implies dealing with multiple levels of complexity. We extend the Cellular Potts Model with an actin-inspired feedback mechanism that allows small stochastic cell rufflings to expand to cell protrusions. This simple phenomenological model produces realistically crawling and deforming amoeboid cells, and gliding half-moon shaped keratocyte-like cells. Both cell types can migrate randomly or follow directional cues. They can squeeze in between other cells in densely populated environments or migrate collectively. The model is computationally light, which allows the study of large, dense and heterogeneous tissues containing cells with realistic shapes and migratory properties. PMID:26488304

  18. Glide-plane symmetry and superconducting gap structure of iron-based superconductors

    SciTech Connect

    Wang, Yan; Berlijn, Tom; Hirschfeld, Peter J.; Scalapino, Douglas J.; Maier, Thomas A.

    2015-03-10

    We consider the effect of glide-plane symmetry of the Fe-pnictogen/chalcogen layer in Fe-based superconductors on pairing in spin fluctuation models. Recent theories propose that so-called η-pairing states with nonzero total momentum can be realized and possess such exotic properties as odd parity spin singlet symmetry and time-reversal symmetry breaking. Here we show that when there is orbital weight at the Fermi level from orbitals with even and odd mirror reflection symmetry in z, η pairing is inevitable; however, we conclude from explicit calculation that the gap function appearing in observable quantities is identical to that found in earlier pseudocrystal momentum calculations with 1 Fe per unit cell.

  19. Evidence for the transport of impurity hydrogen with gliding dislocations in aluminum

    SciTech Connect

    Itoh, Goroh; Kanno, Motohiro; Koyama, Katsumi

    1996-09-15

    Environmental embrittlement in most metallic materials is known to be caused by hydrogen penetration from the atmosphere into the material under tensile stress. The authors have shown the location of internal hydrogen atoms in the microstructure of some aluminum base alloys by means of tritium autoradiography in which the location of a hydrogen atom can be visualized as a silver particle produced through the photographic reaction by the {beta}-ray emitted from tritium: radio isotope of hydrogen. They also developed a unique testing machine which, being equipped with an ultra high vacuum chamber and a quadrupole mass spectrometer, can detect a trace amount of hydrogen gas evolved from the specimen on fracture. This paper describes a direct evidence of the correlation between hydrogen atom transport and dislocation glide in aluminum, which has been obtained by means of tritium autoradiography on a deformed sample.

  20. Glide-plane symmetry and superconducting gap structure of iron-based superconductors

    DOE PAGESBeta

    Wang, Yan; Berlijn, Tom; Hirschfeld, Peter J.; Scalapino, Douglas J.; Maier, Thomas A.

    2015-03-10

    We consider the effect of glide-plane symmetry of the Fe-pnictogen/chalcogen layer in Fe-based superconductors on pairing in spin fluctuation models. Recent theories propose that so-called η-pairing states with nonzero total momentum can be realized and possess such exotic properties as odd parity spin singlet symmetry and time-reversal symmetry breaking. Here we show that when there is orbital weight at the Fermi level from orbitals with even and odd mirror reflection symmetry in z, η pairing is inevitable; however, we conclude from explicit calculation that the gap function appearing in observable quantities is identical to that found in earlier pseudocrystal momentummore » calculations with 1 Fe per unit cell.« less

  1. Acetylcholinesterase-Inhibiting Activity of Pyrrole Derivatives from a Novel Marine Gliding Bacterium, Rapidithrix thailandica

    PubMed Central

    Sangnoi, Yutthapong; Sakulkeo, Oraphan; Yuenyongsawad, Supreeya; Kanjana-opas, Akkharawit; Ingkaninan, Kornkanok; Plubrukarn, Anuchit; Suwanborirux, Khanit

    2008-01-01

    Acetylcholinesterase-inhibiting activity of marinoquinoline A (1), a new pyrroloquinoline from a novel species of a marine gliding bacterium Rapidithrix thailandica, was assessed (IC50 4.9 μM). Two related pyrrole derivatives, 3-(2′-aminophenyl)-pyrrole (3) and 2,2-dimethyl-pyrrolo-1,2-dihydroquinoline (4), were also isolated from two other strains of R. thailandica. The isolation of 3 from a natural source is reported here for the first time. Compound 4 was proposed to be an isolation artifact derived from 3. The two isolated compounds were virtually inactive in the acetylcholinesterase-inhibitory assay (enzyme inhibition < 30% at 0.1 g L−1). PMID:19172195

  2. Gravity effects on a gliding arc in four noble gases: from normal to hypergravity

    NASA Astrophysics Data System (ADS)

    Potočňáková, L.; Šperka, J.; Zikán, P.; van Loon, J. J. W. A.; Beckers, J.; Kudrle, V.

    2015-04-01

    A gliding arc in four noble gases (He, Ne, Ar, Kr) has been studied under previously unexplored conditions of varying artificial gravity, from normal 1 g gravity up to 18 g hypergravity. Significant differences, mainly the visual thickness of the plasma channel, its maximum elongation and general sensitivity to hypergravity conditions, were observed between the discharges in individual gases, resulting from their different atomic weights and related quantities, such as heat conductivity or ionisation potential. Generally, an increase of the artificial gravity level leads to a faster plasma channel movement thanks to stronger buoyant force and a decrease of maximum height reached by the channel due to more intense losses of heat and reactive species. In relation to this, an increase in current and a decrease in absorbed power was observed.

  3. Measurements of 3D slip velocities and plasma column lengths of a gliding arc discharge

    SciTech Connect

    Zhu, Jiajian; Gao, Jinlong; Ehn, Andreas; Aldén, Marcus; Li, Zhongshan E-mail: alpers@ma.tum.de; Moseev, Dmitry; Kusano, Yukihiro; Salewski, Mirko; Alpers, Andreas E-mail: alpers@ma.tum.de; Gritzmann, Peter; Schwenk, Martin

    2015-01-26

    A non-thermal gliding arc discharge was generated at atmospheric pressure in an air flow. The dynamics of the plasma column and tracer particles were recorded using two synchronized high-speed cameras. Whereas the data analysis for such systems has previously been performed in 2D (analyzing the single camera image), we provide here a 3D data analysis that includes 3D reconstructions of the plasma column and 3D particle tracking velocimetry based on discrete tomography methods. The 3D analysis, in particular, the determination of the 3D slip velocity between the plasma column and the gas flow, gives more realistic insight into the convection cooling process. Additionally, with the determination of the 3D slip velocity and the 3D length of the plasma column, we give more accurate estimates for the drag force, the electric field strength, the power per unit length, and the radius of the conducting zone of the plasma column.

  4. Investigation of hydrocarbon oil transformation by gliding arc discharge: comparison of batch and recirculated configurations

    NASA Astrophysics Data System (ADS)

    Whitehead, J. Christopher; Prantsidou, Maria

    2016-04-01

    The degradation of liquid dodecane was studied in a gliding arc discharge (GAD) of humid argon or nitrogen. A batch or recirculating configuration was used. The products in the gaseous and liquid phase were analysed by infrared and chromatography and optical emission spectroscopy was used to identify the excited species in the discharge. The best degradation performance comes from the use of humid N2 but a GAD of humid argon produces fewer gas-phase products but more liquid-phase end-products. A wide range of products such as heavier saturated or unsaturated hydrocarbons both aliphatic and aromatic, and oxidation products mainly alcohols, but also aldehydes, ketones and esters are produced in the liquid-phase. The recirculating treatment mode is more effective than the batch mode increasing the reactivity and changing the product selectivities. Overall, the study shows promising results for the organic liquid waste treatment, especially in the recirculating mode.

  5. Optimal heading change with minimum energy loss for a hypersonic gliding vehicle

    NASA Technical Reports Server (NTRS)

    Calise, Anthony J.; Bae, Gyoung H.

    1987-01-01

    A three state model is presented for analyzing the problem of optimal changes in heading with minimum energy loss for a hypersonic gliding vehicle. A further model order reduction to a single state model is examined using singular perturbation theory. The optimal solution for the reduced problem defines an optimal altitude profile dependent on the current energy of the vehicle, and the corresponding optimal lift and bank angle. A separate boundary layer analysis, based on an expansion of the necessary conditions about the reduced solution, is used to account for altitude and flight path angle dynamics and to derive a guidance law in feedback form. The guidance law is evaluated for a hypothetical vehicle.

  6. Complete genome sequence of the gliding, heparinolytic Pedobacter saltans type strain (113T)

    SciTech Connect

    Liolios, Konstantinos; Sikorski, Johannes; Lu, Megan; Nolan, Matt; Lapidus, Alla L.; Lucas, Susan; Hammon, Nancy; Deshpande, Shweta; Cheng, Jan-Fang; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne A.; Pitluck, Sam; Huntemann, Marcel; Ivanova, N; Pagani, Ioanna; Mavromatis, K; Ovchinnikova, Galina; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Land, Miriam L; Hauser, Loren John; Brambilla, Evelyne-Marie; Kotsyurbenko, Oleg; Rohde, Manfred; Tindall, Brian; Abt, Birte; Goker, Markus; Detter, J. Chris; Woyke, Tanja; Bristow, James; Eisen, Jonathan; Markowitz, Victor; Hugenholtz, Philip; Klenk, Hans-Peter; Kyrpides, Nikos C

    2011-01-01

    Pedobacter saltans Steyn et al. 1998 is one of currently 32 species in the genus Pedobacter within the family Sphingobacteriaceae. The species is of interest for its isolated location in the tree of life. Like other members of the genus P. saltans is heparinolytic. Cells of P. saltans show a peculiar gliding, dancing motility and can be distinguished from other Pedobacter strains by their ability to utilize glycerol and the inability to assimilate D-cellobiose. The ge- nome presented here is only the second completed genome sequence of a type strain from a member of the family Sphingobacteriaceae to be published. The 4,635,236 bp long genome with its 3,854 protein-coding and 67 RNA genes consists of one chromosome, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  7. Mycoplasma hyopneumoniae and Mycoplasma flocculare differential domains from orthologous surface proteins induce distinct cellular immune responses in mice.

    PubMed

    Leal, Fernanda Munhoz Dos Anjos; Virginio, Veridiana Gomes; Martello, Carolina Lumertz; Paes, Jéssica Andrade; Borges, Thiago J; Jaeger, Natália; Bonorino, Cristina; Ferreira, Henrique Bunselmeyer

    2016-07-15

    Mycoplasma hyopneumoniae and Mycoplasma flocculare are two genetically close species found in the swine respiratory tract. Despite their similarities, while M. hyopneumoniae is the causative agent of porcine enzootic pneumonia, M. flocculare is a commensal bacterium. Genomic and transcriptional comparative analyses so far failed to explain the difference in pathogenicity between these two species. We then hypothesized that such difference might be, at least in part, explained by amino acid sequence and immunological or functional differences between ortholog surface proteins. In line with that, it was verified that approximately 85% of the ortholog surface proteins from M. hyopneumoniae 7448 and M. flocculare present one or more differential domains. To experimentally assess possible immunological implications of this kind of difference, the extracellular differential domains from one pair of orthologous surface proteins (MHP7448_0612, from M. hyopneumoniae, and MF_00357, from M. flocculare) were expressed in E. coli and used to immunize mice. The recombinant polypeptides (rMHP61267-169 and rMF35767-196, respectively) induced distinct cellular immune responses. While, rMHP61267-169 induced both Th1 and Th2 responses, rMF35767-196 induced just an early pro-inflammatory response. These results indicate that immunological properties determined by differential domains in orthologous surface protein might play a role in pathogenicity, contributing to elicit specific and differential immune responses against each species. PMID:27283856

  8. Complete Genome Sequence of Mycoplasma flocculare Strain Ms42T (ATCC 27399T).

    PubMed

    Calcutt, Michael J; Foecking, Mark F; Heidari, Manijeh B; McIntosh, Mark A

    2015-01-01

    Mycoplasma flocculare is a commensal or low-virulence pathogen of swine. The complete 778,866-bp genome sequence of M. flocculare strain Ms42(T) has been determined, enabling further comparison to genomes of the closely related pathogen Mycoplasma hyopneumoniae. The absence of the p97 and glpD genes may contribute to the attenuated virulence of M. flocculare. PMID:25767245

  9. Effects of mycoplasma contamination on phenotypic expression of mitochondrial mutants in human cells

    SciTech Connect

    Doersen, C.J.; Stanbridge, E.J.

    1981-04-01

    HeLa cells sensitive to the mitochondrial protein synthesis inhibitors erythromycin (ERY) and chloramphenicol (CAP) and HeLa variants resistant to the effects of these drugs were purposefully infected with drug-sensitive and -resistnat mycoplasma strains. Mycoplasma hyorhinis and the ERY-resistant strain of Mycoplasma orale, MO-ERY/sup r/, did not influence the growth of HeLa and ERY-resistant ERY2301 cells in the presence or absence of ERY. M. hyorhinis also did not affect the growth of HeLa and CAP-resistant Cap-2 cells in the presence or absence of CAP. However, both HeLa and Cap-2 cells infected with the CAP-resistant strain of M. hyorhinis, MH-CAP/sup r/, were more sensitive to the cytotoxix effect of CAP. This maybe due to the glucose dependence of the cells, which was compromised by the increased utilization of glucose by MH-CAP/sup r/ in these infected cell cultures. In vitro protein synthesis by isolated mitochondria was significantly altered by mycoplasma infection of the various cell lines. A substantial number of mycoplasmas copurified with the mitochondria, resulting in up to a sevenfold increase in the incorporation of (/sup 3/H)leucine into the trichloroacetic acid-insoluble material. More importantly, the apparent drug sensitivity or resistance of mitchondrial preparations from mycoplasma-infected cells reflected the drug sensitivity or resistance of the contaminating mycoplasmas. These results illustrate the hazards in interpreting mitochondrial protein synthesis data derived from mycoplasma-infected cell lines, particularly putative mitochondrially encoded mutants resistant to inhibitors of mitochondrial protein synthesis.

  10. Complete Genome Sequence of Mycoplasma flocculare Strain Ms42T (ATCC 27399T)

    PubMed Central

    Foecking, Mark F.; Heidari, Manijeh B.; McIntosh, Mark A.

    2015-01-01

    Mycoplasma flocculare is a commensal or low-virulence pathogen of swine. The complete 778,866-bp genome sequence of M. flocculare strain Ms42T has been determined, enabling further comparison to genomes of the closely related pathogen Mycoplasma hyopneumoniae. The absence of the p97 and glpD genes may contribute to the attenuated virulence of M. flocculare. PMID:25767245

  11. Genome Sequences of Two Tunisian Field Strains of Avian Mycoplasma, M. meleagridis and M. gallinarum

    PubMed Central

    Yacoub, Elhem; Sirand-Pugnet, Pascal; Barré, Aurélien; Blanchard, Alain; Hubert, Christophe; Maurier, Florence; Bouilhol, Emmanuel

    2016-01-01

    Mycoplasma meleagridis and Mycoplasma gallinarum are bacteria that affect birds, but little is known about the genetic basis of their interaction with chickens and other poultry. Here, we sequenced the genomes of M. meleagridis strain MM_26B8_IPT and M. gallinarum strain Mgn_IPT, both isolated from chickens showing respiratory symptoms, poor growth, reduction in hatchability, and loss of production. PMID:27313300

  12. Genome Sequences of Two Tunisian Field Strains of Avian Mycoplasma, M. meleagridis and M. gallinarum.

    PubMed

    Yacoub, Elhem; Sirand-Pugnet, Pascal; Barré, Aurélien; Blanchard, Alain; Hubert, Christophe; Maurier, Florence; Bouilhol, Emmanuel; Ben Abdelmoumen Mardassi, Boutheina

    2016-01-01

    Mycoplasma meleagridis and Mycoplasma gallinarum are bacteria that affect birds, but little is known about the genetic basis of their interaction with chickens and other poultry. Here, we sequenced the genomes of M. meleagridis strain MM_26B8_IPT and M. gallinarum strain Mgn_IPT, both isolated from chickens showing respiratory symptoms, poor growth, reduction in hatchability, and loss of production. PMID:27313300

  13. Epidemiology of Ureaplasma urealyticum and Mycoplasma hominis in the semen of male outpatients with reproductive disorders

    PubMed Central

    Zhu, Xiaofei; Li, Min; Cao, Huiling; Yang, Xuewen; Zhang, Chunbing

    2016-01-01

    The aim of the present study was to investigate the association between Mycoplasma infection and infertility in male outpatients among a Chinese population. Epidemiological data, including prevalence, age distribution and antibiotic resistance profile of patients with an Ureaplasma urealyticum or Mycoplasma hominis infection were collected between 2009 and 2012. Among the 7,374 individuals analyzed, 3,225 patients (43.7%) were determined to be positive for infection with U. urealyticum, M. hominis or for both Mycoplasmas. Among the positive cultures, U. urealyticum was detected most frequently, while M. hominis was rarely found. The age range of 25–34 years was the preferred period for the positive detection. Tetracyclines and josamycin were the most effective agents against both genital Mycoplasmas, including in the case of co-infection. Macrolides (erythromycin, roxithromycin, azithromycin, clarithromycin except for josamycin) were effective against the majority of U. urealyticum clinical isolates, but were naturally resisted by M. hominis in this study. Fluoroquinolones had the lowest activity against U. urealyticum, particularly in cases of M. hominis co-infection. Furthermore, fluoroquinolones showed a similar pattern of drug resistance against M. hominis to that of U. urealyticum. Antibiotic resistance did not vary significantly over the test period. Notably, an elevated multi-drug resistance rate was observed in patients co-infected with both Mycoplasmas. In light of the epidemiological characteristics of genital Mycoplasmas in male infertility patients, the present results may aid Chinese clinicians to implement rational drug usage and avoid the overuse of antibiotics.

  14. The origin of the 'Mycoplasma mycoides cluster' coincides with domestication of ruminants.

    PubMed

    Fischer, Anne; Shapiro, Beth; Muriuki, Cecilia; Heller, Martin; Schnee, Christiane; Bongcam-Rudloff, Erik; Vilei, Edy M; Frey, Joachim; Jores, Joerg

    2012-01-01

    The 'Mycoplasma mycoides cluster' comprises the ruminant pathogens Mycoplasma mycoides subsp. mycoides the causative agent of contagious bovine pleuropneumonia (CBPP), Mycoplasma capricolum subsp. capripneumoniae the agent of contagious caprine pleuropneumonia (CCPP), Mycoplasma capricolum subsp. capricolum, Mycoplasma leachii and Mycoplasma mycoides subsp. capri. CBPP and CCPP are major livestock diseases and impact the agricultural sector especially in developing countries through reduced food-supply and international trade restrictions. In addition, these diseases are a threat to disease-free countries. We used a multilocus sequence typing (MLST) approach to gain insights into the demographic history of and phylogenetic relationships among the members of the 'M. mycoides cluster'. We collected partial sequences from seven housekeeping genes representing a total of 3,816 base pairs from 118 strains within this cluster, and five strains isolated from wild Caprinae. Strikingly, the origin of the 'M. mycoides cluster' dates to about 10,000 years ago, suggesting that the establishment and spread of the cluster coincided with livestock domestication. In addition, we show that hybridization and recombination may be important factors in the evolutionary history of the cluster. PMID:22558362

  15. Cloning, expression, and antigenic characterization of recombinant protein of Mycoplasma gallisepticum expressed in Escherichia coli.

    PubMed

    Rocha, T S; Tramuta, C; Catania, S; Matucci, A; Giuffrida, M G; Baro, C; Profiti, M; Bertolotti, L; Rosati, S

    2015-04-01

    Mycoplasma gallisepticum (MG) is a member of the most important avian mycoplasmas, causing chronic respiratory disease in chickens and leading to important economic losses in the poultry industry. Recombinant technology represents a strategic approach used to achieve highly reliable and specific diagnostic tests in veterinary diseases control: in particular this aspect is crucial for confirming mycoplasma infection and for maintaining mycoplasma-free breeder flocks. In this study, we identified a component of the pyruvate dehydrogenase dihydrolipoamide acetyltransferase (i.e., E2) protein by 2-dimensional electrophoresis (2-DE), characterized it in immunoblotting assays, and analyzed its recombinant (r-E2) in a rec-ELISA test. For full-length protein expression in Escherichia coli (EC) a point mutation was introduced. A rabbit antiserum produced against r-E2 was tested in a Western Blot using different samples of Mycoplasma species. The results showed the applicability of site-directed mutagenesis, with a good yield of the r-E2 after purification. Also, anti-E2 serum reacted with all the tested MG strains showing no cross reaction with other mycoplasmas. The developed E2 ELISA test was capable of detecting MG antibodies in the sera examined. Those results demonstrate the antigenic stability of the E2 protein which could represent a recombinant antigen with potential diagnostic applications. PMID:25667423

  16. Interaction of Mycoplasma pneumoniae with human lung fibroblasts: characterization of the in vitro model.

    PubMed Central

    Gabridge, M G; Taylor-Robinson, D; Davies, H A; Dourmashkin, R R

    1979-01-01

    The interaction of pathogenic Mycoplasma pneumoniae and host cells was studied in cell cultures of MRC-5 human lung fibroblasts. A comparison of results obtained with fibroblasts in a monolayer format and with hamster tracheal explant cultures indicated that the former can bind significantly larger numbers of mycoplasmas. In addition, the attachment was 96% specific, that is, mediated through a neuraminidase-sensitive receptor on the host cell. Uptake of mycoplasmas was directly related to the number of mycoplasma cells present in the inoculum, and attachment was virtually complete within a 30-min period at 37 degrees C. High doses of M. pneumoniae induced a marked cytopathic effect, whereas doses of less than or equal to 10(6) colony-forming units per ml produced grossly observable cell damage that was moderate and variable. Transmission electron microscopy studies indicated that attachment of M. pneumoniae to the surface of lung fibroblasts occurred with the specialized terminal structure or binding site oriented closest to the epithelial cell surface. The filamentous mycoplasma cells were spatially arranged in several configurations and were not limited to a vertical orientation. The advantages and disadvantages of human lung fibroblast monolayer cultures, in reference to other in vitro models are discussed. A new mycoplasma agar medium (G-200 agar) with a defined tissue culture base and 10% horse serum is also described. Images PMID:113348

  17. Frequency and antimicrobial sensitivity of Ureaplasma urealyticum and Mycoplasma hominis in patients with vaginal discharge.

    PubMed

    Díaz, Leonor; Cabrera, Luis E; Fernández, Tania; Ibáñez, Inailay; Torres, Yulian; Obregón, Yakelí; Rivero, Yanelys

    2013-10-01

    Determination of antimicrobial sensitivity helps establish adequate treatment and avoids future genital tract diseases in women of fertile age. In Cuba, prevalence of mycoplasma in patients with vaginal discharge is unknown. The objective of this research was to determine frequency and antimicrobial sensitivity of Ureaplasma urealyticum and Mycoplasma hominis in women with vaginal discharge through analysis of laboratory data from vaginal smears from 255 patients referred to the Municipal Hygiene and Epidemiology Center in Güines, Mayabeque Province, Cuba. Mycoplasma System Plus (Italy) was used for detection, identification, count and sensitivity testing. The finding of mycoplasmas in almost two thirds of specimens examined suggests that the sexually active female population should be screened for these bacteria and that barrier contraception methods should be promoted to decrease their spread and prevent longterm sequelae. Such updating of local patterns of antimicrobial resistance supports decision making for best treatment options in patients with these infections. Our results should help clinicians in our area choose an antibiotic, and also confirm the utility of Mycoplasma System Plus for mycoplasma research in resource-scarce settings, to benefit individual and population health. PMID:24253351

  18. Investigations into the seasonal presence of Mycoplasma species in fattening lambs.

    PubMed

    Fernández, Sara; Galapero, Javier; Rey, Joaquín; Pérez, Carlos Javier; Ramos, Alfonso; Rosales, Rubén; Ayling, Roger; Alonso, Juan Manuel; Gómez, Luis

    2016-06-01

    The presence of infection with Mycoplasma species in association with lung consolidation, environmental temperature and relative humidity was investigated in 410 clinically healthy fattening lambs from five different feedlots in Extremadura (southwestern Spain). Isolates of Mycoplasma species were obtained (n= 117), including Mycoplasma ovipneumoniae (n = 18) and Mycoplasma arginini (n = 99). Two seasonal periods were identified. The first period, which included February, March, September, October, and November, had an average temperature of 17.5 ± 4.7 °C and a relative humidity of 61.3 ± 15.8%. The second seasonal period, which included the months from April to August, had an average temperature of 22.9 ± 5.5 °C and a relative humidity of 48.4 ± 10.7%. Most Mycoplasma species were isolated from the second seasonal period, indicating that higher temperatures and lower relative humidity favour the presence of Mycoplasma species. M. arginini was also associated with lung consolidation. PMID:27256030

  19. Adenovirus and mycoplasma infection in an ornate box turtle (Terrapene ornata ornata) in Hungary.

    PubMed

    Farkas, Szilvia L; Gál, János

    2009-07-01

    A female, adult ornate box turtle (Terrapene ornata ornata) with fatty liver was submitted for virologic examination in Hungary. Signs of an adenovirus infection including degeneration of the liver cells, enlarged nuclei and intranuclear inclusion bodies were detected by light microscopic examination. The presence of an adenovirus was later confirmed by obtaining partial sequence data from the adenoviral DNA-dependent DNA-polymerase. Phylogenetic analyses revealed that this novel chelonian adenovirus was distinct from previously described reptilian adenoviruses, not belonging to any of the recognized genera of the family Adenoviridae. As a part of the routine diagnostic procedure for chelonians the detection of herpes-, rana- and iridoviruses together with Mycoplasma spp. was attempted. Amplicons were generated by a general mycoplasma polymerase chain reaction (PCR) targeting the 16S/23S ribosomal RNA (rRNA) intergenic spacer region, as well as, a specific Mycoplasma agassizii PCR targeting the 16S rRNA gene. Based on the analyses of partial sequences of the 16S rRNA gene, the Mycoplasma sp. of the ornate box turtle seemed to be identical with the recently described eastern box turtle (Terrapene carolina carolina) Mycoplasma sp. This is the first report of a novel chelonian adenovirus and a mycoplasma infection in an ornate box turtle (T. ornata ornata) in Europe. PMID:19375875

  20. Ageing-related changes in Mycoplasma canadense membranes.

    PubMed

    Muñoz, G E; Sotomayor, C P

    1992-01-01

    Fluidity and composition of cell membranes during progression of Mycoplasma canadense cultures grown in a serum-free medium was assessed. The fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene at 25 degrees C of intact cells and liposomes in the exponential and stationary phases of growth was compared. A decrease in fluidity and an increase in the ratio of saturated to unsaturated fatty acids was detected in cell membranes on aging. Nevertheless, membrane density remained unaltered although the molar ratio of cholesterol to phospholipids decreased. It is proposed that the increase in lipid order is primarily due to the increase in the ratio of saturated to unsaturated membrane fatty acids, being the diminished molar ratio of cholesterol to phospholipids involved in the reduced unsaturated fatty acid uptake. PMID:1541600

  1. Mycoplasma felis as a cause of pleuritis in horses.

    PubMed

    Ogilvie, T H; Rosendal, S; Blackwell, T E; Rostkowski, C M; Julian, R J; Ruhnke, L

    1983-06-15

    Mycoplasma felis was the only organism recovered from the thoracic cavity of a horse with pleuritis. Large numbers of mildly degenerative neutrophils were in the pleural fluid. The horse developed a serologic response to M felis and recovered during hospitalization. Experimentally, a pony was inoculated in the thoracic cavity with a pure culture of the M felis isolate suspended in the pony's serum. A control pony was inoculated with serum only. Within 48 hours, the principal pony developed fever, increased respiratory rate, pleural effusion, and signs of pain. A highly cellular exudate with nondegenerative neutrophils and large numbers of M felis was recovered from the thoracic cavity. The control pony remained normal. The principal pony developed an antibody response to M felis. The control pony did not. Fourteen days after inoculation, both ponies were euthanatized. Necropsy revealed pleural inflammation in the principal pony. Pleural lesions were not found in the control pony. PMID:6874502

  2. Detection of Mycoplasma agassizii in the Texas Tortoise (Gopherus berlandieri)

    USGS Publications Warehouse

    Guthrie, Amanda L.; White, C. LeAnn; Brown, Mary B.; deMaar, Thomas W.

    2013-01-01

    Mycoplasma agassizii causes upper respiratory tract disease (URTD) in Texas tortoises (Gopherus berlandieri). To determine exposure to and shedding of M. agassizii, we collected blood samples and nasal swabs from 40 free-ranging Texas tortoises on public and private lands in Texas, USA, from May to October 2009. We used an enzyme-linked immunosorbent assay (ELISA) to detect M. agassizii–specific antibodies. Eleven (28%) tortoises were antibody positive, three (8%) were suspect, and the remaining 26 (65%) were negative. Nasal lavage samples were collected from 35 of the 40 tortoises for M. agassizii culture and PCR to detect shedding of M. agassizii. Current infection with M. agassizii was confirmed in one tortoise that had mild clinical signs of URTD and was positive by ELISA (antibody titer >512), PCR, and culture. The clinical isolate was confirmed as M. agassizii by restriction fragment length polymorphism and immunobinding.

  3. Stevens-Johnson syndrome associated with Mycoplasma pneumoniae infections.

    PubMed

    Sontheimer, R D; Garibaldi, R A; Krueger, G G

    1978-02-01

    The Stevens-Johnson syndrome is a multisystem inflammatory disorder associated with a widespread erythematous eruption that can result in death. Although usually considered a pediatric disease, this syndrome frequently affects adults. There are many etiologic associations including drugs and infections; however, the pathophysiology of the syndrome remains obscure. Treatment at present is symptomatic and supportive. Although frequently used, the beneficial role of corticosteroids in this syndrome remains to be proved. The case report describes a young woman who after treatment with several drugs developed the Stevens-Johnson syndrome in association with a Mycoplasma pneumoniae infection. We include a brief review of the literature with emphasis on the Stevens-Johnsons syndrome's association with M pneumoniae infections. Those caring for patients with skin disease should be aware of the association between such treatable infections and this syndrome. PMID:629550

  4. Mycoplasma pneumoniae Epidemiology in England and Wales: A National Perspective

    PubMed Central

    Brown, Rebecca J.; Nguipdop-Djomo, Patrick; Zhao, Hongxin; Stanford, Elaine; Spiller, O. Brad; Chalker, Victoria J.

    2016-01-01

    Investigations of patients with suspected Mycoplasma pneumoniae infection have been undertaken in England since the early 1970s. M. pneumoniae is a respiratory pathogen that is a common cause of pneumonia and may cause serious sequelae such as encephalitis and has been documented in children with persistent cough. The pathogen is found in all age groups, with higher prevalence in children aged 5–14 years. In England, recurrent epidemic periods have occurred at ~4-yearly intervals. In addition, low-level sporadic infection occurs with seasonal peaks from December to February. Voluntarily reports from regional laboratories and hospitals in England from 1975 to 2015 were collated by Public Health England for epidemiological analysis. Further data pertaining cases of note and specimens submitted to Public Health England from 2005 to 2015 for confirmation, molecular typing is included. PMID:26909073

  5. MLVA typing of Mycoplasma hyopneumoniae bacterins and field strains.

    PubMed

    Tamiozzo, P; Zamora, R; Lucchesi, P M A; Estanguet, A; Parada, J; Carranza, A; Camacho, P; Ambrogi, A

    2015-01-01

    Because of the lack of information about both the genetic characteristics of Mycoplasma hyopneumoniae commercial vaccines and their relationship with field strains, the authors attempted to identify genetic subtypes of some M hyopneumoniae bacterins, and to compare them with M. hyopneumoniae field strains. Six commercial M hyopneumoniae bacterins and 28 bronchoalveolar lavages from pigs at slaughter from three herds were analysed by Multiple-Locus Variable number tandem repeat Analysis (MLVA) on p146R1, p146R3, H4, H5 and p95 loci. The results obtained showed the presence of more than one M hyopneumoniae genotype in some pigs and also in one of the bacterins analysed. It is also worth noting that MLVA typing allowed the distinction among circulating field strains and also when comparing them with vaccine strains, which, knowing the relatedness among them, could be useful in the research of the efficacy of the vaccines. PMID:26495127

  6. Mycoplasma bovis: Mechanisms of Resistance and Trends in Antimicrobial Susceptibility.

    PubMed

    Lysnyansky, Inna; Ayling, Roger D

    2016-01-01

    Mycoplasma bovis is a cell-wall-less bacterium and belongs to the class Mollicutes. It is the most important etiological agent of bovine mycoplasmoses in North America and Europe, causing respiratory disease, mastitis, otitis media, arthritis, and reproductive disease. Clinical disease associated with M. bovis is often chronic, debilitating, and poorly responsive to antimicrobial therapy, resulting in significant economic loss, the full extent of which is difficult to estimate. Until M. bovis vaccines are universally available, sanitary control measures and antimicrobial treatment are the only approaches that can be used in attempts to control M. bovis infections. However, in vitro studies show that many of the current M. bovis isolates circulating in Europe have high minimum inhibitory concentrations (MIC) for many of the commercially available antimicrobials. In this review we summarize the current MIC trends indicating the development of antimicrobial resistance in M. bovis as well as the known molecular mechanisms by which resistance is acquired. PMID:27199926

  7. Mycoplasmas hyorhinis in different regions of cuba. diagnosis

    PubMed Central

    Lobo, Evelyn; Poveda, Carlos; Gupta, Rakesh; Suarez, Alejandro; Hernández, Yenney; Ramírez, Ana; Poveda, José B.

    2011-01-01

    M. hyorhinis is considered one of the etiological agents of arthritis in sucking pigs, but recently as seen, some strains can produce pneumonia that could not be distinguished from the mycoplasmosis caused by M. hyopneumoniae. The study was conducted to research the presence of Mycoplasma hyorhinis (M. hyorhinis ) in different regions of the country from exudates of pig lungs with typical EP lesions. Exudates from 280 pig lungs with typical EP lesions were studied using molecular techniques such as PCR, real time PCR and amplification of the 16S-23S rRNA. It was detected that the 66% of the samples studied resulted positive to M. hyorhinis, and the presence of this species was detected in all the provinces. Amplification and studies on the intergenic region 16S-23S of M. hyorhinis rRNA demonstrated the existing variability among strains of a same species. This study is the first report on M. hyorhinis detection in Cuba. PMID:24031686

  8. Mycoplasma genitalium: Is It a Sexually Transmitted Pathogen?

    PubMed

    Manhart, Lisa E; Kay, Noa

    2010-07-01

    Mycoplasma genitalium is an emerging pathogen that has been detected in the male and female reproductive tracts. It is an established cause of nongonococcal urethritis and evidence linking it to cervicitis, endometritis, and tubal factor infertility is accumulating. Whether a pathogen is sexually transmitted has important implications for clinical management because partner management strategies are an essential part of the treatment plan for sexually transmitted infections. However, mere detection in the genital tract and associations with reproductive tract disease are insufficient to conclude that an organism is sexually transmitted. Therefore, to assess whether M. genitalium is sexually transmitted, we evaluated the literature in terms of associations with established risk factors for other sexually transmitted infections, comparisons of sexually experienced individuals to nonsexually experienced individuals, consideration of other modes of transmission, assessment of concordant infection status among sexual partners, and examination of molecular strain typing in concordantly infected partners. PMID:21308546

  9. Transbilayer distribution of sterols in mycoplasma membranes: a review.

    PubMed Central

    Bittman, R.; Clejan, S.; Rottem, S.

    1983-01-01

    The polyene antibiotic, filipin, binds to 3 beta-hydroxysterols. The initial rate of filipin-sterol association, monitored in a stopped-flow spectrophotometer, was first order in each reacting partner. The ratio of rate constants in intact mycoplasma cells relative to isolated, unsealed membranes provides an estimate of sterol distribution in the membrane bilayer. Cholesterol is distributed symmetrically in the bilayer of M. gallisepticum cells from the early exponential phase. However, in the M. capricolum membrane two-thirds of the unesterified cholesterol is localized in the outer leaflet; alkyl-sterols are distributed predominantly in the external monolayer. Cholesterol is translocated rapidly in the bilayer of M. capricolum cells. Exogenous phospholipids incorporated into the membrane had no effect on the cholesterol distribution in M. capricolum. PMID:6382819

  10. Mycoplasma bovis: Mechanisms of Resistance and Trends in Antimicrobial Susceptibility

    PubMed Central

    Lysnyansky, Inna; Ayling, Roger D.

    2016-01-01

    Mycoplasma bovis is a cell-wall-less bacterium and belongs to the class Mollicutes. It is the most important etiological agent of bovine mycoplasmoses in North America and Europe, causing respiratory disease, mastitis, otitis media, arthritis, and reproductive disease. Clinical disease associated with M. bovis is often chronic, debilitating, and poorly responsive to antimicrobial therapy, resulting in significant economic loss, the full extent of which is difficult to estimate. Until M. bovis vaccines are universally available, sanitary control measures and antimicrobial treatment are the only approaches that can be used in attempts to control M. bovis infections. However, in vitro studies show that many of the current M. bovis isolates circulating in Europe have high minimum inhibitory concentrations (MIC) for many of the commercially available antimicrobials. In this review we summarize the current MIC trends indicating the development of antimicrobial resistance in M. bovis as well as the known molecular mechanisms by which resistance is acquired. PMID:27199926

  11. MLVA typing of Mycoplasma hyopneumoniae bacterins and field strains

    PubMed Central

    Tamiozzo, P.; Zamora, R.; Lucchesi, P. M. A.; Estanguet, A.; Parada, J.; Carranza, A.; Camacho, P.; Ambrogi, A.

    2015-01-01

    Because of the lack of information about both the genetic characteristics of Mycoplasma hyopneumoniae commercial vaccines and their relationship with field strains, the authors attempted to identify genetic subtypes of some M hyopneumoniae bacterins, and to compare them with M. hyopneumoniae field strains. Six commercial M hyopneumoniae bacterins and 28 bronchoalveolar lavages from pigs at slaughter from three herds were analysed by Multiple-Locus Variable number tandem repeat Analysis (MLVA) on p146R1, p146R3, H4, H5 and p95 loci. The results obtained showed the presence of more than one M hyopneumoniae genotype in some pigs and also in one of the bacterins analysed. It is also worth noting that MLVA typing allowed the distinction among circulating field strains and also when comparing them with vaccine strains, which, knowing the relatedness among them, could be useful in the research of the efficacy of the vaccines. PMID:26495127

  12. Wildlife surveillance during a Mycoplasma gallisepticum epornitic in domestic turkeys.

    PubMed

    Stallknecht, D E; Johnson, D C; Emory, W H; Kleven, S H

    1982-01-01

    During a major Mycoplasma gallisepticum (MG) epornitic in domestic turkeys, tracheal swabs were collected and cultured from 477 and 770 potentially exposed wild mammals and birds, respectively. All culture attempts were negative. Serum-plate (SP) and hemagglutination-inhibition (HI) tests on 770 bird sera revealed low titers (less than or equal to 1:40) in 0.9% of tested house sparrows, 1.1% of brown-headed cowbirds, 35.7% of common grackles, 1.0% of starlings, and 16.6% of eastern meadowlarks. Low titers are believed to have resulted from birds feeding on contaminated litter and becoming sensitized. Wildlife species did not appear to be involved in transmission or maintenance of MG but may have been mechanical carriers of this pathogen. PMID:7159324

  13. Mycoplasma agassizii in Morafka's desert tortoise (Gopherus morafkai) in Mexico

    USGS Publications Warehouse

    Berry, Kristin H.; Brown, Mary B.; Vaughn, Mercy; Gowan, Timothy A.; Hasskamp, Mary Ann; Torres, Ma. Cristina Melendez

    2015-01-01

    We conducted health evaluations of 69 wild and 22 captive Morafka's desert tortoises (Gopherus morafkai) in Mexico between 2005 and 2008. The wild tortoises were from 11 sites in the states of Sonora and Sinaloa, and the captive tortoises were from the state-managed Centro Ecológico de Sonora Zoo in Hermosillo and a private residence in the town of Alamos. We tested 88 tortoises for mycoplasmal upper respiratory tract disease (URTD) using enzyme-linked immunosorbent assays for specific antibody and by culture and PCR for detection of Mycoplasma agassizii and Mycoplasma testudineum. Fifteen of 22 captive tortoises had one or more positive diagnostic test results for M. agassizii whereas no wild tortoises had positive tests. Tortoises with positive tests also had significantly more moderate and severe clinical signs of mycoplasmosis on beaks and nares compared to tortoises with negative tests. Captive tortoises also exhibited significantly more clinical signs of illness than did wild tortoises, including lethargy and moderate to severe ocular signs. The severity of trauma and diseases of the shell and integument did not differ significantly among tortoises by site; however, clinical signs of moderate to severe trauma and disease were more prevalent in older tortoises. Similar to research findings for other species in the genus Gopherusin the US, we found that URTD is an important disease in captive tortoises. If they escape or are released by intention or accident to the wild, captive tortoises are likely to pose risks to healthy, naïve wild populations.

  14. Mycoplasma pneumoniae, a trigger for Weston Hurst syndrome

    PubMed Central

    Verschoor, Chris P.; Bowdish, Dawn M.E.; Provias, John

    2016-01-01

    Objective: We report a case of Mycoplasma pneumoniae infection as one possible trigger for Weston Hurst syndrome (acute hemorrhagic leukoencephalitis), a rare disorder of microvascular injury often described as a postinfectious complication of an upper respiratory illness. Methods: This is a case of a 27-year-old man presenting with a Glasgow Coma Scale score of 3 and an acute head CT revealing extensive vasogenic edema in the right hemisphere associated with mass effect in the context of a recent upper respiratory illness. Right frontal biopsy was performed on day 2, which showed acute cerebritis, and the patient was aggressively treated with antibiotics. However, over the next 5 days from presentation, the vasogenic edema increased, leading ultimately to brain herniation and death. Results: A full autopsy was performed at 5 days from presentation, which showed areas of vessel wall fibrinoid necrosis throughout the right hemisphere as well as, but less so, in the left frontal lobe and pons. Chest x-ray on presentation revealed atypical pneumonia, blood tests were positive for cold agglutinins, and at full autopsy, there was myocarditis, all in keeping with recent M pneumoniae infection. DNA obtained from lung and diseased brain (postmortem) was positive for Mycoplasma providing more direct evidence for brain invasion by this organism as the ultimate trigger for Weston Hurst syndrome. Conclusions: This is a rare case report of Weston Hurst syndrome having both initial brain biopsy on day 2 and full autopsy results on day 5 of presentation revealing important clinical clues about the pathogenesis of this often fatal disorder. PMID:26819961

  15. Changes in corticosterone concentrations and behavior during Mycoplasma gallisepticum infection in house finches (Haemorhous mexicanus).

    PubMed

    Love, Ashley C; Foltz, Sarah L; Adelman, James S; Moore, Ignacio T; Hawley, Dana M

    2016-09-01

    Glucocorticoid stress hormones are important for energy mobilization as well as regulation of the immune system, and thus these hormones are particularly likely to both influence and respond to pathogen infection in vertebrates. In this study, we examined how the glucocorticoid stress response in house finches (Haemorhous mexicanus) interacts with experimental infection of the naturally-occurring bacterial pathogen, Mycoplasma gallisepticum (MG). We also investigated whether infection-induced concentrations of corticosterone (CORT), the primary glucocorticoid in birds, were associated with the expression of sickness behavior, the lethargy typically observed in vertebrates early in infection. We found that experimental infection with MG resulted in significantly higher CORT levels on day 5 post-infection, but this effect appeared to be limited to female house finches only. Regardless of sex, infected individuals with greater disease severity had the highest CORT concentrations on day 5 post-infection. House finches exposed to MG exhibited behavioral changes, with infected birds having significantly lower activity levels than sham-inoculated individuals. However, CORT concentrations and the extent of sickness behaviors exhibited among infected birds were not associated. Finally, pre-infection CORT concentrations were associated with reduced inflammation and pathogen load in inoculated males, but not females. Our results suggest that the house finch glucocorticoid stress response may both influence and respond to MG infection in sex-specific ways, but because we had a relatively low sample size of males, future work should confirm these patterns. Finally, manipulative experiments should be performed to test whether the glucocorticoid stress response acts as a brake on the inflammatory response associated with MG infection in house finches. PMID:27288634

  16. Mycoplasma corogypsi associated polyarthritis and tenosynovitis in black vultures (Coragyps atratus)

    PubMed Central

    Van Wettere, A. J.; Ley, D. H.; Scott, D. E.; Buckanoff, H. D.; Degernes, L. A.

    2013-01-01

    Three wild American black vultures (Coragyps atratus) were presented to rehabilitation centers with swelling of multiple joints, including elbows, stifles, hocks, and carpal joints, and of the gastrocnemius tendons. Cytological examination of the joint fluid exudate indicated heterophilic arthritis. Radiographic examination in 2 vultures demonstrated periarticular soft tissue swelling in both birds and irregular articular surfaces with subchondral bone erosion in both elbows in 1 bird. Prolonged antibiotic therapy administered in 2 birds did not improve the clinical signs. Necropsy and histological examination demonstrated a chronic lymphoplasmacytic arthritis involving multiple joints and gastrocnemius tenosynovitis. Articular lesions varied in severity and ranged from moderate synovitis and cartilage erosion and fibrillation to severe synovitis, diffuse cartilage ulceration, subchondral bone loss and/or sclerosis, pannus, synovial cysts, and epiphyseal osteomyelitis. No walled bacteria were observed or isolated from the joints. However, mycoplasmas polymerase chain reactions were positive in at least 1 affected joint from each bird. Mycoplasmas were isolated from joints of 1 vulture that did not receive antibiotic therapy. Sequencing of 16S rRNA gene amplicons from joint samples and the mycoplasma isolate identified Mycoplasma corogypsi in 2 vultures and was suggestive in the third vulture. Mycoplasma corogypsi identification was confirmed by sequencing the 16S-23S intergenic spacer region of mycoplasma isolates. This report provides further evidence that M. corogypsi is a likely cause of arthritis and tenosynovitis in American black vultures. Cases of arthritis and tenosynovitis in New World vultures should be investigated for presence of Mycoplasma spp, especially M. corogypsi. PMID:22903399

  17. Reduction of hydrogen peroxide accumulation and toxicity by a catalase from Mycoplasma iowae.

    PubMed

    Pritchard, Rachel E; Prassinos, Alexandre J; Osborne, John D; Raviv, Ziv; Balish, Mitchell F

    2014-01-01

    Mycoplasma iowae is a well-established avian pathogen that can infect and damage many sites throughout the body. One potential mediator of cellular damage by mycoplasmas is the production of H2O2 via a glycerol catabolic pathway whose genes are widespread amongst many mycoplasma species. Previous sequencing of M. iowae serovar I strain 695 revealed the presence of not only genes for H2O2 production through glycerol catabolism but also the first documented mycoplasma gene for catalase, which degrades H2O2. To test the activity of M. iowae catalase in degrading H2O2, we studied catalase activity and H2O2 accumulation by both M. iowae serovar K strain DK-CPA, whose genome we sequenced, and strains of the H2O2-producing species Mycoplasma gallisepticum engineered to produce M. iowae catalase by transformation with the M. iowae putative catalase gene, katE. H2O2-mediated virulence by M. iowae serovar K and catalase-producing M. gallisepticum transformants were also analyzed using a Caenorhabditis elegans toxicity assay, which has never previously been used in conjunction with mycoplasmas. We found that M. iowae katE encodes an active catalase that, when expressed in M. gallisepticum, reduces both the amount of H2O2 produced and the amount of damage to C. elegans in the presence of glycerol. Therefore, the correlation between the presence of glycerol catabolism genes and the use of H2O2 as a virulence factor by mycoplasmas might not be absolute. PMID:25127127

  18. Validation of nested PCR and a selective biochemical method as alternatives for mycoplasma detection.

    PubMed

    Cheong, Kyung Ah; Agrawal, Santosh Rani; Lee, Ai-Young

    2011-04-01

    Direct culture is the most common way to reliably detect mycoplasma, but it is not practical for the qualitative control of cell therapeutics because of the elaborate culture medium, the prolonged incubation time, and the large sample volumes. Here, we chose two alternative methods using commercial detection kits, the PCR mycoplasma detection kit with nested PCR and the selective biochemical method, MycoAlert(®), and validated them with the direct culture method as a reference. We tested eight mycoplasma species and five validation parameters: specificity, detection limit, robustness, repeatability, and ruggedness, based on the regulatory guidelines in the US Pharmacopoeia. All experiments were performed using fibroblasts spiked with mycoplasma. Specificity tests for both methods included all mycoplasma species, except Mycoplasma pneumonia and M. genitalium for the nested PCR and Ureaplasma urealyticum for the MycoAlert(®) assay. Regarding the detection limit, the nested PCR proved to be as sensitive as the direct culture method and more sensitive than the MycoAlert(®) assay. The predicted median for probit = 0.9 was 54 (44-76) CFU/ml for M. hyorhinis and 16 (13-23) CFU/ml for M. hominis by the nested PCR, but 431 (346-593) CFU/ml and 105 (87-142) CFU/ml, respectively, with MycoAlert(®). Changes in the concentration of reagents, reagent lot, or individual analysts did not influence the results of the examined methods. The results of this study support nested PCR as a valuable alternative for mycoplasma detection. PMID:20806253

  19. Widespread infection with hemotropic mycoplasmas in bats in Spain, including a hemoplasma closely related to "Candidatus Mycoplasma hemohominis".

    PubMed

    Millán, Javier; López-Roig, Marc; Delicado, Verónica; Serra-Cobo, Jordi; Esperón, Fernando

    2015-04-01

    Molecular analyses of blood samples revealed infection with hemoplasmas in 97% of 31 cave bats captured in three caves in North-Eastern Spain. The characterization of 1250 bp of the 16S rRNA gene in 29 of the positive bats identified two different groups of sequences. Twenty-two Schreibers' bats (Miniopterus schreibersii) and one long-eared bat (Myotis capaccinii) shared one group, composed of seven closely related sequences. These sequences showed an identity of about 97% with "Candidatus Mycoplasma hemohominis" and the phylogenetic branch including bat and human sequences showed a 100% bootstrap value, supporting a close phylogenetic relationship between these hemoplasmas. The second group, representing a potentially novel species, was composed of a single sequence shared by six Schreibers' bats that had 91% identity with the recently reported hemoplasma from little brown bats in North America. Large bat aggregations in roosting caves probably benefits intra and inter-species transmission explaining the high observed prevalence. PMID:25655409

  20. The Effect of Lift-Drag Ratio and Speed on the Ability to Position a Gliding Aircraft for a Landing on a 5,000-Foot Runway

    NASA Technical Reports Server (NTRS)

    Reeder, John P.

    1959-01-01

    Flight tests were made to determine the capability of positioning a gliding airplane for a landing on a 5,000-foot runway with special reference to the gliding flight of a satellite vehicle of fixed configuration upon reentry into the earth's atmosphere. The lift-drag ratio and speed of the airplane in the glides were varied through as large a range as possible. The results showed a marked tendency to undershoot the runway when the lift-drag ratios were below certain values, depending upon the speed in the glide. A straight line dividing the successful approaches from the undershoots could be drawn through a lift-drag ratio of about 3 at 100 knots and through a lift-drag ratio of about 7 at 185 knots. Provision of a drag device would be very beneficial, particularly in reducing the tendency toward undershooting at the higher speeds.

  1. Efficacy and safety of BrushPicks, a new cleaning aid, compared to the use of Glide floss.

    PubMed

    Yankell, Samuel L; Shi, Xiuren; Emling, Robert C

    2002-01-01

    The objective of this double-blind, four-week clinical study was to evaluate the efficacy of BrushPicks, a new cleaning aid, and Glide floss on the reduction of plaque area, gingivitis and bleeding on probing, and to monitor safety when these products were used in addition to toothbrushing with an ADA-Accepted toothbrush (Oral-B P35) and an ADA-Accepted fluoride-containing dentifrice (Crest Regular). No special instructions on or supervision of product use was conducted, other than requesting twice-a-day (morning and evening) use of the assigned products. Following a baseline examination, 63 qualifying adult male and female subjects from the Philadelphia, Pennsylvania area were randomized into two groups. Subjects were also told to use their assigned dental aid after each toothbrushing. Examinations for efficacy and safety were repeated after two and four weeks' use of the products. Sixty-two subjects completed all aspects of the study. There were no untoward side effects attributed to product use, reported or observed, at the two- or four-week examination times. At baseline, there were no significant differences in plaque, gingivitis or bleeding on probing mean scores between the BrushPicks and Glide floss groups. At the two- and four-week evaluation times, both the BrushPicks and Glide floss had numerically lower plaque scores compared to baseline levels. The only statistically significant reduction (p < 0.01) was in the BrushPicks group, comparing the week two mean with the baseline value. Gingivitis (GI) at four weeks was statistically (p < 0.05) lower in the BrushPicks group as compared to the Glide floss mean value. When the changes in scores from baseline to two weeks and to four weeks were assessed, the mean GI score for the Glide floss group was significantly lower at two weeks (p < 0.01) compared to baseline, and also from two weeks to four weeks (p < 0.001). The change in mean GI score for the Glide floss group from baseline to four weeks was also

  2. Orbiter entry trajectory corridors: 32000 pound payload, 67.5 percent center of gravity. [glide path data compilation

    NASA Technical Reports Server (NTRS)

    Treybig, J. H.

    1975-01-01

    Thermal and equilibrium glide boundaries were used to analyze and/or design shuttle orbiter entry trajectories. Plots are presented of orbiter thermal and equilibrium glide boundaries in the drag/mass-relative velocity dynamic pressure-relative velocity, and altitude-relative velocity planes for an orbiter having a 32,000 pound payload and a 67.5% center of gravity location. These boundaries were defined for control points 1 through 4 of the shuttle orbiter for 40 deg-30 deg and 38 deg-28 deg ramped angle of attack entry profiles and 40 deg, 38 deg, 35 deg, 30 deg, 28 deg, and 25 deg constant angle of attack entry profiles each at 20 deg, 15 deg, and 10 deg constant body flap settings.

  3. [Successful tracheal intubation using the GlideScope AVL in a pediatric patient with Pierre Robin syndrome].

    PubMed

    Iwai, Hidetaka; Mouri, Hideyuki; Hirabayashi, Yoshihiro; Takeuchi, Mamoru

    2014-06-01

    We report a successful use of GlideScope AVL in a pediatric patient with Pierre Robin syndrome. A 36-day-old boy weighing 2.8 kg with Pierre Robin syndrome presented for tracheostomy after several weeks of trial airway management in prone position, who had failed to relieve his obstructive apnea. The Pentax-AWS videolaryngoscope equipped with the neonate Introck could not visualize his glottic opening. The GlideScope AVL single-use video laryngoscope equipping the #1 stat captured the view of the vocal cords. A tracheal tube (2.5 mm ID) with 90 degrees angled stylet, however, did not advance into the glottic opening, colliding with the anterior wall of the larynx and/or the laryngeal ventricle. Bending the tip of the stylet in a direction opposite to the inherent memory of the tube facilitated the placement of the tube into the trachea PMID:24979857

  4. The Screw-Like Movement of a Gliding Bacterium Is Powered by Spiral Motion of Cell-Surface Adhesins.

    PubMed

    Shrivastava, Abhishek; Roland, Thibault; Berg, Howard C

    2016-09-01

    Flavobacterium johnsoniae, a rod-shaped bacterium, glides over surfaces at speeds of ∼2 μm/s. The propulsion of a cell-surface adhesin, SprB, is known to enable gliding. We used cephalexin to generate elongated cells with irregular shapes and followed their displacement in three dimensions. These cells rolled about their long axes as they moved forward, following a right-handed trajectory. We coated gold nanoparticles with an SprB antibody and tracked them in three dimensions in an evanescent field where the nanoparticles appeared brighter when they were closer to the glass. The nanoparticles followed a right-handed spiral trajectory on the surface of the cell. Thus, if SprB were to adhere to the glass rather than to a nanoparticle, the cell would move forward along a right-handed trajectory, as observed, but in a direction opposite to that of the nanoparticle. PMID:27602728

  5. Effects of vaccination with F-strain Mycoplasma gallisepticum on egg production and quality parameters of commercial layer hens previously vaccinated with 6/85-strain Mycoplasma gallisepticum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An experiment was conducted to determine the effect of overlaying (revaccinating) F strain Mycoplasma gallisepticum (MG) at 22 or 45 weeks of age on commercial leghorn hens previously vaccinated with 6/85 strain MG at 10 weeks of age. The treatment groups include unvaccinated hens (group 1), hens r...

  6. Differentiation of Mycoplasma gallisepticum vaccine strains ts-11 and 6/85 from commonly used Mycoplasma gallisepticum challenge strains by PCR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycoplasma gallisepticum (MG) is an important avian pathogen causing significant economic losses within the poultry layer industry. In an effort to develop tools to aid in MG research and diagnostics, we have compared available sequences of the attenuated MG vaccine strain ts-11 to those of commonl...

  7. Effects of time specific F-strain Mycoplasma gallisepticum inoculation overlays on pre-lay ts11-strain Mycoplasma gallisepticum inoculation on performance characteristics of commercial laying hens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycoplasma bacteria are virtually ubiquitous in layer chicken flocks and M. gallisepticum is the species of greatest concern to commercial egg producers. Live M. gallisepticum vaccines were initially approved by the USDA for use in commercial layers in 1988 to help control M. gallisepticum outbreaks...

  8. Plant Viruses and Mycoplasmas. Proceedings of a Workshop on Plant Viruses and Mycoplasmas Held at the Botany Department, National University of Singapore, Singapore, May 24-27, 1983.

    ERIC Educational Resources Information Center

    Lim, G., Ed.; And Others

    A workshop on plant viruses and mycoplasmas brought together scientists and researchers working on these microorganisms in the countries of eastern Asia, and enabled them to discuss their studies, to exchange ideas, and to become familiar with their counterparts These proceedings of the workshop contain papers which include country reports,…

  9. Development and clinical application of an InvaderPlus® assay for the detection of genital mycoplasmas.

    PubMed

    Takanashi, Masaki; Ito, Shin; Kaneto, Hiroyuki; Tanahashi, Yoshikatsu; Kitanohara, Masataka; Yanagihara, Akira; Nakazima, Haruhiko; Yasuda, Mitsuru

    2015-07-01

    We developed a PCR-based assay involving Invader® technology for detection of the genital mycoplasmas of Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum. We compared its performance with that of a PCR-microtiter plate hybridization assay, which we developed previously, in detecting genital mycoplasmas in first-voided urine (FVU) specimens from men with non-gonococcal urethritis. The tests targeting each of the genital mycoplasmas were specific for the respective species and could detect as few as 10 copies of the plasmids containing the target genes of each of the genital mycoplasmas per reaction. The assay using the InvaderPlus® method (InvaderPlus® assay) showed very similar performance to that of the PCR-microtiter plate hybridization assay for detecting the genital mycoplasmas in the FVU specimens. In addition, the PCR and endonuclease reaction in the InvaderPlus® assay were carried out simultaneously in one procedure, thus simplifying the assay, leading to time- and labor-savings and a decrease in the risk of specimen contamination. The InvaderPlus® assay could be useful in diagnosing genitourinary tract infections caused by the genital mycoplasmas. PMID:25892209

  10. Stabilization of live Mycoplasma gallisepticum vaccines during vaccination with second generation Spray-Vac® vaccine stabilizer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dilutions and application of live Mycoplasma gallisepticum vaccines without the use of vaccine stabilizing compounds may lead to significant loss of vaccine viability and loss of vaccine efficacy. Vaccine viability may decreases due to osmotic lysis of the mycoplasma as well as the presence of chlo...

  11. Characterization of Mutations in DNA Gyrase and Topoisomerase IV Involved in Quinolone Resistance of Mycoplasma gallisepticum Mutants Obtained In Vitro

    PubMed Central

    Reinhardt, A. K.; Bébéar, C. M.; Kobisch, M.; Kempf, I.; Gautier-Bouchardon, A. V.

    2002-01-01

    Mycoplasma gallisepticum enrofloxacin-resistant mutants were generated by stepwise selection in increasing concentrations of enrofloxacin. Alterations were found in the quinolone resistance-determining regions of the four target genes encoding DNA gyrase and topoisomerase IV from these mutants. This is the first description of such mutations in an animal mycoplasma species. PMID:11796386

  12. Phenotypic characterization of Mycoplasma synoviae induced changes in the metabolic and sensitivity profile of in vitro infected chicken chondrocytes.

    PubMed

    Dušanić, Daliborka; Benčina, Dušan; Narat, Mojca; Oven, Irena

    2014-01-01

    In infectious synovitis caused by Mycoplasma synoviae chicken chondrocytes (CCH) may come into direct contact with these bacteria that are also capable of invading CCH in vitro. In this study, phenotype microarrays were used to evaluate the influence of Mycoplasma synoviae on the global metabolic activity of CCH. Therefore, CCH were cultured in the presence of 504 individual compounds, spotted in wells of 11 phenotype microarrays for eukaryotic cells, and exposed to Mycoplasma synoviae membranes or viable Mycoplasma synoviae. Metabolic activity and sensitivity of normal cells versus infected cells were evaluated. Metabolic profiles of CCH treated with viable Mycoplasma synoviae or its membranes were significantly different from those of CCH alone. CCH treated with Mycoplasma synoviae membranes were able to use 48 carbon/nitrogen sources not used by CCH alone. Treatment also influenced ion uptake in CCH and intensified the sensitivity to 13 hormones, 5 immune mediators, and 29 cytotoxic chemicals. CCH were even more sensitive to hormones/immune mediators when exposed to viable Mycoplasma synoviae. Our results indicate that exposure to Mycoplasma synoviae or its membranes induces a wide range of metabolic and sensitivity modifications in CCH that can contribute to pathological processes in the development of infectious synovitis. PMID:25243158

  13. Mycoplasma hyorhinis-Contaminated Cell Lines Activate Primary Innate Immune Cells via a Protease-Sensitive Factor

    PubMed Central

    Heidegger, Simon; Jarosch, Alexander; Schmickl, Martina; Endres, Stefan; Bourquin, Carole; Hotz, Christian

    2015-01-01

    Mycoplasma are a frequent and occult contaminant of cell cultures, whereby these prokaryotic organisms can modify many aspects of cell physiology, rendering experiments that are conducted with such contaminated cells problematic. Chronic Mycoplasma contamination in human monocytic cells lines has been associated with suppressed Toll-like receptor (TLR) function. In contrast, we show here that components derived from a Mycoplasma hyorhinis-infected cell line can activate innate immunity in non-infected primary immune cells. Release of pro-inflammatory cytokines such as IL-6 by dendritic cells in response to Mycoplasma hyorhinis-infected cell components was critically dependent on the adapter protein MyD88 but only partially on TLR2. Unlike canonical TLR2 signaling that is triggered in response to the detection of Mycoplasma infection, innate immune activation by components of Mycoplasma-infected cells was inhibited by chloroquine treatment and sensitive to protease treatment. We further show that in plasmacytoid dendritic cells, soluble factors from Mycoplasma hyorhinis-infected cells induce the production of large amounts of IFN-α. We conclude that Mycoplasma hyorhinis-infected cell lines release protein factors that can potently activate co-cultured innate immune cells via a previously unrecognized mechanism, thus limiting the validity of such co-culture experiments. PMID:26565413

  14. Mycoplasma hyorhinis-Contaminated Cell Lines Activate Primary Innate Immune Cells via a Protease-Sensitive Factor.

    PubMed

    Heidegger, Simon; Jarosch, Alexander; Schmickl, Martina; Endres, Stefan; Bourquin, Carole; Hotz, Christian

    2015-01-01

    Mycoplasma are a frequent and occult contaminant of cell cultures, whereby these prokaryotic organisms can modify many aspects of cell physiology, rendering experiments that are conducted with such contaminated cells problematic. Chronic Mycoplasma contamination in human monocytic cells lines has been associated with suppressed Toll-like receptor (TLR) function. In contrast, we show here that components derived from a Mycoplasma hyorhinis-infected cell line can activate innate immunity in non-infected primary immune cells. Release of pro-inflammatory cytokines such as IL-6 by dendritic cells in response to Mycoplasma hyorhinis-infected cell components was critically dependent on the adapter protein MyD88 but only partially on TLR2. Unlike canonical TLR2 signaling that is triggered in response to the detection of Mycoplasma infection, innate immune activation by components of Mycoplasma-infected cells was inhibited by chloroquine treatment and sensitive to protease treatment. We further show that in plasmacytoid dendritic cells, soluble factors from Mycoplasma hyorhinis-infected cells induce the production of large amounts of IFN-α. We conclude that Mycoplasma hyorhinis-infected cell lines release protein factors that can potently activate co-cultured innate immune cells via a previously unrecognized mechanism, thus limiting the validity of such co-culture experiments. PMID:26565413

  15. Incidence and antibiotic susceptibility of Mycoplasma hominis and Ureaplasma urealyticum isolated in Brescia, Italy, over 7 years.

    PubMed

    De Francesco, Maria Antonia; Caracciolo, Sonia; Bonfanti, Carlo; Manca, Nino

    2013-08-01

    The prevalence and antimicrobial susceptibility of Ureaplasma urealyticum and Mycoplasma hominis collected during 2004-2011 were determined. A total of 9956 individuals was analyzed. Identification was performed by use of the mycoplasma IST-2 kit. Antimicrobial susceptibility against doxycycline, josamycin, ofloxacin, erythromycin, tetracycline, ciprofloxacin, azithromycin, clarithromycin, and pristinamycin was also tested by use of this commercial kit. Our results show a prevalence of 1856 positive patients for genital mycoplasmas (18.6 %). Among positive cultures, 89 and 1.1 % of isolates were Ureaplasma urealyticum and Mycoplasma hominis, respectively. For 9.8 % of isolates both urogenital mycoplasmas were grown. Doxycycline was the most active tetracycline for mycoplasma infections, and this is still the drug of first choice. Among macrolides, josamycin and clarithromycin are the most active agents against ureaplasmas; josamycin is also active against mycoplasmas and is an alternative to tetracyclines and erythromycin for mixed infections, especially for pregnant women and neonates. Fluoroquinolones had low efficacy against urogenital mycoplasmas. For Ureaplasma urealyticum, cross-resistance was found between erythromycin and macrolides (except josamycin) (40-80 %) and between erythromycin and ciprofloxacin (79 %). Antibiotic resistance over the test period did not vary significantly. Because of geographical differences among antibiotic resistance, local in-vitro susceptibility testing is recommended to avoid failure of therapy. PMID:23192735

  16. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... for inoculation with contaminated tissues should be serologically negative by the serum plate... in four times their volume of Mycoplasma Broth Medium (Frey), (see § 147.15(f)). Suspensions may be... serum plate antibodies for the mycoplasma for which the donor birds were tested, regardless of HI...

  17. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... for inoculation with contaminated tissues should be serologically negative by the serum plate... in four times their volume of Mycoplasma Broth Medium (Frey), (see § 147.15(f)). Suspensions may be... serum plate antibodies for the mycoplasma for which the donor birds were tested, regardless of HI...

  18. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... for inoculation with contaminated tissues should be serologically negative by the serum plate... in four times their volume of Mycoplasma Broth Medium (Frey), (see § 147.15(f)). Suspensions may be... serum plate antibodies for the mycoplasma for which the donor birds were tested, regardless of HI...

  19. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... for inoculation with contaminated tissues should be serologically negative by the serum plate... in four times their volume of Mycoplasma Broth Medium (Frey), (see § 147.15(f)). Suspensions may be... serum plate antibodies for the mycoplasma for which the donor birds were tested, regardless of HI...

  20. Complete Genome Sequence of Mycoplasma arginini Strain HAZ 145_1 from Bovine Mastitic Milk in Japan.

    PubMed

    Hata, Eiji

    2015-01-01

    Mycoplasma arginini is a species sometimes isolated from bovine specimens, mastitic milk, etc. Its pathogenicity against cows, however, is unspecific, unlike other bovine mycoplasmas. Its whole-genome sequence is needed to comprehend its real image. We present here the 678,592-bp complete genome sequence of M. arginini strain HAZ 145_1. PMID:25883285

  1. Novel Features of the Polysaccharide-Digesting Gliding Bacterium Flavobacterium johnsoniae as Revealed by Genome Sequence Analysis▿ †

    PubMed Central

    McBride, Mark J.; Xie, Gary; Martens, Eric C.; Lapidus, Alla; Henrissat, Bernard; Rhodes, Ryan G.; Goltsman, Eugene; Wang, Wei; Xu, Jian; Hunnicutt, David W.; Staroscik, Andrew M.; Hoover, Timothy R.; Cheng, Yi-Qiang; Stein, Jennifer L.

    2009-01-01

    The 6.10-Mb genome sequence of the aerobic chitin-digesting gliding bacterium Flavobacterium johnsoniae (phylum Bacteroidetes) is presented. F. johnsoniae is a model organism for studies of bacteroidete gliding motility, gene regulation, and biochemistry. The mechanism of F. johnsoniae gliding is novel, and genome analysis confirms that it does not involve well-studied motility organelles, such as flagella or type IV pili. The motility machinery is composed of Gld proteins in the cell envelope that are thought to comprise the “motor” and SprB, which is thought to function as a cell surface adhesin that is propelled by the motor. Analysis of the genome identified genes related to sprB that may encode alternative adhesins used for movement over different surfaces. Comparative genome analysis revealed that some of the gld and spr genes are found in nongliding bacteroidetes and may encode components of a novel protein secretion system. F. johnsoniae digests proteins, and 125 predicted peptidases were identified. F. johnsoniae also digests numerous polysaccharides, and 138 glycoside hydrolases, 9 polysaccharide lyases, and 17 carbohydrate esterases were predicted. The unexpected ability of F. johnsoniae to digest hemicelluloses, such as xylans, mannans, and xyloglucans, was predicted based on the genome analysis and confirmed experimentally. Numerous predicted cell surface proteins related to Bacteroides thetaiotaomicron SusC and SusD, which are likely involved in binding of oligosaccharides and transport across the outer membrane, were also identified. Genes required for synthesis of the novel outer membrane flexirubin pigments were identified by a combination of genome analysis and genetic experiments. Genes predicted to encode components of a multienzyme nonribosomal peptide synthetase were identified, as were novel aspects of gene regulation. The availability of techniques for genetic manipulation allows rapid exploration of the features identified for the

  2. Take-off and landing forces and the evolution of controlled gliding in northern flying squirrels Glaucomys sabrinus.

    PubMed

    Paskins, Keith E; Bowyer, Adrian; Megill, William M; Scheibe, John S

    2007-04-01

    Flying squirrels are well known for their ability to glide between trees at the top of a forest canopy. We present experimental performance and behavioural evidence that flight in flying squirrels may have evolved out of a need to control landing forces. Northern flying squirrels were filmed jumping from a horizontal branch to a much larger vertical pole. These were both slightly compliant (less than 1.9 mm N(-1)), and instrumented using strain gauges so that forces could be measured. Take-off and landing forces were both positively correlated with horizontal range between 0.5 and 2.5 m (r=0.355 and r=0.811, respectively, P<0.05), but not significantly different to each other at each range tested. Take-off forces ranged from 1 to 10 bodyweights, and landing forces were between 3 and 10 bodyweights. Glide angles increased rapidly with horizontal range, approaching 45 degrees at 3 m, above which they gradually decreased, suggesting that northern flying squirrels are optimised for long distance travel. We show that northern flying squirrels initiate full gliding posture at ranges of less than 1 m, without landing any higher than an equivalent ballistic projectile. However, this gliding posture enables them to pitch upwards, potentially stalling the wing, and spreads the landing reaction force over all four extended limbs. At steeper approach angles of close to 45 degrees , flying squirrels were unable to pitch up sufficiently and landed forelimbs first, consequently sustaining higher impact forces. We investigate four hypotheses to explain the origin of flight in these animals and conclude that the need to reduce landing impact forces was most likely to have stimulated the development of aerial control in flying squirrels. PMID:17401124

  3. Problems Involved in an Emergency Method of Guiding a Gliding Vehicle from High Altitudes to a High Key Position

    NASA Technical Reports Server (NTRS)

    Jewel, Joseph W., Jr.; Whitten, James B.

    1960-01-01

    An investigation has been conducted to determine the problems involved in an emergency method of guiding a gliding vehicle from high altitudes to a high key position (initial position) above a landing field. A jet airplane in a simulated flameout condition, conventional ground-tracking radar, and a scaled wire for guidance programming on the radar plotting board were used in the tests. Starting test altitudes varied from 30,000 feet to 46,500 feet, and starting positions ranged 8.4 to 67 nautical miles from the high key. Specified altitudes of the high key were 12,000, 10,000 or 4,000 feet. Lift-drag ratios of the aircraft of either 17, 16, or 6 were held constant during any given flight; however, for a few flights the lift-drag ratio was varied from 11 to 6. Indicated airspeeds were held constant at either 160 or 250 knots. Results from these tests indicate that a gliding vehicle having a lift-drag ratio of 16 and an indicated approach speed of 160 knots can be guided to within 800 feet vertically and 2,400 feet laterally of a high key position. When the lift-drag ratio of the vehicle is reduced to 6 and the indicated approach speed is raised to 250 knots, the radar controller was able to guide the vehicle to within 2,400 feet vertically and au feet laterally of the high key. It was also found that radar stations which give only azimuth-distance information could control the glide path of a gliding vehicle as well as stations that receive azimuth-distance-altitude information, provided that altitude information is supplied by the pilot.

  4. A Middle Triassic thoracopterid from China highlights the evolutionary origin of overwater gliding in early ray-finned fishes

    PubMed Central

    Xu, Guang-Hui; Zhao, Li-Jun; Shen, Chen-Chen

    2015-01-01

    Gliding adaptations in thoracopterid flying fishes represent a remarkable case of convergent evolution of overwater gliding strategy with modern exocoetid flying fishes, but the evolutionary origin of this strategy was poorly known in the thoracopterids because of lack of transitional forms. Until recently, all thoracopterids, from the Late Triassic of Austria and Italy and the Middle Triassic of South China, were highly specialized ‘four-winged’ gliders in having wing-like paired fins and an asymmetrical caudal fin with the lower caudal lobe notably larger than the upper lobe. Here, we show that the new genus Wushaichthys and the previously alleged ‘peltopleurid’ Peripeltopleurus, from the Middle Triassic (Ladinian, 235–242 Ma) of South China and near the Ladinian/Anisian boundary of southern Switzerland and northern Italy, respectively, represent the most primitive and oldest known thoracopterids. Wushaichthys, the most basal thoracopterid, shows certain derived features of this group in the skull. Peripeltopleurus shows a condition intermediate between Wushaichthys and Thoracopterus in having a slightly asymmetrical caudal fin but still lacking wing-like paired fins. Phylogenetic studies suggest that the evolution of overwater gliding of thoracopterids was gradual in nature; a four-stage adaption following the ‘cranial specialization–asymmetrical caudal fin–enlarged paired fins–scale reduction’ sequence has been recognized in thoracopterid evolution. Moreover, Wushaichthys and Peripeltopleurus bear hooklets on the anal fin of supposed males, resembling those of modern viviparious teleosts. Early thoracopterids probably had evolved a live-bearing reproductive strategy. PMID:25568155

  5. Parker Flex-It stylet is as effective as GlideRite Rigid stylet for orotracheal intubation by Glidescope

    PubMed Central

    Sheta, Saad A.; Abdelhalim, Ashraf A.; ElZoughari, Ismail A.; AlZahrani, Tariq A.; Al-Saeed, Abdulhamid H.

    2015-01-01

    Objectives: To evaluate Parker Flex-It stylet as an alternative to GlideRite Rigid stylet to aid tracheal intubation with the Glidescope. Methods: This prospective randomized trial was conducted at King Abdulaziz University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia between May and December 2014. Sixty American Society of Anesthesiologists I-II patients were randomly assigned to one of 2 equal groups receiving intubation by Glidescope using either GlideRite Rigid stylet (Group GS) or Parker Flex-It stylet (Group PS). The total intubation time, ease of intubation, incidences of successful intubation at first attempt, number of intubation attempts, use of optimization maneuvers, and possible complications were recorded. Results: No significant differences between both groups regarding the total intubation time (p=0.08) was observed. Intubation was significantly easier in group PS compared with group GS as measured by visual analogue scale (p=0.001) with no significant differences between the groups regarding the rate of successful tracheal intubation from first attempt (p=0.524). However, the number of attempts at intubation and usage of external laryngeal manipulation were similar in both groups (p>0.05). The incidence of sore throat, dysphagia, hoarseness, and trauma were significantly higher in group GS (p<0.05). Conclusion: Parker Flex-It stylet is as effective as GlideRite Rigid stylet when used by experienced operators in patients with normal airways using Glidescope; however, it is easier and less traumatic. PMID:26620987

  6. CR TKA UHMWPE wear tested after artificial aging of the vitamin E treated gliding component by simulating daily patient activities.

    PubMed

    Schwiesau, Jens; Fritz, Bernhard; Kutzner, Ines; Bergmann, Georg; Grupp, Thomas M

    2014-01-01

    The wear behaviour of total knee arthroplasty (TKA) is dominated by two wear mechanisms: the abrasive wear and the delamination of the gliding components, where the second is strongly linked to aging processes and stress concentration in the material. The addition of vitamin E to the bulk material is a potential way to reduce the aging processes. This study evaluates the wear behaviour and delamination susceptibility of the gliding components of a vitamin E blended, ultra-high molecular weight polyethylene (UHMWPE) cruciate retaining (CR) total knee arthroplasty. Daily activities such as level walking, ascending and descending stairs, bending of the knee, and sitting and rising from a chair were simulated with a data set received from an instrumented knee prosthesis. After 5 million test cycles no structural failure of the gliding components was observed. The wear rate was with 5.62 ± 0.53 mg/million cycles falling within the limit of previous reports for established wear test methods. PMID:25506594

  7. CR TKA UHMWPE Wear Tested after Artificial Aging of the Vitamin E Treated Gliding Component by Simulating Daily Patient Activities

    PubMed Central

    Schwiesau, Jens; Fritz, Bernhard; Kutzner, Ines; Bergmann, Georg; Grupp, Thomas M.

    2014-01-01

    The wear behaviour of total knee arthroplasty (TKA) is dominated by two wear mechanisms: the abrasive wear and the delamination of the gliding components, where the second is strongly linked to aging processes and stress concentration in the material. The addition of vitamin E to the bulk material is a potential way to reduce the aging processes. This study evaluates the wear behaviour and delamination susceptibility of the gliding components of a vitamin E blended, ultra-high molecular weight polyethylene (UHMWPE) cruciate retaining (CR) total knee arthroplasty. Daily activities such as level walking, ascending and descending stairs, bending of the knee, and sitting and rising from a chair were simulated with a data set received from an instrumented knee prosthesis. After 5 million test cycles no structural failure of the gliding components was observed. The wear rate was with 5.62 ± 0.53 mg/million cycles falling within the limit of previous reports for established wear test methods. PMID:25506594

  8. A Middle Triassic thoracopterid from China highlights the evolutionary origin of overwater gliding in early ray-finned fishes.

    PubMed

    Xu, Guang-Hui; Zhao, Li-Jun; Shen, Chen-Chen

    2015-01-01

    Gliding adaptations in thoracopterid flying fishes represent a remarkable case of convergent evolution of overwater gliding strategy with modern exocoetid flying fishes, but the evolutionary origin of this strategy was poorly known in the thoracopterids because of lack of transitional forms. Until recently, all thoracopterids, from the Late Triassic of Austria and Italy and the Middle Triassic of South China, were highly specialized 'four-winged' gliders in having wing-like paired fins and an asymmetrical caudal fin with the lower caudal lobe notably larger than the upper lobe. Here, we show that the new genus Wushaichthys and the previously alleged 'peltopleurid' Peripeltopleurus, from the Middle Triassic (Ladinian, 235-242 Ma) of South China and near the Ladinian/Anisian boundary of southern Switzerland and northern Italy, respectively, represent the most primitive and oldest known thoracopterids. Wushaichthys, the most basal thoracopterid, shows certain derived features of this group in the skull. Peripeltopleurus shows a condition intermediate between Wushaichthys and Thoracopterus in having a slightly asymmetrical caudal fin but still lacking wing-like paired fins. Phylogenetic studies suggest that the evolution of overwater gliding of thoracopterids was gradual in nature; a four-stage adaption following the 'cranial specialization-asymmetrical caudal fin-enlarged paired fins-scale reduction' sequence has been recognized in thoracopterid evolution. Moreover, Wushaichthys and Peripeltopleurus bear hooklets on the anal fin of supposed males, resembling those of modern viviparious teleosts. Early thoracopterids probably had evolved a live-bearing reproductive strategy. PMID:25568155

  9. Prevalence and Antibiotic Susceptibility of Mycoplasma hominis and Ureaplasma urealyticum in Pregnant Women.

    PubMed

    Lee, Min Young; Kim, Myeong Hee; Lee, Woo In; Kang, So Young; Jeon, You La

    2016-09-01

    Mycoplasma hominis (M. hominis) and Ureaplasma urealyticum (U. urealyticum) are important opportunistic pathogens that cause urogenital infections and complicate pregnancy. The aim of this study was to investigate the prevalence, effects on pregnancy outcomes, and antimicrobial susceptibilities of M. hominis and U. urealyticum. We tested vaginal swabs obtained from 1035 pregnant women for the presence of genital mycoplasmas between June 2009 and May 2014. The laboratory and clinical aspects of genital mycoplasmas infection were reviewed retrospectively, and the identification and antimicrobial susceptibility of genital mycoplasmas were determined using the Mycoplasma IST-2 kit. A total of 571 instances of M. hominis and/or U. urealyticum were detected. Of them, M. hominis was detected in two specimens, whereas U. urealyticum was detected in 472 specimens. The remaining 97 specimens were positive for both M. hominis and U. urealyticum. Preterm deliveries were frequently observed in cases of mixed infection of M. hominis and U. urealyticum, and instances of preterm premature rupture of membrane were often found in cases of U. urealyticum. The rates of non-susceptible isolates to erythromycin, empirical agents for pregnant women, showed increasing trends. In conclusion, the prevalence of M. hominis and/or U. urealyticum infections in pregnant women is high, and the resistance rate of antimicrobial agents tends to increase. Therefore, to maintain a safe pregnancy, it is important to identify the isolates and use appropriate empirical antibiotics immediately. PMID:27401661

  10. Molecular Methods for the Detection of Mycoplasma and Ureaplasma Infections in Humans

    PubMed Central

    Waites, Ken B.; Xiao, Li; Paralanov, Vanya; Viscardi, Rose M.; Glass, John I.

    2012-01-01

    Mycoplasma and Ureaplasma species are well-known human pathogens responsible for a broad array of inflammatory conditions involving the respiratory and urogenital tracts of neonates, children, and adults. Greater attention is being given to these organisms in diagnostic microbiology, largely as a result of improved methods for their laboratory detection, made possible by powerful molecular-based techniques that can be used for primary detection in clinical specimens. For slow-growing species, such as Mycoplasma pneumoniae and Mycoplasma genitalium, molecular-based detection is the only practical means for rapid microbiological diagnosis. Most molecular-based methods used for detection and characterization of conventional bacteria have been applied to these organisms. A complete genome sequence is available for one or more strains of all of the important human pathogens in the Mycoplasma and Ureaplasma genera. Information gained from genome analyses and improvements in efficiency of DNA sequencing are expected to significantly advance the field of molecular detection and genotyping during the next few years. This review provides a summary and critical review of methods suitable for detection and characterization of mycoplasmas and ureaplasmas of humans, with emphasis on molecular genotypic techniques. PMID:22819362

  11. Physical characteristics of gliding arc discharge plasma generated in a laval nozzle

    SciTech Connect

    Lu, S. Y.; Sun, X. M.; Li, X. D.; Yan, J. H.; Du, C. M.

    2012-07-15

    The dynamic behavior of gliding arc discharge generated in a Laval nozzle has been investigated by electrical diagnostics and a high-speed camera. The results show that the voltage waveform keeps the initial shape as the gas flow rate is small, while it becomes less stable with increasing flow rate. During the first half of a cycle, the voltage rises and after that it decreases. In nitrogen and oxygen, the break down voltage for the arc is between 3.3 and 5.5 kV, while it is between 3.3-7.5 kV in air. The waveform of current I remains almost stable; and for nitrogen and oxygen, the maximum value of current I is between 0.28 and 0.46 A. With increasing flow rate, the power consumption in air first increases and then decreases; it remains in the range of 110-217 W, and gradually increases in nitrogen and oxygen. The power consumption in oxygen is lower than that in nitrogen; the input of the energy density decreases with increasing flow rate for all the three gases. The development of the arc is tracked and recorded by a high-speed camera. The cycle is stable at 10 ms for flow rates up to 1 m{sup 3} h{sup -1}. At a higher flow rate, the cycle becomes unstable.

  12. The mercury resistance (mer) operon in a marine gliding flavobacterium, Tenacibaculum discolor 9A5.

    PubMed

    Allen, Rachel C; Tu, Yen-Kuei; Nevarez, Michael J; Bobbs, Alexander S; Friesen, Joseph W; Lorsch, Jon R; McCauley, John A; Voet, Judith G; Hamlett, Nancy V

    2013-01-01

    Genes conferring mercury resistance have been investigated in a variety of bacteria and archaea but not in bacteria of the phylum Bacteroidetes, despite their importance in many environments. We found, however, that a marine gliding Bacteroidetes species, Tenacibaculum discolor, was the predominant mercury-resistant bacterial taxon cultured from a salt marsh fertilized with mercury-contaminated sewage sludge. Here we report characterization of the mercuric reductase and the narrow-spectrum mercury resistance (mer) operon from one of these strains - T. discolor 9A5. This mer operon, which confers mercury resistance when cloned into Flavobacterium johnsoniae, encodes a novel mercury-responsive ArsR/SmtB family transcriptional regulator that appears to have evolved independently from other mercury-responsive regulators, a novel putative transport protein consisting of a fusion between the integral membrane Hg(II) transporter MerT and the periplasmic Hg(II)-binding protein MerP, an additional MerP protein, and a mercuric reductase that is phylogenetically distinct from other known mercuric reductases. PMID:22816663

  13. A computational study of the aerodynamic performance of a dragonfly wing section in gliding flight.

    PubMed

    Vargas, Abel; Mittal, Rajat; Dong, Haibo

    2008-06-01

    A comprehensive computational fluid-dynamics-based study of a pleated wing section based on the wing of Aeshna cyanea has been performed at ultra-low Reynolds numbers corresponding to the gliding flight of these dragonflies. In addition to the pleated wing, simulations have also been carried out for its smoothed counterpart (called the 'profiled' airfoil) and a flat plate in order to better understand the aerodynamic performance of the pleated wing. The simulations employ a sharp interface Cartesian-grid-based immersed boundary method, and a detailed critical assessment of the computed results was performed giving a high measure of confidence in the fidelity of the current simulations. The simulations demonstrate that the pleated airfoil produces comparable and at times higher lift than the profiled airfoil, with a drag comparable to that of its profiled counterpart. The higher lift and moderate drag associated with the pleated airfoil lead to an aerodynamic performance that is at least equivalent to and sometimes better than the profiled airfoil. The primary cause for the reduction in the overall drag of the pleated airfoil is the negative shear drag produced by the recirculation zones which form within the pleats. The current numerical simulations therefore clearly demonstrate that the pleated wing is an ingenious design of nature, which at times surpasses the aerodynamic performance of a more conventional smooth airfoil as well as that of a flat plate. For this reason, the pleated airfoil is an excellent candidate for a fixed wing micro-aerial vehicle design. PMID:18503106

  14. Nitrogen dioxide formation in the gliding arc discharge-assisted decomposition of volatile organic compounds.

    PubMed

    Bo, Zheng; Yan, Jianhua; Li, Xiaodong; Chi, Yong; Cen, Kefa

    2009-07-30

    To apply gliding arc discharge (GAD) plasma processing to volatile organic compounds (VOCs) emission control, the formation of NO(2) as an undesired byproduct needs to be addressed. Comparative results of effluent temperature and product concentrations between experiment and thermodynamic equilibrium calculation show that the NO(2) formation in dry air GAD is totally out of thermodynamic equilibrium. Meanwhile, obvious NO (A(2)Sigma+)) and N(2)(+) (B(2)Sigma(u)(+)) are detected as the major reactive species in the dry air GAD plasma region. These results suggest that the thermal (or Zeldovich) NO(x) formation mechanism is not significant in GAD system, while the energy level and the density of electrons in the plasma region will severely influence the NO(2) formation. The presence of 500 ppm VOCs in the feed gases shows a limiting influence on the NO(2) formation, which is in the order of aromatic hydrocarbon (C(6)H(6) and C(7)H(8))>straight-chain hydrocarbon (C(4)H(10) and C(6)H(14))>halogenated hydrocarbon (CCl(4)). The influences of VOCs chemical structure, supply voltage, feed gas humidity, and reactor geometry on NO(2) formation are investigated, and the results correspond to above mechanism analysis. Based on the above, the possible pathways of the inhibition of NO(2) formation in GAD-assisted VOCs decomposition process are discussed. PMID:19153003

  15. Removal of gaseous HxCBz by gliding arc plasma in combination with a catalyst.

    PubMed

    Ren, Yong; Li, Xiaodong; Ji, Shasha; Lu, Shengyong; Buekens, Alfons; Yan, Jianhua

    2014-12-01

    Hexachlorobenzene (HxCBz) owns the chemical structure of one benzene ring and six H atoms substituted by Cl atoms and it is a persistent organic pollutant present in flue gas from municipal solid waste incineration as an important precursor of dioxins. Its removal was studied using gliding arc plasma treatment, coupled downstream with a V2O5–WO3–TiO2 catalyst. Several parameters (input voltage, O2 concentration, catalytic temperature and catalyst position) all influenced its removal efficiency (RE). Optimal parameter settings were tentatively determined, i.e., an input voltage of 15 kV, the temperature of the catalyst (250 °C), and the O2 concentration (30 vol% O2) tested at a single, fixed concentration of gaseous HxCBz (71.6 ng Nm−3). A maximum RE of 76 ± 3% HxCBz was attained, with the plasma and coupled catalyst combined. Two destruction pathways, incorporating dechlorination and oxidation reactions, were recognised, both based on the detection of end- and intermediate products as well as of active species produced by the plasma. These end- and intermediate products included: low chlorinated polychlorobenzenes (mainly 1,2,4-Trichlorobenzene) as well as hydrocarbons (mainly C2H6), HCOOH, CH4, CO, CO2, etc. PMID:25461941

  16. Dislocation gliding and cross-hatch morphology formation in AIII-BV epitaxial heterostructures

    SciTech Connect

    Kovalskiy, V. A. Vergeles, P. S.; Eremenko, V. G.; Fokin, D. A.

    2014-12-08

    An approach for understanding the origin of cross-hatch pattern (CHP) on the surface of lattice mismatched GaMnAs/InGaAs samples grown on GaAs (001) substrates is developed. It is argued that the motion of threading dislocations in the (111) slip planes during the relaxation of InGaAs buffer layer is more complicated process and its features are similar to the ones of dislocation half-loops gliding in plastically deformed crystals. The heterostructures were characterized by atomic force microscopy and electron beam induced current (EBIC). Detailed EBIC experiments revealed contrast features, which cannot be accounted for by the electrical activity of misfit dislocations at the buffer/substrate interface. We attribute these features to specific extended defects (EDs) generated by moving threading dislocations in the partially relaxed InGaAs layers. We believe that the core topology, surface reconstruction, and elastic strains from these EDs accommodated in slip planes play an important role in the CHP formation. The study of such electrically active EDs will allow further understanding of degradation and changes in characteristics of quantum devices based on strained heterostructures.

  17. On-chip microtubule gliding assay for parallel measurement of tau protein species.

    PubMed

    Subramaniyan Parimalam, Subhathirai; Tarhan, Mehmet C; Karsten, Stanislav L; Fujita, Hiroyuki; Shintaku, Hirofumi; Kotera, Hidetoshi; Yokokawa, Ryuji

    2016-04-26

    Tau protein is a well-established biomarker for a group of neurodegenerative diseases collectively called tauopathies. So far, clinically relevant detection of tau species in cerebrospinal fluid (CSF) cannot be achieved without immunological methods. Recently, it was shown that different tau isoforms including the ones carrying various types of mutations affect microtubule (MT)-kinesin binding and velocity in an isoform specific manner. Here, based on these observations, we developed a microfluidic device to analyze tau mutations, isoforms and their ratios. The assay device consists of three regions: a MT reservoir which captures MTs from a solution to a kinesin-coated surface, a microchannel which guides gliding MTs, and an arrowhead-shaped collector which concentrates MTs. Tau-bound fluorescently labeled MTs (tau-MTs) were assayed, and the increase in fluorescence intensity (FI) corresponding to the total number of MTs accumulated was measured at the collector. We show that our device is capable of differentiating 3R and 4R tau isoform ratios and effects of point mutations within 5 minutes. Furthermore, radially oriented collector regions enable simultaneous FI measurements for six independent assays. Performing parallel assays in the proposed device with minimal image processing provides a cost-efficient, easy-to-use and fast tau detection platform. PMID:27056640

  18. Leaping shampoo glides on a 500-nm-thick lubricating air layer

    NASA Astrophysics Data System (ADS)

    Li, Erqiang; Lee, Sanghyun; Marston, Jeremy; Bonito, Andrea; Thoroddsen, Sigurdur

    2013-11-01

    When a stream of shampoo is fed onto a pool in one's hand, a jet can leap sideways or rebound from the liquid surface in an intriguing phenomenon known as the Kaye effect. Earlier studies have debated whether non-Newtonian effects are the underlying cause of this phenomenon, making the jet glide on top of a shear-thinning liquid layer, or whether an entrained air layer is responsible. Herein we show unambiguously that the jet slides on a lubricating air layer [Lee et al., Phys. Rev. E 87, 061001 (2013)]. We identify this layer by looking through the pool liquid and observing its rupture into fine micro-bubbles. The resulting micro-bubble sizes suggest that the thickness of this air layer is around 500 nm. This thickness estimate is also supported by the tangential deceleration of the jet during the rebounding, with the shear stress within the thin air layer sufficient for the observed deceleration. Particle tracking within the jet shows uniform velocity, with no pronounced shear, which would be required for shear-thinning effects. The role of the surfactant may primarily be to stabilize the air film.

  19. Genome sequence of the filamentous, gliding Thiothrix nivea neotype strain (JP2T)

    PubMed Central

    Lapidus, Alla; Nolan, Matt; Lucas, Susan; Glavina Del Rio, Tijana; Tice, Hope; Cheng, Jan-Fang; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne; Pitluck, Sam; Liolios, Konstantinos; Pagani, Ioanna; Ivanova, Natalia; Huntemann, Marcel; Mavromatis, Konstantinos; Mikhailova, Natalia; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Land, Miriam; Brambilla, Evelyne-Marie; Rohde, Manfred; Abt, Birte; Verbarg, Susanne; Göker, Markus; Bristow, James; Eisen, Jonathan A.; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C.; Klenk, Hans-Peter; Woyke, Tanja

    2011-01-01

    Thiothrix nivea (Rabenhorst 1865) Winogradsky 1888 (Approved Lists 1980) emend. Larkin and Shinabarger 1983 is the type species of the genus Thiothrix in the family Thiotrichaceae. The species is of interest not only because of its isolated location in the yet to be genomically characterized region of the tree of life, but also because of its life-style with gliding gonidia, the multilayer sheath, rosettes, and the embedded sulfur granules. Strain JP2T is the neotype strain of the species which was first observed by Rabenhorst in 1865 and later reclassified by Winogradsky in 1888 into the then novel genus Thiothrix. This is the first completed (improved-high-quality-draft) genome sequence to be published of a member of the family Thiotrichaceae. The genome in its current assembly consists of 15 contigs in four scaffolds with a total of 4,691,711 bp bearing 4,542 protein-coding and 52 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. PMID:22675589

  20. Dislocation gliding and cross-hatch morphology formation in AIII-BV epitaxial heterostructures

    NASA Astrophysics Data System (ADS)

    Kovalskiy, V. A.; Vergeles, P. S.; Eremenko, V. G.; Fokin, D. A.; Dorokhin, M. V.; Danilov, Yu. A.; Zvonkov, B. N.

    2014-12-01

    An approach for understanding the origin of cross-hatch pattern (CHP) on the surface of lattice mismatched GaMnAs/InGaAs samples grown on GaAs (001) substrates is developed. It is argued that the motion of threading dislocations in the {111} slip planes during the relaxation of InGaAs buffer layer is more complicated process and its features are similar to the ones of dislocation half-loops gliding in plastically deformed crystals. The heterostructures were characterized by atomic force microscopy and electron beam induced current (EBIC). Detailed EBIC experiments revealed contrast features, which cannot be accounted for by the electrical activity of misfit dislocations at the buffer/substrate interface. We attribute these features to specific extended defects (EDs) generated by moving threading dislocations in the partially relaxed InGaAs layers. We believe that the core topology, surface reconstruction, and elastic strains from these EDs accommodated in slip planes play an important role in the CHP formation. The study of such electrically active EDs will allow further understanding of degradation and changes in characteristics of quantum devices based on strained heterostructures.

  1. Kinesin force generation measured using a centrifuge microscope sperm-gliding motility assay.

    PubMed Central

    Hall, K; Cole, D; Yeh, Y; Baskin, R J

    1996-01-01

    To measure force generation and characterize the relationship between force and velocity in kinesin-driven motility we have developed a centrifuge microscope sperm-gliding motility assay. The average (extrapolated) value of maximum isometric force at low kinesin density was 0.90 +/- 0.14 pN. Furthermore, in the experiments at low kinesin density, sperm pulled off before stall at forces between 0.40 and 0.75 pN. To further characterize our kinesin-demembranated sperm assay we estimated maximum isometric force using a laser trap-based assay. At low kinesin density, 4.34 +/- 1.5 pN was the maximum force. Using values of axoneme stiffness available from other studies, we concluded that, in our centrifuge microscope-based assay, a sperm axoneme functions as a lever arm, magnifying the centrifugal force and leading to pull-off before stall. In addition, drag of the distal portion of the axoneme is increased by the centrifugal force (because the axoneme is rotated into closer proximity to the glass surface) and represents an additional force that the kinesin motor must overcome. Images FIGURE 1 FIGURE 9 FIGURE 10 PMID:8968616

  2. Impulse Three Phase Power Supply Used for a Gliding Plasma Discharge

    NASA Astrophysics Data System (ADS)

    Salazar-Torres, J. A.; Pacheco-Sotelo, J.; Valdivia-Barrientos, R.; Pacheco-Pacheco, M.; Ramos-Flores, F.; Soria-Arguello, G.; Ibañez-Olvera, M.

    2015-03-01

    Power sources used for generating plasma have different configurations depending on the particular application; the aim here comprises the maximum energy transfer to the plasma discharge reaching. This work shows the performance and versatility of a simple impulse phase power source, applied to gliding arc plasma discharge. It is capable of changing the operating frequency from 5 kHz up to 150 kHz and the duty cycle from 1% to 33% in all three phases, each one connected to three divergent tungsten electrodes. This allows a soft start plasma ignition until the full load is reached. This converter uses a sequential logic circuits composed by flip-flops, gates drivers, IGBT's and high voltage ferrite transformers. These features facilitate the maximum energy transfer to the plasma without using more complex electronic structures. The effect of frequency, duty cycle, voltage and current wave form signals is here described. This power supply has the adaptability to work whit different type of gas such as Argon, Helium, Air and Nitrogen. A Matlab Simulink simulation validates the experimental results. The main features and advantages of this configuration are also defined.

  3. Physical characteristics of gliding arc discharge plasma generated in a laval nozzle

    NASA Astrophysics Data System (ADS)

    Lu, S. Y.; Sun, X. M.; Li, X. D.; Yan, J. H.; Du, C. M.

    2012-07-01

    The dynamic behavior of gliding arc discharge generated in a Laval nozzle has been investigated by electrical diagnostics and a high-speed camera. The results show that the voltage waveform keeps the initial shape as the gas flow rate is small, while it becomes less stable with increasing flow rate. During the first half of a cycle, the voltage rises and after that it decreases. In nitrogen and oxygen, the break down voltage for the arc is between 3.3 and 5.5 kV, while it is between 3.3-7.5 kV in air. The waveform of current I remains almost stable; and for nitrogen and oxygen, the maximum value of current I is between 0.28 and 0.46 A. With increasing flow rate, the power consumption in air first increases and then decreases; it remains in the range of 110-217 W, and gradually increases in nitrogen and oxygen. The power consumption in oxygen is lower than that in nitrogen; the input of the energy density decreases with increasing flow rate for all the three gases. The development of the arc is tracked and recorded by a high-speed camera. The cycle is stable at 10 ms for flow rates up to 1 m3 h-1. At a higher flow rate, the cycle becomes unstable.

  4. Genome sequence of the filamentous, gliding Thiothrix nivea neotype strain (JP2T)

    SciTech Connect

    Lapidus, Alla L.; Nolan, Matt; Lucas, Susan; Glavina Del Rio, Tijana; Tice, Hope; Cheng, Jan-Fang; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne A.; Pitluck, Sam; Liolios, Konstantinos; Pagani, Ioanna; Ivanova, N; Huntemann, Marcel; Mavromatis, K; Mikhailova, Natalia; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Land, Miriam L; Brambilla, Evelyne-Marie; Rohde, Manfred; Abt, Birte; Verbarg, Susanne; Goker, Markus; Bristow, James; Eisen, Jonathan; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C; Klenk, Hans-Peter; Woyke, Tanja

    2011-01-01

    Thiothrix nivea (Rabenhorst 1865) Winogradsky 1888 (Approved Lists 1980) emend. Larkin and Shinabarger 1983 is the type species of the genus Thiothrix in the family Thiotrichaceae. The species is of interest not only because of its isolated location in the yet to be genomically characterized region of the tree of life, but also because of its life-style with gliding gonidia, the multilayer sheath, rosettes, and the embedded sulfur granules. Strain JP2T is the neotype strain of the species which was first observed by Rabenhorst in 1865 and later reclassified by Winogradsky in 1888 into the then novel genus Thiothrix. This is the first completed (im- proved-high-quality-draft) genome sequence to be published of a member of the family Thio- trichaceae. The genome in its current assembly consists of 15 contigs in four scaffolds with a total of 4,691,711 bp bearing 4,542 protein-coding and 52 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  5. Aerodynamics of the flying snake Chrysopelea paradisi: how a bluff body cross-sectional shape contributes to gliding performance.

    PubMed

    Holden, Daniel; Socha, John J; Cardwell, Nicholas D; Vlachos, Pavlos P

    2014-02-01

    A prominent feature of gliding flight in snakes of the genus Chrysopelea is the unique cross-sectional shape of the body, which acts as the lifting surface in the absence of wings. When gliding, the flying snake Chrysopelea paradisi morphs its circular cross-section into a triangular shape by splaying its ribs and flattening its body in the dorsoventral axis, forming a geometry with fore-aft symmetry and a thick profile. Here, we aimed to understand the aerodynamic properties of the snake's cross-sectional shape to determine its contribution to gliding at low Reynolds numbers. We used a straight physical model in a water tunnel to isolate the effects of 2D shape, analogously to studying the profile of an airfoil of a more typical flyer. Force measurements and time-resolved (TR) digital particle image velocimetry (DPIV) were used to determine lift and drag coefficients, wake dynamics and vortex-shedding characteristics of the shape across a behaviorally relevant range of Reynolds numbers and angles of attack. The snake's cross-sectional shape produced a maximum lift coefficient of 1.9 and maximum lift-to-drag ratio of 2.7, maintained increases in lift up to 35 deg, and exhibited two distinctly different vortex-shedding modes. Within the measured Reynolds number regime (Re=3000-15,000), this geometry generated significantly larger maximum lift coefficients than many other shapes including bluff bodies, thick airfoils, symmetric airfoils and circular arc airfoils. In addition, the snake's shape exhibited a gentle stall region that maintained relatively high lift production even up to the highest angle of attack tested (60 deg). Overall, the cross-sectional geometry of the flying snake demonstrated robust aerodynamic behavior by maintaining significant lift production and near-maximum lift-to-drag ratios over a wide range of parameters. These aerodynamic characteristics help to explain how the snake can glide at steep angles and over a wide range of angles of attack

  6. Mycoplasma pneumoniae: Current Knowledge on Macrolide Resistance and Treatment

    PubMed Central

    Pereyre, Sabine; Goret, Julien; Bébéar, Cécile

    2016-01-01

    Mycoplasma pneumoniae causes community-acquired respiratory tract infections, particularly in school-aged children and young adults. These infections occur both endemically and epidemically worldwide. M. pneumoniae lacks cell wall and is subsequently resistant to beta-lactams and to all antimicrobials targeting the cell wall. This mycoplasma is intrinsically susceptible to macrolides and related antibiotics, to tetracyclines and to fluoroquinolones. Macrolides and related antibiotics are the first-line treatment of M. pneumoniae respiratory tract infections mainly because of their low MIC against the bacteria, their low toxicity and the absence of contraindication in young children. The newer macrolides are now the preferred agents with a 7-to-14 day course of oral clarithromycin or a 5-day course of oral azithromycin for treatment of community-acquired pneumonia due to M. pneumoniae, according to the different guidelines worldwide. However, macrolide resistance has been spreading for 15 years worldwide, with prevalence now ranging between 0 and 15% in Europe and the USA, approximately 30% in Israel and up to 90–100% in Asia. This resistance is associated with point mutations in the peptidyl-transferase loop of the 23S rRNA and leads to high-level resistance to macrolides. Macrolide resistance-associated mutations can be detected using several molecular methods applicable directly from respiratory specimens. Because this resistance has clinical outcomes such as longer duration of fever, cough and hospital stay, alternative antibiotic treatment can be required, including tetracyclines such as doxycycline and minocycline or fluoroquinolones, primarily levofloxacin, during 7–14 days, even though fluoroquinolones and tetracyclines are contraindicated in all children and in children < 8 year-old, respectively. Acquired resistance to tetracyclines and fluoroquinolones has never been reported in M. pneumoniae clinical isolates but reduced susceptibility was reported

  7. Mycoplasma pneumoniae: Current Knowledge on Macrolide Resistance and Treatment.

    PubMed

    Pereyre, Sabine; Goret, Julien; Bébéar, Cécile

    2016-01-01

    Mycoplasma pneumoniae causes community-acquired respiratory tract infections, particularly in school-aged children and young adults. These infections occur both endemically and epidemically worldwide. M. pneumoniae lacks cell wall and is subsequently resistant to beta-lactams and to all antimicrobials targeting the cell wall. This mycoplasma is intrinsically susceptible to macrolides and related antibiotics, to tetracyclines and to fluoroquinolones. Macrolides and related antibiotics are the first-line treatment of M. pneumoniae respiratory tract infections mainly because of their low MIC against the bacteria, their low toxicity and the absence of contraindication in young children. The newer macrolides are now the preferred agents with a 7-to-14 day course of oral clarithromycin or a 5-day course of oral azithromycin for treatment of community-acquired pneumonia due to M. pneumoniae, according to the different guidelines worldwide. However, macrolide resistance has been spreading for 15 years worldwide, with prevalence now ranging between 0 and 15% in Europe and the USA, approximately 30% in Israel and up to 90-100% in Asia. This resistance is associated with point mutations in the peptidyl-transferase loop of the 23S rRNA and leads to high-level resistance to macrolides. Macrolide resistance-associated mutations can be detected using several molecular methods applicable directly from respiratory specimens. Because this resistance has clinical outcomes such as longer duration of fever, cough and hospital stay, alternative antibiotic treatment can be required, including tetracyclines such as doxycycline and minocycline or fluoroquinolones, primarily levofloxacin, during 7-14 days, even though fluoroquinolones and tetracyclines are contraindicated in all children and in children < 8 year-old, respectively. Acquired resistance to tetracyclines and fluoroquinolones has never been reported in M. pneumoniae clinical isolates but reduced susceptibility was reported in in

  8. Mycoplasma hyorhinis-encoded cytidine deaminase efficiently inactivates cytosine-based anticancer drugs.

    PubMed

    Vande Voorde, Johan; Vervaeke, Peter; Liekens, Sandra; Balzarini, Jan

    2015-01-01

    Mycoplasmas may colonize tumor tissue in patients. The cytostatic activity of gemcitabine was dramatically decreased in Mycoplasma hyorhinis-infected tumor cell cultures compared with non-infected tumor cell cultures. This mycoplasma-driven drug deamination could be prevented by exogenous administration of the cytidine deaminase (CDA) inhibitor tetrahydrouridine, but also by the natural nucleosides or by a purine nucleoside phosphorylase inhibitor. The M. hyorhinis-encoded CDAHyor gene was cloned, expressed as a recombinant protein and purified. CDAHyor was found to be more catalytically active than its human equivalent and efficiently deaminates (inactivates) cytosine-based anticancer drugs. CDAHyor expression at the tumor site may result in selective drug inactivation and suboptimal therapeutic efficiency. PMID:26322268

  9. Mycoplasma columbinum Isolated From a Racing Pigeon ( Columba livia ) With Arthritis.

    PubMed

    Hellebuyck, Tom; Garmyn, An; De Cooman, Lien; Boyen, Filip; Pasmans, Frank; Martel, An

    2014-09-01

    A juvenile racing pigeon ( Columba livia ) was presented with drooping of the wing and inability to fly. On physical examination, the right shoulder joint was swollen. The pigeon was euthanatized and submitted for necropsy. An excessive amount of fibrin was present in the canalis triosseus with severe arthritis of the affected shoulder joint. A pure growth of Mycoplasma-like colonies was obtained on microbiological culture of the shoulder joint. A 16S ribosomal RNA gene-specific polymerase chain reaction assay was performed on the isolate and revealed 100% similarity with Mycoplasma columbinum . Although infectious arthritis in homing pigeons is primarily associated with paratyphoid and Streptococcus gallolyticus infection, clinical practitioners should consider the potential role of Mycoplasma columbinum in arthritis in pigeons. PMID:25843324

  10. Hypogammaglobulinemic patient with polyarthritis mimicking rheumatoid arthritis finally diagnosed as septic arthritis caused by Mycoplasma hominis.

    PubMed

    Sato, Hiroe; Iino, Noriaki; Ohashi, Riuko; Saeki, Takako; Ito, Tomoyuki; Saito, Maki; Tsubata, Yutaka; Yamamoto, Suguru; Murakami, Shuichi; Kuroda, Takeshi; Tanabe, Yoshinari; Fujisawa, Junichi; Murai, Takehiro; Nakano, Masaaki; Narita, Ichiei; Gejyo, Fumitake

    2012-01-01

    Hypogammaglobulinemia is a reduction or absence of immunoglobulin, which may be congenital or associated with immunosuppressive therapy. In addition to infectious diseases, autoimmune diseases have also been reported in patients with hypogammaglobulinemia. A 26-year-old man with hypogammaglobulinemia had multiple joint pain and swelling with erosive changes in the proximal interphalangeal joint of the right middle finger on X-ray film, mimicking rheumatoid arthritis (RA). As polyarthritis remained after immunoglobulin replacement therapy and there was no finding indicating any infection at that time, a diagnosis of RA was made. Prednisolone and etanercept were started. However, his polyarthritis did not improve and he developed meningitis and massive brain ischemia. Finally, a diagnosis of disseminated Mycoplasma hominis infection was made. The differential diagnosis of polyarthritis in patients with hypogammaglobulinemia should strictly exclude Mycoplasma infection by culture with special media or longer anaerobic culture, and molecular methods for mycoplasma. PMID:22333381

  11. Mycoplasma lagogenitalium sp. nov., from the preputial smegma of Afghan pikas (Ochotona rufescens rufescens).

    PubMed

    Kobayashi, H; Runge, M; Schmidt, R; Kubo, M; Yamamoto, K; Kirchhoff, H

    1997-10-01

    Organisms with characteristics typical of mycoplasmas were isolated from the preputial smegma of Afghan picas (Ochotona rufescens rufescens). The results of growth inhibition tests, metabolic inhibition tests, and immunobinding assays showed that the isolated strains were identical and that they were distinct from previously described Mycoplasma, Entomoplasma, Mesoplasma, and Acholeplasma species. These organisms represent a new species, for which the name Mycoplasma lagogenitalium is proposed. M. lagogenitalium ferments glucose, does not hydrolyze arginine or urea, reduces tetrazolium chloride, possesses phosphatase activity, does not digest gelatin or casein, and does not produce films or spots. It lyses sheep erythrocytes and does not adsorb sheep, rabbit, or horse erythrocytes. Cholesterol or serum is required for growth. The growth temperature is 37 degrees C. The guanine-plus-cytosine content of the DNA is 23.0 +/- 1.0 mol%. The type strain is M. lagogenitalium 12MS (= ATCC 700289T). PMID:9336930

  12. Role of Mycoplasma and ureaplasma species in female lower genital tract infections.

    PubMed

    Patel, Meghan Arvind; Nyirjesy, Paul

    2010-11-01

    Genital mycoplasmas are commonly found in the female genital tract. Despite ongoing debate, the evidence that they cause lower genital tract disease in women remains sparse. The data that Mycoplasma genitalium is primarily transmitted sexually are accumulating, but its role as a cause of symptomatic urethritis or cervicitis is open to debate. Although Mycoplasma hominis may be a co-factor in bacterial vaginosis, it has otherwise not been implicated as a cause of lower tract disease. Now that Ureaplasma urealyticum has been divided into U. urealyticum and Ureaplasma parvum, their role in causing urethritis and cervicitis remains even more unclear. To date, no convincing evidence exists that antimicrobial therapy should be directed solely at these organisms when treating women with urethritis, bacterial vaginosis, trichomoniasis, or cervicitis. PMID:21308549

  13. Mycoplasmas and Their Antibiotic Resistance: The Problems and Prospects in Controlling Infections

    PubMed Central

    Chernova, O.A.; Medvedeva, E.S.; Mouzykantov, A.A.; Baranova, N.B.; Chernov, V.M.

    2016-01-01

    The present review discusses the problem of controlling mycoplasmas (class Mollicutes), the smallest of self-replicating prokaryotes, parasites of higher eukaryotes, and main contaminants of cell cultures and vaccines. Possible mechanisms for the rapid development of resistance to antimicrobial drugs in mycoplasmas have been analyzed. Omics technologies provide new opportunities for investigating the molecular basis of bacterial adaptation to stress factors and identifying resistomes, the total of all genes and their products contributing to antibiotic resistance in microbes. The data obtained using an integrated approach with post-genomics methods show that antibiotic resistance may be caused by more complex processes than has been believed heretofore. The development of antibiotic resistance in mycoplasmas is associated with essential changes in the genome, proteome, and secretome profiles, which involve many genes and proteins related to fundamental cellular processes and virulence. PMID:27437137

  14. Chlamydia trachomatis and Genital Mycoplasmas: Pathogens with an Impact on Human Reproductive Health

    PubMed Central

    Ljubin-Sternak, Sunčanica; Meštrović, Tomislav

    2014-01-01

    The most prevalent, curable sexually important diseases are those caused by Chlamydia trachomatis (C. trachomatis) and genital mycoplasmas. An important characteristic of these infections is their ability to cause long-term sequels in upper genital tract, thus potentially affecting the reproductive health in both sexes. Pelvic inflammatory disease (PID), tubal factor infertility (TFI), and ectopic pregnancy (EP) are well documented complications of C. trachomatis infection in women. The role of genital mycoplasmas in development of PID, TFI, and EP requires further evaluation, but growing evidence supports a significant role for these in the pathogenesis of chorioamnionitis, premature membrane rupture, and preterm labor in pregnant woman. Both C. trachomatis and genital mycoplasmas can affect the quality of sperm and possibly influence the fertility of men. For the purpose of this paper, basic, epidemiologic, clinical, therapeutic, and public health issue of these infections were reviewed and discussed, focusing on their impact on human reproductive health. PMID:25614838

  15. Lumbar vertebral morphology of flying, gliding, and suspensory mammals: implications for the locomotor behavior of the subfossil lemurs Palaeopropithecus and Babakotia.

    PubMed

    Granatosky, Michael C; Miller, Charlotte E; Boyer, Doug M; Schmitt, Daniel

    2014-10-01

    Lumbar vertebral morphology has been used as an indicator of locomotor behavior in living and fossil mammals. Rigidity within the lumbar region is thought to be important for increasing overall axial rigidity during various forms of locomotion, including bridging between supports, inverted quadrupedalism, gliding, and flying. However, distinguishing between those behaviors using bony features has been challenging. This study used osteological characters of the lumbar vertebrae to attempt to develop fine-grade functional distinctions among different mammalian species in order to make more complete inferences about how the axial skeleton affects locomotor behavior in extant mammals. These same lumbar characters were measured in two extinct species for which locomotor behaviors are well known, the sloth lemurs (Palaeopropithecus and Babakotia radofilai), in order to further evaluate their locomotor behaviors. Results from a principal components analysis of seven measurements, determined to be functionally significant from previous studies, demonstrate that inverted quadrupeds in the sample are characterized by dorsoventrally short and cranio-caudally expanded spinous processes, dorsally oriented transverse processes, and mediolaterally short and dorsoventrally high vertebral bodies compared with mammals that are relatively pronograde, vertical clingers, or gliders. Antipronograde mammals, dermopterans, and chiropterans also exhibit these traits, but not to the same extent as the inverted quadrupeds. In accordance with previous studies, our data show that the sloth lemur B. radofilai groups closely with antipronograde mammals like lorises, while Palaeopropithecus groups with extant sloths. These findings suggest that Palaeopropithecus was engaged in inverted quadrupedalism at a high frequency, while B. radofilai may have engaged in a more diverse array of locomotor and positional behaviors. The osteological features used here reflect differences in lumbar mobility

  16. Detection of mycoplasma infection in circulating tumor cells in patients with hepatocellular carcinoma

    SciTech Connect

    Choi, Hong Seo; Lee, Hyun Min; Kim, Won-Tae; Kim, Min Kyu; Chang, Hee Jin; Lee, Hye Ran; Joh, Jae-Won; Kim, Dae Shick; Ryu, Chun Jeih

    2014-04-04

    Highlights: • This study generates a monoclonal antibody CA27 against the mycoplasmal p37 protein. • CA27 isolates circulating tumor cells (CTCs) from the blood of liver cancer patients. • Results show the first evidence for mycoplasma infected-CTCs in cancer patients. - Abstract: Many studies have shown that persistent infections of bacteria promote carcinogenesis and metastasis. Infectious agents and their products can modulate cancer progression through the induction of host inflammatory and immune responses. The presence of circulating tumor cells (CTCs) is considered as an important indicator in the metastatic cascade. We unintentionally produced a monoclonal antibody (MAb) CA27 against the mycoplasmal p37 protein in mycoplasma-infected cancer cells during the searching process of novel surface markers of CTCs. Mycoplasma-infected cells were enriched by CA27-conjugated magnetic beads in the peripheral blood mononuclear cells in patients with hepatocellular carcinoma (HCC) and analyzed by confocal microscopy with anti-CD45 and CA27 antibodies. CD45-negative and CA27-positive cells were readily detected in three out of seven patients (range 12–30/8.5 ml blood), indicating that they are mycoplasma-infected circulating epithelial cells. CA27-positive cells had larger size than CD45-positive hematological lineage cells, high nuclear to cytoplasmic ratios and irregular nuclear morphology, which identified them as CTCs. The results show for the first time the existence of mycoplasma-infected CTCs in patients with HCC and suggest a possible correlation between mycoplasma infection and the development of cancer metastasis.

  17. In situ immunohistochemical detection of intracellular Mycoplasma salivarium in the epithelial cells of oral leukoplakia

    PubMed Central

    Mizuki, Harumi; Kawamura, Takafumi; Nagasawa, Dai

    2015-01-01

    Background Mycoplasmas are the smallest free-living organisms; Mycoplasma salivarium and Mycoplasma orale are the most common species isolated from the oropharynx. Oral leukoplakia is the most prevalent potentially malignant disorder of the oral mucosa; its etiology has not been defined. Our previous study with DNA-binding fluorescent dye suggested the presence of mycoplasmas in the epithelial cells of leukoplakia tissue. Objective Our aim was to detect M. salivarium in the epithelial cells of leukoplakia by immunohistochemistry. Design We produced a polyclonal antibody (PAb) reactive to Mycoplasma by injecting a rabbit with M. salivarium cells (ATCC 23064) mixed with complete Freund's adjuvant and a monoclonal antibody specific to M. salivarium by injecting M. salivarium cells (ATCC 23557) mixed with complete Freund's adjuvant into the footpads of a rat. Then, we attempted to detect M. salivarium in the epithelium of leukoplakia tissues by immunohistochemistry. Results We obtained an antimycoplasma rabbit PAb reactive to all seven Mycoplasma species used in this study. Three hybridoma clones producing monoclonal antibodies specific to M. salivarium were obtained, and an M. salivarium-specific monoclonal antibody, designated 7-6H, was established. Immunohistochemistry with these antibodies revealed M. salivarium in the epithelial cells of leukoplakia with hyperplasia and hyperkeratosis on histology. PCR and sequencing verified the presence of M. salivariumDNA in the epithelial cells of leukoplakia. Conclusion Intracellular M. salivarium was identified in the epithelial cells of leukoplakia. PMID:25065471

  18. Minimal genomes of mycoplasma-related endobacteria are plastic and contain host-derived genes for sustained life within Glomeromycota

    PubMed Central

    Naito, Mizue; Morton, Joseph B.; Pawlowska, Teresa E.

    2015-01-01

    Arbuscular mycorrhizal fungi (AMF, Glomeromycota) colonize roots of the majority of terrestrial plants. They provide essential minerals to their plant hosts and receive photosynthates in return. All major lineages of AMF harbor endobacteria classified as Mollicutes, and known as mycoplasma-related endobacteria (MRE). Except for their substantial intrahost genetic diversity and ability to transmit vertically, virtually nothing is known about the life history of these endobacteria. To understand MRE biology, we sequenced metagenomes of three MRE populations, each associated with divergent AMF hosts. We found that each AMF species harbored a genetically distinct group of MRE. Despite vertical transmission, all MRE populations showed extensive chromosomal rearrangements, which we attributed to genetic recombination, activity of mobile elements, and a history of plectroviral invasion. The MRE genomes are characterized by a highly reduced gene content, indicating metabolic dependence on the fungal host, with the mechanism of energy production remaining unclear. Several MRE genes encode proteins with domains involved in protein–protein interactions with eukaryotic hosts. In addition, the MRE genomes harbor genes horizontally acquired from AMF. Some of these genes encode small ubiquitin-like modifier (SUMO) proteases specific to the SUMOylation systems of eukaryotes, which MRE likely use to manipulate their fungal host. The extent of MRE genome plasticity and reduction, along with the large number of horizontally acquired host genes, suggests a high degree of adaptation to the fungal host. These features, together with the ubiquity of the MRE–Glomeromycota associations, emphasize the significance of MRE in the biology of Glomeromycota. PMID:25964324

  19. A serologic survey of Mycoplasma putrefaciens infection in goats.

    PubMed

    Abegunde, T O; Adler, H E; Farver, T B; DaMassa, A J

    1981-10-01

    The prevalence of Mycoplasma putrefaciens infection in goat populations in Mendocino and Sonoma counties of northern California was studied, using the plate and tube agglutination tests. On a county basis, Mendocino had a higher antibody prevalence (13%) than Sonoma (10%). The overall antibody prevalence among the 377 goat serum samples tested was 11%. There was no statistical evidence to show any significant difference in prevalence on the basis of herd size. Of the common goat breeds in California, the American La Mancha had the lowest prevalence (4.7%), the Toggenberg, highest (10.8%). Angora goats shipped from Texas showed a much higher prevalence (67%) than any of the California breeds. The age-specific risk calculations indicate that all age groups were more susceptible to M putrefaciens than 4-year-old goats, with the lowest prevalence of 3.8%. The highest prevalence (21.3%) was observed in the Angora goats. Males had a lower prevalence (10.7%) than females (16.1%). A flock of sheep included in the survey showed a prevalence of 15%. PMID:7325445

  20. Characterization of western X-disease mycoplasma-like organisms

    SciTech Connect

    Kirkpatrick, B.C.

    1986-01-01

    The causal agent of western X-disease, an important disease of cherry (Prunus avium) and peach (Prunus persica) in the western United States, was shown to be a non-culturable, mycoplasma-like organism (WX-MLO). Procedures were developed to purify WX-MLOs from celery and leafhoppers infected with a greenhouse-maintained isolate of the peach yellow leaf roll (ghPYLR) strain of western X-disease. WX-MLOs, purified from ghPYLR-infected leafhoppers, elicited the production of specific antisera (WX antisera) when injected into rabbits. When used in an enzyme-linked immunosorbent assay (ELISA), WX antisera quantitatively detected WX-MLOs in celery, periwinkle, and leafhoppers experimentally infected with either ghPYLR or the Green Valley (GVX) strain of western X-disease. Recombinant clones were screened by colony, dot and southern hybridizations using /sup 32/P-nick translated DNA extracted from healthy and ghPYLR-infected celery and leafhoppers. Twenty-four clones were identified which hybridized with DNA from diseased but not healthy hosts. DNA hybridization assays, using radiolabeled, cloned WX-MLO DNA, readily detected WX-MLOs in celery, periwinkle, and leafhoppers infected with either GVX or ghPYLR and in cherry and peach with symptoms of GVX.