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Sample records for mycoplasma mobile gliding

  1. 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

  2. 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

  3. Unitary step of gliding machinery in Mycoplasma mobile.

    PubMed

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

    2014-06-10

    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.

  4. Role of binding in Mycoplasma mobile and Mycoplasma pneumoniae gliding analyzed through inhibition by synthesized sialylated compounds.

    PubMed

    Kasai, Taishi; Nakane, Daisuke; Ishida, Hideharu; Ando, Hiromune; Kiso, Makoto; Miyata, Makoto

    2013-02-01

    Mycoplasmas, which have been shown to be the causative pathogens in recent human pneumonia epidemics, bind to solid surfaces and glide in the direction of the membrane protrusion at a pole. During gliding, the legs of the mycoplasma catch, pull, and release sialylated oligosaccharides fixed on a solid surface. Sialylated oligosaccharides are major structures on animal cell surfaces and are sometimes targeted by pathogens, such as influenza virus. In the present study, we analyzed the inhibitory effects of 16 chemically synthesized sialylated compounds on the gliding and binding of Mycoplasma mobile and Mycoplasma pneumoniae and concluded the following. (i) The recognition of sialylated oligosaccharide by mycoplasma legs proceeds in a "lock-and-key" fashion, with the binding affinity dependent on structural differences among the sialylated compounds examined. (ii) The binding of the leg and the sialylated oligosaccharide is cooperative, with Hill constants ranging from 2 to 3. (iii) Mycoplasma legs may generate a drag force after a stroke, because the gliding speed decreased and pivoting motion occurred more frequently when the number of working legs was reduced by the addition of free sialylated compounds.

  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. Analysis of energy sources for Mycoplasma penetrans gliding motility.

    PubMed

    Jurkovic, Dominika A; Hughes, Michael R; Balish, Mitchell F

    2013-01-01

    Mycoplasma penetrans, a potential human pathogen found mainly in HIV-infected individuals, uses a tip structure for both adherence and gliding motility. To improve our understanding of the molecular mechanism of M. penetrans gliding motility, we used chemical inhibitors of energy sources associated with motility of other organisms to determine which of these is used by M. penetrans and also tested whether gliding speed responded to temperature and pH. Mycoplasma penetrans gliding motility was not eliminated in the presence of a proton motive force inhibitor, a sodium motive force inhibitor, or an agent that depletes cellular ATP. At near-neutral pH, gliding speed increased as temperature increased. The absence of a clear chemical energy source for gliding motility and a positive correlation between speed and temperature suggest that energy derived from heat provides the major source of power for the gliding motor of M. penetrans.

  7. Mycoplasma genitalium mg200 and mg386 genes are involved in gliding motility but not in cytadherence.

    PubMed

    Pich, Oscar Q; Burgos, Raul; Ferrer-Navarro, Mario; Querol, Enrique; Piñol, Jaume

    2006-06-01

    Isolation and characterization of transposon-generated Mycoplasma genitalium gliding-deficient mutants has implicated mg200 and mg386 genes in gliding motility. The proposed role of these genes was confirmed by restoration of the gliding phenotype in deficient mutants through gene complementation with their respective mg386 or mg200 wild-type copies. mg200 and mg386 are the first reported gliding-associated mycoplasma genes not directly involved in cytadherence. Orthologues of MG200 and MG386 proteins are also found in the slow gliding mycoplasmas, Mycoplasma pneumoniae and Mycoplasma gallisepticum, suggesting the existence of a unique set of proteins involved in slow gliding motility. MG200 and MG386 proteins share common features, such as the presence of enriched in aromatic and glycine residues boxes and an acidic and proline-rich domain, suggesting that these motifs could play a significant role in gliding motility.

  8. A Major Determinant for Gliding Motility in Mycoplasma genitalium

    PubMed Central

    Martinelli, Luca; Lalli, Daniela; García-Morales, Luis; Ratera, Mercè; Querol, Enrique; Piñol, Jaume; Fita, Ignacio; Calisto, Bárbara M.

    2015-01-01

    Several mycoplasmas, such as the emergent human pathogen Mycoplasma genitalium, developed a complex polar structure, known as the terminal organelle (TO), responsible for a new type of cellular motility, which is involved in a variety of cell functions: cell division, adherence to host cells, and virulence. The TO cytoskeleton is organized as a multisubunit dynamic motor, including three main ultrastructures: the terminal button, the electrodense core, and the wheel complex. Here, we describe the interaction between MG200 and MG491, two of the main components of the TO wheel complex that connects the TO with the cell body and the cell membrane. The interaction between MG200 and MG491 has a KD in the 80 nm range, as determined by surface plasmon resonance. The interface between the two partners was confined to the “enriched in aromatic and glycine residues” (EAGR) box of MG200, previously described as a protein-protein interaction domain, and to a 25-residue-long peptide from the C-terminal region of MG491 by surface plasmon resonance and NMR spectroscopy studies. An atomic description of the MG200 EAGR box binding surface was also provided by solution NMR. An M. genitalium mutant lacking the MG491 segment corresponding to the peptide reveals specific alterations in cell motility and cell morphology indicating that the MG200-MG491 interaction plays a key role in the stability and functioning of the TO. PMID:25471372

  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. Structural Study of MPN387, an Essential Protein for Gliding Motility of a Human-Pathogenic Bacterium, Mycoplasma pneumoniae

    PubMed Central

    Kawakita, Yoshito; Kinoshita, Miki; Furukawa, Yukio; Tulum, Isil; Tahara, Yuhei O.; Katayama, Eisaku

    2016-01-01

    ABSTRACT Mycoplasma pneumoniae is a human pathogen that glides on host cell surfaces with repeated catch and release of sialylated oligosaccharides. At a pole, this organism forms a protrusion called the attachment organelle, which is composed of surface structures, including P1 adhesin and the internal core structure. The core structure can be divided into three parts, the terminal button, paired plates, and bowl complex, aligned in that order from the front end of the protrusion. To elucidate the gliding mechanism, we focused on MPN387, a component protein of the bowl complex which is essential for gliding but dispensable for cytadherence. The predicted amino acid sequence showed that the protein features a coiled-coil region spanning residue 72 to residue 290 of the total of 358 amino acids in the protein. Recombinant MPN387 proteins were isolated with and without an enhanced yellow fluorescent protein (EYFP) fusion tag and analyzed by gel filtration chromatography, circular dichroism spectroscopy, analytical ultracentrifugation, partial proteolysis, and rotary-shadowing electron microscopy. The results showed that MPN387 is a dumbbell-shaped homodimer that is about 42.7 nm in length and 9.1 nm in diameter and includes a 24.5-nm-long central parallel coiled-coil part. The molecular image was superimposed onto the electron micrograph based on the localizing position mapped by fluorescent protein tagging. A proposed role of this protein in the gliding mechanism is discussed. IMPORTANCE Human mycoplasma pneumonia is caused by a pathogenic bacterium, Mycoplasma pneumoniae. This tiny, 2-μm-long bacterium is suggested to infect humans by gliding on the surface of the trachea through binding to sialylated oligosaccharides. The mechanism underlying mycoplasmagliding motility” is not related to any other well-studied motility systems, such as bacterial flagella and eukaryotic motor proteins. Here, we isolated and analyzed the structure of a key protein which is

  11. Kinematic Analyses of the Thumb during Simulated Posteroanterior Glide Mobilization

    PubMed Central

    Su, Fong-Chin

    2016-01-01

    Objective Thumb problems are common in some health professionals such as physical therapists. The purpose of this case-control study is to investigate the influence of clinical experience and different mobilization techniques on the kinematics of the thumb. Methods Twenty-three participants without exposure to manual techniques (the Novice Group) and fifteen physical therapists with at least 3 years of orthopedic experience (the Experienced Group) participated. The kinematics of the thumb while performing 3 different simulated posteroanterior (PA) glide mobilization techniques on a load cell was monitored. These 3 techniques were: 1) unsupported, 2) with digital support and 3) with thumb interphalangeal joint supported by the index finger. The amount of forces exerted were 25% to 100% of maximum effort at 25% increments. The main effects of experience and technique on thumb kinematics were assessed. Results Both experience and technique had main effects on the flexion/extension angles of the thumb joints. Experienced participants assumed a more flexed position at the carpometacarpal (CMC) joint, and the novice participants performed with angles closer to the neutral position (F = 7.593, p = 0.010). Participants’ metacarpophalangeal (MCP) joints were in a more flexed position while performing PA glide with thumb interphalangeal (IP) joint supported by the index as compared to the other two techniques (p < .001). Conclusions Negative correlations were generally obtained between the sagittal plane angles of adjacent thumb joints during mobilization/manipulation. Therapists are recommended to treat patient with more stable PA glide mobilization techniques, such as PA glide with thumb interphalangeal joint supported by the index finger, to prevent potential mobilization-related thumb disorders. PMID:27583407

  12. Role of Mycoplasma genitalium MG218 and MG317 cytoskeletal proteins in terminal organelle organization, gliding motility and cytadherence.

    PubMed

    Pich, Oscar Q; Burgos, Raul; Ferrer-Navarro, Mario; Querol, Enrique; Piñol, Jaume

    2008-10-01

    The terminal organelle is a differentiated structure that plays a key role in mycoplasma cytadherence and locomotion. For this reason, the analysis of Mycoplasma genitalium mutants displaying anomalous terminal organelles could improve our knowledge regarding the structural elements required for proper locomotion. In this study, we isolated several M. genitalium mutants having transposon insertions within the mg218 or mg317 genes, which encode the orthologues of Mycoplasma pneumoniae HMW2 and HMW3 cytoskeletal proteins, respectively. As expected, mg218(-) and mg317(-) mutants exhibit a reduced gliding motility, although their ability to attach to solid surfaces was not completely abolished. Interestingly, most of the mg218(-) mutants expressed N-terminal MG218 derivatives and showed the presence of short terminal organelles retaining many of the functions displayed by this structure in the wild-type strain, suggesting that the N-terminal region of this protein is an essential element in the architecture of the terminal organelle. Separately, the analysis of mg317(-) mutants indicates that MG317 protein is involved in the formation of the terminal button and contributes to anchoring the electron-dense core to the cell membrane. The results presented here clearly show that MG218 and MG317 proteins are implicated in the maintenance of gliding motility and cytadherence in M. genitalium.

  13. 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

  14. Cell surface differentiation of Mycoplasma mobile visualized by surface protein localization.

    PubMed

    Kusumoto, Akiko; Seto, Shintaro; Jaffe, Jacob D; Miyata, Makoto

    2004-12-01

    Mycoplasma mobile has a flask-shaped cell morphology and glides toward its tapered end at a rate of 3-7 cell lengths per s (2.0-4.5 microm s(-1)) by an unknown mechanism. Gliding requires that the surface of the cell is in contact with a solid substrate, such as glass or plastic. In order to characterize the nature of the outer surface of M. mobile, monoclonal antibodies were raised against intact cells and screened for their ability to recognize surface proteins. Four antibodies were identified and their protein targets were determined. One antibody recognized the Gli349 protein, which is known to be involved in glass binding and gliding. This antibody was also able to displace attached M. mobile cells from glass, suggesting that Gli349 is the major adhesion protein in M. mobile. The other three antibodies recognized members of the Mvsp family of proteins, which are presumably the major surface antigens of M. mobile. Immunofluorescence studies were performed to localize these proteins on the surface of M. mobile cells. Gli349 localized to the proximal region of the tapered part of the cell (the 'neck'), while the various Mvsp family members showed several distinct patterns of subcellular localization. MvspN and MvspO localized to the distal end of the tapered part of the cell (the 'head'), MvspK localized to the main part of the cell (the 'body'), and MvspI localized to both the head and body but not the neck. This analysis shows that M. mobile surprisingly expresses multiple versions of its major surface antigen at once but differentiates its surface by differential localization of the various paralogues.

  15. 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.

  16. "Mycoplasmal antigen modulation," a novel surface variation suggested for a lipoprotein specifically localized on Mycoplasma mobile.

    PubMed

    Wu, Heng Ning; Kawaguchi, Chie; Nakane, Daisuke; Miyata, Makoto

    2012-05-01

    Mycoplasma mobile, a pathogen of freshwater fish, glides easily across surfaces, colonizes on the fish gill, and causes necrosis. The cell surface is differentiated into three parts: the head, neck, and body. Mobile variable surface proteins (Mvsps) localizing at each of these parts may be involved in surface variation including phase variation and antigenic variation, although no proof exists. In this study, we examined this possibility by focusing on MvspI, the largest Mvsp. Immunofluorescence microscopy showed that MvspI is expressed on the surfaces of all cells. When anti-MvspI antibody was added at concentrations over 0.8 nM, MvspI was observed to decrease over time. After 72 h of cultivation with the antibody, the fluorescence intensity and amount of MvspI decreased up to 13 and 39%, respectively, compared to those of cells grown without antibody. These changes were reversed by the removal of the antibody. Such effects were not observed when another antibody targeting other Mvsps was used, suggesting that the decrease is specific to the relationship between MvspI and the antibody. Cell growth was also inhibited by the antibody, but the decrease in MvspI could not be explained by the selective growth of MvspI-negative variants or by the inhibition of growth with other conditions. The decrease in MvspI caused by the antibody binding may suggest a novel type of surface variation, designated here as "mycoplasmal antigen modulation."

  17. Toward single molecule detection of staphylococcal enterotoxin B: mobile sandwich immunoassay on gliding microtubules.

    PubMed

    Soto, Carissa M; Martin, Brett D; Sapsford, Kim E; Blum, Amy Szuchmacher; Ratna, Banahalli R

    2008-07-15

    An immunoassay based on gliding microtubules (MTs) is described for the detection of staphylococcal enterotoxin B. Detection is performed in a sandwich immunoassay format. Gliding microtubules carry the antigen-specific "capture" antibody, and bound analyte is detected using a fluorescent viral scaffold as the tracer. A detailed modification scheme for the MTs postpolymerization is described along with corresponding quantification by fluorescence spectroscopy. The resultant antibody-MTs maintain their morphology and gliding capabilities. We report a limit of detection down to 0.5 ng/mL during active transport in a 30 min assay time and down to 1 ng/mL on static surfaces. This study demonstrates the kinesin/MT-mediated capture, transport, and detection of the biowarfare agent SEB in a microfluidic format.

  18. A major determinant for gliding motility in Mycoplasma genitalium: the interaction between the terminal organelle proteins MG200 and MG491.

    PubMed

    Martinelli, Luca; Lalli, Daniela; García-Morales, Luis; Ratera, Mercè; Querol, Enrique; Piñol, Jaume; Fita, Ignacio; Calisto, Bárbara M

    2015-01-16

    Several mycoplasmas, such as the emergent human pathogen Mycoplasma genitalium, developed a complex polar structure, known as the terminal organelle (TO), responsible for a new type of cellular motility, which is involved in a variety of cell functions: cell division, adherence to host cells, and virulence. The TO cytoskeleton is organized as a multisubunit dynamic motor, including three main ultrastructures: the terminal button, the electrodense core, and the wheel complex. Here, we describe the interaction between MG200 and MG491, two of the main components of the TO wheel complex that connects the TO with the cell body and the cell membrane. The interaction between MG200 and MG491 has a KD in the 80 nm range, as determined by surface plasmon resonance. The interface between the two partners was confined to the "enriched in aromatic and glycine residues" (EAGR) box of MG200, previously described as a protein-protein interaction domain, and to a 25-residue-long peptide from the C-terminal region of MG491 by surface plasmon resonance and NMR spectroscopy studies. An atomic description of the MG200 EAGR box binding surface was also provided by solution NMR. An M. genitalium mutant lacking the MG491 segment corresponding to the peptide reveals specific alterations in cell motility and cell morphology indicating that the MG200-MG491 interaction plays a key role in the stability and functioning of the TO.

  19. EMG activity of selected rotator cuff musculature during grade III distraction and posterior glide glenohumeral mobilization: results of a pilot trial comparing painful and non-painful shoulders

    PubMed Central

    Swanson, Brian T.; Holst, Brian; Infante, John; Poenitzsch, James; Ortiz, Alexis

    2016-01-01

    Objectives The objectives of this pilot study were to investigate rotator cuff activity that may be present during grade III distraction and posterior glide mobilization of the glenohumeral (GH) joint, as well as to examine any differences in response between painful and non-painful shoulders utilizing these techniques. Methods EMG data were collected using Delsys EMGworks® software and Trigno® mini-wireless electrodes for the supraspinatus, infraspinatus and upper trapezius musculature during grade III GH distraction and posterior glide mobilization. A total of 20 shoulders (10 painful, 10 non-painful) were recruited from a sample of convenience. Submaximal voluntary dynamic contraction against gravity was used as reference for each of the three selected muscles. Participants underwent two trials of each mobilization, and the mean results for each group were assessed using descriptive statistics (mean, standard deviation) and effect size. Results Both the painful and non-painful groups exhibited considerable levels of rotator cuff activity during each test parameter, with the painful group consistently generating higher supraspinatus and infraspinatus RMS and peak force activity. Analysis of the peak combined rotator cuff activity during distraction (d = 0.58) and posterior glides (d = 0.64) suggests moderate-to-high practical significance of the results. Discussion GH distraction and posterior glide mobilizations have traditionally been thought of as passive treatment procedures. The results of this pilot study indicate that the supraspinatus and infraspinatus are significantly active during these techniques. Findings suggest that during these techniques, the total infra/supraspinatus EMG activity approaches the level produced while raising the arm against gravity. Level of evidence: 2b PMID:27252577

  20. Strain on the repaired supraspinatus tendon during manual traction and translational glide mobilization on the glenohumeral joint: a cadaveric biomechanics study.

    PubMed

    Muraki, Takayuki; Aoki, Mitsuhiro; Uchiyama, Eiichi; Miyasaka, Tomoya; Murakami, Gen; Miyamoto, Shigenori

    2007-08-01

    There has been no report on the mechanical effects of joint mobilization on rotator cuffs. The purpose of this study was to determine whether it is safe to use grade 3 joint mobilization techniques after rotator cuff repair. Nine fresh frozen cadaveric shoulders were used in this study. The strains on the artificially repaired supraspinatus tendon during joint mobilization were measured at 0 degrees and 30 degrees of shoulder abduction and were compared with those at the maximal stretching position and relaxing position. Additionally, gap distances were measured during this experiment. The strain at 30 degrees of abduction of the repaired tendon during each joint mobilization was significantly smaller than that at 0 degrees abduction (P<0.05). At 30 degrees of abduction, the strain during joint mobilization was not statistically different from that of the shoulder in the relaxing position, except during the inferior glide technique. Gap distances were 0mm at 30 degrees , while the distances were 1.06-1.46 mm at 0 degrees. Our findings suggest that joint mobilization techniques, except inferior glide, can be performed safely without significantly straining the repaired tendon at 30 degrees of abduction, if rotator cuff repair is performed at 0 degrees of abduction.

  1. Molecular Structure of Isolated MvspI, a Variable Surface Protein of the Fish Pathogen Mycoplasma mobile

    PubMed Central

    Adan-Kubo, Jun; Yoshii, Shu-hei; Kono, Hidetoshi

    2012-01-01

    Mycoplasma mobile is a parasitic bacterium that causes necrosis in the gills of freshwater fishes. This study examines the molecular structure of its variable surface protein, MvspI, whose open reading frame encodes 2,002 amino acids. MvspI was isolated from mycoplasma cells by a biochemical procedure to 92% homogeneity. Gel filtration and analytical ultracentrifugation suggested that this protein is a cylinder-shaped monomer with axes of 66 and 2.7 nm. Rotary shadowing transmission electron microscopy of MvspI showed that the molecule is composed of two rods 30 and 45 nm long; the latter rod occasionally features a bulge. Immuno-electron microscopy and epitope mapping showed that the bulge end of the molecular image corresponds to the C terminus of the amino acid sequence. Partial digestion by various proteases suggested that the N-terminal part, comprised of 697 amino acids, is flexible. Analysis of the predicted amino acid sequence showed that the molecule features a lipoprotein and 16 repeats of about 90 residues; 15 positions exist between residues 88 and 1479, and the other position is between residues 1725 and 1807. The amino acid sequence of MvspI was mapped onto a molecular image obtained by electron microscopy. The present study is the first to elucidate the molecular shape of a variable surface protein of mycoplasma. PMID:22447898

  2. The effects of posterior talar glide with dorsiflexion of the ankle on mobility, muscle strength and balance in stroke patients: a randomised controlled trial

    PubMed Central

    Lee, Jin; Kim, Ju-O; Lee, Byoung-Hee

    2017-01-01

    [Purpose] The purpose of this study was to examine the effectiveness of posterior talar glide (PTG) with dorsiflexion of the ankle on stroke patients ankle mobility, muscle strength, and balance ability. [Subjects and Methods] Thirty-four subjects were randomly assigned to either a PTG with dorsiflexion group (PTG; n=17), or a weight-bearing with placebo PTG group (control; n=17). Subjects in the PTG group performed PTG with dorsiflexion, designed to improve ankle mobility, muscle strength and balance ability with proprioceptive control of the ankle, for 10 glides of 5 sets/day, 5 days/week, for 4 weeks. [Results] The experimental group showed significant improvement on the Ankle Dorsiflexion Range of Motion assessment, Ankle Dorsiflexor Manual Muscle Test, Functional Reach Test, Time Up and Go test, and Functional Gait Assessment compared to the control group. However, regarding Ankle Plantarflexion Range of Motion assessment and the Ankle Plantarflexor Manual Muscle Test, no significant differences were found between the two groups. [Conclusion] The results of this study show that PTG with dorsiflexion can improve ankle mobility, muscle strength and balance ability in patients recovering from stroke. This exercise may prove useful in clinical rehabilitation. Further research on the long-term effectiveness of PTG on gait ability is suggested. PMID:28356629

  3. Mycoplasma pneumonia

    MedlinePlus

    Walking pneumonia; Community-acquired pneumonia - mycoplasma; Community-acquired pneumonia - atypical ... Mycoplasma pneumonia usually affects people younger than 40. People who live or work in crowded areas such ...

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

    PubMed

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

    2015-03-26

    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.

  5. Dynamics of glide avalanches and snow gliding

    NASA Astrophysics Data System (ADS)

    Ancey, Christophe; Bain, Vincent

    2015-09-01

    In recent years, due to warmer snow cover, there has been a significant increase in the number of cases of damage caused by gliding snowpacks and glide avalanches. On most occasions, these have been full-depth, wet-snow avalanches, and this led some people to express their surprise: how could low-speed masses of wet snow exert sufficiently high levels of pressure to severely damage engineered structures designed to carry heavy loads? This paper reviews the current state of knowledge about the formation of glide avalanches and the forces exerted on simple structures by a gliding mass of snow. One particular difficulty in reviewing the existing literature on gliding snow and on force calculations is that much of the theoretical and phenomenological analyses were presented in technical reports that date back to the earliest developments of avalanche science in the 1930s. Returning to these primary sources and attempting to put them into a contemporary perspective are vital. A detailed, modern analysis of them shows that the order of magnitude of the forces exerted by gliding snow can indeed be estimated correctly. The precise physical mechanisms remain elusive, however. We comment on the existing approaches in light of the most recent findings about related topics, including the physics of granular and plastic flows, and from field surveys of snow and avalanches (as well as glaciers and debris flows). Methods of calculating the forces exerted by glide avalanches are compared quantitatively on the basis of two case studies. This paper shows that if snow depth and density are known, then certain approaches can indeed predict the forces exerted on simple obstacles in the event of glide avalanches or gliding snow cover.

  6. Mycoplasma viruses.

    PubMed

    Maniloff, J

    1988-01-01

    Unlike bacterial viruses that infect cells bounded by a cell wall, mycoplasma viruses have evolved to enter and propagate in mycoplasma cells bounded only by a single lipid-protein cell membrane. In addition, mycoplasmas have the smallest amount of genetic information of any known cells, so their complexity is constrained by a limited genetic coding capacity. As a consequence of these host cell differences, mycoplasma viruses have been found to have a variety of structures and replication strategies which are different from those of the bacterial viruses. This article is a critical review of mycoplasma viruses infecting the genera Acholeplasma, Spiroplasma, and Mycoplasma; included are data on classification, morphology and structure, biological and physical properties, chemical composition, and productive and lysogenic replication cycles.

  7. 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

  8. 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.

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

    PubMed

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

    2014-10-17

    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.

  10. Hang-gliding accidents.

    PubMed Central

    Margreiter, R; Lugger, L J

    1978-01-01

    Seventy-five known hang-gliding accidents causing injury to the pilot occurred in the Tyrol during 1973-6. Most occurred in May, June, or September and between 11 am and 3 pm, when unfavourable thermic conditions are most likely. Thirty-four accidents happened during launching, 13 during flight, and 28 during landing, and most were caused by human errors--especially deficient launching technique; incorrect estimation of wind conditions, altitude, and speed; and choice of unfavourable launching and landing sites. Eight pilots were moderately injured, 60 severely (multiply in 24 cases), and seven fatally; fractures of the spine and arms predominated. Six of the 21 skull injuries were fatal. The risk of hang-gliding seems unjustifiably high, and safety precautions and regulations should be adopted to ensure certain standards of training and equipment and to limit flying to favourable sites and times. Images p401-a PMID:624028

  11. On Dislocation Glide in Planetary Interiors

    NASA Astrophysics Data System (ADS)

    Cordier, P.; Carrez, P.; Gouriet, K.; Kraych, A.; Ritterbex, S.

    2015-12-01

    The dynamics of hot planets depends strongly on how heat is transported to their surfaces through large scale convection flows. This is ultimately controlled by the rheology of high-pressure phases under extreme conditions. Whenever solid rocks are concerned, plastic flow results from the propagation of crystal defects (point defects, dislocations, grain boundaries). In this presentation we focus on the role of pressure on dislocation glide which is usually the most efficient strain-producing mechanism. Dislocation glide is assessed through multiscale numerical modeling. First, dislocations are modeled at the atomic scale based on first-principles calculations to incorporate the influence of pressure. Then the mobility law of dislocation at finite temperature is modeled by describing thermally-activated mechanisms for dislocation glide based on the kink-pair model. Then the flow stress at the grain scale is deduced either from application of the Orowan equation or by dislocation dynamics modeling. This approach is applied to wadsleyite, ringwoodite, bridgmanite and post-perovskite. Mechanical properties are either calculated at laboratory strain-rates to be compared with experiments when available or at mantle strain-rate to assess their efficiency under natural conditions.

  12. 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.

  13. [Pathogenic factors of mycoplasma].

    PubMed

    Shimizu, Takashi

    2015-01-01

    Mycoplasmas are smallest organisms capable of self-replication and cause various diseases in human. Especially, Mycoplasma pneumoniae is known as an etiological agent of pneumonia. From 2010 to 2012, epidemics of M. pneumoniae infections were reported worldwide (e.g., in France, Israel, and Japan). In the diseases caused by mycoplasmas, strong inflammatory responses induced by mycoplasmas have been thought to be important. However, mycoplasmas lack of cell wall and do not possess inflammation-inducing endotoxin such as lipopolysaccharide (LPS). We purified inflammation-inducing factors from pathogenic mycoplasmas and identified that they were lipoproteins. Lipoproteins derived from mycoplasmas induced inflammatory responses through Toll-like receptor (TLR) 2. In addition, we demonstrated that cytadherent property of M. pneumoniae played an important role in induction of inflammatory responses. Cytadherent property of M. pneumoniae induced inflammatory responses through TLR2 independent pathway. TLR4, inflammasomes, and autophagy were involved in this TLR2 independent induction of inflammatory responses.

  14. Feline hemotropic mycoplasmas.

    PubMed

    Sykes, Jane E

    2010-11-01

    Three species of hemotropic mycoplasmas are known to infect cats worldwide, Mycoplasma haemofelis, "Candidatus Mycoplasma turicensis" and "Candidatus Mycoplasma haemominutum." These organisms were previously known as Haemobartonella felis, but are now known to be mycoplasmas. Assays based on polymerase chain reaction technology are the most sensitive and specific diagnostic tests available for these organisms. M haemofelis is the most pathogenic species, and causes hemolytic anemia in immunocompetent cats. Other differential diagnoses for hemolytic anemia should be considered in cats testing positive for "Candidatus Mycoplasma turicensis" and "Candidatus Mycoplasma haemominutum," because the presence of these organisms is not always associated with anemia. Blood from infected cats should be handled with care because of the potential zoonotic nature of hemoplasma infections. The treatment of choice for cats with clinical disease is doxycycline.

  15. The Physics of Hang Gliding

    NASA Astrophysics Data System (ADS)

    Hewett, Lionel D.

    2008-03-01

    Dr. Hewett has received both national and international awards from the hang gliding community for his contributions to the safety of towing hang gliders. These contributions were a consequence of his applying his knowledge of physics to the sport of hang gliding. This lecture illustrates how these and other applications of the fundamental principles of physics have influenced the historical evolutions of hang gliding and paragliding from the earliest flights of Otto Lilienthal in 1891 through the more recent record breaking flights of more than 430 miles from Zapata Texas.

  16. The Korean Prevocalic Palatal Glide: A Comparison with the Russian Glide and Palatalization.

    PubMed

    Suh, Yunju; Hwang, Jiwon

    2016-01-01

    Phonetic studies of the Korean prevocalic glides have often suggested that they are shorter in duration than those of languages like English, and lack a prolonged steady state. In addition, the formant frequencies of the Korean labiovelar glide are reported to be greatly influenced by the following vowel. In this study the Korean prevocalic palatal glide is investigated vis-à-vis the two phonologically similar configurations of another language - the glide /j/ and the secondary palatalization of Russian, with regard to the inherent duration of the glide component, F2 trajectory, vowel-to-glide coarticulation and glide-to-vowel coarticulation. It is revealed that the Korean palatal glide is closer to the Russian palatalization in duration and F2 trajectory, indicating a lack of steady state, and to the Russian segmental glide in the vowel-to-glide coarticulation degree. When the glide-to-vowel coarticulation is considered, the Korean palatal glide is distinguished from both Russian categories. The results suggest that both the Korean palatal glide and the Russian palatalization involve significant articulatory overlap, the former with the vowel and the latter with the consonant. Phonological implications of such a difference in coarticulation pattern are discussed, as well as the comparison between the Korean labiovelar and palatal glides.

  17. 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

  18. 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

    2013-03-06

    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.

  19. 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

  20. Use of polymerase chain reactions to detect Mycoplasma gallisepticum, Mycoplasma imitans, Mycoplasma iowae, Mycoplasma meleagridis and Mycoplasma synoviae in birds of prey.

    PubMed

    Lierz, M; Hagen, N; Lueschow, D; Hafez, H M

    2008-10-01

    Certain Mycoplasma spp. are pathogens of poultry, but little is known of the role of mycoplasmas in disease of birds of prey. Species-specific polymerase chain reactions (PCRs) for the detection of the poultry pathogens Mycoplasma gallisepticum, Mycoplasma imitans, Mycoplasma iowae, Mycoplasma meleagridis and Mycoplasma synoviae were therefore evaluated for use in birds of prey. The specificities of the PCR methods were established using avian and other mycoplasmas and also selected walled bacteria. The sensitivities of the different PCR assays varied between 100 fg and 10 pg DNA. Fifty-three tracheal swabs from healthy captive and free-ranging birds of prey were then investigated using these PCRs, and in no case was an amplicon obtained for M. gallisepticum/M. imitans, M. iowae or M. synoviae. Species-specific primers for M. meleagridis amplified a product from eight birds of prey but restriction enzyme analysis as well as sequencing of PCR products demonstrated these results to be false positives. Alignment studies of the sequenced products with the 16S rRNA gene sequence of various Mycoplasma species in GenBank demonstrated an identity of 91% to M. meleagridis but of 98% to Mycoplasma buteonis or Mycoplasma gallopavonis. Isolation and attempted identification of these mycoplasmas suggested it may be a previously unrecognized species.

  1. 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...

  2. Structures of the Toxoplasma gliding motility adhesin

    PubMed Central

    Song, Gaojie; Springer, Timothy A.

    2014-01-01

    Micronemal protein 2 (MIC2) is the key adhesin that supports gliding motility and host cell invasion by Toxoplasma gondii. With a von Willebrand factor A (VWA) domain and six thrombospondin repeat domains (TSR1–6) in its ectodomain, MIC2 connects to the parasite actomyosin system through its cytoplasmic tail. MIC2-associated protein (M2AP) binds noncovalently to the MIC2 ectodomain. MIC2 and M2AP are stored in micronemes as proforms. We find that the MIC2–M2AP ectodomain complex is a highly elongated 1:1 monomer with M2AP bound to the TSR6 domain. Crystal structures of N-terminal fragments containing the VWA and TSR1 domains for proMIC2 and MIC2 reveal a closed conformation of the VWA domain and how it associates with the TSR1 domain. A long, proline-rich, disulfide-bonded pigtail loop in TSR1 overlaps the VWA domain. Mannose α-C-linked to Trp-276 in TSR1 has an unusual 1C4 chair conformation. The MIC2 VWA domain includes a mobile α5-helix and a 22-residue disordered region containing two disulfide bonds in place of an α6-helix. A hydrophobic residue in the prodomain binds to a pocket adjacent to the α7-helix that pistons in opening of the VWA domain to a putative high-affinity state. PMID:24639528

  3. Mycoplasma infections of plants.

    PubMed

    Bove, J M

    1981-07-01

    Plants can be infected by two types of wall-less procaryotes, spiroplasmas and mycoplasma-like organisms (MLO), both located intracellularly in the phloem tissues of affected plants. Spiroplasmas have been cultured, characterized and shown to be true members of the class Mollicutes. MLO have not yet been cultured or characterized; they are thought to be mycoplasma-like on the basis of their ultrastructure as seen in situ, their sensitivity to tetracycline and resistance to penicillin. Mycoplasmas can also be found on the surface of plants. These extracellularly located organisms are members of the following genera: Spiroplasma. Mycoplasma and Acholeplasma. The presence of such surface mycoplasmas must not be overlooked when attempts to culture MLO from affected plants are undertaken. Sensitive serological techniques such as the enzyme-linked immunosorbent assay (ELISA) can successfully be used to compare the MLO located in the phloem of affected plants with those eventually cultured from the same plants. In California and Morocco periwinkles naturally infected with both Spiroplasma citri and MLO have been reported. With such doubly infected plants, the symptom expression has been that characteristic of the MLO disease (phyllody or stolbur), not that given by S. citri. Only S. citri can be cultured from such plants, but this does not indicate that S. citri is the causal agent of the disease expressed by the plant. In California many nonrutaceous plants have been found to be infected with S. citri. Stubborn affected citrus trees represent an important reservoir of S. citri, and Circulifer tenellus is an active leafhopper vector of S. citri. Hence, it is not surprising that in California MLO-infected fruit trees could also become infected with S. citri but it would not mean that S. citri is the causal agent of the disease. Criteria are discussed that are helpful in distinguishing between MLO infections and S. citri infections.

  4. Intestinal mycoplasma in Crohn's disease.

    PubMed

    Roediger, W E W

    2004-01-01

    Intestinal diversion with reconnection in active Crohn's disease (CD) indicates that luminal contents or bacteria contribute to the formation of CD lesions. Fluorescent staining for mycoplasma in freshly resected Crohn's tissue and electron microscopy reveal intracellular organisms akin to mycoplasma. Historically, tissue culture of CD has shown mycoplasma described as contaminants. Mycoplasma are surface epithelial parasites requiring exogenous cholesterol for membrane stability and cell entry. PCR of intestinal tissue has shown Mycoplasma pneumoniae to be detectable more significantly in CD. Oral M. iowae in experimental poultry localizes to the distal small bowel and colon. Hypothetically, lipopeptides of mycoplasmal membranes are proposed to cause chronicity and stronger immune responses than by other bacteria. 'Intestinal' mycoplasmas, from a number of observations, deserve consideration as organisms mediating inflammation of acute and chronic CD.

  5. Gliding resistance and modifications of gliding surface of tendon: clinical perspectives.

    PubMed

    Amadio, Peter C

    2013-05-01

    The smooth gliding of the normal human digital flexor is maintained by synovial fluid lubrication and lubricants bound to the tendon surface. This system can be disrupted by degenerative conditions such as trigger finger, or by trauma. The resistance to tendon gliding after surgical repair of the lacerated digital flexor tendon relates to location of suture knots, exposure of suture materials, and type of surgical repair and materials. Restoration of a functioning gliding surface after injury can be helped by using low-friction, high-strength suture designs, therapy that enables gliding, and the addition of lubricants to the tendon surface.

  6. 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.

  7. 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.

  8. A rotary motor drives Flavobacterium gliding.

    PubMed

    Shrivastava, Abhishek; Lele, Pushkar P; Berg, Howard C

    2015-02-02

    Cells of Flavobacterium johnsoniae, a rod-shaped bacterium devoid of pili or flagella, glide over glass at speeds of 2-4 μm/s [1]. Gliding is powered by a protonmotive force [2], but the machinery required for this motion is not known. Usually, cells move along straight paths, but sometimes they exhibit a reciprocal motion, attach near one pole and flip end over end, or rotate. This behavior is similar to that of a Cytophaga species described earlier [3]. Development of genetic tools for F. johnsoniae led to discovery of proteins involved in gliding [4]. These include the surface adhesin SprB that forms filaments about 160 nm long by 6 nm in diameter, which, when labeled with a fluorescent antibody [2] or a latex bead [5], are seen to move longitudinally down the length of a cell, occasionally shifting positions to the right or the left. Evidently, interaction of these filaments with a surface produces gliding. To learn more about the gliding motor, we sheared cells to reduce the number and size of SprB filaments and tethered cells to glass by adding anti-SprB antibody. Cells spun about fixed points, mostly counterclockwise, rotating at speeds of 1 Hz or more. The torques required to sustain such speeds were large, comparable to those generated by the flagellar rotary motor. However, we found that a gliding motor runs at constant speed rather than at constant torque. Now, there are three rotary motors powered by protonmotive force: the bacterial flagellar motor, the Fo ATP synthase, and the gliding motor.

  9. 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

  10. Polymer confinement and bacterial gliding motility

    NASA Astrophysics Data System (ADS)

    Jeon, J.; Dobrynin, A. V.

    2005-07-01

    Cyanobacteria and myxobacteria use slime secretion for gliding motility over surfaces. The slime is produced by the nozzle-like pores located on the bacteria surface. To understand the mechanism of gliding motion and its relation to slime polymerization, we have performed molecular dynamics simulations of a molecular nozzle with growing inside polymer chains. These simulations show that the compression of polymer chains inside the nozzle is a driving force for propulsion. There is a linear relationship between the average nozzle velocity and the chain polymerization rate with a proportionality coefficient dependent on the geometric characteristics of the nozzle such as its length and friction coefficient. This minimal model of the molecular engine was used to explain the gliding motion of bacteria over surfaces.

  11. 14 CFR 23.71 - Glide: Single-engine airplanes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical miles, per 1,000 feet of altitude lost in a glide, and the speed necessary to achieve this must be...

  12. ILS Glide Slope Performance Prediction. Volume B

    DTIC Science & Technology

    1974-09-01

    AD-A009 432 ILS GLIDE SLOPE PERFORMANCE PREDICTION. VOLUME B S . Morin, et al Transportation Systems Center Ptep~ared for: Federal Aviation...Administration September 1974 . S . KPM UE=1 OF UommE Best Available Copy Teemicl e D Osaoeetai1. P.e 1. N.. 12. G.o.....t Accosaten He. 3. £ai oae t s Coe&g We...FAA-RD- 74 157. B I ~J ? 3 - 4. Tale 4d Sbtl. S . Euem Dt* September 1974 ILS GLIDE SLOPE PERFORMANCE PREDICTION . 1974.o.wift C* VOLUME B

  13. Systematic Structural Analyses of Attachment Organelle in Mycoplasma pneumoniae.

    PubMed

    Nakane, Daisuke; Kenri, Tsuyoshi; Matsuo, Lisa; Miyata, Makoto

    2015-12-01

    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.

  14. 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

  15. Mycoplasma polysaccharide protects against complement

    PubMed Central

    Bolland, Jeffrey R.; Simmons, Warren L.; Daubenspeck, James M.

    2012-01-01

    Although they lack a cell wall, mycoplasmas do possess a glycocalyx. The interactions between the glycocalyx, mycoplasmal surface proteins and host complement were explored using the murine pathogen Mycoplasma pulmonis as a model. It was previously shown that the length of the tandem repeat region of the surface lipoprotein Vsa is associated with susceptibility to complement-mediated killing. Cells producing a long Vsa containing about 40 repeats are resistant to complement, whereas strains that produce a short Vsa of five or fewer repeats are susceptible. We show here that the length of the Vsa protein modulates the affinity of the M. pulmonis EPS-I polysaccharide for the mycoplasma cell surface, with more EPS-I being associated with mycoplasmas producing a short Vsa protein. An examination of mutants that lack EPS-I revealed that planktonic mycoplasmas were highly susceptible to complement killing even when the Vsa protein was long, demonstrating that both EPS-I and Vsa length contribute to resistance. In contrast, the mycoplasmas were resistant to complement even in the absence of EPS-I when the cells were encased in a biofilm. PMID:22504437

  16. 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.

  17. 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.

  18. Global dynamics of non-equilibrium gliding in animals.

    PubMed

    Yeaton, Isaac J; Socha, John J; Ross, Shane D

    2017-03-17

    Gliding flight-moving horizontally downward through the air without power-has evolved in a broad diversity of taxa and serves numerous ecologically relevant functions such as predator escape, expanding foraging locations, and finding mates, and has been suggested as an evolutionary pathway to powered flight. Historically, gliding has been conceptualized using the idealized conditions of equilibrium, in which the net aerodynamic force on the glider balances its weight. While this assumption is appealing for its simplicity, recent studies of glide trajectories have shown that equilibrium gliding is not the norm for most species. Furthermore, equilibrium theory neglects the aerodynamic differences between species, as well as how a glider can modify its glide path using control. To investigate non-equilibrium glide behavior, we developed a reduced-order model of gliding that accounts for self-similarity in the equations of motion, such that the lift and drag characteristics alone determine the glide trajectory. From analysis of velocity polar diagrams of horizontal and vertical velocity from several gliding species, we find that pitch angle, the angle between the horizontal and chord line, is a control parameter that can be exploited to modulate glide angle and glide speed. Varying pitch results in changing locations of equilibrium glide configurations in the velocity polar diagram that govern passive glide dynamics. Such analyses provide a new mechanism of interspecies comparison and tools to understand experimentally-measured kinematics data and theory. In addition, this analysis suggests that the lift and drag characteristics of aerial and aquatic autonomous gliders can be engineered to passively alter glide trajectories with minimal control effort.

  19. 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.

  20. GLIDES – Efficient Energy Storage from ORNL

    SciTech Connect

    Momen, Ayyoub M.; Abu-Heiba, Ahmad; Odukomaiya, Wale; Akinina, Alla

    2016-03-01

    The research shown in this video features the GLIDES (Ground-Level Integrated Diverse Energy Storage) project, which has been under development at Oak Ridge National Laboratory (ORNL) since 2013. GLIDES can store energy via combined inputs of electricity and heat, and deliver dispatchable electricity. Supported by ORNL’s Laboratory Director’s Research and Development (LDRD) fund, this energy storage system is low-cost, and hybridizes compressed air and pumped-hydro approaches to allow for storage of intermittent renewable energy at high efficiency. A U.S. patent application for this novel energy storage concept has been submitted, and research findings suggest it has the potential to be a flexible, low-cost, scalable, high-efficiency option for energy storage, especially useful in residential and commercial buildings.

  1. 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.

  2. Polymer confinement and bacterial gliding motility

    NASA Astrophysics Data System (ADS)

    Jeon, Junhwan; Dobrynin, Andrey

    2006-03-01

    Cyanobacteria and myxobacteria use slime secretion for gliding motility over surfaces. In cyanobacteria the slime is extruded from the nozzle-like pores of 14-16 nm outer diameter and approximately 7nm inner diameter located near the septa that separate the cells of a filament. The pores are inclined at an angle of 30-40 degrees relative to the cell axes, and are oppositely directed on both sides of the septum. Such pore orientation provides directionality for the slime secretion as well as cell motion. To understand the mechanism of gliding motion and its relation to slime polymerization, we have performed molecular dynamics simulations of a molecular nozzle with growing inside polymer chains. These simulations show that the compression of polymer chains inside the nozzle is a driving force for its propulsion. There is a linear relationship between the average nozzle velocity and the chain polymerization rate with a proportionality coefficient dependent on the geometric characteristics of the nozzle such as its length and friction coefficient. This minimal model of the molecular engine was used to explain the gliding motion of cyanobacteria and myxobacteria over surfaces.

  3. Mycoplasmas in diseases of humans.

    PubMed Central

    Embree, J E; Embil, J A

    1980-01-01

    The roles of Mycoplasma pneumoniae, M. hominis and Ureaplasma urealyticum in diseases of humans are currently under investigation. M. pneumoniae, which causes primary atypical pneumonia, is a well established pathogen of the respiratory tract. Complications of infection by this organism are also being recognized; they include disorders of the hematopoietic, cardiovascular, central nervous, musculoskeletal, cutaneous and gastrointestinal systems. The roles of the genital mycoplasmas M. hominis and U. urealyticum are controversial but may include infections of the genitourinary tract and in pregnancy as well as diseases of the newborn, such as neonatal pneumonia and meningitis. In this review atypical pneumonia due to M. pneumoniae is described and the role of mycoplasmas in other diseases is discussed. Images FIG. 1A FIG. 1B FIG. 2 PMID:6790148

  4. Mycoplasma infections in small ruminants.

    PubMed

    Ruffin, D C

    2001-07-01

    Mycoplasmas have complex mechanisms of antigenic variation that allow them to evade the immune system. These organisms cause a variety of clinical syndromes that can have a significant economic effect on small ruminant production. The syndromes range from acute septicemia and death to chronic infection resulting in decreased production. Recent research findings have shed light on the means by which these organisms evade the host immune response and cause or contribute to the development of disease in the host. This article provides a review of the pathogenesis, clinical signs, and treatment options for common disease syndromes involving Mycoplasma spp. in small ruminants.

  5. Pathobiology of Mycoplasma suis.

    PubMed

    Hoelzle, Ludwig E; Zeder, Michael; Felder, Kathrin M; Hoelzle, Katharina

    2014-10-01

    Mycoplasma suis is an uncultivable bacterium lacking a cell wall that attaches to and may invade the red blood cells of pigs. M. suis infections occur worldwide and cause the pig industry serious economic losses due to the disease known as infectious anaemia of pigs or, historically, porcine eperythrozoonosis. Infectious anaemia of pigs is characterised predominantly by acute haemolytic or chronic anaemia, along with non-specific manifestations, such as growth retardation in feeder pigs and poor reproductive performance in sows. The fastidious nature of M. suis, as well as the lack of an in vitro cultivation system, has hampered the understanding of the biology and pathogenicity of this organism. Pathogenetic mechanisms of M. suis include direct destruction of red blood cells by adhesion, invasion, nutrient scavenging, immune-mediated lysis and eryptosis, as well as endothelial targeting. Recently published genome sequences, in combination with proteome analyses, have generated new insights into the pathogenicity of M. suis. The present review combines these data with the knowledge provided by experimental M. suis infections.

  6. 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

  7. 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

    2016-07-07

    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.

  8. Aerodynamics of gliding flight in common swifts.

    PubMed

    Henningsson, P; Hedenström, A

    2011-02-01

    Gliding flight performance and wake topology of a common swift (Apus apus L.) were examined in a wind tunnel at speeds between 7 and 11 m s(-1). The tunnel was tilted to simulate descending flight at different sink speeds. The swift varied its wingspan, wing area and tail span over the speed range. Wingspan decreased linearly with speed, whereas tail span decreased in a nonlinear manner. For each airspeed, the minimum glide angle was found. The corresponding sink speeds showed a curvilinear relationship with airspeed, with a minimum sink speed at 8.1 m s(-1) and a speed of best glide at 9.4 m s(-1). Lift-to-drag ratio was calculated for each airspeed and tilt angle combinations and the maximum for each speed showed a curvilinear relationship with airspeed, with a maximum of 12.5 at an airspeed of 9.5 m s(-1). Wake was sampled in the transverse plane using stereo digital particle image velocimetry (DPIV). The main structures of the wake were a pair of trailing wingtip vortices and a pair of trailing tail vortices. Circulation of these was measured and a model was constructed that showed good weight support. Parasite drag was estimated from the wake defect measured in the wake behind the body. Parasite drag coefficient ranged from 0.30 to 0.22 over the range of airspeeds. Induced drag was calculated and used to estimate profile drag coefficient, which was found to be in the same range as that previously measured on a Harris' hawk.

  9. Activity of moxifloxacin against the urogenital mycoplasmas Ureaplasma spp., Mycoplasma hominis and Mycoplasma genitalium and Chlamydia trachomatis.

    PubMed

    Bébéar, C M; de Barbeyrac, B; Pereyre, S; Renaudin, H; Clerc, M; Bébéar, C

    2008-08-01

    The activity of moxifloxacin was compared with that of other antimicrobial agents against 54 strains of Ureaplasma spp., 54 strains of Mycoplasma hominis, 14 strains of Mycoplasma genitalium, and 44 strains of Chlamydia trachomatis. Moxifloxacin inhibited 90% of all isolates at a concentration mycoplasmas. Moxifloxacin killed the 30 mycoplasma isolates tested at a concentration

  10. Relationships between glide efficiency and swimmers' size and shape characteristics.

    PubMed

    Naemi, Roozbeh; Psycharakis, Stelios G; McCabe, Carla; Connaboy, Chris; Sanders, Ross H

    2012-08-01

    Glide efficiency, the ability of a body to minimize deceleration over the glide, can change with variations in the body's size and shape. The purpose of this study was to investigate the relationships between glide efficiency and the size and shape characteristics of swimmers. Eight male and eight female swimmers performed a series of horizontal glides at a depth of 70 cm below the surface. Glide efficiency parameters were calculated for velocities ranging from 1.4 to 1.6 m/s for female swimmers (and at the Reynolds number of 3.5 million) and from 1.6 to 1.8 m/s for male swimmers (and at the Reynolds number of 4.5 million). Several morphological indices were calculated to account for the shape characteristics, with the use of a photogrammetric method. Relationships between the variables of interest were explored with correlations, while repeated-measures ANOVA was used to assess within-group differences between different velocities for each gender group. Glide efficiency of swimmers increased when velocity decreased. Some morphological indices and postural angles showed a significant correlation with glide efficiency. The glide coefficient was significantly correlated to the chest to waist taper index for both gender groups. For the male group, the glide coefficient correlated significantly to the fineness ratio of upper body, the chest to hip cross-section. For the female group the glide coefficient had a significant correlation with the waist to hip taper index. The findings suggested that gliding efficiency was more dependent on shape characteristics and appropriate postural angles rather than being dependent on size characteristics.

  11. Prevention and Detection of Mycoplasma Contamination in Cell Culture

    PubMed Central

    Nikfarjam, Laleh; Farzaneh, Parvaneh

    2012-01-01

    One of the main problems in cell culture is mycoplasma infection. It can extensively affect cell physiology and metabolism. As the applications of cell culture increase in research, industrial production and cell therapy, more concerns about mycoplasma contamination and detection will arise. This review will provide valuable information about: 1. the ways in which cells are contaminated and the frequency and source of mycoplasma species in cell culture; 2. the ways to prevent mycoplasma contamination in cell culture; 3. the importance of mycoplasma tests in cell culture; 4. different methods to identify mycoplasma contamination; 5. the consequences of mycoplasma contamination in cell culture and 6. available methods to eliminate mycoplasma contamination. Awareness about the sources of mycoplasma and pursuing aseptic techniques in cell culture along with reliable detection methods of mycoplasma contamination can provide an appropriate situation to prevent mycoplasma contamination in cell culture. PMID:23508237

  12. Mycoplasma infection of ducks and geese.

    PubMed

    Stipkovits, L; Szathmary, S

    2012-11-01

    Production of ducks and geese in certain parts of the world is very important. Mycoplasma diseases cause significant losses to the duck and goose industry. This review summarizes the epidemiological, clinical, and pathomorphological characteristics of mycoplasma diseases of ducks and geese and the involvement of the various mycoplasma species in their pathogenesis. The role of mycoplasma infections in the development of clinical signs, pathological lesions, and mortality of challenged birds is demonstrated in challenge experiments. Transmission of mycoplasma in the ovary and eggs resulting in the reduction of egg production and an increase of embryo mortality has been shown in challenge experiments as well as in field studies. The susceptibility of many mycoplasma isolates of the most important mycoplasma species of duck and goose origin were tested and showed relatively high average minimum inhibitory concentrations of lincomycin, tilosin, oxytetracycline, chlortetracycline, and enrofloxacin but not for tiamulin. The successful treatment of mycoplasma infections with antibiotics in ducks and geese should be selected based on the minimum inhibitory concentration values against the mycoplasmas isolated from the flock.

  13. 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...

  14. 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...

  15. How swifts control their glide performance with morphing wings.

    PubMed

    Lentink, D; Müller, U K; Stamhuis, E J; de Kat, R; van Gestel, W; Veldhuis, L L M; Henningsson, P; Hedenström, A; Videler, J J; van Leeuwen, J L

    2007-04-26

    Gliding birds continually change the shape and size of their wings, presumably to exploit the profound effect of wing morphology on aerodynamic performance. That birds should adjust wing sweep to suit glide speed has been predicted qualitatively by analytical glide models, which extrapolated the wing's performance envelope from aerodynamic theory. Here we describe the aerodynamic and structural performance of actual swift wings, as measured in a wind tunnel, and on this basis build a semi-empirical glide model. By measuring inside and outside swifts' behavioural envelope, we show that choosing the most suitable sweep can halve sink speed or triple turning rate. Extended wings are superior for slow glides and turns; swept wings are superior for fast glides and turns. This superiority is due to better aerodynamic performance-with the exception of fast turns. Swept wings are less effective at generating lift while turning at high speeds, but can bear the extreme loads. Finally, our glide model predicts that cost-effective gliding occurs at speeds of 8-10 m s(-1), whereas agility-related figures of merit peak at 15-25 m s(-1). In fact, swifts spend the night ('roost') in flight at 8-10 m s(-1) (ref. 11), thus our model can explain this choice for a resting behaviour. Morphing not only adjusts birds' wing performance to the task at hand, but could also control the flight of future aircraft.

  16. 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 Section 23.71 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical...

  17. 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 Section 23.71 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Glide: Single-engine airplanes. The maximum horizontal distance traveled in still air, in nautical...

  18. 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

  19. 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).

  20. 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... 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...

  1. 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...

  2. 21 CFR 610.30 - Test for Mycoplasma.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 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...

  3. 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... 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...

  4. 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

  5. Bilateral optic papillitis following mycoplasma pneumoniae pneumonia.

    PubMed

    Milla, E; Zografos, L; Piguet, B

    1998-01-01

    Mycoplasma pneumoniae is an atypical bacterium that can cause a great variety of respiratory infections and be responsible for ocular involvement such as conjunctivitis, anterior uveitis and very rarely optic neuropathy. We report herein an additional case of bilateral optic disc swelling with profound visual loss following Mycoplasma pneumoniae pneumonia and review the world literature on the ocular manifestations associated with this pathogen.

  6. Submasseteric abscess caused by Mycoplasma salivarium infection.

    PubMed

    Grisold, Andrea J; Hoenigl, Martin; Leitner, Eva; Jakse, Klaus; Feierl, Gebhard; Raggam, Reinhard B; Marth, Egon

    2008-11-01

    Mycoplasma salivarium preferentially resides in the human oral cavity. Unlike other Mycoplasma species, M. salivarium has not been regarded as a pathogen, although one case of M. salivarium-caused arthritis in a patient with hypogammaglobulinemia has been reported. We describe the first case of submasseteric abscess caused by M. salivarium.

  7. 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.

  8. One test microbial diagnostic microarray for identification of Mycoplasma mycoides subsp. mycoides and other Mycoplasma species.

    PubMed

    Tonelli, A; Sacchini, F; Krasteva, I; Zilli, K; Scacchia, M; Beaurepaire, C; Nantel, A; Pini, A

    2012-11-01

    The present study describes the use of microarray technology for rapid identification and differentiation of Mycoplasma mycoides subsp. mycoides from other mycoplasmas that may be pathogenic to ruminants, including those of the Mycoplasma mycoides cluster, genetically and antigenically strictly correlated with Mycoplasma mycoides subsp. mycoides. A microarray containing genetic sequences of 55 different bacterial species from Acholeplasma, Mycoplasma, Spiroplasma and Ureaplasma genera was constructed. Sequences to genes of interest were collected in FASTA format from NCBI. The collected sequences were processed with OligoPicker software. Oligonucleotides were then checked for their selectivity with BLAST searches in GenBank. The microarray was tested with ATCC/NCTC strains of Mycoplasma spp. of veterinary importance in ruminants including Mycoplasma belonging to the mycoides cluster as well as Mycoplasma mycoides subsp. mycoides and Mycoplasma mycoides subsp. capri field strains. The results showed that but one ATCC/NCTC reference strains hybridized with their species-specific sequences showed a profile/signature different and distinct from each other. The heat-map of the hybridization results for the nine genes interrogated for Mycoplasma mycoides subsp. mycoides demonstrated that the reference strain Mycoplasma mycoides subsp mycoides PG1 was positive for all of the gene sequences spotted on the microarray. CBPP field, vaccine and reference strains were all typed to be M. mycoides subsp. mycoides, and seven of the nine strains gave positive hybridization results for all of the nine genes. Two Italian strains were negative for some of the genes. Comparison with non-Mycoplasma mycoides subsp. mycoides reference strains showed some positive signals or considerable homology to Mycoplasma mycoides subsp. mycoides genes. As expected, some correlations were observed between the strictly genetically and antigenically correlated Mycoplasma mycoides subsp. mycoides and

  9. Eradication of Mycoplasma contaminations from cell cultures.

    PubMed

    Uphoff, Cord C; Drexler, Hans G

    2014-04-14

    Mycoplasma contaminations have a multitude of effects on cultured cell lines that may influence the results of experiments or pollute bioactive substances isolated from the eukaryotic cells. The elimination of mycoplasma contaminations from cell cultures with antibiotics has been proven to be a practical alternative to discarding and re-establishing important or irreplaceable cell lines. Different fluoroquinolones, tetracyclins, pleuromutilins, and macrolides shown to have strong anti-mycoplasma properties are employed for the decontamination. These antibiotics are applied as single treatments, as combination treatment of two antibiotics in parallel or successively, or in combination with a surface-active peptide to enhance the action of the antibiotic. The protocols in this unit allow eradication of mycoplasmas, prevention of the development of resistant mycoplasma strains, and potential cure of heavily contaminated and damaged cells. Consistent and permanent alterations to eukaryotic cells attributable to the treatment have not been demonstrated.

  10. 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.

  11. Detection of Mycoplasma canadense and Mycoplasma californicum in dairy cattle from Argentina.

    PubMed

    Tamiozzo, Pablo J; Estanguet, Abel A; Maito, Julia; Tirante, Liliana; Pol, Martin; Giraudo, José A

    2014-01-01

    Different species of Mycoplasma can affect bovine cattle, causing several diseases. PCR sequencing and further analysis of the 16S-23S rRNA ITS region have shown a significant interspecies variability among Mollicutes. Sixteen suspected isolates of Mycoplasma spp. obtained from milk samples from dairy herds were amplified (16S-23S rRNA ITS region). Fourteen out of those 16 suspected Mycoplasma spp. isolates were PCR-positive. To confirm the identity of Mycoplasma bovis, these 14 isolates were tested by another species-specific PCR. Seven of the isolates rendered a positive result. The products of 16S-23S rRNA ITS PCR from one isolate that was identified as M. bovis and from two other isolates, identified as non- M. bovis were randomly selected, sequenced and analyzed. The three sequences (A, B and C) showed 100% similarity with M. bovis, Mycoplasma canadense and Mycoplasma californicum respectively.

  12. 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.

  13. 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.

  14. Sedimentation counting and morphology of Mycoplasma.

    PubMed

    Clark, H W

    1965-11-01

    Clark, Harold W. (The George Washington University School of Medicine, Washington, D.C.). Sedimentation counting and morphology of Mycoplasma. J. Bacteriol. 90:1373-1386. 1965.-The sedimentation technique for counting viral particles was applied to the quantitation and morphological identification of Mycoplasma in broth cultures. Mycoplasma, apparently in their native form, firmly adhered to the surface, when sedimented on glass cover slips or onto electron microscope grids. The sedimented cover slip preparations stained with crystal violet could be readily counted in the light microscope. The cultures sedimented onto electron microscope grids were readily counted at low magnification and provided excellent preparations for morphological examination at higher magnifications. It was found that air-dried Mycoplasma particles were enlarged considerably because of excessive flattening. Fixation of sedimented Mycoplasma particles in diluted OsO(4) prior to air drying yielded a more realistic morphology, with various sizes and shapes in the stages of the growth cycle exhibited. A new technique of differentially staining Mycoplasma colonies on agar plates was developed to facilitate the quantitation of viable colony-forming units for comparison with total counts. The use of plastic or Parafilm gaskets for dry mounting was developed to facilitate the handling and examination of the stained cover slip preparations. The results of this investigation indicated that the growth cycle of some Mycoplasma species includes a stage of hexadic fission with the cleavage of minimal reproductive units (less than 100 mmu) containing a limited deoxyribonucleic acid genetic coding molecule (approximately 4 x 10(6)).

  15. Nonlinear stability and control of gliding vehicles

    NASA Astrophysics Data System (ADS)

    Bhatta, Pradeep

    In this thesis we use nonlinear systems analysis to study dynamics and design control solutions for vehicles subject to hydrodynamic or aerodynamic forcing. Application of energy-based methods for such vehicles is challenging due to the presence of energy-conserving lift and side forces. We study how the lift force determines the geometric structure of vehicle dynamics. A Hamiltonian formulation of the integrable phugoid-mode equations provides a Lyapunov function candidate, which is used throughout the thesis for deriving equilibrium stability results and designing stabilizing control laws. A strong motivation for our work is the emergence of underwater gliders as an important observation platform for oceanography. Underwater gliders rely on buoyancy regulation and internal mass redistribution for motion control. These vehicles are attractive because they are designed to operate autonomously and continuously for several weeks. The results presented in this thesis contribute toward the development of systematic control design procedures for extending the range of provably stable maneuvers of the underwater glider. As the first major contribution we derive conditions for nonlinear stability of longitudinal steady gliding motions using singular perturbation theory. Stability is proved using a composite Lyapunov function, composed of individual Lyapunov functions that prove stability of rotational and translational subsystem equilibria. We use the composite Lyapunov function to design control laws for stabilizing desired relative equilibria in different actuation configurations for the underwater glider. We propose an approximate trajectory tracking method for an aircraft model. Our method uses exponential stability results of controllable steady gliding motions, derived by interpreting the aircraft dynamics as an interconnected system of rotational and translational subsystems. We prove bounded position error for tracking prescribed, straight-line trajectories, and

  16. Illusory continuity without sufficient sound energy to fill a temporal gap: examples of crossing glide tones.

    PubMed

    Kuroda, Tsuyoshi; Nakajima, Yoshitaka; Eguchi, Shuntarou

    2012-10-01

    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 transfer illusion. We found that the subjective continuity-discontinuity of the crossing glides changed as a function of the relative level of the shorter glide to the level of the longer glide. When the relative level was approximately between -9 and +2 dB, listeners perceived the longer glide as continuous and the shorter glide as discontinuous, that is, the gap transfer illusion took place. The glides were perceived veridically below this range, that is, gap transfer did not take place, whereas above this range the longer glide and the shorter glide were both perceived as continuous. The fact that the longer glide could be perceived as continuous even when the crossing shorter glide was 9 dB weaker indicates that the longer glide's subjective continuity cannot be explained within the conventional framework of auditory organization, which assumes reallocation of sound energy from the shorter to the longer glide. The implicated mechanisms are discussed in terms of the temporal configuration of onsets and terminations and the time-frequency distribution of sound energy.

  17. Soaring energetics and glide performance in a moving atmosphere

    PubMed Central

    Reynolds, Kate V.; Thomas, Adrian L. R.

    2016-01-01

    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

  18. Mobilization

    DTIC Science & Technology

    1987-01-01

    istic and romantic emotionalism that typifies this genre. Longino, James C., et al. “A Study of World War Procurement and Industrial Mobilization...States. Harrisburg, PA: Military Service Publishing Co., 1941. CARL 355.22 J72b. Written in rough prose , this World War II era document explains the

  19. Gliding flight in Chrysopelea: turning a snake into a wing.

    PubMed

    Socha, John J

    2011-12-01

    Although many cylindrical animals swim through water, flying snakes of the genus Chrysopelea are the only limbless animals that glide through air. Despite a lack of limbs, these snakes can actively launch by jumping, maintain a stable glide path without obvious control surfaces, maneuver, and safely land without injury. Jumping takeoffs employ vertically looped kinematics that seem to be different than any other behavior in limbless vertebrates, and their presence in a closely related genus suggests that gap-crossing may have been a behavioral precursor to the evolution of gliding in snakes. Change in shape of the body by dorsoventral flattening and high-amplitude aerial undulation comprise two key features of snakes' gliding behavior. As the snake becomes airborne, the body flattens sequentially from head to vent, forming a cross-sectional shape that is roughly triangular, with a flat surface and lateral "lips" that protrude ventrally on each side of the body; these may diminish toward the vent. This shape likely provides the snake with lift coefficients that peak at high angles of attack and gentle stall characteristics. A glide trajectory is initiated with the snake falling at a steep angle. As the snake rotates in the pitch axis, it forms a wide "S" shape and begins undulating in a complex three-dimensional pattern, with the body angled upward relative to the glide path. The head moves side-to-side, sending traveling waves posteriorly toward the tail, while the body (most prominently, the posterior end) oscillates in the vertical axis. These active movements while gliding are substantially different and more dynamic than those used by any other animal glider. As the snake gains forward speed, the glide path becomes less steep, reaching minimally recorded glide angles of 13°. In general, smaller snakes appear to be more proficient gliders. Chrysopelea paradisi can also maneuver and land either on the ground or on vegetation, but these locomotor behaviors have

  20. 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)

  1. Gliding motility in bacteria: insights from studies of Myxococcus xanthus.

    PubMed

    Spormann, A M

    1999-09-01

    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

  2. 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

  3. Survey of plasmids in various mycoplasmas.

    PubMed Central

    Harasawa, R.; Barile, M. F.

    1983-01-01

    Thirty-three strains representing 15 distinct Mycoplasma, Acholeplasma, and Spiroplasma species were examined for the presence of plasmid DNA by agarose gel electrophoresis. The electrophoretic patterns of the DNAs of three strains, Mycoplasma sp. strain 747, Spiroplasma mirum strain SMCA, and M. hominis strain 1257, suggested the presence of a plasmid with molecular weights of approximately 70, 10, and 9 megadaltons, respectively. The functions of these plasmids are currently unknown. Images FIG. 1 PMID:6679154

  4. 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.

  5. 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

  6. Molecular detection of Mycoplasma wenyonii and 'Candidatus Mycoplasma haemobos' in cattle in Hokkaido, Japan.

    PubMed

    Tagawa, Michihito; Matsumoto, Kotaro; Inokuma, Hisashi

    2008-11-25

    Blood samples from 78 cattle were tested for hemoplasma infection using molecular methods. PCR and sequence analysis revealed that 17 cattle were infected with Mycoplasma wenyonii, while 13 were infected with 'Candidatus Mycoplasma haemobos'. Four animals were infected with both species. This is the first study to report hemoplasma species infection among cattle in Japan.

  7. A "hydrokinematic" method of measuring the glide efficiency of a human swimmer.

    PubMed

    Naemi, Roozbeh; Sanders, Ross H

    2008-12-01

    The aim of this study was to develop and test a method of quantifying the glide efficiency, defined as the ability of the body to maintain its velocity over time and to minimize deceleration through a rectilinear glide. The glide efficiency should be determined in a way that accounts for both the inertial and resistive characteristics of the gliding body as well as the instantaneous velocity. A displacement function (parametric curve) was obtained from the equation of motion of the body during a horizontal rectilinear glide. The values of the parameters in the displacement curve that provide the best fit to the displacement-time data of a body during a rectilinear horizontal glide represent the glide factor and the initial velocity of the particular glide interval. The glide factor is a measure of glide efficiency and indicates the ability of the body to minimize deceleration at each corresponding velocity. The glide efficiency depends on the hydrodynamic characteristic of the body, which is influenced by the body's shape as well as by the body's size. To distinguish the effects of size and shape on the glide efficiency, a size-related glide constant and a shape-related glide coefficient were determined as separate entities. The glide factor is the product of these two parameters. The goodness of fit statistics indicated that the representative displacement function found for each glide interval closely represents the real displacement data of a body in a rectilinear horizontal glide. The accuracy of the method was indicated by a relative standard error of calculation of less than 2.5%. Also the method was able to distinguish between subjects in their glide efficiency. It was found that the glide factor increased with decreasing velocity. The glide coefficient also increased with decreasing Reynolds number. The method is sufficiently accurate to distinguish between individual swimmers in terms of their glide efficiency. The separation of glide factor to a size

  8. Genome Sequence of Mycoplasma hyorhinis Isolated from Cell Cultures

    PubMed Central

    Cibulski, Samuel Paulo; Siqueira, Franciele Maboni; Teixeira, Thais Fumaco; Mayer, Fabiana Quoos; Almeida, Luiz Gonzaga

    2016-01-01

    Mycoplasmas are major contaminants of mammalian cell cultures. Here, the complete genome sequence of Mycoplasma hyorhinis recovered from Madin-Darby bovine kidney (MDBK) cells is reported. PMID:27738034

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

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... serum. Additionally, some of these reagents consist of Mycoplasma spp. antisera conjugated with a.... The identification aids in the diagnosis of disease caused by bacteria belonging to the genus Mycoplasma and provides epidemiological information on diseases caused by these microorganisms....

  10. Gliding flight in a jackdaw: a wind tunnel study.

    PubMed

    Rosén, M; Hedenström, A

    2001-03-01

    We examined the gliding flight performance of a jackdaw Corvus monedula in a wind tunnel. The jackdaw was able to glide steadily at speeds between 6 and 11 m s(-1). The bird changed its wingspan and wing area over this speed range, and we measured the so-called glide super-polar, which is the envelope of fixed-wing glide polars over a range of forward speeds and sinking speeds. The glide super-polar was an inverted U-shape with a minimum sinking speed (V(ms)) at 7.4 m s(-1) and a speed for best glide (V(bg)) at 8.3 m s(-)). At the minimum sinking speed, the associated vertical sinking speed was 0.62 m s(-1). The relationship between the ratio of lift to drag (L:D) and airspeed showed an inverted U-shape with a maximum of 12.6 at 8.5 m s(-1). Wingspan decreased linearly with speed over the whole speed range investigated. The tail was spread extensively at low and moderate speeds; at speeds between 6 and 9 m s(-1), the tail area decreased linearly with speed, and at speeds above 9 m s(-1) the tail was fully furled. Reynolds number calculated with the mean chord as the reference length ranged from 38 000 to 76 000 over the speed range 6-11 m s(-1). Comparisons of the jackdaw flight performance were made with existing theory of gliding flight. We also re-analysed data on span ratios with respect to speed in two other bird species previously studied in wind tunnels. These data indicate that an equation for calculating the span ratio, which minimises the sum of induced and profile drag, does not predict the actual span ratios observed in these birds. We derive an alternative equation on the basis of the observed span ratios for calculating wingspan and wing area with respect to forward speed in gliding birds from information about body mass, maximum wingspan, maximum wing area and maximum coefficient of lift. These alternative equations can be used in combination with any model of gliding flight where wing area and wingspan are considered to calculate sinking rate with

  11. 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.

  12. 9 CFR 113.408 - Avian mycoplasma antigen.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ion concentration shall be determined with a pH meter which has been standardized with a pH buffer... with five Mycoplasma gallisepticum antiserums (chicken origin); Mycoplasma Meleagridis Antigen shall be examined for cross-agglutination with five Mycoplasma gallisepticum antiserums (turkey origin) and...

  13. 9 CFR 113.408 - Avian mycoplasma antigen.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ion concentration shall be determined with a pH meter which has been standardized with a pH buffer... with five Mycoplasma gallisepticum antiserums (chicken origin); Mycoplasma Meleagridis Antigen shall be examined for cross-agglutination with five Mycoplasma gallisepticum antiserums (turkey origin) and...

  14. 9 CFR 113.408 - Avian mycoplasma antigen.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ion concentration shall be determined with a pH meter which has been standardized with a pH buffer... with five Mycoplasma gallisepticum antiserums (chicken origin); Mycoplasma Meleagridis Antigen shall be examined for cross-agglutination with five Mycoplasma gallisepticum antiserums (turkey origin) and...

  15. 9 CFR 113.408 - Avian mycoplasma antigen.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ion concentration shall be determined with a pH meter which has been standardized with a pH buffer... with five Mycoplasma gallisepticum antiserums (chicken origin); Mycoplasma Meleagridis Antigen shall be examined for cross-agglutination with five Mycoplasma gallisepticum antiserums (turkey origin) and...

  16. 9 CFR 113.408 - Avian mycoplasma antigen.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ion concentration shall be determined with a pH meter which has been standardized with a pH buffer... with five Mycoplasma gallisepticum antiserums (chicken origin); Mycoplasma Meleagridis Antigen shall be examined for cross-agglutination with five Mycoplasma gallisepticum antiserums (turkey origin) and...

  17. 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.

  18. 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

  19. 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.

  20. Ubiquity of quantum zero-point fluctuations in dislocation glide

    NASA Astrophysics Data System (ADS)

    Landeiro Dos Reis, Marie; Choudhury, Anshuman; Proville, Laurent

    2017-03-01

    Modeling the dislocation glide through atomic scale simulations in Al, Cu, and Ni and in solid solution alloys Al(Mg) and Cu(Ag), we show that in the course of the plastic deformation the variation of the crystal zero-point energy (ZPE) and the dislocation potential energy barriers are of opposite sign. The multiplicity of situations where we have observed the same trend allows us to conclude that quantum fluctuations, giving rise to the crystal ZPE, make easier the dislocation glide in most materials, even those constituted of atoms heavier than H and He.

  1. Genes Found Essential in Other Mycoplasmas Are Dispensable in Mycoplasma bovis

    PubMed Central

    Sharma, Shukriti; Markham, Philip F.; Browning, Glenn F.

    2014-01-01

    Mycoplasmas are regarded to be useful models for studying the minimum genetic complement required for independent survival of an organism. Mycoplasma bovis is a globally distributed pathogen causing pneumonia, mastitis, arthritis, otitis media and reproductive tract disease, and genome sequences of three strains, the type strain PG45 and two strains isolated in China, have been published. In this study, several Tn4001 based transposon constructs were generated and used to create a M. bovis PG45 insertional mutant library. Direct genome sequencing of 319 independent insertions detected disruptions in 129 genes in M. bovis, 48 of which had homologues in Mycoplasma mycoides subspecies mycoides SC and 99 of which had homologues in Mycoplasma agalactiae. Sixteen genes found to be essential in previous studies on other mycoplasma species were found to be dispensable. Five of these genes have previously been predicted to be part of the core set of 153 essential genes in mycoplasmas. Thus this study has extended the list of non-essential genes of mycoplasmas from that previously generated by studies in other species. PMID:24897538

  2. 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

  3. 14 CFR 121.360 - Ground proximity warning-glide slope deviation alerting system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Ground proximity warning-glide slope... Equipment Requirements § 121.360 Ground proximity warning-glide slope deviation alerting system. (a) No... turbine-powered airplane unless it is equipped with a ground proximity warning/glide slope...

  4. 14 CFR 121.360 - Ground proximity warning-glide slope deviation alerting system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Ground proximity warning-glide slope... Equipment Requirements § 121.360 Ground proximity warning-glide slope deviation alerting system. (a) No... turbine-powered airplane unless it is equipped with a ground proximity warning/glide slope...

  5. 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…

  6. Identification of cross-reactive antigens between Mycoplasma pulmonis and Mycoplasma arthritidis.

    PubMed Central

    Minion, F C; Brown, M B; Cassell, G H

    1984-01-01

    Serological cross-reactivity between Mycoplasma pulmonis and Mycoplasma arthritidis was investigated by enzyme-linked immunosorbent assay, immunoanalysis of electrophoretic blots, and protein A immunoprecipitation reactions. The results demonstrate that one-way cross-reactivity was present in both hyperimmunized and naturally infected rats and that the predominant cross-reactive antigens were M. pulmonis surface proteins. Distinct immunoblot patterns were demonstrated for M. pulmonis and M. arthritidis, allowing differentiation of the two species. The response to M. arthritidis antigens during natural infections differed greatly from that during hyperimmunization. Evidence suggested that nonprotein antigens were major determinants eliciting the antibody response to this mycoplasma. Images PMID:6690399

  7. 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.

    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.

  8. Pulse-field electrophoresis indicates full-length Mycoplasma chromosomes range widely in size.

    PubMed Central

    Neimark, H C; Lange, C S

    1990-01-01

    Full-size linear chromosomes were prepared from mycoplasmas by using gamma-irradiation to introduce one (on average) double-strand break in their circular chromosomes. Chromosome sizes were estimated by pulsed-field gel electrophoresis (PFGE) from the mobilities of these full-length molecules relative to DNA size references. Sizes estimated for Ureaplasma urealyticum T960 and 16 Mycoplasma species ranged from 684 kbp (M. hominis) to 1315 kbp (M. iowae). Using this sample, we found no correlation between the mobility of the full-size linear chromosomes and their G + C content. Sizes for A. laidlawii and A. hippikon were within the range expected from renaturation kinetics. PFGE size estimates are in good agreement with sizes determined by other methods, including electron microscopy, an ordered clone library, and summation of restriction fragments. Our estimates also agree with those from renaturation kinetics for both the largest and some of the smallest chromosomes, but in the intermediate size range, renaturation kinetics consistently provides lower values than PFGE or electron microscopy. Our PFGE estimates show that mycoplasma chromosomes span a continual range of sizes, with several intermediate values falling between the previously recognized large and small chromosome size clusters. Images PMID:2216718

  9. Reprint of: Dynamics of discrete screw dislocations on glide directions

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

    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.

  10. 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. 171.267 Section 171.267 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) NAVIGATIONAL FACILITIES NON-FEDERAL NAVIGATION FACILITIES Interim Standard...

  11. The environment and materials for glide reentry vehicles

    NASA Technical Reports Server (NTRS)

    Deutsch, G. C.

    1973-01-01

    The environmental conditions to which a large glide reentry vehicle such as the space shuttle is subjected is discussed. A comparison is made with the state of the art for materials and structures to meet this environmental threat. The options that are available are stressed as are the areas where additional research and development is required.

  12. 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,…

  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. 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.

  15. EXPERIMENTAL INFECTION WITH MYCOPLASMA PNEUMONIAE (EATON'S AGENT)

    PubMed Central

    Dajani, Adnan S.; Clyde, Wallace A.; Denny, Floyd W.

    1965-01-01

    The pathogenesis of Mycoplasma pneumoniae infection was studied in the Syrian hamster with qualitative and quantitative culture methods and special histopathologic techniques. The animals were readily infected with the mycoplasma, which multiplied throughout the respiratory tract. Sensitivity of this experimental host to infection was indicated by the 50 per cent infective dose, which was 10 colony-forming units of the organism. Inoculation consistently resulted in the production of peribronchial pneumonitis which was induced by the mycoplasma. The organisms were visualized in a superficial location in the mucosa of involved bronchi, by means of indirect fluorescent antibody staining and by a modification of the Brown and Brenn technique. The data indicate applicability of the hamster to the study of problems concerned with M. pneumoniae disease which are impractical or impossible to resolve in the human host. PMID:14319403

  16. 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

  17. Sialidase Activity in Mycoplasma synoviae

    PubMed Central

    May, Meghan; Kleven, Stanley H.; Brown, Daniel R.

    2008-01-01

    SUMMARY Eleven strains of the avian pathogen Mycoplasma synoviae were evaluated for the presence of sialidase activity by using the fluorogenic substrate 2′-(4-methylumbelliferyl)-α-D-N-acetylneuraminic acid and the sialidase inhibitor 2-deoxy-2,3-didehydro-N-acetylneuraminic acid. The kinetics of in vitro growth in modified Frey’s medium were also assessed for each strain. Five strains had been isolated from clinically symptomatic chickens, and strains WVU1853T and K3344 have been demonstrated to be capable of reproducing disease in specific pathogen-free chickens. All strains exhibited sialidase activity, although the amount varied 65 fold (P < 0.0001) from 1.3 x 10−7 to 2.0 x 10−9 activity units/colony-forming unit among strains. Strains originally isolated from clinically symptomatic birds had more (P < 0.05) sialidase activity than strains from asymptomatic birds. Strain WVU1853T exhibited the most sialidase activity (P < 0.0001) and grew to the highest culture density (P < 0.0001) among strains, but across strains the rank correlation of growth rate with sialidase activity was not significant. Negligible activity was detected in conditioned culture supernatant fluid. This is the first report of sialidase activity in pathogenic strains of M. synoviae, which suggests a potential enzymatic basis for virulence of the organism. PMID:18251389

  18. Candidatus Mycoplasma haematoparvum and Mycoplasma haemocanis infections in dogs from the United States.

    PubMed

    Compton, S M; Maggi, R G; Breitschwerdt, E B

    2012-12-01

    Mycoplasma haemocanis (Mhc) and Candidatus Mycoplasma haematoparvum (CMhp) have been described in dogs. Historically, microscopic visualization of hemotropic Mycoplasma spp. has occurred most often in immunocompromised or splenectomized dogs. The aim of this study was to determine the Mhc and CMhp prevalences among dogs from the United States. Novel 16S rRNA and RNAseP gene PCR assays were used to amplify hemotropic Mycoplasma species DNA for GenBank sequence alignment. Among the study population, hemoplasma prevalence was 1.3% (7 out of 506), with Mhc and CMhp prevalences of 0.6% and 0.8%, respectively. Two of six CMhp-infected dogs were co-infected with a Bartonella sp., and a third dog was seroreactive to Bartonella henselae antigens. The prevalence of Mhc and CMhp in this study was low; potential blood donors should be screened; and dogs and people can be co-infected with hemoplasma and Bartonella spp.

  19. Mycoplasma feriruminatoris sp. nov., a fast growing Mycoplasma species isolated from wild Caprinae.

    PubMed

    Jores, Joerg; Fischer, Anne; Sirand-Pugnet, Pascal; Thomann, Andreas; Liebler-Tenorio, Elisabeth M; Schnee, Christiane; Santana-Cruz, Ivette; Heller, Martin; Frey, Joachim

    2013-12-01

    Five Mycoplasma strains from wild Caprinae were analyzed: four from Alpine ibex (Capra ibex) which died at the Berlin Zoo between 1993 and 1994, one from a Rocky Mountain goat collected in the USA prior to 1987. These five strains represented a population different from the populations belonging to the 'Mycoplasma mycoides cluster' as tested using multi locus sequence typing, Matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis and DNA-DNA hybridization. Analysis of the 16S rRNA gene (rrs), genomic sequence based in silico as well as laboratory DNA-DNA hybridization, and the analysis of phenotypic traits in particular their exceptionally rapid growth all confirmed that they do not belong to any Mycoplasma species described to date. We therefore suggest these strains represent a novel species, for which we propose the name Mycoplasma feriruminatoris sp. nov. The type strain is G5847(T) (=DSM 26019(T)=NCTC 13622(T)) [corrected].

  20. 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.

  1. 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

  2. Demonstration of neuraminidase activity in Mycoplasma neurolyticum and of neuraminidase proteins in three canine Mycoplasma species.

    PubMed

    Berčič, Rebeka Lucijana; Cizelj, Ivanka; Benčina, Mateja; Narat, Mojca; Bradbury, Janet M; Dovč, Peter; Benčina, Dušan

    2012-03-23

    Neuraminidases are virulence factors in many pathogenic microorganisms. They are present also in some Mycoplasma species that cause disease in birds, dogs and alligators. Thirty-seven Mycoplasma species have been examined previously for neuraminidase (sialidase) activity, whereas many of the species causing disease in man, ruminants, pigs, rodents and other animals have not. In this study neuraminidase enzymatic activity (NEAC) was examined in 45 previously untested Mycoplasma species, including those causing diseases in man, farm animals and laboratory animals. The only species in which NEAC was found was Mycoplasma neurolyticum, specifically, its type strain (Type A(T)) which is capable of inducing neurologic signs in inoculated young mice and rats. The NEAC of washed cells was relatively weak, but it differed even more than 10-fold among cells of cultures derived from individual colonies of M. neurolyticum. A weak NEAC was also detected in the supernatant of the M. neurolyticum broth culture. Canine Mycoplasma spp. with high sialidase activity reported previously, Mycoplasma canis, Mycoplasma cynos and Mycoplasma molare had 100-fold more NEAC than M. neurolyticum, but apparent differences in NEAC levels existed among strains of M. canis and of M. cynos. Zymograms using neuraminidase-specific chromogenic substrate were used to show proteins having NEAC. In M. canis (a field isolate Larissa and the type strain PG14(T)), M. cynos (isolate 896) and M. molare (type strain H542(T)) proteins with NEAC had molecular masses of ∼130kDa, 105kDa and 110kDa, respectively. Identification of these neuraminidases could provide the basis for their molecular characterization.

  3. 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.

  4. 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

  5. Isolation and characterization of unusual Mycoplasma spp. from captive Eurasian Griffon (Gyps fulvus) in Sicily.

    PubMed

    Loria, G R; Ferrantelli, E; Giardina, G; Li Vecchi, L; Sparacino, L; Oliveri, F; McAuliffe, L; Nicholas, R A J

    2008-01-01

    Mycoplasmas have been isolated from birds of prey during clinical examinations, but their significance to the health of raptors is unclear. We report the isolation and characterization of four mycoplasmas found in the upper respiratory tract of four sick Eurasian Griffon (Gyps fulvus) that were housed in a Sicilian rehabilitation center at Ficuzza, near Palermo in Sicily, before reintroduction into the wild. These included Mycoplasma gallinarum, an unidentified mycoplasma highly similar to Mycoplasma glycophilum, and two unidentified mycoplasmas with similarities to Mycoplasma falconis and Mycoplasma gateae.

  6. 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...

  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. Mycoplasma genitalium: An emergent sexually transmitted disease?

    PubMed

    Manhart, Lisa E

    2013-12-01

    This article summarizes the epidemiologic evidence linking Mycoplasma genitalium to sexually transmitted disease syndromes, including male urethritis, and female cervicitis, pelvic inflammatory disease, infertility, and adverse birth outcomes. It discusses the relationship of this bacterium to human immunodeficiency virus infection and reviews the available literature on the efficacy of standard antimicrobial therapies against M genitalium.

  9. 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

  10. Cellular Microbiology of Mycoplasma canis

    PubMed Central

    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.

    2016-01-01

    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

  11. Chronic "Candidatus Mycoplasma turicensis" infection.

    PubMed

    Novacco, Marilisa; Boretti, Felicitas S; Wolf-Jäckel, Godelind A; Riond, Barbara; Meli, Marina L; Willi, Barbara; Lutz, Hans; Hofmann-Lehmann, Regina

    2011-04-20

    "Candidatus Mycoplasma turicensis" infects felids. The pathogenesis of "Candidatus M. turicensis" chronic infection is poorly understood. The goals of the present study were to (1) induce reactivation of the infection in chronic carrier cats by attempted immunosuppression, (2) identify potential tissue sequestration using real-time TaqMan® PCR and (3) monitor the humoral immune response by DnaK enzyme-linked immunosorbent assay (ELISA). Ten specified pathogen-free cats that had ostensibly recovered from experimental "Candidatus M. turicensis" infection were used: five cats (group 1) received high dose methylprednisolone (attempted immunosuppression), while five cats served as untreated controls (group 2). Besides weekly blood samples, tissue samples were collected from bone marrow, kidney, liver and salivary glands at selected time points. The cats in group 1 had significantly lower lymphocyte counts and higher blood glucose levels after methylprednisolone administration than the controls. After methylprednisolone administration one blood and three tissue samples from cats in group 1 tested PCR-positive; before the administration, only one sample was positive. All other samples tested PCR-negative. All cats stayed seropositive; the antibody levels of the cats in group 1 showed a significant transient decrease after methylprednisolone administration. This is the first study to report the presence of "Candidatus M. turicensis" in tissues of chronically infected cats and the persistence of anti-feline hemoplasma antibodies in the absence of detectable bacteremia. Methylprednisolone administration did not lead to a significant reactivation of the infection. Our results enhance the knowledge of "Candidatus M. turicensis" infection pathogenesis and are clinically relevant to the prognosis of hemoplasma-infected cats.

  12. Development of fluorescence expression tools to study host-mycoplasma interactions and validation in two distant mycoplasma clades.

    PubMed

    Bonnefois, Tiffany; Vernerey, Marie-Stéphanie; Rodrigues, Valérie; Totté, Philippe; Puech, Carinne; Ripoll, Chantal; Thiaucourt, François; Manso-Silván, Lucía

    2016-10-20

    Fluorescence expression tools for stable and innocuous whole mycoplasma cell labelling have been developed. A Tn4001-derivative mini-transposon affording unmarked, stable mutagenesis in mycoplasmas was modified to allow the constitutive, high-level expression of mCherry, mKO2 and mNeonGreen. These tools were used to introduce the respective fluorescent proteins as chromosomal tags in the phylogenetically distant species Mycoplasma mycoides subsp. mycoides and Mycoplasma bovis. The production, selection and characterisation of fluorescent clones were straightforward and resulted in the unprecedented observation of red and green fluorescent mycoplasma colonies in the two species, with no apparent cytotoxicity. Equivalent fluorescence expression levels were quantified by flow cytometry in both species, suggesting that these tools can be broadly applied in mycoplasmas. A macrophage infection assay was performed to assess the usefulness of mNeonGreen-expressing strains for monitoring mycoplasma infections, and notably cell invasion. The presence of fluorescent mycoplasmas inside live phagocytic cells was detected and quantified by flow cytometry and corroborated by confocal microscopy, which allowed the identification of individual mycoplasmas in the cytoplasm of infected cells. The fluorescence expression tools developed in this study are suitable for host-pathogen interaction studies and offer innumerable perspectives for the functional analysis of mycoplasmas both in vitro and in vivo.

  13. 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.

  14. Gliding hexapods and the origins of insect aerial behaviour

    PubMed Central

    Yanoviak, Stephen P; Kaspari, Michael; Dudley, Robert

    2009-01-01

    Directed aerial descent (i.e. gliding and manoeuvring) may be an important stage in the evolution of winged flight. Although hypothesized to occur in ancestrally wingless insects, such behaviour is unexplored in extant basal hexapods, but has recently been described in arboreal ants. Here we show that tropical arboreal bristletails (Archaeognatha) direct their horizontal trajectories to tree trunks in approximately 90 per cent of falls. Experimental manipulation of the median caudal filament significantly reduced both success rate (per cent of individuals landing on a tree trunk) and performance (glide index) versus controls. The existence of aerial control in the ancestrally wingless bristletails, and its habitat association with an arboreal lifestyle, are consistent with the hypothesis of a terrestrial origin for winged flight in insects. PMID:19324632

  15. Coupled glide-climb diffusion-enhanced crystal plasticity

    NASA Astrophysics Data System (ADS)

    Geers, M. G. D.; Cottura, M.; Appolaire, B.; Busso, E. P.; Forest, S.; Villani, A.

    2014-10-01

    This paper presents a fully coupled glide-climb crystal plasticity model, whereby climb is controlled by the diffusion of vacancies. An extended strain gradient crystal plasticity model is therefore proposed, which incorporates the climbing of dislocations in the governing transport equations. A global-local approach is adopted to separate the scales and assess the influence of local diffusion on the global plasticity problem. The kinematics of the crystal plasticity model is enriched by incorporating the climb kinematics in the crystallographic split of the plastic strain rate tensor. The potential of the fully coupled theory is illustrated by means of two single slip examples that illustrate the interaction between glide and climb in either bypassing a precipitate or destroying a dislocation pile-up.

  16. GLIDES – Efficient Energy Storage from ORNL

    ScienceCinema

    Momen, Ayyoub M.; Abu-Heiba, Ahmad; Odukomaiya, Wale; Akinina, Alla

    2016-07-12

    The research shown in this video features the GLIDES (Ground-Level Integrated Diverse Energy Storage) project, which has been under development at Oak Ridge National Laboratory (ORNL) since 2013. GLIDES can store energy via combined inputs of electricity and heat, and deliver dispatchable electricity. Supported by ORNL’s Laboratory Director’s Research and Development (LDRD) fund, this energy storage system is low-cost, and hybridizes compressed air and pumped-hydro approaches to allow for storage of intermittent renewable energy at high efficiency. A U.S. patent application for this novel energy storage concept has been submitted, and research findings suggest it has the potential to be a flexible, low-cost, scalable, high-efficiency option for energy storage, especially useful in residential and commercial buildings.

  17. Circular random motion in diatom gliding under isotropic conditions

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Medina, Braulio; Jiménez Guerra, Andrés; Peña Maldonado, Ana Iris; Covarrubias Rubio, Yadiralia; Viridiana García Meza, Jessica

    2014-12-01

    How cells migrate has been investigated primarily for the case of trajectories composed by joined straight segments. In contrast, little is known when cellular motion follows intrinsically curved paths. Here, we use time-lapse optical microscopy and automated trajectory tracking to investigate how individual cells of the diatom Nitzschia communis glide across surfaces under isotropic environmental conditions. We find a distinct kind of random motion, where trajectories are formed by circular arcs traveled at constant speed, alternated with random stoppages, direction reversals and changes in the orientation of the arcs. Analysis of experimental and computer-simulated trajectories show that the circular random motion of diatom gliding is not optimized for long-distance travel but rather for recurrent coverage of limited surface area. These results suggest that one main biological role for this type of diatom motility is to efficiently build the foundation of algal biofilms.

  18. 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.

  19. Gliding motility and Por secretion system genes are widespread among members of the phylum bacteroidetes.

    PubMed

    McBride, Mark J; 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.

  20. The biology of gliding in flying lizards (genus Draco) and their fossil and extant analogs.

    PubMed

    McGuire, Jimmy A; Dudley, Robert

    2011-12-01

    The flying lizards of the genus Draco are among the most remarkable and successful clades of gliding vertebrates. Here, we evaluate the evolution of gliding in Draco and other lizards, describe the suite of morphological innovations that characterize Draco, discuss the ecological context of gliding in this genus, describe functions of their patagial membranes that are not related to gliding, and summarize the interspecific allometry of the Draco gliding apparatus, as well as the corresponding consequences for their now empirically quantified gliding performance. Several fossil reptilian lineages had morphologies similar to that of modern Draco, with patagial membranes supported by elongated ribs or rib-like dermal structures. Using Draco's snout-vent length/mass relationships, we provide improved estimates of wing loading for three of these fossil gliders (Icarosaurus seifkeri, Kuehneosaurus sp., Coelurosauravus elivensis) and then estimate absolute gliding performance for each taxon by extrapolating from Draco's wing loading/glide performance relationship. We find that I. seifkeri likely represented the best nonflapping terrestrial vertebrate glider yet described, whereas the larger Kuehneosaurus and Coelurosauravus probably required high descent velocities to achieve sufficient lift for gliding, with commensurately greater height loss with each glide.

  1. Glide twinning and pseudotwinning in peristerite: twin morphology and propagation

    NASA Astrophysics Data System (ADS)

    Brown, William L.

    1989-07-01

    Optically visible Albite glide “twins” in a peristerite (˜An9Or1.6), identified from their tapering shape and relationship to grain boundaries, were studied by transmission electron microscopy. Near the tips in sections ⊥ a, the microstructure consists of small (˜400 nm long) lensshaped Albite twins centred exclusively on the oligoclase lamellae. The lenses extend partly outwards into the two adjacent low albite lamellae and induce strong inhomogeneous strain. Where the lenses are closer together, they form, depending on the sense of shear, nearly linear left or right-stepping en échelon arrays, with overlap of the strain fields. Slightly farther in from the tip, the twin domains coalesce to form continuous pinch-and-swell lamellae, being always thicker in the oligoclase. Because of Si,Al order, only elastic glide pseudotwins are possible in low albite. In oligoclase glide pseudotwins may be mechanically stable (metastable relative to Si,Al order) and may deviate only slightly from true twins. Pseudotwins develop first in the oligoclase, propagate dynamically by jumping across the intervening albite lamellae, extend lengthways and thicken sideways and finally coalesce. They are stabilized by diffusion-controlled inversion of Si,Al order giving rise to true twins described in a companion paper.

  2. 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)

  3. Development of the Gliding Hole of the Dynamics Compression Plate

    NASA Astrophysics Data System (ADS)

    Salim, U. A.; Suyitno; Magetsari, R.; Mahardika, M.

    2017-02-01

    The gliding hole of the dynamics compression plate is designed to facilitate relative movement of pedicle screw during surgery application. The gliding hole shape is then geometrically complex. The gliding hole manufactured using machining processes used to employ ball-nose cutting tool. Then, production cost is expensive due to long production time. This study proposed to increase productivity of DCP products by introducing forming process (cold forming). The forming process used to involve any press tool devices. In the closed die forming press tool is designed with little allowance, then work-pieces is trapped in the mould after forming. Therefore, it is very important to determine hole geometry and dimensions of raw material in order to success on forming process. This study optimized the hole sizes with both geometry analytics and experiments. The success of the forming process was performed by increasing the holes size on the raw materials. The holes size need to be prepared is diameter of 5.5 mm with a length of 11.4 mm for the plate thickness 3 mm and diameter of 6 mm with a length of 12.5 mm for the plate thickness 4 mm.

  4. Secretomes of Mycoplasma hyopneumoniae and Mycoplasma flocculare reveal differences associated to pathogenesis.

    PubMed

    Paes, Jéssica A; Lorenzatto, Karina R; de Moraes, Sofia N; Moura, Hercules; Barr, John R; Ferreira, Henrique B

    2017-02-10

    Mycoplasma hyopneumoniae and Mycoplasma flocculare cohabit the porcine respiratory tract. However, M. hyopneumoniae causes the porcine enzootic pneumonia, while M. flocculare is a commensal bacterium. Comparative analyses demonstrated high similarity between these species, which includes the sharing of all predicted virulence factors. Nevertheless, studies related to soluble secretomes of mycoplasmas were little known, although they are important for bacterial-host interactions. The aim of this study was to perform a comparative analysis between the soluble secreted proteins repertoires of the pathogenic Mycoplasma hyopneumoniae and its closely related commensal Mycoplasma flocculare. For that, bacteria were cultured in medium with reduced serum concentration and secreted proteins were identified by a LC-MS/MS proteomics approach. Altogether, 62 and 26 proteins were identified as secreted by M. hyopneumoniae and M. flocculare, respectively, being just seven proteins shared between these bacteria. In M. hyopneumoniae secretome, 15 proteins described as virulence factors were found; while four putative virulence factors were identified in M. flocculare secretome. For the first time, clear differences related to virulence were found between these species, helping to elucidate the pathogenic nature of M. hyopneumoniae to swine hosts.

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

    PubMed

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

    2013-03-05

    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 tRNA(Leu), 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.

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

    PubMed

    Hu, Xiaopeng; Yu, Jie; Zhou, Xiang; Li, Zhaoming; Xia, Yun; Luo, Zhiyong; Wu, Yaqun

    2014-03-01

    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.

  7. 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.

  8. 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.

  9. Mycoplasma gallisepticum invades chicken erythrocytes during infection.

    PubMed

    Vogl, Gunther; Plaickner, Astrid; Szathmary, Susan; Stipkovits, László; Rosengarten, Renate; Szostak, Michael P

    2008-01-01

    Recently, it was demonstrated using in vitro assays that the avian pathogen Mycoplasma gallisepticum is able to invade nonphagocytic cells. It was also shown that this mycoplasma can survive and multiply intracellularly for at least 48 h and that this cell invasion capacity contributes to the systemic spread of M. gallisepticum from the respiratory tract to the inner organs. Using the gentamicin invasion assay and a differential immunofluorescence technique combined with confocal laser scanning microscopy, we were able to demonstrate in in vitro experiments that M. gallisepticum is also capable of invading sheep and chicken erythrocytes. The frequencies of invasion of three well-defined M. gallisepticum strains were examined over a period of 24 h, and a significant increase in invasiveness occurred after 8 h of infection. In addition, blood samples derived from chickens experimentally infected via the aerosol route with the virulent strain M. gallisepticum R(low) were analyzed. Surprisingly, M. gallisepticum R(low) was detected in the bloodstream of infected chickens by nested PCR, as well as by differential immunofluorescence and interference contrast microscopy that showed that mycoplasmas were not only on the surface but also inside chicken erythrocytes. This finding provides novel insight into the pathomechanism of M. gallisepticum and may have implications for the development of preventive strategies.

  10. Competitor internal standards for quantitative detection of mycoplasma DNA.

    PubMed

    Sidhu, M K; Rashidbaigi, A; Testa, D; Liao, M J

    1995-05-01

    Homologous internal controls were used as competitor DNA in the polymerase chain reaction for the quantitative detection of mycoplasma DNA. PCR primer sets were designed on the basis of the most conserved nucleotide sequences of the 16S rRNA gene of mycoplasma species. Amplification of this gene was examined in five different mycoplasma species: Mycoplasma orale, M. hyorhinus, M. synoviae, M. gallisepticum and M. pneumoniae. To evaluate the primers, a number of different cell lines were assayed for the detection of mycoplasma infections. All positive cell lines showed a distinct product on agarose gels while uninfected cells showed no DNA amplification. Neither bacterial nor eukaryotic DNA produced any cross-reaction with the primers used, thus confirming their specificity. Internal control DNA to be used for quantitation was constructed by modifying the sizes of the wild-type amplified products and cloning them in plasmid vectors. These controls used the same primer binding sites as the wild-type and the amplified products were differentiated by a size difference. The detection limits for all the mycoplasma species by competitive quantitative PCR were estimated to range from 4 to 60 genome copies per assay as determined by ethidium bromide-stained agarose gels. These internal standards also serve as positive controls in PCR-based detection of mycoplasma DNA, and therefore accidental contamination of test samples with wild-type positive controls can be eliminated. The quantitative PCR method developed will be useful in monitoring the progression and significance of mycoplasma in the disease process.

  11. "Candidatus Mycoplasma haemomacaque" and Bartonella quintana bacteremia in cynomolgus monkeys.

    PubMed

    Maggi, Ricardo G; Mascarelli, Patricia E; Balakrishnan, Nandhakumar; Rohde, Cynthia M; Kelly, Catherine M; Ramaiah, Lila; Leach, Michael W; Breitschwerdt, Edward B

    2013-05-01

    Here, we report latent infections with Bartonella quintana and a hemotropic Mycoplasma sp. in a research colony of cynomolgus monkeys (Macaca fascicularis). Sequence alignments, evolutionary analysis, and signature nucleotide sequence motifs of the hemotropic Mycoplasma 16S rRNA and RNase P genes indicate the presence of a novel organism.

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

    PubMed

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

    2015-09-01

    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.

  13. 21 CFR 610.30 - Test for Mycoplasma.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... produced from in vitro living cell cultures, and prior to inactivation in the case of inactivated virus vaccines produced from such living cell cultures, each virus harvest pool and control fluid pool shall be... Mycoplasma and each test shall include control cultures of at least two known strains of Mycoplasma, one...

  14. Cyclic fatigue of instruments for endodontic glide path.

    PubMed

    Gambarini, Gianluca; Plotino, Gianluca; Sannino, GianPaolo; Grande, Nicola Maria; Giansiracusa, Alessio; Piasecki, Lucila; da Silva Neto, Ulisses Xavier; Al-Sudani, Dina; Testarelli, Luca

    2015-01-01

    Endodontic glide path is the creation of a smooth patency from canal orifice to apex, which can be performed manually or with small tapered NiTi rotary instruments. The use of stainless steel (SS) hand K-files inserted in a reciprocating handpiece can be a possible alternative to create a mechanical glide path. The aim of this study was to compare the cyclic fatigue resistance between SS K-files used in a reciprocating motion and NiTi rotary instruments in artificial curved canals. Ten SS size 15 K-files used with the M4 handpiece (SybronEndo, Glendora, CA, USA) and ten PathFiles (Maillefer-Dentsply, Ballaigues, CH, Switzerland) NiTi rotary instruments size 16, 0.02 taper were tested for resistance to cyclic fatigue. The time to fracture inside an artificial curved canal was recorded for each instrument. Data were analyzed by one-way ANOVA and Tukey HSD test. Mean time (and SD) to failure was 464 s (±40.4) for the Group PF (NiTi rotary PathFile), and 1049 s (±24.8) for the Group M4 (SS K-files reciprocating) with a statistically significant difference between the two groups (p = 0.033). The SS 15 K-files used with the M4 handpiece showed a significant greater resistance to cyclic fatigue when compared to the NiTi rotary PathFiles. Therefore, the use of small size SS files in a reciprocating motion might be a rational choice for the creation of a mechanical endodontic glide path in curved root canals.

  15. Repetition Pitch glide from the step pyramid at Chichen Itza.

    PubMed

    Bilsen, Frans A

    2006-08-01

    Standing at the foot of the Mayan step pyramid at Chichen Itza in Mexico, one can produce a pitchy "chirp" echo by handclapping. As exposed by Declercq et al. [J. Acoust. Soc. Am. 116, 3328-3335 (2004)], an acoustic model based on optical Bragg diffraction at a periodic structure cannot explain satisfactorily the chirp-echo sonogram. Alternatively, considering the echo as a sequence of reflections, and given the dimensions of the pyramid and source-receiver position, the chirp is predicted correctly as a Repetition Pitch glide of which the pitch height is continuously decreasing within 177 ms from 796 to 471 Hz-equivalent.

  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. Animal flight dynamics I. Stability in gliding flight.

    PubMed

    Thomas, A L; Taylor, G K

    2001-10-07

    Stability is as essential to flying as lift itself, but previous discussions of how flying animals maintain stability have been limited in both number and scope. By developing the pitching moment equations for gliding animals and by discussing potential sources of roll and yaw stability, we consider the various sources of static stability used by gliding animals. We find that gliding animals differ markedly from aircraft in how they maintain stability. In particular, the pendulum stability provided when the centre of gravity lies below the wings is a much more important source of stability in flying animals than in most conventional aircraft. Drag-based stability also appears to be important for many gliding animals, whereas in aircraft, drag is usually kept to a minimum. One unexpected consequence of these differences is that the golden measure of static pitching stability in aircraft--the static margin--can only strictly be applied to flying animals if the equilibrium angle of attack is specified. We also derive several rules of thumb by which stable fliers can be identified. Stable fliers are expected to exhibit one or more of the following features: (1) Wings that are swept forward in slow flight. (2) Wings that are twisted down at the tips when swept back (wash-out) and twisted up at the tips when swept forwards (wash-in). (3) Additional lifting surfaces (canard, hindwings or a tail) inclined nose-up to the main wing if they lie forward of it, and nose-down if they lie behind it (longitudinal dihedral). Each of these predictions is directional--the opposite is expected to apply in unstable animals. In addition, animals with reduced stability are expected to display direct flight patterns in turbulent conditions, in contrast to the erratic flight patterns predicted for stable animals, in which large restoring forces are generated. Using these predictions, we find that flying animals possess a far higher degree of inherent stability than has generally been

  19. Alice in Wonderland syndrome associated with mycoplasma infection.

    PubMed

    Omata, Taku; Fujii, Katsunori; Kuroki, Haruo; Shimojo, Naoki

    2016-10-01

    Alice in Wonderland syndrome (AIWS) is a rare condition in which patients report distorted size perception of objects and their own bodies. Although specific causes and pathology have not been elucidated, an association between AIWS and infection has been suggested. To our knowledge, mycoplasma-induced AIWS has not been examined. A girl aged 7 years 11 months presented with fever (temperature, 40°C) and cough. Although the fever disappeared after approximately 10 days, she complained that her mother's face suddenly appeared smaller to her. Subsequently, she complained that objects intermittently appeared smaller than normal. Particle agglutination test indicated elevated serum antibodies against Mycoplasma pneumoniae. The patient was therefore diagnosed the patient with AIWS secondary to mycoplasma infection. Although mycoplasma infection is known to cause various central nervous system symptoms, this is the first report involving AIWS, suggesting that mycoplasma could affect visual function in children.

  20. Putative essential and core-essential genes in Mycoplasma genomes.

    PubMed

    Lin, Yan; Zhang, Randy Ren

    2011-01-01

    Mycoplasma, which was used to create the first "synthetic life", has been an important species in the emerging field, synthetic biology. However, essential genes, an important concept of synthetic biology, for both M. mycoides and M. capricolum, as well as 14 other Mycoplasma with available genomes, are still unknown. We have developed a gene essentiality prediction algorithm that incorporates information of biased gene strand distribution, homologous search and codon adaptation index. The algorithm, which achieved an accuracy of 80.8% and 78.9% in self-consistence and cross-validation tests, respectively, predicted 5880 essential genes in the 16 Mycoplasma genomes. The intersection set of essential genes in available Mycoplasma genomes consists of 153 core essential genes. The predicted essential genes (available from pDEG, tubic.tju.edu.cn/pdeg) and the proposed algorithm can be helpful for studying minimal Mycoplasma genomes as well as essential genes in other genomes.

  1. Putative essential and core-essential genes in Mycoplasma genomes

    PubMed Central

    Lin, Yan; Zhang, Randy Ren

    2011-01-01

    Mycoplasma, which was used to create the first “synthetic life”, has been an important species in the emerging field, synthetic biology. However, essential genes, an important concept of synthetic biology, for both M. mycoides and M. capricolum, as well as 14 other Mycoplasma with available genomes, are still unknown. We have developed a gene essentiality prediction algorithm that incorporates information of biased gene strand distribution, homologous search and codon adaptation index. The algorithm, which achieved an accuracy of 80.8% and 78.9% in self-consistence and cross-validation tests, respectively, predicted 5880 essential genes in the 16 Mycoplasma genomes. The intersection set of essential genes in available Mycoplasma genomes consists of 153 core essential genes. The predicted essential genes (available from pDEG, tubic.tju.edu.cn/pdeg) and the proposed algorithm can be helpful for studying minimal Mycoplasma genomes as well as essential genes in other genomes. PMID:22355572

  2. Significance of Genital Mycoplasmas in Pelvic Inflammatory Disease: Innocent Bystander!

    PubMed Central

    Harmanli, Ozgur H.; Nyirjesy, Paul; Reece, E. Albert

    1996-01-01

    Objective: Our objective was to determine the role of Mycoplasma hominis and Ureaplasma urealyticum in pelvic inflammatory disease (PID). Methods: The clinical and microbiologic variables in 114 patients with a clinical diagnosis of PID were compared prospectively according to the isolation of M. hominis and U. urealyticum from their endometrial cavities. Results: The groups were epidemiologically well matched. Clinical parameters such as temperature, leukocyte count, erythrocyte count, and C-reactive protein on admission and length of hospital stay were similar in the patients, regardless of their mycoplasma status. A significant percentage of the patients either continued or started to harbor genital mycoplasmas after the resolution of PID without any significant clinical sequelae. Conclusions: The presence of genital mycoplasmas does not change the clinical presentation and course of PID. Both M. hominis and U. urealyticum can persist or colonize the endometrium after complete recovery from PID. Therefore, the genital mycoplasmas do not seem to have a dominant pathogenic role in PID. PMID:18476105

  3. Gliding Motility of Babesia bovis Merozoites Visualized by Time-Lapse Video Microscopy

    PubMed Central

    Asada, Masahito; Goto, Yasuyuki; Yahata, Kazuhide; Yokoyama, Naoaki; Kawai, Satoru; Inoue, Noboru; Kaneko, Osamu; Kawazu, Shin-ichiro

    2012-01-01

    Background Babesia bovis is an apicomplexan intraerythrocytic protozoan parasite that induces babesiosis in cattle after transmission by ticks. During specific stages of the apicomplexan parasite lifecycle, such as the sporozoites of Plasmodium falciparum and tachyzoites of Toxoplasma gondii, host cells are targeted for invasion using a unique, active process termed “gliding motility”. However, it is not thoroughly understood how the merozoites of B. bovis target and invade host red blood cells (RBCs), and gliding motility has so far not been observed in the parasite. Methodology/Principal Findings Gliding motility of B. bovis merozoites was revealed by time-lapse video microscopy. The recorded images revealed that the process included egress of the merozoites from the infected RBC, gliding motility, and subsequent invasion into new RBCs. The gliding motility of B. bovis merozoites was similar to the helical gliding of Toxoplasma tachyzoites. The trails left by the merozoites were detected by indirect immunofluorescence assay using antiserum against B. bovis merozoite surface antigen 1. Inhibition of gliding motility by actin filament polymerization or depolymerization indicated that the gliding motility was driven by actomyosin dependent process. In addition, we revealed the timing of breakdown of the parasitophorous vacuole. Time-lapse image analysis of membrane-stained bovine RBCs showed formation and breakdown of the parasitophorous vacuole within ten minutes of invasion. Conclusions/Significance This is the first report of the gliding motility of B. bovis. Since merozoites of Plasmodium parasites do not glide on a substrate, the gliding motility of B. bovis merozoites is a notable finding. PMID:22506073

  4. 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

  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. The Selection of Glide Slope Antenna Patterns for Use in the Frequency Assignment Process

    DTIC Science & Technology

    1979-07-01

    3 CONIUcSIONS ---------------------------------------------------------- 5 RECOMMENDED ANTENNA...is therefore still required. Additional data would also be helpful on the A.I.L. Type 55 glide slope and the end-fire slotted cable system. 5 ...Inc.. June 30, 1970. 5 . FAA Preliminary Instruction Book TI 6750.44, "Glide Slope Antenna System, Part of Mark I Instrument Landirl System," FAA

  7. Amoeboid cells use protrusions for walking, gliding and swimming.

    PubMed

    Van Haastert, Peter J M

    2011-01-01

    Amoeboid cells crawl using pseudopods, which are convex extensions of the cell surface. In many laboratory experiments, cells move on a smooth substrate, but in the wild cells may experience obstacles of other cells or dead material, or may even move in liquid. To understand how cells cope with heterogeneous environments we have investigated the pseudopod life cycle of wild type and mutant cells moving on a substrate and when suspended in liquid. We show that the same pseudopod cycle can provide three types of movement that we address as walking, gliding and swimming. In walking, the extending pseudopod will adhere firmly to the substrate, which allows cells to generate forces to bypass obstacles. Mutant cells with compromised adhesion can move much faster than wild type cells on a smooth substrate (gliding), but cannot move effectively against obstacles that provide resistance. In a liquid, when swimming, the extending pseudopods convert to side-bumps that move rapidly to the rear of the cells. Calculations suggest that these bumps provide sufficient drag force to mediate the observed forward swimming of the cell.

  8. The epidemiology of injury in hang-gliding and paragliding.

    PubMed

    Rekand, Tiina

    2012-01-01

    Para- and hang-gliding are modern air sports that developed in the 20th century. Performers should possess technical skills and manage certified equipment for successful flight. Injuries may happen during the take-off, flight and landing. PubMed was searched using the search terms 'paragliding' and/or 'hang-gliding'. The reference lists of articles identified in the search strategy were also searched for relevant articles. The most common injuries are fractures, dislocations or sprains in the extremities, followed by spinal and head traumas. Multiple injuries after accidents are common. Collision with electrical wires may cause burn injuries. Fatal outcomes are caused by brain injuries, spinal cord injuries at the cervical level or aorta rupture. Accidents happen because of risk-taking behavior, lack of education or use of self-modified equipment. Observational studies have suggested the need for protection of the head, trunk and lower extremities. The measures proposed are often based on conclusions of observational studies and not proven through randomized studies. Better education along with focusing on possible risk factors will probably diminish the risks of hang- and paragliding. Large denominator-based case series, case-control and population-based studies are needed for assessment of the risks of hang- and paragliding.

  9. 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.

  10. Plastic deformation of tubular crystals by dislocation glide

    NASA Astrophysics Data System (ADS)

    Beller, Daniel A.; Nelson, David R.

    2016-09-01

    Tubular crystals, two-dimensional lattices wrapped into cylindrical topologies, arise in many contexts, including botany and biofilaments, and in physical systems such as carbon nanotubes. The geometrical principles of botanical phyllotaxis, describing the spiral packings on cylinders commonly found in nature, have found application in all these systems. Several recent studies have examined defects in tubular crystals associated with crystalline packings that must accommodate a fixed tube radius. Here we study the mechanics of tubular crystals with variable tube radius, with dislocations interposed between regions of different phyllotactic packings. Unbinding and separation of dislocation pairs with equal and opposite Burgers vectors allow the growth of one phyllotactic domain at the expense of another. In particular, glide separation of dislocations offers a low-energy mode for plastic deformations of solid tubes in response to external stresses, reconfiguring the lattice step by step. Through theory and simulation, we examine how the tube's radius and helicity affects, and is in turn altered by, the mechanics of dislocation glide. We also discuss how a sufficiently strong bending rigidity can alter or arrest the deformations of tubes with small radii.

  11. New models of chronic synovitis in rabbits induced by mycoplasmas: microbiological, histopathological, and immunological observations on rabbits injected with Mycoplasma arthritidis and Mycoplasma pulmonis.

    PubMed Central

    Cole, B C; Griffiths, M M; Eichwald, E J; Ward, J R

    1977-01-01

    A dose-dependent chronic synovitis was induced in rabbit knees after the intra-articular injection of both Mycoplasma arthritidis and Mycoplasma pulmonis. The inflammation progressed from an initial acute phase at 1 week characterized by edema, infiltration of the synovium with monocytes and heterophils, and desquamation of lining cells, to a more chronic phase at 1 and 3 months, in which villus hyperplasia, lymph "nodules," mononuclear cell infiltration, fibroplasia, and collagen deposition were prominent. With one exception, mycoplasmas could no longer be cultivated from the joints 1 month postinoculation. Both mycoplasma species evoked a humoral antibody response that was more marked in synovial fluids than in peripheral blood. A cell-mediated immune reaction, as evidence by enhanced uptake by [3H]thymidine by sensitized blood, spleen, or node lymphocytes in the presence of homologous antigen, was detected only in rabbits injected with M. pulmonis. Lymphocytes taken from arthritic rabbits were no more cytotoxic toward synovial cells derived from normal or arthritic rabbits than were normal lymphocytes. The models of synovitis described in this study offer a convenient probe for determining the mechanisms of mycoplasma-induced inflammation, since they require only a single injection of the initiating agent and, in addition, utilize an animal host large enough for detailed investigation into the nature of mycoplasma/synovium interactions. Images PMID:873616

  12. 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.

  13. Quantitative assessment of Mycoplasma hemadsorption activity by flow cytometry.

    PubMed

    García-Morales, Luis; González-González, Luis; Costa, Manuela; Querol, Enrique; Piñol, Jaume

    2014-01-01

    A number of adherent mycoplasmas have developed highly complex polar structures that are involved in diverse aspects of the biology of these microorganisms and play a key role as virulence factors by promoting adhesion to host cells in the first stages of infection. Attachment activity of mycoplasma cells has been traditionally investigated by determining their hemadsorption ability to red blood cells and it is a distinctive trait widely examined when characterizing the different mycoplasma species. Despite the fact that protocols to qualitatively determine the hemadsorption or hemagglutination of mycoplasmas are straightforward, current methods when investigating hemadsorption at the quantitative level are expensive and poorly reproducible. By using flow cytometry, we have developed a procedure to quantify rapidly and accurately the hemadsorption activity of mycoplasmas in the presence of SYBR Green I, a vital fluorochrome that stains nucleic acids, allowing to resolve erythrocyte and mycoplasma cells by their different size and fluorescence. This method is very reproducible and permits the kinetic analysis of the obtained data and a precise hemadsorption quantification based on standard binding parameters such as the dissociation constant K d. The procedure we developed could be easily implemented in a standardized assay to test the hemadsorption activity of the growing number of clinical isolates and mutant strains of different mycoplasma species, providing valuable data about the virulence of these microorganisms.

  14. 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.

  15. 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.

  16. Ocular manifestations of Mycoplasma pneumoniae infection.

    PubMed

    Salzman, M B; Sood, S K; Slavin, M L; Rubin, L G

    1992-05-01

    Ocular manifestations of Mycoplasma pneumoniae infection, other than conjunctivitis, are uncommon. Optic disk swelling, optic nerve atrophy, retinal exudates and hemorrhages, and cranial nerve palsies have been infrequently reported. We describe a 15-year-old patient who developed bilateral optic disk edema and iritis during an acute infection with M. pneumoniae and review the world literature on findings associated with ocular manifestations of infection with this pathogen. Although our patient experienced complete resolution of iritis and optic disk edema after 6 weeks, several patients described in the literature have experienced permanent sequelae as a result of optic neuropathy.

  17. Neurological complications of Mycoplasma pneumoniae infection.

    PubMed

    Hely, M A; Williamson, P M; Terenty, T R

    1984-01-01

    This study documents five patients with neurological disease associated with evidence of recent Mycoplasma pneumoniae infection. Four patients had encephalitis associated with coma. Two of these had hemiparesis (one with dysphasia), one had seizures, and one had cerebellar and brainstem involvement. Two also had evidence of a radiculopathy and peripheral neuropathy. One patient had aseptic meningitis with later transverse myelitis. Three patients had multiple sites of neurological involvement. Respiratory infections preceded the neurological syndromes in four cases. Antibiotic therapy did not appear to alter the course of the disease. All patients had a favourable outcome.

  18. Cloning of the complete Mycoplasma pneumoniae genome.

    PubMed Central

    Wenzel, R; Herrmann, R

    1989-01-01

    The complete genome of Mycoplasma pneumoniae was cloned in an ordered library consisting of 34 overlapping or adjacent cosmids, one plasmid and two lambda phages. The genome size was determined by adding up the sizes of either the individual unique EcoRI restriction fragments of the gene bank or of the XhoI fragments of genomic M. pneumoniae DNA. The values from these calculations, 835 and 849 kbp, are in good agreement. An XhoI restriction map was constructed by identifying adjacent DNA fragments by probing with selected cosmid clones. Images PMID:2506532

  19. Effect of a Mycoplasma hominis-like Mycoplasma on the infection of HEp-2 cells by the TW-183 strain of Chlamydia pneumoniae.

    PubMed

    Castilla, E A; Wadowsky, R M

    2000-02-01

    We isolated a Mycoplasma hominis-like mycoplasma from a stock culture of Chlamydia pneumoniae TW-183 obtained from the American Type Culture Collection and eradicated the contaminant by treating the stock suspension with a nonionic detergent, Igepal CA-630. The M. hominis-like mycoplasma neither inhibits nor enhances the infectivity of C. pneumoniae for HEp-2 cells.

  20. Sequence homologies between Mycoplasma and Chlamydia spp. lead to false-positive results in chlamydial cell cultures tested for mycoplasma contamination with a commercial PCR assay.

    PubMed

    Maass, Viola; Kern, Jan Marco; Poeckl, Matthias; Maass, Matthias

    2011-10-01

    Mycoplasma contamination is a frequent problem in chlamydial cell culture. After obtaining contradictory contamination results, we compared three commercial PCR kits for mycoplasma detection. One kit signaled contamination in mycoplasma-free Chlamydia pneumoniae cultures. Sequencing of cloned PCR products revealed primer homology with the chlamydial genome as the basis of this false-positive result.

  1. Catalase Enhances Growth and Biofilm Production of Mycoplasma pneumoniae

    PubMed Central

    Simmons, Warren L.; Dybvig, Kevin

    2015-01-01

    Mycoplasma pneumoniae causes chronic respiratory disease in humans. Factors thought to be important for colonization include the ability of the mycoplasma to form a biofilm on epithelial surfaces and the production of hydrogen peroxide to damage host tissue. Almost all of the mycoplasmas, including M. pneumoniae, lack superoxide dismutase and catalase and a balance should exist between peroxide production and growth. We show here that the addition of catalase to cultures enhanced the formation of biofilms and altered the structure. The incorporation of catalase in agar increased the number of colony-forming units detected and hence could improve the clinical diagnosis of mycoplasmal diseases. PMID:25894997

  2. 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.

  3. 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.

  4. Mycoplasma hominis necrotizing pleuropneumonia in a previously healthy adolescent

    PubMed Central

    2010-01-01

    Background Mycoplasma hominis is a fastidious micro-organism causing systemic infections in the neonate and genital infections in the adult. It can also be the cause of serious extra-genital infections, mainly in immunosuppressed or predisposed subjects. Case Presentation We describe a case of severe pneumonia and pericarditis due to Mycoplasma hominis in a previously healthy adolescent who did not respond to initial therapy. Conclusions Mycoplasma hominis could be an underestimated cause of severe pneumonia in immunocompetent patients and should be particularly suspected in those not responding to standard therapy. PMID:21106079

  5. 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.

  6. 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.

  7. 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.

  8. Effects of Surface Passivation on Gliding Motility Assays

    DTIC Science & Technology

    2011-06-03

    mM EGTA (Sigma 80635), 10 mM MgCl2 (Sigma M1028) and pH -ed to 6.89 using approximately 1.25 M NaOH (Fisher S318) in 18.2 MV-cm water. The amount of...NaOH was approximate since each solution of PEM was pH -ed to 6.89. Böhm [11] showed that gliding speed was affected by both the pH and the ionic...strength of the solution the motors were in. In an effort to reduce as many variables as possible for speed measurements, we chose to maintain the pH of

  9. Gliding Motility Revisited: How Do the Myxobacteria Move without Flagella?

    PubMed Central

    Mauriello, Emilia M. F.; Mignot, Tâm; Yang, Zhaomin; Zusman, David R.

    2010-01-01

    Summary: In bacteria, motility is important for a wide variety of biological functions such as virulence, fruiting body formation, and biofilm formation. While most bacteria move by using specialized appendages, usually external or periplasmic flagella, some bacteria use other mechanisms for their movements that are less well characterized. These mechanisms do not always exhibit obvious motility structures. Myxococcus xanthus is a motile bacterium that does not produce flagella but glides slowly over solid surfaces. How M. xanthus moves has remained a puzzle that has challenged microbiologists for over 50 years. Fortunately, recent advances in the analysis of motility mutants, bioinformatics, and protein localization have revealed likely mechanisms for the two M. xanthus motility systems. These results are summarized in this review. PMID:20508248

  10. Numerical Investigation of Swimmer's Gliding Stage with 6-DOF Movement.

    PubMed

    Li, Tianzeng; Cai, Wenhao; Zhan, Jiemin

    2017-01-01

    The purpose of this study is to analyze the motion status of swimmers during their gliding stage using a numerical simulation method. This simulation strategy is conducted by solving the 3D incompressible Navier-Stokes equations using the Realizable k-ε turbulence closure equations in combination with the Six Degrees of Freedom (6-DOF) method. The uneven mass distribution of a swimmer and the roughness of the surface of the body are taken into consideration. The hydrodynamic characteristics and movement characteristics of the swimmers at different launch speeds were analyzed. The calculated results suggest that an optimal instant for starting propulsive movement is when the velocity of the swimmer decreases by 1.75 m/s to 2.0 m/s from an initial horizontal velocity of 3.1 m/s to 3.5 m/s.

  11. 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.

  12. Asset and prime - Gliding re-entry test vehicles

    NASA Astrophysics Data System (ADS)

    Powell, J. W.; Hengeveld, E.

    1983-08-01

    The history of the USAF development programs for winged controlled-reentry vehicles based on a dynamic-gliding principle, ASSET (1957-1965) and PRIME (1964-1967), is recounted. The ASSET program, developed from the initial Dyna-Soar project, comprised three aerothermodynamic-structural vehicles and three aerothermoelastic vehicles, all utilizing exotic refractory metal structures partially coated with silicon-boron, zirconia-ceramic nose caps, and LV-2C Thor launchers. The three PRIME SV-5D vehicles employed elastomeric-blanket ablative heat shields and molded carbon-phenolic-composite nose caps and were launched by SLV-3 Atlas rockets. It is noted that these projects, although successful, did not lead directly to the production of lifting-body or winged reentry vehicles, but rather provided data useful in the later Shuttle development program.

  13. 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.

  14. Leaping shampoo glides on a lubricating air layer.

    PubMed

    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.

  15. Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation

    PubMed Central

    Cattani, Amanda Malvessi; Siqueira, Franciele Maboni; Guedes, Rafael Lucas Muniz; Schrank, Irene Silveira

    2016-01-01

    Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5’ upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile. PMID:28005945

  16. Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation.

    PubMed

    Cattani, Amanda Malvessi; Siqueira, Franciele Maboni; Guedes, Rafael Lucas Muniz; Schrank, Irene Silveira

    2016-01-01

    Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5' upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile.

  17. Mycoplasma genitalium: An emerging sexually transmitted pathogen

    PubMed Central

    Sethi, Sunil; Singh, Gagandeep; Samanta, Palash; Sharma, Meera

    2012-01-01

    Mycoplasma genitalium is a member of genital mycoplasmas, which is emerging as an important causative agent of sexually transmitted infections both in males and females. The advent of polymerase chain reaction and other molecular methods have made studies on M. genitalium more feasible, which is otherwise a difficult organism to isolate. Besides Chlamydia trachomatis, M. genitalium is now an important and established cause of non gonococcal urethritis (NGU) in men, more so in persistent and recurrent NGU. Multiple studies have also shown a positive association of M. genitalium with mucopurulent cervicitis and vaginal discharge in females as well. The evidences for M. genitalium pelvic inflammatory diseases and infertility are quite convincing and indicate that this organism has potential to cause ascending infection. Lack of clear association with M. genitalium has been reported for bacterial vaginosis and adverse pregnancy outcomes. Diagnosis of M. genitalium infections is performed exclusively using nucleic acid amplification tests (NAATs), owing to poor or slow growth of bacterium in culture. Although there are no guidelines available regarding treatment, macrolide group of antimicrobials appear to be more effective than tetracyclines. The present review provides an overview of the epidemiology, pathogenesis, clinical presentation and management of sexually transmitted infections due to M. genitalium. PMID:23391789

  18. 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.

  19. Mycoplasma hominis Induces Mediastinitis after a Tonsillar Abscess

    PubMed Central

    Grancini, Anna; Colosimo, Manuela; Restelli, Antonella; Colombo, Rosaria; Maraschini, Anna; Pozzi, Cristina; Breda, Giuseppe; Protti, Alessandro; Arghittu, Milena; Maiavacca, Rita

    2016-01-01

    Mycoplasma hominis is commonly involved in genitourinary tract infections. We report a 59-year-old man who developed a M. hominis-associated mediastinitis following acute tonsillar infection. PMID:27957362

  20. Characteristics of a new sterol-nonrequiring Mycoplasma.

    PubMed

    Tully, J G; Razin, S

    1969-06-01

    Two Mycoplasma strains recovered from tissue culture environments were found to grow in complex media devoid of serum or serum fractions containing cholesterol and in a cholesterol-free synthetic medium. Neither strain was capable of synthesizing pigmented carotenoids, although these compounds are present in, and characteristic of, other sterol-nonrequiring mycoplasmas. Serological tests and an analysis of their cell protein patterns obtained by gel electrophoresis indicated that the isolates were similar to each other but distinct from other sterol-nonrequiring serotypes, Mycoplasma laidlawii and M. granularum, as well as from sterol-requiring species. The existence of Mycoplasma other than M. laidlawii and M. granularum without sterol requirements suggested the need for some taxonomic changes in this group of organisms.

  1. Onboard Determination of Vehicle Glide Capability for Shuttle Abort Flight Managment (SAFM)

    NASA Technical Reports Server (NTRS)

    Straube, Timothy; Jackson, Mark; Fill, Thomas; Nemeth, Scott

    2002-01-01

    When one or more main engines fail during ascent, the flight crew of the Space Shuttle must make several critical decisions and accurately perform a series of abort procedures. One of the most important decisions for many aborts is the selection ofa landing site. Several factors influence the ability to reach a landing site, including the spacecraft point of atmospheric entry, the energy state at atmospheric entry, the vehicle glide capability from that energy state, and whether one or more suitable landing sites are within the glide capability. Energy assessment is further complicated by the fact that phugoid oscillations in total energy influence glide capability. Once the glide capability is known, the crew must select the "best" site option based upon glide capability and landing site conditions and facilities. Since most of these factors cannot currently be assessed by the crew in flight, extensive planning is required prior to each mission to script a variety of procedures based upon spacecraft velocity at the point of engine failure (or failures). The results of this preflight planning are expressed in tables and diagrams on mission-specific cockpit checklists. Crew checklist procedures involve leafing through several pages of instructions and navigating a decision tree for site selection and flight procedures - all during a time critical abort situation. With the advent of the Cockpit Avionics Upgrade (CAU), the Shuttle will have increased on-board computational power to help alleviate crew workload during aborts and provide valuable situational awareness during nominal operations. One application baselined for the CAU computers is Shuttle Abort Flight Management (SAFM), whose requirements have been designed and prototyped. The SAFM application includes powered and glided flight algorithms. This paper describes the glided flight algorithm which is dispatched by SAFM to determine the vehicle glide capability and make recommendations to the crew for site

  2. 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

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

    PubMed

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

    1993-02-01

    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.

  4. Functional characterization of the RuvB homologs from Mycoplasma pneumoniae and Mycoplasma genitalium.

    PubMed

    Estevão, Silvia; Sluijter, Marcel; Hartwig, Nico G; van Rossum, Annemarie M C; Vink, Cornelis

    2011-12-01

    Homologous recombination between repeated DNA elements in the genomes of Mycoplasma species has been hypothesized to be a crucial causal factor in sequence variation of antigenic proteins at the bacterial surface. To investigate this notion, studies were initiated to identify and characterize the proteins that form part of the homologous DNA recombination machinery in Mycoplasma pneumoniae as well as Mycoplasma genitalium. Among the most likely participants of this machinery are homologs of the Holliday junction migration motor protein RuvB. In both M. pneumoniae and M. genitalium, genes have been identified that have the capacity to encode RuvB homologs (MPN536 and MG359, respectively). Here, the characteristics of the MPN536- and MG359-encoded proteins (the RuvB proteins from M. pneumoniae strain FH [RuvB(FH)] and M. genitalium [RuvB(Mge)], respectively) are described. Both RuvB(FH) and RuvB(Mge) were found to have ATPase activity and to bind DNA. In addition, both proteins displayed divalent cation- and ATP-dependent DNA helicase activity on partially double-stranded DNA substrates. The helicase activity of RuvB(Mge), however, was significantly lower than that of RuvB(FH). Interestingly, we found RuvB(FH) to be expressed exclusively by subtype 2 strains of M. pneumoniae. In strains belonging to the other major subtype (subtype 1), a version of the protein is expressed (the RuvB protein from M. pneumoniae strain M129 [RuvB(M129)]) that differs from RuvB(FH) in a single amino acid residue (at position 140). In contrast to RuvB(FH), RuvB(M129) displayed only marginal levels of DNA-unwinding activity. These results demonstrate that M. pneumoniae strains (as well as closely related Mycoplasma spp.) can differ significantly in the function of components of their DNA recombination and repair machinery.

  5. 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.

  6. Detection of mycoplasma contamination in cell cultures by a mycoplasma group-specific PCR.

    PubMed Central

    van Kuppeveld, F J; Johansson, K E; Galama, J M; Kissing, J; Bölske, G; van der Logt, J T; Melchers, W J

    1994-01-01

    The suitability of a 16S rRNA-based mycoplasma group-specific PCR for the detection of mycoplasma contamination in cell cultures was investigated. A total of 104 cell cultures were tested by using microbiological culture, DNA fluorochrome staining, DNA-rRNA hybridization, and PCR techniques. A comparison of the results obtained with these techniques revealed agreement for 95 cell cultures. Discrepant results, which were interpreted as false negative or false positive on the basis of a comparison with the results obtained with other methods, were observed with nine cell cultures. The microbiological culture technique produced false-negative results for four cell cultures. The hybridization technique produced false-negative results for two cell cultures, and for one of these cell cultures the DNA staining technique also produced a false-negative result. The PCR may have produced false-positive results for one cell culture. Ambiguous results were obtained with the remaining two cell cultures. Furthermore, the presence of contaminating bacteria interfered with the interpretation of the DNA staining results for 16 cell cultures. For the same reason the hybridization signals of nine cell cultures could not be interpreted. Our results demonstrate the drawbacks of each of the detection methods and the suitability of the PCR for the detection of mycoplasmas in cell cultures. PMID:7509584

  7. Comparison of the illumigene Mycoplasma DNA Amplification Assay and Culture for Detection of Mycoplasma pneumoniae

    PubMed Central

    Ratliff, Amy E.; Duffy, Lynn B.

    2014-01-01

    A loop-mediated isothermal amplification (LAMP) system, the illumigene Mycoplasma DNA amplification assay (Meridian Bioscience, Inc., Cincinnati, OH) was evaluated to determine its analytical sensitivity, specificity, and clinical application in comparison to historic culture in a collection of archived respiratory specimens. The illumigene limit of detection was ≤88 CFU/reaction for 10 Mycoplasma pneumoniae reference strains. This assay correctly identified 36 M. pneumoniae reference strains and clinical isolates from various geographic origins, including both of the main subtypes. No cross-reactions were detected with other mycoplasmas, ureaplasmas, other bacterial species, viruses, yeasts, or human DNA. Among 214 respiratory specimens previously cultured for M. pneumoniae, when real-time PCR with bidirectional sequencing of the PCR products was used to resolve discrepancies, the sensitivity was 22 of 22 (100%) and the specificity was 190 of 192 (99%). This commercial LAMP assay is a useful rapid method for detecting M. pneumoniae in clinical specimens. Additional prospective clinical trials with direct comparison to culture and PCR are warranted. PMID:24430454

  8. Mycoplasma insons sp. nov., a twisted mycoplasma from green iguanas (Iguana iguana).

    PubMed

    May, Meghan; Ortiz, G Javier; Wendland, Lori D; Rotstein, David S; Relich, Ryan F; Balish, Mitchell F; Brown, Daniel R

    2007-09-01

    Mycoplasma insons sp. nov., first cultured from the choanae and tracheae of healthy green iguanas (Iguana iguana) from El Salvador, was readily distinguished from all previously described mollicutes and assigned to the Mycoplasma fastidiosum phylogenetic cluster by 16S rRNA gene sequence comparisons. Growth inhibition assays distinguished the isolates serologically from the other two members of that cluster. Many M. insons cells exhibit a remarkable twisted rod morphology despite lacking a cell wall. The organism is nonmotile, produces acid from glucose, but does not hydrolyze arginine, esculin, or urea. Mycoplasma insons 16S rRNA gene was also detected by PCR in packed blood cells from culture-negative iguanas. The type strain I17P1(T) has been deposited with the Mollicutes Collection at Purdue University and with the American Type Culture Collection (ATCC BAA-1435) in the USA. A limited number of cultures generated by the authors have also been deposited with the Culture Collection, University of Göteborg, in Sweden (CCUG 53461).

  9. 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.

  10. 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

  11. Mycoplasma Removal from Cell Culture Using Antimicrobial Photodynamic Therapy

    PubMed Central

    Hasebe, Akira; Ishikawa, Isao; Shamsul, Haque M.; Ohtani, Makoto; Segawa, Taku; Saeki, Ayumi; Tanizume, Naoho; Oouchi, Manabu; Okagami, Yoshihide; Okano, Teruo

    2013-01-01

    Abstract Objective: The objective of this research was to determine the effectiveness of antimicrobial photodynamic therapy (aPDT) in the removal of mycoplasmas from contaminated cells. Background data: Mycoplasmas often contaminate cell cultures. The cell-contaminating mycoplasmas are removed by antibiotics, but the use of antibiotics usually induces antibiotic-resistant bacteria. aPDT is expected to be a possible alternative to antibiotic treatments for suppressing infections. Materials and Methods: Mycoplasma salivarium (Ms)-infected human embryonic kidney (HEK) 293 cells were irradiated using a red light-emitting diode (LED) in the presence of methylene blue (MB) as a photosensitizer. The Ms viable count was determined using culture on agar plates or using a mycoplasma detection kit. Results: aPDT performed using red LED irradiation was effective in decreasing live Ms in the presence of MB without damaging the HEK293 cells. aPDT removed live Ms from the infected cells after washing the cells with sterilized phosphate-buffered saline (PBS) to decrease the initial number of live Ms before aPDT. Conclusions: This study suggests that aPDT could remove mycoplasmas from contaminated cells. PMID:23402393

  12. 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

  13. 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.

  14. 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

  15. Immunological characterization of Mycoplasma hyopneumoniae recombinant proteins.

    PubMed

    Simionatto, Simone; Marchioro, Silvana B; Galli, Vanessa; Brum, Clarice B; Klein, Catia S; Rebelatto, Raquel; Silva, Everton F; Borsuk, Sibele; Conceição, Fabricio R; Dellagostin, Odir A

    2012-03-01

    Mycoplasma hyopneumoniae, the primary pathogen of enzootic pneumonia, is highly prevalent worldwide and causes major economic losses to the pig industry. Commercial vaccines are widely used in the control of this disease, however, they provide only partial protection. The aim of this study was to evaluate 34 recombinant proteins of M. hyopneumoniae expressed in Escherichia coli. Antigenic and immunogenic properties of these proteins were analyzed. For this, the proteins were tested against hyperimmune and convalescent pig sera through ELISA and Western blot. Immunogenicity of the recombinant proteins was evaluated in BALB/c mice following intramuscular inoculation. Most antigens were able to induce a strong immune response and sera from inoculated mice were able to recognize native proteins by cell ELISA and Western blot. Several recombinant proteins were specifically recognized by convalescent pig sera, indicating they are expressed during infection. These data may help to develop more efficacious vaccines against M. hyopneumoniae.

  16. Mycoplasma hyopneumoniae: from disease to vaccine development.

    PubMed

    Simionatto, Simone; Marchioro, Silvana Beutinger; Maes, Dominiek; Dellagostin, Odir Antônio

    2013-08-30

    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. Despite efforts to control M. hyopneumoniae infection, significant economic losses in pig production continue to occur. The results of genome-based research have the potential to help understand the biology and pathogenesis of M. hyopneumoniae, and contribute to the development of more effective vaccines and diagnostic tests. In this review, the characteristics of M. hyopneumoniae related to pathogenesis and control measures will be discussed. Special emphasis will be placed on vaccination strategies that have been proposed with the use of reverse vaccinology approaches.

  17. 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.

  18. 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

  19. Glide: a new approach for rapid, accurate docking and scoring. 2. Enrichment factors in database screening.

    PubMed

    Halgren, Thomas A; Murphy, Robert B; Friesner, Richard A; Beard, Hege S; Frye, Leah L; Pollard, W Thomas; Banks, Jay L

    2004-03-25

    Glide's ability to identify active compounds in a database screen is characterized by applying Glide to a diverse set of nine protein receptors. In many cases, two, or even three, protein sites are employed to probe the sensitivity of the results to the site geometry. To make the database screens as realistic as possible, the screens use sets of "druglike" decoy ligands that have been selected to be representative of what we believe is likely to be found in the compound collection of a pharmaceutical or biotechnology company. Results are presented for releases 1.8, 2.0, and 2.5 of Glide. The comparisons show that average measures for both "early" and "global" enrichment for Glide 2.5 are 3 times higher than for Glide 1.8 and more than 2 times higher than for Glide 2.0 because of better results for the least well-handled screens. This improvement in enrichment stems largely from the better balance of the more widely parametrized GlideScore 2.5 function and the inclusion of terms that penalize ligand-protein interactions that violate established principles of physical chemistry, particularly as it concerns the exposure to solvent of charged protein and ligand groups. Comparisons to results for the thymidine kinase and estrogen receptors published by Rognan and co-workers (J. Med. Chem. 2000, 43, 4759-4767) show that Glide 2.5 performs better than GOLD 1.1, FlexX 1.8, or DOCK 4.01.

  20. 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

  1. 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.

  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. 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

  4. 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.

  5. Novel approach for designing a hypersonic gliding-cruising dual waverider vehicle

    NASA Astrophysics Data System (ADS)

    Liu, Jun; Ding, Feng; Huang, Wei; Jin, Liang

    2014-09-01

    For a hypersonic gliding-cruising vehicle, the gliding Mach number is larger than the cruising Mach number. It may be useful to design the inlet shroud to act as the compression surface of the waverider, to ensure that the vehicle rides on the shock wave, during both the gliding and cruising phases. A new design concept, namely a gliding-cruising dual waverider, is proposed in the current study. During the gliding phase, the hypersonic vehicle rides on the shock wave at the design gliding Mach number, as the inlet shroud is designed to act as waverider's compression surface. During the cruising phase, when the inlet shroud is cast away or jettisoned, the hypersonic vehicle rides on the shock wave at the design cruising Mach number, as the forebody is designed to act as waverider's compression surface. Thus, the design methodology of the dual-cone-derived waverider is described based on the theory of conical flow. Finally, the numerical methods are utilized to verify the new design method of the aerodynamic configuration. This methodology proposed is useful to design a hypersonic vehicle for two regimes of flight.

  6. Hemotropic mycoplasma in a free-ranging black howler monkey (Alouatta caraya) in Brazil.

    PubMed

    Santos, Leonilda C; Cubilla, Michelle P; de Moraes, Wanderlei; Cubas, Zalmir S; Oliveira, Marcos J; Estrada, Marko; Leutenegger, Christian M; Sykes, Jane E; Lindsay, Leann L; Marcondes, Mary; Barros Filho, Ivan R; Biondo, Alexander W

    2013-07-01

    Hemotropic mycoplasmas are bacteria that infect erythrocytes and cause subclinical infections to life-threatening disease. We describe hemotropic mycoplasma infection in a free-ranging black howler monkey (Alouatta caraya). This is the first molecular detection of a hemotropic mycoplasma in a nonhuman primate from Brazil.

  7. Transition of dislocation glide to shear transformation in shocked tantalum

    DOE PAGES

    Hsiung, Luke L.; Campbell, Geoffrey H.

    2017-02-28

    A TEM study of pure tantalum and tantalum-tungsten alloys explosively shocked at a peak pressure of 30 GPa (strain rate: ~1 x 104 sec-1) is presented. While no ω (hexagonal) phase was found in shock-recovered pure Ta and Ta-5W that contain mainly a low-energy cellular dislocation structure, shock-induced ω phase was found to form in Ta-10W that contains evenly distributed dislocations with a stored dislocation density higher than 1 x 1012 cm-2. The TEM results clearly reveal that shock-induced α (bcc) → ω (hexagonal) shear transformation occurs when dynamic recovery reactions which lead the formation low-energy cellular dislocation structure becomemore » largely suppressed in Ta-10W shocked under dynamic (i.e., high strain-rate and high-pressure) conditions. A novel dislocation-based mechanism is proposed to rationalize the transition of dislocation glide to twinning and/or shear transformation in shock-deformed tantalum. Lastly, twinning and/or shear transformation take place as an alternative deformation mechanism to accommodate high-strain-rate straining when the shear stress required for dislocation multiplication exceeds the threshold shear stresses for twinning and/or shear transformation.« less

  8. 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.

  9. Coupled gas flow-plasma model for a gliding arc: investigations of the back-breakdown phenomenon and its effect on the gliding arc characteristics

    NASA Astrophysics Data System (ADS)

    Sun, S. R.; Kolev, St.; Wang, H. X.; Bogaerts, A.

    2017-01-01

    We present a 3D and 2D Cartesian quasi-neutral plasma model for a low current argon gliding arc discharge, including strong interactions between the gas flow and arc plasma column. The 3D model is applied only for a short time of 0.2 ms due to its huge computational cost. It mainly serves to verify the reliability of the 2D model. As the results in 2D compare well with those in 3D, they can be used for a better understanding of the gliding arc basic characteristics. More specifically, we investigate the back-breakdown phenomenon induced by an artificially controlled plasma channel, and we discuss its effect on the gliding arc characteristics. The back-breakdown phenomenon, or backward-jump motion of the arc, as observed in the experiments, results in a drop of the gas temperature, as well as in a delay of the arc velocity with respect to the gas flow velocity, allowing more gas to pass through the arc, and thus increasing the efficiency of the gliding arc for gas treatment applications.

  10. Survival and replication of Mycoplasma species in recycled bedding sand and association with mastitis on dairy farms in Utah.

    PubMed

    Justice-Allen, A; Trujillo, J; Corbett, R; Harding, R; Goodell, G; Wilson, D

    2010-01-01

    Mycoplasma spp., usually Mycoplasma bovis, are important bovine pathogens that can cause mastitis, metritis, pneumonia, and arthritis. The currently documented routes of transmission of Mycoplasma spp. are through contaminated milking equipment and by direct animal contact. The existence of environmental sources for Mycoplasma spp. and their role in transmission and clinical disease is poorly characterized. Mycoplasma spp. (confirmed as M. bovis in 2 of 4 samples tested using PCR) was found in recycled bedding sand originating from a dairy experiencing an outbreak of clinical mycoplasma mastitis. Mycoplasma spp. were subsequently found in bedding sand from 2 other dairies whose bulk-tank milk was mycoplasma-positive. The association between the occurrence of Mycoplasma spp. in recycled bedding sand and mycoplasma mastitis in cows was further investigated using a pile of recycled sand from dairy 1. Study objectives included the determination of factors associated with the concentration of Mycoplasma spp. in recycled bedding sand and the duration of survival of mycoplasmas in the sand. We also evaluated the efficacy of 2 disinfectants at 2 different concentrations each for the elimination of Mycoplasma spp. from contaminated sand. Mycoplasma spp. survived in the sand pile for 8 mo. The concentration of Mycoplasma spp. within the sand pile was directly related to temperature and precipitation. It was also positively associated with the growth of gram-negative microorganisms, suggesting the possibility of the formation of a biofilm. Ideal temperatures for replication of Mycoplasma spp. occurred between 15 and 20 degrees C. Moisture in the sand and movement of the sand pile also appeared to play a role in replication of mycoplasmas. We found that 0.5% sodium hypochlorite or 2% chlorhexidine were efficacious in eliminating Mycoplasma spp. from contaminated bedding sand. Recycled bedding sand could be an environmental source of Mycoplasma spp., including M. bovis

  11. 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.

  12. 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

  13. 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.

  14. EPS-I Polysaccharide Protects Mycoplasma pulmonis from Phagocytosis

    PubMed Central

    Shaw, Brandon M.; Daubenspeck, James M.; Simmons, Warren L.; Dybvig, Kevin

    2012-01-01

    Few mycoplasmal polysaccharides have been described and little is known about their role in pathogenesis. The infection of mice with Mycoplasma pulmonis has been utilized in many in vivo and in vitro studies to gain a better understanding of host-pathogen interactions during chronic respiratory infection. Although alveolar macrophages have a primary role in host defense, M. pulmonis is killed inefficiently in vitro. One antiphagocytic factor produced by the mycoplasma is the family of phase- and size-variable Vsa lipoproteins. However, bacteria generally employ multiple strategies for combating host defenses, with capsular polysaccharide often having a key role. We show here that mutants lacking the EPS-I polysaccharide of M. pulmonis exhibit increased susceptibility to binding and subsequent killing by alveolar macrophages. These results give further insight into how mycoplasmas are able to avoid the host immune system and sustain a chronic infection. PMID:23190331

  15. Occurrence of Urease in T Strains of Mycoplasma

    PubMed Central

    Shepard, Maurice C.; Lunceford, Carl D.

    1967-01-01

    A previously unknown metabolite necessary for growth of T strains of Mycoplasma in artificial culture media has been identified as urea. The source of this metabolite was the mammalian plasma or serum enrichment of the culture medium. Normal horse serum was the most satisfactory native protein enrichment for cultivation of T strains of mycoplasma, and it is believed that its superior performance in agar and fluid culture media is associated with its relatively high urea content (approximately 40 mg/100 ml). T-strain urease activity was maximal at pH 6.0 ± 0.5. This is also the optimal pH for growth of T strains. Substrate concentrations greater than 1.0% urea were inhibitory to growth and urease activity of T-strain organisms, and optimal urea concentrations in fluid media appeared to lie within the range of 0.008 to 0.01 m. This range of urea concentration permitted maximal growth of T-strain organisms without rapid loss of viability due to excessive ammonia accumulation and rise in pH to lethal levels. T strains of Mycoplasma were cultivated in a serum-free fluid medium containing urea as the only added metabolite and nitrogen source. T strains are the only known human mycoplasmas which exhibit urease activity, and this biochemical marker can be employed as an aid in the detection and identification of T strains of Mycoplasma (urease color test) and in distinguishing T strains from other members of the human Mycoplasma group. PMID:6025439

  16. Gliding resistance of flexor tendon associated with carpal tunnel pressure: a biomechanical cadaver study.

    PubMed

    Zhao, Chunfeng; Ettema, Anke M; Berglund, Lawrence J; An, Kai-Nan; Amadio, Peter C

    2011-01-01

    The purpose of this study was to investigate the effect of carpal tunnel pressure on the gliding characteristics of flexor tendons within the carpal tunnel. Eight fresh human cadaver wrists and hands were used. A balloon was inserted into the carpal tunnel to elevate the pressure. The mean gliding resistance of the middle finger flexor digitorum superficialis tendon was measured with the following six conditions: (1) as a baseline, before balloon insertion; (2) balloon with 0 mmHg pressure; (3) 30 mmHg; (4) 60 mmHg; (5) 90 mmHg; (6) 120 mmHg. The gliding resistance of flexor tendon gradually increased as the carpal tunnel pressure was elevated. At pressures above 60 mmHg, the increase in gliding resistance became significant compared to the baseline condition. This study helps us to understand the relationship between carpal tunnel pressure, which is elevated in the patient with carpal tunnel syndrome (CTS) and tendon gliding resistance, which is a component of the work of flexion. These findings suggest that patients with CTS may have to expend more energy to accomplish specific motions, which may in turn affect symptoms of hand pain, weakness and fatigue, seen commonly in such patients.

  17. Transposon insertions in the Flavobacterium johnsoniae ftsX gene disrupt gliding motility and cell division.

    PubMed

    Kempf, M J; McBride, M J

    2000-03-01

    Flavobacterium johnsoniae is a gram-negative bacterium that exhibits gliding motility. To determine the mechanism of flavobacterial gliding motility, we isolated 33 nongliding mutants by Tn4351 mutagenesis. Seventeen of these mutants exhibited filamentous cell morphology. The region of DNA surrounding the transposon insertion in the filamentous mutant CJ101-207 was cloned and sequenced. The transposon was inserted in a gene that was similar to Escherichia coli ftsX. Two of the remaining 16 filamentous mutants also carried insertions in ftsX. Introduction of the wild-type F. johnsoniae ftsX gene restored motility and normal cell morphology to each of the three ftsX mutants. CJ101-207 appears to be blocked at a late stage of cell division, since the filaments produced cross walls but cells failed to separate. In E. coli, FtsX is thought to function with FtsE in translocating proteins involved in potassium transport, and perhaps proteins involved in cell division, into the cytoplasmic membrane. Mutations in F. johnsoniae ftsX may prevent translocation of proteins involved in cell division and proteins involved in gliding motility into the cytoplasmic membrane, thus resulting in defects in both processes. Alternatively, the loss of gliding motility may be an indirect result of the defect in cell division. The inability to complete cell division may alter the cell architecture and disrupt gliding motility by preventing the synthesis, assembly, or functioning of the motility apparatus.

  18. Tissue sequestration of 'Candidatus Mycoplasma turicensis'.

    PubMed

    Novacco, Marilisa; Riond, Barbara; Meli, Marina L; Grest, Paula; Hofmann-Lehmann, Regina

    2013-12-27

    'Candidatus Mycoplasma turicensis' ('Candidatus M. turicensis') is a hemoplasma species that infects felids. It differs from other feline hemoplasma species due to its particular infection kinetics and phylogenetic similarity to rodent hemoplasma species. The lower and shorter bacteremia produced by 'Candidatus M. turicensis' suggests a possible tissue sequestration of the organism. The aim of this study was to explore this possibility. Five specified-pathogen free cats were subcutaneously inoculated with 'Candidatus M. turicensis' and sacrificed 86 days after inoculation. Thirty-one selected organs were collected upon necropsy, and samples were analyzed by real-time Taqman(®) PCR. The humoral immune response was monitored by DnaK ELISA. All five cats had detectable 'Candidatus M. turicensis' loads in the majority (52-100%) of the tested tissues. High 'Candidatus M. turicensis' tissue loads (average 3.46×10(4) copies/10 mg) were detected in the samples. The presence of the organisms in the tissues could not be explained by the blood burdens because the blood of four out of five cats tested PCR-negative at the time of necropsy. This is the first study to describe the distribution of 'Candidatus M. turicensis' in various organs; it also demonstrates that, in contrast to other feline hemoplasma species, significant sequestration of 'Candidatus M. turicensis' occurs in many tissues. These results represent an important step toward the understanding of the pathogenesis of 'Candidatus M. turicensis'.

  19. 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.

  20. Mycoplasma genitalium: An Emerging Sexually Transmitted Infection.

    PubMed

    Munoz, Jessian L; Goje, Oluwatosin Jaiyeoba

    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.

  1. Mycoplasma genitalium, an emerging sexually transmitted pathogen.

    PubMed

    Cazanave, C; Manhart, L E; Bébéar, C

    2012-09-01

    Mycoplasma genitalium is a sexually transmitted organism associated with non-gonococcal urethritis in men and several inflammatory reproductive tract syndromes in women such as cervicitis, pelvic inflammatory disease, and infertility. There was evidence for an association of M. genitalium with endometritis and pelvic inflammatory disease (PID), but additional studies are necessary to confirm this. The evidence as to whether M. genitalium can cause adverse pregnancy outcomes such as preterm labor is conflicting. But the authors of some studies on M. genitalium as a cause of infertility have reported this association. This species is very difficult to culture; thus, nucleic acid amplification testing is the only method available for M. genitalium detection. The lack of a cell wall makes M. genitalium intrinsically resistant to antibiotics acting at this level, such as beta-lactams. The treatment of M. genitalium infections is not standardized. Macrolides are recommended, especially single-dose azithromycin; tetracyclines are responsible for a great number of therapeutic failures even no resistance mechanism has yet been demonstrated. Acquired resistance to macrolides and fluoroquinolones leading to therapeutic failure has also been reported. All this raises the issue of the most appropriate therapeutic management and requires drafting diagnostic and therapeutic guidelines for the treatment of M. genitalium infections.

  2. Selective medium for culture of Mycoplasma hyopneumoniae.

    PubMed

    Cook, Beth S; Beddow, Jessica G; Manso-Silván, Lucía; Maglennon, Gareth A; Rycroft, Andrew N

    2016-11-15

    The fastidious porcine respiratory pathogen Mycoplasma hyopneumoniae has proven difficult to culture since it was first isolated in 1965. A reliable solid medium has been particularly challenging. Moreover, clinical and pathological samples often contain the fast-growing M. hyorhinis which contaminates and overgrows M. hyopneumoniae in primary culture. The aim of this study was to optimise the culture medium for recovery of M. hyopneumoniae and to devise a medium for selection of M. hyopneumoniae from clinical samples also containing M. hyorhinis. The solid medium devised by Niels Friis was improved by use of Purified agar and incorporation of DEAE-dextran. Addition of glucose or neutralization of acidity in liquid medium with NaOH did not improve the final yield of viable organisms or alter the timing of peak viability. Analysis of the relative susceptibility of M. hyopneumoniae and M. hyorhinis strains to four antimicrobials showed that M. hyopneumoniae is less susceptible than M. hyorhinis to kanamycin. This was consistent in all UK and Danish strains tested. A concentration of 2μg/ml of kanamycin selectively inhibited the growth of all M. hyorhinis tested, while M. hyopneumoniae was able to grow. This forms the basis of an effective selective culture medium for M. hyopneumoniae.

  3. Proposal for 'Candidatus Mycoplasma haemomuris subsp. musculi' in mice, and 'Candidatus Mycoplasma haemomuris subsp. ratti' in rats.

    PubMed

    Harasawa, Ryô; Fujita, Hiromi; Kadosaka, Teruki; Ando, Shuji; Rikihisa, Yasuko

    2015-02-01

    Mycoplasma haemomuris is causative of infectious anaemia or splenomegaly in rodents. We examined the nucleotide sequences of the non-ribosomal genes, rnpB and dnaK, in strains of the species M. haemomuris detected in small field mice and black rats. rnpB nucleotide sequences in strains of the species M. haemomuris isolated from small field mice and black rats had only 89 % sequence similarity, suggesting their separation into two distinct subgroups. dnaK had a nucleotide sequence similarity of 84 % between the subgroups. These results support the classification of M. haemomuris into two genetically distinct subgroups. Here we propose the establishment of these subgroups as 'Candidatus Mycoplasma haemomuris subsp. musculi', detected in small field mice (Apodemus argenteus), and 'Candidatus Mycoplasma haemomuris subsp. ratti', detected in black rats (Rattus rattus).

  4. Nanotransformation of the haemotrophic Mycoplasma suis during in vitro cultivation attempts using modified cell free Mycoplasma media.

    PubMed

    Schreiner, Sabrina A; Hoelzle, Katharina; Hofmann-Lehmann, Regina; Hamburger, Anja; Wittenbrink, Max M; Kramer, Manuela M; Sokoli, Albina; Felder, Kathrin M; Groebel, Katrin; Hoelzle, Ludwig E

    2012-11-09

    Mycoplasma suis belongs to haemotrophic mycoplasmas (HMs) which cause infectious anaemia in a large variety of mammals. To date, no in vitro cultivation system for M. suis or other HMs has been established. We hypothesised that M. suis could grow in classical Mycoplasma media supplemented with nutrients (e.g. glucose, iron-binding proteins) which are naturally available from its host environment, the porcine blood. Blood from experimentally M. suis-infected pigs was used to inoculate either standard SP-4 Mycoplasma medium supplemented with iron-binding proteins (transferrin, haemin, and haemoglobin) or glucose-enriched Hayflick Mycoplasma medium. A quantitative M. suis-specific real-time PCR assay was applied to determine and quantify M. suis loads weekly during 12 week-incubation. The first 2 weeks after inoculation M. suis loads decreased remarkably and then persisted at a stationary level over the observation time of 12 weeks in iron-binding protein- or glucose supplemented media variants. Scanning electron microscopic analysis of liquid M. suis sub-cultures on Hayflick agar showed small, densely-packed microcolonies of irregular M. suis cells of reduced size (0.2-0.6μm) indicating nanotransformation. The partial 16S rDNA sequence of these cultured M. suis nanocells was 99.9% identical to M. suis. M. suis cells derived from liquid cultures interact in vitro with porcine erythrocytes by fibril-like structures. We conclude, that the modified Mycoplasma media used for M. suis cultivation are obviously unfavourable for growth but lead to culture persistence. M. suis adapt to inappropriate culture conditions by alteration into nanoforms.

  5. A novel rapid DNA microarray assay enables identification of 37 Mycoplasma species and highlights multiple Mycoplasma infections.

    PubMed

    Schnee, Christiane; Schulsse, Samuel; Hotzel, Helmut; Ayling, Roger D; Nicholas, Robin A J; Schubert, Evelyn; Heller, Martin; Ehricht, Ralf; Sachse, Konrad

    2012-01-01

    Mycoplasmas comprise a conglomerate of pathogens and commensals occurring in humans and animals. The genus Mycoplasma alone contains more than 120 species at present, and new members are continuously being discovered. Therefore, it seems promising to use a single highly parallel detection assay rather than develop separate tests for each individual species. In this study, we have designed a DNA microarray carrying 70 oligonucleotide probes derived from the 23S rRNA gene and 86 probes from the tuf gene target regions. Following a PCR amplification and biotinylation step, hybridization on the array was shown to specifically identify 31 Mycoplasma spp., as well as 3 Acholeplasma spp. and 3 Ureaplasma spp. Members of the Mycoplasma mycoides cluster can be recognized at subgroup level. This procedure enables parallel detection of Mollicutes spp. occurring in humans, animals or cell culture, from mono- and multiple infections, in a single run. The main advantages of the microarray assay include ease of operation, rapidity, high information content, and affordability. The new test's analytical sensitivity is equivalent to that of real-time PCR and allows examination of field samples without the need for culture. When 60 field samples from ruminants and birds previously analyzed by denaturing-gradient gel electrophoresis (DGGE) were tested by the microarray assay both tests identified the same agent in 98.3% of the cases. Notably, microarray testing revealed an unexpectedly high proportion (35%) of multiple mycoplasma infections, i.e., substantially more than DGGE (15%). Two of the samples were found to contain four different Mycoplasma spp. This phenomenon deserves more attention, particularly its implications for epidemiology and treatment.

  6. Anatomic location of Mycoplasma mycoides subsp. capri and Mycoplasma agalactiae in naturally infected goat male auricular carriers.

    PubMed

    Gómez-Martín, Angel; De la Fe, Christian; Amores, Joaquín; Sánchez, Antonio; Contreras, Antonio; Paterna, Ana; Buendía, Antonio J; Corrales, Juan C

    2012-06-15

    This study sought to determine whether male goat auricular carriers of mycoplasmas known to cause contagious agalactia could harbour these microorganisms at anatomical sites other than the ears. A microbiological study was conducted in 6 naturally infected bucks that had been diagnosed as chronic auricular asymptomatic carriers of Mycoplasma (M.) mycoides subsp. capri (Mmc) more than one year previously. To detect mycoplasmas, cultures and PCR were performed on 46 samples taken from each goat from the cardio-respiratory, digestive, nervous, lymph and genitourinary systems and several joints. Of a total of 274 samples analyzed, 28 were positive for mycoplasmas (10.1%): Mmc was detected in 17 (6.1%), Mycoplasma (M.) agalactiae in 12 (4.3%) and both microorganisms were identified in one of the samples. In all 6 goats, mixed infection was observed despite none being auricular carriers of M. agalactiae. Mycoplasma spp. were identified at 15 different sites; the most frequent sites being the joints (31.2%, 5 positive samples), lymph nodes (25%, 4 positive samples) and respiratory tract (25%, 4 positive samples). Positive results were also obtained in three brain tissue (18.7%), two cardiac tissue (12.5%) and one ileum, urethra, testicle and bulbourethral gland (6.25%) samples. The histopathological findings may suggest the presence of mild chronic conditions in some of the organs where the bacteria were found. Our findings reveal for the first time the capacity of Mmc and M. agalactiae to colonize several other organ systems in chronically naturally infected auricular carriers, possibly representing an added risk factor for the spread of these microorganisms. In the case of M. agalactiae, colonization seemed to be independent of the animal's auricular carrier state.

  7. Effect of 2H and 18O water isotopes in kinesin-1 gliding assay

    PubMed Central

    Herskowitz, Lawrence J.; Koch, Steven J.

    2014-01-01

    We show for the first time the effects of heavy-hydrogen water (2H2O) and heavy-oxygen water (H218O) on the gliding speed of microtubules on kinesin-1 coated surfaces. Increased fractions of isotopic waters used in the motility solution decreased the gliding speed of microtubules by a maximum of 21% for heavy-hydrogen and 5% for heavy-oxygen water. We also show that gliding microtubule speed returns to its original speed after being treated with heavy-hydrogen water. We discuss possible interpretations of these results and the importance for future studies of water effects on kinesin and microtubules. We also discuss the implication for using heavy waters in biomolecular devices incorporating molecular motors. PMID:24711961

  8. 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.

  9. Identification of Mycoplasma bovigenitalium and Mycoplasma canadense from outbreaks of granulopapular vulvovaginitis in dairy cattle in Israel.

    PubMed

    Lysnyansky, I; Brenner, J; Alpert, N; Benjamin, A; Bernstein, M; Elad, D; Blum, S; Friedgut, O; Rotenberg, D

    2009-09-12

    A syndrome in which white foci and granulopustular lesions appeared on the vaginal mucous membranes of Holstein cows in several dairy herds in Israel is described. During clinical and diagnostic investigations, Mycoplasma bovigenitalium was isolated from 11 of 20 clinical cases. Vaginal swabs taken from the same cows yielded three isolates of Mycoplasma canadense, which were all associated with the M bovigenitalium infection. Two isolates of small, round, non-enveloped viral particles were approximately 25 nm in diameter and characteristic of enteroviruses on negative-staining electron microscopy.

  10. 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

  11. CO2 conversion in a gliding arc plasma: 1D cylindrical discharge model

    NASA Astrophysics Data System (ADS)

    Wang, Weizong; Berthelot, Antonin; Kolev, Stanimir; Tu, Xin; Bogaerts, Annemie

    2016-12-01

    CO2 conversion by a gliding arc plasma is gaining increasing interest, but the underlying mechanisms for an energy-efficient process are still far from understood. Indeed, the chemical complexity of the non-equilibrium plasma poses a challenge for plasma modeling due to the huge computational load. In this paper, a one-dimensional (1D) gliding arc model is developed in a cylindrical frame, with a detailed non-equilibrium CO2 plasma chemistry set, including the CO2 vibrational kinetics up to the dissociation limit. The model solves a set of time-dependent continuity equations based on the chemical reactions, as well as the electron energy balance equation, and it assumes quasi-neutrality in the plasma. The loss of plasma species and heat due to convection by the transverse gas flow is accounted for by using a characteristic frequency of convective cooling, which depends on the gliding arc radius, the relative velocity of the gas flow with respect to the arc and on the arc elongation rate. The calculated values for plasma density and plasma temperature within this work are comparable with experimental data on gliding arc plasma reactors in the literature. Our calculation results indicate that excitation to the vibrational levels promotes efficient dissociation in the gliding arc, and this is consistent with experimental investigations of the gliding arc based CO2 conversion in the literature. Additionally, the dissociation of CO2 through collisions with O atoms has the largest contribution to CO2 splitting under the conditions studied. In addition to the above results, we also demonstrate that lumping the CO2 vibrational states can bring a significant reduction of the computational load. The latter opens up the way for 2D or 3D models with an accurate description of the CO2 vibrational kinetics.

  12. Phospholipid composition of gliding bacteria: oral isolates of Capnocytophaga compared with Sporocytophaga.

    PubMed Central

    Holt, S C; Doundowlakis, J; Takacs, B J

    1979-01-01

    The distribution of acetone-soluble (neutral glycolipid) and acetone-insoluble (phospholipid isoprenoids) lipids in oral isolates of gram-negative gliding bacteria of the genus Capnocytophaga was compared with those in a non-host-related gliding bacterium, Sporocytophaga myxococcoides. The acetone-soluble material accounted for 34 to 55% of the extracted lipids; the remainder was acetone-insoluble material. The major phospholipid was phosphatidylethanolamine (67%), with lesser amounts of lysophosphatidylethanolamine and several unidentified phosphate-containing compounds. Capnocytophaga also contained significant amounts of an ornithine-amino lipid. PMID:500209

  13. Gliding arc surface modification of carrot nanofibre coating - perspective for composite processing

    NASA Astrophysics Data System (ADS)

    Kusano, Y.; Berglund, L.; Aitomäki, Y.; Oksman, K.; Madsen, B.

    2016-07-01

    Surfaces of carrot nanofibre coatings were modified by a gliding arc in atmospheric pressure air. The treatment strengthened wetting of deionized water and glycerol, increased an oxygen content, C-O and C=O, and moderately roughened the surfaces. In the perspective of composite materials, these changes to the nanofibres can potentially improve their processability when they are to be impregnated with a polymeric matrix. However, longer exposure to the gliding arc reduced oxidation and roughness of the surface, and thus there exists an optimum condition to achieve good wetting to solvents.

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. Rhabdomyolysis associated with antimicrobial drug-resistant Mycoplasma pneumoniae.

    PubMed

    Oishi, Tomohiro; Narita, Mitsuo; Ohya, Hitomi; Yamanaka, Takayuki; Aizawa, Yuta; Matsuo, Mai; Matsunaga, Masamichi; Tsukano, Shinya; Taguchi, Testuo

    2012-05-01

    We describe a case of rhabdomyolysis in a patient infected with antimicrobial drug-resistant Mycoplasma pneumoniae The patient's acute-phase serum levels of interleukin-18 and tumor necrosis factor-α were high, which suggests a pathogenic role for M. pneumoniae. In an era of increasing antimicrobial drug resistance, a system for rapidly identifying resistant M. pneumoniae would be beneficial.

  19. Macrolide susceptibility of Mycoplasma hyorhinis isolated from piglets.

    PubMed Central

    Kobayashi, H; Morozumi, T; Munthali, G; Mitani, K; Ito, N; Yamamoto, K

    1996-01-01

    Twenty strains of Mycoplasma hyorhinis were investigated for their in vitro susceptibilities to 15 antimicrobial agents by broth and agar dilution methods. Two of the 20 field strains showed low susceptibility to 14- and 16-membered macrolide antimicrobial agents tested. The two field strains were considered inducibly resistant to macrolides. PMID:8849222

  20. 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 ...

  1. Proteomic analysis of Mycoplasma gallisepticum vaccine strain F

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The persistence and displacement abilities of the Mycoplasma gallisepticum vaccine strain F (F-strain) are well documented. Understanding the mechanism(s) of colonization and persistence of F-strain will aid in the current intervention strategies to diagnose and control MG infections in poultry. In ...

  2. 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...

  3. High Prevalence of Mycoplasma faucium DNA in the Human Oropharynx.

    PubMed

    Edouard, Sophie; Courtois, Gaëlle Denis; Gautret, Philippe; Jouve, Jean-Luc; Minodier, Philippe; Noël, Guilhem; Roch, Antoine; Brouqui, Philippe; Stein, Andreas; Drancourt, Michel; Fournier, Pierre-Edouard; Raoult, Didier

    2016-01-01

    Mycoplasma faucium has recently been associated with brain abscesses and seems to originate from the mouth. We evaluated its prevalence by quantitative real-time PCR (qPCR) in the oropharynxes of 644 subjects and found that 25% harbored M. faucium, probably constituting the gateway for entrance of the bacteria into cerebral abscesses.

  4. Methyl-prednisolone in neurologic complications of Mycoplasma pneumonia.

    PubMed

    Gücüyener, K; Simşek, F; Yilmaz, O; Serdaroğlu, A

    2000-06-01

    In patients with Mycoplasma pneumonia extrapulmonary manifestations such as encephalitis, meningitis, cerebellar and brain stem involvement, cranial nerve lesions, peripheral neuropathy, polymyositis have been observed. We report a 16-year-old girl with M. pneumonia infection, acute behavioral changes and coma. Treatment with high dose methyl-prednisolone and clarithromycin led to rapid clinical improvement.

  5. Cranial neuropathy, myeloradiculopathy, and myositis: complications of Mycoplasma pneumoniae infection.

    PubMed

    Rothstein, T L; Kenny, G E

    1979-08-01

    Polymyositis, transverse myelitis, ascending polyneuritis, bilateral optic neuritis, and hearing loss developed in a patient with high complement-fixing antibody titers to Mycoplasma pneumoniae. Each of her three children had primary atypical pneumonia with isolation of the organism. The neurologic disturbance is thought to represent a postinfectious complication of M pneumoniae infection.

  6. Interaction of Mycoplasma dispar with bovine alveolar macrophages.

    PubMed Central

    Almeida, R A; Wannemuehler, M J; Rosenbusch, R F

    1992-01-01

    The capacity to avoid phagocytosis and the activation of bovine alveolar macrophages (BAM) by encapsulated Mycoplasma dispar or purified M. dispar capsule was investigated. Encapsulated and unencapsulated M. dispar were cocultured with BAM in the presence or absence of antisera prepared against unencapsulated M. dispar or purified capsule antiserum. Unopsonized mycoplasmas resisted phagocytosis, while only anti-capsule antibodies enhanced the phagocytosis of encapsulated mycoplasmas. BAM were cultured in the presence of purified M. dispar capsule or either live or heat-killed encapsulated or unencapsulated M. dispar. These BAM were then activated with Escherichia coli endotoxin or left without further activation. The supernatants of these cultures were assayed for tumor necrosis factor, interleukin 1, and glucose consumption as indicators of macrophage activation. Tumor necrosis factor and interleukin 1 were produced by BAM stimulated with unencapsulated M. dispar but not when encapsulated M. dispar or its purified capsule was used. Similarly, glucose consumption was increased in the presence of unencapsulated M. dispar, but not when BAM were cocultured with encapsulated M. dispar or purified capsule. When BAM were treated with purified capsule or encapsulated mycoplasmas, they could not be subsequently activated by endotoxin. These results indicate that encapsulated M. dispar or purified capsule exerts an inhibitory effect on the activity of BAM and prevents the activation of these cells. PMID:1612758

  7. High Prevalence of Mycoplasma faucium DNA in the Human Oropharynx

    PubMed Central

    Edouard, Sophie; Courtois, Gaëlle Denis; Gautret, Philippe; Jouve, Jean-Luc; Minodier, Philippe; Noël, Guilhem; Roch, Antoine; Brouqui, Philippe; Stein, Andreas; Drancourt, Michel; Fournier, Pierre-Edouard

    2015-01-01

    Mycoplasma faucium has recently been associated with brain abscesses and seems to originate from the mouth. We evaluated its prevalence by quantitative real-time PCR (qPCR) in the oropharynxes of 644 subjects and found that 25% harbored M. faucium, probably constituting the gateway for entrance of the bacteria into cerebral abscesses. PMID:26511735

  8. Atypical pneumonia associated with a Mycoplasma isolate in a kitten.

    PubMed

    Bongrand, Yannick; Blais, Marie-Claude; Alexander, Kate

    2012-10-01

    An atypical case of Mycoplasma pneumonia with an unusual radiographic and computed tomographic pattern was diagnosed in a Siamese kitten. The cat showed no response to broad-spectrum antibiotic therapy including enrofloxacin. The administration of doxycycline led to a dramatic clinical and radiographic improvement.

  9. Control of Mycoplasma hyopneumoniae infections in pigs.

    PubMed

    Maes, D; Segales, J; Meyns, T; Sibila, M; Pieters, M; Haesebrouck, F

    2008-01-25

    Mycoplasma hyopneumoniae, the primary pathogen of enzootic pneumonia, occurs worldwide and causes major economic losses to the pig industry. The organism adheres to and damages the ciliated epithelium of the respiratory tract. Affected pigs show chronic coughing, are more susceptible to other respiratory infections and have a reduced performance. Control of the disease can be accomplished in a number of ways. First, management practices and housing conditions in the herd should be optimized. These include all-in/all-out production, limiting factors that may destabilize herd immunity, maintaining optimal stocking densities, prevention of other respiratory diseases, and optimal housing and climatic conditions. Strategic medication with antimicrobials active against M. hyopneumoniae and, preferably, also against major secondary bacteria may be useful during periods when the pigs are at risk for respiratory disease. Finally, commercial bacterins are widely used to control M. hyopneumoniae infections. The main effects of vaccination include less clinical symptoms, lung lesions and medication use, and improved performance. However, bacterins provide only partial protection and do not prevent colonization of the organism. Different vaccination strategies (timing of vaccination, vaccination of sows, vaccination combined with antimicrobial medication) can be used, depending on the type of herd, the production system and management practices, the infection pattern and the preferences of the pig producer. Research on new vaccines is actively occurring, including aerosol and feed-based vaccines as well as subunit and DNA vaccines. Eradication of the infection at herd level based on age-segregation and medication is possible, but there is a permanent risk for re-infections.

  10. Marked colour divergence in the gliding membranes of a tropical lizard mirrors population differences in the colour of falling leaves.

    PubMed

    Klomp, D A; Stuart-Fox, D; Das, I; Ord, T J

    2014-12-01

    Populations of the Bornean gliding lizard, Draco cornutus, differ markedly in the colour of their gliding membranes. They also differ in local vegetation type (mangrove forest versus lowland rainforest) and consequently, the colour of falling leaves (red and brown/black in mangrove versus green, brown and black in rainforest). We show that the gliding membranes of these lizards closely match the colours of freshly fallen leaves in the local habitat as they appear to the visual system of birds (their probable predators). Furthermore, gliding membranes more closely resembled colours of local fallen leaves than standing foliage or fallen leaves in the other population's habitat. This suggests that the two populations have diverged in gliding membrane coloration to match the colours of their local falling leaves, and that mimicking falling leaves is an adaptation that functions to reduce predation by birds.

  11. 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

  12. Discrimination between Mycoplasma mycoides subsp. capri and Mycoplasma capricolum subsp. capricolum using PCR-RFLP and PCR.

    PubMed

    Cillara, Grazia; Manca, Maria Giovanna; Longheu, Carla; Tola, Sebastiana

    2015-09-01

    In this study, the dihydrolipoyl dehydrogenase (lpdA) gene was used to distinguish Mycoplasma mycoides subsp. capri (Mmc) from Mycoplasma capricolum subsp. capricolum (Mcc), two of four Mycoplasma species that cause contagious agalactia in sheep and goats. After alignment of nucleotide sequences of both species, specific primer sets were designed from unchanging and variable gene segments. The first primer set LPD-C1-F/LPD-C1-R was used to amplify a 911 bp fragment that was subsequently co-digested with FastDigest PstI, SspI, EcoRI and ClaI enzymes. The PCR-RFLP profiles differentiated the two mycoplasma species. The second primer set was used to distinguish Mmc from Mcc by single tube PCR. Both methods were further applied to identify 54 isolates collected from dairy herds from different provinces in Sardinia. The results of this study showed that PCR-RFLP and PCR could be used in routine diagnosis for rapid and specific simultaneous discrimination of Mmc and Mcc.

  13. 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.

  14. 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.

  15. Infection with hemotropic Mycoplasma species in patients with or without extensive arthropod or animal contact.

    PubMed

    Maggi, Ricardo G; Compton, Sarah M; Trull, Chelsea L; Mascarelli, Patricia E; Mozayeni, B Robert; Breitschwerdt, Edward B

    2013-10-01

    PCR amplification targeting the 16S rRNA gene was used to test individuals with and without extensive arthropod and animal contact for the possibility of hemotropic mycoplasma infection. The prevalence of hemotropic mycoplasma infection (4.7%) was significantly greater in previously reported cohorts of veterinarians, veterinary technicians, spouses of veterinary professionals, and others with extensive arthropod exposure and/or frequent animal contact than in a previously reported cohort of patients examined by a rheumatologist because of chronic joint pain or evidence of small-vessel disease (0.7%). Based upon DNA sequence analysis, a Mycoplasma ovis-like species was the most prevalent organism detected; however, infection with "Candidatus Mycoplasma haematoparvum" and a potentially novel, but incompletely characterized, hemotropic Mycoplasma species was also documented. Historical exposure to animals and arthropod vectors that can harbor hemotropic Mycoplasma spp. should be considered during epidemiological investigations and in the evaluation of individual patients.

  16. Novel hemotropic Mycoplasma species in white-tailed deer (Odocoileus virginianus).

    PubMed

    Maggi, Ricardo G; Chitwood, M Colter; Kennedy-Stoskopf, Suzanne; DePerno, Christopher S

    2013-12-01

    Globally, hemotropic Mycoplasma spp. are emerging or re-emerging zoonotic pathogens that affect livestock, wildlife, companion animals, and humans, potentially causing serious and economically important disease problems. Little is known about hemotropic Mycoplasma spp. prevalence, host-specificity, or route of transmission in most species, including wildlife. DNA amplification by PCR targeting the 16SrRNA and the RNaseP genes was used to establish the presence and prevalence of hemotropic Mycoplasma spp. in a white-tailed deer (O. virginianus) population in eastern North Carolina. Sixty-five deer (89%) tested positive for hemotropic Mycoplasma spp. where sequence analysis of the 16SsRNA and the RNaseP genes indicated the presence of at least three distinct species. This study represents the first detection of three distinct hemotropic Mycoplasma species in white-tailed deer and the first report of two novel hemotropic Mycoplasma species.

  17. Identification and purification of arginine deiminase that originated from Mycoplasma arginini.

    PubMed Central

    Sugimura, K; Fukuda, S; Wada, Y; Taniai, M; Suzuki, M; Kimura, T; Ohno, T; Yamamoto, K; Azuma, I

    1990-01-01

    A lymphocyte blastogenesis inhibitory factor, (LBIF), was purified from the culture supernatant of human histiocytic lymphoma U937 by fast protein liquid chromatography. In this study, we demonstrated, first, that LBIF originated from a mycoplasma, Mycoplasma arginini, infecting U937 cells, and second, that LBIF bore the arginine deiminase activity. The implication of in vivo immunosuppression induced by arginine-utilizing mycoplasma species is discussed. Images PMID:2370103

  18. 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.

  19. 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.

  20. 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

  1. The double sheath system and tendon gliding in zone 2C.

    PubMed

    Tang, J B

    1995-06-01

    Anatomical structures, the morphology of gliding tunnel, the gliding amplitude of tendons and the range of finger motion after sheath incision in zone 2C were studied in 40 fingers of ten preserved cadaver hands. The tendon of FDS in zone 2C courses around that of FDP, and FDS serves functionally as a second sheath for FDP. This "double sheath" system in zone 2C accounts for the poor results of tendon repair in zone 2C. The tendon repairs in zone 2C glide into zone 2D during finger flexion. Therefore, the condition of the gliding tunnel of zone 2D is also important to the function of tendon repairs in zone 2C. The range of motion was shown to be insignificantly influenced by partial incision of the A2 pulley, and this did not decrease the total strength of the sheath markedly. These suggest that partial incision or enlargement of the A2 pulley can be carried out for tendon repairs in zone 2C without causing mechanical problems of function.

  2. The Hydrodynamic Study of the Swimming Gliding: a Two-Dimensional Computational Fluid Dynamics (CFD) Analysis.

    PubMed

    Marinho, Daniel A; Barbosa, Tiago M; Rouboa, Abel I; Silva, António J

    2011-09-01

    Nowadays the underwater gliding after the starts and the turns plays a major role in the overall swimming performance. Hence, minimizing hydrodynamic drag during the underwater phases should be a main aim during swimming. Indeed, there are several postures that swimmers can assume during the underwater gliding, although experimental results were not conclusive concerning the best body position to accomplish this aim. Therefore, the purpose of this study was to analyse the effect in hydrodynamic drag forces of using different body positions during gliding through computational fluid dynamics (CFD) methodology. For this purpose, two-dimensional models of the human body in steady flow conditions were studied. Two-dimensional virtual models had been created: (i) a prone position with the arms extended at the front of the body; (ii) a prone position with the arms placed alongside the trunk; (iii) a lateral position with the arms extended at the front and; (iv) a dorsal position with the arms extended at the front. The drag forces were computed between speeds of 1.6 m/s and 2 m/s in a two-dimensional Fluent(®) analysis. The positions with the arms extended at the front presented lower drag values than the position with the arms aside the trunk. The lateral position was the one in which the drag was lower and seems to be the one that should be adopted during the gliding after starts and turns.

  3. Evolutionarily divergent, unstable filamentous actin is essential for gliding motility in apicomplexan parasites.

    PubMed

    Skillman, Kristen M; Diraviyam, Karthikeyan; Khan, Asis; Tang, Keliang; Sept, David; Sibley, L David

    2011-10-01

    Apicomplexan parasites rely on a novel form of actin-based motility called gliding, which depends on parasite actin polymerization, to migrate through their hosts and invade cells. However, parasite actins are divergent both in sequence and function and only form short, unstable filaments in contrast to the stability of conventional actin filaments. The molecular basis for parasite actin filament instability and its relationship to gliding motility remain unresolved. We demonstrate that recombinant Toxoplasma (TgACTI) and Plasmodium (PfACTI and PfACTII) actins polymerized into very short filaments in vitro but were induced to form long, stable filaments by addition of equimolar levels of phalloidin. Parasite actins contain a conserved phalloidin-binding site as determined by molecular modeling and computational docking, yet vary in several residues that are predicted to impact filament stability. In particular, two residues were identified that form intermolecular contacts between different protomers in conventional actin filaments and these residues showed non-conservative differences in apicomplexan parasites. Substitution of divergent residues found in TgACTI with those from mammalian actin resulted in formation of longer, more stable filaments in vitro. Expression of these stabilized actins in T. gondii increased sensitivity to the actin-stabilizing compound jasplakinolide and disrupted normal gliding motility in the absence of treatment. These results identify the molecular basis for short, dynamic filaments in apicomplexan parasites and demonstrate that inherent instability of parasite actin filaments is a critical adaptation for gliding motility.

  4. Evolutionarily Divergent, Unstable Filamentous Actin Is Essential for Gliding Motility in Apicomplexan Parasites

    PubMed Central

    Skillman, Kristen M.; Diraviyam, Karthikeyan; Khan, Asis; Tang, Keliang; Sept, David; Sibley, L. David

    2011-01-01

    Apicomplexan parasites rely on a novel form of actin-based motility called gliding, which depends on parasite actin polymerization, to migrate through their hosts and invade cells. However, parasite actins are divergent both in sequence and function and only form short, unstable filaments in contrast to the stability of conventional actin filaments. The molecular basis for parasite actin filament instability and its relationship to gliding motility remain unresolved. We demonstrate that recombinant Toxoplasma (TgACTI) and Plasmodium (PfACTI and PfACTII) actins polymerized into very short filaments in vitro but were induced to form long, stable filaments by addition of equimolar levels of phalloidin. Parasite actins contain a conserved phalloidin-binding site as determined by molecular modeling and computational docking, yet vary in several residues that are predicted to impact filament stability. In particular, two residues were identified that form intermolecular contacts between different protomers in conventional actin filaments and these residues showed non-conservative differences in apicomplexan parasites. Substitution of divergent residues found in TgACTI with those from mammalian actin resulted in formation of longer, more stable filaments in vitro. Expression of these stabilized actins in T. gondii increased sensitivity to the actin-stabilizing compound jasplakinolide and disrupted normal gliding motility in the absence of treatment. These results identify the molecular basis for short, dynamic filaments in apicomplexan parasites and demonstrate that inherent instability of parasite actin filaments is a critical adaptation for gliding motility. PMID:21998582

  5. The effects of real and illusory glides on pure-tone frequency discrimination

    NASA Astrophysics Data System (ADS)

    Lyzenga, J.; Carlyon, R. P.; Moore, B. C. J.

    2004-07-01

    Experiment 1 measured pure-tone frequency difference limens (DLs) at 1 and 4 kHz. The stimuli had two steady-state portions, which differed in frequency for the target. These portions were separated by a middle section of varying length, which consisted of a silent gap, a frequency glide, or a noise burst (conditions: gap, glide, and noise, respectively). The noise burst created an illusion of the tone continuing through the gap. In the first condition, the stimuli had an overall duration of 500 ms. In the second condition, stimuli had a fixed 50-ms middle section, and the overall duration was varied. DLs were lower for the glide than for the gap condition, consistent with the idea that the auditory system contains a mechanism specific for the detection of dynamic changes. DLs were generally lower for the noise than for the gap condition, suggesting that this mechanism extracts information from an illusory glide. In a second experiment, pure-tone frequency direction-discrimination thresholds were measured using similar stimuli as for the first experiment. For this task, the type of the middle section hardly affected the thresholds, suggesting that the frequency-change detection mechanism does not facilitate the identification of the direction of frequency changes.

  6. 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...

  7. The effect of lubricin on the gliding resistance of mouse intrasynovial tendon.

    PubMed

    Hayashi, Masanori; Zhao, Chunfeng; Thoreson, Andrew R; Chikenji, Takako; Jay, Gregory D; An, Kai-Nan; Amadio, Peter C

    2013-01-01

    The purpose of this study was to investigate the role of lubricin on the gliding resistance of intrasynovial tendons by comparing lubricin knockout, heterozygous, and wild type mice. A total of thirty-six deep digital flexor (DDF) tendons in the third digits of each hind paw from eighteen adult mice were used, including six lubricin knockout mice (Prg4 -/-), six heterozygous mice (Prg4 +/-), and six wild type mice (Prg4 +/+). The tendon gliding resistance was measured using a custom-made device. Tendon structural changes were evaluated by scanning electron and light microscopy. The gliding resistance of intrasynovial tendons from lubricin knockout mice was significantly higher than the gliding resistance of either wild type or heterozygous mice. The surface of the lubricin knockout tendons appeared to be rougher, compared to the wild type and heterozygous tendons. Synovial hyperplasia was found in the lubricin knockout mice. Cartilage-like tissue was found in the tendon and pulley of the lubricin knockout mice. Our findings confirm the importance of lubricin in intrasynovial tendon lubrication. This knockout model may be useful in determining the effect of lubricin on tendon healing and the response to injury.

  8. Remote Photoregulated Ring Gliding in a [2]Rotaxane via a Molecular Effector.

    PubMed

    Tron, Arnaud; Pianet, Isabelle; Martinez-Cuezva, Alberto; Tucker, James H R; Pisciottani, Luca; Alajarin, Mateo; Berna, Jose; McClenaghan, Nathan D

    2017-01-06

    A molecular barbiturate messenger, which is reversibly released/captured by a photoswitchable artificial molecular receptor, is shown to act as an effector to control ring gliding on a distant hydrogen-bonding [2]rotaxane. Thus, light-driven chemical communication governing the operation of a remote molecular machine is demonstrated using an information-rich neutral molecule.

  9. 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.

  10. Mycoplasma detection and isolation from one-humped camels (Camelus dromedarius).

    PubMed

    Mederos-Iriarte, Lidia E; Poveda, José B; Poveda, Carlos G; Vega-Orellana, Orestes M; Gutiérrez, Carlos; Corbera, Juan A; Ramírez, Ana S

    2014-10-01

    In scientific literature, a small amount of information is found concerning mycoplasmosis in camel species. Mycoplasma (M.) arginini, Acholeplasma (A.) laidlawii, and Acholeplasma oculi have been reported to be isolated from these host species. Serologically positive results have been reported for Mycoplasma mycoides subsp. mycoides SC type, Mycoplasma capricolum subsp. capripneumoniae, and M. mycoides subsp. capri. The aims of this study were to detect, isolate, and identify mycoplasmas from camels (Camelus dromedarius). Initially, saliva and ear smears plus conjunctival and vaginal secretions were taken from five female animals, but only conjunctival secretions in three male animals, all belonging to the same farm. An unknown mycoplasma was isolated from one of the vagina samples. Additionally, another unknown and uncultured mycoplasma was detected with molecular biology in the same sample. In the second stage, 23 vaginal secretions were taken from the same farm plus another secretion from a different one. Ten isolates of the same unknown and previously isolated mycoplasma were detected, nine of them recovered from the vagina of female camels. Some mycoplasmas have been related to reproductive disorders; however, there is no evidence that the isolated mycoplasmas are related to such disorders.

  11. Comparison of the prevalence of Mycoplasma species in dogs with and without respiratory disease.

    PubMed

    Schulz, Bianka S; Raufeisen, Katharina; Weber, Karin; Laberke, Siija; Hartmann, Katrin

    2015-01-01

    Aim of the study was to investigate the prevalence of Mycoplasma species in dogs with and without signs of respiratory disease. Bronchoalveolarlavage fluid (BALF) and pharyngeal swabs were collected from 29 dogs with respiratory diseases (RD) and 16 dogs without signs of RD that were euthanised because of other diseases. Samples were tested for Mycoplasma species by PCR and culture, and sequencing was performed in Mycoplasma species-positive BALF samples. Pharyngeal swabs were positive for Mycoplasma species by PCR in 91.7% of dogs with RD and 86.7% of dogs without signs of RD (p = 1.000); BALF samples were PCR-positive in 37.9% of dogs with RD and 18.8% of dogs without signs of RD (p = 0.194) Mycoplasmo culture of BALF was positive in 28.6% of dogs with RD and in 18.8% without signs of RD (p = 0.730). When culture and PCR were compared, there was no significant difference in the detection rate of Mycoplasma species (p = 0.658) Sequencing detected different Mycoplasma species. Out of these, however, Mycoplasma cynos was isolated from four dogs with RD. There is no significant difference in the prevalence of Mycoplasma species between dogs with RD and dogs without evidence of RD; however, Mycoplasma cynos seems to be associated with respiratory disease.

  12. In Vitro Antibacterial Activity of AZD0914 against Human Mycoplasmas and Ureaplasmas

    PubMed Central

    Crabb, Donna M.; Duffy, Lynn B.; Huband, Michael D.

    2015-01-01

    In this study, susceptibilities were determined for AZD0914, a spiropyrimidinetrione DNA gyrase inhibitor, azithromycin, doxycycline, and levofloxacin against Mycoplasma and Ureaplasma species. The activity of AZD0914 was comparable to that of levofloxacin and doxycycline against Mycoplasma genitalium and Mycoplasma pneumoniae. The AZD0914 MIC90 against Mycoplasma hominis was 8-fold greater than that for levofloxacin. The AZD0914 MIC90 against Ureaplasma species was 4-fold less than that for azithromycin and 8-fold less than that for levofloxacin and doxycycline. PMID:25824220

  13. 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

  14. Nitrogen Fixation by Gliding Arc Plasma: Better Insight by Chemical Kinetics Modelling.

    PubMed

    Wang, Weizong; Patil, Bhaskar; Heijkers, Stjin; Hessel, Volker; Bogaerts, Annemie

    2017-03-08

    The conversion of atmospheric nitrogen into valuable compounds, that is, so-called nitrogen fixation, is gaining increased interest, owing to the essential role in the nitrogen cycle of the biosphere. Plasma technology, and more specifically gliding arc plasma, has great potential in this area, but little is known about the underlying mechanisms. Therefore, we developed a detailed chemical kinetics model for a pulsed-power gliding-arc reactor operating at atmospheric pressure for nitrogen oxide synthesis. Experiments are performed to validate the model and reasonable agreement is reached between the calculated and measured NO and NO2 yields and the corresponding energy efficiency for NOx formation for different N2 /O2 ratios, indicating that the model can provide a realistic picture of the plasma chemistry. Therefore, we can use the model to investigate the reaction pathways for the formation and loss of NOx . The results indicate that vibrational excitation of N2 in the gliding arc contributes significantly to activating the N2 molecules, and leads to an energy efficient way of NOx production, compared to the thermal process. Based on the underlying chemistry, the model allows us to propose solutions on how to further improve the NOx formation by gliding arc technology. Although the energy efficiency of the gliding-arc-based nitrogen fixation process at the present stage is not comparable to the world-scale Haber-Bosch process, we believe our study helps us to come up with more realistic scenarios of entering a cutting-edge innovation in new business cases for the decentralised production of fertilisers for agriculture, in which low-temperature plasma technology might play an important role.

  15. 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

  16. Detection and antibiotic treatment of Mycoplasma arginini contamination in a mouse epithelial cell line restore normal cell physiology.

    PubMed

    Boslett, Brianna; Nag, Subhra; Resnick, Andrew

    2014-01-01

    Mycoplasma contamination of cultured cell lines is difficult to detect by routine observation. Infected cells can display normal morphology and the slow growth rate of mycoplasma can delay detection for extended periods of time, compromising experimental results. Positive identification of mycoplasma typically requires cells to be either fixed and stained for DNA or processed with PCR. We present a method to detect mycoplasma using live-cell optical microscopy typically used for routine observation of cell cultures. Images of untreated mycoplasma-infected epithelial cells alongside images of infected cells treated with Plasmocin, a commercially available antibiotic targeted to mycoplasma, are shown. We found that optical imaging is an effective screening tool for detection of mycoplasma contamination. Importantly, we found that cells regained normal function after the contamination was cleared. In conclusion, we present a technique to diagnose probable mycoplasma infections in live cultures without fixation, resulting in faster response times and decreased loss of cell material.

  17. 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.

  18. 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.

  19. Experimental study of gliding arc plasma channel motion: buoyancy and gas flow phenomena under normal and hypergravity conditions

    NASA Astrophysics Data System (ADS)

    Potočňáková, Lucia; Šperka, Jiří; Zikán, Petr; van Loon, Jack J. W. A.; Beckers, Job; Kudrle, Vít

    2017-04-01

    The details of plasma channel motion are investigated by frame-by-frame image analysis of high speed recording of a gliding arc. The gliding arc is operated in several noble gases at various flow rates, voltages and artificial gravity levels. Several peculiarities in evolution of individual glides are observed, described and discussed, such as accelerating motion of plasma channel or shortcutting events of various kinds. Statistics of averaged parameters are significantly different for buoyancy and gas drag dominated regimes, which is put into relation with differing flow patterns for hypergravity and high gas flow.

  20. Submerged swimming of the great cormorant Phalacrocorax carbo sinensis is a variant of the burst-and-glide gait.

    PubMed

    Ribak, Gal; Weihs, Daniel; Arad, Zeev

    2005-10-01

    Cormorants are water birds that forage by submerged swimming in search and pursuit of fish. Underwater they swim by paddling with both feet simultaneously in a gait that includes long glides between consecutive strokes. At shallow swimming depths the birds are highly buoyant as a consequence of their aerial lifestyle. To counter this buoyancy cormorants swim underwater with their body at an angle to the swimming direction. This mechanical solution for foraging at shallow depth is expected to increase the cost of swimming by increasing the drag of the birds. We used kinematic analysis of video sequences of cormorants swimming underwater at shallow depth in a controlled research setup to analyze the swimming gait and estimate the resultant drag of the birds during the entire paddling cycle. The gliding drag of the birds was estimated from swimming speed deceleration during the glide stage while the drag during active paddling was estimated using a mathematical ;burst-and-glide' model. The model was originally developed to estimate the energetic saving from combining glides with burst swimming and we used this fact to test whether the paddling gait of cormorants has similar advantages. We found that swimming speed was correlated with paddling frequency (r=0.56, P<0.001, N=95) where the increase in paddling frequency was achieved mainly by shortening the glide stage (r=-0.86, P<0.001, N=95). The drag coefficient of the birds during paddling was higher on average by two- to threefold than during gliding. However, the magnitude of the drag coefficient during the glide was positively correlated with the tilt of the body (r=0.5, P<0.003, N=35) and negatively correlated with swimming speed (r=-0.65, P<0.001, N=35), while the drag coefficient during the stroke was not correlated with tilt of the body (r=-0.11, P>0.5, N=35) and was positively correlated with swimming speed (r=0.41, P<0.015, N=35). Therefore, the difference between the drag coefficient during the glide and

  1. Collaborative study report: evaluation of the ATCC experimental mycoplasma reference strains panel prepared for comparison of NAT-based and conventional mycoplasma detection methods.

    PubMed

    Dabrazhynetskaya, Alena; Volokhov, Dmitriy V; Lin, Tsai-Lien; Beck, Brian; Gupta, Rajesh K; Chizhikov, Vladimir

    2013-11-01

    The main goal of this collaborative study was to evaluate the experimental panel of cryopreserved mycoplasma reference strains recently prepared by the American Type Culture Collection (ATCC(®)) in order to assess the viability and dispersion of cells in the mycoplasma stocks by measuring the ratio between the number of genomic copies (GC) and the number of colony forming units (CFU) in the reference preparations. The employment of microbial reference cultures with low GC/CFU ratios is critical for unbiased and reliable comparison of mycoplasma testing methods based on different methodological approaches, i.e., Nucleic Acid Testing (NAT) and compendial culture-based techniques. The experimental panel included ten different mycoplasma species known to represent potential human and animal pathogens as well as common contaminants of mammalian and avian cell substrates used in research, development, and manufacture of biological products. Fifteen laboratories with expertise in field of mycoplasma titration and quantification of mycoplasmal genomic DNA participated in the study conducted from February to October of 2012. The results of this study demonstrated the feasibility of preparing highly viable and dispersed (possessing low GC/CFU ratios) frozen stocks of mycoplasma reference materials, required for reliable comparison of NAT-based and conventional mycoplasma detection methods.

  2. 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

    ... mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown... publications: (a) Bigland, C. H. and A. J. DaMassa, “A Bio-Assay for Mycoplasma Gallisepticum.” In:...

  3. 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

    ... mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown... publications: (a) Bigland, C. H. and A. J. DaMassa, “A Bio-Assay for Mycoplasma Gallisepticum.” In:...

  4. 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

    ... mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown... publications: (a) Bigland, C. H. and A. J. DaMassa, “A Bio-Assay for Mycoplasma Gallisepticum.” In:...

  5. Studies into the prevalence of Mycoplasma species in small ruminants in Benue State, North-central Nigeria.

    PubMed

    Akwuobu, Chinedu A; Ayling, Roger D; Chah, Kennedy Foinkfu; Oboegbulem, Stephen I

    2014-08-01

    The indicative prevalence of respiratory Mycoplasma species in small ruminants (SR) was determined in North-central Nigeria. Nasal swabs from 172 sheep and 336 goats from the Northeast, Northwest and South Senatorial Districts of Benue State were examined. Initial Mycoplasma isolation used Mycoplasma culture techniques followed by digitonin sensitivity testing. Species identification was done using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE). Overall, Mycoplasma organisms were isolated from 131 (25.8 %) of the 508 SR examined. Prevalence rates of 18.1 and 29.8 % were recorded for sheep and goats, respectively. A total of 135 isolates of Mycoplasma belonging to three different species were identified: Mycoplasma ovipneumoniae (127), Mycoplasma arginini (7) and Mycoplasma mycoides subspecies capri (1). More than one Mycoplasma species were detected in four (3.1 %) of the 131 confirmed Mycoplasma positive cultures. Mycoplasma was isolated from 16.2 and 29.1 % of animals with and without respiratory signs, respectively. The high isolation rate of mycoplasmas in apparently healthy and clinically sick sheep and goats in this study indicates a carrier status in these SR which may constitute a serious problem in disease control.

  6. Detection of feline Mycoplasma species in cats with feline asthma and chronic bronchitis.

    PubMed

    Schulz, Bianka S; Richter, Petra; Weber, Karin; Mueller, Ralf S; Wess, Gerhard; Zenker, Isabella; Hartmann, Katrin

    2014-12-01

    Little is known about the aetiology of inflammatory lower airway disease in cats. The aim of this study was to investigate the role of Mycoplasma species in cats with feline asthma (FA) and chronic bronchitis (CB). The study population consisted of 17 cats with FA/CB, and 14 sick cats without clinical and historical signs of respiratory disease, which were euthanased for various other reasons. Nasal swabs, nasal lavage and bronchoalveolar lavage fluid (BALF) samples were taken from patients from both groups. Mycoplasma species culture with modified Hayflick agar and Mycoplasma polymerase chain reaction (PCR) were performed on all samples followed by sequencing of all Mycoplasma species-positive samples for differentiation of subspecies. PCR testing detected significantly more Mycoplasma species-positive BALF samples than Mycoplasma culture (P = 0.021). When cats with oropharyngeal contamination were excluded from comparison, the numbers of Mycoplasma species-positive BALF samples in the group with FA/CB (6/17) and the control group (4/9) were not significantly different (P = 0.6924). While all nasal samples of the cats with FA/CB were negative for Mycoplasma organisms, five samples in the control group (P = 0.041) were positive on PCR. Sequencing revealed Mycoplasma felis in all PCR-positive samples. Mycoplasma species can be detected in the lower airways of cats with FA/CB, as well as in the BALF of sick cats without respiratory signs. Further studies are warranted to investigate the possibility that Mycoplasma species represent commensals of the lower respiratory tract of cats.

  7. Detection of Mycoplasma pneumoniae by using the polymerase chain reaction.

    PubMed Central

    Bernet, C; Garret, M; de Barbeyrac, B; Bebear, C; Bonnet, J

    1989-01-01

    The polymerase chain reaction (PCR) technique was used to detect Mycoplasma pneumoniae. A specific DNA sequence for M. pneumoniae was selected from a genomic library, and two oligonucleotides were chosen in this sequence to give an amplified fragment of 144 base pairs. We show that DNA from different M. pneumoniae strains can be detected by PCR, with DNA from other Mycoplasma species giving negative results. Analysis of biological samples (throat swabs) obtained from hamsters that were experimentally infected with M. pneumoniae showed that PCR was more sensitive and reliable than conventional culture techniques for the detection of M. pneumoniae. Initial experiments on artificially seeded human bronchoalveolar lavages showed that PCR can be used to detect 10(2) to 10(3) organisms. Images PMID:2509513

  8. 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.

  9. Phospholipids and Glycolipids of Sterol-requiring Mycoplasma

    PubMed Central

    Smith, Paul F.; Koostra, Walter L.

    1967-01-01

    The phospholipids of Mycoplasma hominis type 2 strain 07 are composed almost entirely of phosphatidyl glycerol. Traces of other glycerophospholipids may exist. No glycolipids are found. The phospholipids of Mycoplasma sp. avian strain J are composed of diphosphatidyl glycerol, which predominates in older cultures, a monoacyl glycerophosphoryl glycerophosphate, which may serve as a precursor of diphosphatidyl glycerol, and phosphatidyl glycerophosphate. This organism also contains cholesteryl glucoside and an unidentified glycolipid which appears to be similar to a monoglucosyl diglyceride. No turnover or radioisotope labeling of the phospholipids occurs during metabolism. This lack of turnover during growth is indicative of a structural role for these glycerophospholipids. A concomitant decrease of monoacyl glycerophosphoryl glycerophosphate and increase of diphosphatidyl glycerol occurs during growth. PMID:6025304

  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. 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.

  12. Tissue Protecting Antidotes From Anti-Apoptotic Factors of Mycoplasma

    DTIC Science & Technology

    2005-12-12

    release of proinflammatory from human peripheral blood monocytes in a dose-dependent manner. Comparison of the effects of intact lipoproteins with those...comparative genomics of B. cereus and B. anthracis, as well as functional reconstruction of metabolism of numerous sequenced microorganisms. Pavel Komarov...Hoyer, J., Kirchner, H. (1992) Induction of cytokines in human peripheral blood and spleen cells by the Mycoplasma arthritidis-derived superantigen

  13. A serological investigation of Mycoplasma pneumoniae infection on the Witwatersrand.

    PubMed

    Joosting, A C; Harwin, R M; Coppin, A; Battaglia, P; van der Hoef, P

    1976-12-18

    Sera from patients with respiratory disease were examined for antibody to Mycoplasma pneumoniae by complement fixation test. During the study period of about 6 years, a 3-year cycle of infection was observed, which coincided with some epidemics in the UK and USA, suggesting the possibility of an approximately simultaneous world-wide spread. The epidemics lasted about 18 months each, during which the incidence of infection was over 10 times that of the interepidemic periods.

  14. 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

  15. Rhamnose Links Moonlighting Proteins to Membrane Phospholipid in Mycoplasmas

    PubMed Central

    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

  16. Mycoplasma and associated bacteria isolated from ovine pink-eye.

    PubMed

    Langford, E V

    1971-01-01

    A mycoplasma was recovered from the untreated conjunctival membranes of nine sheep affected by Pink-eye. It was neither isolated from the conjunctiva of treated animals which were affected nor from the conjunctiva of normal animals either in contact or not in contact with affected animals. Bacteria found on normal conjunctival membranes were Neisseria ovis, Escherichia coli, Staphylococcus epidermididis, Streptococcus and Bacillus spp. Bacteria found in clinical cases of Pink-eye were N. ovis, E. coli, a Streptococcus and Pseudomonas spp.

  17. 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.

  18. Comparative Analysis of Gene Content Evolution in Phytoplasmas and Mycoplasmas

    PubMed Central

    Lin, Chan-Pin; Kuo, Chih-Horng

    2012-01-01

    Phytoplasmas and mycoplasmas are two groups of important pathogens in the bacterial class Mollicutes. Because of their economical and clinical importance, these obligate pathogens have attracted much research attention. However, difficulties involved in the empirical study of these bacteria, particularly the fact that phytoplasmas have not yet been successfully cultivated outside of their hosts despite decades of attempts, have greatly hampered research progress. With the rapid advancements in genome sequencing, comparative genome analysis provides a new approach to facilitate our understanding of these bacteria. In this study, our main focus is to investigate the evolution of gene content in phytoplasmas, mycoplasmas, and their common ancestor. By using a phylogenetic framework for comparative analysis of 12 complete genome sequences, we characterized the putative gains and losses of genes in these obligate parasites. Our results demonstrated that the degradation of metabolic capacities in these bacteria has occurred predominantly in the common ancestor of Mollicutes, prior to the evolutionary split of phytoplasmas and mycoplasmas. Furthermore, we identified a list of genes that are acquired by the common ancestor of phytoplasmas and are conserved across all strains with complete genome sequences available. These genes include several putative effectors for the interactions with hosts and may be good candidates for future functional characterization. PMID:22479625

  19. 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

  20. Transcriptional Profiling of Mycoplasma hyopneumoniae during Heat Shock Using Microarrays†

    PubMed Central

    Madsen, Melissa L.; Nettleton, Dan; Thacker, Eileen L.; Edwards, Robert; Minion, F. Chris

    2006-01-01

    Bacterial pathogens undergo stress during host colonization and disease processes. These stresses result in changes in gene expression to compensate for potentially lethal environments developed in the host during disease. Mycoplasma hyopneumoniae colonizes the swine epithelium and causes a pneumonia that predisposes the host to enhanced disease from other pathogens. How M. hyopneumoniae responds to changing environments in the respiratory tract during disease progression is not known. In fact, little is known concerning the capabilities of mycoplasmas to respond to changing growth environments. With limited genes, mycoplasmas are thought to possess only a few mechanisms for gene regulation. A microarray consisting of 632 of the 698 open reading frames of M. hyopneumoniae was constructed and used to study gene expression differences during a temperature shift from 37°C to 42°C, a temperature swing that might be encountered during disease. To enhance sensitivity, a unique hexamer primer set was employed for generating cDNA from only mRNA species. Our analysis identified 91 genes that had significant transcriptional differences in response to heat shock conditions (P < 0.01) with an estimated false-discovery rate of 4 percent. Thirty-three genes had a change threshold of 1.5-fold or greater. Many of the heat shock proteins previously characterized in other bacteria were identified as significant in this study as well. A proportion of the identified genes (54 of 91) currently have no assigned function. PMID:16368969

  1. Serological Screening Suggests Extensive Presence of Mycoplasma gallisepticum and Mycoplasma synoviae in Backyard Chickens in Southern Mozambique

    PubMed Central

    Taunde, Paula; Zandamela, Ana Felicidade; Junior, Alberto Pondja; Chilundo, Abel; Costa, Rosa

    2017-01-01

    A total of 459 serum samples from unvaccinated backyard chickens originating from 4 villages in Mandlakazi district, Southern Mozambique, were tested for the presence of Mycoplasma gallisepticum and Mycoplasma synoviae antibodies through commercial enzyme-linked immunoabsorbent assay [ELISA] kits. Anti-MG and anti-MS antibodies were detected in all villages surveyed and the overall seroprevalence was 48.8% [95% CI 39.1–57.8] and 84.5% [95% CI 76.8–90.4], respectively. The risk of being seropositive for both diseases was higher [P < 0.05] in Chidenguele village than other villages. It is concluded that MG and MS serum antibodies are present in backyard chickens. PMID:28243629

  2. Experimental infection of BHK21 and Vero cell lines with different Mycoplasma spp

    PubMed Central

    Netto, Cristiane; Soccol, Vanete Thomaz; Sepulveda, Lya Madureira; Timenetsky, Jorge

    2014-01-01

    Mycoplasma spp, belongs to the class Mollicutes and is capable to produce alterations in cellular cultures causing damages to the biotechnological industry. Bioproducts generally require two essential inputs, bovine serum and cells. The study herein aims to evaluate the mycoplasma concentrations that affect the growing of BHK21 and Vero cells. The species used were: Mycoplasma orale, M. salivarium, M. arginini and M. hyorhinis, cultivated in a SP4 media. Two contamination tests were performed with BHK21 and Vero cells and one of them applied different concentrations of mycoplasma. In the first one, mycoplasma was applied at the day zero and, in the second one, the contamination was performed after the monolayer establishment. The both cellular cultures presented cytopathic effects with mycoplasma contamination, but the Vero cells suffered more damages than the BHK21 ones. It was also observed that the severity of the cytopathic effect depended on the mycoplasma specie, on the concentration and on the time of contact with the cellular culture, which evidences the importance of controlling the presence of mycoplasma in biotechnological industries. PMID:25763061

  3. Detection, characterization, and molecular typing of human Mycoplasma spp. from major hospitals in Cairo, Egypt.

    PubMed

    Metwally, Mirihan A; Yassin, Aymen S; Essam, Tamer M; Hamouda, Hayam M; Amin, Magdy A

    2014-01-01

    Mycoplasmas are fastidious slow growing organisms lacking a cell wall and mostly isolated from the mucosal surfaces of the respiratory and genitourinary tracts. There is a dearth of information regarding clinical Mycoplasma spp. isolates among Egyptian patients. A total of 170 samples were collected from patients and apparently healthy personnel in local public hospitals in Cairo, Egypt. Isolation of Mycoplasma spp. was carried out using appropriate culture media and further identification was carried out by biochemical tests followed by serotyping using specific antisera. Confirmation was done by PCR for detection of different Mycoplasma spp. using genus-specific primers targeting 16S ribosomal RNA gene. Characterization of the antibiotic resistance and sensitivity pattern against different antimicrobials was carried out using disc diffusion test. The results indicated the presence of six Mycoplasma spp. in 22.94% of the samples. Mycoplasmas were detected more frequently in throat swabs than sputum. Mycoplasma pneumoniae was highly sensitive to macrolides and quinolones but less sensitive to aminoglycosides and tetracyclines. Molecular techniques were found to be of more rapid, highly sensitive, able to detect nonviable organisms, and cost effective. These results shed light on difficulties of Mycoplasma detection and the superiority of molecular techniques over culture.

  4. Experimental infection of BHK21 and Vero cell lines with different Mycoplasma spp.

    PubMed

    Netto, Cristiane; Soccol, Vanete Thomaz; Sepulveda, Lya Madureira; Timenetsky, Jorge

    2014-01-01

    Mycoplasma spp, belongs to the class Mollicutes and is capable to produce alterations in cellular cultures causing damages to the biotechnological industry. Bioproducts generally require two essential inputs, bovine serum and cells. The study herein aims to evaluate the mycoplasma concentrations that affect the growing of BHK21 and Vero cells. The species used were: Mycoplasma orale, M. salivarium, M. arginini and M. hyorhinis, cultivated in a SP4 media. Two contamination tests were performed with BHK21 and Vero cells and one of them applied different concentrations of mycoplasma. In the first one, mycoplasma was applied at the day zero and, in the second one, the contamination was performed after the monolayer establishment. The both cellular cultures presented cytopathic effects with mycoplasma contamination, but the Vero cells suffered more damages than the BHK21 ones. It was also observed that the severity of the cytopathic effect depended on the mycoplasma specie, on the concentration and on the time of contact with the cellular culture, which evidences the importance of controlling the presence of mycoplasma in biotechnological industries.

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

    PubMed

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

    2015-09-01

    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.

  6. Association of Raillietia caprae with the presence of Mycoplasmas in the external ear canal of goats.

    PubMed

    Jimena, Otero Negrete; Laura, Jaramillo Meza; Elena, Miranda Morales Rosa; Alonso, Navarro Hernández Jaime; Teresa, Quintero Martínez María

    2009-11-01

    We did a descriptive study to determine whether the presence in the external ear canal of the Raillietia caprae mites and Mycoplasmas were associated. For that we sampled 360 goats slaughtered at abattoirs in the summer to identify those infested with the mite. We found only 20 infested, so used all of those plus another 47 uninfested goats selected systematically from the population negative for the isolation of Mycoplasmas. These goats came from the regions of Queretaro, Guanajuato, Sinaloa and Estado de México. Sterile swabs were taken from each ear canal of the carcass after removal of the pinna for microscopic observation of the mites and for the isolation of Mycoplasmas in both study groups. The swab samples were inoculated in Friis media for the isolation of Mycoplasmas; then, the isolates were biochemically characterized and identified serologically. We recovered isolates from the earwax of only nine of the 47 control goats, but from the earwax of 11 of the 20 infested goats; another four infested goats had Mycoplasma isolated from the mites but not from the earwax. Mycoplasma cottewii and Mycoplasma yeatsii were the only Mycoplasmas isolated from the uninfested goats, and also were the predominant (29 of 34) isolates from the infested goats and/or from the mites.

  7. Detection, Characterization, and Molecular Typing of Human Mycoplasma spp. from Major Hospitals in Cairo, Egypt

    PubMed Central

    Metwally, Mirihan A.; Yassin, Aymen S.; Essam, Tamer M.; Hamouda, Hayam M.; Amin, Magdy A.

    2014-01-01

    Mycoplasmas are fastidious slow growing organisms lacking a cell wall and mostly isolated from the mucosal surfaces of the respiratory and genitourinary tracts. There is a dearth of information regarding clinical Mycoplasma spp. isolates among Egyptian patients. A total of 170 samples were collected from patients and apparently healthy personnel in local public hospitals in Cairo, Egypt. Isolation of Mycoplasma spp. was carried out using appropriate culture media and further identification was carried out by biochemical tests followed by serotyping using specific antisera. Confirmation was done by PCR for detection of different Mycoplasma spp. using genus-specific primers targeting 16S ribosomal RNA gene. Characterization of the antibiotic resistance and sensitivity pattern against different antimicrobials was carried out using disc diffusion test. The results indicated the presence of six Mycoplasma spp. in 22.94% of the samples. Mycoplasmas were detected more frequently in throat swabs than sputum. Mycoplasma pneumoniae was highly sensitive to macrolides and quinolones but less sensitive to aminoglycosides and tetracyclines. Molecular techniques were found to be of more rapid, highly sensitive, able to detect nonviable organisms, and cost effective. These results shed light on difficulties of Mycoplasma detection and the superiority of molecular techniques over culture. PMID:25506614

  8. Severe anemia associated with Mycoplasma wenyonii infection in a mature cow

    PubMed Central

    Genova, Suzanne G.; Streeter, Robert N.; Velguth, Karen E.; Snider, Timothy A.; Kocan, Katherine M.; Simpson, Katharine M.

    2011-01-01

    The clinical findings, diagnostic tests, and treatment of clinical anemia in a mature Angus cow infected with the hemoplasma Mycoplasma wenyonii are described. Mycoplasma wenyonii has been previously reported to cause clinical anemia in young or splenectomized cattle; however, infection has not been associated with severe anemia in mature animals. PMID:22379205

  9. Seroprevalence of Mycoplasma sp. in farmed bison (Bison bison) herds in western Canada

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycoplasma bovis is emerging as an important pathogen of farmed bison in North America, associated with high morbidity and mortality. An in-house enzyme-linked immunosorbent assay (ELISA) was developed to detect antibodies against Mycoplasma sp. in bison sera. The aims of the study were to estimate ...

  10. Mycoplasma membrane lipoproteins induced proinflammatory cytokines by a mechanism distinct from that of lipopolysaccharide.

    PubMed Central

    Rawadi, G; Roman-Roman, S

    1996-01-01

    To gain a clear understanding of the mechanisms by which mycoplasmas induced the expression of proinflammatory cytokines in monocytic cells, we have studied the induction of interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha, and IL-6 by mycoplasmas in three distinct human myelomonocytic cell lines in comparison with induction by lipopolysaccharide (LPS). HL-60 cell line did not release cytokines when induced with either LPS or mycoplasmas. In contrast to LPS, mycoplasmas failed to increase the weak levels of tumor necrosis factor alpha secreted by phorbol myristate acetate-differentiated U937 cells. In addition, Northern (RNA) blot analysis of cytokine expression in these cells showed that the induction of IL-1 beta by mycoplasmas involves, unlike that by LPS, posttranscriptional events. Interestingly, in THP-1 cells, cytokine induction pathways triggered by mycoplasmas remained operational under conditions where LPS pathways were abolished, suggesting functional independence. The study of cytokine-inducing activity displayed by distinct fractions derived from a series of different mycoplasma species demonstrated that lipid membrane constituents were largely responsible for these effects. Finally, we have demonstrated that tyrosine phosphorylation is a crucial event in the mycoplasma-mediated induction of proinflammatory cytokines in either THP-1 cells or human monocytes. PMID:8550219

  11. 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

  12. Host Cell Responses to Persistent Mycoplasmas - Different Stages in Infection of HeLa Cells with Mycoplasma hominis

    PubMed Central

    Hopfe, Miriam; Deenen, René; Degrandi, Daniel; Köhrer, Karl; Henrich, Birgit

    2013-01-01

    Mycoplasma hominis is a facultative human pathogen primarily associated with bacterial vaginosis and pelvic inflammatory disease, but it is also able to spread to other sites, leading to arthritis or, in neonates, meningitis. With a minimal set of 537 annotated genes, M. hominis is the second smallest self-replicating mycoplasma and thus an ideal model organism for studying the effects of an infectious agent on its host more closely. M. hominis adherence, colonisation and invasion of HeLa cells were characterised in a time-course study using scanning electron microscopy, confocal microscopy and microarray-based analysis of the HeLa cell transcriptome. At 4 h post infection, cytoadherence of M. hominis to the HeLa cell surface was accompanied by differential regulation of 723 host genes (>2 fold change in expression). Genes associated with immune responses and signal transduction pathways were mainly affected and components involved in cell-cycle regulation, growth and death were highly upregulated. At 48 h post infection, when mycoplasma invasion started, 1588 host genes were differentially expressed and expression of genes for lysosome-specific proteins associated with bacterial lysis was detected. In a chronically infected HeLa cell line (2 weeks), the proportion of intracellular mycoplasmas reached a maximum of 10% and M. hominis-filled protrusions of the host cell membrane were seen by confocal microscopy, suggesting exocytotic dissemination. Of the 1972 regulated host genes, components of the ECM-receptor interaction pathway and phagosome-related integrins were markedly increased. The immune response was quite different to that at the beginning of infection, with a prominent induction of IL1B gene expression, affecting pathways of MAPK signalling, and genes connected with cytokine-cytokine interactions and apoptosis. These data show for the first time the complex, time-dependent reaction of the host directed at mycoplasmal clearance and the counter measures of

  13. 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.

  14. Reduced Dislocation Density in GaxIn1-xP Compositionally Graded Buffer Layers through Engineered Glide Plane Switch

    SciTech Connect

    Schulte, Kevin L.; France, Ryan M.; McMahon, William E.; Norman, Andrew G.; Guthrey, Harvey L.; Geisz, John F.

    2016-11-17

    In this work we develop control over dislocation glide dynamics in GaxIn1-xP compositionally graded buffer layers (CGBs) through control of CuPt ordering on the group-III sublattice. The ordered structure is metastable in the bulk, so any glissile dislocation that disrupts the ordered pattern will release stored energy, and experience an increased glide force. Here we show how this connection between atomic ordering and dislocation glide force can be exploited to control the threading dislocation density (TDD) in GaxIn1-xP CGBs. When ordered GaxIn1-xP is graded from the GaAs lattice constant to InP, the order parameter ..eta.. decreases as x decreases, and dislocation glide switches from one set of glide planes to the other. This glide plane switch (GPS) is accompanied by the nucleation of dislocations on the new glide plane, which typically leads to increased TDD. We develop control of the GPS position within a GaxIn1-xP CGB through manipulation of deposition temperature, surfactant concentration, and strain-grading rate. We demonstrate a two-stage GaxIn1-xP CGB from GaAs to InP with sufficiently low TDD for high performance devices, such as the 4-junction inverted metamorphic multi-junction solar cell, achieved through careful control the GPS position. Experimental results are analyzed within the context of a model that considers the force balance on dislocations on the two competing glide planes as a function of the degree of ordering.

  15. Reduced dislocation density in GaxIn1-xP compositionally graded buffer layers through engineered glide plane switch

    NASA Astrophysics Data System (ADS)

    Schulte, K. L.; France, R. M.; McMahon, W. E.; Norman, A. G.; Guthrey, H. L.; Geisz, J. F.

    2017-04-01

    In this work we develop control over dislocation glide dynamics in GaxIn1-xP compositionally graded buffer layers (CGBs) through control of CuPt ordering on the group-III sublattice. The ordered structure is metastable in the bulk, so any glissile dislocation that disrupts the ordered pattern will release stored energy, and experience an increased glide force. Here we show how this connection between atomic ordering and dislocation glide force can be exploited to control the threading dislocation density (TDD) in GaxIn1-xP CGBs. When ordered GaxIn1-xP is graded from the GaAs lattice constant to InP, the order parameter η decreases as x decreases, and dislocation glide switches from one set of glide planes to the other. This glide plane switch (GPS) is accompanied by the nucleation of dislocations on the new glide plane, which typically leads to increased TDD. We develop control of the GPS position within a GaxIn1-xP CGB through manipulation of deposition temperature, surfactant concentration, and strain-grading rate. We demonstrate a two-stage GaxIn1-xP CGB from GaAs to InP with sufficiently low TDD for high performance devices, such as the 4-junction inverted metamorphic multi-junction solar cell, achieved through careful control the GPS position. Experimental results are analyzed within the context of a model that considers the force balance on dislocations on the two competing glide planes as a function of the degree of ordering.

  16. Lesions associated with a novel Mycoplasma sp. in California sea lions (Zalophus californianus) undergoing rehabilitation.

    PubMed

    Haulena, Martin; Gulland, Frances M D; Lawrence, Judith A; Fauquier, Deborah A; Jang, Spencer; Aldridge, Brian; Spraker, Terry; Thomas, Linda C; Brown, Daniel R; Wendland, Lori; Davidson, Maureen K

    2006-01-01

    From July 1999 to November 2001, Mycoplasma sp. was cultured from lesions in 16 California sea lions (Zalophus californianus) undergoing rehabilitation. The Mycoplasma sp. was the likely cause of death of four animals in which it was associated with either pneumonia or polyarthritis. The most common lesion associated with this bacterium was subdermal abscessation, found in 12 animals. Other lesions included intramuscular abscesses, septic arthritis, and lymphadenopathy. Infection was associated with a leukocytosis and left shift in 12 animals. Animals with abscesses improved clinically after surgical lancing, irrigation, and systemic antibiotic therapy. The mycoplasma isolates had a consistent 16S rRNA sequence dissimilar from other Mycoplasma spp. and represent a novel species, Mycoplasma zalophi proposed sp. nov.

  17. Identification and characterization of novel Mycoplasma spp. belonging to the hominis group from griffon vultures.

    PubMed

    Lecis, R; Chessa, B; Cacciotto, C; Addis, M F; Coradduzza, E; Berlinguer, F; Muzzeddu, M; Lierz, M; Carcangiu, L; Pittau, M; Alberti, A

    2010-08-01

    Mycoplasmas are commensals and pathogens of various avian species, and are also regularly found in birds of prey, although their significance to birds' health remains unclear. Here we describe two novel Mycoplasma isolated from the upper respiratory tract of four Eurasian griffon vultures (Gyps fulvus) housed in a wildlife recovery centre in Sardinia (Italy). By sequencing the 16S rRNA gene and the entire 16S/23S intergenic spacer region, the new strains were classified within the Mycoplasma taxonomy at the group and cluster levels, showing that the two isolates fall into the Mycoplasma synoviae and Mycoplasma hominis clusters of the hominis group, respectively. We combined molecular tools and immunoblotting methods in order to further characterize these isolates, and antigenic analyses overall confirmed the molecular findings. Different levels of pathogenicity and prevalence of these strains might have different implications for the conservation and reintroduction of vultures.

  18. Occurrence of mycoplasmas in free-ranging birds of prey in Germany.

    PubMed

    Lierz, M; Hagen, N; Hernadez-Divers, S J; Hafez, H M

    2008-10-01

    Mycoplasmas are well-known avian pathogens of poultry and some passerines. Although reported in birds of prey, their role as pathogens is still unclear. Healthy, free-ranging raptor nestlings sampled during a routine ringing (banding) program, and birds of prey from rehabilitation centers, tested positive for Mycoplasma spp. by culture and a genus-specific polymerase chain reaction (PCR). Given the lack of clinical signs and disease, we suggest that mycoplasmas in raptors may be commensal rather than pathogenic. Using immunobinding assay and species-specific PCR tests, Mycoplasma buteonis, M. falconis, and M. gypis were identified; M. falconis was only detected in falcons. Additionally, some isolates could not be identified. This is the first report of Mycoplasma spp. isolations from Western Marsh Harriers (Circus aeroginosus), a Eurasian Hobby (Falco subbuteo), and a Barn Owl (Tyto alba).

  19. Pulsating-gliding transition in the dynamics of levitating liquid nitorgen droplets.

    SciTech Connect

    Snezhko, A.; Jacob, E. B.; Aranson, I. S.; Materials Science Division; Tel-Aviv Univ.

    2008-04-21

    Hot surfaces can cause levitation of small liquid droplets if the temperature is kept above the Leidenfrost point (220 C for water) due to the pressure formed because of rapid evaporation. Here, we demonstrate a new class of pulsating-gliding dynamic transitions in a special setting of the Leidenfrost effect at room temperatures and above a viscous fluid for droplets of liquid nitrogen. A whole range of highly dynamic patterns unfolds when droplets of liquid nitrogen are poured on the surface of another, more viscous liquid at room temperature. We also discovered that the levitating droplets induce vortex motion in the supporting viscous liquid. Depending on the viscosity of the supporting liquid, the nitrogen droplets either adopt an oscillating (pulsating) star-like shape with different azimuthal symmetries (from 2-9 petals) or glide on the surface with random trajectories. Thus, by varying the viscosity of the supporting liquid, we achieve controlled morphology and dynamics of Leidenfrost droplets.

  20. Mycoplasma species isolated from harbor porpoises (Phocoena phocoena) and a Sowerby's beaked whale (Mesoplodon bidens) stranded in Scottish waters.

    PubMed

    Foster, Geoffrey; McAuliffe, Laura; Dagleish, Mark P; Barley, Jason; Howie, Fiona; Nicholas, Robin A J; Ayling, Roger D

    2011-01-01

    Mycoplasma species were recovered from 10 cetacean carcasses that stranded around Scotland. Mycoplasma phocicerebrale was isolated from the lungs of three harbor porpoises (Phocoena phocoena) as well as from the liver of one of these animals. Novel Mycoplasma spp. were isolated from the lungs of five additional harbor porpoises and the kidney of another. In addition an isolate closely related to Mycoplasma species 13CL was obtained from the kidney of a Sowerby's beaked whale (Mesoplodon bidens). The role of these Mycoplasma species in the disease of cetaceans, their host specificity, diversity, and any relation to cetacean strandings are unknown.

  1. Aerodynamic effects of wing corrugation at gliding flight at low Reynolds numbers

    NASA Astrophysics Data System (ADS)

    Meng, Xue Guang; Sun, Mao

    2013-07-01

    Corrugation gives an insect-wing the advantages of low mass, high stiffness, and low membrane stress. Researchers are interested to know if it is also advantageous aerodynamically. Previous works reported that corrugation enhanced the aerodynamic performance of wings at gliding flight. However, Reynolds numbers considered in these studies were higher than that of gliding insects. The present study showed that in the Reynolds number range of gliding insects, corrugation had negative aerodynamic effects. We studied aerodynamic effects of corrugation at gliding motion using the method of computational fluid dynamics, in the Reynolds number range of Re = 200-2400. Different corrugation patterns were considered. The effect of corrugation on aerodynamic performance was identified by comparing the aerodynamic forces between the corrugated and flat-plate wings, and the underlying flow mechanisms of the corrugation effects were revealed by analyzing the flow fields and surface pressure distributions. The findings are as follows: (1) the effect of corrugation is to decrease the lift, and change the drag only slightly (at 15°-25° angles of attack, lift is decreased by about 16%; at smaller angles of attack, the percentage of lift reduction is even larger because the lift is small). (2) Two mechanisms are responsible for the lift reduction. One is that the pleats at the lower surface of the corrugated wing produce relatively strong vortices, resulting in local low-pressure regions on the lower surface of the wing. The other is that corrugation near the leading edge pushes the leading-edge-separation layer slightly upwards and increases the size of the separation bubble above the upper surface, reducing the "suction pressure," or increasing the pressure, on the upper surface.

  2. Using physical models to study the gliding performance of extinct animals.

    PubMed

    Koehl, M A R; Evangelista, Dennis; Yang, Karen

    2011-12-01

    Aerodynamic studies using physical models of fossil organisms can provide quantitative information about how performance of defined activities, such as gliding, depends on specific morphological features. Such analyses allow us to rule out hypotheses about the function of extinct organisms that are not physically plausible and to determine if and how specific morphological features and postures affect performance. The purpose of this article is to provide a practical guide for the design of dynamically scaled physical models to study the gliding of extinct animals using examples from our research on the theropod dinosaur, †Microraptor gui, which had flight feathers on its hind limbs as well as on its forelimbs. Analysis of the aerodynamics of †M. gui can shed light on the design of gliders with large surfaces posterior to the center of mass and provide functional information to evolutionary biologists trying to unravel the origins of flight in the dinosaurian ancestors and sister groups to birds. Measurements of lift, drag, side force, and moments in pitch, roll, and yaw on models in a wind tunnel can be used to calculate indices of gliding and parachuting performance, aerodynamic static stability, and control effectiveness in maneuvering. These indices permit the aerodynamic performance of bodies of different shape, size, stiffness, texture, and posture to be compared and thus can provide insights about the design of gliders, both biological and man-made. Our measurements of maximum lift-to-drag ratios of 2.5-3.1 for physical models of †M. gui suggest that its gliding performance was similar to that of flying squirrels and that the various leg postures that might have been used by †M. gui make little difference to that aspect of aerodynamic performance. We found that body orientation relative to the movement of air past the animal determines whether it is difficult or easy to maneuver.

  3. 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.

  4. 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.

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

    DOE PAGES

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

    2016-05-03

    The plastic deformation is defined by the proportional to stress elastic deflections of pinned dislocations in climb-enabled glide models of irradiation creep. Here, 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.

  6. 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

    2014-11-07

    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.

  7. 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

    2015-06-08

    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.

  8. The role of mycoplasmas in a conservation project of the lesser kestrel (Falco naumanni).

    PubMed

    Lierz, M; Obon, E; Schink, B; Carbonell, F; Hafez, H M

    2008-12-01

    The lesser kestrel (Falco naumanni) is one of the most endangered bird species in Europe, and a captive breeding and reintroduction project was established. A breeding project is vulnerable to pathogens, e.g., mycoplasmas, reducing the reproductive success and carrying the risk to release pathogens with the birds to the wild. Therefore, 18 infertile eggs and 43 dead in shell embryos of the breeding project, as well as 27 nestlings and 34 adult birds of the captive and three different free-ranging populations were investigated for the occurrence of mycoplasmas by culture and a Mycoplasma genus-specific polymerase chain reaction. All eggs, embryos, and hand-reared nestlings from the captive group were negative. In contrast, all parent-reared nestlings and 88% of the adults were positive. Mycoplasma falconis and unidentifiable mycoplasmas were detected in all groups. Mycoplasma buteonis was found in the captive and only in two of the three free-ranging populations. Sequencing the 16S rRNA gene of six randomly selected unidentified isolates showed that five isolates were similar and most likely had been found previously in a falcon from Germany. The remaining isolate demonstrated a very high homology to unidentified Mycoplasma isolates obtained previously from semen samples of raptors. The results suggest that these isolates might represent two new species. Mycoplasmas seem not to play a major role as pathogens in the breeding project, and there is no evidence that releasing birds poses a risk to the free-ranging population with regard to mycoplasmas. The study seems to be the first to describe the occurrence and role of mycoplasmas in the lesser kestrel.

  9. Gliding characteristics between flexor tendons and surrounding tissues in the carpal tunnel: a biomechanical cadaver study.

    PubMed

    Zhao, Chunfeng; Ettema, Anke M; Osamura, Naoki; Berglund, Lawrence J; An, Kai-Nan; Amadio, Peter C

    2007-02-01

    The purpose of this study was to investigate the gliding characteristics of flexor tendons within the carpal tunnel with varied wrist positions and tendon motion styles, which may help us to understand the relationship between carpal tunnel syndrome (CTS) and repetitive hand motion. Eight fresh human cadaveric wrists and hands were used. The peak (PGR) and mean (MGR) gliding resistance of the middle finger flexor digitorum superficialis tendon were measured with the wrist in 0, 30, and 60 degrees of flexion and extension. While moving all three fingers together, the PGR at 60 degrees flexion was significantly higher than that at 0, 30, or 60 degrees extension. While moving the middle finger alone, the PGR at 60 and 30 degrees flexion was significantly higher than the PGR at 60 degrees extension. The PGR moving the middle finger FDS alone was significantly greater than that for all three digits moving together in 0, 30, and 60 degrees flexion. Differential finger motion with wrist flexion elevated the tendon gliding resistance in the carpal tunnel, which may be relevant in considering the possible role of wrist position and activity in the etiology of CTS.

  10. Omnidirectional autonomous entry guidance based on 3-D analytical glide formulas.

    PubMed

    Yu, Wenbin; Chen, Wanchun; Jiang, Zhiguo; Liu, Xiaoming; Zhou, Hao

    2016-11-01

    An autonomous entry guidance law is developed based on 3-D analytical glide formulas, where the downrange formula is used to plan the longitudinal reference profile in order to meet the downrange and final energy requirements, and the crossrange formula is used to regulate the bank reversals in order to eliminate the crossrange error. As the analytical glide formulas ignore the effects of the Earth׳s rotation, a series of strategies is proposed for compensating these effects, which provides the guidance with the capability of steering the hypersonic glide vehicle with high Lift to Drag ratio (L/D) to any place of the world accurately. The compensation strategies can be summarized into two parts: (1) the reference profiles are properly adjusted by roughly evaluating the effects of the Earth׳s rotation on the aerodynamic profiles over the whole flight, which can compensate most of the effects; (2) the current effects are accurately evaluated and then the guidance commands are slightly modulated for compensating the remaining effects. Due to careful design, the strategies will not result in drastic changes in the Angle of Attack (AOA) and can keep the bank angle almost constant during most of flight.

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

    NASA Astrophysics Data System (ADS)

    Chitoran, Ioana

    2004-05-01

    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.

  12. Measurement of forces applied during Macintosh direct laryngoscopy compared with GlideScope® videolaryngoscopy.

    PubMed

    Russell, T; Khan, S; Elman, J; Katznelson, R; Cooper, R M

    2012-06-01

    Laryngoscopy can induce stress responses that may be harmful in susceptible patients. We directly measured the force applied to the base of the tongue as a surrogate for the stress response. Force measurements were obtained using three FlexiForce Sensors(®) (Tekscan Inc, Boston, MA, USA) attached along the concave surface of each laryngoscope blade. Twenty-four 24 adult patients of ASA physical status 1-2 were studied. After induction of anaesthesia and neuromuscular blockade, laryngoscopy and tracheal intubation was performed using either a Macintosh or a GlideScope(®) (Verathon, Bothell, WA, USA) laryngoscope. Complete data were available for 23 patients. Compared with the Macintosh, we observed lower median (IQR [range]) peak force (9 (5-13 [3-25]) N vs 20 (14-28 [4-41]) N; p = 0.0001), average force (5 (3-7 [2-19]) N vs 11 (6-16 [1-24]) N; p = 0.0003) and impulse force (98 (42-151 [26-444]) Ns vs 150 (93-207 [17-509]) Ns; p = 0.017) with the GlideScope. Our study shows that the peak lifting force on the base of the tongue during laryngoscopy is less with the GlideScope videolaryngoscope compared with the Macintosh laryngoscope.

  13. 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.

  14. Detection and prevalence of four different hemotropic Mycoplasma spp. in Eastern North Carolina American black bears (Ursus americanus).

    PubMed

    Westmoreland, Lori S H; Stoskopf, Michael K; Maggi, Ricardo G

    2017-02-01

    Hemotropic Mycoplasma spp. are globally emerging, obligate parasitic, epierythrocytic bacteria that infect many vertebrates, including humans. Hemoplasma infection can cause acute life-threatening symptoms or lead to a chronic sub-clinical carrier state. Hemotropic Mycoplasma spp. transmission, prevalence, and host specificity are uncertain. The purpose of this study was to determine the molecular prevalence of Mycoplasma species in blood from 68 free-ranging black bears from the eastern coast of North Carolina. DNA amplification of Mycoplasma 16S rRNA gene identified four distinct species infecting 34/68 (50%) of the black bear blood samples, including Candidatus M. haematoparvum. The high prevalence of hemotropic Mycoplasma infection in this wildlife species highlights the importance of understanding intra and inter species transmission. Black bears may play a role in the transmission of hemotropic Mycoplasma spp. between animals, arthropod vectors, and humans. Further studies are needed to elucidate black bears as a potential reservoir for hemotropic Mycoplasma infections.

  15. Mycoplasma-dependent activation of normal mouse lymphocytes: requirement for functional T lymphocytes in the cytotoxicity reaction mediated by Mycoplasma arthritidis.

    PubMed Central

    Cole, B C; Aldridge, K E; Sullivan, G J; Ward, J R

    1980-01-01

    Syngeneic and allogeneic target cells were killed in the presence of CBA mouse lymphocytes and viable Mycoplasma arthritidis. Medium supplementation had no effect on the response. Nonviable M. arthritidis was also capable of stimulating lymphocytotoxicity, although to a much lesser extent. Cytotoxicity was shown to be largely dependent upon the lymphocytes, since lymphocytes preincubated with mycoplasmas and treated to remove remaining organisms were highly toxic to target cells, whereas supernatants prepared from lymphocyte/mycoplasma mixtures exhibited minimal effects. A 6-h exposure of lymphocytes to mycoplasmas at a ratio of 100:1 was sufficient for commitment to target cell killing. Functional lymphocytes were required for the reaction, since gamma-irradiated lymphocytes did not develop cytotoxic potential despite the fact that the mycoplasmas replicated equally well in the presence of these and untreated lymphocytes. Furthermore, lymphocytes already activated with mycoplasmas lost cytotoxic potential after disruption. The kinetics and degree of lymphocytotoxicity induced by M. arthritidis and phytohemagglutinin toward 51Cr-labeled syngeneic fibroblasts were similar. Removal of most B cells and other adherent cells by column separation did not abrogate the cytotoxic effect. Lymphocyte suspensions treated with anti-Thy 1 antiserum and complement exhibited a marked decrease in their cytotoxic potential when added to labeled target cells in the presence of M. arthritidis. We conclude that the cytotoxic reaction is dependent upon the T-lymphocyte subpopulation. PMID:6969227

  16. 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

  17. The effects of mycoplasma contamination upon the ability to form bioengineered 3D kidney cysts.

    PubMed

    DesRochers, Teresa M; Kuo, Ivana Y; Kimmerling, Erica P; Ehrlich, Barbara E; Kaplan, David L

    2015-01-01

    Mycoplasma contamination of cell cultures is a pervasive, often undiagnosed and ignored problem in many laboratories that can result in reduced cell proliferation and changes in gene expression. Unless contamination is specifically suspected, it is often undetected in two dimensional (2D) cultures and the resulting effects of mycoplasma contamination are rarely appreciated and can lead to incorrect conclusions. Three dimensional (3D) tissue cultures are increasingly utilized to explore tissue development and phenotype. However, 3D cultures are more complex than 2D cell cultures and require a more controlled cellular environment in order to generate structures necessary to mimic in vivo responses and are often maintained for longer time periods. Changes to the microenvironment are assumed to have a more extreme effect upon the success of 3D tissue cultures than 2D cell cultures, but the effects of mycoplasma have not been studied. To test this hypothesis, we grew 2D cell cultures and 3D tissues from pig kidney epithelial cells (LLC-PK1) that were contaminated with mycoplasma and the same stock of cells after mycoplasma removal. We did not observe an effect of mycoplasma contamination on proliferation in 2D monolayer cell culture. However, cyst formation in 3D tissues was altered, with effects upon the number, size and structure of cysts formed. These data serve to reinforce the necessity of testing cell stocks for mycoplasma contamination.

  18. Mycoplasma corogypsi-associated polyarthritis and tenosynovitis in black vultures (Coragyps atratus).

    PubMed

    Van Wettere, A J; Ley, D H; Scott, D E; Buckanoff, H D; Degernes, L A

    2013-03-01

    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.

  19. Extracellular membrane vesicles secreted by mycoplasma Acholeplasma laidlawii PG8 are enriched in virulence proteins.

    PubMed

    Chernov, Vladislav M; Mouzykantov, Alexey A; Baranova, Natalia B; Medvedeva, Elena S; Grygorieva, Tatiana Yu; Trushin, Maxim V; Vishnyakov, Innokentii E; Sabantsev, Anton V; Borchsenius, Sergei N; Chernova, Olga A

    2014-10-14

    Mycoplasmas (class Mollicutes), the smallest prokaryotes capable of self-replication, as well as Archaea, Gram-positive and Gram-negative bacteria constitutively produce extracellular vesicles (EVs). However, little is known regarding the content and functions of mycoplasma vesicles. Here, we present for the first time a proteomics-based characterisation of extracellular membrane vesicles from Acholeplasma laidlawii PG8. The ubiquitous mycoplasma is widespread in nature, found in humans, animals and plants, and is the causative agent of phytomycoplasmoses and the predominant contaminant of cell cultures. Taking a proteomics approach using LC-ESI-MS/MS, we identified 97 proteins. Analysis of the identified proteins indicated that A. laidlawii-derived EVs are enriched in virulence proteins that may play critical roles in mycoplasma-induced pathogenesis. Our data will help to elucidate the functions of mycoplasma-derived EVs and to develop effective methods to control infections and contaminations of cell cultures by mycoplasmas. In the present study, we have documented for the first time the proteins in EVs secreted by mycoplasma vesicular proteins identified in this study are likely involved in the adaptation of bacteria to stressors, survival in microbial communities and pathogen-host interactions. These findings suggest that the secretion of EVs is an evolutionally conserved and universal process that occurs in organisms from the simplest wall-less bacteria to complex organisms and indicate the necessity of developing new approaches to control infects.

  20. 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.

  1. Detection of multiple Mycoplasma species in bulk tank milk samples using real-time PCR and conventional culture and comparison of test sensitivities.

    PubMed

    Justice-Allen, A; Trujillo, J; Goodell, G; Wilson, D

    2011-07-01

    The objective of this study was to further validate a SYBR PCR protocol for Mycoplasma spp. by comparing it with standard microbial culture in the detection of Mycoplasma spp. in bulk tank milk samples. Additionally, we identified Mycoplasma spp. present by analysis of PCR-generated amplicons [dissociation (melt) temperature (T(m)), length, and DNA sequence]. The research presented herein tests the hypothesis that the SYBR PCR protocol is as sensitive as conventional culture for the detection of Mycoplasma spp. in bulk tank milk samples. Mycoplasmas cause several important disease syndromes in cattle, including mastitis in dairy cows. The standard diagnostic method at the herd level has been microbial isolation of mycoplasmas on 1 of several specialized media and speciation through biochemical or immunological techniques; repeated sampling schemes are recommended. The development of a real-time SYBR PCR protocol offers advantages in decrease of time to detection, cost, and complexity. The T(m) of the double-stranded DNA generated from the PCR reaction was used to detect the presence of and tentatively identify the species of mycoplasmas other than Mycoplasma bovis. In the SYBR PCR protocol, the presence of multiple species of mycoplasmas is indicated by an atypical dissociation curve. Gel electrophoresis and sequencing of the amplicons was used to confirm the mycoplasma species present when a non-M. bovis organism was detected (T(m) not equal to M. bovis) and used to identify all the mycoplasma species present for the samples with atypical dissociation curves. Mycoplasma bovis was identified in 83% of SYBR PCR mycoplasma-positive bulk tank samples. Another mycoplasma was identified either alone or in addition to M. bovis in 25% of SYBR PCR mycoplasma-positive bulk tank milk samples. Four species of mycoplasma other than M. bovis (Mycoplasma alkalescens, Mycoplasma arginini, Mycoplasma bovigenitalium, and Mycoplasma gateae) were identified in bulk tank milk samples

  2. 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.

  3. Genital mycoplasmas in women attending the Yaoundé University Teaching Hospital in Cameroon

    PubMed Central

    Njunda, Anna L.; Nsagha, Dickson S.; Assob, Jules C.N.; Palle, John N.; Kamga, Henri L.; Nde, Peter F.; Ntube, Mengang N.C.; Weledji, Patrick E.

    2011-01-01

    Genital mycoplasmas are implicated in pelvic inflammatory diseases, puerperal infection, septic abortions, low birth weight, nongonococcal urethritis and prostatitis as well as spontaneous abortion and infertility in women. There is paucity of data on colonisation of genital mycoplasma in women and their drug sensitivity patterns. The aim of our study was to determine the prevalence of genital mycoplasmas (Ureaplasma urealiticum and Mycoplasma hominis) infection and their drug sensitivity patterns in women. A mycofast kit was used for biochemical determination of mycoplasma infection in 100 randomly selected female patients aged 19–57 years, attending the University of Yaoundé Teaching Hospital (UYTH) from March to June 2010. Informed consent was sought and gained before samples were collected. Genital mycoplasmas were found in 65 patients (65%) [95% CI=55.7–74.3%] and distributed as 41 (41%) [95% CI=31.4–50.6%] for U. urealiticum and 4 (4%) [95% CI=0.20– 7.8%] for M. hominis while there was co-infection in 20 women (20%) [95% CI=12.16–27.84%]. In our study, 57 (57%) [95% CI=47.3–67%] had other organisms, which included C. albicans (19 [19%]), G. vaginalis (35 [35%]) and T. vaginalis (3 [3%]). Among the 65 women with genital mycoplasma, the highest co-infection was with G. vaginalis (33.8%). Pristinamycine was the most effective antibiotic (92%) and sulfamethoxazole the most resistant (8%) antibiotic to genital mycoplasmas. We conclude that genital mycoplasma is a problem in Cameroon and infected women should be treated together with their partners. PMID:28299057

  4. 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.

  5. 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

  6. Occurrence and Relevance of Mycoplasma sturni in Free-Ranging Corvids in Germany.

    PubMed

    Ziegler, Luisa; Möller Palau-Ribes, Franca Möller; Schmidt, Liane; Lierz, Michael

    2017-01-18

    Several Mycoplasma spp. are well-known pathogens in poultry. In birds of prey, White Storks ( Ciconia ciconia ), and some waterfowl (Anatidae, Pelecanidae) species, mycoplasmas occur commonly and seem to be apathogenic or commensal and most likely belong to the physiologic microbial flora of the respiratory tract. In other bird species, such as Common Nightingales ( Luscinia megarhynchos ) and tits (Paridae), Mycoplasma spp. are absent in healthy birds. In corvids, the prevalence and role of Mycoplasma spp. in disease remains unclear. In previous studies, Mycoplasma sturni was detected in diseased corvids; however, those studies included only a limited sample size or preselected individuals. We collected tracheal swabs of 97 free-ranging Corvidae, including 68 randomly selected individuals from hunting bags and 29 birds that had been admitted to a veterinary clinic. Tracheal swabs were examined for Mycoplasma spp. using culture and genus-specific PCR. If Mycoplasma spp. were detected, the species were identified by sequencing the 16S ribosomal (r)RNA gene and 16-23S rRNA intergenic transcribed spacer region. Five of 68 (7%) of the hunted birds and nine of 29 (31%) of the birds admitted to the veterinary clinic were PCR positive. In 13 of 14 PCR-positive samples, mycoplasmas were cultured and M. sturni was the only mycoplasmal species identified. None of the positive corvids from the hunting bags had clinical signs, whereas five of nine birds admitted to the veterinary clinic showed apathy, lameness, injuries, or fractures, which may not be associated with mycoplasmal infections. These data support the notion that M. sturni is the Mycoplasma sp. most frequently found in corvids, though its prevalence and ability to cause disease may involve interaction with other aspects of bird health.

  7. 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.

  8. [In vitro antibiotic sensitivity of French strains of Mycoplasma bovis].

    PubMed

    Poumarat, F; Martel, J L

    1989-01-01

    The in vitro activity of 15 antibiotics was tested with 30-90 Mycoplasma bovis representative strains of bovine lung pathology in France. The distribution of minimal inhibitory concentration (MIC) is homogeneous with low values for spectinomycin, lincomycin, tylosin, gentamicin and baytril, intermediate for chloramphenicol and neomycin, high for nalidixic acid, Flumequine and erythromycin. The MIC distribution is heterogeneous with intermediate values for spiramycin and tetracyclines, and high values for streptomycin. For the later antibiotics, the heterogeneity of the susceptibility suggests a mechanism of acquired resistance.

  9. Anti-Gal-C antibody in autoimmune neuropathies subsequent to mycoplasma infection.

    PubMed

    Kusunoki, S; Chiba, A; Hitoshi, S; Takizawa, H; Kanazawa, I

    1995-04-01

    Four of 82 patients with Guillain-Barré syndrome (GBS) and 1 of 12 with multifocal motor neuropathy (MMN), who previously had had Mycoplasma pneumoniae infections, had serum antibody to galactocerebroside (Gal-C). Two patients with GBS without mycoplasma infection also had anti-Gal-C antibody, whereas none of the normal or the disease controls had it. As Gal-C is a major glycolipid antigen in myelin, anti-Gal-C antibody may function in the pathogenesis of autoimmune demyelinative neuropathies. Mycoplasma pneumoniae appears to be an important preceding infectious agent in autoimmune neuropathies with anti-Gal-C antibody.

  10. Characterisation of mycoplasmas isolated from genital tract infections of sheep in Nigeria.

    PubMed

    Chima, J C; Ojo, M O; Molokwu, J U; Okewole, P A

    1995-09-01

    Four mycoplasma-like organisms isolated from ewes with mucopurulent vaginal discharge and swollen vulva were characterised. Biochemical tests showed three of the isolates to be negative for glucose fermentation and arginine hydrolysis, while the remaining isolate was negative for glucose fermentation but hydrolysed arginine. Serological identification using the growth inhibition, growth precipitation and indirect immunofluorescence tests indicated the three similar isolates as Mycoplasma bovigenitalium and the other isolate as Mycoplasma arginini. There are apparently no previous reports of the isolation of these organisms from the genital tract of sheep in Nigeria.

  11. Short communication: The effect of centrifugation and resuspension on the recovery of Mycoplasma species from milk.

    PubMed

    Punyapornwithaya, V; Fox, L K; Gay, G M; Hancock, D D; Alldredge, J R

    2009-09-01

    Low sensitivity of a single bulk tank milk culture is a major limitation for detection of mycoplasma organisms. We hypothesized that sedimentation of Mycoplasma spp. in a milk sample by centrifugation followed by resuspension in a small volume of fluid before agar plating would increase the ability to detect Mycoplasma spp. compared with direct conventional culture. The experiment was conducted to determine recovery of Mycoplasma spp. from milk as affected by 1) treatment (centrifugation vs. conventional method); 2) 2 species (Mycoplasma bovis and Mycoplasma californicum and 4 strains for each species); and 3) 4 different concentrations of Mycoplasma spp. (1,000, 100, 10, and 1 cfu/mL). A 5-mL portion of mycoplasma suspension from each strain was inoculated into 45 mL of fresh bulk tank milk to achieve concentrations of 1,000, 100, 10, and 1 cfu/mL. Treatment samples were vigorously mixed and centrifuged at 5,000 x g for 30 min. Control samples were vigorously mixed. All samples were plated on modified Hayflick agar. Plates were incubated at 37 degrees C and 5% CO(2) for 5 d. Mean (+/-SE) log(10) mycoplasma counts (cfu/mL) in the treatment groups (1.91 +/- 0.15) were higher than those in the control groups (1.70 +/- 0.16). Recovery of at least 1 mycoplasma colony on agar culture was 100% in both treatment and control groups at high, medium, and low concentrations. At the lowest concentration, recovery of at least 1 mycoplasma colony on agar culture in treatment and control groups was 75% (n = 12/16) and 18.75% (n = 3/16), respectively. Centrifugation of milk followed by suspension in a smaller volume of saline before conventional culture increased the ability to detect mycoplasma microorganisms in the milk sample compared with controls. Recovery by centrifugation appeared best at the lowest concentration where detection of a positive sample was 4 times more likely than when conventional methods were used.

  12. A surface epitope undergoing high-frequency phase variation is shared by Mycoplasma gallisepticum and Mycoplasma bovis.

    PubMed Central

    Yogev, D; Menaker, D; Strutzberg, K; Levisohn, S; Kirchhoff, H; Hinz, K H; Rosengarten, R

    1994-01-01

    We have recently reported that three distinct size- and phase-variable surface lipoproteins (Vsps) of the bovine pathogen Mycoplasma bovis possess a common epitope recognized by monoclonal antibody 1E5. In the present study, we show that this epitope is also present on a size-variant protein (PvpA) of the avian pathogen Mycoplasma gallisepticum. Application of monoclonal antibody 1E5 in Western immunoblot analysis of Triton X-114 phase-fractionated proteins and in colony immunoblots, as well as in trypsin and carboxypeptidase digestion experiments, has demonstrated that (i) PvpA is an integral membrane protein with a free C terminus, (ii) the shared epitope is surface exposed, and (iii) PvpA is subjected to high-frequency phase variation in expression. By using serum antibodies from M. gallisepticum-infected chickens, we were able to demonstrate the immunogenic nature of PvpA and identify three additional highly immunogenic Triton X-114 phase proteins (p67, p72, and p75) also undergoing high-frequency phase variation spontaneously and independently. Metabolic labeling experiments with [14C]palmitate and [14C]oleate revealed that PvpA, in contrast to p67, p72, and p75, is not lipid modified. Southern blot hybridization with restriction fragments carrying the pvpA gene of M. gallisepticum or the vspA gene of M. bovis against digested genomic DNA of the two Mycoplasma species indicated the absence of genetic relatedness between the pvpA and vspA genes. The apparent complexity of the antigenic variation phenomenon in M. gallisepticum is discussed. Images PMID:7523302

  13. Body posture during simulated tracheal intubation: GlideScope(®) videolaryngoscopy vs Macintosh direct laryngoscopy for novices and experts.

    PubMed

    Grundgeiger, T; Roewer, N; Grundgeiger, J; Hurtienne, J; Happel, O

    2015-12-01

    Tracheal intubation requires the anaesthetist to adopt an awkward body posture. To investigate how posture may be improved, we compared the effects of laryngoscopy technique (GlideScope(®) vs Macintosh blade) and experience (novices vs experts) on body posture angles and the Rapid Entire Body Assessment postural analysis score. Novices (25 medical students) and experts (26 anaesthetists) were video-recorded performing intubation in a manikin using both devices. The GlideScope resulted in smaller deflections for all analysed posture angles (all p values < 0.001) except the wrist compared with the Macintosh blade. Novices showed more trunk (p < 0.001) and neck (p = 0.002) flexion than experts. Using the GlideScope resulted in a lower Rapid Entire Body Assessment score compared with using the Macintosh blade (p < 0.001), indicating that the GlideScope resulted in body posture less likely to induce musculoskeletal injuries. From an ergonomic point of view, the GlideScope should be the preferred technique for laryngoscopy.

  14. How Informative are the Vertical Buoyancy and the Prone Gliding Tests to Assess Young Swimmers' Hydrostatic and Hydrodynamic Profiles?

    PubMed

    Barbosa, Tiago M; Costa, Mário J; Morais, Jorge E; Moreira, Marc; Silva, António J; Marinho, Daniel A

    2012-05-01

    The aim of this research was to develop a path-flow analysis model to highlight the relationships between buoyancy and prone gliding tests and some selected anthropometrical and biomechanical variables. Thirty-eight young male swimmers (12.97 ± 1.05 years old) with several competitive levels were evaluated. It were assessed the body mass, height, fat mass, body surface area, vertical buoyancy, prone gliding after wall push-off, stroke length, stroke frequency and velocity after a maximal 25 [m] swim. The confirmatory model included the body mass, height, fat mass, prone gliding test, stroke length, stroke frequency and velocity. All theoretical paths were verified except for the vertical buoyancy test that did not present any relationship with anthropometrical and biomechanical variables nor with the prone gliding test. The good-of-fit from the confirmatory path-flow model, assessed with the standardized root mean square residuals (SRMR), is considered as being close to the cut-off value, but even so not suitable of the theory (SRMR = 0.11). As a conclusion, vertical buoyancy and prone gliding tests are not the best techniques to assess the swimmer's hydrostatic and hydrodynamic profile, respectively.

  15. 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.

  16. Effect of repetitive pecking at working length for glide path preparation using G-file

    PubMed Central

    Ha, Jung-Hong; Jeon, Hyo-Jin; Abed, Rashid El; Chang, Seok-Woo; Kim, Sung-Kyo

    2015-01-01

    Objectives Glide path preparation is recommended to reduce torsional failure of nickel-titanium (NiTi) rotary instruments and to prevent root canal transportation. This study evaluated whether the repetitive insertions of G-files to the working length maintain the apical size as well as provide sufficient lumen as a glide path for subsequent instrumentation. Materials and Methods The G-file system (Micro-Mega) composed of G1 and G2 files for glide path preparation was used with the J-shaped, simulated resin canals. After inserting a G1 file twice, a G2 file was inserted to the working length 1, 4, 7, or 10 times for four each experimental group, respectively (n = 10). Then the canals were cleaned by copious irrigation, and lubricated with a separating gel medium. Canal replicas were made using silicone impression material, and the diameter of the replicas was measured at working length (D0) and 1 mm level (D1) under a scanning electron microscope. Data was analysed by one-way ANOVA and post-hoc tests (p = 0.05). Results The diameter at D0 level did not show any significant difference between the 1, 2, 4, and 10 times of repetitive pecking insertions of G2 files at working length. However, 10 times of pecking motion with G2 file resulted in significantly larger canal diameter at D1 (p < 0.05). Conclusions Under the limitations of this study, the repetitive insertion of a G2 file up to 10 times at working length created an adequate lumen for subsequent apical shaping with other rotary files bigger than International Organization for Standardization (ISO) size 20, without apical transportation at D0 level. PMID:25984473

  17. The Effects of One-Dimensional Glide on the Reaction Kinetics of Interstitial Clusters

    SciTech Connect

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

    2000-12-01

    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 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 (kMC) 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 analytical rate theory. The functional dependence of the sink strength on the sixe and concentration of sinks under mixed 1D/3D migration is shown to lie between that for pure 1D and pure 3D migration and varies with L, the average distance between direction changes of the gliding defects. It is shown that the sink strength in simulations for spherical sinks of radius R under mixed 1D/3D migration for values of L greater than R can be approximated by an expression that varies directly as R2. For small L, the form of the transition from mixed 1D/3D to pure 3D diffusion as L decreases is demonstrated in the simulations, the results of which can be used in the future development of an analytical expression describing this transition region.

  18. Global transcriptional analysis of Mycoplasma hyopneumoniae following exposure to norepinephrine.

    PubMed

    Oneal, Michael J; Schafer, Erin R; Madsen, Melissa L; Minion, F Chris

    2008-09-01

    Mycoplasma hyopneumoniae, a component of the porcine respiratory disease complex, colonizes the respiratory tract of swine by binding to the cilia of the bronchial epithelial cells. Mechanisms of pathogenesis are poorly understood for M. hyopneumoniae, but previous work has indicated that it responds to the environmental stressors heat shock, iron deprivation and oxidative compounds. For successful infection, M. hyopneumoniae must effectively resist host responses to the colonization of the respiratory tract. Among these are changes in hormonal levels in the mucosal secretions. Recent work in the stress responses of other bacteria has included the response to the catecholamine norepinephrine. The idea that M. hyopneumoniae can respond to a host hormone, however, is novel and has not previously been demonstrated. To test this, organisms in the early exponential phase of growth were exposed to 100 muM norepinephrine for 4 h, and RNA samples from these cultures were collected and compared to RNA samples from control cultures using two-colour PCR-based M. hyopneumoniae microarrays. The M. hyopneumoniae response included slowed growth and changes in mRNA transcript levels of 84 genes, 53 of which were upregulated in response to norepinephrine. A larger proportion of the genes upregulated than those downregulated were involved with transcription and translation. The downregulated genes were mostly involved with metabolism, which correlated with the reduction in growth of the mycoplasma. Approximately 51 % of the genes were hypothetical with no known function. Thus, in response to norepinephrine, M. hyopneumoniae appears to upregulate protein expression while downregulating general metabolism.

  19. Experimental arthritis induced by a clinical Mycoplasma fermentans isolate

    PubMed Central

    Rivera, Antonio; Yáñez, Antonio; León-Tello, Gloria; Gil, Constantino; Giono, Silvia; Barba, Eduardo; Cedillo, Lilia

    2002-01-01

    Background Mycoplasma fermentans has been associated with rheumatoid arthritis. Recently, it was detected in the joints and blood of patients with rheumatoid arthritis, but it is not clear yet how the bacteria enter the body and reach the joints. The purpose of this study was to determine the ability of M. fermentans to induce experimental arthritis in rabbits following inoculation of the bacteria in the trachea and knee joints. Methods P-140 and PG-18 strains were each injected in the knee joints of 14 rabbits in order to evaluate and compare their arthritogenicity. P-140 was also injected in the trachea of 14 rabbits in order to test the ability of the bacteria to reach the joints and induce arthritis. Results M. fermentans produced an acute arthritis in rabbits. Joint swelling appeared first in rabbits injected with P-140, which caused a more severe arthritis than PG-18. Both strains were able to migrate to the uninoculated knee joints and they were detected viable in the joints all along the duration of the experiment. Changes in the synovial tissue were more severe by the end of the experiment and characterized by the infiltration of neutrophils and substitution of adipose tissue by connective tissue. Rabbits intracheally injected with P-140 showed induced arthritis and the bacteria could be isolated from lungs, blood, heart, kidney, spleen, brain and joints. Conclusion M. fermentans induced arthritis regardless of the inoculation route. These findings may help explain why mycoplasmas are commonly isolated from the joints of rheumatic patients. PMID:12057023

  20. 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.

  1. Mycoplasma agassizii in Morafka's desert tortoise (Gopherus morafkai) in Mexico.

    PubMed

    Berry, Kristin H; Brown, Mary B; Vaughn, Mercy; Gowan, Timothy A; Hasskamp, Mary Ann; Torres, Ma Cristina Meléndez

    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 Gopherus in 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.

  2. Experimentally induced bovine abortion with Mycoplasma agalactiae subsp bovis.

    PubMed

    Stalheim, O H; Proctor, S J

    1976-08-01

    Two pregnant cows aborted 11 and 18 days after Mycoplasma agalactiae subsp bovis was inoculated into the amniotic fluids. The placentas were retained. The fetuses (approx 100 and 150 days of age) were decomposed; M agalactiae subsp bovis was recovered from several tissues of the fetuses, the placentas, and fetal fluids. The same organism was given by intraperitoneal injection to 2 other pregnant (130 and 180 days, respectively) cows. At necropsy of the latter 36 days later, placentitis was severe; M agalactiae subsp bovis was recovered from the placentas of both cows and from the fetus of 1 cow. Control cows given sterile mycoplasma cultural medium by intraamnion or intraperitoneal injection did not abort and were not infected. When first recovered from the bovine placenta and fetus, M agalactiae subsp bovis grew slowly in liquid medium and assumed bizarre colonial morphology on solidified medium. Colonies were small (0.1 to 0.5 mm) and dark and lacked halos, but they reacted specifically in the direct fluorescent antibody test with equine M agalactiae subsp bovis antiserum. After 1 or 2 subcultures, the isolates grew at a normal rate and displayed their usual colonial morphology.

  3. 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

  4. 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.

  5. Macromolecular Synthesis and Thymineless Death in Mycoplasma laidlawii B1

    PubMed Central

    Smith, Douglas W.; Hanawalt, Philip C.

    1968-01-01

    The relationships between macromolecular synthesis and viability have been studied in the pleuropneumonia-like organism Mycoplasma laidlawii B adapted to a semidefined grwoth medium. This organism exhibited an absolute growth requirement for the nucleosides uridine and thymidine, a partial requirement for guanosine and deoxyguanosine, but no requirement for adenosine, deoxyadenosine, cytosine, and deoxycytosine. Cytosine and deoxycytosine partially satisfied the requirement for uridine. Loss in viability resulted from thymidine deprivation, but not from a deficiency in other growth requirements. This phenomenon of thymineless death in a mycoplasma is similar in many respects to that reported in other bacterial systems. Chloramphenicol specifically inhibited protein synthesis and allowed deoxyribonucleic acid synthesis to proceed to only about 40% of that normally produced per generation period, while causing less inhibition of ribonucleic acid synthesis. Protein synthesis inhibition permitted thymineless death to a survival level of less than 0.5%, but ribonucleic acid synthesis inhibition resulted in a higher (10%) survival level. These results are consistent with previously noted aspects of thymineless death in Escherichia coli strains, which suggest that thymineless death is coupled to ribonucleic acid synthesis. PMID:4881702

  6. 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

  7. Molecular characterization of the uncultivatable hemotropic bacterium Mycoplasma haemofelis.

    PubMed

    Barker, Emily N; Darby, Alistair C; Helps, Chris R; Peters, Iain R; Heesom, Kate J; Arthur, Christopher J; Crossett, Ben; Hughes, Margaret A; Radford, Alan D; Tasker, Séverine

    2011-07-12

    Mycoplasma haemofelis is a pathogenic feline hemoplasma. Despite its importance, little is known about its metabolic pathways or mechanism of pathogenicity due to it being uncultivatable. The recently sequenced M. haemofelis str. Langford 1 genome was analysed and compared to those of other available hemoplasma genomes.Analysis showed that in hemoplasmas genes involved in carbohydrate metabolism are limited to enzymes of the glycolytic pathway, with glucose appearing to be the sole energy source. The majority of the pentose phosphate pathway enzymes that catalyze the de novo synthesis of ribonucleotides were absent, as were cell division protein FtsZ and chaperonins GroEL/ES. Uncharacterized protein paralogs containing putative surface expression motifs, comprised 62% of M. haemofelis and 19% of Mycoplasma suis genome coverage respectively, the majority of which were present in a small number of unstructured islands. Limited mass spectrometry and immunoblot data matched a number of characterized proteins and uncharacterized paralogs, confirming their expression and immunogenicity in vivo.These data have allowed further characterization of these important pathogens, including their limited metabolic capabilities, which may contribute to their uncultivatable status. A number of immunogenic proteins, and a potential mechanism for host immune system evasion, have been identified.

  8. Molecular characterization of the uncultivatable hemotropic bacterium Mycoplasma haemofelis

    PubMed Central

    2011-01-01

    Mycoplasma haemofelis is a pathogenic feline hemoplasma. Despite its importance, little is known about its metabolic pathways or mechanism of pathogenicity due to it being uncultivatable. The recently sequenced M. haemofelis str. Langford 1 genome was analysed and compared to those of other available hemoplasma genomes. Analysis showed that in hemoplasmas genes involved in carbohydrate metabolism are limited to enzymes of the glycolytic pathway, with glucose appearing to be the sole energy source. The majority of the pentose phosphate pathway enzymes that catalyze the de novo synthesis of ribonucleotides were absent, as were cell division protein FtsZ and chaperonins GroEL/ES. Uncharacterized protein paralogs containing putative surface expression motifs, comprised 62% of M. haemofelis and 19% of Mycoplasma suis genome coverage respectively, the majority of which were present in a small number of unstructured islands. Limited mass spectrometry and immunoblot data matched a number of characterized proteins and uncharacterized paralogs, confirming their expression and immunogenicity in vivo. These data have allowed further characterization of these important pathogens, including their limited metabolic capabilities, which may contribute to their uncultivatable status. A number of immunogenic proteins, and a potential mechanism for host immune system evasion, have been identified. PMID:21749699

  9. Plasma treatment of aqueous solutes: Some chemical properties of a gliding arc in humid air

    NASA Astrophysics Data System (ADS)

    Benstaali, B.; Moussa, D.; Addou, A.; Brisset, J.-L.

    1998-11-01

    The chemical properties of the gaseous species generated in a humid air gliding arc discharge are investigated. Aqueous solutions are used as the targets exposed to the plasma, and this allows to evidence strong acid and oxidizing effects on various solutes by means of spectrometric or potentiometric methods. The influence of some working parameters such as the input gas flow, the distance from the electrodes to the target or the electrode gap is examined on the chemical transform and simple experimental laws are derived. A general feature is observed for oxidation and suggests the occurrence of an auto-catalytic step in the relevant kinetic mechanism.

  10. 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.

  11. Surface modification by nonthermal plasma induced by using magnetic-field-assisted gliding arc discharge

    NASA Astrophysics Data System (ADS)

    Feng, Zongbao; Saeki, Noboru; Kuroki, Tomoyuki; Tahara, Mitsuru; Okubo, Masaaki

    2012-07-01

    The authors report on the introduction of a magnetic field to gliding arc discharge (GD) in order to enhance surface modification by nonthermal plasma at atmospheric-pressure. The GD is induced between two wire electrodes by using a pulse high-voltage power supply with peak-to-peak voltage of 5 kV. When a magnetic field of 0.25 T is applied, the GD enlarged and a 19-cm-long stretch of plasma is excited. The surface treatment of polyethylene terephthalate and polytetrafluoroethylene films is performed. The adhesion improved by up to ˜30 times due to the enhanced chemical activity in the films.

  12. Dislocation glide in the presence of either solute atoms or glissile loops.

    SciTech Connect

    Bacon, David J; Osetskiy, Yury N; Rong, Zhouwen; Tapasa, Kanit

    2004-01-01

    Atomic-scale computer simulation is used to investigate obstacle effects on the dynamics of glide of an edge dislocation in two situations. In one, a dislocation in {alpha}-iron encounters copper atoms in solution and it is found that the effect on dislocation velocity under constant stress below the static Peierls stress is strong. In the other, drag of glissile interstitial loops with the same Burgers vector as the dislocation is considered for iron and copper. The drag coefficient of a loop is determined for the first time, and is shown to be related to the diffusivity of clusters of interstitials via a model of dislocation drag of discrete pinning points.

  13. 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.

  14. 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...

  15. Detection of Mycoplasma Contamination Directly from Culture Supernatant Using Polymerase Chain Reaction.

    PubMed

    Pisal, R V; Hrebíková, H; Chvátalová, J; Kunke, D; Filip, S; Mokrý, J

    2016-01-01

    Ensuring mycoplasma-free cell culture is of prime importance as they severely affect cellular characteristics leading to experimental artefacts and spurious results. Various methods persist for mycoplasma detection; out of the whole array of methods polymerase chain reaction (PCR) is the most favoured one because it is highly sensitive, specific and quick. The PCR-based detection procedure involves three steps: cell culture supernatant collection, DNA isolation, and PCR. We have modified this procedure so that cell culture supernatant can directly be used for PCR without the need for DNA extraction. This modification makes the procedure quicker and more sensitive because loss of mycoplasma DNA is prevented and this loss becomes more significant when the level of mycoplasma contamination is very low.

  16. Molecular biology of mycoplasmas: from the minimum cell concept to the artificial cell.

    PubMed

    Cordova, Caio M M; Hoeltgebaum, Daniela L; Machado, Laís D P N; Santos, Larissa Dos

    2016-01-01

    Mycoplasmas are a large group of bacteria, sorted into different genera in the Mollicutes class, whose main characteristic in common, besides the small genome, is the absence of cell wall. They are considered cellular and molecular biology study models. We present an updated review of the molecular biology of these model microorganisms and the development of replicative vectors for the transformation of mycoplasmas. Synthetic biology studies inspired by these pioneering works became possible and won the attention of the mainstream media. For the first time, an artificial genome was synthesized (a minimal genome produced from consensus sequences obtained from mycoplasmas). For the first time, a functional artificial cell has been constructed by introducing a genome completely synthesized within a cell envelope of a mycoplasma obtained by transformation techniques. Therefore, this article offers an updated insight to the state of the art of these peculiar organisms' molecular biology.

  17. Mycoplasma gallisepticum: Influence of cell invasiveness on the outcome of experimental infection in chickens.

    PubMed

    Much, Peter; Winner, Florian; Stipkovits, László; Rosengarten, Renate; Citti, Christine

    2002-11-15

    Recently we have shown that a low (R(low)) and a high laboratory passage (R(high)) of the poultry pathogen Mycoplasma gallisepticum prototype strain R differ markedly in their capability to invade non-phagocytic eukaryotic cells. In the present study the infection traits of these two mycoplasma passages were compared in an in vivo setting. After aerosol inoculation of chickens, M. gallisepticum was re-isolated from the inner organs of birds infected with R(low), whereas no mycoplasma was recovered from the inner organs of birds infected with R(high). These results indicate that the two mycoplasma populations derived from strain R differ in their capacity to cross the mucosal barrier and suggest that cell invasion may play a major role in the observed systemic spreading of M. gallisepticum in its chicken host.

  18. Effect of Mulligan's mobilization with movement technique on gait function in stroke patients.

    PubMed

    Kim, Sang-Lim; Lee, Byoung-Hee

    2016-08-01

    [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.

  19. 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. PMID:27630424

  20. 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.

  1. 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.

  2. Cranial Sixth-Nerve Palsy and Eosinophilia in an Outbreak of Mycoplasma Pneumonia

    PubMed Central

    Wing, Howard J.; Lindzon, Martin

    1987-01-01

    The authors discuss a case in which three siblings presented with Mycoplasma pneumonia. All three had a typical rise in complement fixation antibody titres. However, the sibling with the highest titre also developed cranial sixth-nerve palsy; in addition, she was the only one of the three who did not have an eosinophilia. The authors review the symptomatology of Mycoplasma pneumonia and the involvement of the central nervous system. PMID:21263943

  3. [Case of tuberculous pleurisy distinguished from pleurisy caused by Mycoplasma infection].

    PubMed

    Nakamura, Kazuyoshi; Yamanaka, Tohru; Yoshioka, Yuichi; Horio, Yuko; Iyama, Shinji; Suzumura, Tomoko; Esaki, Toshihiro

    2013-04-01

    We report a case of tuberculous pleurisy that required differentiation from pleurisy caused by Mycoplasma infection. A 28-year-old woman presented to a clinic with fever and pain on the left side of her chest. A chest radiograph revealed pleural effusion in the left thorax, and the condition was diagnosed as bacterial pleurisy. The patient was referred to our hospital because of an increase in the pleural effusion despite antibiotic treatment. Mycoplasma infection was suspected because the patient was young, the white blood cell count was not elevated, and the result of the ImmunoCard Mycoplasma test (IC) for Mycoplasma pneumoniae-specific IgM antibodies was positive. However, the fever persisted even after treatment with azithromycin and pazufloxacin. The left pleural effusion was exudative, with lymphocytosis and high adenosine deaminase (ADA) levels. The results of the QuantiFERON test were positive. Therefore, tuberculous pleurisy was diagnosed, and the effusion subsided after treatment with standard anti-tuberculosis chemotherapy. Although detection of Mycoplasma infection using the IC is rapid and simple, the accuracy of this test is poor. The patient was first diagnosed with pleurisy of Mycoplasma origin because of a single high-particle agglutination titer of 1: 320 and because of the presence of exudative pleural effusion with lymphocytosis and elevated ADA levels, which has been reported in patients with Mycoplasma infection. The results of the IC test and the ADA level of the pleural effusion might not be reliable when distinguishing between tuberculous pleurisy and pleurisy caused by Mycoplasma infection.

  4. MRI appearances of the CNS manifestations of Mycoplasma pneumoniae: a report of two cases.

    PubMed

    Francis, D A; Brown, A; Miller, D H; Wiles, C M; Bennett, E D; Leigh, N

    1988-09-01

    Two patients are reported with Mycoplasma pneumoniae-related cervical myelitis. Magnetic resonance imaging in each case demonstrated clinically silent lesions suggesting more extensive neurological involvement. This supports the concept of widespread immunologically mediated disease occurring as a remote effect of initial M. pneumoniae respiratory infection. Differences from the MRI appearances of a patient with mycoplasma-related Guillian-Barré syndrome imply that more than one antigenic determinant is involved.

  5. Identification of Lipoprotein MslA as a Neoteric Virulence Factor of Mycoplasma gallisepticum▿

    PubMed Central

    Szczepanek, S. M.; Frasca, S.; Schumacher, V. L.; Liao, X.; Padula, M.; Djordjevic, S. P.; Geary, S. J.

    2010-01-01

    Many lipoproteins are expressed on the surfaces of mycoplasmas, and some have been implicated as playing roles in pathogenesis. Family 2 lipoproteins of Mycoplasma pneumoniae have a conserved “mycoplasma lipoprotein X” central domain and a “mycoplasma lipoprotein 10” C-terminal domain and are differentially expressed in response to environmental conditions. Homologues of family 2 lipoproteins are Mycoplasma specific and include the lipoprotein of Mycoplasma gallisepticum, encoded by the MGA0674 gene. Comparative transcriptomic analysis of the M. gallisepticum live attenuated vaccine strain F and the virulent strain Rlow, reported in this study, indicated that MGA0674 is one of several differentially expressed genes. The MGA0674-encoded lipoprotein is a proteolytically processed, immunogenic, TX-114 detergent-phase protein which appears to have antigenic divergence between field strains Rlow and S6. We examined the virulence of an Rlow ΔMGA0674 mutant (P1H9) in vivo and observed reduced recovery and attenuated virulence in the tracheas of experimentally infected chickens. The virulence of two additional Rlow ΔMGA0674 mutants, 2162 and 2204, was assessed in a second in vivo virulence experiment. These mutants exhibited partial to complete attenuation in vivo, but recovery was observed more frequently. Since only Mycoplasma species harbor homologues of MGA0674, the gene product has been renamed “Mycoplasma-specific lipoprotein A” (MslA). Collectively, these data indicate that MslA is an immunogenic lipoprotein exhibiting reduced expression in an attenuated strain and plays a role in M. gallisepticum virulence. PMID:20515935

  6. Use of a mariner-based transposon mutagenesis system to isolate Clostridium perfringens mutants deficient in gliding motility.

    PubMed

    Liu, Hualan; Bouillaut, Laurent; Sonenshein, Abraham L; Melville, Stephen B

    2013-02-01

    Clostridium perfringens is an anaerobic Gram-positive pathogen that causes many human and animal diseases, including food poisoning and gas gangrene. C. perfringens lacks flagella but possesses type IV pili (TFP). We have previously shown that C. perfringens can glide across an agar surface in long filaments composed of individual bacteria attached end to end and that two TFP-associated proteins, PilT and PilC, are needed for this. To discover additional gene products that play a role in gliding, we developed a plasmid-based mariner transposon mutagenesis system that works effectively in C. perfringens. More than 10,000 clones were screened for mutants that lacked the ability to move away from the edge of a colony. Twenty-four mutants (0.24%) were identified that fit the criteria. The genes containing insertions that affected gliding motility fell into nine different categories. One gene, CPE0278, which encodes a homolog of the SagA cell wall-dependent endopeptidase, acquired distinct transposon insertions in two independent mutants. sagA mutants were unable to form filaments due to a complete lack of end-to-end connections essential for gliding motility. Complementation of the sagA mutants with a wild-type copy of the gene restored gliding motility. We constructed an in-frame deletion mutation in the sagA gene and found that this mutant had a phenotype similar to those of the transposon mutants. We hypothesize that the sagA mutant strains are unable to form the molecular complexes which are needed to keep the cells in an end-to-end orientation, leading to separation of daughter cells and the inability to carry out gliding motility.

  7. A rolling-gliding wear simulator for the investigation of tribological material pairings for application in total knee arthroplasty

    PubMed Central

    2010-01-01

    Background Material wear testing is an important technique in the development and evaluation of materials for use in implant for total knee arthroplasty. Since a knee joint induces a complex rolling-gliding movement, standardised material wear testing devices such as Pin-on-Disc or Ring-on-Disc testers are suitable to only a limited extent because they generate pure gliding motion only. Methods A rolling-gliding wear simulator was thus designed, constructed and implemented, which simulates and reproduces the rolling-gliding movement and loading of the knee joint on specimens of simplified geometry. The technical concept was to run a base-plate, representing the tibia plateau, against a pivoted cylindrical counter-body, representing one femur condyle under an axial load. A rolling movement occurs as a result of the friction and pure gliding is induced by limiting the rotation of the cylindrical counter-body. The set up also enables simplified specimens handling and removal for gravimetrical wear measurements. Long-term wear tests and gravimetrical wear measurements were carried out on the well known material pairings: cobalt chrome-polyethylene, ceramic-polyethylene and ceramic-ceramic, over three million motion cycles to allow material comparisons to be made. Results The observed differences in wear rates between cobalt-chrome on polyethylene and ceramic on polyethylene pairings were similar to the differences of published data for existing material-pairings. Test results on ceramic-ceramic pairings of different frontal-plane geometry and surface roughness displayed low wear rates and no fracture failures. Conclusions The presented set up is able to simulate the rolling-gliding movement of the knee joint, is easy to use, and requires a minimum of user intervention or monitoring. It is suitable for long-term testing, and therefore a useful tool for the investigation of new and promising materials which are of interest for application in knee joint replacement

  8. 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.

  9. [A child with Klippel-Feil syndrome in whom GlideScope was effective for tracheal intubation].

    PubMed

    Arai, Takero; Hashimoto, Yuichi; Saito, Tomoyuki; Ogata, Tokiko; Chiba, Ayako; Sato, Hiromi; Enomoto, Sumie; Shimazaki, Mutsuhisa; Okuda, Yasuhisa

    2013-06-01

    GlideScope videolaryngoscope (GlideScope, herein-after referred to as "GS", Verathon Medical, Bothell, WA, USA), with a high-resolution camera positioned on a blade, enables operators to confirm the position of the larynx and a tube through clear view, thereby conducting intubation safely in a patient whose neck is difficult to be bent back. As the blade is slim, GS is indicated for use in children whose oral cavity is narrow. We herein report safe and smooth intubation with GS in a child with Klippel-Feil syndrome in whom difficult intubation was predicted.

  10. Integrative conjugative elements are widespread in field isolates of Mycoplasma species pathogenic for ruminants.

    PubMed

    Tardy, Florence; Mick, Virginie; Dordet-Frisoni, Emilie; Marenda, Marc Serge; Sirand-Pugnet, Pascal; Blanchard, Alain; Citti, Christine

    2015-03-01

    Comparative genomics have revealed massive horizontal gene transfer (HGT) between Mycoplasma species sharing common ruminant hosts. Further results pointed toward an integrative conjugative element (ICE) as an important contributor of HGT in the small-ruminant-pathogen Mycoplasma agalactiae. To estimate the prevalence of ICEs in ruminant mycoplasmas, we surveyed their occurrence in a collection of 166 field strains representing 4 (sub)species that are recognized as major pathogens. Based on available sequenced genomes, we first defined the conserved, minimal ICE backbone as composed of 4 coding sequences (CDSs) that are evenly distributed and predicted to be essential for ICE chromosomal integration-excision and horizontal transfer. Screening of the strain collection revealed that these 4 CDSs are well represented in ruminant Mycoplasma species, suggesting widespread occurrence of ICEs. Yet their prevalence varies within and among species, with no correlation found with the individual strain history. Extrachromosomal ICE forms were also often detected, suggesting that ICEs are able to circularize in all species, a first and essential step in ICE horizontal transfer. Examination of the junction of the circular forms and comparative sequence analysis of conserved CDSs clearly pointed toward two types of ICE, the hominis and spiroplasma types, most likely differing in their mechanism of excision-integration. Overall, our data indicate the occurrence and maintenance of functional ICEs in a large number of field isolates of ruminant mycoplasmas. These may contribute to genome plasticity and gene exchanges and, presumably, to the emergence of diverse genotypes within pathogenic mycoplasmas of veterinary importance.

  11. Identification of Chlamydiae and Mycoplasma species in ruminants with ocular infections.

    PubMed

    Gupta, S; Chahota, R; Bhardwaj, B; Malik, P; Verma, S; Sharma, M

    2015-02-01

    Infectious keratoconjunctivitis (IKC) is a highly contagious ocular inflammatory condition, which is often reported in domestic small and large ruminants. Multiple infectious aetiologies are reported to be involved, but information about the role of certain fastidious bacterial pathogens such as chlamydiae and mycoplasmas is limited in India. Hence, this study was performed to determine the role of these pathogens and their identification by molecular approach. A total of 53 samples from 31 ovine, 14 caprine and eight bovine having clinical symptoms were collected and tested using species-specific PCR tests for chlamydiae and mycoplasmas followed by nucleotide sequence analysis. The results showed 77.41, 14.29 and 25% samples were chlamydiae positive in ovine, caprine and bovine, respectively, whereas 41.93, 14.29 and 37.5% prevalence of mycoplasma infection was detected in ovine, caprine and bovines, respectively. Chlamydophila abortus, Chlamydophila psittaci, Mycoplasma arginini and Mycoplasma hyorhinis were detected from tested samples. To the best of our knowledge, this is the first time these species are identified in IKC cases from India. Coinfection of both chlamydial and mycoplasmal species was detected in eight IKC cases of ovine which suggest synergistic roles played by both chlamydiae and mycoplasma in IKC samples.

  12. 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.

  13. Adenovirus and mycoplasma infection in an ornate box turtle (Terrapene ornata ornata) in Hungary.

    PubMed

    Farkas, Szilvia L; Gál, János

    2009-07-02

    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.

  14. The detection of "Candidatus Mycoplasma haemobos" in cattle and buffalo in China.

    PubMed

    Su, Q L; Song, H Q; Lin, R Q; Yuan, Z G; Yang, J F; Zhao, G H; Huang, W Y; Zhu, Xing Quan

    2010-12-01

    "Candidatus Mycoplasma haemobos" is a hemoplasma species found in cattle and has been recently reported in Switzerland and Japan. In this study, "Candidatus Mycoplasma haemobos" was shown to occur in cattle and buffalo in tropical China by PCR amplification and sequence analysis of the 16S rRNA gene from blood samples. Based on the 16S rDNA sequence, a specific PCR assay was developed. Occurrence of "Candidatus Mycoplasma haemobos" in cattle and buffalo in Guangxi, China, was determined by examining 25 buffalo blood samples, 12 yellow cattle blood samples and 42 dairy cow blood samples. The results showed that 32% (8/25) of buffalo, 41.7% (5/12) of yellow cattle, and 14.3% (6/42) of dairy cows were positive for "Candidatus Mycoplasma haemobos", respectively. Direct sequencing of representative PCR products confirmed that the amplified partial 16S rDNA sequence represented "Candidatus Mycoplasma haemobos". This is the first report of "Candidatus Mycoplasma haemobos" in buffalo, yellow cattle, and dairy cows in China.

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. 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

    2016-08-09

    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.

  20. 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

    2010-01-05

    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.

  1. 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).

  2. 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.

  3. High quality draft genomes of the Mycoplasma mycoides subsp. mycoides challenge strains Afadé and B237.

    PubMed

    Fischer, Anne; Santana-Cruz, Ivette; Hegerman, Jan; Gourlé, Hadrien; Schieck, Elise; Lambert, Mathieu; Nadendla, Suvarna; Wesonga, Hezron; Miller, Rachel A; Vashee, Sanjay; Weber, Johann; Meens, Jochen; Frey, Joachim; Jores, Joerg

    2015-01-01

    Members of the Mycoplasma mycoides cluster' represent important livestock pathogens worldwide. Mycoplasma mycoides subsp. mycoides is the etiologic agent of contagious bovine pleuropneumonia (CBPP), which is still endemic in many parts of Africa. We report the genome sequences and annotation of two frequently used challenge strains of Mycoplasma mycoides subsp. mycoides, Afadé and B237. The information provided will enable downstream 'omics' applications such as proteomics, transcriptomics and reverse vaccinology approaches. Despite the absence of Mycoplasma pneumoniae like cyto-adhesion encoding genes, the two strains showed the presence of protrusions. This phenotype is likely encoded by another set of genes.

  4. Standardized methods and quality control limits for agar and broth microdilution susceptibility testing of Mycoplasma pneumoniae, Mycoplasma hominis, and Ureaplasma urealyticum.

    PubMed

    Waites, Ken B; Duffy, Lynn B; Bébéar, Cécile M; Matlow, Anne; Talkington, Deborah F; Kenny, George E; Totten, Patricia A; Bade, Donald J; Zheng, Xiaotian; Davidson, Maureen K; Shortridge, Virginia D; Watts, Jeffrey L; Brown, Steven D

    2012-11-01

    An international multilaboratory collaborative study was conducted to develop standard media and consensus methods for the performance and quality control of antimicrobial susceptibility testing of Mycoplasma pneumoniae, Mycoplasma hominis, and Ureaplasma urealyticum using broth microdilution and agar dilution techniques. A reference strain from the American Type Culture Collection was designated for each species, which was to be used for quality control purposes. Repeat testing of replicate samples of each reference strain by participating laboratories utilizing both methods and different lots of media enabled a 3- to 4-dilution MIC range to be established for drugs in several different classes, including tetracyclines, macrolides, ketolides, lincosamides, and fluoroquinolones. This represents the first multilaboratory collaboration to standardize susceptibility testing methods and to designate quality control parameters to ensure accurate and reliable assay results for mycoplasmas and ureaplasmas that infect humans.

  5. Molecular detection of Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' Infection in cats by direct PCR using whole blood without DNA extraction.

    PubMed

    Watanabe, Masashi; Hisasue, Masaharu; Souma, Takehisa; Ohshiro, Shuichi; Yamada, Takatsugu; Tsuchiya, Ryo

    2008-10-01

    Detection of hemotropic Mycoplasma spp. infection was attempted in cats by PCR using whole blood without DNA extraction. A total 46 of 54 (85%) cats with suspected Mycoplasma spp. infection showed a positive reaction, corresponding completely with the results of standard PCR testing. The direct PCR assay was sensitive enough to detect more than 0.0061% parasitemia for ;C. M. haemominutum' and 0.0075% parasitemia for M. haemofelis. These data indicate that the direct PCR assay might be sufficient for use as a tool in clinical examinations.

  6. A serological and molecular study on the occurrence of mycoplasmas in European bison (Bison bonasus) from two areas of Eastern Poland.

    PubMed

    Dudek, K; Bednarek, D; Szacawa, E; Ayling, R D; Krzysiak, M K; Marczuk, J

    2015-01-01

    European bison (Bison bonasus) from two different areas of Eastern Poland showing gross pathology possibly associated with mycoplasma infections were tested for ruminant Mycoplasma species using serological and molecular methods. Fifty-five samples, blood or tissue were collected from 28 animals during 2013-2014. Six sera were positive for Mycoplasma bovis. The ELISA and complement fixation test for Mycoplasma mycoides subsp. mycoides gave a few weak reactions, but were negative by immunoblotting and molecular methods.

  7. 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

  8. Comparative susceptibilities of various animal-pathogenic mycoplasmas to fluoroquinolones.

    PubMed Central

    Hannan, P C; Windsor, G D; de Jong, A; Schmeer, N; Stegemann, M

    1997-01-01

    The in vitro activities of six antimicrobial agents were tested against 162 mycoplasma strains of eight species isolated from poultry and livestock at different geographic sites. Tiamulin was most active (MICs at which 90% of the isolates were inhibited [MIC90s], 0.025 to 0.25 microg/ml); enrofloxacin and danofloxacin had near equivalent activities (MIC90s, 0.05 to 1.0 microg/ml), but were much more active than flumequine (MIC90s, 1 to 50 microg/ml). The MIC90s of tylosin and oxytetracycline were 0.25 to > 100 microg/ml and 0.25 to 100 microg/ml, respectively. PMID:9303412

  9. Molecular distinctions among clinical isolates of Mycoplasma pneumoniae.

    PubMed Central

    Su, C J; Dallo, S F; Baseman, J B

    1990-01-01

    Restriction enzyme fingerprinting of genomic DNA and Southern blots probed with subclones of the Mycoplasma pneumoniae cytadhesin P1 gene were used to characterize clinical isolates of M. pneumoniae. On the basis of the examination of 29 individual M. pneumoniae isolates, two distinct groups were established. Group 1, which displayed a 12-kilobase band following DNA digestion with HindIII, consisted of strain M129-B16 and three others obtained in the state of Washington during the 1960s. The remaining M. pneumoniae strains belonged to group 2, which lacked the 12-kilobase band and included samples from the 1940s, 1970s, and 1980s. This category also included the only M. pneumoniae strain isolated from the synovial fluid of an arthritic patient. Images PMID:2166088

  10. 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.

  11. 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.

  12. Identification of Haemobartonella felis (Mycoplasma haemofelis) in captive nondomestic cats.

    PubMed

    Haefner, Monika; Burke, Thomas J; Kitchell, Barbara E; Lamont, Leigh A; Schaeffer, David J; Behr, Melissa; Messick, Joanne B

    2003-06-01

    This study was undertaken to determine whether Haemobartonella felis (Mycoplasma haemofelis), the causative bacterial agent of feline infectious anemia, infects nondomestic cats. Routine complete blood count and polymerase chain reaction (PCR) were performed to detect the gene for 16S ribosomal RNA for the organism. Sixty-four blood samples were collected from 54 nondomestic cats, including tigers (Panthera tigris), cheetahs (Acinonyx jubatus), lions (P. leo), mountain lions (Felis concolor), snow leopards (P. unica), and a jaguar (P. onca). Some cats were sampled on two or three different dates. Two tigers were positive for H. felis by PCR analysis. As previously described in domestic cats, the parasitemia appears to be intermittent in nondomestic cats.

  13. 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.

  14. 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

  15. Mycoplasma pneumoniae associated opsoclonus-myoclonus syndrome in three cases.

    PubMed

    Huber, Benedikt Maria; Strozzi, Susi; Steinlin, Maja; Aebi, Christoph; Fluri, Simon

    2010-04-01

    Opsoclonus-myoclonus syndrome (OMS) is a rare acquired movement disorder occurring in all age groups, predominantly in infants. Although the exact pathogenesis is still undefined, there is strong evidence for a paraneoplastic or parainfectious immune process resulting in central nervous system dysfunction. Mycoplasma pneumoniae has been implicated in a number of immune-mediated neurologic diseases [28]. However, the association of M. pneumoniae and opsoclonus-myoclonus-ataxia syndrome is not well established so far. We present three cases with opsoclonus-myoclonus-ataxia syndrome in adolescents following an infection with M. pneumoniae. Monophasic disease course and full recovery correspond to the favorable prognosis known from parainfectious cases in young adults. This should affect therapeutic consideration. OMS should be added to the spectrum of M. pneumoniae-associated neurologic complications. Nevertheless, neuroblastoma has to be ruled out in all cases of OMS.

  16. 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

  17. Cortical Blindness in a Child Secondary to Mycoplasma pneumoniae Infection.

    PubMed

    Garcia Tirado, A; Jimenez-Rolando, B; Noval, S; Martinez Bermejo, A

    2017-01-01

    Our objective is to present a case of an uncommon complication associated with Mycoplasma pneumoniae infection in a child where cortical blindness was the main clinical feature. Stroke due to an infection by M. pneumoniae is very uncommon. No consensus has been reached on the pathogenesis, although several pathogenic mechanisms have been proposed. Occlusion of posterior cerebral circulation is the most uncommon central nervous system complication of M. pneumoniae infection being reported. Symptoms are usually hemiplegia and dysarthria. We report a case of a 6-year-old boy who suffered cortical blindness due to a stroke 2 days after M. pneumoniae infection. This is the first case of documented cortical blindness due to posterior cerebral arteries occlusion in children after M. pneumoniae infection.

  18. 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…

  19. Mycoplasma hyopneumoniae colonization of pigs sired by different boars.

    PubMed

    Ruiz, Alvaro; Galina, Lucina; Pijoan, Carlos

    2002-04-01

    Differences in Mycoplasma hyopneumoniae colonization were evaluated in experimentally inoculated pigs sired by 3 different boars of the same genetic line. Forty-six pigs were used, including a treatment group and positive and negative control groups. The pigs were intratracheally inoculated with an M. hyopneumoniae suspension or with Friis media as a placebo. To evaluate differences in the magnitude of colonization during a 35-day period, nasal and tracheal swabs were collected weekly and tested by nested polymerase chain reaction (N-PCR). Temperature, weight and circulating antibodies were measured for 35 days. At 11 and 35 d postinoculation the pigs were necropsied and macroscopic and microscopic lesions were determined. A section of bronchus was tested by the indirect immunofluorescence test (IFAT), scanning electron microscopy (SEM) and N-PCR. The N-PCR results from the nasal and tracheal swabs showed that the pigs sired by one boar (B3) had a distinctive colonization pattern, different from that of the pigs from the other 2 boars and from the positive controls. SEM studies demonstrated that at 35 d postinoculation a higher proportion of B3 pigs had lower numbers of mycoplasmas attached to the cilia compared with B1 and B2 offspring. No significant differences were observed in temperature and weight gain among groups by ANOVA; however, with use of a 2 x 2 table, temperature differences were observed between pigs sired by boars B1 and B2 at 4 d postinoculation. No pigs seroconverted, showed gross or microscopic lesions, or had positive IFAT results. These results provide evidence of differences in patterns of colonization between pigs sired by different boars, suggesting a possible genetic effect.

  20. 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.

  1. The characterization of Mycoplasma synoviae EF-Tu protein and proteins involved in hemadherence and their N-terminal amino acid sequences.

    PubMed

    Bencina, D; Narat, M; Dovc, P; Drobnic-Valic, M; Habe, F; Kleven, S H

    1999-04-01

    An abundant cytoplasmic 43-kDa protein from Mycoplasma synoviae, a major pathogen from poultry, was identified as elongation factor Tu. The N-terminal amino acid sequence (AKLDFDRSKEHVNVGTIGHV) has 90% identity with the sequence of the Mycoplasma hominis elongation factor Tu protein. Monoclonal antibodies reacting with the M. synoviae elongation factor Tu protein also reacted with 43-kDa proteins from the avian Mycoplasma species Mycoplasma gallinarum, Mycoplasma gallinaceum, Mycoplasma pullorum, Mycoplasma cloacale, Mycoplasma iners and Mycoplasma meleagridis, but not with the proteins from Mycoplasma gallisepticum, Mycoplasma imitans or Mycoplasma iowae. In addition, two groups of phase variable integral membrane proteins, pMSA and pMSB, associated with hemadherence and pathogenicity of M. synoviae strains AAY-4 and ULB925 were identified. The cleavage of a larger hemagglutinating protein encoded by a gene homologous to the vlhA gene of M. synoviae generates pMSB1 and pMSA1 proteins defined by mAb 125 and by hemagglutination inhibiting mAb 3E10, respectively. The N-terminal amino acid sequences of pMSA proteins (SENKLI ... and SENETQ ...) probably indicate the cleavage site of the M. synoviae strain ULB 925 hemagglutinin.

  2. 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

  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. 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…

  5. Suture techniques with high breaking strength and low gliding resistance: experiments in the dog flexor digitorum profundus tendon.

    PubMed

    Momose, T; Amadio, P C; Zhao, C; Zobitz, M E; Couvreur, P J; An, K N

    2001-12-01

    We studied the breaking strength and gliding resistance between the pulley and flexor tendon for various suture techniques. Canine flexor digitorum profundus tendons were transected and sutured using one of eight repair techniques: modified Kessler (MK); Tsuge (Tsuge); two variations of a double modified Kessler (DK1, DK2); combined modified Kessler-modified Tsuge (MKT); augmented Becker (Becker); Cruciate (Cruciate); and modified double Tsuge (DT). The force to produce a 1.5 mm gap, ultimate failure load, resistance to gap formation, and gliding resistance were measured. The force to produce a 1.5 mm gap and the ultimate breaking force were higher with the DK1, DK2, MKT, Becker, Cruciate, and DT repairs than they were with the MK and Tsuge repair, while the gliding resistance of the Becker was higher than that of the MK, DK1, DK2, MKT. Cruciate, and UT repairs. In addition to confirming that repair strength increases as the number of strands crossing the repair increases, we also found that these stronger repairs need not produce higher gliding resistance than less robust repairs.

  6. Potential role of Flavobacterial gliding-motility and type IX secretion system complex in root colonization and plant defense.

    PubMed

    Kolton, Max; Frenkel, Omer; Elad, Yigal; Cytryn, Eddie

    2014-09-01

    Members of the Flavobacterium genus are often highly abundant in the rhizosphere. Nevertheless, the physiological characteristics associated with their enhanced rhizosphere competence are currently an enigma. Flavobacteria possess a unique gliding-motility complex that is tightly associated with a recently characterized Bacteroidetes-specific type IX protein secretion system, which distinguishes them from the rest of the rhizosphere microbiome. We hypothesize that proper functionality of this complex may confer a competitive advantage in the rhizosphere. To test this hypothesis, we constructed mutant and complement root-associated flavobacterial variants with dysfunctional secretion and gliding motility, and tested them in a series of in planta experiments. These mutants demonstrated significantly lower rhizosphere persistence (approximately 10-fold), plant root colonization (approximately fivefold), and seed adhesion capacity (approximately sevenfold) than the wild-type strains. Furthermore, the biocontrol capacity of the mutant strain toward foliar-applied Clavibacter michiganensis was significantly impaired relative to the wild-type strain, suggesting a role of the gliding and secretion complex in plant protection. Collectively, these results provide an initial link between the high abundance of flavobacteria in the rhizosphere and their unique physiology, indicating that the flavobacterial gliding-motility and secretion complex may play a central role in root colonization and plant defense.

  7. [Effectiveness of the GlideScope video laryngoscope in a case of unexpected difficult airway due to lingual tonsil hypertrophy].

    PubMed

    Cruz, P; Alarcón, L; Del Castillo, T; Cabrerizo, P; Díaz, S

    2015-05-01

    Lingual tonsil hypertrophy can cause varying degrees of airway obstruction and is considered a risk factor for difficult mask ventilation and tracheal intubation. We report a case of unexpected difficult airway in a patient with unknown lingual tonsil hypertrophy that was solved with the use of the GlideScope video laryngoscope.

  8. 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...

  9. A comparison of the forces applied to a manikin during laryngoscopy with the GlideScope and Macintosh laryngoscopes.

    PubMed

    Russell, T; Lee, C; Firat, M; Cooper, R M

    2011-11-01

    The force applied during laryngoscopy can cause local tissue trauma and can induce cardiovascular responses and cervical spine movement in susceptible patients. Previous studies have identified numerous operator and patient factors that influence the amount of force applied during intubation. There are few studies evaluating the effect of different laryngoscope blades and no study involving video laryngoscopes. In this study we measured the forces using two laryngoscopic techniques. Three FlexiForce Sensors (A201-25, Tekscan, Boston, MA, USA) were attached to the concave blade surface of a Macintosh and a GlideScope laryngoscope. Experienced anaesthetists performed Macintosh and GlideScope intubations on the Laerdal Airway Management Trainer manikin. Compared to Macintosh intubations, the GlideScope intubations had equal or superior views of the glottis with 55%, 58% and 66% lower median peak, average and impulse forces applied to the tongue base. The distal sensor registered the most force in both devices and the force distribution pattern was similar between the devices. The findings suggest that the GlideScope requires less force for similar or better laryngoscopic views, at least in a manikin model.

  10. A cockpit-display concept for executing a multiple glide-slope approach for wake-vortex avoidance

    NASA Technical Reports Server (NTRS)

    Abbott, T. S.

    1984-01-01

    A piloted simulation study was undertaken to determine the feasibility of utilizing a forward-looking display to provide information that would enable aircraft to rredue their in-trail separation interval, and hence increase airport capacity, through the application of multiple glide-path approach techniques. The primary objective of this study was to determine whether information could be satisfactorily provided on a head-up display (HUD) format to permit the pilot to conduct a multiple glide-slope approach while maintaining a prespecified in-trail separation interval. The tests were conducted in a motion-base cockpit simulator configured as a current-generation transport aircraft and included dynamic effects of the vortices generated by the lead aircraft. The information provided on the HUD included typical aircraft guidance information and the current and past positions of the lead aircraft. Additionally, the displayed information provided self-separation cues that allowed the pilot to maintain separation on the lead aircraft. Performance data and pilot subjective ratings and comments were obtained during the tests. The results of this study indicate that multiple glide-slope approaches, procedurally designed for vortex avoidance, are possible while maintaining pilot work load and performance within operationally acceptable limits. In general, it would seem that multiple glide-slope approaches are possible even under reduced in-trail separation conditions if the pilot is provided with adequate situational information.

  11. The application of a non-thermal plasma generated by gas-liquid gliding arc discharge in sterilization

    NASA Astrophysics Data System (ADS)

    Du, Chang Ming; Wang, Jing; Zhang, Lu; Xia Li, Hong; Liu, Hui; Xiong, Ya

    2012-01-01

    Gliding arc discharge has been investigated in recent years as an innovative physicochemical technique for contaminated water treatment at atmospheric pressure and ambient temperature. In this study we tested a gas-liquid gliding arc discharge reactor, the bacterial suspension of which was treated circularly. When the bacterial suspension was passed through the electrodes and circulated at defined flow rates, almost 100% of the bacteria were killed in less than 3.0 min. Experimental results showed that it is possible to achieve an abatement of 7.0 decimal logarithm units within only 30 s. Circulation flow rates and types of feeding gas caused a certain impact on bacteria inactivation, but the influences are not obvious. So, under the promise of sterilization effect, industrial applications can select their appropriate operating conditions. All inactivation curves presented the same three-phase profile showing an apparent sterilization effect. Analysis of the scanning electron microscope images of bacterial cells supports the speculation that the gas-liquid gliding arc discharge plasma is acting under various mechanisms driven essentially by oxidation and the effect of electric field. These results enhance the possibility of applying gas-liquid gliding arc discharge decontamination systems to disinfect bacterial-contaminated water. Furthermore, correlational research indicates the potential applications of this technology in rapid sterilization of medical devices, spacecraft and food.

  12. 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.

  13. 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

  14. Risk of Mycoplasma bovis transmission from contaminated sand bedding to naive dairy calves.

    PubMed

    Wilson, D J; Justice-Allen, A; Goodell, G; Baldwin, T J; Skirpstunas, R T; Cavender, K B

    2011-03-01

    The objective of this study was to evaluate the possible transmission of Mycoplasma bovis from positive sand bedding to naïve dairy calves. Twelve preweaned Holstein bull calves were blocked in pairs and randomly assigned as unexposed controls (n=6) bedded with control sand, or exposed calves (n=6) bedded with sand previously positive for M. bovis at a dairy farm. Bedding sand was cultured weekly. Nasal and ear swabs and sera were collected weekly, tracheal swabs were collected monthly, and by the end of the 105-d study, all calves were euthanized (n=10) or died (n=2). Sera were tested for M. bovis-specific antibody. Mycoplasma spp. culture was performed on nasal and ear swabs; culture and a PCR differentiating multiple Mycoplasma spp. were performed on postmortem samples of lung, retropharyngeal lymph node, and trachea from each calf. A complete necropsy also was performed. During 6 wk, mycoplasma concentration in exposed group sand was between 200 and 32,000 cfu/g. All 166 tracheal swabs, nasal and ear swabs, and postmortem tests from all calves were negative for mycoplasma. All 94 sera were negative for M. bovis-specific antibody. No gross pathology suggestive of mycoplasma disease was detected. The probability of mycoplasma detection, if an exposed calf had become infected 4 wk after exposure, ranged between 97 and 99% depending on time of exposure for individual calves. There was no evidence that sand bedding contaminated with M. bovis might serve as a source of transmission to naïve dairy calves.

  15. Systemic Disease in Vaal Rhebok (Pelea capreolus) Caused by Mycoplasmas in the Mycoides Cluster

    PubMed Central

    Nicolas, Melissa M.; Stalis, Ilse H.; Clippinger, Tracy L.; Busch, Martin; Nordhausen, Robert; Maalouf, Gabriel; Schrenzel, Mark D.

    2005-01-01

    In the winter of 2002, an outbreak of mycoplasma infection in Vaal rhebok (Pelea capreolus) originating from South Africa occurred 15 weeks after their arrival in San Diego, Calif. Three rhebok developed inappetence, weight loss, lethargy, signs related to pulmonary or arthral dysfunction, and sepsis. All three rhebok died or were euthanized. Primary postmortem findings were erosive tracheitis, pleuropneumonia, regional cellulitis, and necrotizing lymphadenitis. Mycoplasmas were detected in numerous tissues by electron microscopy, immunohistochemistry, and PCR. The three deceased rhebok were coinfected with ovine herpesvirus-2, and two animals additionally had a novel gammaherpesvirus. However, no lesions indicative of herpesvirus were seen microscopically in any animal. The rheboks' mycoplasmas were characterized at the level of the 16S rRNA gene, the 16S-23S intergenic spacer region, and the fructose biphosphate aldolase gene. Denaturing gradient gel electrophoresis was carried out to address the possibility of infection with multiple strains. Two of the deceased rhebok were infected with a single strain of Mycoplasma capricolum subsp. capricolum, and the third animal had a single, unique strain most closely related to Mycoplasma mycoides subsp. mycoides large-colony. A PCR survey of DNA samples from 46 other ruminant species demonstrated the presence of several species of mycoplasmas in the mycoides cluster, including a strain of M. capricolum subsp. capricolum identical to that found in two of the rhebok. These findings demonstrate the pervasiveness of mycoplasmas in the mycoides cluster in small ruminants and the potential for interspecies transmission and disease when different animal taxa come in contact. PMID:15750104

  16. 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.

  17. Mycoplasma suis infection results endothelial cell damage and activation: new insight into the cell tropism and pathogenicity of hemotrophic mycoplasma.

    PubMed

    Sokoli, Albina; Groebel, Katrin; Hoelzle, Katharina; Amselgruber, Werner M; Mateos, José M; Schneider, Mårten K J; Ziegler, Urs; Felder, Kathrin M; Hoelzle, Ludwig E

    2013-02-11

    Hemotrophic mycoplasmas (HM) are highly specialized red blood cell parasites that cause infectious anemia in a variety of mammals, including humans. To date, no in vitro cultivation systems for HM have been available, resulting in relatively little information about the pathogenesis of HM infection. In pigs, Mycoplasma suis-induced infectious anemia is associated with hemorrhagic diathesis, and coagulation dysfunction. However, intravasal coagulation and subsequent consumption coagulopathy can only partly explain the sequence of events leading to hemorrhagic diathesis manifesting as cyanosis, petechial bleeding, and ecchymosis, and to disseminated coagulation. The involvement of endothelial activation and damage in M. suis-associated pathogenesis was investigated using light and electron microscopy, immunohistochemistry, and cell sorting. M. suis interacted directly with endothelial cells in vitro and in vivo. Endothelial activation, widespread endothelial damage, and adherence of red blood cells to the endothelium were evident in M. suis-infected pigs. These alterations of the endothelium were accompanied by hemorrhage, intravascular coagulation, vascular occlusion, and massive morphological changes within the parenchyma. M. suis biofilm-like microcolonies formed on the surface of endothelial cells, and may represent a putative persistence mechanism of M. suis. In vitro analysis demonstrated that M. suis interacted with the endothelial cytoskeletal protein actin, and induced actin condensation and activation of endothelial cells, as determined by the up-regulation of ICAM, PECAM, E-selectin, and P-selectin. These findings demonstrate an additional cell tropism of HM for endothelial cells and suggest that M. suis interferes with the protective function of the endothelium, resulting in hemorrhagic diathesis.

  18. Lack of cross-protection against Mycoplasma haemofelis infection and signs of enhancement in "Candidatus Mycoplasma turicensis"-recovered cats.

    PubMed

    Baumann, Julia; Novacco, Marilisa; Willi, Barbara; Riond, Barbara; Meli, Marina L; Boretti, Felicitas S; Hofmann-Lehmann, Regina

    2015-09-24

    "Mycoplasma haemofelis" and "Candidatus Mycoplasma turicensis" are feline hemoplasmas that induce hemolytic anemia. Protection from homologous re-challenge was recently demonstrated in cats recovered from primary infection. Here, we determined if cats recovered from "Cand. M. turicensis" infection were protected against infections with the more pathogenic M. haemofelis. Ten specified pathogen-free cats were exposed to M. haemofelis. Five of the ten cats had recovered from "Cand. M. turicensis" bacteremia (group A), and five cats were naïve controls (group B). No cross-protection was observed. By contrast, the "Cand. M. turicensis"-recovered cats displayed faster M. haemofelis infection onset (earlier PCR-positive and anemic) than the controls. No "Cand. M. turicensis" was detected in any cat. M. haemofelis shedding was observed in saliva, feces and urine. In both groups, evidence of a Th1 response was observed (high IFN-γ, low IL-4), but IL-10 levels were also high. In group A, total, CD4+ and CD8+ T cells increased within days after M. haemofelis exposure. At times of maximal bacteremia, macrocytic hypochromic anemia, neutropenia, monocytosis and a decrease in leukocyte, eosinophil, and lymphocyte counts and subsets thereof (B- and T-cells, CD4+, CD8+ and CD4+CD25+ cells) were particularly significant in group A. Moreover, an increase in protein concentrations, hypoalbuminemia and a polyclonal hypergammaglobulinemia were observed. Five of ten M. haemofelis-infected cats subsequently cleared bacteremia without antibiotic treatment. In conclusion, the study suggests that a previous hemoplasma infection, even when the cat has ostensibly recovered, may influence subsequent infections, lead to an enhancement phenomenon and other differences in infection kinetics.

  19. Development and use of real-time PCR to detect and quantify Mycoplasma haemocanis and "Candidatus Mycoplasma haematoparvum" in dogs.

    PubMed

    Barker, E N; Tasker, S; Day, M J; Warman, S M; Woolley, K; Birtles, R; Georges, K C; Ezeokoli, C D; Newaj-Fyzul, A; Campbell, M D; Sparagano, O A E; Cleaveland, S; Helps, C R

    2010-01-06

    Two canine haemoplasma species have been recognised to date; Mycoplasma haemocanis (Mhc), which has been associated with anaemia in splenectomised or immunocompromised dogs, and "Candidatus Mycoplasma haematoparvum" (CMhp), recently described in an anaemic splenectomised dog undergoing chemotherapy. The study aim was to develop quantitative real-time PCR assays (qPCRs) incorporating an endogenous internal control to detect Mhc and CMhp and to apply these assays to DNA samples extracted from canine blood collected in Northern Tanzania (n=100) and from dogs presented to a Trinidadian veterinary hospital (n=185). QPCRs specific for Mhc and CMhp were designed using 16S rRNA gene sequence data, and each was duplexed with an assay specific for canine glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The assays detected < or =10 copies of a sequence-specific haemoplasma plasmid per reaction and neither assay showed cross-reactivity with 10(6) copies of the sequence-specific plasmid from the non-target canine haemoplasma species. Nineteen of the 100 Tanzanian samples (19%) were positive for Mhc alone and one (1%) was dually infected. One Trinidadian sample was negative for canine GAPDH DNA and was excluded from the study. Of the 184 remaining Trinidadian samples, nine (4.9%) were positive for Mhc alone, five (2.7%) for CMhp alone, and two (1.1%) dually infected. This is the first report of canine haemoplasma qPCR assays that use an internal control to confirm the presence of amplifiable sample DNA, and their application to prevalence studies. Mhc was the most commonly detected canine haemoplasma species.

  20. Glide-plane symmetry and superconducting gap structure of iron-based superconductors

    DOE PAGES

    Wang, Yan; Berlijn, Tom; Hirschfeld, Peter J.; ...

    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. 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.

  2. Numerical Investigation of Swimmer’s Gliding Stage with 6-DOF Movement

    PubMed Central

    Li, Tianzeng; Cai, Wenhao; Zhan, Jiemin

    2017-01-01

    The purpose of this study is to analyze the motion status of swimmers during their gliding stage using a numerical simulation method. This simulation strategy is conducted by solving the 3D incompressible Navier-Stokes equations using the Realizable k-ε turbulence closure equations in combination with the Six Degrees of Freedom (6-DOF) method. The uneven mass distribution of a swimmer and the roughness of the surface of the body are taken into consideration. The hydrodynamic characteristics and movement characteristics of the swimmers at different launch speeds were analyzed. The calculated results suggest that an optimal instant for starting propulsive movement is when the velocity of the swimmer decreases by 1.75 m/s to 2.0 m/s from an initial horizontal velocity of 3.1 m/s to 3.5 m/s. PMID:28125724

  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. 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.

  6. Optimal heading change with minimum energy loss for a hypersonic gliding vehicle

    NASA Astrophysics Data System (ADS)

    Calise, Anthony J.; Bae, Gyoung H.

    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.

  7. 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.

  8. Virtual fragment screening: an exploration of various docking and scoring protocols for fragments using Glide

    NASA Astrophysics Data System (ADS)

    Kawatkar, Sameer; Wang, Hongming; Czerminski, Ryszard; Joseph-McCarthy, Diane

    2009-08-01

    Fragment-based drug discovery approaches allow for a greater coverage of chemical space and generally produce high efficiency ligands. As such, virtual and experimental fragment screening are increasingly being coupled in an effort to identify new leads for specific therapeutic targets. Fragment docking is employed to create target-focussed subset of compounds for testing along side generic fragment libraries. The utility of the program Glide with various scoring schemes for fragment docking is discussed. Fragment docking results for two test cases, prostaglandin D2 synthase and DNA ligase, are presented and compared to experimental screening data. Self-docking, cross-docking, and enrichment studies are performed. For the enrichment runs, experimental data exists indicating that the docking decoys in fact do not inhibit the corresponding enzyme being examined. Results indicate that even for difficult test cases fragment docking can yield enrichments significantly better than random.

  9. 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

  10. Treatment by gliding arc of epoxy resin: preliminary analysis of surface modifications

    NASA Astrophysics Data System (ADS)

    Faubert, F.; Wartel, M.; Pellerin, N.; Pellerin, S.; Cochet, V.; Regnier, E.; Hnatiuc, B.

    2016-12-01

    Treatments with atmospheric pressure non-thermal plasma are easy to implement and inexpensive. Among them gliding arc (GlidArc) remains rarely used in surface treatment of polymers. However, it offers economic and flexible way to treat quickly large areas. In addition the choice of carrier gas makes it possible to bring the active species and other radicals allowing different types of grafting and functionalization of the treated surfaces, for example in order to apply for anti-biofouling prevention. This preliminary work includes analysis of the surface of epoxy resins by infrared spectroscopy: the different affected chemical bonds were studied depending on the duration of treatment. The degree of oxidation (the C/O ratio) is obtained by X-ray microanalysis and contact angle analysis have been performed to determinate the wettability properties of the treated surface. A spectroscopic study of the plasma allows to determine the possible active species in the different zones of the discharge.

  11. 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.

  12. 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.

  13. Lift and Drag Characteristics and Gliding Performance of an Autogiro as Determined in Flight

    NASA Technical Reports Server (NTRS)

    Wheatley, John B

    1933-01-01

    This report presents the results of flight test of the Pitcairn "PCA-2" autogiro. Lift and drag coefficients with the propeller stopped have been determined over approximately a 90 degree range of angles of attack. Based on the sum of fixed-wing and swept-disk areas, the maximum lift coefficient is 0.895, the minimum drag coefficient with propeller stopped is 0.015, and the maximum l/d with propeller stopped is 4.8. Lift coefficients were found also with the propeller delivering positive thrust and did not differ consistently from those found with propeller stopped. Curves of gliding performance included in this report show a minimum vertical velocity of 15 feet per second at an air speed of 36 miles per hour and a flight-path angle of -17 degrees. In vertical descent the vertical velocity is 35 feet per second.

  14. Gliding lizards use the position of the sun to enhance social display.

    PubMed

    Klomp, Danielle A; Stuart-Fox, Devi; Das, Indraneil; Ord, Terry J

    2017-02-01

    Effective communication requires animal signals to be readily detected by receivers in the environments in which they are typically given. Certain light conditions enhance the visibility of colour signals and these conditions can vary depending on the orientation of the sun and the position of the signaller. We tested whether Draco sumatranus gliding lizards modified their position relative to the sun to enhance the conspicuousness of their throat-fan (dewlap) during social display to conspecifics. The dewlap was translucent, and we found that lizards were significantly more likely to orient themselves perpendicular to the sun when displaying. This increases the dewlap's radiance, and likely, its conspicuousness, by increasing the amount of light transmitted through the ornament. This is a rare example of a behavioural adaptation for enhancing the visibility of an ornament to distant receivers.

  15. Wake analysis of drag components in gliding flight of a jackdaw (Corvus monedula) during moult.

    PubMed

    KleinHeerenbrink, Marco; Hedenström, Anders

    2017-02-06

    To maintain the quality of the feathers, birds regularly undergo moult. It is widely accepted that moult affects flight performance, but the specific aerodynamic consequences have received relatively little attention. Here we measured the components of aerodynamic drag from the wake behind a gliding jackdaw (Corvus monedula) at different stages of its natural wing moult. We found that span efficiency was reduced (lift induced drag increased) and the wing profile drag coefficient was increased. Both effects best correlated with the corresponding reduction in spanwise camber. The negative effects are partially mitigated by adjustments of wing posture to minimize gaps in the wing, and by weight loss to reduce wing loading. By studying the aerodynamic consequences of moult, we can refine our understanding of the emergence of various moulting strategies found among birds.

  16. Bidirectional Bacterial Gliding Motility Powered by the Collective Transport of Cell Surface Proteins

    NASA Astrophysics Data System (ADS)

    Wada, Hirofumi; Nakane, Daisuke; Chen, Hsuan-Yi

    2013-12-01

    The gliding motility of Flavobacterium johnsoniae is driven by moving surface adhesive proteins. Recently, these motility components were observed to travel along a closed loop on the cell surface. The mechanism by which such moving surface adhesins give rise to cell motion remains unknown. On the basis of the unique motility properties of F. johnsoniae, we present a generic model for bidirectional motion of rigidly coupled adhesins, which are propelled in opposite directions. Using analytical and numerical methods, we demonstrate that, for a sufficiently large adhesin speed, bidirectional motion arises from spontaneous symmetry breaking. The model also predicts that, close to the bifurcation point, a weak asymmetry in the binding dynamics is sufficient to facilitate directed motility, indicating that the direction of motion could be sensitively regulated internally in response to inhomogeneity of the environment.

  17. Orbital-Parity Selective Superconducting Pairing Structures of Fe-based Superconductors under Glide Symmetry

    NASA Astrophysics Data System (ADS)

    Lin, Chiahui; Chou, Chung-Pin; Yin, Wei-Guo; Ku, Wei

    2014-03-01

    We show that the superconductivity in Fe-based superconductors consists of zero and finite momentum (π , π , 0) Cooper pairs with the same and different parities of the Fe 3 d orbitals respectively. The former develops the distinct gap structures for each orbital parity, and the latter is characteristic of spin singlet, spacial oddness and time reversal symmetry breaking. This originates from the unit cell containing two Fe atoms and two anions of staggered positioning with respect to the Fe square lattice. The in-plane translation is turned into glide translation, which dictates orbital-parity selective quasiparticles. Such novel pairing structures explain the unusual gap angular modulation on the hole pockets in recent ARPES and STS experiments. Work supported by DOE DE-AC02-98CH10886 and Chinese Academy of Engineering Physics and Ministry of Science and Technology.

  18. Complete genome sequence of the gliding, heparinolytic Pedobacter saltans type strain (113T)

    PubMed Central

    Liolios, Konstantinos; Sikorski, Johannes; Lu, Meagan; Nolan, Matt; Lapidus, Alla; Lucas, Susan; Hammon, Nancy; Deshpande, Shweta; Cheng, Jan-Fang; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne; Pitluck, Sam; Huntemann, Marcel; Ivanova, Natalia; Pagani, Ioanna; Mavromatis, Konstantinos; Ovchinikova, Galina; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Land, Miriam; Hauser, Loren; Brambilla, Evelyne-Marie; Kotsyurbenko, Oleg; Rohde, Manfred; Tindall, Brian J.; Abt, Birte; Göker, Markus; Detter, John C.; Woyke, Tanja; Bristow, James; Eisen, Jonathan A.; 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 genome 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. PMID:22180808

  19. Phalangeal morphology of the paromomyidae (?primates, plesiadapiformes): the evidence for gliding behavior reconsidered.

    PubMed

    Hamrick, M W; Rosenman, B A; Brush, J A

    1999-07-01

    A comparative morphometric analysis of isolated proximal and intermediate phalanges attributed to the paromomyids Ignacius graybullianus and Phenacolemur simonsi was undertaken to test the hypothesis that these fossil phalanges exhibit evidence of a dermopteran-like interdigital patagium. Linear dimensions were collected for the fossil phalanges and a comparative sample of associated proximal and intermediate phalanges representing extant tree squirrels, tree shrews, dermopterans (colugos), gliding rodents and marsupials, and prosimian primates. Quantitative data indicate that the proximal and intermediate phalanges of paromomyids are most similar in their overall shape to those of the dermopteran Cynocephalus. The proximal phalanges of paromomyids and colugos possess well-developed flexor sheath ridges and broad, high shafts, whereas the intermediate phalanges of these taxa are most similar to one another in their trochlear morphology. Discriminant analysis indicates that all of the paromomyid intermediate phalanges resemble those from colugo toes more so than those from colugo fingers. Moreover, the relative length and midshaft proportions of both the proximal and intermediate phalanges of paromomyids closely resemble those of several squirrels that lack an interdigital patagium. The following conclusions are drawn from this study: 1) paromomyids share a number of derived phalangeal features with modern dermopterans that may be indicative of a phylogenetic relationship between them, 2) existing intermediate phalanges of paromomyids are inconsistent with the "mitten gliding" hypothesis because they do not possess the distinctive length and midshaft proportions characteristic of colugo manual intermediate phalanges, and 3) paromomyids share with colugos and the scaly-tailed squirrel Anomalurus several aspects of phalangeal morphology functionally related to frequent vertical clinging and climbing on large-diameter arboreal supports.

  20. Foliage chemistry influences tree choice and landscape use of a gliding marsupial folivore.

    PubMed

    Youngentob, Kara N; Wallis, Ian R; Lindenmayer, David B; Wood, Jeff T; Pope, Matthew L; Foley, William J

    2011-01-01

    The chemical quality of forage may determine landscape use and habitat quality for some herbivorous species. However, studies that investigate the relationship between foliar chemistry and foraging choices in wild vertebrates are rare. Petauroides volans (the greater glider) is unique among Australian marsupial folivores because it glides. It also frequently consumes foliage from both major Eucalyptus subgenera, Eucalyptus (common name "monocalypt") and Symphyomyrtus (common name "symphyomyrtle"), which differ markedly in their foliar chemistry. Such differences are thought to be a product of co-evolution that also led to guild-specific plant secondary metabolite (PSM) specialization among other marsupial eucalypt folivores. To explore whether foliar chemistry influences tree use, we analyzed foliage from eucalypt trees in which we observed P. volans during a radio tracking study and from eucalypt trees in which animals were never observed. We used a combination of chemical assays and near infrared spectrophotometry (NIRS) to determine concentrations of nitrogen (N), in vitro available nitrogen (AvailN), and in vitro digestible dry matter (DDM) from foliage sampled from the monocalypt and symphyomyrtle species, and total formylated phloroglucinol compounds (FPCs) and sideroxylonals (a class of FPCs) from the symphyomyrtle species (FPCs do not occur in monocalypts). Tree size and spatially-dependent, intraspecific variations in sideroxylonals and DDM concentrations in the symphyomyrtle foliage and of N, AvailN, and DDM in the monocalypt species were important indicators of tree use and habitat suitability for P. volans. The results i) demonstrate that guild-specific PSMs do not always lead to guild-specific foraging; ii) provide a compelling co-evolutionary case for the development of gliding in P. volans; and iii) have implications for the management and conservation of this and other folivorous species.