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Sample records for adca type iii

  1. SCA2 is not a major locus for ADCA type I in French families

    SciTech Connect

    Cancel, G.; Stevanin, G.; Duerr, A.; Penet, C.

    1995-10-09

    Autosomal dominant cerebellar ataxias (ADCA) of type I, a group of clinically heterogeneous neurodegenerative disorders, are known to be genetically heterogeneous since a second locus for ADCA type I (SCA2) has been identified on the long arm of chromosome 12. Linkage analysis was performed in 7 French ADCA type I families in order to estimate its frequency. We analysed 121 individuals, 39 of whom were affected. In 6 families, the SCA2 candidate interval, spanning 12.8 cM, was excluded by bi- and multipoint analysis. In one family (SAL-315), however, the maximal positive lod score reached 2.03 at the D12S79 locus. A posterior probability of 94% in favor of linkage to SCA2 was calculated by homogeneity analysis. The clinical profile of this family was similar to that of previously described SCA1 and non-SCA1 families, except that dementia was observed in 2 out of 6 patients. This may be a clinical idiosyncrasy in this family and was insufficient for a genotype-phenotype correlation. 14 refs., 1 fig., 1 tab.

  2. Autosomal dominant cerebellar ataxia type III: a review of the phenotypic and genotypic characteristics.

    PubMed

    Fujioka, Shinsuke; Sundal, Christina; Wszolek, Zbigniew K

    2013-01-01

    Autosomal Dominant Cerebellar Ataxia (ADCA) Type III is a type of spinocerebellar ataxia (SCA) classically characterized by pure cerebellar ataxia and occasionally by non-cerebellar signs such as pyramidal signs, ophthalmoplegia, and tremor. The onset of symptoms typically occurs in adulthood; however, a minority of patients develop clinical features in adolescence. The incidence of ADCA Type III is unknown. ADCA Type III consists of six subtypes, SCA5, SCA6, SCA11, SCA26, SCA30, and SCA31. The subtype SCA6 is the most common. These subtypes are associated with four causative genes and two loci. The severity of symptoms and age of onset can vary between each SCA subtype and even between families with the same subtype. SCA5 and SCA11 are caused by specific gene mutations such as missense, inframe deletions, and frameshift insertions or deletions. SCA6 is caused by trinucleotide CAG repeat expansions encoding large uninterrupted glutamine tracts. SCA31 is caused by repeat expansions that fall outside of the protein-coding region of the disease gene. Currently, there are no specific gene mutations associated with SCA26 or SCA30, though there is a confirmed locus for each subtype. This disease is mainly diagnosed via genetic testing; however, differential diagnoses include pure cerebellar ataxia and non-cerebellar features in addition to ataxia. Although not fatal, ADCA Type III may cause dysphagia and falls, which reduce the quality of life of the patients and may in turn shorten the lifespan. The therapy for ADCA Type III is supportive and includes occupational and speech modalities. There is no cure for ADCA Type III, but a number of recent studies have highlighted novel therapies, which bring hope for future curative treatments. PMID:23331413

  3. Zn2+ Uptake in Streptococcus pyogenes: Characterization of adcA and lmb Null Mutants.

    PubMed

    Tedde, Vittorio; Rosini, Roberto; Galeotti, Cesira L

    2016-01-01

    An effective regulation of metal ion homeostasis is essential for the growth of microorganisms in any environment and in pathogenic bacteria is strongly associated with their ability to invade and colonise their hosts. To gain a better insight into zinc acquisition in Group A Streptococcus (GAS) we characterized null deletion mutants of the adcA and lmb genes of Streptococcus pyogenes strain MGAS5005 encoding the orthologues of AdcA and AdcAII, the two surface lipoproteins with partly redundant roles in zinc homeostasis in Streptococcus pneumoniae. Null adcA and lmb mutants were analysed for their capability to grow in zinc-depleted conditions and were found to be more susceptible to zinc starvation, a phenotype that could be rescued by the addition of Zn2+ ions to the growth medium. Expression of AdcA, Lmb and HtpA, the polyhistidine triad protein encoded by the gene adjacent to lmb, during growth under conditions of limited zinc availability was examined by Western blot analysis in wild type and null mutant strains. In the wild type strain, AdcA was always present with little variation in expression levels between conditions of excess or limited zinc availability. In contrast, Lmb and HtpA were expressed at detectable levels only during growth in the presence of low zinc concentrations or in the null adcA mutant, when expression of lmb is required to compensate for the lack of adcA expression. In the latter case, Lmb and HtpA were overexpressed by several fold, thus indicating that also in GAS AdcA is a zinc-specific importer and, although it shares this function with Lmb, the two substrate-binding proteins do not show fully overlapping roles in zinc homeostasis.

  4. Zn2+ Uptake in Streptococcus pyogenes: Characterization of adcA and lmb Null Mutants

    PubMed Central

    Tedde, Vittorio; Rosini, Roberto; Galeotti, Cesira L.

    2016-01-01

    An effective regulation of metal ion homeostasis is essential for the growth of microorganisms in any environment and in pathogenic bacteria is strongly associated with their ability to invade and colonise their hosts. To gain a better insight into zinc acquisition in Group A Streptococcus (GAS) we characterized null deletion mutants of the adcA and lmb genes of Streptococcus pyogenes strain MGAS5005 encoding the orthologues of AdcA and AdcAII, the two surface lipoproteins with partly redundant roles in zinc homeostasis in Streptococcus pneumoniae. Null adcA and lmb mutants were analysed for their capability to grow in zinc-depleted conditions and were found to be more susceptible to zinc starvation, a phenotype that could be rescued by the addition of Zn2+ ions to the growth medium. Expression of AdcA, Lmb and HtpA, the polyhistidine triad protein encoded by the gene adjacent to lmb, during growth under conditions of limited zinc availability was examined by Western blot analysis in wild type and null mutant strains. In the wild type strain, AdcA was always present with little variation in expression levels between conditions of excess or limited zinc availability. In contrast, Lmb and HtpA were expressed at detectable levels only during growth in the presence of low zinc concentrations or in the null adcA mutant, when expression of lmb is required to compensate for the lack of adcA expression. In the latter case, Lmb and HtpA were overexpressed by several fold, thus indicating that also in GAS AdcA is a zinc-specific importer and, although it shares this function with Lmb, the two substrate-binding proteins do not show fully overlapping roles in zinc homeostasis. PMID:27031880

  5. Type III Hyperlipoproteinaemia

    PubMed Central

    Borrie, Peter

    1969-01-01

    Eighteen patients with type III hyperlipoproteinaemia, diagnosed on the basis of skin lesions, serum lipids, and lipoprotein electrophoresis, have been fully investigated over a period of 15 years. The incidence of coronary artery disease was only slightly increased, and was not increased at all among first-degree relatives. Peripheral occlusive arterial disease was probably more common. An increased incidence of carbohydrate intolerance was found in neither the patients nor their relatives. The effects of treatment on the skin were uniformly good. ImagesFig. 1Fig. 2 PMID:5783124

  6. Cranial mononeuropathy III - diabetic type

    MedlinePlus

    ... gov/ency/article/000692.htm Cranial mononeuropathy III - diabetic type To use the sharing features on this page, please enable JavaScript. Cranial mononeuropathy III -- diabetic type -- is usually a complication of diabetes that causes ...

  7. Bursts of Type III and Type V

    NASA Astrophysics Data System (ADS)

    Suzuki, S.; Dulk, G. A.

    The observational database on Types III and V solar radio bursts is summarized and used as a basis for developing analytical models of the observed phenomena. Type III events are characterized by a rapid drift from high to low frequencies, a harmonic structure consisting of F-H pairs, and circular polarization. Type V events last longer than Type III bursts and have a broader bandwidth. Both bursts are thought to arise from the same mechanism. Probable sources of the F-H pairs are characterized, along with the brightness temperature, time profiles, and polarization features typical of Type III and IIIb, structureless Type III and storm Type III bursts. Attention is also given to the interaction between Type III bursts and the coronal magnetic field and to similarities between Type III events and inverted-U and J bursts.

  8. Outcome of tyrosinaemia type III.

    PubMed

    Ellaway, C J; Holme, E; Standing, S; Preece, M A; Green, A; Ploechl, E; Ugarte, M; Trefz, F K; Leonard, J V

    2001-12-01

    Tyrosinaemia type III is a rare disorder caused by a deficiency of 4-hydroxyphenylpyruvate dioxygenase, the second enzyme in the catabolic pathway of tyrosine. The majority of the nine previously reported patients have presented with neurological symptoms after the neonatal period, while others detected by neonatal screening have been asymptomatic. All have had normal liver and renal function and none has skin or eye abnormalities. A further four patients with tyrosinaemia type III are described. It is not clear whether a strict low tyrosine diet alters the natural history of tyrosinaemia type III, although there remains a suspicion that treatment may be important, at least in infancy.

  9. The type III secretion injectisome.

    PubMed

    Cornelis, Guy R

    2006-11-01

    The type III secretion injectisome is a complex nanomachine that allows bacteria to deliver protein effectors across eukaryotic cellular membranes. In recent years, significant progress has been made in our understanding of its structure, assembly and mode of operation. The principal structural components of the injectisome, from the base located in the bacterial cytosol to the tip of the needle protruding from the cell surface, have been investigated in detail. The structures of several constituent proteins were solved at the atomic level and important insights into the assembly process have been gained. However, despite the ongoing concerted efforts of molecular and structural biologists, the role of many of the constituent components of this nanomachine remain unknown. PMID:17041629

  10. On Type III plessite in chondrites

    NASA Astrophysics Data System (ADS)

    Knox, R., Jr.

    1980-03-01

    Questions are raised concerning the possible sources of heat necessary for converting martensite to coarse Type III plessite in ordinary chondrites. It is suggested that the unusual Type III plesite in the Kingfisher, Oklahoma black chondrite was formed by partial homogenization of preexisting Type III plessite as a result of shock reheating of the metal into the gamma field of the Fe-Ni phase diagram, rather than by decomposition of shock reheated prior martensite in the alpha + gamma field, as originally proposed by Taylor and Heymann. Because martensite is sporadically distributed within Kingfisher plessite it is suggested that microstructures of this kind be called Type II-III plessite.

  11. Solar type III radio burst emission process

    SciTech Connect

    Wentzel, D.G.

    1982-05-01

    The interplanetary type III radio emission has been explained by two qualitatively different nonlinear plasma processes, invoking respectively one- and two-dimensional evolution of plasma wave packets. This paper asks: Is solar coronal type III emission consistent with plasma solitons evolving in one dimension. Although the answer is at best a qualified yes, the theory suggests observational questions that have attracted little attention so far.

  12. Impact analysis of Minuteman III Payload Transporter Type III

    SciTech Connect

    Stirbis, P.P.

    1993-12-01

    An analysis of the impact of the Minuteman III Payload Transporter Type III into a nonyielding target at 46 m.p.h. and 30 m.p.h., and into a yielding target at 46 m.p.h. is presented. The analysis considers the structural response of the tiedown system which secures the Minuteman III re-entry system to the floor of the payload transporter. A finite element model of the re-entry system, its tiedown system, which includes tie-rods and shear pins, and the pallet plate which is attached to the transporter floating plate, was constructed. Because accelerations of the payload transporter are not known, acceleration data from one-quarter scale testing of the Safe Secure Trailer was used to investigate the response of the tiedown system. These accelerations were applied to the pallet plate. The ABAQUS computer code was used to predict the forces in the members of the tiedown system.

  13. Mechanistic insights into type III restriction enzymes.

    PubMed

    Raghavendra, Nidhanapati K; Bheemanaik, Shivakumara; Rao, Desirazu N

    2012-01-01

    Type III restriction-modification (R-M) enzymes need to interact with two separate unmethylated DNA sequences in indirectly repeated, head-to-head orientations for efficient cleavage to occur at a defined location next to only one of the two sites. However, cleavage of sites that are not in head-to-head orientation have been observed to occur under certain reaction conditions in vitro. ATP hydrolysis is required for the long-distance communication between the sites prior to cleavage. Type III R-M enzymes comprise two subunits, Res and Mod that form a homodimeric Mod2 and a heterotetrameric Res2Mod2 complex. The Mod subunit in M2 or R2M2 complex recognizes and methylates DNA while the Res subunit in R2M2 complex is responsible for ATP hydrolysis, DNA translocation and cleavage. A vast majority of biochemical studies on Type III R-M enzymes have been undertaken using two closely related enzymes, EcoP1I and EcoP15I. Divergent opinions about how the long-distance interaction between the recognition sites exist and at least three mechanistic models based on 1D- diffusion and/or 3D- DNA looping have been proposed.

  14. Sources of type III solar microwave bursts

    NASA Astrophysics Data System (ADS)

    Zhdanov, Dmitriy; Lesovoi, Sergey; Tokhchukova, Susanna

    2016-06-01

    Microwave fine structures allow us to study plasma evolution in an energy release region. The Siberian Solar Radio Telescope (SSRT) is a unique instrument designed to examine fine structures at 5.7 GHz. A complex analysis of data from RATAN-600, 4-8 GHz spectropolarimeter, and SSRT, simultaneously with extreme UV data, made it possible to localize sources of III type microwave drift bursts in August 10, 2011 event within the entire frequency band of burst occurrences, as well as to determine the most probable region of primary energy release. To localize sources of III type bursts from RATAN-600 data, an original method for data processing has been worked out. At 5.7 GHz, the source of bursts was determined along two coordinates whereas at 4.5, 4.7, 4.9, 5.1, 5.3, 5.5 and 6.0 GHz, their locations were identified along one coordinate. The size of the burst source at 5.1 GHz was found to be maximum as compared to source sizes at other frequencies.

  15. Type III secretion systems and pathogenicity islands.

    PubMed

    Winstanley, C; Hart, C A

    2001-02-01

    Some bacterial pathogens have evolved by acquiring pathogenicity islands (PIs), which are clusters of genes encoding virulence traits. PIs encoding the secretion of effector molecules via type III secretion (TTS) systems have been discovered in several gram-negative pathogens. TTS systems are involved in contact-dependent secretion of virulence factors and can facilitate delivery of toxins directly into target cells. The expanding list of bacteria found to contain clusters of TTS genes includes members of the genera Yersinia, Salmonella, Shigella, Escherichia, Pseudomonas, Bordetella, Burkholderia, Chlamydia and a number of plant pathogens or symbionts. This review discusses the current knowledge of the role of TTS PIs in pathogenicity, the genetic organisation and evolution of such systems,and the potential for using TTS systems as targets for novel treatments.

  16. Solar Type III Radio Bursts: Directivity Characteristics

    NASA Astrophysics Data System (ADS)

    Thejappa, G.; MacDowall, R. J.

    2015-09-01

    Type III radio bursts are a group of fast drifting radio emissions associated with solar flares. These radio emissions are believed to be excited at the fundamental and second harmonic of the electron plasma frequency, fpe by the electron beam excited Langmuir waves through a mechanism called the plasma mechanism. This mechanism attributes the dipole and quadrupole beam patterns for the fundamental and harmonic emissions. To verify these predictions, we analyze the simultaneous observations of type III radio bursts by the STEREO A, B and Wind spacecraft located at different vantage points in the ecliptic plane, and determine their normalized peak intensities (directivity factors) at each spacecraft using their time profiles. Assuming that the sources of these bursts are located on the Parker spiral magnetic field lines emerging from the associated active regions, we estimate the angles between the magnetic field directions and the lines connecting the sources to the spacecraft (viewing angles). Based on the plots of the directivity factors versus the viewing angles, one can divide these bursts into (1) intense bursts emitted into a narrow cone centered around the tangent to the magnetic field, and (2) relatively weaker bursts emitting into a wider cone centered around the tangent to the magnetic field. We compute the distributions of ray trajectories emitted by an isotropic point source and show that the refraction focuses the fundamental and harmonic emissions into narrow and wider cones, respectively. The comparison of these distributions with observations indicates that the intense bursts visible to a narrow range of angles around the tangent to the magnetic field probably correspond to the fundamental, and the relatively weaker bursts visible to a wide range of angles probably are the harmonic emissions.

  17. DECIMETRIC TYPE III BURSTS: GENERATION AND PROPAGATION

    SciTech Connect

    Li, B.; Cairns, Iver H.; Robinson, P. A.; Yan, Y. H.

    2011-09-01

    Simulations are presented for decimetric type III radio bursts at 2f{sub p} , where f{sub p} is the local electron plasma frequency. The simulations show that 2f{sub p} radiation can be observed at Earth in two scenarios for the radiation's generation and propagation. In Scenario A, radiation is produced and propagates in warm plasmas in the lower corona that are caused by previous magnetic reconnection outflows and/or chromospheric evaporation. In Scenario B radiation is generated in normal plasmas, then due to its natural directivity pattern and refraction, radiation partly propagates into nearby regions, which are hot because of previous reconnection/evaporation. The profiles of plasma density n{sub e} (r) and electron temperature T{sub e} (r) in the lower corona (r - R{sub sun} {approx}< 100 Mm) are found to be crucial to whether radiation can be produced and escape at observable levels against the effects of free-free absorption, where r is the heliocentric distance. Significantly, the observed wide ranges of radiation properties (e.g., drift rates) require n{sub e} (r) with a large range of scale heights h{sub s} , consistent nonetheless for Scenario B with short observed EUV loops. This is relevant to problems with large h{sub s} inferred from tall EUV loops. The simulations suggest: (1) n{sub e} (r) with small h{sub s} , such as n{sub e} (r){proportional_to}(r - R{sub sun}){sup -2.38} for flaring regions, are unexpectedly common deep in the corona. This result is consistent with recent work on n{sub e} (r) for r {approx} (1.05-2)R{sub sun} extracted from observed metric type IIIs. (2) The dominance of reverse-slope bursts over normal bursts sometimes observed may originate from asymmetric reconnection/acceleration, which favors downgoing beams.

  18. Diverse intracellular pathogens activate type III interferon expression from peroxisomes.

    PubMed

    Odendall, Charlotte; Dixit, Evelyn; Stavru, Fabrizia; Bierne, Helene; Franz, Kate M; Durbin, Ann Fiegen; Boulant, Steeve; Gehrke, Lee; Cossart, Pascale; Kagan, Jonathan C

    2014-08-01

    Type I interferon responses are considered the primary means by which viral infections are controlled in mammals. Despite this view, several pathogens activate antiviral responses in the absence of type I interferons. The mechanisms controlling type I interferon-independent responses are undefined. We found that RIG-I like receptors (RLRs) induce type III interferon expression in a variety of human cell types, and identified factors that differentially regulate expression of type I and type III interferons. We identified peroxisomes as a primary site of initiation of type III interferon expression, and revealed that the process of intestinal epithelial cell differentiation upregulates peroxisome biogenesis and promotes robust type III interferon responses in human cells. These findings highlight the importance of different intracellular organelles in specific innate immune responses.

  19. Periodicities of Interplanetary Solar Type III radio bursts occurrence

    NASA Astrophysics Data System (ADS)

    Maksimovic, Milan; Navrer-Agasson, Anyssa; Sperone-Longin, Damien; Bonnin, Xavier

    2015-04-01

    We have analyzed 15 years of solar radio observations by the Wind spacecraft in order to detect automatically the Interplanetary Solar Type III radio bursts occurrence. We then compare the daily number of type III radio emissions with the daily number of sunspots. We find, as expected, a very good correlation between the two quantities. We investigate then for periodicities in the daily occurrence of type III bursts by applying a wavelet analysis and compare these periodicities to the ones obtained with the sunspots. We observe a typical Rieger-Type period of about 150 days for both the Type IIIs and the sunspots, with a temporal location of the maximum of this periodicity which is however different for the two data sets. We discuss this difference and compare our results to previous similar studies applied on ground based observations of Type III activity.

  20. Imprints of coronal temperature disturbances on type III bursts

    NASA Astrophysics Data System (ADS)

    Li, Bo; Robinson, Peter

    The electron temperature Te and ion temperature Ti in the corona vary with time and loca-tion, due to transient and persistent activity on the Sun. The effects of spatially localized disturbances in Te and Ti on coronal type III radio bursts are simulated. The disturbances are superimposed on monotonically varying temperature backgrounds and arise from spatially confined solar activity. Qualitatively and quantitatively different imprints are found on the curve of the maximum flux versus frequency of type III bursts, because of the disturbances in Te and Ti . The results indicate that nonthermal coronal type III bursts offer a new tool to probe and distinguish between spatially localized structures of Te and Ti along the paths of type III beams. Furthermore, localized temperature disturbances may be responsible for some fine structures in type III bursts, e.g., striae in type IIIb bursts in the presence of multiple, localized temperature disturbances.

  1. Diverse intracellular pathogens activate Type III Interferon expression from peroxisomes

    PubMed Central

    Odendall, Charlotte; Dixit, Evelyn; Stavru, Fabrizia; Bierne, Helene; Franz, Kate M.; Fiegen, Ann; Boulant, Steeve; Gehrke, Lee; Cossart, Pascale; Kagan, Jonathan C.

    2014-01-01

    Type I Interferon (IFN) responses are considered the primary means by which viral infections are controlled in mammals. Despite this view, several pathogens activate antiviral responses in the absence of Type I IFNs. The mechanisms controlling Type I IFN-independent responses are undefined. We have found that RIG-I like Receptors (RLRs) induce Type III IFN expression in a variety of human cell types, and identified factors that differentially regulate Type I and III IFN expression. We identified peroxisomes as a primary site that initiates Type III IFN expression, and revealed that the process of intestinal epithelial cell differentiation upregulates peroxisome biogenesis and promotes robust Type III IFN responses in human cells. These findings highlight the interconnections between innate immunity and cell biology. PMID:24952503

  2. TYPE III RADIO BURSTS PERTURBED BY WEAK CORONAL SHOCKS

    SciTech Connect

    Li, B.; Cairns, Iver H.

    2012-07-10

    Some type III bursts are observed to undergo sudden flux modifications, e.g., reductions and intensifications, when type III beams cross shocks in the upper corona or solar wind. First simulations are presented for type III bursts perturbed by weak coronal shocks, which type III beams traverse. The simulations incorporate spatially localized jumps in plasma density and electron and ion temperatures downstream of a shock. A shock is predicted to produce significant modulations to a type III burst: (1) a broadband flux reduction or frequency gap caused by the shock's density jump, (2) a narrowband flux intensification originating from where the downstream plasma density locally has a small gradient, (3) a possible intensification from the shock front or just upstream, and (4) changes in the frequency drift rate profile and the temporal evolution of radiation flux at frequencies corresponding to the shocked plasma. The modulations are caused primarily by fundamental modifications to the radiation processes in response to the shocked density and temperatures. The predicted intensifications and reductions appear qualitatively consistent with the available small number of reported observations, although it is unclear how representative these observations are. It is demonstrated that a weak shock can cause an otherwise radio-quiet type III beam to produce observable levels of narrowband radio emission. The simulations suggest that type III bursts with frequency-time fine structures may provide a tool to probe shocks in the corona and solar wind, especially for weak shocks that do not radiate by themselves.

  3. Extrapyramidal Symptoms and Medication Use in Mucopolysaccharidosis Type III

    ERIC Educational Resources Information Center

    Tchan, Michel C.; Sillence, David

    2009-01-01

    Background: We report the case of a 16-year-old male with Mucopolysaccharidosis III type A (Sanfilippo syndrome) who was commenced on risperidone for behaviour management. He rapidly developed extrapyramidal symptoms that have not resolved. Method: The medication histories of 20 patients with Mucopolysaccharidosis III seen at a Lysosomal Storage…

  4. Plotting Formula for Pearson Type III Distribution Considering Historical Information.

    ERIC Educational Resources Information Center

    Nguyen, Van Thanh-Van; In-na, Nophadol

    1992-01-01

    Proposes a plotting position formula for the Pearson type III distribution in the analysis of historical flood information. Presents results of a numerical example using actual flood data to confirm the appropriateness of the plotting formula. (24 references) (MDH)

  5. Decametric and hectometric Solar Type III bursts at Saturn's orbit

    NASA Astrophysics Data System (ADS)

    Boudjada, Mohammed Y.; Sawas, Sami; Galopeau, Patrick H. M.; Maksimovic, Milan

    2015-04-01

    We report on solar radio bursts observed by RPWS experiment onboard Cassini spacecraft. We consider Type III solar bursts observed in the frequency range from 1 MHz to 16 MHz. Those bursts are probably generated in the solar corona and the interplanetary medium. We show that the Type III burst occurrence is depending on the solar activity. We attempt to localize the regions where the Type III burst is probably emitted. We consider that the electrons at the origin of the Solar Type III bursts follow the interplanetary magnetic field. The trajectory is an Archimedean spiral contained in the ecliptic plane. We discuss our results taking into consideration on the one hand the spacecraft positions with regards to the source location, and on the other hand the temporal and spectral radio beam variation when combining Cassini and Wind observations.

  6. Neuronal Neuregulin 1 type III directs Schwann cell migration

    PubMed Central

    Perlin, Julie R.; Lush, Mark E.; Stephens, W. Zac; Piotrowski, Tatjana; Talbot, William S.

    2011-01-01

    During peripheral nerve development, each segment of a myelinated axon is matched with a single Schwann cell. Tight regulation of Schwann cell movement, proliferation and differentiation is essential to ensure that these glial cells properly associate with axons. ErbB receptors are required for Schwann cell migration, but the operative ligand and its mechanism of action have remained unknown. We demonstrate that zebrafish Neuregulin 1 (Nrg1) type III, which signals through ErbB receptors, controls Schwann cell migration in addition to its previously known roles in proliferation and myelination. Chimera analyses indicate that ErbB receptors are required in all migrating Schwann cells, and that Nrg1 type III is required in neurons for migration. Surprisingly, expression of the ligand in a few axons is sufficient to induce migration along a chimeric nerve constituted largely of nrg1 type III mutant axons. These studies also reveal a mechanism that allows Schwann cells to fasciculate axons regardless of nrg1 type III expression. Time-lapse imaging of transgenic embryos demonstrated that misexpression of human NRG1 type III results in ectopic Schwann cell migration, allowing them to aberrantly enter the central nervous system. These results demonstrate that Nrg1 type III is an essential signal that controls Schwann cell migration to ensure that these glia are present in the correct numbers and positions in developing nerves. PMID:21965611

  7. Heterogeneity of collagens in rabbit cornea: type III collagen

    SciTech Connect

    Cintron, C.; Hong, B.S.; Covington, H.I.; Macarak, E.J.

    1988-05-01

    Whole neonate rabbit corneas and adult corneas containing 2-week-old scars were incubated in the presence of (/sup 14/C) glycine. Radiolabeled collagen extracted from the corneas and scar tissue were analyzed by sodium dodecylsulfate/polyacrylamide gel electrophoresis and fluorography to determine the types and relative quantity of collagen polypeptides present and synthesized by these tissues. In addition to other collagen types, type III was found in both neonate cornea and scar tissue from adult cornea, albeit in relatively small quantities. Type III collagen in normal cornea was associated with the residue after pepsin digestion and formic acid extraction of the tissue, and the same type of collagen was extracted from scar tissue after similar treatment. Type III collagen-specific monoclonal antibody bound to developing normal corneas and healing adult tissue sections, as determined by immunofluorescence. Antibody binding was localized to the endothelium and growing Descemet's membrane in fetal and neonate corneas, and restricted to the most posterior region of the corneal scar tissue. Although monoclonal antibody to keratan sulfate, used as a marker for stromal fibroblasts, bound to most of the scar tissue, the antibody failed to bind to the posterior scar tissue positive for type III collagen. We conclude that endothelial cells from fetal and neonate rabbit cornea and endothelium-derived fibroblasts from healing wounds of adult cornea synthesize and deposit type III collagen. Moreover, this collagen appears to be incorporated into the growing Descemet's membrane of normal corneas and narrow posterior portion of the scar tissue.

  8. Imprints of coronal temperature disturbances on type III bursts

    NASA Astrophysics Data System (ADS)

    Li, B.; Cairns, I. H.; Robinson, P. A.

    2010-02-01

    The electron temperature T_e and ion temperature T_i in the corona vary with time and location, due to transient and persistent activity on the Sun. The effects of spatially localized disturbances in T_e and T_i on coronal type III radio bursts are simulated. The disturbances are superimposed on monotonically varying temperature backgrounds and arise from spatially confined solar activity, Qualitatively and quantitatively different imprints are found on the curve of the maximum flux versus frequency of type III bursts, because of the disturbances in T_e and T_i. The results indicate that nonthermal coronal type III bursts offer a new tool to probe and distinguish between spatially localized structures of T_e and T_i along the paths of type III beams. Furthermore, localized temperature disturbances may be responsible for some fine structures in type III bursts, e.g., striae in type IIIb bursts in the presence of multiple, localized temperature disturbances.

  9. CAR flows on type III factors and their extendability

    NASA Astrophysics Data System (ADS)

    Bikram, Panchugopal

    2014-11-01

    In this paper we prove that the CAR flows on type III factors arising from a large class of quasi-free states are not extendable, in the sense of Bikram, Izumi, Srinivasan and Sunder.8 As a consequence, CAR flows and CCR flows on type III factors are not cocycle conjugate. This is in sharp contrast with the situation for the type I∞ factor, for which CAR and CCR flows are in fact conjugate. In addition, we also compute the super-product systems associated to CAR flows.

  10. Unusual Type III Bursts at the Decametre Wavelengths

    NASA Astrophysics Data System (ADS)

    Dorovskyy, V. V.; Melnik, V. N.; Konovalenko, A. A.; Rucker, H. O.; Abranin, E. P.; Lecacheux, A.

    It is currently accepted that the dependences of frequency drift rate and instant duration of type III bursts on frequency follow a monotonic function. The observations carried out during summer months of 2002-2006 by the world largest decameter wavelength radio telescope UTR-2 in frequency band 10-30 MHz show that sometimes these dependences may have a jump at some frequency, when the steepness of the dependence changes step-wise. In this paper the results of observations of such unusual type III bursts are given. Since the dynamic spectrum of such bursts resembles a dog's leg we call them "dog-leg" type III bursts. More than a hundred of these "dog-leg" bursts were observed during 5 years. The parameters of the 41 bursts observed in 2002 were defined and statistically analyzed. The fact that "dog-leg" type III bursts are observed on the background of standard type III bursts allows to exclude any instrumental component of the observed phenomena.

  11. Phytopathogen type III effector weaponry and their plant targets

    PubMed Central

    Block, Anna; Li, Guangyong; Fu, Zheng Qing; Alfano, James R.

    2008-01-01

    Summary Phytopathogenic bacteria suppress plant innate immunity and promote pathogenesis by injecting proteins called type III effectors into plant cells using a type III protein secretion system. These type III effectors use at least three major strategies to alter host responses. One strategy is to alter host protein turnover, either by direct cleavage or by modulating ubiquitination and targeting to the 26S proteasome. Another strategy involves alteration of RNA metabolism by transcriptional activation or ADP-ribosylation of RNA-binding proteins. A third major strategy is to inhibit the kinases involved in plant defence signalling, either by removing phosphates or by direct inhibition. The wide array of strategies bacterial pathogens employ to suppress innate immunity suggest that circumvention of innate immunity is critical for bacterial pathogenicity of plants. PMID:18657470

  12. Clumpy Langmuir waves in type III solar radio bursts

    NASA Technical Reports Server (NTRS)

    Melrose, D. B.; Cairns, I. H.; Dulk, G. A.

    1986-01-01

    A model is developed for type III radio emission in the interplanetary medium based on recent data on Langmuir waves, associated with ion sound waves, density fluctuations in the interplanetary plasma, streaming electrons and radio emission. In this model, Langmuir wave growth is suppressed by refraction in field-aligned density irregularities except near density minima where clumps of Langmuir waves form. Quasi-linear relaxation limits the growth of the Langmuir waves in the clumps. The radio emission, which is attributed to coalescence of the Langmuir waves with associated ion sound waves, saturates at a brightness temperature equal to the effective temperature of the Langmuir waves, estimated to be between 10 to the 15th and 10 to the 16th K from obserrvational data. The model is consistent with all the relevant data on type III events. In particular, it accounts naturally for observed brightness temperatures of type III bursts.

  13. Assessment of Sleep in Children with Mucopolysaccharidosis Type III

    PubMed Central

    Mahon, Louise Victoria; Lomax, Michelle; Grant, Sheena; Cross, Elaine; Hare, Dougal Julian; Wraith, James Ed; Jones, Simon; Bigger, Brian; Langford-Smith, Kia; Canal, Maria

    2014-01-01

    Sleep disturbances are prevalent in mucopolysaccharidosis Type III (MPS III), yet there is a lack of objective, ecologically valid evidence detailing sleep quantity, quality or circadian system. Eight children with MPS III and eight age-matched typically developing children wore an actigraph for 7–10 days/nights. Saliva samples were collected at three time-points on two separate days, to permit analysis of endogenous melatonin levels. Parents completed a sleep questionnaire and a daily sleep diary. Actigraphic data revealed that children with MPS III had significantly longer sleep onset latencies and greater daytime sleep compared to controls, but night-time sleep duration did not differ between groups. In the MPS III group, sleep efficiency declined, and sleep onset latency increased, with age. Questionnaire responses showed that MPS III patients had significantly more sleep difficulties in all domains compared to controls. Melatonin concentrations showed an alteration in the circadian system in MPS III, which suggests that treatment for sleep problems should attempt to synchronise the sleep-wake cycle to a more regular pattern. Actigraphy was tolerated by children and this monitoring device can be recommended as a measure of treatment success in research and clinical practice. PMID:24504123

  14. Bacterial nanomachines: the flagellum and type III injectisome.

    PubMed

    Erhardt, Marc; Namba, Keiichi; Hughes, Kelly T

    2010-11-01

    The bacterial flagellum and the virulence-associated injectisome are complex, structurally related nanomachines that bacteria use for locomotion or the translocation of virulence factors into eukaryotic host cells. The assembly of both structures and the transfer of extracellular proteins is mediated by a unique, multicomponent transport apparatus, the type III secretion system. Here, we discuss the significant progress that has been made in recent years in the visualization and functional characterization of many components of the type III secretion system, the structure of the bacterial flagellum, and the injectisome complex. PMID:20926516

  15. Tyrosinemia Type III detected via neonatal screening: management and outcome.

    PubMed

    Heylen, Evelyne; Scherer, Gerd; Vincent, Marie-Françoise; Marie, Sandrine; Fischer, Judith; Nassogne, Marie-Cécile

    2012-11-01

    Tyrosinemia Type III is caused by the deficiency of 4-hydroxyphenylpyruvate dioxygenase (4-HPPD), an enzyme involved in the catabolic pathway of tyrosine. To our knowledge, only a few patients presenting with this disease have been described in the literature, and the clinical phenotype remains variable and unclear. We report the case of a boy with tyrosinemia Type III detected using neonatal screening, who is homozygous for the splice donor mutation IVS11+1G>A in intron 11 of the HPD gene. At the age of 30 months, the boy's outcome under mild protein restriction was characterized by normal growth and psychomotor development.

  16. Bacterial nanomachines: the flagellum and type III injectisome.

    PubMed

    Erhardt, Marc; Namba, Keiichi; Hughes, Kelly T

    2010-11-01

    The bacterial flagellum and the virulence-associated injectisome are complex, structurally related nanomachines that bacteria use for locomotion or the translocation of virulence factors into eukaryotic host cells. The assembly of both structures and the transfer of extracellular proteins is mediated by a unique, multicomponent transport apparatus, the type III secretion system. Here, we discuss the significant progress that has been made in recent years in the visualization and functional characterization of many components of the type III secretion system, the structure of the bacterial flagellum, and the injectisome complex.

  17. Stabilization of electron streams in type III solar radio bursts

    NASA Technical Reports Server (NTRS)

    Papadopoulos, K.; Goldstein, M. L.; Smith, R. A.

    1974-01-01

    We show that the electron streams that give rise to type III solar radio bursts are stable and will not be decelerated while propagating out of the solar corona. The stabilization mechanism depends on the parametric oscillating two-stream instability. Radiation is produced near the fundamental and second harmonic of the local electron plasma frequency. Estimates of the emission at the second harmonic indicate that the wave spectra created by the oscillating two-stream instability can account for the observed intensities of type III bursts.

  18. Exploiting the Biosynthetic Potential of Type III Polyketide Synthases.

    PubMed

    Lim, Yan Ping; Go, Maybelle K; Yew, Wen Shan

    2016-01-01

    Polyketides are structurally and functionally diverse secondary metabolites that are biosynthesized by polyketide synthases (PKSs) using acyl-CoA precursors. Recent studies in the engineering and structural characterization of PKSs have facilitated the use of target enzymes as biocatalysts to produce novel functionally optimized polyketides. These compounds may serve as potential drug leads. This review summarizes the insights gained from research on type III PKSs, from the discovery of chalcone synthase in plants to novel PKSs in bacteria and fungi. To date, at least 15 families of type III PKSs have been characterized, highlighting the utility of PKSs in the development of natural product libraries for therapeutic development. PMID:27338328

  19. Type III restriction-modification enzymes: a historical perspective.

    PubMed

    Rao, Desirazu N; Dryden, David T F; Bheemanaik, Shivakumara

    2014-01-01

    Restriction endonucleases interact with DNA at specific sites leading to cleavage of DNA. Bacterial DNA is protected from restriction endonuclease cleavage by modifying the DNA using a DNA methyltransferase. Based on their molecular structure, sequence recognition, cleavage position and cofactor requirements, restriction-modification (R-M) systems are classified into four groups. Type III R-M enzymes need to interact with two separate unmethylated DNA sequences in inversely repeated head-to-head orientations for efficient cleavage to occur at a defined location (25-27 bp downstream of one of the recognition sites). Like the Type I R-M enzymes, Type III R-M enzymes possess a sequence-specific ATPase activity for DNA cleavage. ATP hydrolysis is required for the long-distance communication between the sites before cleavage. Different models, based on 1D diffusion and/or 3D-DNA looping, exist to explain how the long-distance interaction between the two recognition sites takes place. Type III R-M systems are found in most sequenced bacteria. Genome sequencing of many pathogenic bacteria also shows the presence of a number of phase-variable Type III R-M systems, which play a role in virulence. A growing number of these enzymes are being subjected to biochemical and genetic studies, which, when combined with ongoing structural analyses, promise to provide details for mechanisms of DNA recognition and catalysis.

  20. Kilometric type III radio bursts and interplanetary transients

    SciTech Connect

    MacDowall, R.J.

    1988-01-01

    The first detailed observations and analysis of interplanetary (IP) type III bursts which undergo sudden intensity changes are presented. Two major even categories are studied: cutoffs in which the type III intensity is abruptly reduced (by a factor of 10 or more) at some frequency and remains at the reduced level for all lower frequencies, and narrowband intensifications which frequently occur on the high-frequency edge of a cutoff. Based on their apparent radial velocities as well as their occurrence at the same frequencies as kilometric type II emission, a subset of the sudden intensity change events are demonstrated to be associated with IP shocks. Consequently, they provide a new tool for shock detection in the inner heliosphere. Two causes proposed for the shock associated type III burst cutoffs are enhanced levels of background electrons and pitch-angle scattering. In the vicinities of IP shocks, the observed background levels of electrons with energies greater than 2 keV are frequently enhanced by up to 2 orders of magnitude over ambient levels. The magnetic field fluctuations observed downstream of many shocks are effective in pitch-angle scattering type III electrons. Either of these mechanisms may reduce the effective height of the bump-on-tail distribution, and thereby influence the Langmuir wave growth and evolution. The pre-cutoff intensifications are shown to arise in regions of radial extent {Delta}R/R {approx} 0.1. Consequently, they are not the result of processes local to the shock.

  1. Computational prediction shines light on type III secretion origins

    PubMed Central

    Goldberg, Tatyana; Rost, Burkhard; Bromberg, Yana

    2016-01-01

    Type III secretion system is a key bacterial symbiosis and pathogenicity mechanism responsible for a variety of infectious diseases, ranging from food-borne illnesses to the bubonic plague. In many Gram-negative bacteria, the type III secretion system transports effector proteins into host cells, converting resources to bacterial advantage. Here we introduce a computational method that identifies type III effectors by combining homology-based inference with de novo predictions, reaching up to 3-fold higher performance than existing tools. Our work reveals that signals for recognition and transport of effectors are distributed over the entire protein sequence instead of being confined to the N-terminus, as was previously thought. Our scan of hundreds of prokaryotic genomes identified previously unknown effectors, suggesting that type III secretion may have evolved prior to the archaea/bacteria split. Crucially, our method performs well for short sequence fragments, facilitating evaluation of microbial communities and rapid identification of bacterial pathogenicity – no genome assembly required. pEffect and its data sets are available at http://services.bromberglab.org/peffect. PMID:27713481

  2. Interplanetary density models as inferred from solar Type III bursts

    NASA Astrophysics Data System (ADS)

    Oppeneiger, Lucas; Boudjada, Mohammed Y.; Lammer, Helmut; Lichtenegger, Herbert

    2016-04-01

    We report on the density models derived from spectral features of solar Type III bursts. They are generated by beams of electrons travelling outward from the Sun along open magnetic field lines. Electrons generate Langmuir waves at the plasma frequency along their ray paths through the corona and the interplanetary medium. A large frequency band is covered by the Type III bursts from several MHz down to few kHz. In this analysis, we consider the previous empirical density models proposed to describe the electron density in the interplanetary medium. We show that those models are mainly based on the analysis of Type III bursts generated in the interplanetary medium and observed by satellites (e.g. RAE, HELIOS, VOYAGER, ULYSSES,WIND). Those models are confronted to stereoscopic observations of Type III bursts recorded by WIND, ULYSSES and CASSINI spacecraft. We discuss the spatial evolution of the electron beam along the interplanetary medium where the trajectory is an Archimedean spiral. We show that the electron beams and the source locations are depending on the choose of the empirical density models.

  3. Microwave Type III Pair Bursts in Solar Flares

    NASA Astrophysics Data System (ADS)

    Tan, Baolin; Mészárosová, Hana; Karlický, Marian; Huang, Guangli; Tan, Chengming

    2016-03-01

    A solar microwave type III pair burst is composed of normal and reverse-sloped (RS) burst branches with oppositely fast frequency drifts. It is the most sensitive signature of the primary energy release and electron accelerations in flares. This work reports 11 microwave type III pair events in 9 flares observed by radio spectrometers in China and the Czech Republic at a frequency of 0.80-7.60 GHz during 1994-2014. These type III pairs occurred in flare impulsive and postflare phases with separate frequencies in the range of 1.08-3.42 GHz and a frequency gap of 10-1700 MHz. The frequency drift increases with the separate frequency (fx), the lifetime of each burst is anti-correlated to fx, while the frequency gap is independent of fx. In most events, the normal branches are drifting obviously faster than the RS branches. The type III pairs occurring in flare impulsive phase have lower separate frequencies, longer lifetimes, wider frequency gaps, and slower frequency drifts than that occurring in postflare phase. Also, the latter always has strong circular polarization. Further analysis indicates that near the flare energy release sites the plasma density is about {10}10{--}{10}11 cm-3 and the temperature is higher than 107 K. These results provide new constraints to the acceleration mechanism in solar flares.

  4. Sequence-Based Prediction of Type III Secreted Proteins

    PubMed Central

    Arnold, Roland; Brandmaier, Stefan; Kleine, Frederick; Tischler, Patrick; Heinz, Eva; Behrens, Sebastian; Niinikoski, Antti; Mewes, Hans-Werner; Horn, Matthias; Rattei, Thomas

    2009-01-01

    The type III secretion system (TTSS) is a key mechanism for host cell interaction used by a variety of bacterial pathogens and symbionts of plants and animals including humans. The TTSS represents a molecular syringe with which the bacteria deliver effector proteins directly into the host cell cytosol. Despite the importance of the TTSS for bacterial pathogenesis, recognition and targeting of type III secreted proteins has up until now been poorly understood. Several hypotheses are discussed, including an mRNA-based signal, a chaperon-mediated process, or an N-terminal signal peptide. In this study, we systematically analyzed the amino acid composition and secondary structure of N-termini of 100 experimentally verified effector proteins. Based on this, we developed a machine-learning approach for the prediction of TTSS effector proteins, taking into account N-terminal sequence features such as frequencies of amino acids, short peptides, or residues with certain physico-chemical properties. The resulting computational model revealed a strong type III secretion signal in the N-terminus that can be used to detect effectors with sensitivity of ∼71% and selectivity of ∼85%. This signal seems to be taxonomically universal and conserved among animal pathogens and plant symbionts, since we could successfully detect effector proteins if the respective group was excluded from training. The application of our prediction approach to 739 complete bacterial and archaeal genome sequences resulted in the identification of between 0% and 12% putative TTSS effector proteins. Comparison of effector proteins with orthologs that are not secreted by the TTSS showed no clear pattern of signal acquisition by fusion, suggesting convergent evolutionary processes shaping the type III secretion signal. The newly developed program EffectiveT3 (http://www.chlamydiaedb.org) is the first universal in silico prediction program for the identification of novel TTSS effectors. Our findings will

  5. An EGFR wild type-EGFRvIII-HB-EGF feed forward loop regulates the activation of EGFRvIII

    PubMed Central

    Li, Li; Chakraborty, Sharmistha; Yang, Chin-Rang; Hatanpaa, Kimmo J.; Cipher, Daisha J.; Puliyappadamba, Vineshkumar Thidil; Rehman, Alizeh; Jiwani, Ameena J.; Mickey, Bruce; Madden, Christopher; Raisanen, Jack; Burma, Sandeep; Saha, Debabrata; Wang, Zhixiang; Pingle, Sandeep C.; Kesari, Santosh; Boothman, David A.; Habib, Amyn A.

    2014-01-01

    EGFRvIII is a key oncogene in glioblastoma (GBM). EGFRvIII results from an in frame deletion in the extracellular domain of EGFR, does not bind ligand, and is thought to be constitutively active. While EGFRvIII dimerization is known to activate EGFRvIII, the factors that drive EGFRvIII dimerization and activation are not well understood. Here we present a new model of EGFRvIII activation and propose that oncogenic activation of EGFRvIII in glioma cells is driven by co-expressed activated EGFR wild type (EGFRwt). Increasing EGFRwt leads to a striking increase in EGFRvIII tyrosine phosphorylation and activation while silencing EGFRwt inhibits EGFRvIII activation. Both the dimerization arm and the kinase activity of EGFRwt are required for EGFRvIII activation. EGFRwt activates EGFRvIII by facilitating EGFRvIII dimerization. We have previously identified HB-EGF, a ligand for EGFRwt, as a gene induced specifically by EGFRvIII. In this study we show that HB-EGF, is induced by EGFRvIII only when EGFRwt is present. Remarkably, altering HB-EGF recapitulates the effect of EGFRwt on EGFRvIII activation. Thus, increasing HB-EGF leads to a striking increase in EGFRvIII tyrosine phosphorylation while silencing HB-EGF attenuates EGFRvIII phosphorylation, suggesting that an EGFRvIII-HB-EGF-EGFRwt feed forward loop regulates EGFRvIII activation. Silencing EGFRwt or HB-EGF leads to a striking inhibition of EGFRvIII induced tumorigenicity, while increasing EGFRwt or HB-EGF levels resulted in accelerated EGFRvIII mediated oncogenicity in an orthotopic mouse model. Furthermore, we demonstrate the existence of this loop in human GBM. Thus, our data demonstrate that oncogenic activation of EGFRvIII in GBM is likely maintained by a continuous EGFRwt-EGFRvIII-HBEGF loop, potentially an attractive target for therapeutic intervention. PMID:24077285

  6. A tiny event producing an interplanetary type III burst

    NASA Astrophysics Data System (ADS)

    Alissandrakis, C. E.; Nindos, A.; Patsourakos, S.; Kontogeorgos, A.; Tsitsipis, P.

    2015-10-01

    Aims: We investigate the conditions under which small-scale energy release events in the low corona gave rise to strong interplanetary (IP) type III bursts. Methods: We analyzed observations of three tiny events, detected by the Nançay Radio Heliograph (NRH), two of which produced IP type III bursts. We took advantage of the NRH positioning information and of the high cadence of AIA/SDO data to identify the associated extreme-UV (EUV) emissions. We measured positions and time profiles of the metric and EUV sources. Results: We found that the EUV events that produced IP type III bursts were located near a coronal hole boundary, while the one that did not was located in a closed magnetic field region. In all three cases tiny flaring loops were involved, without any associated mass eruption. In the best observed case, the radio emission at the highest frequency (435 MHz) was displaced by ~55'' with respect to the small flaring loop. The metric type III emission shows a complex structure in space and in time, indicative of multiple electron beams, despite the low intensity of the events. From the combined analysis of dynamic spectra and NRH images, we derived the electron beam velocity as well as the height, ambient plasma temperature, and density at the level of formation of the 160 MHz emission. From the analysis of the differential emission measure derived from the AIA images, we found that the first evidence of energy release was at the footpoints, and this was followed by the development of flaring loops and subsequent cooling. Conclusions: Even small energy release events can accelerate enough electrons to give rise to powerful IP type III bursts. The proximity of the electron acceleration site to open magnetic field lines facilitates the escape of the electrons into the interplanetary space. The offset between the site of energy release and the metric type III location warrants further investigation. The movie is available in electronic form at http://www.aanda.org

  7. Receptosecretory nature of type III cells in the taste bud.

    PubMed

    Yoshie, Sumio

    2009-01-01

    Type III cells in taste buds form chemical synapses with intragemmal afferent nerve fibers and are characterized by the presence of membrane-bound vesicles in the cytoplasm. Although the vesicles differ in shape and size among species, they are primarily categorized into small clear (40 nm in diameter) and large dense-cored (90-200 nm) types. As such vesicles tend to be closely juxtaposed to the synaptic membrane of the cells, it is reasonable to consider that the vesicles include transmitter(s) towards the gustatory nerve. In the guinea-pig taste bud, stimulation with various taste substances (sucrose, sodium chloride, quinine hydrochloride, or monosodium L-glutamate) causes ultrastructural alterations of the type III cells. At the synapse, the presynaptic plasma membrane often displays invaginations of 90 nm in a mean diameter towards the cytoplasm, which indicates the dense-cored vesicles opening into the synaptic cleft by means of exocytosis. The vesicles are also exocytosed at the non-synaptic region into the intercellular space. These findings strongly suggest that the transmitters presumably contained in the vesicles are released to conduct the excitement of the type III cells to the nerves and also to exert their paracrine effects upon the surroundings, such as the Ebner's salivary gland, acting as local hormones. PMID:20224182

  8. TYPE III EXCITABILITY, SLOPE SENSITIVITY AND COINCIDENCE DETECTION

    PubMed Central

    Meng, Xiangying; Huguet, Gemma; Rinzel, John

    2013-01-01

    Some neurons in the nervous system do not show repetitive firing for steady currents. For time-varying inputs, they fire once if the input rise is fast enough. This property of phasic firing is known as Type III excitability. Type III excitability has been observed in neurons in the auditory brainstem (MSO), which show strong phase-locking and accurate coincidence detection. In this paper, we consider a Hodgkin-Huxley type model (RM03) that is widely-used for phasic MSO neurons and we compare it with a modification of it, showing tonic behavior. We provide insight into the temporal processing of these neuron models by means of developing and analyzing two reduced models that reproduce qualitatively the properties of the exemplar ones. The geometric and mathematical analysis of the reduced models allows us to detect and quantify relevant features for the temporal computation such as nearness to threshold and a temporal integration window. Our results underscore the importance of Type III excitability for precise coincidence detection. PMID:23667306

  9. Type II and Type III Radio Bursts and their Correlation with Solar Energetic Proton Events

    NASA Astrophysics Data System (ADS)

    Winter, L. M.; Ledbetter, K.

    2015-08-01

    Using the Wind/WAVES radio observations from 2010 to 2013, we present an analysis of the 123 decametric–hectometric (DH) type II solar radio bursts during this period, the associated type III burst properties, and their correlation with solar energetic proton (SEP) properties determined from analysis of the Geostationary Operational Environmental Satellite (GOES) observations. We present a useful catalog of the type II burst, type III burst, Langmuir wave, and proton flux properties for these 123 events, which we employ to develop a statistical relationship between the radio properties and peak proton flux that can be used to forecast SEP events. We find that all SEP events with a peak \\gt 10 MeV flux above 15 protons cm‑2 s‑1 sr‑1 are associated with a type II burst and virtually all SEP events, 92%, are also associated with a type III radio burst. Based on a principal component analysis, the radio burst properties that are most highly correlated with the occurrence of gradual SEP events and account for the most variance in the radio properties are the type III burst intensity and duration. Further, a logistic regression analysis with the radio-derived principal component (dominated by the type III and type II radio burst intensity and type III duration) obtains SEP predictions approaching the human forecaster rates, with a false alarm rate of 22%, a probability of detection of 62%, and with 85% of the classifications correct. Therefore, type III radio bursts that occur along with a DH type II burst are shown to be an important diagnostic that can be used to forecast SEP events.

  10. Type II and Type III Radio Bursts and their Correlation with Solar Energetic Proton Events

    NASA Astrophysics Data System (ADS)

    Winter, L. M.; Ledbetter, K.

    2015-08-01

    Using the Wind/WAVES radio observations from 2010 to 2013, we present an analysis of the 123 decametric-hectometric (DH) type II solar radio bursts during this period, the associated type III burst properties, and their correlation with solar energetic proton (SEP) properties determined from analysis of the Geostationary Operational Environmental Satellite (GOES) observations. We present a useful catalog of the type II burst, type III burst, Langmuir wave, and proton flux properties for these 123 events, which we employ to develop a statistical relationship between the radio properties and peak proton flux that can be used to forecast SEP events. We find that all SEP events with a peak \\gt 10 MeV flux above 15 protons cm-2 s-1 sr-1 are associated with a type II burst and virtually all SEP events, 92%, are also associated with a type III radio burst. Based on a principal component analysis, the radio burst properties that are most highly correlated with the occurrence of gradual SEP events and account for the most variance in the radio properties are the type III burst intensity and duration. Further, a logistic regression analysis with the radio-derived principal component (dominated by the type III and type II radio burst intensity and type III duration) obtains SEP predictions approaching the human forecaster rates, with a false alarm rate of 22%, a probability of detection of 62%, and with 85% of the classifications correct. Therefore, type III radio bursts that occur along with a DH type II burst are shown to be an important diagnostic that can be used to forecast SEP events.

  11. Identification of type II and type III pyoverdine receptors from Pseudomonas aeruginosa.

    PubMed

    de Chial, Magaly; Ghysels, Bart; Beatson, Scott A; Geoffroy, Valérie; Meyer, Jean Marie; Pattery, Theresa; Baysse, Christine; Chablain, Patrice; Parsons, Yasmin N; Winstanley, Craig; Cordwell, Stuart J; Cornelis, Pierre

    2003-04-01

    Pseudomonas aeruginosa produces, under conditions of iron limitation, a high-affinity siderophore, pyoverdine (PVD), which is recognized at the level of the outer membrane by a specific TonB-dependent receptor, FpvA. So far, for P. aeruginosa, three different PVDs, differing in their peptide chain, have been described (types I-III), but only the FpvA receptor for type I is known. Two PVD-producing P. aeruginosa strains, one type II and one type III, were mutagenized by a mini-TnphoA3 transposon. In each case, one mutant unable to grow in the presence of the strong iron chelator ethylenediaminedihydroxyphenylacetic acid (EDDHA) and the cognate PVD was selected. The first mutant, which had an insertion in the pvdE gene, upstream of fpvA, was unable to take up type II PVD and showed resistance to pyocin S3, which is known to use type II FpvA as receptor. The second mutant was unable to take up type III PVD and had the transposon insertion in fpvA. Cosmid libraries of the respective type II and type III PVD wild-type strains were constructed and screened for clones restoring the capacity to grow in the presence of PVD. From the respective complementing genomic fragments, type II and type III fpvA sequences were determined. When in trans, type II and type III fpvA restored PVD production, uptake, growth in the presence of EDDHA and, in the case of type II fpvA, pyocin S3 sensitivity. Complementation of fpvA mutants obtained by allelic exchange was achieved by the presence of cognate fpvA in trans. All three receptors posses an N-terminal extension of about 70 amino acids, similar to FecA of Escherichia coli, but only FpvAI has a TAT export sequence at its N-terminal end. PMID:12686625

  12. False lumens in type III aortic dissections: progress CT study

    SciTech Connect

    Yamaguchi, T.; Naito, H.; Ohta, M.; Sugahara, T.; Takamiya, M.; Kozuka, T.; Nakajima, N.

    1985-09-01

    The fate of false lumens in 13 patients having Type III aortic dissections was studied using computed tomography (CT). Contrast media filled false lumens with or without thrombosis were observed in ten patients; the false lumens of three patients were entirely thrombosed at initial examination. Follow-up CT studies showed shrinkage or disappearance of the false lumens with thrombosis in four patients, progression of thrombosis in two patients, and enlargement of the false lumen in one patient who subsequently required surgical repair. No change was observed in the remaining six patients during our observation period. CT study provides useful information for evaluating the efficacy of medical treatment and the timing of surgical intervention during follow-up evaluation of medically treated Type III aortic dissections.

  13. False lumens in type III aortic dissections: progress CT study.

    PubMed

    Yamaguchi, T; Naito, H; Ohta, M; Sugahara, T; Takamiya, M; Kozuka, T; Nakajima, N

    1985-09-01

    The fate of false lumens in 13 patients having Type III aortic dissections was studied using computed tomography (CT). Contrast media filled false lumens with or without thrombosis were observed in ten patients; the false lumens of three patients were entirely thrombosed at initial examination. Follow-up CT studies showed shrinkage or disappearance of the false lumens with thrombosis in four patients, progression of thrombosis in two patients, and enlargement of the false lumen in one patient who subsequently required surgical repair. No change was observed in the remaining six patients during our observation period. CT study provides useful information for evaluating the efficacy of medical treatment and the timing of surgical intervention during follow-up evaluation of medically treated Type III aortic dissections.

  14. Emission Patterns of Solar Type III Radio Bursts: Stereoscopic Observations

    NASA Technical Reports Server (NTRS)

    Thejappa, G.; MacDowall, R.; Bergamo, M.

    2012-01-01

    Simultaneous observations of solar type III radio bursts obtained by the STEREO A, B, and WIND spacecraft at low frequencies from different vantage points in the ecliptic plane are used to determine their directivity. The heliolongitudes of the sources of these bursts, estimated at different frequencies by assuming that they are located on the Parker spiral magnetic field lines emerging from the associated active regions into the spherically symmetric solar atmosphere, and the heliolongitudes of the spacecraft are used to estimate the viewing angle, which is the angle between the direction of the magnetic field at the source and the line connecting the source to the spacecraft. The normalized peak intensities at each spacecraft Rj = Ij /[Sigma]Ij (the subscript j corresponds to the spacecraft STEREO A, B, and WIND), which are defined as the directivity factors are determined using the time profiles of the type III bursts. It is shown that the distribution of the viewing angles divides the type III bursts into: (1) bursts emitting into a very narrow cone centered around the tangent to the magnetic field with angular width of approximately 2 deg and (2) bursts emitting into a wider cone with angular width spanning from [approx] -100 deg to approximately 100 deg. The plots of the directivity factors versus the viewing angles of the sources from all three spacecraft indicate that the type III emissions are very intense along the tangent to the spiral magnetic field lines at the source, and steadily fall as the viewing angles increase to higher values. The comparison of these emission patterns with the computed distributions of the ray trajectories indicate that the intense bursts visible in a narrow range of angles around the magnetic field directions probably are emitted in the fundamental mode, whereas the relatively weaker bursts visible to a wide range of angles are probably emitted in the harmonic mode.

  15. Assembly and function of type III secretory systems.

    PubMed

    Cornelis, G R; Van Gijsegem, F

    2000-01-01

    Type III secretion systems allow Yersinia spp., Salmonella spp., Shigella spp., Bordetella spp., and Pseudomonas aeruginosa and enteropathogenic Escherichia coli adhering at the surface of a eukaryotic cell to inject bacterial proteins across the two bacterial membranes and the eukaryotic cell membrane to destroy or subvert the target cell. These systems consist of a secretion apparatus, made of approximately 25 proteins, and an array of proteins released by this apparatus. Some of these released proteins are "effectors," which are delivered into the cytosol of the target cell, whereas the others are "translocators," which help the effectors to cross the membrane of the eukaryotic cell. Most of the effectors act on the cytoskeleton or on intracellular-signaling cascades. A protein injected by the enteropathogenic E. coli serves as a membrane receptor for the docking of the bacterium itself at the surface of the cell. Type III secretion systems also occur in plant pathogens where they are involved both in causing disease in susceptible hosts and in eliciting the so-called hypersensitive response in resistant or nonhost plants. They consist of 15-20 Hrp proteins building a secretion apparatus and two groups of effectors: harpins and avirulence proteins. Harpins are presumably secreted in the extracellular compartment, whereas avirulence proteins are thought to be targeted into plant cells. Although a coherent picture is clearly emerging, basic questions remain to be answered. In particular, little is known about how the type III apparatus fits together to deliver proteins in animal cells. It is even more mysterious for plant cells where a thick wall has to be crossed. In spite of these haunting questions, type III secretion appears as a fascinating trans-kingdom communication device. PMID:11018143

  16. What's the point of the type III secretion system needle?

    PubMed Central

    Blocker, Ariel J.; Deane, Janet E.; Veenendaal, Andreas K. J.; Roversi, Pietro; Hodgkinson, Julie L.; Johnson, Steven; Lea, Susan M.

    2008-01-01

    Recent work by several groups has significantly expanded our knowledge of the structure, regulation of assembly, and function of components of the extracellular portion of the type III secretion system (T3SS) of Gram-negative bacteria. This perspective presents a structure-informed analysis of functional data and discusses three nonmutually exclusive models of how a key aspect of T3SS biology, the sensing of host cells, may be performed. PMID:18458349

  17. X-ray Flares and their Type III Radio Signature

    NASA Astrophysics Data System (ADS)

    Vilmer, N.; Reid, H.

    2012-12-01

    Oppositely directed accelerated electron beams in solar flares can produce Hard X-rays in the chromosphere and radio emission from the low corona to the interplanetary medium. The temporal and inferred spectral correlation of these electron beams indicates a common acceleration region. We used the RHESSI X-ray flare catalogue and the PHOENIX catalogue of radio bursts to select a list of events with impulsive X-ray signatures that was correlated in time with type III radio emission in the decimetric range. We furthermore selected events for which the Nançay Radioheliograph had spatially resolved information in the 450-150 MHz range. We investigate the percentage of decimetric/metric type III radio bursts that have a counterpart at lower frequencies (14 - 1 MHz) observed with Wind/Waves. We will discuss the electron beam characteristics deduced from X-ray observations that affect the relationship between coronal and interplanetary type III bursts. Moreover, we will use the combined images in radio and X-ray frequencies to deduce the role of the local coronal environment.

  18. Murine gammaherpesvirus targets type I IFN receptor but not type III IFN receptor early in infection.

    PubMed

    Lopušná, Katarína; Benkóczka, Tímea; Lupták, Jakub; Matúšková, Radka; Lukáčiková, Ľubomíra; Ovečková, Ingrid; Režuchová, Ingeborg

    2016-07-01

    The innate immune response represents a primary line of defense against invading viral pathogens. Since epithelial cells are the primary site of gammaherpesvirus replication during infection in vivo and there are no information on activity of IFN-III signaling against gammaherpesviruses in this cell type, in present study, we evaluated the expression profile and virus-host interactions in mouse mammary epithelial cell (NMuMG) infected with three strains of murine gammaherpesvirus, MHV-68, MHV-72 and MHV-4556. Studying three strains of murine gammaherpesvirus, which differ in nucleotide sequence of some structural and non-structural genes, allowed us to compare the strain-dependent interactions with host organism. Our results clearly demonstrate that: (i) MHV-68, MHV-72 and MHV-4556 differentially interact with intracellular signaling and dysregulate IFN signal transduction; (ii) MHV-68, MHV-72 and MHV-4556 degrade type I IFN receptor in very early stages of infection (2-4hpi), but not type III IFN receptor; (iii) type III IFN signaling might play a key role in antiviral defense of epithelial cells in early stages of murine gammaherpesvirus replication; (iv) NMuMG cells are an appropriate model for study of not only type I IFN signaling, but also type III IFN signaling pathway. These findings are important for better understanding of individual virus-host interactions in lytic as well as in persistent gammaherpesvirus replication and help us to elucidate IFN-III function in early events of virus infection. PMID:27152708

  19. A qualitative study of recovery from type III-B and III-C tibial fractures.

    PubMed

    Shauver, Melissa S; Aravind, Maya S; Chung, Kevin C

    2011-01-01

    The literature has shown that long-term outcomes for both below-knee amputation and reconstruction after type III-B and III-C tibial fracture are poor. Yet, patients often report satisfaction with their treatment and outcomes. The aim of this study was to explore the relationship between patient outcomes and satisfaction after open tibial fractures via qualitative methodology. Twenty patients who were treated for open tibial fractures at one institution were selected using purposeful sampling and interviewed in-person in a semi-structured manner. Data were analyzed using grounded theory methodology. Despite reporting marked physical and psychosocial deficits, participants relayed high satisfaction. We hypothesize that the use of adaptive coping techniques successfully reduces stress, which leads to an increase in coping self-efficacy that results in the further use of adaptive coping strategies, culminating in personal growth. This stress reduction and personal growth leads to satisfaction despite poor functional and emotional outcomes.

  20. Insight into the flagella type III export revealed by the complex structure of the type III ATPase and its regulator.

    PubMed

    Imada, Katsumi; Minamino, Tohru; Uchida, Yumiko; Kinoshita, Miki; Namba, Keiichi

    2016-03-29

    FliI and FliJ form the FliI6FliJ ATPase complex of the bacterial flagellar export apparatus, a member of the type III secretion system. The FliI6FliJ complex is structurally similar to the α3β3γ complex of F1-ATPase. The FliH homodimer binds to FliI to connect the ATPase complex to the flagellar base, but the details are unknown. Here we report the structure of the homodimer of a C-terminal fragment of FliH (FliHC2) in complex with FliI. FliHC2 shows an unusually asymmetric homodimeric structure that markedly resembles the peripheral stalk of the A/V-type ATPases. The FliHC2-FliI hexamer model reveals that the C-terminal domains of the FliI ATPase face the cell membrane in a way similar to the F/A/V-type ATPases. We discuss the mechanism of flagellar ATPase complex formation and a common origin shared by the type III secretion system and the F/A/V-type ATPases. PMID:26984495

  1. A clinical study of canine collagen type III glomerulopathy

    PubMed Central

    2013-01-01

    Background Collagen type III glomerulopathy (Col3GP), also known as collagenofibrotic glomerulonephropathy, is a rare renal disease with unknown pathogenesis that occurs in animals and humans. We recently described a naturally occurring canine autosomal recessive model of Col3GP, and the aim of the present work was to study the clinical features of canine Col3GP and compare with the human phenotype. In humans two different clinical syndromes with different age at onset (child- or adulthood) have been observed. In children a more aggressive course with familial occurrence is described, characterized by progressively increasing proteinuria, nephrotic syndrome, hypertension and chronic renal failure. A markedly increased serum level of the aminoterminal propeptide of type III procollagen (PIIINP) is considered a useful marker for the disease. Since Col3GP and concurrent hypocomplementemia have been observed in humans, we also aimed to investigate if hypocomplementemia was present in Col3GP affected dogs. A litter consisting of seven puppies, four Col3GP affected and three healthy unaffected, was observed from the day of birth until the affected puppies developed a mild or moderate renal azotemia. Results During the period of observation growth retardation, increasing blood pressure, progressive proteinuria, azotemia, hypoalbuminemia, hypercholesterolemia and increased serum PIIINP were observed in all the affected dogs. Hypocomplementemia was not detected. Affected dogs were euthanized between 109 and 144 days of age, and pathological examinations revealed ascites and massive glomerular accumulations of collagen type III, consistent with Col3GP. Conclusions Dogs with Col3GP develop juvenile chronic renal failure, preceded by nephrotic syndrome, elevated serum PIIINP and hypertension, thus have similar clinical features as the juvenile Col3GP in humans. Further studies of this naturally occurring canine phenotype may provide more information on the pathogenesis and

  2. REGULATION OF THE ANTIBODY RESPONSE TO TYPE III PNEUMOCOCCAL POLYSACCHARIDE

    PubMed Central

    Baker, Phillip J.; Reed, Norman D.; Stashak, Philip W.; Amsbaugh, Diana F.; Prescott, Benjamin

    1973-01-01

    The effect of treatment with antilymphocyte serum (ALS) on the magnitude of the plaque-forming cell (PFC) response to Type III pneumococcal polysaccharide (SSS-III) was assessed in athymic nude mice and thymus-bearing littermate controls. Without ALS treatment, the PFC response was slightly higher in nude than in control mice. Treatment with ALS had no effect on the response of nude mice; however, considerable enhancement was noted in thymus-bearing controls. Such enhancement was ALS dose-dependent and demonstrable under conditions in which there was substantial inactivation of thymic-derived "helper" cells required for an antibody response to erythrocyte antigens. These findings suggest that amplifier and suppressor cells, which have been reported to regulate the magnitude of the antibody response to SSS-III, represent populations of thymic-derived cells (T cells) that are not present in nude mice. The activities of "helper" T cells and regulatory T cells appear to be independent of one another and mediated by separate subpopulations of T cells. PMID:4145387

  3. A theory of solar type III radio bursts

    NASA Technical Reports Server (NTRS)

    Goldstein, M. L.; Papadopoulos, K.; Smith, R. A.

    1979-01-01

    A theory of type III bursts is reviewed. Energetic electrons propagating through the interplanetary medium are shown to excite the one dimensional oscillating two stream instability (OTSI). The OTSI is in turn stabilized by anomalous resistivity which completes the transfer of long wavelength Langmuir waves to short wavelengths, out of resonance with the electrons. The theory explains the small energy losses suffered by the electrons in propagating to 1 AU, the predominance of second harmonic radiation, and the observed correlation between radio and electron fluxes.

  4. 77 FR 76426 - Payout Requirements for Type III Supporting Organizations That Are Not Functionally Integrated

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... affect Type III supporting organizations and their supported organizations. The text of those temporary...), which are known as supporting organizations. The final and temporary regulations provide requirements to... Type III supporting organizations and their supported organizations. The text of those...

  5. Radio frequency interference affecting type III solar burst observations

    NASA Astrophysics Data System (ADS)

    Anim, N. M.; Hamidi, Z. S.; Abidin, Z. Z.; Monstein, C.; Rohizat, N. S.

    2013-05-01

    The solar burst extinguish from the Sun's corona atmosphere and it dynamical structure of the magnetic field in radio wavelength are studied. Observation of solar radio burst with Compact Astronomical Low cost Low frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) from ETH, Zurich in frequency range of 45 until 870 MHz. Observation done at Pusat Angkasa Negara, Banting, Selangor and successfully detected the solar burst type III on 9th March 2012 from 4:22:00 UT until 4:28:00 UT. The solar burst emission is associated with M6.3 solar flare which occurred at sunspot AR1429 at 03:58UT were observed by NOAA. Frequency ranges chosen as the best ranges for solar monitoring in Malaysia is 150 MHz until 400 MHz. The highest signal amplitude within this frequency ranges is 1.7619 dB at 153.188 MHz (Government Use) have potential to influence the detection of solar radio burst type III within 20 until 400 MHz.

  6. Fundamental and harmonic radiation in type III solar radio bursts

    NASA Technical Reports Server (NTRS)

    Robinson, P. A.; Cairns, I. H.

    1994-01-01

    Type III solar radio bursts are investigated by modeling the propagation of the electron beam and the generation and subsequent propagation of waves to the observer. Predictions from this model are compared in detail with particle, Langmuir wave, and radio data from the International Sun Earth Explorer-3 (ISSE-3) spacecraft and with other observations to clarify the roles of fundamental and harmonic emission in type III radio bursts. Langmuir waves are seen only after the arrival of the beam, in accord with the standard theory. These waves persist after a positive beam slope is last resolved, implying that sporadic positive slopes persist for some time, unresolved but in accord with the predictions of stochastic growth theory. Local electromagnetic emission sets in only after Langmuir waves are seen, in accord with the standard theory, which relies on nonlinear processes involving Langmuir waves. In the events investigated here, fundamental radiation appears to dominate early in the event, followed and/or accompanied by harmonic radiation after the peak, with a long-lived tail of multiply scattered fundamental or harmonic emission extending long afterwards. These results are largely independent of, but generally consistent with, the conclusions of earlier works.

  7. Wave-wave interactions in solar type III radio bursts

    SciTech Connect

    Thejappa, G.; MacDowall, R. J.

    2014-02-11

    The high time resolution observations from the STEREO/WAVES experiment show that in type III radio bursts, the Langmuir waves often occur as localized magnetic field aligned coherent wave packets with durations of a few ms and with peak intensities well exceeding the strong turbulence thresholds. Some of these wave packets show spectral signatures of beam-resonant Langmuir waves, down- and up-shifted sidebands, and ion sound waves, with frequencies, wave numbers, and tricoherences satisfying the resonance conditions of the oscillating two stream instability (four wave interaction). The spectra of a few of these wave packets also contain peaks at f{sub pe}, 2f{sub pe} and 3 f{sub pe} (f{sub pe} is the electron plasma frequency), with frequencies, wave numbers and bicoherences (computed using the wavelet based bispectral analysis techniques) satisfying the resonance conditions of three wave interactions: (1) excitation of second harmonic electromagnetic waves as a result of coalescence of two oppositely propagating Langmuir waves, and (2) excitation of third harmonic electromagnetic waves as a result of coalescence of Langmuir waves with second harmonic electromagnetic waves. The implication of these findings is that the strong turbulence processes play major roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation in type III radio bursts.

  8. On the solar type III radio burst emission process

    NASA Astrophysics Data System (ADS)

    Wentzel, D. G.

    1982-05-01

    The application of a version of the nonlinear plasma theories involving plasma solitons to the corona is investigated. A fairly compact beam is assumed in order to initiate nonlinear plasma phenomena in the corona. The beam's survival is favored by open magnetic fields, and the solitons occur in a front about 1 km thick. The fundamental is emitted at this front and depends strongly on the beam energy through its dependence on the narrow angle of emission. The variability of the fundamental indicates the beam evolution at the beam's front. Observations addressed by the theory include correlations of type III bursts with coronal structure and temperature, the emission of fundamental and harmonic from different source volumes, the polarization of the fundamental, and the starting and disappearance of bursts in the corona, especially type IIIb bursts.

  9. Hereditary sensory and autonomic neuropathies: types II, III, and IV.

    PubMed

    Axelrod, Felicia B; Gold-von Simson, Gabrielle

    2007-01-01

    The hereditary sensory and autonomic neuropathies (HSAN) encompass a number of inherited disorders that are associated with sensory dysfunction (depressed reflexes, altered pain and temperature perception) and varying degrees of autonomic dysfunction (gastroesophageal reflux, postural hypotention, excessive sweating). Subsequent to the numerical classification of four distinct forms of HSAN that was proposed by Dyck and Ohta, additional entities continue to be described, so that identification and classification are ongoing. As a group, the HSAN are rare diseases that affect both sexes. HSAN III is almost exclusive to individuals of Eastern European Jewish extraction, with incidence of 1 per 3600 live births. Several hundred cases with HSAN IV have been reported. The worldwide prevalence of HSAN type II is very low. This review focuses on the description of three of the disorders, HSAN II through IV, that are characterized by autosomal recessive inheritance and onset at birth. These three forms of HSAN have been the most intensively studied, especially familial dysautonomia (Riley-Day syndrome or HSAN III), which is often used as a prototype for comparison to the other HSAN. Each HSAN disorder is likely caused by different genetic errors that affect specific aspects of small fiber neurodevelopment, which result in variable phenotypic expression. As genetic tests are routinely used for diagnostic confirmation of HSAN III only, other means of differentiating between the disorders is necessary. Diagnosis is based on the clinical features, the degree of both sensory and autonomic dysfunction, and biochemical evaluations, with pathologic examinations serving to further confirm differences. Treatments for all these disorders are supportive. PMID:17915006

  10. The spectrum of type III lissencephaly: a clinicopathological update.

    PubMed

    Allias, Fabienne; Buenerd, Annie; Bouvier, Raymonde; Attia-Sobol, Jocelyne; Dijoud, Frédérique; Clémenson, Alixe; Encha-Razavi, Férechté

    2004-01-01

    A third type of lissencephaly that does not fufil diagnostic criteria of type I ("classical") and type II ("cobblestone") lissencephaly was described by our group as a new entity identified as OMIM 601160. This lethal familial syndrome comprises micrencephaly/lissencephaly and a spectrum of abnormalities lined to a severe fetal akinesia deformation sequence. Neuropathological findings suggest severe neurodegeneration leading to a marked neuronal dropout of the entire central nervous system and atrophy. Similar neuropathological findings have been described in the Neu-Laxova syndrome (NLS), an apparently different lethal malformation syndrome. Neuropathological similarities between OMIM 601160 and NLS raise the question of clinicopathological variability and genetic heterogeneity of type III lissencephaly. To answer this question, we compared our clinicopathological findings in a series of fetuses with OMIM 601160 to pathological data reported in NLS. In the study, 5 unrelated families with 7 affected fetuses were included. Interestingly, we found striking clinicopathological similarities between OMIM 601160 and NLS, which may represent a variability of a single neurodegenerative disease with early prenatal onset. Molecular studies in multiplex families defined through detailed clinicopathological screening are needed to clarify the distinction, if any, between these two entities. PMID:16137167

  11. Inhibition of Type III Interferon Activity by Orthopoxvirus Immunomodulatory Proteins

    PubMed Central

    2010-01-01

    The type III interferon (IFN) family elicits an antiviral response that is nearly identical to that evoked by IFN-α/β. However, these cytokines (known as IFN-λ1, 2, and 3) signal through a distinct receptor, and thus may be resistant to the evasion strategies used by some viruses to avoid the IFN-α/β response. Orthopoxviruses are highly resistant to IFN-α/β because they encode well-characterized immunomodulatory proteins that inhibit IFN activity. These include a secreted receptor (B18R) that neutralizes IFN-α/β, and a cytoplasmic protein (E3L) that blocks IFN-α/β effector functions in infected cells. We therefore determined the ability of these immunomodulators to abrogate the IFN-λ–induced antiviral response. We found that (i) vaccinia virus (VACV) replication is resistant to IFN-λ antiviral activity; (ii) neither VACV B18R nor the variola virus homolog B20R neutralizes IFN-λ; (iii) VACV E3L inhibits the IFN-λ–mediated antiviral response through a PKR-dependent pathway; (iv) VACV infection inhibits IFN-λR–mediated signal transduction and gene expression. These results demonstrate differential sensitivity of IFN-λ to multiple distinct evasion mechanisms employed by a single virus. PMID:20038204

  12. Clark Lake microbursts - On a lower limit to type III burst brightness temperatures

    NASA Technical Reports Server (NTRS)

    White, S. M.; Kundu, M. R.; Szabo, A.

    1987-01-01

    Further observations of solar microbursts by the Clark Lake radioheliograph are reported. The microbursts have properties consistent with weak type III bursts, with the implication that type III's can have brightness temperatures as low as 1 million K. The importance of this result is explored. A single model to explain the stronger type III bursts and the weaker microbursts is sought. It is shown that none of the models for stabilizing the strongest type III electron streams can explain the observed microbursts: these models have threshold levels of Langmuir waves which imply emission (due to spontaneous scattering off ions) with brightness temperatures in excess of those observed. It appears that either some vital physics is still missing from models for type III bursts, or that microbursts should have properties significantly different from those of type III bursts. In the latter case further observations should allow important tests of type III models.

  13. Kinetic Differences and Synergistic Antiviral Effects Between Type I and Type III Interferon Signaling Indicate Pathway Independence

    PubMed Central

    Voigt, Emily A.

    2015-01-01

    The spread of acute respiratory viral infections is controlled by type I and III interferon (IFN) signaling. While the mechanisms of type I IFN signaling have been studied in detail, features that distinguish type III IFN signaling remain poorly understood. Type III IFNs play an essential role in limiting infections of intestinal and respiratory epithelial surfaces; however, type III IFNs have been shown to activate similar genes to type I IFNs, raising the question of how these IFNs differ and their signals interact. We measured the kinetics of type I and III IFN activation, functional stability, and downstream antiviral responses on A549 human lung epithelial cells. Similar kinetics were found for transcriptional upregulation and secretion of type I and III IFNs in response to infection by an RNA virus, peaking at 12 h postinfection, and both protein types had similar stabilities with functional half-lives extending beyond 2 days. Both IFNs activated potent cellular antiviral responses; however, responses to type III IFNs were delayed by 2–6 h relative to type I IFN responses. Combined treatments with type I and III IFNs produced enhanced antiviral effects, and quantitative analysis of these data with a Bliss interaction model provides evidence for independence of type I and III IFN downstream signaling pathways. This novel synergistic interaction has therapeutic implications for treatment of respiratory virus infections. PMID:25938799

  14. Noncanonical Effects of IRF9 in Intestinal Inflammation: More than Type I and Type III Interferons.

    PubMed

    Rauch, Isabella; Rosebrock, Felix; Hainzl, Eva; Heider, Susanne; Majoros, Andrea; Wienerroither, Sebastian; Strobl, Birgit; Stockinger, Silvia; Kenner, Lukas; Müller, Mathias; Decker, Thomas

    2015-07-01

    The interferon (IFN)-stimulated gene factor 3 (ISGF3) transcription factor with its Stat1, Stat2, and interferon regulatory factor 9 (IRF9) subunits is employed for transcriptional responses downstream of receptors for type I interferons (IFN-I) that include IFN-α and IFN-β and type III interferons (IFN-III), also called IFN-λ. Here, we show in a murine model of dextran sodium sulfate (DSS)-induced colitis that IRF9 deficiency protects animals, whereas the combined loss of IFN-I and IFN-III receptors worsens their condition. We explain the different phenotypes by demonstrating a function of IRF9 in a noncanonical transcriptional complex with Stat1, apart from IFN-I and IFN-III signaling. Together, Stat1 and IRF9 produce a proinflammatory activity that overrides the benefits of the IFN-III response on intestinal epithelial cells. Our results further suggest that the CXCL10 chemokine gene is an important mediator of this proinflammatory activity. We thus establish IFN-λ as a potentially anticolitogenic cytokine and propose an important role for IRF9 as a component of noncanonical Stat complexes in the development of colitis.

  15. Noncanonical Effects of IRF9 in Intestinal Inflammation: More than Type I and Type III Interferons

    PubMed Central

    Rauch, Isabella; Rosebrock, Felix; Hainzl, Eva; Heider, Susanne; Majoros, Andrea; Wienerroither, Sebastian; Strobl, Birgit; Stockinger, Silvia; Kenner, Lukas; Müller, Mathias

    2015-01-01

    The interferon (IFN)-stimulated gene factor 3 (ISGF3) transcription factor with its Stat1, Stat2, and interferon regulatory factor 9 (IRF9) subunits is employed for transcriptional responses downstream of receptors for type I interferons (IFN-I) that include IFN-α and IFN-β and type III interferons (IFN-III), also called IFN-λ. Here, we show in a murine model of dextran sodium sulfate (DSS)-induced colitis that IRF9 deficiency protects animals, whereas the combined loss of IFN-I and IFN-III receptors worsens their condition. We explain the different phenotypes by demonstrating a function of IRF9 in a noncanonical transcriptional complex with Stat1, apart from IFN-I and IFN-III signaling. Together, Stat1 and IRF9 produce a proinflammatory activity that overrides the benefits of the IFN-III response on intestinal epithelial cells. Our results further suggest that the CXCL10 chemokine gene is an important mediator of this proinflammatory activity. We thus establish IFN-λ as a potentially anticolitogenic cytokine and propose an important role for IRF9 as a component of noncanonical Stat complexes in the development of colitis. PMID:25918247

  16. Microstructures in type III events in the solar wind

    NASA Technical Reports Server (NTRS)

    Melrose, D. B.; Goldman, M. V.

    1987-01-01

    A model is presented for the generation and evolution of bump-in-tail driven Langmuir waves in the solar wind during type III emission which removes a number of apparent inconsistencies between theory and observations. Growth rates and energy densities of Langmuir waves are considerably enhanced, permitting growth to overcome linear scattering losses, and also allowing nonlinear decay into ion-acoustic waves, in line with observations. Estimates are made of the probability distribution p(E), of wave field strengths E, based on linear and nonlinear wave-packet evolution, yielding p(E) approximately equal to E exp -alpha, alpha greater than or equal to 3. This helps explain why very high values of E are rarely found in the measured spiky wave turbulence.

  17. Yersinia Type III Secretion System Master Regulator LcrF

    PubMed Central

    Schwiesow, Leah; Lam, Hanh

    2015-01-01

    Many Gram-negative pathogens express a type III secretion (T3SS) system to enable growth and survival within a host. The three human-pathogenic Yersinia species, Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica, encode the Ysc T3SS, whose expression is controlled by an AraC-like master regulator called LcrF. In this review, we discuss LcrF structure and function as well as the environmental cues and pathways known to regulate LcrF expression. Similarities and differences in binding motifs and modes of action between LcrF and the Pseudomonas aeruginosa homolog ExsA are summarized. In addition, we present a new bioinformatics analysis that identifies putative LcrF binding sites within Yersinia target gene promoters. PMID:26644429

  18. Directivity of low frequency solar type III radio bursts

    NASA Technical Reports Server (NTRS)

    Fitzenreiter, R. J.; Fainberg, J.; Bundy, R. B.

    1976-01-01

    The occurrence rate of type III solar bursts in the frequency range 4.9 MHz to 30 kHz is analyzed as a function of burst intensity and burst arrival direction. We find that (1) the occurrence rate of bursts varies inversely with the 1.5 power of the flux, and (2) the distribution of burst arrival directions at each frequency shows a significantly larger number of bursts observed west of the earth-sun line than east of it. This western excess in occurrence rate appears to be correlated with the direction of the average interplanetary magnetic field, and is interpreted as beaming of the observed burst radiation along the magnetic field direction.

  19. Nonlinear stability of solar type III radio bursts. I - Theory

    NASA Technical Reports Server (NTRS)

    Smith, R. A.; Goldstein, M. L.; Papadopoulos, K.

    1979-01-01

    A theory of the excitation of solar type III bursts is presented. Electrons initially unstable to the linear bump-in-tail instability are shown to rapidly amplify Langmuir waves to energy densities characteristic of strong turbulence. The three-dimensional equations which describe the strong coupling (wave-wave) interactions are derived. For parameters characteristic of the interplanetary medium the equations reduce to one-dimension. In that case the oscillating two-stream instability (OTSI) is the dominant nonlinear instability. OTSI is stabilized through the production of nonlinear ion density fluctuations that efficiently scatter Langmuir waves out of resonance with the electron beam. An analytical model of the electron distribution function is also developed which is used to estimate the total energy losses suffered by the electron beam as it propagates from the solar corona to 1 AU and beyond.

  20. High-Frequency Cutoff in Type III Bursts

    NASA Astrophysics Data System (ADS)

    Stanislavsky, A. A.; Konovalenko, A. A.; Volvach, Ya. S.; Koval, A. A.

    In this article we report about a group of solar bursts with high-frequency cutoff, observed on 19 August of 2012 near 8:23 UT, simultaneously by three different radio telescopes: the Ukrainian decameter radio telescope (8-33 MHz), the French Nancay Decametric Array (10-70 MHz) and the Italian San Vito Solar Observatory of RSTN (25-180 MHz). Morphologically the bursts are very similar to the type III bursts. The solar activity is connected with the emergency of a new group of solar spots on the far side of the Sun with respect to observers on Earth. The solar bursts accompany many moderate flares over eastern limb. The refraction of the behind-limb radio bursts towards the Earth is favorable, if CMEs generate low-density cavities in solar corona.

  1. Type III Secretion: Building and Operating a Remarkable Nanomachine.

    PubMed

    Portaliou, Athina G; Tsolis, Konstantinos C; Loos, Maria S; Zorzini, Valentina; Economou, Anastassios

    2016-02-01

    The Type III secretion system (T3SS) is a protein export pathway that is widespread in Gram-negative bacteria and delivers effector proteins directly into eukaryotic cells. At its core lie the injectisome (a sophisticated transmembrane secretion apparatus) and a complex network of specialized chaperones that target secretory proteins to the antechamber of the injectisome. The assembly of the system, and the subsequent secretion of proteins through it, undergo fine-tuned, hierarchical regulation. Here, we present the current understanding of the injectisome assembly process, secretion hierarchy, and the role of chaperones. We discuss these events in light of available structural and biochemical dissection and propose future directions essential to revealing mechanistic insight into this fascinating nanomachine. PMID:26520801

  2. Type III secretion systems: the bacterial flagellum and the injectisome

    PubMed Central

    Diepold, Andreas; Armitage, Judith P.

    2015-01-01

    The flagellum and the injectisome are two of the most complex and fascinating bacterial nanomachines. At their core, they share a type III secretion system (T3SS), a transmembrane export complex that forms the extracellular appendages, the flagellar filament and the injectisome needle. Recent advances, combining structural biology, cryo-electron tomography, molecular genetics, in vivo imaging, bioinformatics and biophysics, have greatly increased our understanding of the T3SS, especially the structure of its transmembrane and cytosolic components, the transcriptional, post-transcriptional and functional regulation and the remarkable adaptivity of the system. This review aims to integrate these new findings into our current knowledge of the evolution, function, regulation and dynamics of the T3SS, and to highlight commonalities and differences between the two systems, as well as their potential applications. PMID:26370933

  3. Radiative type III seesaw model and its collider phenomenology

    NASA Astrophysics Data System (ADS)

    von der Pahlen, Federico; Palacio, Guillermo; Restrepo, Diego; Zapata, Oscar

    2016-08-01

    We analyze the present bounds of a scotogenic model, the radiative type III seesaw, in which an additional scalar doublet and at least two fermion triplets of S U (2 )L are added to the Standard Model. In the radiative type III seesaw, the new physics (NP) sector is odd under an exact global Z2 symmetry. This symmetry guaranties that the lightest NP neutral particle is stable, providing a natural dark matter candidate, and leads to naturally suppressed neutrino masses generated by a one-loop realization of an effective Weinberg operator. We focus on the region with the highest sensitivity in present and future LHC searches, with light scalar dark matter and at least one NP fermion triplet at the sub-TeV scale. This region allows for significant production cross sections of NP fermion pairs at the LHC. We reinterpret a set of searches for supersymmetric particles at the LHC obtained using the package CheckMATE, to set limits on our model as a function of the masses of the NP particles and their Yukawa interactions. The most sensitive search channel is found to be dileptons plus missing transverse energy. In order to target the case of tau enhanced decays and the case of compressed spectra, we reinterpret the recent slepton and chargino search bounds by ATLAS. For a lightest NP fermion triplet with a maximal branching ratio to either electrons or muons, we exclude NP fermion masses of up to 650 GeV, while this bound is reduced to approximately 400 GeV in the tau-philic case. Allowing for a general flavor structure, we set limits on the Yukawa couplings, which are directly related to the neutrino flavor structure.

  4. Near-Relativistic Solar Electrons and Type III Radio Bursts

    NASA Technical Reports Server (NTRS)

    Cane, H. V.

    2003-01-01

    Recently it has been found that the inferred injection times of greater than 25 keV electrons are up to 30 minutes later than the start times of the associated type III radio bursts at the Sun. Thus it has been suggested that the electrons that produce type III bursts do not belong to the same population as those observed above 25 keV. This paper examines the characteristics and circumstances of 79 solar electron beam events measured on the ACE spacecraft. Particular attention is paid to the very low frequency emissions of the associated radio bursts and the ambient conditions at the arrival times of the electrons at the spacecraft. It is found that the inferred greater than 25 keV electron injection delays are correlated with the times required for the associated radio bursts to drift to the lowest frequencies. This suggests that the electrons responsible for the radio emission and those observed above 25 keV are part of a single population, and that the electrons both above and below 25 keV are delayed in the interplanetary medium. Further evidence for a single population is the general correspondence between electron and local radio intensities and temporal profiles. It is found that the delays increase with the ambient solar wind density consistent with the propagation times of the electrons being determined by the characteristics of the interplanetary medium. However it is known that particle arrival times at 1 AU are a linear function of inverse particle speed. Conventionally such a relationship is taken to indicate scatter-free propagation when inferred path lengths lie close to 1.2 AU, as they do for the electron events studied here. These conflicting interpretations require further investigation.

  5. Response of a Type III waste tank to hydrogen deflagration

    SciTech Connect

    Gong, Chung; Jerrell, J.W.; Pelfrey, J.R.; Yau, W.W.F.

    1992-05-01

    The type III waste tank is built with ASTM A516 Grade 70 steel shells in the shape of a torus with a central concrete core. The tank is buried underground and covered with a four foot thick reinforced concrete slab. The tank is enriched by 2.5 foot thick reinforced concrete wall. Between the tank surface and the wall there is a 2.5 foot annular space. The tank itself is called the ``primary liner.`` The interior surface of the concrete wall is line with steel plates, called the ``secondary liner.`` The base of the tank rests on a concrete mat. Underneath the mat the secondary liner extends from the wall to the central column surfaces. The bottom liner is attached to the reinforced concrete foundation. Based on the conditions that the tank is filled with liquid wastes to 50% of the design capacity, and that the accumulation of hydrogen becomes 20% inside its free board, the resulting deflagration would cause an overpressure of 100 psig in the tank [Wallace and Yau, 1986]. The task of this analysis is to simulate the ``hydrogen deflagration`` scenario in the Type III Waste Tank complex. During the deflagration, the stresses in the steel tank would be expected to exceed the elastic limit of the steel and the tank would then undergo large deformation. The concrete roof slab could be fractured by the expansion of the tank. The central concrete column would start to exhibit large deformation first. All the structural members in the system are expected to interact drastically during the deflagration.

  6. Response of a Type III waste tank to hydrogen deflagration

    SciTech Connect

    Gong, Chung; Jerrell, J.W.; Pelfrey, J.R.; Yau, W.W.F.

    1992-01-01

    The type III waste tank is built with ASTM A516 Grade 70 steel shells in the shape of a torus with a central concrete core. The tank is buried underground and covered with a four foot thick reinforced concrete slab. The tank is enriched by 2.5 foot thick reinforced concrete wall. Between the tank surface and the wall there is a 2.5 foot annular space. The tank itself is called the primary liner.'' The interior surface of the concrete wall is line with steel plates, called the secondary liner.'' The base of the tank rests on a concrete mat. Underneath the mat the secondary liner extends from the wall to the central column surfaces. The bottom liner is attached to the reinforced concrete foundation. Based on the conditions that the tank is filled with liquid wastes to 50% of the design capacity, and that the accumulation of hydrogen becomes 20% inside its free board, the resulting deflagration would cause an overpressure of 100 psig in the tank (Wallace and Yau, 1986). The task of this analysis is to simulate the hydrogen deflagration'' scenario in the Type III Waste Tank complex. During the deflagration, the stresses in the steel tank would be expected to exceed the elastic limit of the steel and the tank would then undergo large deformation. The concrete roof slab could be fractured by the expansion of the tank. The central concrete column would start to exhibit large deformation first. All the structural members in the system are expected to interact drastically during the deflagration.

  7. Mutations in DHDPSL are responsible for primary hyperoxaluria type III.

    PubMed

    Belostotsky, Ruth; Seboun, Eric; Idelson, Gregory H; Milliner, Dawn S; Becker-Cohen, Rachel; Rinat, Choni; Monico, Carla G; Feinstein, Sofia; Ben-Shalom, Efrat; Magen, Daniella; Weissman, Irith; Charon, Celine; Frishberg, Yaacov

    2010-09-10

    Primary hyperoxaluria (PH) is an autosomal-recessive disorder of endogenous oxalate synthesis characterized by accumulation of calcium oxalate primarily in the kidney. Deficiencies of alanine-glyoxylate aminotransferase (AGT) or glyoxylate reductase (GRHPR) are the two known causes of the disease (PH I and II, respectively). To determine the etiology of an as yet uncharacterized type of PH, we selected a cohort of 15 non-PH I/PH II patients from eight unrelated families with calcium oxalate nephrolithiasis for high-density SNP microarray analysis. We determined that mutations in an uncharacterized gene, DHDPSL, on chromosome 10 cause a third type of PH (PH III). To overcome the difficulties in data analysis attributed to a state of compound heterozygosity, we developed a strategy of "heterozygosity mapping"-a search for long heterozygous patterns unique to all patients in a given family and overlapping between families, followed by reconstruction of haplotypes. This approach enabled us to determine an allelic fragment shared by all patients of Ashkenazi Jewish descent and bearing a 3 bp deletion in DHDPSL. Overall, six mutations were detected: four missense mutations, one in-frame deletion, and one splice-site mutation. Our assumption is that DHDPSL is the gene encoding 4-hydroxy-2-oxoglutarate aldolase, catalyzing the final step in the metabolic pathway of hydroxyproline.

  8. Loss of PCLO function underlies pontocerebellar hypoplasia type III

    PubMed Central

    Ahmed, Mustafa Y.; Chioza, Barry A.; Rajab, Anna; Schmitz-Abe, Klaus; Al-Khayat, Aisha; Al-Turki, Saeed; Baple, Emma L.; Patton, Michael A.; Al-Memar, Ali Y.; Hurles, Matthew E.; Partlow, Jennifer N.; Hill, R. Sean; Evrony, Gilad D.; Servattalab, Sarah; Markianos, Kyriacos; Walsh, Christopher A.; Crosby, Andrew H.

    2015-01-01

    Objective: To identify the genetic cause of pontocerebellar hypoplasia type III (PCH3). Methods: We studied the original reported pedigree of PCH3 and performed genetic analysis including genome-wide single nucleotide polymorphism genotyping, linkage analysis, whole-exome sequencing, and Sanger sequencing. Human fetal brain RNA sequencing data were then analyzed for the identified candidate gene. Results: The affected individuals presented with severe global developmental delay and seizures starting in the first year of life. Brain MRI of an affected individual showed diffuse atrophy of the cerebrum, cerebellum, and brainstem. Genome-wide single nucleotide polymorphism analysis confirmed the linkage to chromosome 7q we previously reported, and showed no other genomic areas of linkage. Whole-exome sequencing of 2 affected individuals identified a shared homozygous, nonsense variant in the PCLO (piccolo) gene. This variant segregated with the disease phenotype in the pedigree was rare in the population and was predicted to eliminate the PDZ and C2 domains in the C-terminus of the protein. RNA sequencing data of human fetal brain showed that PCLO was moderately expressed in the developing cerebral cortex. Conclusions: Here, we show that a homozygous, nonsense PCLO mutation underlies the autosomal recessive neurodegenerative disorder, PCH3. PCLO is a component of the presynaptic cytoskeletal matrix, and is thought to be involved in regulation of presynaptic proteins and synaptic vesicles. Our findings suggest that PCLO is crucial for the development and survival of a wide range of neuronal types in the human brain. PMID:25832664

  9. Development of a recombinant human collagen-type III based hemostat.

    PubMed

    Yang, C; Hillas, P; Tang, J; Balan, J; Notbohm, H; Polarek, J

    2004-04-15

    Animal-tissue-derived collagen, containing mostly type I collagen with a minor amount of type III collagen, has been widely used in the production of hemostats for many decades, although it has been known for a long time that type III collagen is more likely to induce platelet aggregation in vitro. Because it is hard to purify type III from animal tissue, it has not been possible to correlate this finding with in vivo data. In this report, it is demonstrated that recombinant human collagen III fibrils are more capable of inducing platelet aggregation in vitro than those comprised of bovine collagen I, in agreement with previously published data on tissue-derived type III collagen. When formed into three-dimensional matrices, the use of type III collagen results in formulations with better mechanical integrity, larger surface area, and higher hemostatic activity in a rabbit spleen injury model as compared with commercially available hemostats formed from bovine type I collagen.

  10. Adsorptive separation of rhodium(III) using Fe(III)-templated oxine type of chemically modified chitosan

    SciTech Connect

    Alam, M.S.; Inoue, Katsutoshi; Yoshizuka, Kazuharu; Ishibashi, Hideaki

    1998-03-01

    The oxine type of chemically modified chitosan was prepared by the template crosslinking method using Fe(III) as a template ion. Batchwise adsorption of rhodium(III) on this chemically modified chitosan was examined from chloride media in the absence and presence of a large amount of tin(II). It was observed that the Fe(III)-templated oxine type of chemically modified chitosan shows better performance for rhodium adsorption than that of the original chitosan. When Sn(II) is absent from the solution, Rh(III) is hardly adsorbed on the modified chitosan and the order of selectivity of the adsorption of Rh(III), Pt(IV), and Cu(II) was found to be Pt(IV) > Cu(II) {approx} Rh(III). On the other hand, adsorption of rhodium is significantly increased in the presence of Sn(II) and the selectivity order of the adsorption was drastically changed to Rh(III) > Pt(IV) {much_gt} Cu(II), which ensures selective separation of Rh(III) from their mixture. Adsorption of Rh(III) increases with an increase in the concentration of Sn(II) in the aqueous solution, and maximum adsorption is achieved at a molar ratio, [Sn]/[Rh], of >6. The adsorption of Rh(III) decreases at a high concentration of hydrochloric acid. The maximum adsorption capacity was evaluated to be 0.92 mol/kg-dry adsorbent. Stripping tests of rhodium from the loaded chemically modified chitosan were carried out using different kinds of stripping agents containing some oxidizing agent. The maximum stripping of rhodium under these experimental conditions was found to be 72.5% by a single contact with 0.5 M HCl + 8 M HNO{sub 3}.

  11. Structure and Biophysics of Type III Secretion in Bacteria

    PubMed Central

    Chatterjee, Srirupa; Chaudhury, Sukanya; McShan, Andrew C.; Kaur, Kawaljit; De Guzman, Roberto N.

    2013-01-01

    Many plant and animal bacterial pathogens assemble a needle-like nanomachine, the type III secretion system (T3SS), to inject virulence proteins directly into eukaryotic cells to initiate infection. The ability of bacteria to inject effectors into host cells is essential for infection, survival, and pathogenesis for many Gram-negative bacteria, including Salmonella, Escherichia, Shigella, Yersinia, Pseudomonas, and Chlamydia spp. These pathogens are responsible for a wide variety of diseases, such as typhoid fever, large-scale food-borne illnesses, dysentery, bubonic plague, secondary hospital infections, and sexually transmitted diseases. The T3SS consists of structural and nonstructural proteins. The structural proteins assemble the needle apparatus, which consists of a membrane-embedded basal structure, an external needle that protrudes from the bacterial surface, and a tip complex that caps the needle. Upon host cell contact, a translocon is assembled between the needle tip complex and the host cell, serving as a gateway for translocation of effector proteins by creating a pore in the host cell membrane. Following delivery into the host cytoplasm, effectors initiate and maintain infection by manipulating host cell biology, such as cell signaling, secretory trafficking, cytoskeletal dynamics, and the inflammatory response. Finally, chaperones serve as regulators of secretion by sequestering effectors and some structural proteins within the bacterial cytoplasm. This review will focus on the latest developments and future challenges concerning the structure and biophysics of the needle apparatus. PMID:23521714

  12. GOES Type III Loop Heat Pipe Life Test Results

    NASA Technical Reports Server (NTRS)

    Ottenstein, Laura

    2011-01-01

    The GOES Type III Loop Heat Pipe (LHP) was built as a life test unit for the loop heat pipes on the GOES N-Q series satellites. This propylene LHP was built by Dynatherm Corporation in 2000 and tested continuously for approximately 14 months. It was then put into storage for 3 years. Following the storage period, the LHP was tested at Swales Aerospace to verify that the loop performance hadn t changed. Most test results were consistent with earlier results. At the conclusion of testing at Swales, the LHP was transferred to NASA/GSFC for continued periodic testing. The LHP has been set up for testing in the Thermal Lab at GSFC since 2006. A group of tests consisting of start-ups, power cycles, and a heat transport limit test have been performed every six to nine months since March 2006. Tests results have shown no change in the loop performance over the five years of testing. This presentation will discuss the test hardware, test set-up, and tests performed. Test results to be presented include sample plots from individual tests, along with conductance measurements for all tests performed.

  13. The Type III Secretion Translocation Pore Senses Host Cell Contact

    PubMed Central

    Armentrout, Erin I.; Rietsch, Arne

    2016-01-01

    Type III secretion systems (T3SS) are nano-syringes used by a wide range of Gram-negative pathogens to promote infection by directly injecting effector proteins into targeted host cells. Translocation of effectors is triggered by host-cell contact and requires assembly of a pore in the host-cell plasma membrane, which consists of two translocator proteins. Our understanding of the translocation pore, how it is assembled in the host cell membrane and its precise role in effector translocation, is extremely limited. Here we use a genetic technique to identify protein-protein contacts between pore-forming translocator proteins, as well as the T3SS needle-tip, that are critical for translocon function. The data help establish the orientation of the translocator proteins in the host cell membrane. Analysis of translocon function in mutants that break these contacts demonstrates that an interaction between the pore-forming translocator PopD and the needle-tip is required for sensing host cell contact. Moreover, tethering PopD at a dimer interface also specifically prevents host-cell sensing, arguing that the translocation pore is actively involved in detecting host cell contact. The work presented here therefore establishes a signal transduction pathway for sensing host cell contact that is initiated by a conformational change in the translocation pore, and is subsequently transmitted to the base of the apparatus via a specific contact between the pore and the T3SS needle-tip. PMID:27022930

  14. Solar Flares, Type III Radio Bursts, CMEs, and Energetic Particles

    NASA Technical Reports Server (NTRS)

    Cane, H. V.

    2004-01-01

    Despite the fact that it has been well known since the earliest observations that solar energetic particle events are well associated with solar flares it is often considered that the association is not physically significant. Instead, in large events, the particles are considered to be only accelerated at a shock driven by the coronal mass ejection (CME) that is also always present. If particles are accelerated in the associated flare, it is claimed that such particles do not find access to open field lines and therefore do not escape from the low corona. However recent work has established that long lasting type III radio bursts extending to low frequencies are associated with all prompt solar particle events. Such bursts establish the presence of open field lines. Furthermore, tracing the radio bursts to the lowest frequencies, generated near the observer, shows that the radio producing electrons gain access to a region of large angular extent. It is likely that the electrons undergo cross field transport and it seems reasonable that ions do also. Such observations indicate that particle propagation in the inner heliosphere is not yet fully understood. They also imply that the contribution of flare particles in major particle events needs to be properly addressed.

  15. Interplanetary baseline observations of type III solar radio bursts

    NASA Technical Reports Server (NTRS)

    Weber, R. R.; Fitzenreiter, R. J.; Novaco, J. C.; Fainberg, J.

    1977-01-01

    Simultaneous observations of type III radio bursts from spacecraft separated by 0.43 AU have been made using the solar orbiters Helios-A and Helios-B. The burst beginning at 19:22 UT on March 28, 1976, has been located from the intersection of the source directions measured at each spacecraft and from burst arrival-time differences. The source positions range from 0.03 AU from the sun at 3000 kHz to 0.08 AU at 585 kHz. The electron density along the burst trajectory and the exciter velocity (0.13c) were determined directly without the need to assume a density model, as has been done with single-spacecraft observations. The separation of Helios-A and -B has also provided measurements of burst directivity at low frequencies. For the March 28 burst the intensity observed from near the source longitude (Helios-B) was 3-10dB greater than that from 60 deg west of the source (Helios-A)

  16. Low frequency spectra of type III solar radio bursts

    NASA Technical Reports Server (NTRS)

    Weber, R. R.

    1978-01-01

    Flux density spectra have been determined for 91 simple type III solar bursts observed by the Goddard Space Flight Center radio astronomy experiment on the IMP-6 spacecraft during 1971 and 1972. Spectral peaks were found to occur at frequencies ranging from 44 kHz up to 2500 kHz. Half of the bursts peaked between 250 kHz and 900 kHz, corresponding to emission at solar distances of about 0.3 to 0.1 AU. Maximum burst flux density sometimes exceeds 10 to the -14th W/sq m/Hz. The primary factor controlling the spectral peak frequency of these bursts appears to be a variation in intrinsic power radiated by the source as the exciter moves outward from the sun, rather than radio propagation effects between the source and IMP-6. Thus, a burst spectrum strongly reflects the evolution of the properties of the exciting electron beam, and according to current theory, beam deceleration could help account for the observations.

  17. The Structure and Function of Type III Secretion Systems

    PubMed Central

    Notti, Ryan Q.; Stebbins, C. Erec

    2015-01-01

    ARTICLE SUMMARY Type III secretion systems (T3SS) afford gram-negative bacteria a most intimate means of altering the biology of their eukaryotic hosts — the direct delivery of effector proteins from the bacterial cytoplasm to that of the eukaryote. This incredible biophysical feat is accomplished by nanosyringe “injectisomes,” which form a conduit across the three plasma membranes, peptidoglycan layer and extracellular space that form a barrier to the direct delivery of proteins from bacterium to host. The focus of this chapter is T3SS function at the structural level; we will summarize the core findings that have shaped our understanding of the structure and function of these systems and highlight recent developments in the field. In turn, we describe the T3SS secretory apparatus, consider its engagement with secretion substrates, and discuss the post-translational regulation of secretory function. Lastly, we close with a discussion of the future prospects for the interrogation of structure-function relationships in the T3SS. PMID:26999392

  18. Functional Activation of the Flagellar Type III Secretion Export Apparatus

    PubMed Central

    Phillips, Andrew M.; Calvo, Rebecca A.; Kearns, Daniel B.

    2015-01-01

    Flagella are assembled sequentially from the inside-out with morphogenetic checkpoints that enforce the temporal order of subunit addition. Here we show that flagellar basal bodies fail to proceed to hook assembly at high frequency in the absence of the monotopic protein SwrB of Bacillus subtilis. Genetic suppressor analysis indicates that SwrB activates the flagellar type III secretion export apparatus by the membrane protein FliP. Furthermore, mutants defective in the flagellar C-ring phenocopy the absence of SwrB for reduced hook frequency and C-ring defects may be bypassed either by SwrB overexpression or by a gain-of-function allele in the polymerization domain of FliG. We conclude that SwrB enhances the probability that the flagellar basal body adopts a conformation proficient for secretion to ensure that rod and hook subunits are not secreted in the absence of a suitable platform on which to polymerize. PMID:26244495

  19. Dynamics and efficiency of type III solar radio emission

    NASA Technical Reports Server (NTRS)

    Robinson, P. A.; Cairns, I. H.; Willes, A. J.

    1994-01-01

    Existing calculations of nonlinear coupling coefficients for fundamental and harmonic emission via three-wave interactions are refined and used to calculate the conversion efficiency of Langmuir energy into electromagnetic waves when the Langmuir waves have the observed bursty form. Resulting field strengths for harmonic emission are found to be consistent with typical International Sun Earth Explorer 3 (ISSE 3) observations at 1 AU. Fundamental emission at 1 AU is found to proceed only when stimulated by the presence of a source of ion sound waves. However, it is argued that electrostatic decay of Langmuir waves can supply the necessary waves provided the driving electron beam is sufficiently fast. Under these conditions, the predicted fundamental field strengths can account for both the highest and typical fields observed; they also dominate the predicted harmonic fields, consistent with observations. This mechanism is also consistent with previous observations that fundamental emission generally occurs early in type III events, when the beam is fastest. For typical parameters it is shown that neither fundamental nor harmonic emission saturates its respective source instability, contrary to previous assumptions. However, saturation cannot be ruled out under particularly favorable conditions.

  20. Characterization of resistant starch type III from banana (Musa acuminata).

    PubMed

    Lehmann, Undine; Jacobasch, Gisela; Schmiedl, Detlef

    2002-08-28

    Banana starch (Musa acuminata var. Nandigobe) was evaluated for its use in generating resistant starch (RS) type III. Structural, physicochemical, and biological properties of these products were analyzed. The investigated process includes debranching of the native starch and retrogradation under different storage temperatures and starch concentrations. After enzymatic debranching, a high amount of low-molecular-weight polymers with a degree of polymerization between 10 and 35 glucose units beside a higher molecular weight fraction were found. The resulting products comprised RS contents of about 50%. After heat-moisture treatment, the RS yield increased up to 84%. Peak temperatures of about 145 degrees C found in DSC measurements pointed to a high thermal stability of the RS products. In vitro fermentations of the RS products, carried out with intestinal microflora of healthy humans, resulted in a molar ratio of acetate:propionate:butyrate of about 49:17:34. The established method allowed the production of a high-quality RS with prebiotic properties for health preventing applications.

  1. Atomic model of the type III secretion system needle.

    PubMed

    Loquet, Antoine; Sgourakis, Nikolaos G; Gupta, Rashmi; Giller, Karin; Riedel, Dietmar; Goosmann, Christian; Griesinger, Christian; Kolbe, Michael; Baker, David; Becker, Stefan; Lange, Adam

    2012-05-20

    Pathogenic bacteria using a type III secretion system (T3SS) to manipulate host cells cause many different infections including Shigella dysentery, typhoid fever, enterohaemorrhagic colitis and bubonic plague. An essential part of the T3SS is a hollow needle-like protein filament through which effector proteins are injected into eukaryotic host cells. Currently, the three-dimensional structure of the needle is unknown because it is not amenable to X-ray crystallography and solution NMR, as a result of its inherent non-crystallinity and insolubility. Cryo-electron microscopy combined with crystal or solution NMR subunit structures has recently provided a powerful hybrid approach for studying supramolecular assemblies, resulting in low-resolution and medium-resolution models. However, such approaches cannot deliver atomic details, especially of the crucial subunit-subunit interfaces, because of the limited cryo-electron microscopic resolution obtained in these studies. Here we report an alternative approach combining recombinant wild-type needle production, solid-state NMR, electron microscopy and Rosetta modelling to reveal the supramolecular interfaces and ultimately the complete atomic structure of the Salmonella typhimurium T3SS needle. We show that the 80-residue subunits form a right-handed helical assembly with roughly 11 subunits per two turns, similar to that of the flagellar filament of S. typhimurium. In contrast to established models of the needle in which the amino terminus of the protein subunit was assumed to be α-helical and positioned inside the needle, our model reveals an extended amino-terminal domain that is positioned on the surface of the needle, while the highly conserved carboxy terminus points towards the lumen.

  2. On the correlation between exciter duration and decay constant of solar decameter Type III radio bursts

    NASA Astrophysics Data System (ADS)

    Subramanian, K. R.; Krishan, V.; Sastry, Ch. V.

    1981-04-01

    It is observed that while there exists a strong correlation between the decay constant and the exciter duration for isolated Type III radio bursts, it is absent for those Type III radio bursts which are preceded by Type IIIb radio bursts. A possible theoretical explanation for the presence of correlation in one case and lack of it in the other is proposed.

  3. Exploration of Chlamydial Type III Secretion System Reconstitution in Escherichia coli

    PubMed Central

    Bao, Xiaofeng; Beatty, Wandy L.; Fan, Huizhou

    2012-01-01

    Background Type III secretion system is a virulent factor for many pathogens, and is thought to play multiple roles in the development cycle and pathogenesis of chlamydia, an important human pathogen. However, due to the obligate intracellular parasitical nature of chlamydiae and a lack of convenient genetic methodology for the organisms, very limited approaches are available to study the chlamydial type III secretion system. In this study, we explored the reconstitution of a chlamydial type III secretion in Escherichia coli. Results We successfully cloned all 6 genomic DNA clusters of the chlamydial type III secretion system into three bacterial plasmids. 5 of the 6 clusters were found to direct mRNA synthesis from their own promoters in Escherichia coli transformed with the three plasmids. Cluster 5 failed to express mRNA using its own promoters. However, fusion of cluster 5 to cluster 6 resulted in the expression of cluster 5 mRNA. Although only two of the type III secretion system proteins were detected transformed E. coli due to limited antibody availability, type III secretion system-like structures were detected in ultrathin sections in a small proportion of transformed E. coli. Conclusions We have successfully generated E. coli expressing all genes of the chlamydial type III secretion system. This serves as a foundation for optimal expression and assembly of the recombinant chlamydial type III secretion system, which may be extremely useful for the characterization of the chlamydial type III secretion system and for studying its role in chlamydial pathogenicity. PMID:23239989

  4. Statistical study of solar type III bursts and auroral kilometric radiation onsets

    SciTech Connect

    Farrell, W.M.; Gurnett, D.A.

    1985-10-01

    Simultaneous occurrences of type III solar radio bursts and auroral kilometric radiation were observed by Calvert using ISEE 1 spectrograms. He presented evidence suggesting that the incoming type III burst stimulates the onset of auroral kilometric radiation (AKR). This paper presents a statistical study of the correlation between type III bursts and auroral kilometric radiation. A superposed epoch analysis was performed on as many as 186 type III events. The type III bursts were detected by the ISEE 3 spacecraft on the sunward side of the earth. At the same time the IMP 8 spacecraft was used to detect onsets of kilometric radiation on the nightside of the earth. For each event the intensities measured by ISEE 3(type III intensities) were subtracted from the intensities measured by IMP 8 (type III and possible AKR intensities). The resulting intensities for each event were then added to determine if kilometric radiation was preferentially observed following a type III burst. This analysis was performed at frequencies of 100, 178, and 500 kHz. The results of this study show that a statistically significant correlation exists between incoming type III bursts from the sun and kilometric radiation from the earth.

  5. RIEGER-TYPE PERIODICITY IN THE OCCURRENCE OF SOLAR TYPE III RADIO BURSTS

    SciTech Connect

    Lobzin, V. V.; Cairns, Iver H.; Robinson, P. A.

    2012-08-01

    This Letter presents the first observations of a Rieger-type periodicity with the period of 156{sub -9}{sup +19} days in the occurrence rate of solar coronal type III radio bursts. The periodicity was detected during the time interval from 2000 June 22 to 2003 December 31. This interval partially contains the maximum and the declining phase of solar cycle 23. The radio spectra were provided by the Learmonth Solar Radio Observatory in Western Australia, part of the USAF Radio Solar Telescope Network.

  6. Yersinia type III effectors perturb host innate immune responses

    PubMed Central

    Pha, Khavong; Navarro, Lorena

    2016-01-01

    The innate immune system is the first line of defense against invading pathogens. Innate immune cells recognize molecular patterns from the pathogen and mount a response to resolve the infection. The production of proinflammatory cytokines and reactive oxygen species, phagocytosis, and induced programmed cell death are processes initiated by innate immune cells in order to combat invading pathogens. However, pathogens have evolved various virulence mechanisms to subvert these responses. One strategy utilized by Gram-negative bacterial pathogens is the deployment of a complex machine termed the type III secretion system (T3SS). The T3SS is composed of a syringe-like needle structure and the effector proteins that are injected directly into a target host cell to disrupt a cellular response. The three human pathogenic Yersinia spp. (Y. pestis, Y. enterocolitica, and Y. pseudotuberculosis) are Gram-negative bacteria that share in common a 70 kb virulence plasmid which encodes the T3SS. Translocation of the Yersinia effector proteins (YopE, YopH, YopT, YopM, YpkA/YopO, and YopP/J) into the target host cell results in disruption of the actin cytoskeleton to inhibit phagocytosis, downregulation of proinflammatory cytokine/chemokine production, and induction of cellular apoptosis of the target cell. Over the past 25 years, studies on the Yersinia effector proteins have unveiled tremendous knowledge of how the effectors enhance Yersinia virulence. Recently, the long awaited crystal structure of YpkA has been solved providing further insights into the activation of the YpkA kinase domain. Multisite autophosphorylation by YpkA to activate its kinase domain was also shown and postulated to serve as a mechanism to bypass regulation by host phosphatases. In addition, novel Yersinia effector protein targets, such as caspase-1, and signaling pathways including activation of the inflammasome were identified. In this review, we summarize the recent discoveries made on Yersinia

  7. Yersinia type III effectors perturb host innate immune responses.

    PubMed

    Pha, Khavong; Navarro, Lorena

    2016-02-26

    The innate immune system is the first line of defense against invading pathogens. Innate immune cells recognize molecular patterns from the pathogen and mount a response to resolve the infection. The production of proinflammatory cytokines and reactive oxygen species, phagocytosis, and induced programmed cell death are processes initiated by innate immune cells in order to combat invading pathogens. However, pathogens have evolved various virulence mechanisms to subvert these responses. One strategy utilized by Gram-negative bacterial pathogens is the deployment of a complex machine termed the type III secretion system (T3SS). The T3SS is composed of a syringe-like needle structure and the effector proteins that are injected directly into a target host cell to disrupt a cellular response. The three human pathogenic Yersinia spp. (Y. pestis, Y. enterocolitica, and Y. pseudotuberculosis) are Gram-negative bacteria that share in common a 70 kb virulence plasmid which encodes the T3SS. Translocation of the Yersinia effector proteins (YopE, YopH, YopT, YopM, YpkA/YopO, and YopP/J) into the target host cell results in disruption of the actin cytoskeleton to inhibit phagocytosis, downregulation of proinflammatory cytokine/chemokine production, and induction of cellular apoptosis of the target cell. Over the past 25 years, studies on the Yersinia effector proteins have unveiled tremendous knowledge of how the effectors enhance Yersinia virulence. Recently, the long awaited crystal structure of YpkA has been solved providing further insights into the activation of the YpkA kinase domain. Multisite autophosphorylation by YpkA to activate its kinase domain was also shown and postulated to serve as a mechanism to bypass regulation by host phosphatases. In addition, novel Yersinia effector protein targets, such as caspase-1, and signaling pathways including activation of the inflammasome were identified. In this review, we summarize the recent discoveries made on Yersinia

  8. A note on tilted Bianchi type VIh models: the type III bifurcation

    NASA Astrophysics Data System (ADS)

    Coley, A. A.; Hervik, S.

    2008-10-01

    In this note we complete the analysis of Hervik, van den Hoogen, Lim and Coley (2007 Class. Quantum Grav. 24 3859) of the late-time behaviour of tilted perfect fluid Bianchi type III models. We consider models with dust, and perfect fluids stiffer than dust, and eludicate the late-time behaviour by studying the centre manifold which dominates the behaviour of the model at late times. In the dust case, this centre manifold is three-dimensional and can be considered a double bifurcation as the two parameters (h and γ) of the type VIh model are varied. We therefore complete the analysis of the late-time behaviour of tilted ever-expanding Bianchi models of types I VIII.

  9. Immunomodulation by the Pseudomonas syringae HopZ Type III Effector Family in Aribidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas syringae employs a type III secretion system to inject 20-30 different type III effector (T3SE) proteins into plant host cells. A major role of T3SEs is to suppress plant immune responses and promote bacterial infection. The YopJ/HopZ acetyltransferases are a superfamily of T3SEs found i...

  10. The Effects of Non-Normality on Type III Error for Comparing Independent Means

    ERIC Educational Resources Information Center

    Mendes, Mehmet

    2007-01-01

    The major objective of this study was to investigate the effects of non-normality on Type III error rates for ANOVA F its three commonly recommended parametric counterparts namely Welch, Brown-Forsythe, and Alexander-Govern test. Therefore these tests were compared in terms of Type III error rates across the variety of population distributions,…

  11. Behind the lines–actions of bacterial type III effector proteins in plant cells

    PubMed Central

    Büttner, Daniela

    2016-01-01

    Pathogenicity of most Gram-negative plant-pathogenic bacteria depends on the type III secretion (T3S) system, which translocates bacterial effector proteins into plant cells. Type III effectors modulate plant cellular pathways to the benefit of the pathogen and promote bacterial multiplication. One major virulence function of type III effectors is the suppression of plant innate immunity, which is triggered upon recognition of pathogen-derived molecular patterns by plant receptor proteins. Type III effectors also interfere with additional plant cellular processes including proteasome-dependent protein degradation, phytohormone signaling, the formation of the cytoskeleton, vesicle transport and gene expression. This review summarizes our current knowledge on the molecular functions of type III effector proteins with known plant target molecules. Furthermore, plant defense strategies for the detection of effector protein activities or effector-triggered alterations in plant targets are discussed. PMID:27526699

  12. Type III solar radio bursts and the fundamental-harmonic hypothesis

    NASA Technical Reports Server (NTRS)

    Rosenberg, H.

    1975-01-01

    The observational evidence is reviewed for the occurrence of type III solar radio bursts in pairs with frequency ratio two to one. We show that the observations can be explained under the hypothesis that there is a tendency for a type III burst to be followed by a second burst within approximately one second. This explanation leads to fewer difficulties than the hypothesis that type III bursts occur in pairs, one member being emitted at the fundamental of the local coronal plasma frequency, the other at its second harmonic. We conclude that in general, type III bursts are emitted at the second harmonic of the plasma frequency and that type III theories should account for this and only under very special circumstances (which are rare) for the emission at the fundamental and the second harmonic.

  13. Metric type-III burst asymmetry relative to simple bipolar active regions

    SciTech Connect

    Jackson, B.V.

    1986-01-01

    Metric type-III solar radio burst positions are compared spatially and temporally to underlying active-region geometry. The positions of these radio bursts have an asymmetric location distribution relative to simple bipolar regions. The type-III bursts show a tendency to occur nearer the leading active region - an association shown before from type-III burst and magnetic-field-polarity measurements. The type-III burst also generally occur to the left of the outward- to inward-directed magnetic field. The asymmetry relative to the outward directed magnetic field has a sense that is consistent with a mechanism of type-III burst production that involves a pre-existing coronal current system situated between expanding closed and open magnetic field lines.

  14. The unique regulation and functions of type III interferons in antiviral immunity.

    PubMed

    Odendall, Charlotte; Kagan, Jonathan C

    2015-06-01

    Type I interferons (IFNs) were long considered to be the sole IFN species produced by virus-infected cells until the discovery of type III IFNs (IFNλs), decades later. Like type I IFNs, type III IFNs are induced by and protect against viral infections, leading to the initial conclusion that the two IFN species are identical in regulation and biological functions. However, the two systems differ in the tissue expression of their receptor, resulting in different roles in vivo. The unique nature of IFNλs has been further demonstrated by recent studies revealing differences in the regulation of type I and III IFN expression, and how these proteins elicit specific cellular responses. This review focuses on the distinctive features of type III IFNs in antiviral innate immunity.

  15. Type III Protein Secretion Systems in Bacterial Pathogens of Animals and Plants

    PubMed Central

    Hueck, Christoph J.

    1998-01-01

    Various gram-negative animal and plant pathogens use a novel, sec-independent protein secretion system as a basic virulence mechanism. It is becoming increasingly clear that these so-called type III secretion systems inject (translocate) proteins into the cytosol of eukaryotic cells, where the translocated proteins facilitate bacterial pathogenesis by specifically interfering with host cell signal transduction and other cellular processes. Accordingly, some type III secretion systems are activated by bacterial contact with host cell surfaces. Individual type III secretion systems direct the secretion and translocation of a variety of unrelated proteins, which account for species-specific pathogenesis phenotypes. In contrast to the secreted virulence factors, most of the 15 to 20 membrane-associated proteins which constitute the type III secretion apparatus are conserved among different pathogens. Most of the inner membrane components of the type III secretion apparatus show additional homologies to flagellar biosynthetic proteins, while a conserved outer membrane factor is similar to secretins from type II and other secretion pathways. Structurally conserved chaperones which specifically bind to individual secreted proteins play an important role in type III protein secretion, apparently by preventing premature interactions of the secreted factors with other proteins. The genes encoding type III secretion systems are clustered, and various pieces of evidence suggest that these systems have been acquired by horizontal genetic transfer during evolution. Expression of type III secretion systems is coordinately regulated in response to host environmental stimuli by networks of transcription factors. This review comprises a comparison of the structure, function, regulation, and impact on host cells of the type III secretion systems in the animal pathogens Yersinia spp., Pseudomonas aeruginosa, Shigella flexneri, Salmonella typhimurium, enteropathogenic Escherichia coli

  16. Low-Frequency Type III Bursts and Solar Energetic Particle Events

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Nat; Makela, Pertti

    2010-01-01

    We analyzed the coronal mass ejections (CMEs), flares, and type 11 radio bursts associated with a set of six low frequency (<14 MHz) extended type III bursts from active region 10588. The durations were measured at 1 and 14 MHz using high resolution data from Wind/WAVES and were within the range (>15 min) normally used to define these bursts. All but one of the type III bursts was not associated with a type 11 burst in the metric or longer wavelength domains. The burst without type 11 burst also lacked a solar energetic particle (SEP) event at energies >25 MeV. The 1-MHz duration of the type III burst (28 min) is near the median value of type III durations found for gradual SEP events and ground level enhancement (GLE) events. Yet, there was no sign of SEP events. On the other hand, two other type III bursts from the same active region had similar duration but accompanied by WAVES type 11 bursts; these bursts were also accompanied by SEP events detected by SOHO/ERNE. The CMEs were of similar speeds and the flares are also of similar size and duration. This study suggests that the type III burst duration may not be a good indicator of an SEP event.

  17. Distributions of types I, II and III collagen by region in the human supraspinatus tendon.

    PubMed

    Buckley, Mark R; Evans, Elisabeth B; Matuszewski, Paul E; Chen, Yi-Ling; Satchel, Lauren N; Elliott, Dawn M; Soslowsky, Louis J; Dodge, George R

    2013-01-01

    The mechanical properties of the human supraspinatus tendon (SST) are highly heterogeneous and may reflect an important adaptive response to its complex, multiaxial loading environment. However, these functional properties are associated with a location-dependent structure and composition that have not been fully elucidated. Therefore, the objective of this study was to determine the concentrations of types I, II and III collagen in six distinct regions of the SST and compare changes in collagen concentration across regions with local changes in mechanical properties. We hypothesized that type I collagen content would be high throughout the tendon, type II collagen would be restricted to regions of compressive loading and type III collagen content would be high in regions associated with damage. We further hypothesized that regions of high type III collagen content would correspond to regions with low tensile modulus and a low degree of collagen alignment. Although type III collagen content was not significantly higher in regions that are frequently damaged, all other hypotheses were supported by our results. In particular, type II collagen content was highest near the insertion while type III collagen was inversely correlated with tendon modulus and collagen alignment. The measured increase in type II collagen under the coracoacromial arch provides evidence of adaptation to compressive loading in the SST. Moreover, the structure-function relationship between type III collagen content and tendon mechanics established in this study demonstrates a mechanism for altered mechanical properties in pathological tendons and provides a guideline for identifying therapeutic targets and pathology-specific biomarkers.

  18. Frontal Sinus Patency after Extended Frontal Sinusotomy Type III

    PubMed Central

    Hajbeygi, Mansour; Nadjafi, Ali; Amali, Amin; Saedi, Babak; Sadrehosseini, Seyed Mousa

    2016-01-01

    Introduction: The surgical management of chronic frontal sinus disorders remains a challenge for rhinologists. The aim of this study was to evaluate the result of Draf III in a series of patients who underwent this procedure. Materials and Methods: Twenty patients were included in this study. Demographic data, history of prior surgery, asthma, aspirin sensitivity and Lund–Mackay score were recorded. A visual analog scale was used for frontal-related symptoms. Patients were followed for a mean duration of 17.5 months and the patency of the frontal sinus ostium was closely monitored. Results: Fifteen patients with chronic frontal sinusitis, two patients with mucoceles, two with malignancy, and one with osteoma underwent Draf III. The mean symptoms score significantly decreased from 5.9 to 3. No ostial closure was seen in the follow-up period. Among 15 patients with chronic frontal sinusitis, 12 had patent ostia of whom three had significant stenosis. All patients with mucocele and osteoma had patent ostia in the follow-up period but patients with sinonasal malignancy showed significant stenosis. Conclusion: Draf III frontal sinusotomy is successful in alleviating patient symptoms and the frontal sinus neo-ostium will remain patent in long-term follow-up of most patients. Revision surgery will be required in some cases, which seems to be related to the nature of the underlying chronic sinus diseases. PMID:27738610

  19. "Do Type III-associated escaping electron beams cool the corona?"

    NASA Astrophysics Data System (ADS)

    Saint-Hilaire, P.; Wang, L.; Vilmer, N.; Kerdraon, A.

    2012-12-01

    A recent study of decimetric Type III radio burst emission from data from the Nancay Radio Heliograph will be presented. It examined sizes, locations, and fluxes of close to 10'000 decimetric Type III bursts. The flux study suggests that electron beams related to Type III emission could be responsible for carrying energy away from the corona in a proportion similar to EUV nanoflares. This tentative conclusion was reached from comparing Type III dN/dS distributions to the dN/dS of EUV/SXR nano-/micro-flares. The biggest uncertainty is the radiative efficiency, i.e. the ratio of radiated energy in decimetric Type III bursts and the energy of the electrons in the beams associated with them. We will constrain this value through other, new observations: we have already computed the amount of Type III radiated energy from NRH observations, and we will now compare them with the amount of energy in the corresponding beam electron detected in-situ by the Wind spacecraft. Given our sample of close to 10'000 decimetric Type IIIs, we expect a decent amount of in-situ beam energy estimates from magnetically connected events. Moreover, we will compare with X-ray-derived energies from corresponding RHESSI (micro)flares, when such an association exists.

  20. Do Type III-associated Escaping Electron Beams Cool The Corona?

    NASA Astrophysics Data System (ADS)

    Saint-Hilaire, Pascal; Wang, L.; Christe, S. D.; Vilmer, N.; Kerdraon, A.; Lin, R. P.

    2012-05-01

    A recent study of decimetric Type III radio burst emission from data from the Nancay Radio Heliograph (NRH) will be presented. It examined sizes, locations, and fluxes of close to 10'000 decimetric Type III bursts. The flux study suggests that electron beams related to Type III emission could be responsible for carrying energy away from the corona in a proportion similar to that of EUV nanoflare heating. This tentative conclusion was reached from comparing Type III dN/dS distributions to the dN/dS of EUV/SXR nano-/micro-flares. The biggest uncertainty is the radiative efficiency, i.e. the ratio of radiated energy in decimetric Type III bursts and the energy of the electrons in the beams associated with them. We will constrain this value through other, new observations: we have already computed the amount of Type III radiated energy from NRH observations, and we will now compare them with the amount of energy in the corresponding beam electron detected in-situ by the Wind spacecraft. Given our sample of close to 10'000 decimetric Type IIIs, we expect a decent amount of in-situ beam energy estimates from magnetically connected events. Moreover, we will compare with X-ray-derived energies from corresponding RHESSI (micro)flares, when such an association exists.

  1. A computer simulation study of type III radio burst propagation through the solar corona

    NASA Astrophysics Data System (ADS)

    Itkina, M. A.; Levin, B. N.

    1992-01-01

    Type III solar radio burst propagation through large-scale coronal structure is numerically simulated. It is shown that radio wave refraction in an overdense streamer results in an increase of the apparent radial distance of the type III fundamental source and produces a broadening of the radiation polar diagram in agreement with the observations. It is also verified that the well-known fine frequency structure of type IIIb emission can be due to the fibrous character of the streamer.

  2. [Prophylactic use of icatibant before tracheal intubation of a patient with hereditary angioedema type III. (A literature review of perioperative management of patients with hereditary angioedema type III)].

    PubMed

    Iturri Clavero, F; González Uriarte, A; Tamayo Medel, G; Gamboa Setién, P M

    2014-01-01

    Type III hereditary angioedema is a rare familial disorder that has recently been described as a separate condition. Triggers for episodes of angioedema include surgery, dental procedures, and tracheal intubation maneuvers. Since episodes affecting the upper airway are potentially life-threatening, prophylactic treatment is recommended in these situations. The use of icatibant (Firazyr(®)), for prevention of angioedema prior to tracheal intubation, is reported in a patient with type iii hereditary angioedema. A literature review on the anesthetic management of this condition was conducted.

  3. LONG-DURATION LOW-FREQUENCY TYPE III BURSTS AND SOLAR ENERGETIC PARTICLE EVENTS

    SciTech Connect

    Gopalswamy, Nat; Maekelae, Pertti

    2010-09-20

    We analyzed the coronal mass ejections (CMEs), flares, and type II radio bursts associated with a set of three complex, long-duration, low-frequency (<14 MHz) type III bursts from active region 10588 in 2004 April. The durations were measured at 1 and 14 MHz using data from Wind/WAVES and were well above the threshold value (>15 minutes) normally used to define these bursts. One of the three type III bursts was not associated with a type II burst, which also lacked a solar energetic particle (SEP) event at energies >25 MeV. The 1 MHz duration of the type III burst (28 minutes) for this event was near the median value of type III durations found for gradual SEP events and ground level enhancement events. Yet, there was no sign of an SEP event. On the other hand, the other two type III bursts from the same active region had similar duration but were accompanied by WAVES type II bursts; these bursts were also accompanied by SEP events detected by SOHO/ERNE. The CMEs for the three events had similar speeds, and the flares also had similar size and duration. This study suggests that the occurrence of a complex, long-duration, low-frequency type III burst is not a good indicator of an SEP event.

  4. Bioinformatics, genomics and evolution of non-flagellar type-III secretion systems: a Darwinian perspective.

    PubMed

    Pallen, Mark J; Beatson, Scott A; Bailey, Christopher M

    2005-04-01

    We review the biology of non-flagellar type-III secretion systems from a Darwinian perspective, highlighting the themes of evolution, conservation, variation and decay. The presence of these systems in environmental organisms such as Myxococcus, Desulfovibrio and Verrucomicrobium hints at roles beyond virulence. We review newly discovered sequence homologies (e.g., YopN/TyeA and SepL). We discuss synapomorphies that might be useful in formulating a taxonomy of type-III secretion. The problem of information overload is likely to be ameliorated by launch of a web site devoted to the comparative biology of type-III secretion ().

  5. Second harmonic generation microscopy differentiates collagen type I and type III in COPD

    NASA Astrophysics Data System (ADS)

    Suzuki, Masaru; Kayra, Damian; Elliott, W. Mark; Hogg, James C.; Abraham, Thomas

    2012-03-01

    The structural remodeling of extracellular matrix proteins in peripheral lung region is an important feature in chronic obstructive pulmonary disease (COPD). Multiphoton microscopy is capable of inducing specific second harmonic generation (SHG) signal from non-centrosymmetric structural proteins such as fibrillar collagens. In this study, SHG microscopy was used to examine structural remodeling of the fibrillar collagens in human lungs undergoing emphysematous destruction (n=2). The SHG signals originating from these diseased lung thin sections from base to apex (n=16) were captured simultaneously in both forward and backward directions. We found that the SHG images detected in the forward direction showed well-developed and well-structured thick collagen fibers while the SHG images detected in the backward direction showed striking different morphological features which included the diffused pattern of forward detected structures plus other forms of collagen structures. Comparison of these images with the wellestablished immunohistochemical staining indicated that the structures detected in the forward direction are primarily the thick collagen type I fibers and the structures identified in the backward direction are diffusive structures of forward detected collagen type I plus collagen type III. In conclusion, we here demonstrate the feasibility of SHG microscopy in differentiating fibrillar collagen subtypes and understanding their remodeling in diseased lung tissues.

  6. Spectroscopic identification of type 2 quasars at z < 1 in SDSS-III/BOSS

    NASA Astrophysics Data System (ADS)

    Yuan, Sihan; Strauss, Michael A.; Zakamska, Nadia L.

    2016-10-01

    The physics and demographics of type 2 quasars remain poorly understood, and new samples of such objects selected in a variety of ways can give insight into their physical properties, evolution, and relationship to their host galaxies. We present a sample of 2758 type 2 quasars at z ≲ 1 from the Sloan Digital Sky Survey-III (SDSS-III)/Baryon Oscillation Spectroscopic Survey (BOSS) spectroscopic data base, selected on the basis of their emission-line properties. We probe the luminous end of the population by requiring the rest-frame equivalent width of [O III] to be >100 Å. We distinguish our objects from star-forming galaxies and type 1 quasars using line widths, standard emission line ratio diagnostic diagrams at z < 0.52 and detection of [Ne V]λ3426 Å at z > 0.52. The majority of our objects have [O III] luminosities in the range 1.2 × 1042-3.8 × 1043 erg s-1 and redshifts between 0.4 and 0.65. Our sample includes over 400 type 2 quasars with incorrectly measured redshifts in the BOSS data base; such objects often show kinematic substructure or outflows in the [O III] line. The majority of the sample has counterparts in the Wide-field Infrared Survey Explorer survey, with median infrared luminosity νLν[12 μm] = 4.2 × 1044 erg s- 1. Only 34 per cent of the newly identified type 2 quasars would be selected by infrared colour cuts designed to identify obscured active nuclei, highlighting the difficulty of identifying complete samples of type 2 quasars. We make public the multi-Gaussian decompositions of all [O III] profiles for the new sample and for 568 type 2 quasars from SDSS I/II, together with non-parametric measures of the [O III] line profile shapes. We also identify over 600 candidate double-peaked [O III] profiles.

  7. The stimulation of auroral kilometric radiation by type III solar radio bursts

    NASA Technical Reports Server (NTRS)

    Calvert, W.

    1981-01-01

    It has been found that the onset of auroral kilometric radiation (AKR) frequently coincides with the arrival of type III solar radio bursts. Although the AKR onsets are usually abrupt and appear to be spontaneous, they sometimes develop from a discrete frequency near the leading edge of a type III burst or sometimes occur at progressively lower frequencies following that edge. From this, and the absence of the related solar electrons in specific cases, it was concluded that the incoming type III waves were sometimes responsible for stimulating auroral kilometric radiation. It was estimated that intense, isolated type III bursts were capable of stimulating AKR roughly one third of the time, and that at least ten percent of the observed AKR onsets could be attributed to these and weaker bursts, including some barely detectable by the ISEE plasma wave receivers.

  8. Stimulation of auroral kilometric radiation by type III solar radio bursts

    SciTech Connect

    Calvert, W.

    1981-10-01

    It has been found that the onset of auroral kilometric radiation (AKR) frequently coincides with the arrival of type III solar radio bursts. Although the AKR onsets are usually abrupt and appear to be spontaneous, they sometimes develop from a discrete frequency near the leading edge of a type III burst or sometimes occur at progressively lower frequencies following that edge. From this, and the absence of the related solar electrons in specific cases, it was concluded that the incoming type III waves were sometimes responsible for stimulating auroral kilometric radiation. It was estimated that intense, isolated type III bursts were capable of stimulating AKR roughly one third of the time, and that at least ten percent of the observed AKR onsets could be attributed to these and weaker bursts, including some barely detectable by the ISEE plasma wave receivers.

  9. Mucin model for group B type III streptococcal infection in mice.

    PubMed Central

    Fleming, D O

    1980-01-01

    An experimental murine infection was established by the intraperitoneal injection of a log-phase culture of a laboratory reference strain of Streptococcus agalactiae, Lancefield group B, type III (strain SS620), suspended in sterile hog gastric mucin. The enhancement of streptococcal virulence was measured by a significantly increased mortality in outbred ICR Swiss mice. An inbred C57BL6 strain of mice was resistant to the mucin-bacterial combination. Mucin, treated with Desferal to chelate the iron, did not lose the capacity to enhance the virulence of group B, type III streptococci in ICR Swiss mice. Iron-dextran was not a suitable substitute for mucin and failed to enhance the virulence of group B, type III streptococci. The results of these studies indicate that iron is not the resistance-lowering factor in this group B, type III streptococci-mucin model. PMID:6155334

  10. A New Look at Type-III Bursts and Their Use as Coronal Diagnostics

    NASA Astrophysics Data System (ADS)

    Tun Beltran, Samuel D.; Cutchin, S.; White, S.

    2015-09-01

    We present meter-wave solar radio spectra of the highest spectro-temporal resolution achieved to date. The observations, obtained with the first station of the Long Wavelength Array (LWA1), show unprecedented detail of solar emissions across a wide bandwidth during a Type-III/IIIb storm. Our flux calibration demonstrates that the LWA1 can detect Type-III bursts much weaker than 1 SFU, much lower than previous observations, and that the distribution of fluxes in these bursts varies with frequency. The high sensitivity and low noise in the data provide strong constraints to models of this type of plasma emission, providing evidence against the idea that Type-IIIb striae are generated from electrons trapped in Langmuir-wave sidebands. The continuous generation of electron beams in the corona revealed by the high density Type-III storm is evidence for ubiquitous magnetic reconnection in the lower corona. Such an abundance of reconnection events not only contributes to the total coronal energy budget, but also provides an engine by which to form the populations of seed particles responsible for proton-rich solar energetic-particle events. An active region (AR) with such levels of reconnection and the accompanying Type-III/IIIb storms is proposed here to be associated with an increase of SEP production if a CME erupts. The data's constraints on existing theories of Type-IIIb production are used to make an association of the observed Type-IIIb storm to specific electron-beam paths with increased inhomogeneities in density, temperature, and/or turbulence. This scenario ties in the observed timing of Type-III and -IIIb storms, constrained theories of Type-III and -IIIb emission, and the ability of the emitting AR to produce a strong SEP event. The result requires but a single observable to cement these ideas, the statistical correlation of Type-III/IIIb activity with SEP-productive AR.

  11. Direct evidence of type III electron streams propagating in coronal streamers

    SciTech Connect

    Kundu, M.R.; Gergely, T.E.; Turner, P.J.; Howard, R.A.

    1983-06-15

    Using two-dimensional solar images at 73.8 MHz, obtained with the Clark Lake Multifrequency Radioheliograph, we present direct evidence that type III electron streams propagate in dense coronal streamers. This evidence is substantiated by the excellent coincidence that we find in position angle between the densest parts of streamers observed with the Solwind coronagraph on the P78-1 satellite and the maximum brightness of type III burst sources.

  12. A comparison of Type III metric radio bursts and global solar potential field models

    NASA Technical Reports Server (NTRS)

    Jackson, B. V.; Levine, R. H.

    1981-01-01

    Evidence of coronal magnetic fields from polarized metric type III radio bursts is compared with (1) global potential field models, (2) direct averages of the observed photospheric magnetic field, and (3) H-alpha synoptic charts. The comparison clearly indicates both that the principal aspects of type III burst radiation are understood and that global potential field models are a significantly more accurate representation of coronal magnetic field structure than either the large-scale photospheric field or H-alpha synoptic charts.

  13. Stratification in the electron beams exciting type III solar radio bursts

    SciTech Connect

    Eremin, A.B.; Zaitsev, V.V.

    1982-07-01

    The opportunities for stratifying the fast-electron beams that generate type III solar radio bursts are discussed. Stratification can result from the growth of electromagnetic instability in a direction normal to the beam velocity, and it will cause the plasma-wave energy density to develop an oscillating space distribution. Analysis of the problem furnishes an explanation of the direct measurements of plasma waves in type III burst sources.

  14. Structural Basis for Substrate Binding and the Catalytic Mechanism of Type III Pantothenate Kinase

    SciTech Connect

    Yang, Kun; Strauss, Erick; Huerta, Carlos; Zhang, Hong

    2008-07-15

    Pantothenate kinase (PanK) catalyzes the first step of the universal five-step coenzyme A (CoA) biosynthetic pathway. The recently characterized type III PanK (PanK-III, encoded by the coaX gene) is distinct in sequence, structure and enzymatic properties from both the long-known bacterial type I PanK (PanK-I, exemplified by the Escherichia coli CoaA protein) and the predominantly eukaryotic type II PanK (PanK-II). PanK-III enzymes have an unusually high K{sub m} for ATP, are resistant to feedback inhibition by CoA, and are unable to utilize the N-alkylpantothenamide family of pantothenate analogues as alternative substrates, thus making type III PanK ineffective in generating CoA analogues as antimetabolites in vivo. Previously, we reported the crystal structure of the PanK-III from Thermotoga maritima and identified it as a member of the 'acetate and sugar kinase/heat shock protein 70/actin' (ASKHA) superfamily. Here we report the crystal structures of the same PanK-III in complex with one of its substrates (pantothenate), its product (phosphopantothenate) as well as a ternary complex structure of PanK-III with pantothenate and ADP. These results are combined with isothermal titration calorimetry experiments to present a detailed structural and thermodynamic characterization of the interactions between PanK-III and its substrates ATP and pantothenate. Comparison of substrate binding and catalytic sites of PanK-III with that of eukaryotic PanK-II revealed drastic differences in the binding modes for both ATP and pantothenate substrates, and suggests that these differences may be exploited in the development of new inhibitors specifically targeting PanK-III.

  15. SOLAR MICRO-TYPE III BURST STORMS AND LONG DIPOLAR MAGNETIC FIELD IN THE OUTER CORONA

    SciTech Connect

    Morioka, A.; Misawa, H.; Obara, T.; Miyoshi, Y.; Masuda, S.; Iwai, K.; Kasaba, Y.

    2015-08-01

    Solar micro-type III radio bursts are elements of the so-called type III storms and are characterized by short-lived, continuous, and weak emissions. Their frequency of occurrence with respect to radiation power is quite different from that of ordinary type III bursts, suggesting that the generation process is not flare-related, but due to some recurrent acceleration processes around the active region. We examine the relationship of micro-type III radio bursts with coronal streamers. We also explore the propagation channel of bursts in the outer corona, the acceleration process, and the escape route of electron beams. It is observationally confirmed that micro-type III bursts occur near the edge of coronal streamers. The magnetic field line of the escaping electron beams is tracked on the basis of the frequency drift rate of micro-type III bursts and the electron density distribution model. The results demonstrate that electron beams are trapped along closed dipolar field lines in the outer coronal region, which arise from the interface region between the active region and the coronal hole. A 22 year statistical study reveals that the apex altitude of the magnetic loop ranges from 15 to 50 R{sub S}. The distribution of the apex altitude has a sharp upper limit around 50 R{sub S} suggesting that an unknown but universal condition regulates the upper boundary of the streamer dipolar field.

  16. Solar Micro-Type III Burst Storms and Long Dipolar Magnetic Field in the Outer Corona

    NASA Astrophysics Data System (ADS)

    Morioka, A.; Miyoshi, Y.; Iwai, K.; Kasaba, Y.; Masuda, S.; Misawa, H.; Obara, T.

    2015-08-01

    Solar micro-type III radio bursts are elements of the so-called type III storms and are characterized by short-lived, continuous, and weak emissions. Their frequency of occurrence with respect to radiation power is quite different from that of ordinary type III bursts, suggesting that the generation process is not flare-related, but due to some recurrent acceleration processes around the active region. We examine the relationship of micro-type III radio bursts with coronal streamers. We also explore the propagation channel of bursts in the outer corona, the acceleration process, and the escape route of electron beams. It is observationally confirmed that micro-type III bursts occur near the edge of coronal streamers. The magnetic field line of the escaping electron beams is tracked on the basis of the frequency drift rate of micro-type III bursts and the electron density distribution model. The results demonstrate that electron beams are trapped along closed dipolar field lines in the outer coronal region, which arise from the interface region between the active region and the coronal hole. A 22 year statistical study reveals that the apex altitude of the magnetic loop ranges from 15 to 50 RS. The distribution of the apex altitude has a sharp upper limit around 50 RS suggesting that an unknown but universal condition regulates the upper boundary of the streamer dipolar field.

  17. Energetic electrons, Type III radio bursts, and impulsive solar flare X-rays

    NASA Technical Reports Server (NTRS)

    Kane, S. R.

    1981-01-01

    Observations of impulsive hard X-ray and type III radio bursts made during the maximum of the last solar activity cycle are analyzed. Spectral measurements of 10-68 keV X-rays were made with the University of California (Berkeley) experiment aboard the OGO 5 satellite. About 20% of impulsive hard X-ray bursts are correlated with type III radio bursts, whereas only about 3% of the reported type III radio bursts are correlated with impulsive X-ray bursts. The location of the associated H gamma flare on the solar disk has little effect on the X-ray-type III burst correlation. The magnitude of the X-ray-type III burst correlation increases systematically with an increase in the intensity and starting frequency of the radio burst, the peak energy and hardness of the X-ray burst, and the peak nonthermal emission measure and spectral hardness of the electron spectrum not less than 20 keV inside the X-ray source. Observations are consistent with the electron populations responsible for both the X-ray and type III emissions accelerated in a single acceleration process; they also suggest a flare model where the primary instability causing electron acceleration during the impulsive phase occurs in the corona.

  18. EM algorithm in estimating the 2- and 3-parameter Burr Type III distributions

    NASA Astrophysics Data System (ADS)

    Ismail, Nor Hidayah Binti; Khalid, Zarina Binti Mohd

    2014-07-01

    The Burr Type III distribution has been applied in the study of income, wage and wealth. It is suitable to fit lifetime data since it has flexible shape and controllable scale parameters. The popularity of Burr Type III distribution increases because it has included the characteristics of other distributions such as logistic and exponential. Burr Type III distribution has two categories: First a two-parameter distribution which has two shape parameters and second a three-parameter distribution which has a scale and two shape parameters. Expectation-maximization (EM) algorithm method is selected in this paper to estimate the two- and three-parameter Burr Type III distributions. Complete and censored data are simulated based on the derivation of pdf and cdf in parametric form of Burr Type III distributions. Then, the EM estimates are compared with estimates from maximum likelihood estimation (MLE) approach through mean square error. The best approach results in estimates with a higher approximation to the true parameters are determined. The result shows that the EM algorithm estimates perform better than the MLE estimates for two- and three-parameter Burr Type III distributions in the presence of complete and censored data.

  19. Solar Flares, Type III Radio Bursts, Coronal Mass Ejections, and Energetic Particles

    NASA Technical Reports Server (NTRS)

    Cane, Hilary V.; Erickson, W. C.; Prestage, N. P.; White, Nicholas E. (Technical Monitor)

    2002-01-01

    In this correlative study between greater than 20 MeV solar proton events, coronal mass ejections (CMEs), flares, and radio bursts it is found that essentially all of the proton events are preceded by groups of type III bursts and all are preceded by CMEs. These type III bursts (that are a flare phenomenon) usually are long-lasting, intense bursts seen in the low-frequency observations made from space. They are caused by streams of electrons traveling from close to the solar surface out to 1 AU. In most events the type III emissions extend into, or originate at, the time when type II and type IV bursts are reported (some 5 to 10 minutes after the start of the associated soft X-ray flare) and have starting frequencies in the 500 to approximately 100 MHz range that often get lower as a function of time. These later type III emissions are often not reported by ground-based observers, probably because of undue attention to type II bursts. It is suggested to call them type III-1. Type III-1 bursts have previously been called shock accelerated (SA) events, but an examination of radio dynamic spectra over an extended frequency range shows that the type III-1 bursts usually start at frequencies above any type II burst that may be present. The bursts sometimes continue beyond the time when type II emission is seen and, furthermore, sometimes occur in the absence of any type II emission. Thus the causative electrons are unlikely to be shock accelerated and probably originate in the reconnection regions below fast CMEs. A search did not find any type III-1 bursts that were not associated with CMEs. The existence of low-frequency type III bursts proves that open field lines extend from within 0.5 radius of the Sun into the interplanetary medium (the bursts start above 100 MHz, and such emission originates within 0.5 solar radius of the solar surface). Thus it is not valid to assume that only closed field lines exist in the flaring regions associated with CMEs and some

  20. 46 CFR 170.135 - Operating information for a vessel with Type III subdivision.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Operating Personnel § 170.135 Operating information for a vessel with Type III subdivision. (a) In addition to the information required in 46 CFR 170.110, the stability booklet of a passenger vessel with Type... 46 Shipping 7 2010-10-01 2010-10-01 false Operating information for a vessel with Type...

  1. [Action of type III IFNs and their roles in immune responses].

    PubMed

    Domagalski, Krzysztof; Tretyn, Andrzej; Pawłowska, Małgorzata; Szczepanek, Joanna; Halota, Waldemar

    2010-10-25

    Type III interferons, also known as IFN-lambda or IL-28/29, are a recently discovered family of IFNs related to both the type I IFNs and interleukin-10 family members. Interferon-lambda is functionally an interferon but structurally it is related to the interleukin-10 family. These novel cytokines are directly induced during viral infection like type-I interferons and signal through a similar JAK-STAT signaling pathway as type I IFN to activate the transcription of a similar set of IFN-stimulated genes (ISG) but use a separate receptor complex. ISG product induced by the type III family of IFNs are associated with immunomodulatory ability, antiviral activity and other effects. The antiviral and immunomodulatory effects of type III interferons make them interesting therapeutics for clinical use. In this review, we summarize the current state of knowledge about the biology of IFN-lambdas and their roles in immune responses via immunomodulatory and antiviral activity.

  2. Avoiding type III, IV, and V errors through collaborative research.

    PubMed

    Yamatani, Hide; Mann, Aaron; Feit, Marvin

    2013-01-01

    Major types of empirical errors reviewed by a number of leading research textbooks include discussions of Type I and Type II errors. However, applied human service researchers can commit other types of errors that should be avoided. The potential benefits of the applied, collaborative research (in contrast to traditional participatory research) include an assurance that the study begins with the "right" questions that are important for community residents. Such research practice also helps generate useful research findings for decisions regarding redistribution of resources and resolving community issues. The aim of collaborative research is not merely to advance scientific understanding, but also to produce empirical findings that are usable for addressing priority needs and problems of distressed communities. A review of a case example (Garfield Community Assessment Study) illustrates the principles and practices of collaborative research.

  3. Avoiding type III, IV, and V errors through collaborative research.

    PubMed

    Yamatani, Hide; Mann, Aaron; Feit, Marvin

    2013-01-01

    Major types of empirical errors reviewed by a number of leading research textbooks include discussions of Type I and Type II errors. However, applied human service researchers can commit other types of errors that should be avoided. The potential benefits of the applied, collaborative research (in contrast to traditional participatory research) include an assurance that the study begins with the "right" questions that are important for community residents. Such research practice also helps generate useful research findings for decisions regarding redistribution of resources and resolving community issues. The aim of collaborative research is not merely to advance scientific understanding, but also to produce empirical findings that are usable for addressing priority needs and problems of distressed communities. A review of a case example (Garfield Community Assessment Study) illustrates the principles and practices of collaborative research. PMID:23879359

  4. Distinct Roles of Type I and Type III Interferons in Intestinal Immunity to Homologous and Heterologous Rotavirus Infections

    PubMed Central

    Balan, Murugabaskar; Tseng, Hsiang-Chi; McElrath, Constance; Smirnov, Sergey V.; Peng, Jianya; Yasukawa, Linda L.; Durbin, Russell K.; Durbin, Joan E.; Greenberg, Harry B.; Kotenko, Sergei V.

    2016-01-01

    Type I (IFN-α/β) and type III (IFN-λ) interferons (IFNs) exert shared antiviral activities through distinct receptors. However, their relative importance for antiviral protection of different organ systems against specific viruses remains to be fully explored. We used mouse strains deficient in type-specific IFN signaling, STAT1 and Rag2 to dissect distinct and overlapping contributions of type I and type III IFNs to protection against homologous murine (EW-RV strain) and heterologous (non-murine) simian (RRV strain) rotavirus infections in suckling mice. Experiments demonstrated that murine EW-RV is insensitive to the action of both types of IFNs, and that timely viral clearance depends upon adaptive immune responses. In contrast, both type I and type III IFNs can control replication of the heterologous simian RRV in the gastrointestinal (GI) tract, and they cooperate to limit extra-intestinal simian RRV replication. Surprisingly, intestinal epithelial cells were sensitive to both IFN types in neonatal mice, although their responsiveness to type I, but not type III IFNs, diminished in adult mice, revealing an unexpected age-dependent change in specific contribution of type I versus type III IFNs to antiviral defenses in the GI tract. Transcriptional analysis revealed that intestinal antiviral responses to RV are triggered through either type of IFN receptor, and are greatly diminished when receptors for both IFN types are lacking. These results also demonstrate a murine host-specific resistance to IFN-mediated antiviral effects by murine EW-RV, but the retention of host efficacy through the cooperative action by type I and type III IFNs in restricting heterologous simian RRV growth and systemic replication in suckling mice. Collectively, our findings revealed a well-orchestrated spatial and temporal tuning of innate antiviral responses in the intestinal tract where two types of IFNs through distinct patterns of their expression and distinct but overlapping sets

  5. Distinct Roles of Type I and Type III Interferons in Intestinal Immunity to Homologous and Heterologous Rotavirus Infections.

    PubMed

    Lin, Jian-Da; Feng, Ningguo; Sen, Adrish; Balan, Murugabaskar; Tseng, Hsiang-Chi; McElrath, Constance; Smirnov, Sergey V; Peng, Jianya; Yasukawa, Linda L; Durbin, Russell K; Durbin, Joan E; Greenberg, Harry B; Kotenko, Sergei V

    2016-04-01

    Type I (IFN-α/β) and type III (IFN-λ) interferons (IFNs) exert shared antiviral activities through distinct receptors. However, their relative importance for antiviral protection of different organ systems against specific viruses remains to be fully explored. We used mouse strains deficient in type-specific IFN signaling, STAT1 and Rag2 to dissect distinct and overlapping contributions of type I and type III IFNs to protection against homologous murine (EW-RV strain) and heterologous (non-murine) simian (RRV strain) rotavirus infections in suckling mice. Experiments demonstrated that murine EW-RV is insensitive to the action of both types of IFNs, and that timely viral clearance depends upon adaptive immune responses. In contrast, both type I and type III IFNs can control replication of the heterologous simian RRV in the gastrointestinal (GI) tract, and they cooperate to limit extra-intestinal simian RRV replication. Surprisingly, intestinal epithelial cells were sensitive to both IFN types in neonatal mice, although their responsiveness to type I, but not type III IFNs, diminished in adult mice, revealing an unexpected age-dependent change in specific contribution of type I versus type III IFNs to antiviral defenses in the GI tract. Transcriptional analysis revealed that intestinal antiviral responses to RV are triggered through either type of IFN receptor, and are greatly diminished when receptors for both IFN types are lacking. These results also demonstrate a murine host-specific resistance to IFN-mediated antiviral effects by murine EW-RV, but the retention of host efficacy through the cooperative action by type I and type III IFNs in restricting heterologous simian RRV growth and systemic replication in suckling mice. Collectively, our findings revealed a well-orchestrated spatial and temporal tuning of innate antiviral responses in the intestinal tract where two types of IFNs through distinct patterns of their expression and distinct but overlapping sets

  6. TYPE III RADIO BURSTS IN CORONAL PLASMAS WITH KAPPA PARTICLE DISTRIBUTIONS

    SciTech Connect

    Li, B.; Cairns, Iver H.

    2013-02-01

    We present the first simulations of type III bursts produced in the corona with suprathermal non-Maxwellian background particles, as inferred from solar wind data and proposed by theories for the corona and solar wind. The coronal background particles are assumed to follow kappa ({kappa}) distributions. The predicted f{sub p} emission of type III bursts is sensitive via the {kappa} index to the presence of suprathermal background particles, where f{sub p} is the local plasma frequency. The simulations show that (1) the speeds v{sub b} of type III beams are much larger (e.g., v{sub b} Almost-Equal-To 0.58c for {kappa} = 5) and so type III bursts drift much faster for low {kappa} ({<=}5) background plasmas than for Maxwellian backgrounds (producing v{sub b} < 0.3c), and (2) f{sub p} emission generated in a {kappa}-distributed background corona has a larger total bandwidth than in a Maxwellian background, for similar onset frequencies. Type III beams are thus more persistent, i.e., extending over larger distances, in {kappa}-distributed corona. Consequently, observations of fast-drifting coronal type III bursts and associated fast electron beams suggest that the ambient electrons in the corona are {kappa}-distributed, at least when such bursts are observed. These results support, from the new viewpoint of nonthermal radio emission, the occasional presence of suprathermal background electrons in the corona and the associated mechanisms (e.g., 'velocity filtration') for coronal heating and solar wind acceleration. The new results also help resolve longstanding issues regarding the speeds and persistence of type III beams, and the production of remotely observable levels of f{sub p} emission despite severe losses during propagation.

  7. Frequency Fine Structures of Type III Bursts Due to Localized Medium-Scale Density Structures Along Paths of Type III Beams

    NASA Astrophysics Data System (ADS)

    Li, B.; Cairns, Iver H.; Robinson, P. A.

    2012-07-01

    Predictions from large-scale kinetic simulations are presented for the effects on coronal type III bursts of localized, medium-scale, enhanced density structures superposed on the coronal background along the paths of type III beams. The simulations show that these density structures can produce pronounced frequency fine structures in type III spectra. Flux intensifications and reductions of f p and 2 f p emission relative to those for the unperturbed background corona occur at frequencies corresponding to the density structures, where f p is the local electron plasma frequency. Frequency fine structures that are intense, slowly drifting, and narrowband, and thus resemble the characteristics of stria bursts, are predicted for the 2 f p emission. The 2 f p results are consistent with the qualitative proposal of Takakura and Yousef ( Solar Phys. 40, 421, 1975) for the interpretation of stria/type IIIb bursts. However, the predicted f p emission is much weaker than the 2 f p emission and generally below observable levels, and the predicted frequency fine structures do not always show stria characteristics. The predictions are thus inconsistent with the qualitative suggestion of Takakura and Yousef and the interpretations of many observers that stria bursts occur more often in f p than in 2 f p emission. The significant discrepancies for f p emission between our numerical calculations and the qualitative proposition of Takakura and Yousef (1975) are mainly caused by: i) differences in the detailed emission processes, ii) neglect of scattering of f p emission off small-scale density fluctuations by Takakura and Yousef (1975), and iii) other simplifications made in both works. Possible improvements to the simulations are discussed, including improvements to the emission processes and the coronal and beam conditions ( e.g., beam speed), in order to produce realistic stria/type IIIb bursts in f p emission.

  8. Identification and characterization of a type III Trichomonas vaginalis virus in the protozoan pathogen Trichomonas vaginalis.

    PubMed

    Bessarab, Irina N; Nakajima, Rui; Liu, Hsing-Wei; Tai, Jung-Hsiang

    2011-02-01

    A type III Trichomonas vaginalis virus, which may be involved in transcriptional regulation of the major surface protein gene P270 of the protozoan pathogen Trichomonas vaginalis, was purified and characterized in the present study. The complete 4844-base-pair complementary DNA sequence of the viral genome reveals overlapping cap and pol genes with a putative ribosomal frame-shifting signal within the overlap region. The type III virus is related more closely to the type II virus than to the type I virus in the sequence of its ribosomal frameshift signal and in its capsid protein. Phylogenetic analysis revealed that these viruses could be grouped in the same clade as a genus distantly related to other genera in the family Totiviridae. Virus-induced P270 gene expression was only evident in Trichomonas vaginalis cells infected with either a type II or type III virus, but not with a type I virus. These findings suggest that transcription of the P270 gene is likely regulated by viral factors common to type II and type III viruses and thus provides important information for future investigation of virus-host interactions.

  9. Identification and characterization of a type III Trichomonas vaginalis virus in the protozoan pathogen Trichomonas vaginalis.

    PubMed

    Bessarab, Irina N; Nakajima, Rui; Liu, Hsing-Wei; Tai, Jung-Hsiang

    2011-02-01

    A type III Trichomonas vaginalis virus, which may be involved in transcriptional regulation of the major surface protein gene P270 of the protozoan pathogen Trichomonas vaginalis, was purified and characterized in the present study. The complete 4844-base-pair complementary DNA sequence of the viral genome reveals overlapping cap and pol genes with a putative ribosomal frame-shifting signal within the overlap region. The type III virus is related more closely to the type II virus than to the type I virus in the sequence of its ribosomal frameshift signal and in its capsid protein. Phylogenetic analysis revealed that these viruses could be grouped in the same clade as a genus distantly related to other genera in the family Totiviridae. Virus-induced P270 gene expression was only evident in Trichomonas vaginalis cells infected with either a type II or type III virus, but not with a type I virus. These findings suggest that transcription of the P270 gene is likely regulated by viral factors common to type II and type III viruses and thus provides important information for future investigation of virus-host interactions. PMID:21110050

  10. The types II and III transforming growth factor-beta receptors form homo-oligomers

    PubMed Central

    1994-01-01

    Affinity-labeling experiments have detected hetero-oligomers of the types I, II, and III transforming growth factor beta (TGF-beta) receptors which mediate intracellular signaling by TGF-beta, but the oligomeric state of the individual receptor types remains unknown. Here we use two types of experiments to show that a major portion of the receptor types II and III forms homo-oligomers both in the absence and presence of TGF-beta. Both experiments used COS-7 cells co-transfected with combinations of these receptors carrying different epitope tags at their extracellular termini. In immunoprecipitation experiments, radiolabeled TGF-beta was bound and cross-linked to cells co-expressing two differently tagged type II receptors. Sequential immunoprecipitations using anti-epitope monoclonal antibodies showed that type II TGF-beta receptors form homo-oligomers. In cells co- expressing epitope-tagged types II and III receptors, a low level of co- precipitation of the ligand-labeled receptors was observed, indicating that some hetero-oligomers of the types II and III receptors exist in the presence of ligand. Antibody-mediated cross-linking studies based on double-labeling immunofluorescence explored co-patching of the receptors at the cell surface on live cells. In cells co-expressing two differently tagged type II receptors or two differently tagged type III receptors, forcing one receptor into micropatches by IgG induced co- patching of the receptor carrying the other tag, labeled by noncross- linking monovalent Fab'. These studies showed that homo-oligomers of the types II and III receptors exist on the cell surface in the absence or presence of TGF-beta 1 or -beta 2. In cells co-expressing types II and III receptors, the amount of heterocomplexes at the cell surface was too low to be detected in the immunofluorescence co-patching experiments, confirming that hetero-oligomers of the types II and III receptors are minor and probably transient species. PMID:8027173

  11. In vitro growth characteristics of simian T-lymphotropic virus type III.

    PubMed Central

    Kannagi, M; Yetz, J M; Letvin, N L

    1985-01-01

    The type C retrovirus simian T-lymphotropic virus type III (STLV-III) has been isolated recently from immunodeficient macaque monkeys at the New England Regional Primate Research Center. The present studies were done to define the in vitro growth characteristics of this agent. STLV-III replicates efficiently in interleukin 2-dependent T-cell cultures of macaque peripheral blood lymphocytes (PBL), less efficiently in such cultures of human and gibbon PBL, and inefficiently in baboon PBL. No replication, as assessed by measuring reverse transcriptase activity in these culture supernatants, could be detected in similarly maintained cultures of chimpanzee, squirrel monkey, and cotton-top tamarin PBL. Like the human acquired immunodeficiency syndrome (AIDS) virus, human T-cell lymphotropic virus III/lymphadenopathy-associated virus (HTLV-III/LAV), STLV-III replicates in T4+ but not T8+ lymphocytes and its infection of macaque and human lymphocytes can be blocked with monoclonal anti-T4 antibodies. STLV-III differs from the human AIDS virus, however, in its apparent inability to grow in the Epstein-Barr virus-transformed B lymphocytes tested, the differing range of nonhuman primate T-cell populations that support its growth, and its less striking toxicity for T lymphocytes. These studies provide further characterization of an agent that will be extremely important in facilitating the development of vaccines and antiviral therapy for AIDS. PMID:2996002

  12. Solar type III radio bursts modulated by homochromous Alfvén waves

    SciTech Connect

    Zhao, G. Q.; Chen, L.; Wu, D. J.

    2013-12-10

    Solar type III radio bursts and their production mechanisms have been intensively studied in both theory and observation and are believed to be the most important signatures of electron acceleration in active regions. Recently, Wu et al. proposed that the electron-cyclotron maser emission (ECME) driven by an energetic electron beam could be responsible for producing type III bursts and pointed out that turbulent Alfvén waves can greatly influence the basic process of ECME via the oscillation of these electrons in the wave fields. This paper investigates effects of homochromous Alfvén waves (HAWs) on ECME driven by electron beams. Our results show that the growth rate of the O-mode wave will be significantly modulated by HAWs. We also discuss possible application to the formation of fine structures in type III bursts, such as so-called solar type IIIb radio bursts.

  13. Measurement of the 3-dimensional positions of type III bursts in the solar corona

    NASA Astrophysics Data System (ADS)

    Poquerusse, M.; Steinberg, J. L.; Caroubalos, C.; Dulk, G. A.; MacQueen, R. M.

    1988-03-01

    The Stereo 5 experiment observed the Sun at 60 and 30 MHz simultaneously on the Earth (Nançay), and on the Soviet spacecraft Mars 7. It recorded many normal type III's and type IIIb's during the period 1974 Jan 10 to 19 at a time when the "stereo" angle Earth-Sun-spacecraft was large enough (≈35°) to allow an accurate triangulation. The time delay Δt of type III bursts between the two observing stations was measured with an uncertainty of ≈0.1 s. A ground interferometer furnished a 2-dimensional position at 75 MHz with an uncertainty of ≈0.1 R_sun;. Combining the two, the authors calculate for the first time the three dimensional positions of type III sources in the corona. Simultaneous observations of the corona in visible light from Skylab allow the apparent radio source positions to be related to slowly evolving coronal structures.

  14. Solar Type III Radio Bursts Modulated by Homochromous Alfvén Waves

    NASA Astrophysics Data System (ADS)

    Zhao, G. Q.; Chen, L.; Wu, D. J.

    2013-12-01

    Solar type III radio bursts and their production mechanisms have been intensively studied in both theory and observation and are believed to be the most important signatures of electron acceleration in active regions. Recently, Wu et al. proposed that the electron-cyclotron maser emission (ECME) driven by an energetic electron beam could be responsible for producing type III bursts and pointed out that turbulent Alfvén waves can greatly influence the basic process of ECME via the oscillation of these electrons in the wave fields. This paper investigates effects of homochromous Alfvén waves (HAWs) on ECME driven by electron beams. Our results show that the growth rate of the O-mode wave will be significantly modulated by HAWs. We also discuss possible application to the formation of fine structures in type III bursts, such as so-called solar type IIIb radio bursts.

  15. On the three harmonics of solar type III bursts at the decameter wavelengths

    NASA Astrophysics Data System (ADS)

    Brazhenko, Anatolii; Pylaev, Oleg; Melnik, Valentin; Konovalenko, Alexandr; Zaqarashvili, Teimuraz; Rucker, Helmut; Frantsuzenko, Anatolii; Dorovskyy, Vladimir

    2014-05-01

    Harmonic structure of type III bursts are explained in terms of plasma emission mechanism. The second harmonic emission is well known. But there are theoretical papers about the third harmonic of type III bursts. And there were observations of the third harmonic of such types of bursts as U, J, V, II. We observed triple type III bursts where frequency ratio is close to 1:2:3. They are structures where type III emission is repeated at the double and triple frequencies. Incidentally, components of triple type III bursts are not only standard type III but also type IIIb bursts. We registered 30 triple bursts during 2011 and 2012 years. Observations were made by radio telescope URAN-2, Poltava, Ukraine. It enables polarization measurements at the frequencies 8 - 32 MHz. URAN-2 allows registration of radio emission with time and frequency resolution 10 ms and 4 kHz correspondingly. We analyze properties of the components of triple bursts and their dependencies on frequency, type of burst and on the position of the component within the triplet. The main properties of the components of triple bursts such as duration and drift rate are similar to those of standard type III and IIIb bursts. We find usual for type III bursts dependencies such as follow: duration decreases with frequency, the type IIIb bursts have always smaller duration at the same frequencies, all bursts drift from high to low frequencies. But we also find the linear dependence of drift rate on frequency. All components of a trio have the same sign of polarization. Polarization of the first component is always the highest in triple bursts. It corresponds to the generally accepted viewpoint about the first harmonic emission. The second and the third components of trio have low polarization. It is typical for the second and the third harmonics according to the plasma radiation mechanism. We discuss possible emission mechanisms and theoretical aspects of observed dependencies. The most of detected regularities

  16. Type III-L Solar Radio Bursts and Solar Energetic Particle Events

    NASA Astrophysics Data System (ADS)

    Duffin, R. T.; White, S. M.; Ray, P. S.; Kaiser, M. L.

    2015-09-01

    A radio-selected sample of fast drift radio bursts with complex structure occurring after the impulsive phase of the associated flare (“Type III-L bursts”) is identified by inspection of radio dynamic spectra from 1 to 180 MHz for over 300 large flares in 2001. An operational definition that takes into account previous work on these radio bursts starting from samples of solar energetic particle (SEP) events is applied to the data, and 66 Type III-L bursts are found in the sample. In order to determine whether the presence of these radio bursts can be used to predict the occurrence of SEP events, we also develop a catalog of all SEP proton events in 2001 using data from the ERNE detector on the SOHO satellite. 68 SEP events are found, for 48 of which we can identify a solar source and hence look for associated Type III-L emission. We confirm previous work that found that most (76% in our sample) of the solar sources of SEP events exhibit radio emission of this type. However, the correlation in the opposite direction is not as strong: starting from a radio-selected sample of Type III-L events, around 64% of the bursts that occur at longitudes magnetically well-connected to the Earth, and hence favorable for detection of SEPs, are associated with SEP events. The degree of association increases when the events have durations over 10 minutes at 1 MHz, but in general Type III-L bursts do not perform any better than Type II bursts in our sample as predictors of SEP events. A comparison of Type III-L timing with the arrival of near-relativistic electrons at the ACE spacecraft is not inconsistent with a common source for the accelerated electrons in both phenomena.

  17. Production of fine structures in type III solar radio bursts due to turbulent density profiles

    SciTech Connect

    Loi, Shyeh Tjing; Cairns, Iver H.; Li, Bo

    2014-07-20

    Magnetic reconnection events in the corona release energetic electron beams along open field lines, and the beams generate radio emission at multiples of the electron plasma frequency f{sub p} to produce type III solar radio bursts. Type III bursts often exhibit irregularities in the form of flux modulations with frequency and/or local temporal advances and delays, and a type IIIb burst represents the extreme case where a type III burst is fragmented into a chain of narrowband features called striae. Remote and in situ spacecraft measurements have shown that density turbulence is ubiquitous in the corona and solar wind, and often exhibits a Kolmogorov power spectrum. In this work, we numerically investigate the effects of one-dimensional macroscopic density turbulence (along the beam direction) on the behavior of type III bursts, and find that this turbulence produces stria-like fine structures in the dynamic spectra of both f{sub p} and 2 f{sub p} radiation. Spectral and temporal fine structures in the predicted type III emission are produced by variations in the scattering path lengths and group speeds of radio emission, and in the locations and sizes of emitting volumes. Moderate turbulence levels yield flux enhancements with much broader half-power bandwidths in f{sub p} than 2 f{sub p} emission, possibly explaining the often observed type IIIb-III harmonic pairs as being where intensifications in 2 f{sub p} radiation are not resolved observationally. Larger turbulence levels producing trough-peak regions in the plasma density profile may lead to broader, resolvable intensifications in 2 f{sub p} radiation, which may account for the type IIIb-IIIb pairs that are sometimes observed.

  18. Production of Fine Structures in Type III Solar Radio Bursts Due to Turbulent Density Profiles

    NASA Astrophysics Data System (ADS)

    Loi, Shyeh Tjing; Cairns, Iver H.; Li, Bo

    2014-07-01

    Magnetic reconnection events in the corona release energetic electron beams along open field lines, and the beams generate radio emission at multiples of the electron plasma frequency fp to produce type III solar radio bursts. Type III bursts often exhibit irregularities in the form of flux modulations with frequency and/or local temporal advances and delays, and a type IIIb burst represents the extreme case where a type III burst is fragmented into a chain of narrowband features called striae. Remote and in situ spacecraft measurements have shown that density turbulence is ubiquitous in the corona and solar wind, and often exhibits a Kolmogorov power spectrum. In this work, we numerically investigate the effects of one-dimensional macroscopic density turbulence (along the beam direction) on the behavior of type III bursts, and find that this turbulence produces stria-like fine structures in the dynamic spectra of both fp and 2 fp radiation. Spectral and temporal fine structures in the predicted type III emission are produced by variations in the scattering path lengths and group speeds of radio emission, and in the locations and sizes of emitting volumes. Moderate turbulence levels yield flux enhancements with much broader half-power bandwidths in fp than 2 fp emission, possibly explaining the often observed type IIIb-III harmonic pairs as being where intensifications in 2 fp radiation are not resolved observationally. Larger turbulence levels producing trough-peak regions in the plasma density profile may lead to broader, resolvable intensifications in 2 fp radiation, which may account for the type IIIb-IIIb pairs that are sometimes observed.

  19. Are type III radio aurorae directly excited by electrostatic ion cyclotron waves

    SciTech Connect

    McDiarmid, D.R.; Watermann, J.; McNamara, A.G. ); Koehler, J.A.; Sofko, G.J. )

    1989-10-01

    In 1981, a network of three 50-MHz radar transmitters and two receivers were operated in the CW mode on the Canadian prairies. The echoes obtained from coherent ionospheric backscatter were divided into segments of 205 ms such that their FFT spectra yielded frequency resolution of 4.9 Hz. The spectra were subsequently averaged over 10 s. Type III spectra (narrow spectra with sub ion-acoustic Doppler shifts) were observed (often simultaneously) on radar links whose wave vector components perpendicular to the geomagnetic field were almost identical while their components parallel to the field were significantly different. From a statistical analysis of more than 300 type III spectra it is inferred that these are in general unlikely to arise from electrostatic ion cyclotron waves directly excited by an essentially linear process. Doppler shifts around 55 Hz were much more frequently observed than around 30 Hz, the occurrence of type III spectra increased with increasing magnetic aspect angle (deviation of the scatter wave vector from perpendicular to the geomagnetic field), and the mean Doppler shifts of type III spectra simultaneously on different radar links went through a minimum for aspect angles between 4{degree} and 7{degree} (depending on the assumed backscatter height). These three results disagree with theoretical expectations. The spectral width the type III echoes decreased linearly with magnetic aspect by about 2 Hz/deg.

  20. Type III polyketide synthase repertoire in Zingiberaceae: computational insights into the sequence, structure and evolution.

    PubMed

    Mallika, Vijayanathan; Aiswarya, Girija; Gincy, Paily Thottathil; Remakanthan, Appukuttan; Soniya, Eppurathu Vasudevan

    2016-07-01

    Zingiberaceae or 'ginger family' is the largest family in the order 'Zingiberales' with more than 1300 species in 52 genera, which are mostly distributed throughout Asia, tropical Africa and the native regions of America with their maximum diversity in Southeast Asia. Many of the members are important spice, medicinal or ornamental plants including ginger, turmeric, cardamom and kaempferia. These plants are distinguished for the highly valuable metabolic products, which are synthesised through phenylpropanoid pathway, where type III polyketide synthase is the key enzyme. In our present study, we used sequence, structural and evolutionary approaches to scrutinise the type III polyketide synthase (PKS) repertoire encoded in the Zingiberaceae family. Highly conserved amino acid residues in the sequence alignment and phylogram suggested strong relationships between the type III PKS members of Zingiberaceae. Sequence and structural level investigation of type III PKSs showed a small number of variations in the substrate binding pocket, leading to functional divergence among these PKS members. Molecular evolutionary studies indicate that type III PKSs within Zingiberaceae evolved under strong purifying selection pressure, and positive selections were rarely detected in the family. Structural modelling and protein-small molecule interaction studies on Zingiber officinale PKS 'a representative from Zingiberaceae' suggested that the protein is comparatively stable without much disorder and exhibited wide substrate acceptance.

  1. Type III polyketide synthase repertoire in Zingiberaceae: computational insights into the sequence, structure and evolution.

    PubMed

    Mallika, Vijayanathan; Aiswarya, Girija; Gincy, Paily Thottathil; Remakanthan, Appukuttan; Soniya, Eppurathu Vasudevan

    2016-07-01

    Zingiberaceae or 'ginger family' is the largest family in the order 'Zingiberales' with more than 1300 species in 52 genera, which are mostly distributed throughout Asia, tropical Africa and the native regions of America with their maximum diversity in Southeast Asia. Many of the members are important spice, medicinal or ornamental plants including ginger, turmeric, cardamom and kaempferia. These plants are distinguished for the highly valuable metabolic products, which are synthesised through phenylpropanoid pathway, where type III polyketide synthase is the key enzyme. In our present study, we used sequence, structural and evolutionary approaches to scrutinise the type III polyketide synthase (PKS) repertoire encoded in the Zingiberaceae family. Highly conserved amino acid residues in the sequence alignment and phylogram suggested strong relationships between the type III PKS members of Zingiberaceae. Sequence and structural level investigation of type III PKSs showed a small number of variations in the substrate binding pocket, leading to functional divergence among these PKS members. Molecular evolutionary studies indicate that type III PKSs within Zingiberaceae evolved under strong purifying selection pressure, and positive selections were rarely detected in the family. Structural modelling and protein-small molecule interaction studies on Zingiber officinale PKS 'a representative from Zingiberaceae' suggested that the protein is comparatively stable without much disorder and exhibited wide substrate acceptance. PMID:27138283

  2. Increased procollagen type III peptide in serum of rabbits exposed to diesel engine exhaust

    SciTech Connect

    Suzuki, Takahito; Kanoh, Takako )

    1990-05-01

    Lung connective tissue is composed of collagen, elastin and proteoglycans. Collagen is the most abundant protein, comprising approximately 11% of normal adult lung and it has been provided at least five polymorphic types in lung. Collagen-producing cells such as fibroblasts and endothelial cells can synthesize procollagen within the cells. Once procollagen is secreted extracellularly, both amino- and carboxy-terminal peptides of procollagen are cleaved by endopeptidases. These peptides can move from the tissue into the blood stream. Therefore, the released peptides of type III procollagen may reflect the degree of biosynthesis of type III collagen, and increased peptide level in type III collagen, and increased peptide level in serum may suggest inflammation or the beginning of fibrosis. In this work, the authors have studied the changes of procollagen type III peptide (P-III-P) levels in sera and bronchoalveolar lavage fluid (BALF) from rabbits exposed to diesel exhaust in order to find a useful biochemical indicator of the effects of diesel exhaust exposure on human health.

  3. Flare fragmentation and type III productivity in the 1980 June 27 flare

    NASA Technical Reports Server (NTRS)

    Aschwanden, M. J.; Schwartz, R. A.; Benz, A. O.; Lin, R. P.; Pelling, R. M.

    1990-01-01

    Observations of the solar flare on June 27, 1980 were presented, 16:14-16:33 UT, which was observed by a balloon-borne 300 sq cm phoswich hard X-ray detector and by the IKARUS radio spectrometer. This flare shows intense hard X-ray (HXR) emission and an extreme productivity of (at least 754) type III bursts at 200-400 MHz. A linear correlation was found between the type III burst rate and the HXR fluence. The occurrence of about 10 type III bursts/second, and also the even higher rate of millisecond spikes, suggests a high degree of fragmentation in the acceleration region. This high quantization of injected beams, assuming the thick-target model, shows up in a linear relationship between hard X-ray fluence and the type III rate, but not as fine structures in the HXR time profile. The generation of a superhot isothermal HXR component in the decay phase of the flare coincides with the fade-out of type III production.

  4. Linking insulin with Alzheimer's disease: emergence as type III diabetes.

    PubMed

    Ahmed, Sara; Mahmood, Zahra; Zahid, Saadia

    2015-10-01

    Alzheimer's disease (AD) has characteristic neuropathological abnormalities including regionalized neurodegeneration, neurofibrillary tangles, amyloid beta (Aβ) deposition, activation of pro-apoptotic genes, and oxidative stress. As the brain functions continue to disintegrate, there is a decline in person's cognitive abilities, memory, mood, spontaneity, and socializing behavior. A framework that sequentially interlinks all these phenomenons under one event is lacking. Accumulating evidence has indicated the role of insulin deficiency and insulin resistance as mediators of AD neurodegeneration. Herein, we reviewed the evidence stemming from the development of diabetes agent-induced AD animal model. Striking evidence has attributed loss of insulin receptor-bearing neurons to precede or accompany initial stage of AD. This state seems to progress with AD such that, in the terminal stages, it worsens and becomes global. Oxidative stress, tau hyperphosphorylation, APP-Aβ deposition, and impaired glucose and energy metabolism have all been linked to perturbation in insulin/IGF signaling. We conclude that AD could be referred to as "type 3 diabetes". Moreover, owing to common pathophysiology with diabetes common therapeutic regime could be effective for AD patients.

  5. An immunohistochemical and serum ELISA study of type I and III procollagen aminopropeptides in primary biliary cirrhosis.

    PubMed Central

    Davis, B. H.; Madri, J. A.

    1987-01-01

    By means of ELISA methodology, the aminopropeptides of Type I and Type III procollagen were measured in the serum of a group of patients with primary biliary cirrhosis. The corresponding liver biopsies were graded blindly for degrees of fibrosis and inflammation. When available, paraffin-embedded liver specimens underwent immunoperoxidase staining for mature Type I and III collagen as well as the aminopropeptides of Type I and III procollagen. Regardless of the degree of fibrosis or inflammation, serum levels of the aminopropeptide of Type I remained within normal limits. In contrast, serum levels of the aminopropeptide of Type III procollagen were elevated uniformly. Immunohistochemistry demonstrated that the aminopropeptide of Type III procollagen persists extracellularly. This finding may explain the previously reported relationship between levels of inflammation and serum levels of the Type III aminopropeptide. Images Figure 7 Figure 8 PMID:3303951

  6. Isolation and characterization of type III group B streptococcal mutants defective in biosynthesis of the type-specific antigen.

    PubMed Central

    Yeung, M K; Mattingly, S J

    1983-01-01

    Four classes of mutants of type III group B streptococcus were isolated by serial subculture of the wild-type strain in the presence of type III-specific rabbit antiserum. Class I mutants no longer synthesized sialic acid but still elaborated the core antigen. Class II mutants maintained the ability to synthesize sialic acid but could not attach it to the core antigen. Class III mutants did not produce the core antigen but still synthesized intracellular sialic acid. Class IV mutants synthesized the complete antigen; however, only approximately 4% of the antigen synthesized was found associated with the cell wall peptidoglycan (in the wild-type strain greater than 85% of the antigen synthesized is covalently attached to the cell wall peptidoglycan), whereas greater than 90% of the antigen was secreted into the growth medium. Production of other components (CAMP factor, group B antigen, beta-hemolysin, neuraminidase) by these mutants appeared similar to those of the wild-type strain. Mouse lethality studies of these strains indicated that all four classes have greater than 3 log10-higher 50% lethal dose values than that of the wild-type strain. To understand the basis for this variation, the invasive ability of the wild-type strain and the sialic acid-deficient mutant strain M-10 (class I) was examined. Mice received 10(5) CFU of each organism; they were then sacrificed at various times postinoculation, and viable group B streptococci from different organs were enumerated. Mice were able to clear M-10 more efficiently, with greater than 80% of M-10 cells being phagocytized by macrophages within 1 h, whereas the wild-type strain was able to evade phagocytic killing and disseminate to other tissues. These data, therefore, strongly indicate that the sialic acid moiety greatly enhances the virulence of the type III antigen. In addition, the level of cell-associated type-specific antigen appears to contribute significantly to the pathogenicity of the organism. PMID

  7. Laparoscopic Treatment of Type III Mirizzi Syndrome by T-Tube Drainage

    PubMed Central

    Yetışır, Fahri; Şarer, Akgün Ebru; Acar, H. Zafer; Polat, Yılmaz; Osmanoglu, Gokhan; Aygar, Muhittin; Ciftciler, A. Erdinc; Parlak, Omer

    2016-01-01

    Mirizzi syndrome (MS) is an impacted stone in the cystic duct or Hartmann's pouch that mechanically obstructs the common bile duct. We would like to report laparoscopic treatment of type III MS. A 75-year-old man was admitted with the complaint of abdominal pain and jaundice. The patient was accepted as MS type III according to radiological imaging and intraoperative view. Laparoscopic subtotal cholecystectomy, extraction of impacted stone by opening anterior surface of dilated cystic duct and choledochus, and repair of this opening by using the remaining part of gallbladder over the T-tube drainage were performed in a patient with type III MS. Application of reinforcement suture over stump was done in light of the checking with oliclinomel N4 injection trough the T-tube. At the 18-month follow-up, he was symptom-free with normal liver function tests. PMID:27293947

  8. Laparoscopic Treatment of Type III Mirizzi Syndrome by T-Tube Drainage.

    PubMed

    Yetışır, Fahri; Şarer, Akgün Ebru; Acar, H Zafer; Polat, Yılmaz; Osmanoglu, Gokhan; Aygar, Muhittin; Ciftciler, A Erdinc; Parlak, Omer

    2016-01-01

    Mirizzi syndrome (MS) is an impacted stone in the cystic duct or Hartmann's pouch that mechanically obstructs the common bile duct. We would like to report laparoscopic treatment of type III MS. A 75-year-old man was admitted with the complaint of abdominal pain and jaundice. The patient was accepted as MS type III according to radiological imaging and intraoperative view. Laparoscopic subtotal cholecystectomy, extraction of impacted stone by opening anterior surface of dilated cystic duct and choledochus, and repair of this opening by using the remaining part of gallbladder over the T-tube drainage were performed in a patient with type III MS. Application of reinforcement suture over stump was done in light of the checking with oliclinomel N4 injection trough the T-tube. At the 18-month follow-up, he was symptom-free with normal liver function tests. PMID:27293947

  9. Bartter syndrome type III and congenital anomalies of the kidney and urinary tract: an antenatal presentation.

    PubMed

    Westland, Rik; Hack, Wilfried W; van der Horst, Henricus J R; Uittenbogaard, Lukas B; van Hagen, Johanna M; van der Valk, Paul; Kamsteeg, Erik J; van den Heuvel, Lambert P; van Wijk, Joanna A E

    2012-12-01

    Bartter syndrome encompasses a variety of inheritable renal tubular transport disorders characterized by hypokalemia and hypochloremic metabolic alkalosis. Bartter syndrome Type III is caused by genetic alterations in the chloride channel kidney B (CLCNKB) gene and often presents in the first 2 years of life, known as classic Bartter syndrome. However, in rare cases Bartter syndrome Type III has an antenatal presentation with polyhydramnios, premature delivery and severe dehydration in the first weeks of life. Associations between congenital anomalies of the kidney and urinary tract and Bartter syndrome are extremely rare. This case report presents a girl with Bartter syndrome Type III due to a homozygous CLCNKB mutation and bilateral congenital anomalies of the kidney and urinary tract. In addition, we describe the antenatal presentation as well as its perinatal management.

  10. The heliocentric radial variation of plasma oscillations associated with type III radio bursts

    NASA Technical Reports Server (NTRS)

    Gurnett, D. A.; Anderson, R. R.; Scarf, F. L.; Kurth, W. S.

    1978-01-01

    A survey is presented of all of the electron plasma oscillation events found to date in association with low-frequency type III solar radio bursts using approximately 9 years of observations from the Imp 6 and 8, Helios 1 and 2, and Voyager 1 and 2 spacecraft. Plasma oscillation events associated with type III radio bursts show a pronounced increase in both the intensity and the frequency of occurrence with decreasing heliocentric radial distance. This radial dependence explains why intense electron plasma oscillations are seldon observed in association with type III radio bursts at the orbit of the earth. Possible interpretations of the observed radial variation in the plasma oscillation intensity are considered.

  11. Real-time imaging of type III secretion: Salmonella SipA injection into host cells.

    PubMed

    Schlumberger, Markus C; Müller, Andreas J; Ehrbar, Kristin; Winnen, Brit; Duss, Iwan; Stecher, Bärbel; Hardt, Wolf-Dietrich

    2005-08-30

    Many pathogenic and symbiotic Gram-negative bacteria employ type III secretion systems to inject "effector" proteins into eukaryotic host cells. These effectors manipulate signaling pathways to initiate symbiosis or disease. By using time-lapse microscopy, we have imaged delivery of the Salmonella type III effector protein SipA/SspA into animal cells in real time. SipA delivery mostly began 10-90 sec after docking and proceeded for 100-600 sec until the bacterial SipA pool (6 +/- 3 x 10(3) molecules) was exhausted. Similar observations were made for the effector protein SopE. This visualization of type III secretion in real time explains the efficiency of host cell manipulation by means of this virulence system. PMID:16107539

  12. Intestinal lymphangiectasia in a patient with autoimmune polyglandular syndrome type III.

    PubMed

    Choudhury, Bipul Kumar; Saiki, Uma Kaimal; Sarm, Dipti; Choudhury, Bikash Narayan; Choudhury, Sarojini Dutta; Saharia, Dhiren; Saikia, Mihir

    2011-11-01

    Autoimmune polyglandular syndromes (APS) comprise a wide clinical spectrum of autoimmune disorders. APS is divided into Type I, Type II, Type I and Type IV depending upon the pattern of disease combination. Ghronic diarrhoea is one of the many manifestations of APS and many aetiological factors have been suggested for it. Apart from the established aetiological factors, intestinal lymphangiectasia may be responsible for chronic diarrhea in some cases.Intestinal lymphangiectasia has been reported in Type I APS. We report a case of Type III APS with hypocalcaemia and hypothyroidism who had chronic diarrhea of long duration and was finally diagnosed to have intestinal lymphangiectasia. PMID:22616341

  13. Structure and Interactions of Fish Type III Antifreeze Protein in Solution

    PubMed Central

    Salvay, Andrés G.; Gabel, Frank; Pucci, Bernard; Santos, Javier; Howard, Eduardo I.; Ebel, Christine

    2010-01-01

    Abstract It has been suggested that above a critical protein concentration, fish Type III antifreeze protein (AFP III) self-assembles to form micelle-like structures that may play a key role in antifreeze activity. To understand the complex activity of AFP III, a comprehensive description of its association state and structural organization in solution is necessary. We used analytical ultracentrifugation, analytical size-exclusion chromatography, and dynamic light scattering to characterize the interactions and homogeneity of AFP III in solution. Small-angle neutron scattering was used to determine the low-resolution structure in solution. Our results clearly show that at concentrations up to 20 mg mL−1 and at temperatures of 20°C, 6°C, and 4°C, AFP III is monomeric in solution and adopts a structure compatible with that determined by crystallography. Surface tension measurements show a propensity of AFP III to localize at the air/water interface, but this surface activity is not correlated with any aggregation in the bulk. These results support the hypothesis that each AFP III molecule acts independently of the others, and that specific intermolecular interactions between monomers are not required for binding to ice. The lack of attractive interactions between monomers may be functionally important, allowing for more efficient binding and covering of the ice surface. PMID:20643081

  14. Structure and interactions of fish type III antifreeze protein in solution.

    PubMed

    Salvay, Andrés G; Gabel, Frank; Pucci, Bernard; Santos, Javier; Howard, Eduardo I; Ebel, Christine

    2010-07-21

    It has been suggested that above a critical protein concentration, fish Type III antifreeze protein (AFP III) self-assembles to form micelle-like structures that may play a key role in antifreeze activity. To understand the complex activity of AFP III, a comprehensive description of its association state and structural organization in solution is necessary. We used analytical ultracentrifugation, analytical size-exclusion chromatography, and dynamic light scattering to characterize the interactions and homogeneity of AFP III in solution. Small-angle neutron scattering was used to determine the low-resolution structure in solution. Our results clearly show that at concentrations up to 20 mg mL(-1) and at temperatures of 20 degrees C, 6 degrees C, and 4 degrees C, AFP III is monomeric in solution and adopts a structure compatible with that determined by crystallography. Surface tension measurements show a propensity of AFP III to localize at the air/water interface, but this surface activity is not correlated with any aggregation in the bulk. These results support the hypothesis that each AFP III molecule acts independently of the others, and that specific intermolecular interactions between monomers are not required for binding to ice. The lack of attractive interactions between monomers may be functionally important, allowing for more efficient binding and covering of the ice surface.

  15. Electron Exciter Speeds Associated with Interplanetary Type III Solar Radio Bursts

    NASA Astrophysics Data System (ADS)

    Reiner, M. J.; MacDowall, R. J.

    2015-10-01

    This article provides a comprehensive quantitative investigation of the kinematics of the electron exciters associated with interplanetary type III solar radio bursts. Detailed multispacecraft analyses of the radio and plasma wave data from the widely separated Wind and STEREO spacecraft are provided for five interplanetary type III bursts that illustrate different aspects of the problems involved in establishing the electron exciter speeds. The exciter kinematics are determined from the observed frequency drift and in-situ radiation characteristics for each type III burst. The analysis assumes propagation of the electron exciters along a Parker spiral, with origin at the associated solar active region, and curvature determined by the measured solar wind speed. The analyses take fully into account the appropriate light-propagation-time corrections from the radio source to the observing spacecraft as the exciters propagate along the Parker spiral path. For the five in-situ type III bursts analyzed in detail here, we found that their initial exciter speeds, near the Sun, ranged from 0.2c to 0.38c, where c is the speed of light. This is significantly higher than the exciter speeds derived from other recent analyses. The results presented here further suggest that the type III electron exciters normally decelerate as they propagate through the interplanetary medium. We argue based on the observations by the widely separated spacecraft that the initial part of the type III radiation usually occurs at the fundamental of the plasma frequency. Finally, we compare the results for the exciter speeds to all previous determinations and provide quantitative arguments to explain the differences.

  16. Proteolytic Processing of Neuregulin 1 Type III by Three Intramembrane-cleaving Proteases.

    PubMed

    Fleck, Daniel; Voss, Matthias; Brankatschk, Ben; Giudici, Camilla; Hampel, Heike; Schwenk, Benjamin; Edbauer, Dieter; Fukumori, Akio; Steiner, Harald; Kremmer, Elisabeth; Haug-Kröper, Martina; Rossner, Moritz J; Fluhrer, Regina; Willem, Michael; Haass, Christian

    2016-01-01

    Numerous membrane-bound proteins undergo regulated intramembrane proteolysis. Regulated intramembrane proteolysis is initiated by shedding, and the remaining stubs are further processed by intramembrane-cleaving proteases (I-CLiPs). Neuregulin 1 type III (NRG1 type III) is a major physiological substrate of β-secretase (β-site amyloid precursor protein-cleaving enzyme 1 (BACE1)). BACE1-mediated cleavage is required to allow signaling of NRG1 type III. Because of the hairpin nature of NRG1 type III, two membrane-bound stubs with a type 1 and a type 2 orientation are generated by proteolytic processing. We demonstrate that these stubs are substrates for three I-CLiPs. The type 1-oriented stub is further cleaved by γ-secretase at an ϵ-like site five amino acids N-terminal to the C-terminal membrane anchor and at a γ-like site in the middle of the transmembrane domain. The ϵ-cleavage site is only one amino acid N-terminal to a Val/Leu substitution associated with schizophrenia. The mutation reduces generation of the NRG1 type III β-peptide as well as reverses signaling. Moreover, it affects the cleavage precision of γ-secretase at the γ-site similar to certain Alzheimer disease-associated mutations within the amyloid precursor protein. The type 2-oriented membrane-retained stub of NRG1 type III is further processed by signal peptide peptidase-like proteases SPPL2a and SPPL2b. Expression of catalytically inactive aspartate mutations as well as treatment with 2,2'-(2-oxo-1,3-propanediyl)bis[(phenylmethoxy)carbonyl]-l-leucyl-l-leucinamide ketone inhibits formation of N-terminal intracellular domains and the corresponding secreted C-peptide. Thus, NRG1 type III is the first protein substrate that is not only cleaved by multiple sheddases but is also processed by three different I-CLiPs. PMID:26574544

  17. Sphincter of Oddi dysfunction Type III: New studies suggest new approaches are needed

    PubMed Central

    Wilcox, C Mel

    2015-01-01

    Sphincter of Oddi dysfunction (SOD) has been classified into three types based upon the presence or absence of objective findings including liver test abnormalities and bile duct dilatation. Type III is the most controversial and is classified as biliary type pain in the absence of any these objective findings. Many prior studies have shown that the clinical response to endoscopic therapy is higher based upon the presence of these objective criteria. However, there has been variable correlation of the manometry findings to outcome after endoscopic therapy. Nevertheless, manometry and sphincterotomy has been recommended for Type III patients given the overall response rate of 33%, although the reported response rates are highly variable. However, all of the prior data was non-blinded and non-randomized with variable follow-up. The evaluating predictors in SOD study - a prospective randomized blinded sham controlled one year outcome study showed no correlation between manometric findings and outcome after sphincterotomy. Furthermore, patients receiving sham therapy had a statistically significantly better outcome than those undergoing biliary or dual sphincterotomy. This study calls into question the whole concept of SOD Type III and, based upon prior physiologic studies, one can suggest that SOD Type III likely represents a right upper quadrant functional abdominal pain syndrome and should be treated as such. PMID:26019439

  18. Conservative Management of Type III Dens in Dente Using Cone Beam Computed Tomography

    PubMed Central

    Pradeep, K.; Charlie, M.; Kuttappa, M. A.; Rao, Prasana Kumar

    2012-01-01

    Dens in dente, also known as dens invaginatus, dilated composite odontoma, or deep foramen caecum, is a developmental malformation that usually affects maxillary incisor teeth, particularly lateral incisors. It may occur in teeth anywhere within the jaws, other locations are comparatively rare. It can occur within both the crown and the root, although crown invaginations are more common. The use of cone beam computed tomography (CBCT) is very helpful in endodontic diagnosis of complex anatomic variations. In this case we demonstrate the use of CBCT in the evaluation and endodontic management of a Type III dens in dente (Oehler's Type III). PMID:23029634

  19. [Advances in studies of the type III secretion system in Ralstonia solanacearum--A review].

    PubMed

    Zhang, Yong; Li, Muyuan; Luo, Feng

    2015-06-01

    Bacterial wilt caused by Ralstonia solanacearum is one of the most devastating plant diseases worldwide. The syringe-like type III secretion system (T3SS) plays a crucial role in its pathogenicity. R. solanacearum uses the T3SS to inject effector proteins (Type III effectors) into the cytoplasm of host cells, causing diseases in susceptible plants or triggering the hypersensitive response in resistant plants. In this article we review recent advances in studies of R. solanacearum T3SS and highlight their unique features. PMID:26562991

  20. Solar wind density model from km-wave type III bursts.

    NASA Technical Reports Server (NTRS)

    Alvarez, H.; Haddock, F. T.

    1973-01-01

    The analysis of type III bursts observed from the OGO-5 satellite between 3.5 MHz and 50 kHz gives an empirical expression for the frequency drift rate as a function of frequency that is valid from 75 kHz to 550 MHz. Using this expression and some simplifying assumptions we obtain indirectly an empirical formula for the electron density distribution of the solar wind to 1 AU which is consistent with published values of electron density and with observed type III burst drift rates.

  1. Crystal structure of the Yersinia type III secretion protein YscE

    SciTech Connect

    Phan, Jason; Austin, Brian P.; Waugh, David S.

    2010-12-06

    The plague-causing bacterium Yersinia pestis utilizes a contact-dependent (type III) secretion system (T3SS) to transport virulence factors from the bacterial cytosol directly into the interior of mammalian cells where they interfere with signal transduction pathways that mediate phagocytosis and the inflammatory response. The type III secretion apparatus is composed of 20-25 different Yersinia secretion (Ysc) proteins. We report here the structure of YscE, the smallest Ysc protein, which is a dimer in solution. The probable mode of oligomerization is discussed.

  2. Enzymatic synthesis of bis-5-alkylresorcinols by resorcinol-producing type III polyketide synthases.

    PubMed

    Miyanaga, Akimasa; Horinouchi, Sueharu

    2009-07-01

    No enzyme systems responsible for the biosynthesis of structurally and biosynthetically intriguing bis-5-alkylresorcinols produced by plants have been identified. Herein, we show that bacterial, fungal and plant alkylresorcinol-producing type III polyketide synthases (PKSs), such as ArsB in the Gram-negative bacterium Azotobacter vinelandii, ORAS in the fungus Neurospora crassa and ARAS2 in the rice plant Oryza sativa, can synthesize bis-5-alkylresorcinol from alkanedioic acid N-acetylcysteamine dithioester as a starter substrate and from malonyl-CoA as an extender substrate by two-step conversion. Plants presumably use a type III PKS for the biosynthesis of bis-5-alkylresorcinols.

  3. Solar longitude dependence of some characteristics of type III radio bursts from metric to hectometric wavelengths

    NASA Technical Reports Server (NTRS)

    Sakurai, K.

    1974-01-01

    Using the observed data for metric and hectometric type III radio bursts, the dependence of burst characteristics on the solar longitude has been examined over a wide frequency range. It is found that there exists and east-west asymmetry for the extension of metric type III bursts into the hectometric wavelength range. In particular, hectometric bursts are rarely observed for solar flares associated with metric bursts east of 60 E solar longitude. Furthermore, for east longitudes, the low-frequency radio observations show a large dispersion in drift time interval.

  4. Vlasov simulations of Langmuir Electrostatic Decay and consequences for Type III observations

    SciTech Connect

    Henri, P.; Califano, F.; Briand, C.; Mangeney, A.

    2010-03-25

    The electrostatic decay enables energy transfer from a finite amplitude Langmuir to a backscattered daughter Langmuir wave and ion acoustic density fluctuations. This mechanism is thought to be a first step for the generation of type III solar radio emissions at twice the plasma frequency. The electrostatic decay is here investigated through Vlasov-Poisson simulations by considering Langmuir localized wave packets in the case T{sub e} = T{sub p}. Simulation results are found to be in good agreement with recently reported observations from the STEREO mission of the electrostatic decay of beam-driven Langmuir waves during a type III burst.

  5. [Advances in studies of the type III secretion system in Ralstonia solanacearum--A review].

    PubMed

    Zhang, Yong; Li, Muyuan; Luo, Feng

    2015-06-01

    Bacterial wilt caused by Ralstonia solanacearum is one of the most devastating plant diseases worldwide. The syringe-like type III secretion system (T3SS) plays a crucial role in its pathogenicity. R. solanacearum uses the T3SS to inject effector proteins (Type III effectors) into the cytoplasm of host cells, causing diseases in susceptible plants or triggering the hypersensitive response in resistant plants. In this article we review recent advances in studies of R. solanacearum T3SS and highlight their unique features.

  6. Three cross leg flaps for lower leg reconstruction of Gustilo type III C open fracture

    PubMed Central

    Sano, Kazufumi; Ozeki, Satoru; Sugimoto, Ichiro; Ogawa, Masato

    2016-01-01

    A 60 year old male had Gustilo type III C open fracture of the right lower leg. After radical debridement, the large open defect including certain loss of the bone tissue was successfully augmented and covered, by consecutive three cross-leg flaps, which consisted of the free rectus abdominis musculocutaneous flap, the fibula osteocutaneous flap and the conventional sural flap. Although indication for amputation or preservation is decided with multiple factors in each case, a strategic combination of cross-leg flap, free flap, external fixation and vascular delay could increase the potential of preservation of the lower leg with even disastrous Gustilo type III C. PMID:27293297

  7. Dielectric properties of I-III-VI2-type chalcopyrite semiconductors

    NASA Astrophysics Data System (ADS)

    Xue, D.; Betzler, K.; Hesse, H.

    2000-11-01

    Dielectric properties of I-III-VI2-type ternary chalcopyrite semiconductors, including linear and second order nonlinear optical susceptibilities at 10.6 μm, have been quantitatively studied from the chemical bond viewpoint. Contributions from each type of constituent chemical bond, i.e., I - VI and III - VI bonds, to the total linear and nonlinear optical properties of these compounds at 10.6 μm have been theoretically determined. The chemical bond method quantitatively expresses the trends in the dielectric properties of these compounds, which is helpful for carrying out modeling of their properties.

  8. YopR impacts type III needle polymerization in Yersinia species

    PubMed Central

    Blaylock, Bill; Berube, Bryan J.; Schneewind, Olaf

    2010-01-01

    Summary A hallmark of Yersinia type III machines is the presence of needles extending from the bacterial surface. Needles perform two functions, serving as the conduits for the transport of effectors into immune cells but also acting as a sensor. The polymerized needle protein, YscF, is thought to perceive threshold levels of environmental calcium ions to trigger secretion. yopR (yscH) is a gene downstream of yscEFG, encoding the chaperones and principal building blocks of the needle. Here we investigated the contribution of YopR towards type III secretion and pathogenesis. Yersinia pestis KIM D27 mutants lacking yopR were defective for virulence in a mouse model of septicemic plague. yopR variants of Yersinia enterocolitica W22703 displayed a reduced ability to inject effectors into macrophages and required lower calcium concentrations to activate type III secretion than wild-type yersiniae. Further, yopR mutants failed to assemble YscF into needle complexes and instead secreted YscF into the medium. These results imply that YopR may be involved in controlling the secretion of YscF, thereby impacting the assembly of type III machines. An alternative possibility, that YopR participates directly in the polymerization of YscF, seems less likely as YopR is not associated with purified needles. PMID:19968786

  9. Structure, Evolution, and Functions of Bacterial Type III Toxin-Antitoxin Systems

    PubMed Central

    Goeders, Nathalie; Chai, Ray; Chen, Bihe; Day, Andrew; Salmond, George P. C.

    2016-01-01

    Toxin-antitoxin (TA) systems are small genetic modules that encode a toxin (that targets an essential cellular process) and an antitoxin that neutralises or suppresses the deleterious effect of the toxin. Based on the molecular nature of the toxin and antitoxin components, TA systems are categorised into different types. Type III TA systems, the focus of this review, are composed of a toxic endoribonuclease neutralised by a non-coding RNA antitoxin in a pseudoknotted configuration. Bioinformatic analysis shows that the Type III systems can be classified into subtypes. These TA systems were originally discovered through a phage resistance phenotype arising due to a process akin to an altruistic suicide; the phenomenon of abortive infection. Some Type III TA systems are bifunctional and can stabilise plasmids during vegetative growth and sporulation. Features particular to Type III systems are explored here, emphasising some of the characteristics of the RNA antitoxin and how these may affect the co-evolutionary relationship between toxins and cognate antitoxins in their quaternary structures. Finally, an updated analysis of the distribution and diversity of these systems are presented and discussed. PMID:27690100

  10. Novel findings in patients with primary hyperoxaluria type III and implications for advanced molecular testing strategies.

    PubMed

    Beck, Bodo B; Baasner, Anne; Buescher, Anja; Habbig, Sandra; Reintjes, Nadine; Kemper, Markus J; Sikora, Przemyslaw; Mache, Christoph; Pohl, Martin; Stahl, Mirjam; Toenshoff, Burkhard; Pape, Lars; Fehrenbach, Henry; Jacob, Dorrit E; Grohe, Bernd; Wolf, Matthias T; Nürnberg, Gudrun; Yigit, Gökhan; Salido, Eduardo C; Hoppe, Bernd

    2013-02-01

    Identification of mutations in the HOGA1 gene as the cause of autosomal recessive primary hyperoxaluria (PH) type III has revitalized research in the field of PH and related stone disease. In contrast to the well-characterized entities of PH type I and type II, the pathophysiology and prevalence of type III is largely unknown. In this study, we analyzed a large cohort of subjects previously tested negative for type I/II by complete HOGA1 sequencing. Seven distinct mutations, among them four novel, were found in 15 patients. In patients of non-consanguineous European descent the previously reported c.700+5G>T splice-site mutation was predominant and represents a potential founder mutation, while in consanguineous families private homozygous mutations were identified throughout the gene. Furthermore, we identified a family where a homozygous mutation in HOGA1 (p.P190L) segregated in two siblings with an additional AGXT mutation (p.D201E). The two girls exhibiting triallelic inheritance presented a more severe phenotype than their only mildly affected p.P190L homozygous father. In silico analysis of five mutations reveals that HOGA1 deficiency is causing type III, yet reduced HOGA1 expression or aberrant subcellular protein targeting is unlikely to be the responsible pathomechanism. Our results strongly suggest HOGA1 as a major cause of PH, indicate a greater genetic heterogeneity of hyperoxaluria, and point to a favorable outcome of type III in the context of PH despite incomplete or absent biochemical remission. Multiallelic inheritance could have implications for genetic testing strategies and might represent an unrecognized mechanism for phenotype variability in PH.

  11. Tracking Type III Radio Burst Sources in the Solar Corona by Heliographic Means

    NASA Astrophysics Data System (ADS)

    Koval, A. A.; Stanislavsky, A. A.; Konovalenko, A. A.; Volvach, Ya. S.

    We present the preliminary results of heliographic measurements of solar type III radio bursts in the low-frequency range (16.5-33 MHz) using the UTR-2 radio heliograph. The radio astronomy tools permit us to obtain two-dimensional spatial structures of burst sources in dependence of frequency and time. Each heliogram consists of 40 pixels (beams) as a result of the serial sweep in UV-plane wherein signals of each beam are recorded in a dynamic spectrum with both high temporal (˜ 2.482 ms) and top spectral (˜ 4 kHz) resolutions. The rate of output heliograph is one image per 3 seconds. Over a session in April, 2013 many type III radio and IIIb-III bursts were observed. On the heliograms the source motion direction in the upper corona is clearly detectable. The heliogram features are discussed.

  12. Plasma ApoC-III Levels, Triglycerides, and Coronary Artery Calcification in Type 2 Diabetics

    PubMed Central

    Qamar, Arman; Khetarpal, Sumeet A.; Khera, Amit V.; Qasim, Atif; Rader, Daniel J.; Reilly, Muredach P.

    2015-01-01

    Objective Triglyceride-rich lipoproteins (TRL) have emerged as causal risk factors for developing coronary heart disease (CHD) independent of low-density lipoprotein cholesterol (LDL-C) levels. Apolipoprotein C-III (ApoC-III) modulates TRL metabolism through inhibition of lipoprotein lipase and hepatic uptake of TRL. Mutations causing loss-of-function of ApoC-III lower TG and reduce CHD risk, suggestive of a causal role for ApoC-III. Little data exist regarding the relationship of ApoC-III, TG, and atherosclerosis in type 2 diabetes mellitus (T2DM) patients. Here, we examined the relationships between plasma ApoC-III, TG and coronary artery calcification (CAC) in T2DM patients. Approach & Results Plasma ApoC-III levels were measured in a cross-sectional study of 1422 subjects with T2DM but without clinically manifest CHD. ApoC-III levels were positively associated with total cholesterol (Spearman r=0.36), TG (r=0.59), LDL-C (r=0.16), fasting glucose (r=0.16) and glycosylated hemoglobin (r=0.12) (P < 0.0001 for all). In age, gender, and race-adjusted analysis, ApoC-III levels were positively associated with CAC (Tobit regression ratio (TRR) 1.78, 95% CI 1.27–2.50 per SD-increase in ApoC-III, P <0.001). As expected for an intermediate mediator, these findings were attenuated when adjusted for both TG (TRR 1.43, 95% CI 0.94–2.18, P=0.086) and separately for VLDL-C (TRR 1.14, 95% ci 0.75–1.71, P=0.53). Conclusions In persons with T2DM, increased plasma ApoC-III is associated with higher TG, less favorable cardiometabolic phenotypes, and higher CAC, a measure of subclinical atherosclerosis. Therapeutic inhibition of ApoC-III may thus be a novel strategy for reducing plasma TRLs and cardiovascular risk in T2DM. PMID:26069232

  13. Type III interferon gene expression in response to influenza virus infection in chicken and duck embryonic fibroblasts.

    PubMed

    Zhang, Zhijie; Zou, Tingting; Hu, Xiaotong; Jin, Hong

    2015-12-01

    Type III interferons (IFN-λs) comprise a group of newly identified antiviral cytokines that are functionally similar to type I IFNs and elicit first-line antiviral responses. Recently, type III IFNs were identified in several species; however, little information is available about type III IFNs in ducks. We compared the expression of type III IFNs and their receptor in chicken embryonic fibroblasts (CEFs) and duck embryonic fibroblasts (DEFs) in response to influenza virus infection. The results showed that the expression of type III IFNs was upregulated in both DEFs and CEFs following infection with H1N1 influenza virus or treatment with poly (I:C), and expression levels were significantly higher in CEFs than in DEFs at each time point. The expression of the receptor for type III IFNs (IL-28Rα) was also upregulated following infection with H1N1 virus or treatment with poly (I:C) and was significantly higher in CEFs than in DEFs at each time point. The expression of the receptor for type III IFNs occurred from 8 hpi and remained at similar levels until 36 hpi in CEFs, but the expression level was elevated from 36 hpi in DEFs. These findings revealed the existence of distinct expression patterns for type III IFNs in chickens and ducks in response to influenza virus infection. The provided data are fundamentally useful in furthering our understanding of type III IFNs and innate antiviral responses in different species.

  14. Type III interferon gene expression in response to influenza virus infection in chicken and duck embryonic fibroblasts.

    PubMed

    Zhang, Zhijie; Zou, Tingting; Hu, Xiaotong; Jin, Hong

    2015-12-01

    Type III interferons (IFN-λs) comprise a group of newly identified antiviral cytokines that are functionally similar to type I IFNs and elicit first-line antiviral responses. Recently, type III IFNs were identified in several species; however, little information is available about type III IFNs in ducks. We compared the expression of type III IFNs and their receptor in chicken embryonic fibroblasts (CEFs) and duck embryonic fibroblasts (DEFs) in response to influenza virus infection. The results showed that the expression of type III IFNs was upregulated in both DEFs and CEFs following infection with H1N1 influenza virus or treatment with poly (I:C), and expression levels were significantly higher in CEFs than in DEFs at each time point. The expression of the receptor for type III IFNs (IL-28Rα) was also upregulated following infection with H1N1 virus or treatment with poly (I:C) and was significantly higher in CEFs than in DEFs at each time point. The expression of the receptor for type III IFNs occurred from 8 hpi and remained at similar levels until 36 hpi in CEFs, but the expression level was elevated from 36 hpi in DEFs. These findings revealed the existence of distinct expression patterns for type III IFNs in chickens and ducks in response to influenza virus infection. The provided data are fundamentally useful in furthering our understanding of type III IFNs and innate antiviral responses in different species. PMID:26598110

  15. Biosynthesis of Dictyostelium discoideum differentiation-inducing factor by a hybrid type I fatty acid-type III polyketide synthase.

    PubMed

    Austin, Michael B; Saito, Tamao; Bowman, Marianne E; Haydock, Stephen; Kato, Atsushi; Moore, Bradley S; Kay, Robert R; Noel, Joseph P

    2006-09-01

    Differentiation-inducing factors (DIFs) are well known to modulate formation of distinct communal cell types from identical Dictyostelium discoideum amoebas, but DIF biosynthesis remains obscure. We report complimentary in vivo and in vitro experiments identifying one of two approximately 3,000-residue D. discoideum proteins, termed 'steely', as responsible for biosynthesis of the DIF acylphloroglucinol scaffold. Steely proteins possess six catalytic domains homologous to metazoan type I fatty acid synthases (FASs) but feature an iterative type III polyketide synthase (PKS) in place of the expected FAS C-terminal thioesterase used to off load fatty acid products. This new domain arrangement likely facilitates covalent transfer of steely N-terminal acyl products directly to the C-terminal type III PKS active sites, which catalyze both iterative polyketide extension and cyclization. The crystal structure of a steely C-terminal domain confirms conservation of the homodimeric type III PKS fold. These findings suggest new bioengineering strategies for expanding the scope of fatty acid and polyketide biosynthesis. PMID:16906151

  16. Decameter Type III Bursts with Changing Frequency Drift-Rate Signs

    NASA Astrophysics Data System (ADS)

    Melnik, V. N.; Brazhenko, A. I.; Konovalenko, A. A.; Briand, C.; Dorovskyy, V. V.; Zarka, P.; Frantsuzenko, A. V.; Rucker, H. O.; Rutkevych, B. P.; Panchenko, M.; Denis, L.; Zaqarashvili, T.; Shergelashvili, B.

    2015-01-01

    We discuss properties of type III bursts that change the sign of their drift rate from negative to positive and vice versa. Moreover, these bursts may change the sign of their drift rates more than once. These particular type III bursts were observed simultaneously by the radio telescopes UTR-2 ( Ukrainian T-shaped Radio telescope, Kharkov, Ukraine), URAN-2 ( Ukrainian Radio telescope of the Academy of Sciences, Poltava, Ukraine), and by the NDA ( Nançay Decametric Array, Nancay, France) in the frequency range 8 - 41 MHz. The negative drift rates of these bursts are similar to those of previously reported decameter type III bursts and vary from -0.7 MHz s-1 to -1.7 MHz s-1, but their positive drift rates vary in a wider range from 0.44 MHz s-1 to 6 MHz s-1. Unlike inverted U-bursts, the tracks of these type III bursts have C- or inverted C-shapes.

  17. The Type III Secretion System Cleans up Its Act(in).

    PubMed

    Auerbuch, Victoria

    2016-09-14

    Inflammasome-associated innate immune receptors sense host-cell targeting by the type III secretion system (T3SS) of pathogenic Yersinia. In this issue of Cell Host & Microbe, Chung et al. (2016) show that the Yersinia T3SS effector protein YopM counteracts this recognition pathway by restricting the pyrin inflammasome, thus increasing bacterial fitness.

  18. The Type III Secretion System Cleans up Its Act(in).

    PubMed

    Auerbuch, Victoria

    2016-09-14

    Inflammasome-associated innate immune receptors sense host-cell targeting by the type III secretion system (T3SS) of pathogenic Yersinia. In this issue of Cell Host & Microbe, Chung et al. (2016) show that the Yersinia T3SS effector protein YopM counteracts this recognition pathway by restricting the pyrin inflammasome, thus increasing bacterial fitness. PMID:27631695

  19. A Bacterial Pathogen uses Distinct Type III Secretion Systems to Alternate between Host Kingdom

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gram-negative bacterial pathogens of eukaryotes often secrete proteins directly into host cells via a needle-like protein channel called a ‘type III secretion system’ (T3SS). Bacteria that are adapted to either animal or plant hosts use phylogenetically distinct T3SSs for secreting proteins. Here, ...

  20. 33 CFR 159.12a - Certification of certain Type III devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Certification of certain Type III devices. 159.12a Section 159.12a Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Certification Procedures § 159.12a...

  1. 33 CFR 159.12a - Certification of certain Type III devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Certification of certain Type III devices. 159.12a Section 159.12a Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Certification Procedures § 159.12a...

  2. Mutations in the 4-hydroxyphenylpyruvic acid dioxygenase gene are responsible for tyrosinemia type III and hawkinsinuria.

    PubMed

    Tomoeda, K; Awata, H; Matsuura, T; Matsuda, I; Ploechl, E; Milovac, T; Boneh, A; Scott, C R; Danks, D M; Endo, F

    2000-11-01

    The enzyme 4-hydroxyphenylpyruvic acid dioxygenase (HPD) catalyzes the reaction of 4-hydroxyphenylpyruvic acid to homogentisic acid in the tyrosine catabolism pathway. A deficiency in the catalytic activity of HPD may lead to tyrosinemia type III, an autosomal recessive disorder characterized by elevated levels of blood tyrosine and massive excretion of tyrosine derivatives into urine. It has been postulated that hawkinsinuria, an autosomal dominant disorder characterized by the excretion of 'hawkinsin,' may also be a result of HPD deficiency. Hawkinsin is a sulfur amino acid identified as (2-l-cystein-S-yl, 4-dihydroxycyclohex-5-en-1-yl)acetic acid. Patients with hawkinsinuria excrete this metabolite in their urine throughout their life, although symptoms of metabolic acidosis and tyrosinemia improve in the first year of life. We performed analyses of the HPD gene in a patient with tyrosinemia type III and two unrelated patients with hawkinsinuria. A homozygous missense mutation predicting an Ala to Val change at codon 268 (A268V) in the HPD gene was found in the patient with tyrosinemia type III. A heterozygous missense mutation predicting an Ala to Thr change at codon 33 (A33T) was found in the same HPD gene in the two patients with hawkinsinuria. These findings support the hypothesis that alterations in the structure and activity of HPD are causally related to two different metabolic disorders, tyrosinemia type III and hawkinsinuria.

  3. Propolis Modifies Collagen Types I and III Accumulation in the Matrix of Burnt Tissue

    PubMed Central

    Olczyk, Pawel; Wisowski, Grzegorz; Komosinska-Vassev, Katarzyna; Stojko, Jerzy; Klimek, Katarzyna; Olczyk, Monika; Kozma, Ewa M.

    2013-01-01

    Wound healing represents an interactive process which requires highly organized activity of various cells, synthesizing cytokines, growth factors, and collagen. Collagen types I and III, serving as structural and regulatory molecules, play pivotal roles during wound healing. The aim of this study was to compare the propolis and silver sulfadiazine therapeutic efficacy throughout the quantitative and qualitative assessment of collagen types I and III accumulation in the matrix of burnt tissues. Burn wounds were inflicted on pigs, chosen for the evaluation of wound repair because of many similarities between pig and human skin. Isolated collagen types I and III were estimated by the surface plasmon resonance method with a subsequent collagenous quantification using electrophoretic and densitometric analyses. Propolis burn treatment led to enhanced collagens and its components expression, especially during the initial stage of the study. Less expressed changes were observed after silver sulfadiazine (AgSD) application. AgSD and, with a smaller intensity, propolis stimulated accumulation of collagenous degradation products. The assessed propolis therapeutic efficacy, throughout quantitatively and qualitatively analyses of collagen types I and III expression and degradation in wounds matrix, may indicate that apitherapeutic agent can generate favorable biochemical environment supporting reepithelization. PMID:23781260

  4. The Chlamydial Type III Secretion Mechanism: Revealing Cracks in a Tough Nut

    PubMed Central

    Betts-Hampikian, Helen Jennifer; Fields, Kenneth A.

    2010-01-01

    Present-day members of the Chlamydiaceae contain parasitic bacteria that have been co-evolving with their eukaryotic hosts over hundreds of millions of years. Likewise, a type III secretion system encoded within all genomes has been refined to complement the unique obligate intracellular niche colonized so successfully by Chlamydia spp. All this adaptation has occurred in the apparent absence of the horizontal gene transfer responsible for creating the wide range of diversity in other Gram-negative, type III-expressing bacteria. The result is a system that is, in many ways, uniquely chlamydial. A critical mass of information has been amassed that sheds significant light on how the chlamydial secretion system functions and contributes to an obligate intracellular lifestyle. Although the overall mechanism is certainly similar to homologous systems, an image has emerged where the chlamydial secretion system is essential for both survival and virulence. Numerous apparent differences, some subtle and some profound, differentiate chlamydial type III secretion from others. Herein, we provide a comprehensive review of the current state of knowledge regarding the Chlamydia type III secretion mechanism. We focus on the aspects that are distinctly chlamydial and comment on how this important system influences chlamydial pathogenesis. Gaining a grasp on this fascinating system has been challenging in the absence of a tractable genetic system. However, the surface of this tough nut has been scored and the future promises to be fruitful and revealing. PMID:21738522

  5. Molecular mechanisms of bacterial virulence: type III secretion and pathogenicity islands.

    PubMed

    Mecsas, J J; Strauss, E J

    1996-01-01

    Recently, two novel but widespread themes have emerged in the field of bacterial virulence: type III secretion systems and pathogenicity islands. Type III secretion systems, which are found in various gram-negative organisms, are specialized for the export of virulence factors delivered directly to host cells. These factors subvert normal host cell functions in ways that seem beneficial to invading bacteria. The genes encoding several type III secretion systems reside on pathogenicity islands, which are inserted DNA segments within the chromosome that confer upon the host bacterium a variety of virulence traits, such as the ability to acquire iron and to adhere to or enter host cells. Many of these segments of DNA appear to have been acquired in a single step from a foreign source. The ability to obtain complex virulence traits in one genetic event, rather than by undergoing natural selection for many generations, provides a mechanism for sudden radical changes in bacterial-host interactions. Type III secretion systems and pathogenicity islands must have played critical roles in the evolution of known pathogens and are likely to lead to the emergence of novel infectious diseases in the future.

  6. On the speed and acceleration of electron beams triggering interplanetary type III radio bursts

    NASA Astrophysics Data System (ADS)

    Krupar, V.; Kontar, E. P.; Soucek, J.; Santolik, O.; Maksimovic, M.; Kruparova, O.

    2015-08-01

    Aims: Type III radio bursts are intense radio emissions triggered by beams of energetic electrons often associated with solar flares. These exciter beams propagate outwards from the Sun along an open magnetic field line in the corona and in the interplanetary (IP) medium. Methods: We performed a statistical survey of 29 simple and isolated IP type III bursts observed by STEREO/Waves instruments between January 2013 and September 2014. We investigated their time-frequency profiles in order to derive the speed and acceleration of exciter electron beams. Results: We show these beams noticeably decelerate in the IP medium. Obtained speeds range from ~0.02c up to ~0.35c depending on initial assumptions. It corresponds to electron energies between tens of eV and hundreds of keV, and in order to explain the characteristic energies or speeds of type III electrons (~0.1c) observed simultaneously with Langmuir waves at 1 au, the emission of type III bursts near the peak should be predominately at double plasma frequency. Derived properties of electron beams can be used as input parameters for computer simulations of interactions between the beam and the plasma in the IP medium. Appendix A is available in electronic form at http://www.aanda.org

  7. A bacterial pathogen uses distinct type III secretion systems to alternate between host kingdoms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant and animal-pathogenic bacteria utilize phylogenetically distinct type III secretion systems (T3SS) that produce needle-like injectisomes or pili for the delivery of effector proteins into host cells. Pantoea stewartii subsp. stewartii (Pnss), the causative agent of Stewart’s bacterial wilt and...

  8. Propolis Modifies Collagen Types I and III Accumulation in the Matrix of Burnt Tissue.

    PubMed

    Olczyk, Pawel; Wisowski, Grzegorz; Komosinska-Vassev, Katarzyna; Stojko, Jerzy; Klimek, Katarzyna; Olczyk, Monika; Kozma, Ewa M

    2013-01-01

    Wound healing represents an interactive process which requires highly organized activity of various cells, synthesizing cytokines, growth factors, and collagen. Collagen types I and III, serving as structural and regulatory molecules, play pivotal roles during wound healing. The aim of this study was to compare the propolis and silver sulfadiazine therapeutic efficacy throughout the quantitative and qualitative assessment of collagen types I and III accumulation in the matrix of burnt tissues. Burn wounds were inflicted on pigs, chosen for the evaluation of wound repair because of many similarities between pig and human skin. Isolated collagen types I and III were estimated by the surface plasmon resonance method with a subsequent collagenous quantification using electrophoretic and densitometric analyses. Propolis burn treatment led to enhanced collagens and its components expression, especially during the initial stage of the study. Less expressed changes were observed after silver sulfadiazine (AgSD) application. AgSD and, with a smaller intensity, propolis stimulated accumulation of collagenous degradation products. The assessed propolis therapeutic efficacy, throughout quantitatively and qualitatively analyses of collagen types I and III expression and degradation in wounds matrix, may indicate that apitherapeutic agent can generate favorable biochemical environment supporting reepithelization.

  9. Aquatic Therapy for a Child with Type III Spinal Muscular Atrophy: A Case Report

    ERIC Educational Resources Information Center

    Salem, Yasser; Gropack, Stacy Jaffee

    2010-01-01

    Spinal muscular atrophy (SMA) is a neuromuscular disorder characterized by degeneration of alpha motor neurons. This case report describes an aquatic therapy program and the outcomes for a 3-year-old girl with type III SMA. Motor skills were examined using the 88-item Gross Motor Function Measure (GMFM), the Peabody Developmental Motor Scales…

  10. Clinical evaluation of a type III secretion system real-time PCR assay for diagnosing melioidosis.

    PubMed

    Meumann, Ella M; Novak, Ryan T; Gal, Daniel; Kaestli, Mirjam E; Mayo, Mark; Hanson, Joshua P; Spencer, Emma; Glass, Mindy B; Gee, Jay E; Wilkins, Patricia P; Currie, Bart J

    2006-08-01

    A Burkholderia pseudomallei type III secretion system real-time PCR assay was evaluated on clinical specimens in a region where melioidosis is endemic. The PCR was positive in 30/33 (91%) patients with culture-confirmed melioidosis. All six patients with melioidosis septic shock were blood PCR positive, suggesting potential for rapid diagnosis and commencement of appropriate therapy.

  11. Hypervirulent Clone of Group B Streptococcus Serotype III Sequence Type 283, Hong Kong, 1993–2012

    PubMed Central

    Ang, Irene; Fung, Kitty; Liyanapathirana, Veranja; Luo, Ming Jing; Lai, Raymond

    2016-01-01

    We describe a hypervirulent clone of group B Streptococcus serotype III, subtype 4, sequence type 283, that caused invasive disease with a predilection for meningitis in Hong Kong during 1993–2012. The organism is associated with high mortality and increased summer prevalence and is linked to diseased fish from freshwater fish farms. PMID:27648702

  12. Hypervirulent Clone of Group B Streptococcus Serotype III Sequence Type 283, Hong Kong, 1993-2012.

    PubMed

    Ip, Margaret; Ang, Irene; Fung, Kitty; Liyanapathirana, Veranja; Luo, Ming Jing; Lai, Raymond

    2016-10-01

    We describe a hypervirulent clone of group B Streptococcus serotype III, subtype 4, sequence type 283, that caused invasive disease with a predilection for meningitis in Hong Kong during 1993-2012. The organism is associated with high mortality and increased summer prevalence and is linked to diseased fish from freshwater fish farms. PMID:27648702

  13. Contribution of Bordetella bronchiseptica Type III secretion system to respiratory disease in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: The type III secretion system (TTSS) of gram negative bacteria allows injection of effector proteins directly into the cytosol of eukaryotic cells. Previous studies have demonstrated that the B. bronchiseptica TTSS plays a role in the persistent bacterial colonization of the trachea of m...

  14. Direct transfer of starter substrates from type I fatty acid synthase to type III polyketide synthases in phenolic lipid synthesis

    PubMed Central

    Miyanaga, Akimasa; Funa, Nobutaka; Awakawa, Takayoshi; Horinouchi, Sueharu

    2008-01-01

    Alkylresorcinols and alkylpyrones, which have a polar aromatic ring and a hydrophobic alkyl chain, are phenolic lipids found in plants, fungi, and bacteria. In the Gram-negative bacterium Azotobacter vinelandii, phenolic lipids in the membrane of dormant cysts are essential for encystment. The aromatic moieties of the phenolic lipids in A. vinelandii are synthesized by two type III polyketide synthases (PKSs), ArsB and ArsC, which are encoded by the ars operon. However, details of the synthesis of hydrophobic acyl chains, which might serve as starter substrates for the type III polyketide synthases (PKSs), were unknown. Here, we show that two type I fatty acid synthases (FASs), ArsA and ArsD, which are members of the ars operon, are responsible for the biosynthesis of C22–C26 fatty acids from malonyl-CoA. In vivo and in vitro reconstitution of phenolic lipid synthesis systems with the Ars enzymes suggested that the C22–C26 fatty acids produced by ArsA and ArsD remained attached to the ACP domain of ArsA and were transferred hand-to-hand to the active-site cysteine residues of ArsB and ArsC. The type III PKSs then used the fatty acids as starter substrates and carried out two or three extensions with malonyl-CoA to yield the phenolic lipids. The phenolic lipids in A. vinelandii were thus found to be synthesized solely from malonyl-CoA by the four members of the ars operon. This is the first demonstration that a type I FAS interacts directly with a type III PKS through substrate transfer. PMID:18199837

  15. Direct transfer of starter substrates from type I fatty acid synthase to type III polyketide synthases in phenolic lipid synthesis.

    PubMed

    Miyanaga, Akimasa; Funa, Nobutaka; Awakawa, Takayoshi; Horinouchi, Sueharu

    2008-01-22

    Alkylresorcinols and alkylpyrones, which have a polar aromatic ring and a hydrophobic alkyl chain, are phenolic lipids found in plants, fungi, and bacteria. In the Gram-negative bacterium Azotobacter vinelandii, phenolic lipids in the membrane of dormant cysts are essential for encystment. The aromatic moieties of the phenolic lipids in A. vinelandii are synthesized by two type III polyketide synthases (PKSs), ArsB and ArsC, which are encoded by the ars operon. However, details of the synthesis of hydrophobic acyl chains, which might serve as starter substrates for the type III polyketide synthases (PKSs), were unknown. Here, we show that two type I fatty acid synthases (FASs), ArsA and ArsD, which are members of the ars operon, are responsible for the biosynthesis of C(22)-C(26) fatty acids from malonyl-CoA. In vivo and in vitro reconstitution of phenolic lipid synthesis systems with the Ars enzymes suggested that the C(22)-C(26) fatty acids produced by ArsA and ArsD remained attached to the ACP domain of ArsA and were transferred hand-to-hand to the active-site cysteine residues of ArsB and ArsC. The type III PKSs then used the fatty acids as starter substrates and carried out two or three extensions with malonyl-CoA to yield the phenolic lipids. The phenolic lipids in A. vinelandii were thus found to be synthesized solely from malonyl-CoA by the four members of the ars operon. This is the first demonstration that a type I FAS interacts directly with a type III PKS through substrate transfer.

  16. Facial nerve dysfunction in hereditary motor and sensory neuropathy type I and III.

    PubMed

    Glocker, F X; Rösler, K M; Linden, D; Heinen, F; Hess, C W; Lücking, C H

    1999-09-01

    Facial nerve function was studied in 19 patients with hereditary motor and sensory neuropathy type I (HMSN I) and 2 patients with hereditary motor and sensory neuropathy type III (HMSN III, Déjérine-Sottas), and compared to that in 24 patients with Guillain-Barré syndrome (GBS). The facial nerve was stimulated electrically at the stylomastoid fossa, and magnetically in its proximal intracanalicular segment. Additionally, the face-associated motor cortex was stimulated magnetically. The facial nerve motor neurography was abnormal in 17 of 19 HMSN I patients and in both HMSN III patients, revealing moderate to marked conduction slowing in both the extracranial and intracranial nerve segments, along with variable reductions of compound muscle action potential (CMAP) amplitudes. The facial nerve conduction slowing paralleled that of limb nerves, but was not associated with clinical dysfunction of facial muscles, because none of the HMSN I patients had facial palsy. Conduction slowing was most severe in the HMSN III patients, but only slight facial weakness was present. In GBS, conduction slowing was less marked, but facial weakness exceeded that in HMSN patients in all cases. We conclude that involvement of the facial nerve is common in HMSN I and HMSN III. It affects the intra- and extracranial part of the facial nerve and is mostly subclinical. PMID:10454715

  17. Energetic electrons, type III radio bursts, and impulsive solar flare X-rays

    SciTech Connect

    Kane, S.R.

    1981-08-01

    Observations of impulsive hard X-ray and type III radio bursts made during the maximum of the last solar activity cycle have been analyzed for a statistical study of the relationship between these two solar flare phenomena. Spectral measurements of 10--68 keV X-rays, which covered 7068 hr of observation time and the range 10/sup -8/ to 10/sup -5/ ergs cm/sup -2/ s/sup -1/ of flux of X-rays > or approx. =20 keV, were made with the University of California (Berkeley) experiment aboard the OGO 5 satellite. The radio data consisted of copies of the original spectral records as well as tabulated data. The principle findings are: (1) about 20% of impulsive hard X-ray bursts are correlated with type III radio bursts; conversely, only approx.3% of the reported type III radio bursts are correlated with impulsive X-rays bursts; (2) the location of the associated H..cap alpha.. flare on the solar disk has little or no effect on the X-ray--type III burst correlation; (3) the magnitude of the X-ray--type III burst correlation increases systematically with the increase in the following quantities: intensity and starting frequency of the type III burst, peak energy flux and spectral hardness of the X-ray burst, and the peak nonthermal emission measure and spectral hardness of the ''instantaneous'' electron spectrum > or approx. =20 keV inside the x-ray source; (4) the observations are consistent with the electron populations responsible for both the X-ray and type III emissions being accelerated in a single acceleration process; (5) the observations suggest a flare model where the primary instability responsible for electron acceleration during the impulsive phase occurs in the corona. The exact location of this instability varies from one flare to another as well as during the impulsive phase of a single flare and determines the hardness of the accelerated electron spectrum and the characteristics of associated X-ray, EUV, optical, and radio emissions.

  18. Synthesis and immunological properties of conjugates composed of group B streptococcus type III capsular polysaccharide covalently bound to tetanus toxoid.

    PubMed

    Lagergard, T; Shiloach, J; Robbins, J B; Schneerson, R

    1990-03-01

    A synthetic scheme for covalently binding group B streptococcus type III to tetanus toxoid (TT), using adipic acid dihydrazide as a spacer, is described. Type III alone or as a conjugate with TT was injected subcutaneously into laboratory mice, and the type-specific and TT antibody responses elicited by these immunogens were assayed. Type III-TT elicited significantly higher levels of type-specific antibodies after each immunization than did the type III alone. These levels were related to the dosage of the conjugate, enhanced by Freund adjuvant, and exhibited booster responses. Type III alone elicited only immunoglobulin M (IgM) antibodies in Swiss albino mice and mostly IgM and low levels of IgG antibodies of the IgG3 subclass in BALB/c mice. Type III-TT conjugates, in contrast, elicited mostly IgG antibodies in both strains of mice. IgA type III antibodies were not detected. The first two immunizations with the conjugates elicited type III antibodies in the IgG1 and in the IgG3 subclasses. Low levels of IgG2a type III antibodies were detected after a third injection of type III-TT. Conjugate-induced antibodies facilitated opsonization of group B streptococcus type III organisms and did not react with the structurally related pneumococcus type 14. TT alone or as a component of type III-TT induced mostly antibodies of the IgG class: IgG1 levels were the highest of the four subclasses. No IgA TT antibodies were detected. The conjugation procedure, therefore, enhanced the immunogenicity of and conferred T-cell dependent properties to the type III while preserving the immunogenicity of the TT component. The T-cell dependent properties of the conjugates were responsible for stimulating IgG type III antibodies which could be boosted. Evaluation of type III-TT conjugates in antibody-negative women of child-bearing age is planned. PMID:2407652

  19. Structural characterization of CFA/III and Longus type IVb pili from enterotoxigenic Escherichia coli.

    PubMed

    Kolappan, Subramaniapillai; Roos, Justin; Yuen, Alex S W; Pierce, Owen M; Craig, Lisa

    2012-05-01

    The type IV pili are helical filaments found on many Gram-negative pathogenic bacteria, with multiple diverse roles in pathogenesis, including microcolony formation, adhesion, and twitching motility. Many pathogenic enterotoxigenic Escherichia coli (ETEC) isolates express one of two type IV pili belonging to the type IVb subclass: CFA/III or Longus. Here we show a direct correlation between CFA/III expression and ETEC aggregation, suggesting that these pili, like the Vibrio cholerae toxin-coregulated pili (TCP), mediate microcolony formation. We report a 1.26-Å resolution crystal structure of CofA, the major pilin subunit from CFA/III. CofA is very similar in structure to V. cholerae TcpA but possesses a 10-amino-acid insertion that replaces part of the α2-helix with an irregular loop containing a 3(10)-helix. Homology modeling suggests a very similar structure for the Longus LngA pilin. A model for the CFA/III pilus filament was generated using the TCP electron microscopy reconstruction as a template. The unique 3(10)-helix insert fits perfectly within the gap between CofA globular domains. This insert, together with differences in surface-exposed residues, produces a filament that is smoother and more negatively charged than TCP. To explore the specificity of the type IV pilus assembly apparatus, CofA was expressed heterologously in V. cholerae by replacing the tcpA gene with that of cofA within the tcp operon. Although CofA was synthesized and processed by V. cholerae, no CFA/III filaments were detected, suggesting that the components of the type IVb pilus assembly system are highly specific to their pilin substrates. PMID:22447901

  20. Structural Characterization of CFA/III and Longus Type IVb Pili from Enterotoxigenic Escherichia coli

    PubMed Central

    Kolappan, Subramaniapillai; Roos, Justin; Yuen, Alex S. W.; Pierce, Owen M.

    2012-01-01

    The type IV pili are helical filaments found on many Gram-negative pathogenic bacteria, with multiple diverse roles in pathogenesis, including microcolony formation, adhesion, and twitching motility. Many pathogenic enterotoxigenic Escherichia coli (ETEC) isolates express one of two type IV pili belonging to the type IVb subclass: CFA/III or Longus. Here we show a direct correlation between CFA/III expression and ETEC aggregation, suggesting that these pili, like the Vibrio cholerae toxin-coregulated pili (TCP), mediate microcolony formation. We report a 1.26-Å resolution crystal structure of CofA, the major pilin subunit from CFA/III. CofA is very similar in structure to V. cholerae TcpA but possesses a 10-amino-acid insertion that replaces part of the α2-helix with an irregular loop containing a 310-helix. Homology modeling suggests a very similar structure for the Longus LngA pilin. A model for the CFA/III pilus filament was generated using the TCP electron microscopy reconstruction as a template. The unique 310-helix insert fits perfectly within the gap between CofA globular domains. This insert, together with differences in surface-exposed residues, produces a filament that is smoother and more negatively charged than TCP. To explore the specificity of the type IV pilus assembly apparatus, CofA was expressed heterologously in V. cholerae by replacing the tcpA gene with that of cofA within the tcp operon. Although CofA was synthesized and processed by V. cholerae, no CFA/III filaments were detected, suggesting that the components of the type IVb pilus assembly system are highly specific to their pilin substrates. PMID:22447901

  1. Disturbances in affective touch in hereditary sensory & autonomic neuropathy type III.

    PubMed

    Macefield, Vaughan G; Norcliffe-Kaufmann, Lucy; Löken, Line; Axelrod, Felicia B; Kaufmann, Horacio

    2014-07-01

    Hereditary sensory and autonomic neuropathy type III (HSAN III, Riley-Day syndrome, Familial Dysautomia) is characterised by elevated thermal thresholds and an indifference to pain. Using microelectrode recordings we recently showed that these patients possess no functional stretch-sensitive mechanoreceptors in their muscles (muscle spindles), a feature that may explain their lack of stretch reflexes and ataxic gait, yet patients have apparently normal low-threshold cutaneous mechanoreceptors. The density of C-fibres in the skin is markedly reduced in patients with HSAN III, but it is not known whether the C-tactile afferents, a distinct type of low-threshold C fibre present in hairy skin that is sensitive to gentle stroking and has been implicated in the coding of pleasant touch are specifically affected in HSAN III patients. We addressed the relationship between C-tactile afferent function and pleasant touch perception in 15 patients with HSAN III and 15 age-matched control subjects. A soft make-up brush was used to apply stroking stimuli to the forearm and lateral aspect of the leg at five velocities: 0.3, 1, 3, 10 and 30 cm/s. As demonstrated previously, the control subjects rated the slowest and highest velocities as less pleasant than those applied at 1-10 cm/s, which fits with the optimal velocities for exciting C-tactile afferents. Conversely, for the patients, ratings of pleasantness did not fit the profile for C-tactile afferents. Patients either rated the higher velocities as more pleasant than the slow velocities, with the slowest velocities being rated unpleasant, or rated all velocities equally pleasant. We interpret this to reflect absent or reduced C-tactile afferent density in the skin of patients with HSAN III, who are likely using tactile cues (i.e. myelinated afferents) to rate pleasantness of stroking or are attributing pleasantness to this type of stimulus irrespective of velocity.

  2. Type III interferons are expressed by Coxsackievirus-infected human primary hepatocytes and regulate hepatocyte permissiveness to infection

    PubMed Central

    Lind, K; Svedin, E; Utorova, R; Stone, V M; Flodström-Tullberg, M

    2014-01-01

    Hepatitis is a common and potentially fatal manifestation of severe Coxsackievirus infections, particularly in newborn children. Little is known of the immune-mediated mechanisms regulating permissiveness to liver infection. It is well established that type I interferons (IFNs) play an important role in the host innate immune response to Coxsackievirus infections. Recent studies have highlighted a role for another IFN family, the type III IFNs (also called IFN-λ), in anti-viral defence. Whether type III IFNs are produced by hepatocytes during a Coxsackievirus infection remains unknown. Moreover, whether or not type III IFNs protects hepatocytes from a Coxsackievirus infection has not been addressed. In this study, we show that primary human hepatocytes respond to a Coxsackievirus B3 (CVB3) infection by up-regulating the expression of type III IFNs. We also demonstrate that type III IFNs induce an anti-viral state in hepatocytes characterized by the up-regulated expression of IFN-stimulated genes, including IFN-stimulated gene (ISG15), 2′-5′-oligoadenylate synthetase 2 (OAS2), protein kinase regulated by dsRNA (PKR) and myxovirus resistance protein 1 (Mx1). Furthermore, our study reveals that type III IFNs attenuate CVB3 replication both in hepatocyte cell lines and primary human hepatocytes. Our studies suggest that human hepatocytes express type III IFNs in response to a Coxsackievirus infection and highlight a novel role for type III IFNs in regulating hepatocyte permissiveness to this clinically relevant type of virus. PMID:24773058

  3. Osteogenesis imperfecta type III in South Africa: Psychosocial challenges.

    PubMed

    Stephen, L X G; Roberts, T; Van Hayden, E; Chetty, M

    2016-01-01

    Individuals with osteogenesis imperfecta type III (OI III) are severely physically disabled due to frequent fracturing. Their disability poses numerous barriers that challenge their social development. Despite these limitations, several affected persons are able to rise above these problems and achieve success in their personal and professional life. This outcome is directly relevant to their psychosocial development.The achievements of five individuals with OI III living in Cape Town are highlighted in this article, as well as the challenges that they have experienced and continue to experience in their daily lives. The authors intend to promulgate understanding of the psychosocial circumstances of affected persons, thereby facilitating the deployment of appropriate efforts and resources to address these challenges. PMID:27245537

  4. Features of the duration frequency dependence for type III solar radio bursts

    NASA Astrophysics Data System (ADS)

    Tsybko, Y. G.

    1989-11-01

    Averaged data on type III solar radio bursts at fixed frequencies in the 12.5-25 MHz range and beyond are examined, showing that there are two branches of the burst duration dependence on frequency. This splitting is used to distinguish between bursts occurring at the fundamental and the second harmonics of the plasma frequency. Type IIIb radiation is characterized by a diagram of the mean duration vs frequency of the stria bursts at the fundamental harmonic. Type III bursts at meter and decameter wavelengths are compared, showing a change in the behavior of the duration frequency dependence. It is suggested that this change may be associated with the initial acceleration and the subsequent expansion of the source along its path in the lower and intermediate corona.

  5. RNA Targeting by the Type III-A CRISPR-Cas Csm Complex of Thermus thermophilus

    PubMed Central

    Staals, Raymond H. J.; Zhu, Yifan; Taylor, David W.; Kornfeld, Jack E.; Sharma, Kundan; Barendregt, Arjan; Koehorst, Jasper J.; Vlot, Marnix; Neupane, Nirajan; Varossieau, Koen; Sakamoto, Keiko; Suzuki, Takehiro; Dohmae, Naoshi; Yokoyama, Shigeyuki; Schaap, Peter J.; Urlaub, Henning; Heck, Albert J. R.; Nogales, Eva; Doudna, Jennifer A.; Shinkai, Akeo; van der Oost, John

    2015-01-01

    SUMMARY CRISPR-Cas is a prokaryotic adaptive immune system that provides sequence-specific defense against foreign nucleic acids. Here we report the structure and function of the effector complex of the Type III-A CRISPR-Cas system of Thermus thermophilus: the Csm complex (TtCsm). TtCsm is composed of five different protein subunits (Csm1–Csm5) with an uneven stoichiometry and a single crRNA of variable size (35–53 nt). The TtCsm crRNA content is similar to the Type III-B Cmr complex, indicating that crRNAs are shared among different subtypes. A negative stain EM structure of the TtCsm complex exhibits the characteristic architecture of Type I and Type III CRISPR-associated ribonucleoprotein complexes. crRNA-protein crosslinking studies show extensive contacts between the Csm3 backbone and the bound crRNA. We show that, like TtCmr, TtCsm cleaves complementary target RNAs at multiple sites. Unlike Type I complexes, interference by TtCsm does not proceed via initial base pairing by a seed sequence. PMID:25457165

  6. Observations of the Flux Density of Some Interplanetary Type II and Type III Radio Bursts and Initial Comparisons With Theory

    NASA Astrophysics Data System (ADS)

    Cairns, I. H.; Mohamed, A. A. A.; Hillan, D.; Robinson, P. A.

    2015-12-01

    The measured intensity of a radio signal depends on the effective antenna length, which may vary with (at least) the plasma properties and radiation frequency. Here the effective antenna lengths are estimated as a function of frequency for the RAD1 and RAD2 instruments on the WIND spacecraft when in SUM mode. This is done by calibrating against the known galactic background radiation spectrum after removal of receiver noise and thermal plasma noise where possible. Flux density spectra and lower limits to the maximum brightness temperature are determined for three type II and three type III radio bursts based on two calibration methods, one of which uses the effective antenna lengths as a function of frequency. The second calibration method uses Wind data for the relative flux in dB to equate the minimum flux observed with the galactic background and receiver noise. The results emphasize that the second method is more successful in obtaining calibrated type II and III fluxes. Calibrated flux densities obtained show that The type IIs have similar maximum flux densities to the type III events in this sample, but the type IIs are much more variable in frequency and time. Theoretical predictions are obtained for shocks moving with a suitable range of initial speeds and accelerations. Dynamic spectra are then predicted for the three selected type II events using the theory of Knock et al. [2001] and a simple, unstructured, solar wind model. Because of the continuous emission of 24-26 August 1998 that is present in a wide range from 100 MHz to 21 kHz, albeit with strongly varying intensity, a comparison between its observed and predicted dynamic spectra is presented. The agreement between theory and data is discussed and the implications described for future modeling.

  7. Induction of tumor necrosis factor alpha by the group- and type-specific polysaccharides from type III group B streptococci.

    PubMed Central

    Mancuso, G; Tomasello, F; von Hunolstein, C; Orefici, G; Teti, G

    1994-01-01

    Previous studies suggested that circulating tumor necrosis factor alpha (TNF-alpha) may have a pathophysiologic role in experimental neonatal sepsis induced by group B streptococci (GBS). This study was undertaken to investigate the ability of the type III and group-specific polysaccharides of GBS to induce TNF-alpha production and TNF-alpha-dependent lethality in neonatal rats. The cytokine was detected in plasma samples by the L929 cytotoxicity assay. Intracardiac injections of either polysaccharide induced dose-dependent, transient elevations in plasma TNF-alpha levels that returned to baseline values after 5 h. The group-specific antigen induced significantly higher mean peak TNF-alpha levels than the type III antigen (125 +/- 47 versus 44 +/- 15 U/ml with 70 mg/kg of body weight). Glycogen (70 mg/kg), used as a negative control, did not induce TNF-alpha. The lipopolysaccharide-neutralizing agent polymyxin B did not decrease TNF-alpha levels induced by either polysaccharide, ruling out contamination with endotoxin as a possible cause of TNF-alpha induction. Fifty percent lethal doses of the type III and group-specific antigens given as intracardiac injections were 105 and 16 mg/kg, respectively. Salmonella endotoxin, used as a positive control, had a 50% lethal dose of 0.1 mg/kg. The lethal activities of GBS polysaccharides, as well as endotoxin, were completely prevented by pretreatment of neonatal rats with the respective specific antibodies or anti-murine TNF-alpha serum. To assess the relative importance of the type-specific substance in TNF-alpha induction by whole bacteria, two unrelated GBS transposon mutants devoid of only the type-specific capsular polysaccharide (COH1-13 and COH31-15) were employed. Each of the heat-killed unencapsulated mutants was able to produce plasma TNF-alpha level elevations or TNF-alpha-dependent lethality but was significantly less efficient in these activities than the corresponding encapsulated wild-type strain. These data

  8. Bianchi type-I, type-III and Kantowski-Sachs solutions in f( T) gravity

    NASA Astrophysics Data System (ADS)

    Rodrigues, M. E.; Kpadonou, A. V.; Rahaman, F.; Oliveira, P. J.; Houndjo, M. J. S.

    2015-06-01

    In the context of modified tele-parallel theory of gravity, we undertake cosmological anisotropic models and search for their solutions. Within a suitable choice of non-diagonal tetrads, the decoupled equations of motion are obtained for Bianchi-I, Bianchi-III and Kantowski-Sachs models, from which we obtain the correspondent solutions. By the way, energy density and pressures are also obtained, showing, as an important result, that our universe may live a quintessence like universe even while anisotropic models are considered.

  9. The Class of Type III-L Solar Radio Bursts and Their Associations with Solar Energetic Proton Events

    NASA Astrophysics Data System (ADS)

    Duffin, Robert Thomas

    2011-05-01

    The source protons of Solar Energetic particle Proton events (defined as "SEP" events for this research) not associated with the Coronal Mass Ejection (CME) shock front are thought to come from either the flare site or the reconnection region beneath the CME. The Type III-L, a new class of solar radio burst has been defined by Cane et al. (2002) and MacDowall et al. (2003) as a sub-set of the Type III burst, beginning after the onset of the soft X-ray (SXR) flare, is long lasting and extends down to at least 1 MHz. The emission source region of Type III-Ls is believed to be at the reconnection region beneath the CME or on the flanks of the CME. Past association studies between SEP events and Type III-Ls began with a biased SEP-selected sample set to see if there can be found support for the emission source region of Type III-Ls and SEPs to come from the same accelerator site at the reconnection region beneath the CME. Unlike previous studies using an SEP-selected sample, I find that when using a radio-selected sample for well-connected SEP events with a solar source in the western hemisphere, the majority of the Type III-L events are associated with SEP events, but not all, and that Type III-L events associated with M- and X- class SXR flares, do not appear to be better predictors of SEP events than do Type II bursts which are associated with the CME shock. Also, I find that the occurrence of Type II events in the radio spectra of SEPs is just as common as the occurrence of Type III-Ls. This indicates that Type III-Ls should not be used as a predictor for SEP events, that the emission source region of Type III-Ls might not be at the reconnection region beneath the CME and reduces the strength of the support found by previous SEP-Type III-L association studies, that the source protons for SEP events necessarily come from the reconnection region beneath the CME. I found that Type III-L events have no strong longitude preference, but SEP events do have a 60

  10. Dentin phosphoprotein compound mutation in dentin sialophosphoprotein causes dentinogenesis imperfecta type III.

    PubMed

    Dong, Juan; Gu, TingTing; Jeffords, Leticia; MacDougall, Mary

    2005-01-30

    A rare compound mutation involving a 36 bp deletion and 18 bp insertion within exon 5 of the dentin sialophosphoprotein (DSPP) gene has been identified in a family with dentinogenesis imperfecta type III (DGI-III). The DSPP gene encodes two major tooth matrix proteins dentin sialoprotein (DSP) and dentin phosphoprotein (DPP). DSPP mutations associated with DGI-III results in an in frame truncation of the serine aspartic acid triplet repeat found in DPP near the highly conserved carboxyl terminal region shortening the protein by six amino acids. Clinically this family presents with discolored amber opalescent teeth and severe attrition of the tooth structure. This study is the first report of a mutation within DPP associated with a genetic dentin disease. Our study indicates that DGI-III is allelic with some forms of DGI-II with and without progressive hearing loss and dentin dysplasia type II that have been shown to be caused by mutations within the DSP coding or signal peptide regions.

  11. Bacterially expressed and refolded envelope protein (domain III) of dengue virus type-4 binds heparan sulfate.

    PubMed

    Pattnaik, Priyabrata; Babu, J Pradeep; Verma, Shailendra Kumar; Tak, Vijay; Rao, P V Lakshmana

    2007-02-01

    An arboviral infection like dengue fever/dengue hemorrhagic fever (DHF) with high morbidity and mortality rate are extensively prevalent in several parts of the world. Global efforts have been directed towards development of vaccine for prevention of dengue. However, lack of thorough understanding about biology and pathogenesis of dengue virus restricts us from development of an effective vaccine. Here we report molecular interaction of domain III of envelope protein of dengue virus type-4 with heparan sulfate. A codon optimized synthetic gene encoding domain III of dengue virus type-4 envelope protein was expressed in Escherichia coli and purified under denaturing conditions, refolded and purified to homogeneity. Refolded Den4-DIII was characterized using biochemical and biophysical methods and shown to be pure and homogeneous. The purified protein was recognized in Western analyses by monoclonal antibody specific for the 6x His tag as well as the H241 monoclonal antibody. The in vitro refolded recombinant protein preparation was biologically functional and found to bind cell free heparan sulfate. This is the first report providing molecular evidence on binding of dengue-4 envelope protein to heparan sulfate. We developed a homology model of dengue-4 envelope protein (domain III) and mapped the possible amino acid residues critical for binding to heparan sulfate. Domain III envelope protein of dengue virus is a lead vaccine candidate. Our findings further the understanding on biology of dengue virus and will help in development of bioassay for the proposed vaccine candidate.

  12. Visualization of the type III secretion sorting platform of Shigella flexneri.

    PubMed

    Hu, Bo; Morado, Dustin R; Margolin, William; Rohde, John R; Arizmendi, Olivia; Picking, Wendy L; Picking, William D; Liu, Jun

    2015-01-27

    Bacterial type III secretion machines are widely used to inject virulence proteins into eukaryotic host cells. These secretion machines are evolutionarily related to bacterial flagella and consist of a large cytoplasmic complex, a transmembrane basal body, and an extracellular needle. The cytoplasmic complex forms a sorting platform essential for effector selection and needle assembly, but it remains largely uncharacterized. Here we use high-throughput cryoelectron tomography (cryo-ET) to visualize intact machines in a virulent Shigella flexneri strain genetically modified to produce minicells capable of interaction with host cells. A high-resolution in situ structure of the intact machine determined by subtomogram averaging reveals the cytoplasmic sorting platform, which consists of a central hub and six spokes, with a pod-like structure at the terminus of each spoke. Molecular modeling of wild-type and mutant machines allowed us to propose a model of the sorting platform in which the hub consists mainly of a hexamer of the Spa47 ATPase, whereas the MxiN protein comprises the spokes and the Spa33 protein forms the pods. Multiple contacts among those components are essential to align the Spa47 ATPase with the central channel of the MxiA protein export gate to form a unique nanomachine. The molecular architecture of the Shigella type III secretion machine and its sorting platform provide the structural foundation for further dissecting the mechanisms underlying type III secretion and pathogenesis and also highlight the major structural distinctions from bacterial flagella. PMID:25583506

  13. Visualization of the type III secretion sorting platform of Shigella flexneri.

    PubMed

    Hu, Bo; Morado, Dustin R; Margolin, William; Rohde, John R; Arizmendi, Olivia; Picking, Wendy L; Picking, William D; Liu, Jun

    2015-01-27

    Bacterial type III secretion machines are widely used to inject virulence proteins into eukaryotic host cells. These secretion machines are evolutionarily related to bacterial flagella and consist of a large cytoplasmic complex, a transmembrane basal body, and an extracellular needle. The cytoplasmic complex forms a sorting platform essential for effector selection and needle assembly, but it remains largely uncharacterized. Here we use high-throughput cryoelectron tomography (cryo-ET) to visualize intact machines in a virulent Shigella flexneri strain genetically modified to produce minicells capable of interaction with host cells. A high-resolution in situ structure of the intact machine determined by subtomogram averaging reveals the cytoplasmic sorting platform, which consists of a central hub and six spokes, with a pod-like structure at the terminus of each spoke. Molecular modeling of wild-type and mutant machines allowed us to propose a model of the sorting platform in which the hub consists mainly of a hexamer of the Spa47 ATPase, whereas the MxiN protein comprises the spokes and the Spa33 protein forms the pods. Multiple contacts among those components are essential to align the Spa47 ATPase with the central channel of the MxiA protein export gate to form a unique nanomachine. The molecular architecture of the Shigella type III secretion machine and its sorting platform provide the structural foundation for further dissecting the mechanisms underlying type III secretion and pathogenesis and also highlight the major structural distinctions from bacterial flagella.

  14. In Situ Detection of Strong Langmuir Turbulence Processes in Solar Type III Radio Bursts

    NASA Technical Reports Server (NTRS)

    Golla, Thejappa; Macdowall, Robert J.; Bergamo, M.

    2012-01-01

    The high time resolution observations obtained by the WAVES experiment of the STEREO spacecraft in solar type III radio bursts show that Langmuir waves often occur as intense localized wave packets. These wave packets are characterized by short durations of only a few ms and peak intensities, which well exceed the supersonic modulational instability (MI) thresholds. These timescales and peak intensities satisfy the criterion of the solitons collapsed to spatial scales of a few hundred Debye lengths. The spectra of these wave packets consist of primary spectral peaks corresponding to beam-resonant Langmuir waves, two or more sidebands corresponding to down-shifted and up-shifted daughter Langmuir waves, and low frequency enhancements below a few hundred Hz corresponding to daughter ion sound waves. The frequencies and wave numbers of these spectral components satisfy the resonance conditions of the modulational instability (MI). Moreover, the tricoherences, computed using trispectral analysis techniques show that these spectral components are coupled to each other with a high degree of coherency as expected of the MI type of four wave interactions. The high intensities, short scale lengths, sideband spectral structures and low frequency spectral enhancements and, high levels of tricoherences amongst the spectral components of these wave packets provide unambiguous evidence for the supersonic MI and related strong turbulence processes in type III radio bursts. The implication of these observations include: (1) the MI and related strong turbulence processes often occur in type III source regions, (2) the strong turbulence processes probably play very important roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation at the fundamental and second harmonic of the electron plasma frequency, fpe, and (3) the Langmuir collapse probably follows the route of MI in type III radio bursts.

  15. Effects of Spatial Variations in Coronal Temperatures on Type III Bursts. I. Variations in Electron Temperature

    NASA Astrophysics Data System (ADS)

    Li, B.; Cairns, Iver H.; Robinson, P. A.

    2011-03-01

    The electron temperature Te and ion temperature Ti in the corona vary with time and location, due to transient and persistent activity on the Sun. A method is developed for incorporating spatial variations of coronal temperatures into our previous simulation model for coronal type III bursts. The effects on type III bursts are simulated here for monotonic Te variations and/or for spatially localized disturbances in Te . Localized Te disturbances are found to have stronger effects than monotonic variations. In the presence of localized Te disturbances, the dynamic spectra of fp and 2fp emission are modulated at frequencies corresponding to the disturbances, showing intense fine structures that are narrow band and slowly drifting. The fp emission may be observable although still significantly weaker and more patchy than the 2fp emission. Distinct signatures of Te disturbances are found in the dependence on frequency of the 2fp spectral characteristics, e.g., the maximum flux. In the presence of monotonically varying Te , the frequency drift rate for 2fp emission agrees quantitatively with an extended version of the standard prediction, depending on the plasma density profile and a characteristic, non-constant beam speed, which varies with position via dependence on Te , and agrees quantitatively with the simulated beam dynamics. The results thus indicate that nonthermal type III bursts offer a new tool to probe both spatially localized Te structures and monotonic Te variations in the corona. The presence of localized Te disturbances may be responsible for some fine structures in type IIIs, e.g., the flux modulations in type IIIb bursts.

  16. Type III Guyon Syndrome in 'B Boy' Break-Dancer: A Case Report.

    PubMed

    Hu, Soo-Young; Choi, Jin-Gyu; Son, Byung-Chul

    2015-10-01

    Although the musculoskeletal injuries associated with break-dancing which is gaining more popularity among adolescent and young people has been reported, the report regarding a peripheral nerve injury associated with breakdance is scarce. We report a rare case of a young amateur break-dancer, 'b-boy' who suffered from a painful paresthesia in his left hand, later diagnosed as type III Guyon's canal syndrome. A 23-year-old, right handed college man presented with a tenderness over the left hypothenar eminence and painful paresthesia over the ring and little fingers of 3 months duration. He trained himself as an amateur 'b boy' break-dancer for the last 10 months. Conservative management under the diagnosis of wrist sprain before presentation did not improve his hand pain. An magnetic resonance imaging and electrodiagnostic study revealed that painful paresthesia was caused by type III Guyon's canal syndrome, and 4 weeks of corticosteroid treatment was given with resolution of pain and paresthesia.

  17. Type III radio bursts in the interplanetary medium - The role of propagation

    NASA Technical Reports Server (NTRS)

    Steinberg, J. L.; Hoang, S.; Lecacheux, A.; Aubier, M. G.; Dulk, G. A.

    1984-01-01

    Interplanetary type III radio burst observations are analyzed in order to ascertain the role played by propagation effects between the true source and the observer. Large source altitudes are noted, together with an increasing angular size of sources with increasing angular distance from the sun's center. These and other observations furnish strong evidence for the theory that propagation effects, group delays, ducting and/or scattering significantly affect the observed heights, sizes, and brightness temperatures of interplanetary type III bursts. This would be true irrespective of whether the bursts are due to plasma radiation at the fundamental or at the harmonic, and the effects would extend to the arrival times of the radiation to a greater or lesser extent, depending on the path from the source to the observer.

  18. Type III secretion genes identify a putative virulence locus of Chlamydia.

    PubMed

    Hsia, R C; Pannekoek, Y; Ingerowski, E; Bavoil, P M

    1997-07-01

    Four genes of Chlamydia psittaci strain guinea pig inclusion conjunctivitis (GPIC), whose predicted products are highly homologous to structural and regulatory components of a contact-dependent or type III secretion apparatus, were isolated. Related to genes present in several animal and plant bacterial pathogens, these genes may represent a section of a previously undetected chromosomal virulence locus analogous to several recently described virulence-associated type III secretion loci. The existence of contact-dependent secretion in Chlamydia strongly suggests that these bacteria use pathogenic mechanisms that are similar to those of other intracellular bacterial pathogens. Unlike other intracellular bacteria, however, chlamydiae are metabolically inactive extracellularly and only become capable of global protein synthesis several hours after infection. This implies that chlamydial contact-dependent secretion is only active from within, uniquely after the bacteria have been internalized by eukaryotic cells. The possible role(s) of this pathway in chlamydial pathogenesis are discussed.

  19. Mutations in the 4-hydroxyphenylpyruvate dioxygenase gene (HPD) in patients with tyrosinemia type III.

    PubMed

    Rüetschi, U; Cerone, R; Pérez-Cerda, C; Schiaffino, M C; Standing, S; Ugarte, M; Holme, E

    2000-06-01

    Tyrosinemia type III (OMIM 276710) is an autosomal recessive disorder caused by the deficiency of 4-hydroxyphenylpyruvate dioxygenase (HPD), the second enzyme in the tyrosine catabolic pathway. The enzyme deficiency results in an accumulation and increased excretion of tyrosine and phenolic metabolites. Only a few cases with the disorder have been described, and the clinical spectrum of the disorder is unknown. Reported patients have presented with mental retardation or neurological symptoms or have been picked up by neonatal screening. We have identified four presumed pathogenic mutations (two missense and two nonsense mutations) in the HPD gene in three unrelated families encompassing four homozygous individuals and one compound heterozygous individual with tyrosinemia type III. Furthermore, a number of polymorphic mutations have been identified in the HPD gene. No correlation of the severity of the mutation and enzyme deficiency and mental function has been found; neither do the recorded tyrosine levels correlate with the clinical phenotype.

  20. Structure of a fibronectin type III-like module from Clostridium thermocellum

    PubMed Central

    Alahuhta, Markus; Xu, Qi; Brunecky, Roman; Adney, William S.; Ding, Shi-You; Himmel, Michael E.; Lunin, Vladimir V.

    2010-01-01

    The 1.6 Å resolution structure of a fibronectin type III-like module from Clostridium thermocellum (PDB code 3mpc) with two molecules in the asymmetric unit is reported. The crystals used for data collection belonged to space group P212121, with unit-cell parameters a = 35.43, b = 45.73, c = 107.72 Å, and the structure was refined to an R factor of 0.166. Structural comparisons found over 800 similar structures in the Protein Data Bank. The broad range of different proteins or protein domains with high structural similarity makes it especially demanding to classify these proteins. Previous studies of fibronectin type III-like modules have indicated that they might function as ligand-binding modules, as a compact form of peptide linkers or spacers between other domains, as cellulose-disrupting modules or as proteins that help large enzyme complexes remain soluble. PMID:20693658

  1. Evidence for nonlinear wave-wave interactions in solar type III radio bursts

    NASA Technical Reports Server (NTRS)

    Lin, R. P.; Levedahl, W. K.; Lotko, W.; Gurnett, D. A.; Scarf, F. L.

    1986-01-01

    Evidence is presented that nonlinear wave-wave interactions occur in type III solar radio bursts. Intense, spiky Langmuir waves are observed to be driven by electron beams associated with type III solar radio bursts in the interplanetary medium. Bursts of 30-300 Hz (in the spacecraft frame) waves are often observed coincident in time with the most intense spikes of the Langmuir waves. These low-frequency waves appear to be long-wavelength ion acoustic waves, with wavenumber approximately equal to the beam resonant Langmuir wavenumber. Three possible interpretations of these observations are considered: modulational instability, parametric decay of the parent Langmuir waves to daughter ion acoustic and Langmuir waves, and decay to daughter electromagnetic waves and ion acoustic waves.

  2. On Speeds of Exciter Beams of Interplanetary Type III Radio Bursts

    NASA Astrophysics Data System (ADS)

    Krupar, V.; Kontar, E.; Soucek, J.; Santolik, O.; Maksimovic, M.; Kruparova, O.

    2014-12-01

    Type III radio bursts are intense radio emissions triggered by beams of energetic electrons often associated with solar flares. These exciter beams propagate outward the Sun along an open magnetic field line in the corona and the interplanetary medium at large distances beyond 1 AU, where energetic electrons can be detected in situ by spacecraft. We performed a statistical survey of 20 simple and isolated interplanetary Type III radio bursts observed by STEREO/Waves between January 2013 and June 2014. We investigated time - frequency profiles to derive speeds of exciter electron beams. We present evidence that these beams decelerate in the solar wind. Obtained beam speeds range from 0.05c up to 0.55c depending on initial assumptions. It corresponds to electron energies between tens of eV and hundreds of keV.

  3. Harmonic structure of decametric Type III emission and radio wave group delay in the solar corona

    NASA Astrophysics Data System (ADS)

    Abranin, Eh. P.; Bazelyan, L. L.; Tsybko, Ya. G.; Abranin, Eh. P.; Bazelyan, L. L.; Tsybko, Ya. G.

    1993-08-01

    Solar observations with the UTR-2 decameter-wave radio telescope antenna, performed continuously at fixed frequencies from 25 to 10 MHz during Type III, IIIb-III noise storms from 1979 to 1984, have yielded new data on the frequency drift rates Delta(f)/Delta(tf) of numerous type IIIF, IIIFb, and IIIH(b) decameter radio bursts in several narrow bands Delta(f). The data confirm that the burst drift rates are virtually independent of the phase of the 11-yr solar activity cycle. Measurements of the drift time intervals for bursts drifting over narow bands (25-20 and 12.5-10 MHZ) separated by an octave prove the reliability of the radio burst harmonic classification in which there is a clear differentiation between the emission components coinciding with the fundamental and the second harmonic of the local plasma frequency.

  4. Type-III Bifurcation to Chaos in Self-Oscillating States of Squid Giant Axons

    NASA Astrophysics Data System (ADS)

    Shimokawa, Kazuro; Hanyu, Yoshiro; Matsumoto, Gen

    1998-07-01

    This paper describes detailed bifurcation characteristics of firing (time sequence of action potentials) observed in squid giant axons as a function of temperature.The firing is spontaneously induced when the axon is immersed in Ca-reduced ASW (Artificial seawater) without any electrical stimulation.The firing observed above a critical temperature (high-temperature phase firing) is periodic, while the one below the critical temperature (low-temperature) is aperiodic.Our present analysis on the firing shows that aperiodic firing is chaotic, and bifurcation from periodic oscillation to chaos occurs through the type-III intermittency.The type-III bifurcation to chaos should take place through some temperature-dependent properties of the axonal membrane in itself.One of the most probable candidates underlying chaos and bifurcation mechanisms in this experiment could be temperature-dependednt spatial interaction along the longitudinal direction of the squid giant axon.

  5. Structural Dissection of the Extracellular Moieties of the Type III Secretion Apparatus

    PubMed Central

    Wang, Yu; Zhang, Lingling; Picking, Wendy L.; Picking, William D.; De Guzman, Roberto N.

    2013-01-01

    Summary Many Gram-negative bacterial pathogens use type III secretion systems (TTSSs) for subverting the normal cellular functions of their target eukaryotic cells. The type III secretion apparatus (TTSA) functions like a syringe to inject proteins through an external needle and into a target cell’s membrane and cytosol. The TTSA basal body spans the bacterial inner and outer membranes, and the external needle is topped with a tip complex that controls the secretion and delivery of translocator and effector proteins. Recent structures of TTSA proteins have greatly advanced our understanding of shared themes in apparatus assembly and function. In this review, the structure-function of TTSA needle and tip complex proteins are described and common themes discussed. PMID:19396380

  6. Clumpy Langmuir waves in type III radio sources - Comparison of stochastic-growth theory with observations

    NASA Technical Reports Server (NTRS)

    Robinson, P. A.; Cairns, I. H.; Gurnett, D. A.

    1993-01-01

    Detailed comparisons are made between the Langmuir-wave properties predicted by the recently developed stochastic-growth theory of type III sources and those observed by the plasma wave experiment on ISEE 3, after correcting for the main instrumental and selection effects. Analysis of the observed field-strength distribution confirms the theoretically predicted form and implies that wave growth fluctuates both spatially and temporally in sign and magnitude, leading to an extremely clumpy distribution of fields. A cutoff in the field-strength distribution is seen at a few mV/m, corresponding to saturation via nonlinear effects. Analysis of the size distribution of Langmuir clumps yields results in accord with those obtained in earlier work and with the size distribution of ambient density fluctuations in the solar wind. This confirms that the inhomogeneities in the Langmuir growth rate are determined by the density fluctuations and that these fluctuations persist during type III events.

  7. Iron starvation regulates the type III secretion system in Bordetella bronchiseptica.

    PubMed

    Kurushima, Jun; Kuwae, Asaomi; Abe, Akio

    2012-06-01

    The type III secretion system (T3SS) plays a key role in the exertion of full virulence by Bordetella bronchiseptica. However, little is known about the environmental stimuli that induce expression of T3SS genes. Here, it is reported that iron starvation is a signal for T3SS gene expression in B. bronchiseptica. It was found that, when B. bronchiseptica is cultured under iron-depleted conditions, secretion of type III secreted proteins is greater than that in bacteria grown under iron-replete conditions. Furthermore, it was confirmed that induction of T3SS-dependent host cell cytotoxicity and hemolytic activity is greatly enhanced by infection with iron-depleted Bordetella. In contrast, production of filamentous hemagglutinin is reduced in iron-depleted Bordetella. Thus, B. bronchiseptica controls the expression of virulence genes in response to iron starvation.

  8. A COL2A1 mutation in achondrogenesis type II results in the replacement of type II collagen by type I and III collagens in cartilage.

    PubMed

    Chan, D; Cole, W G; Chow, C W; Mundlos, S; Bateman, J F

    1995-01-27

    An autosomal dominant mutation in the COL2A1 gene was identified in a fetus with achondrogenesis type II. A transition of G2853 to A in exon 41 produced a substitution of Gly769 by Ser within the triple helical domain of the alpha 1(II) chain of type II collagen, interrupting the mandatory Gly-X-Y triplet sequence required for the normal formation of stable triple helical type II collagen molecules, resulting in the complete absence of type II collagen in the cartilage, which had a gelatinous composition. Type I and III collagens were the major species found in cartilage tissue and synthesized by cultured chondrocytes along with cartilage type XI collagen. However, cultured chondrocytes produced a trace amount of type II collagen, which was retained within the cells and not secreted. In situ hybridization of cartilage sections showed that the chondrocytes produced both type II and type I collagen mRNA. As a result, it is likely that the chondrocytes produced type II collagen molecules, which were then degraded. The close proximity of the Gly769 substitution by Ser to the mammalian collagenase cleavage site at Gly775-Leu776 may have produced an unstable domain that was highly susceptible to proteolysis. The type I and III collagens that replaced type II collagen were unable to maintain the normal structure of the hyaline cartilage but did support chondrocyte maturation, evidenced by the expression of type X collagen in the hypertrophic zone of the growth plate cartilage. PMID:7829510

  9. Pyopneumothorax with Stocker type III congenital cystic adenomatoid malformation in a 5-month-old infant

    PubMed Central

    Chilkar, Sujeet M; Leelakumar, Venkat; Ranjani, Chakravarthy P; Musthyala, Bharati; Narayana, Kotte VS

    2016-01-01

    Congenital cystic adenomatoid malformation (CCAM) is a rare, developmental, hamartomatous abnormality of the lung characterized by a cessation of normal bronchiolar maturation, resulting in cystic overgrowth of the terminal bronchioles. We report one such case of CCAM in a 5-month-old female infant who was in perfect health until she suffered from spontaneous pyopneumothorax with type III CCAM of the lung and recovered after lobectomy. PMID:27051113

  10. Increased nitric oxide release by neutrophils of a patient with tyrosinemia type III.

    PubMed

    D'Eufemia, Patrizia; Finocchiaro, Roberto; Celli, Mauro; Raccio, Ivana; Properzi, Enrico; Zicari, Alessandra

    2009-06-01

    Tyrosinemia type III (OMIM 276710) is an autosomal recessive disorder caused by the deficiency of 4-hydroxyphenylpyruvate dioxygenase (4-HPD). Few cases have been described with mental retardation or neurological symptoms. Recently it has been demonstrated that 4-HPD participates to nitric oxide (NO) intracellular sequestration in Pseudomonas aeruginosa. 4-HPD is an ubiquitous enzyme with a prominent expression in neutrophils and neurons. In the nervous system NO has been perceived to be a potential neuromodulator although prolonged excessive generation is detrimental. We analyzed NO release by neutrophils of a patient with tyrosinemia type III in order to evaluate a possible influence of 4-HPD deficiency on this process. Our patient, previously described, is a 30-year-old women with persistent tyrosinemia (450-680 micromol/l) and deficient activity of 4-HPD. At 17 months of age she experienced an acute ataxia and drowsiness lasting for 10 days, but further clinical course showed persistent tyrosinemia with normal growth and psychomotor development. Neutrophils isolated from our patient exhibited a NO release greatly higher in respect to the controls (mean+/-SEM 23.2+/-1.8 micromol/10(6) cells vs 3.5+/-0.5 micromol/10(6) cells). Clinical findings of tyrosinemia type III include neurological symptoms and mental retardation but no consistent phenotype has emerged. Therefore the pathogenesis of neurological involvement is yet not well understood. Our results suggest that an excessive neutrophils of NO release could reflect the lack of scavenging action of 4-HPD. Considering the prominent expression of this enzyme in neurons, we hypothesize that excessive NO release could participate in neuronal damage explaining the neurological involvement described in patients with tyrosinemia type III.

  11. Comment on the Brans Dicke Bianchi Type-Iii Vacuum Solution

    NASA Astrophysics Data System (ADS)

    Lorenz-Petzold, Dieter

    1985-02-01

    The author wishes to point out that the Brans-Dicke-Bianchi type-III vacuum solution recently given by Tiwari and Singh (1984) is not new. Moreover, the solution given has no correct Einstein limit, contrary to what is claimed by these authors. The Ellis-MacCallum vacuum solution in the Einstein case can be obtained from the Brans-Dicke solution first given by Lorenz-Petzold (1984).

  12. Stopping frequency of type III solar radio bursts in expanding magnetic flux tubes

    NASA Astrophysics Data System (ADS)

    Reid, Hamish A. S.; Kontar, Eduard P.

    2015-05-01

    Aims: Understanding the properties of type III radio bursts in the solar corona and interplanetary space is one of the best ways to remotely deduce the characteristics of solar accelerated electron beams and the solar wind plasma. One feature of all type III bursts is the lowest frequency they reach (or stopping frequency). This feature reflects the distance from the Sun that an electron beam can drive the observable plasma emission mechanism. The stopping frequency has never been systematically studied before from a theoretical perspective. Methods: Using numerical kinetic simulations, we explore the different parameters that dictate how far an electron beam can travel before it stops inducing a significant level of Langmuir waves, responsible for plasma radio emission. We use the quasilinear approach to model the resonant interaction between electrons and Langmuir waves self-consistently in inhomogeneous plasma, and take into consideration the expansion of the guiding magnetic flux tube and the turbulent density of the interplanetary medium. Results: We find that the rate of radial expansion has a significant effect on the distance an electron beam travels before enhanced levels of Langmuir waves, hence radio waves, cease. Radial expansion of the guiding magnetic flux tube rarefies the electron stream to the extent that the density of non-thermal electrons is too low to drive Langmuir wave production. The initial conditions of the electron beam have a significant effect, where decreasing the beam density or increasing the spectral index of injected electrons would cause higher type III stopping frequencies. We also demonstrate how the intensity of large-scale density fluctuations increases the highest frequency to which Langmuir waves can be driven by the beam and how the magnetic field geometry can be the cause of type III bursts that are only observed at high coronal frequencies.

  13. A comparison of type III solar radio burst theories using satellite radio observations and particle measurements.

    NASA Technical Reports Server (NTRS)

    Evans, L. G.; Fainberg, J.; Stone, R. G.

    1971-01-01

    The required electron density to excite a type III solar burst can be predicted from different theories, using the low frequency radio observations of the RAE-1 satellite. Electron flux measurements by satellite in the vicinity of 1 AU then give an independent means of comparing these predicted exciter electron densities to the measured density. On this basis, one theory predicts the electron density in closest agreement with the measured values.

  14. Overactive bladder after female genital mutilation/cutting (FGM/C) type III.

    PubMed

    Abdulcadir, Jasmine; Dällenbach, Patrick

    2013-10-04

    A 27-year-old Somali woman with type III a-b female genital mutilation/cutting, consulted because of slow micturition, voiding efforts, urgency and urge incontinence (overactive bladder). She also referred primary dysmenorrhoea and superficial dyspareunia making complete sexual intercourses impossible. We treated her by defibulation and biofeedback re-educative therapy. We also offered a multidisciplinary counselling. At 5 months follow-up, urgency and urge incontinence had resolved and she became pregnant.

  15. Observation of local radio emission associated with type III radio bursts and Langmuir waves

    NASA Technical Reports Server (NTRS)

    Reiner, M. J.; Stone, R. G.; Fainberg, J.

    1992-01-01

    The first clear detection of fundamental and harmonic radiation from the type III radio source region is presented. This radiation is characterized by its lack of frequency drift, its short rise and decay times, its relative weakness compared to the remotely observed radiation and its temporal coincidence with observed Langmuir waves. The observations were made with the radio and plasma frequency (URAP) receivers on the Ulysses spacecraft between about 1 and 2 AU from the Sun.

  16. Novel Low Fluence Combination Laser Treatment of Solar Lentigines in Type III Asian Skin

    PubMed Central

    Tian, Brian Wei Cheng Anthony

    2015-01-01

    Objective: To demonstrate a novel low fluence combination laser technique [Erbium-doped yttrium aluminum garnet (Erb:YAG) and neodymium-doped yttrium aluminum garnet (Nd:YAG)] to effectively treat solar lentigines in type III Asian skin in a single session. Design: A prospective study. Setting: A Singapore-based clinic. Participants: Five patients (all females) were enrolled into the study. The ages ranged 35-60 years; all patients had Fitzpatrick skin type III. Measurements: Photographs were taken at baseline and at 1-month follow-up. These were reviewed by two independent physicians who were blinded to the study. Changes in pigment severity were assessed by a 5-point scale (1: Aggravation of pigment, 2: No change, 3: 25-50% improvement, 4: 51-75% improvement, and 5: 76-100% improvement). Results: All patients received a single treatment session. At 1-month follow-up, a reduction in pigment was observed in all patients. Both physicians’ reports were independently agreeable. All patients scored 5, having >90% improvement in pigment severity. No hypopigmentation, postinflammatory hyperpigmentation (PIH), or recurrence was seen. Conclusion: Low fluence combination laser is effective and safe for clearance of solar lentigines in type III Asian skin. PMID:26865789

  17. Neuroinflammation, mitochondrial defects and neurodegeneration in mucopolysaccharidosis III type C mouse model

    PubMed Central

    Martins, Carla; Hůlková, Helena; Dridi, Larbi; Dormoy-Raclet, Virginie; Grigoryeva, Lubov; Choi, Yoo; Langford-Smith, Alexander; Wilkinson, Fiona L.; Ohmi, Kazuhiro; DiCristo, Graziella; Hamel, Edith; Ausseil, Jerôme; Cheillan, David; Moreau, Alain; Svobodová, Eva; Hájková, Zuzana; Tesařová, Markéta; Hansíková, Hana; Bigger, Brian W.; Hrebícek, Martin

    2015-01-01

    Severe progressive neurological paediatric disease mucopolysaccharidosis III type C is caused by mutations in the HGSNAT gene leading to deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase involved in the lysosomal catabolism of heparan sulphate. To understand the pathophysiology of the disease we generated a mouse model of mucopolysaccharidosis III type C by germline inactivation of the Hgsnat gene. At 6–8 months mice showed hyperactivity, and reduced anxiety. Cognitive memory decline was detected at 10 months and at 12–13 months mice showed signs of unbalanced hesitant walk and urinary retention. Lysosomal accumulation of heparan sulphate was observed in hepatocytes, splenic sinus endothelium, cerebral microglia, liver Kupffer cells, fibroblasts and pericytes. Starting from 5 months, brain neurons showed enlarged, structurally abnormal mitochondria, impaired mitochondrial energy metabolism, and storage of densely packed autofluorescent material, gangliosides, lysozyme, phosphorylated tau, and amyloid-β. Taken together, our data demonstrate for the first time that deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase causes lysosomal accumulation of heparan sulphate in microglial cells followed by their activation and cytokine release. They also show mitochondrial dysfunction in the neurons and neuronal loss explaining why mucopolysaccharidosis III type C manifests primarily as a neurodegenerative disease. PMID:25567323

  18. Multiple nucleic acid cleavage modes in divergent type III CRISPR systems

    PubMed Central

    Zhang, Jing; Graham, Shirley; Tello, Agnes; Liu, Huanting; White, Malcolm F.

    2016-01-01

    CRISPR-Cas is an RNA-guided adaptive immune system that protects bacteria and archaea from invading nucleic acids. Type III systems (Cmr, Csm) have been shown to cleave RNA targets in vitro and some are capable of transcription-dependent DNA targeting. The crenarchaeon Sulfolobus solfataricus has two divergent subtypes of the type III system (Sso-IIID and a Cmr7-containing variant of Sso-IIIB). Here, we report that both the Sso-IIID and Sso-IIIB complexes cleave cognate RNA targets with a ruler mechanism and 6 or 12 nt spacing that relates to the organization of the Cas7 backbone. This backbone-mediated cleavage activity thus appears universal for the type III systems. The Sso-IIIB complex is also known to possess a distinct ‘UA’ cleavage mode. The predominant activity observed in vitro depends on the relative molar concentration of protein and target RNA. The Sso-IIID complex can cleave plasmid DNA targets in vitro, generating linear DNA products with an activity that is dependent on both the cyclase and HD nuclease domains of the Cas10 subunit, suggesting a role for both nuclease active sites in the degradation of double-stranded DNA targets. PMID:26801642

  19. Maintenance of an unfolded polypeptide by a cognate chaperone in bacterial type III secretion.

    PubMed

    Stebbins, C E; Galán, J E

    2001-11-01

    Many bacterial pathogens use a type III protein secretion system to deliver virulence effector proteins directly into the host cell cytosol, where they modulate cellular processes. A requirement for the effective translocation of several such effector proteins is the binding of specific cytosolic chaperones, which typically interact with discrete domains in the virulence factors. We report here the crystal structure at 1.9 A resolution of the chaperone-binding domain of the Salmonella effector protein SptP with its cognate chaperone SicP. The structure reveals that this domain is maintained in an extended, unfolded conformation that is wound around three successive chaperone molecules. Short segments from two different SptP molecules are juxtaposed by the chaperones, where they dimerize across a hydrophobic interface. These results imply that the chaperones associated with the type III secretion system maintain their substrates in a secretion-competent state that is capable of engaging the secretion machinery to travel through the type III apparatus in an unfolded or partially folded manner.

  20. Neuroinflammation, mitochondrial defects and neurodegeneration in mucopolysaccharidosis III type C mouse model.

    PubMed

    Martins, Carla; Hůlková, Helena; Dridi, Larbi; Dormoy-Raclet, Virginie; Grigoryeva, Lubov; Choi, Yoo; Langford-Smith, Alexander; Wilkinson, Fiona L; Ohmi, Kazuhiro; DiCristo, Graziella; Hamel, Edith; Ausseil, Jerôme; Cheillan, David; Moreau, Alain; Svobodová, Eva; Hájková, Zuzana; Tesařová, Markéta; Hansíková, Hana; Bigger, Brian W; Hrebícek, Martin; Pshezhetsky, Alexey V

    2015-02-01

    Severe progressive neurological paediatric disease mucopolysaccharidosis III type C is caused by mutations in the HGSNAT gene leading to deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase involved in the lysosomal catabolism of heparan sulphate. To understand the pathophysiology of the disease we generated a mouse model of mucopolysaccharidosis III type C by germline inactivation of the Hgsnat gene. At 6-8 months mice showed hyperactivity, and reduced anxiety. Cognitive memory decline was detected at 10 months and at 12-13 months mice showed signs of unbalanced hesitant walk and urinary retention. Lysosomal accumulation of heparan sulphate was observed in hepatocytes, splenic sinus endothelium, cerebral microglia, liver Kupffer cells, fibroblasts and pericytes. Starting from 5 months, brain neurons showed enlarged, structurally abnormal mitochondria, impaired mitochondrial energy metabolism, and storage of densely packed autofluorescent material, gangliosides, lysozyme, phosphorylated tau, and amyloid-β. Taken together, our data demonstrate for the first time that deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase causes lysosomal accumulation of heparan sulphate in microglial cells followed by their activation and cytokine release. They also show mitochondrial dysfunction in the neurons and neuronal loss explaining why mucopolysaccharidosis III type C manifests primarily as a neurodegenerative disease. PMID:25567323

  1. The platelet receptor for type III collagen (TIIICBP) is present in platelet membrane lipid microdomains (rafts).

    PubMed

    Maurice, Pascal; Waeckel, Ludovic; Pires, Viviane; Sonnet, Pascal; Lemesle, Monique; Arbeille, Brigitte; Vassy, Jany; Rochette, Jacques; Legrand, Chantal; Fauvel-Lafève, Françoise

    2006-04-01

    Platelet interactions with collagen are orchestrated by the presence or the migration of platelet receptor(s) for collagen into lipid rafts, which are specialized lipid microdomains from the platelet plasma membrane enriched in signalling proteins. Electron microscopy shows that in resting platelets, TIIICBP, a receptor specific for type III collagen, is present on the platelet membrane and associated with the open canalicular system, and redistributes to the platelet membrane upon platelet activation. After platelet lysis by 1% Triton X-100 and the separation of lipid rafts on a discontinuous sucrose gradient, TIIICBP is recovered in lipid raft-containing fractions and Triton X-100 insoluble fractions enriched in cytoskeleton proteins. Platelet aggregation, induced by type III collagen, was inhibited after disruption of the lipid rafts by cholesterol depletion, whereas platelet adhesion under static conditions did not require lipid raft integrity. These results indicate that TIIICBP, a platelet receptor involved in platelet interaction with type III collagen, is localized within platelet lipid rafts where it could interact with other platelet receptors for collagen (GP VI and alpha2beta1 integrin) for efficient platelet activation. PMID:16205938

  2. Infection by bacterial pathogens expressing type III secretion decreases luciferase activity: ramifications for reporter gene studies.

    PubMed

    Savkovic, S D; Koutsouris, A; Wu, G; Hecht, G

    2000-09-01

    Pathogenic microbes influence gene regulation in eukaryotic hosts. Reporter gene studies can define the roles of promoter regulatory sequences. The effect of pathogenic bacteria on reporter genes has not been examined. The aim of this study was to identify which reporter genes are reliable in studies concerning host gene regulation by bacterial pathogens expressing type III secretory systems. Human intestinal epithelial cells, T84, Caco-2 and HT-29, were transfected with plasmids containing luciferase (luc), chloramphenicol acetyltransferase (CAT) or beta-galactosidase (beta-gal) as reporter genes driven by the inducible interleukin-8 (IL-8) or constitutively active simian virus 40 (SV40) promoter. Cells were infected with enteropathogenic E. coli or Salmonella typhimurium, and the reporter activity was assessed. Luc activity significantly decreased following infection, regardless of the promoter. The activity of recombinant luc was nearly ablated by incubation with either EPEC or Salmonella in a cell-free system. Activity was partially preserved by protease inhibitors, and immunoblot analysis showed a decreased amount and molecular weight of recombinant luc, suggesting protein degradation. Neither beta-gal nor CAT activity was altered by infection. Disruption of type III secretion prevented the loss of luc activity. We conclude that CAT or beta-gal, but not luc, can be used as reliable reporter genes to assess the impact of pathogenic microbes, especially those expressing type III secretion on host cell gene regulation.

  3. Effect of annealing time of an ice crystal on the activity of type III antifreeze protein.

    PubMed

    Takamichi, Manabu; Nishimiya, Yoshiyuki; Miura, Ai; Tsuda, Sakae

    2007-12-01

    Antifreeze proteins (AFPs) possess a unique ability to bind to a seed ice crystal to inhibit its growth. The strength of this binding has been evaluated by thermal hysteresis (TH). In this study, we examined the dependence of TH on experimental parameters, including cooling rate, annealing time, annealing temperature and the size of the seed ice crystal for an isoform of type III AFP from notched-fin eelpout (nfeAFP8). TH of nfeAFP8 dramatically decreased when using a fast cooling rate (0.20 degrees C x min(-1)). It also decreased with increasing seed crystal size under a slow cooling rate (0.01 degrees C x min(-1)), but such dependence was not detected under the fast cooling rate. TH was enhanced 1.4- and 2.5-fold when ice crystals were annealed for 3 h at 0.05 and 0.25 degrees C below T(m), respectively. After annealing for 2 h at 0.25 degrees C below T(m), TH activity showed marked dependence on the size of ice crystals. These results suggest that annealing of an ice crystal for 2-3 h significantly increased the TH value of type III AFP. Based on a proposed adsorption-inhibition model, we assume that type III AFP undergoes additional ice binding to the convex ice front over a 2-3 h time scale, which results in the TH dependence on the annealing time.

  4. Evidence for Langmuir Envelope Solitons in Solar Type III Burst Source Regions

    NASA Technical Reports Server (NTRS)

    Thejappa, G.; Goldstein, M. L.; MacDowall, R. J.; Papadopoulos, K.; Stone, R. G.

    1998-01-01

    We present observational evidence for the generation of Langmuir envelope solitons in the source regions of solar type III radio bursts. The solitons appear to be formed by electron beams which excite either the modulational instability or oscillating two-stream instability (OTSI). Millisecond data from the Ulysses Unified Radio and Plasma Wave Experiment (URAP) show that Langmuir waves associated with type III bursts occur as broad intense peaks with time scales ranging from 15 to 90 milliseconds (6 - 27 km). These broad field structures have the properties expected of Langmuir envelope solitons, viz.: the normalized peak energy densities, W(sub L)/n(sub e)T(sub e) approximately 10(exp -5), are well above the modulational instability threshold; the spatial scales, L, which range from 1 - 5 Langmuir wavelengths, show a high degree of inverse correlation with (W(sub L)/n(sub e)T(sub e))(sup 1/2); and the observed widths of these broad peaks agree well with the predicted widths of envelope solitons. We show that the orientation of the Langmuir field structures is random with respect to the ambient magnetic field, indicating that they are probably isotropic structures that have evolved from initially pancake-like solitons. These observations suggest that strong turbulence processes, such as the modulational instability or the OTSI, stabilize the electron beams that produce type III bursts.

  5. HVEM serial-section analysis of rabbit foliate taste buds: I. Type III cells and their synapses.

    PubMed

    Royer, S M; Kinnamon, J C

    1991-04-01

    Serially sectioned rabbit foliate taste buds were examined with high voltage electron microscopy (HVEM) and computer-assisted, three-dimensional reconstruction. This report focuses on the ultrastructure of the type III cells and their synapses with sensory nerve fibers. Type III cells have previously been proposed to be the primary gustatory receptor cells in taste buds of rabbits and other mammals. Within rabbit foliate taste buds, type III cells constitute a well-defined, easily recognizable class and are the only taste bud cells observed to form synapses with intragemmal nerve fibers. Among 18 type III cells reconstructed from serial sections, 11 formed from 1 to 6 synapses each with nerve fibers; 7 reconstructed type III cells formed no synapses. Examples of both convergence and divergence of synaptic input from type III cells onto nerve fibers were observed. The sizes of the active zones of the synapses and numbers of vesicles associated with the presynaptic membrane specializations were highly variable. Dense-cored vesicles 80-140 nm in diameter were often found among the 40-60 nm clear vesicles clustered at presynaptic sites. At some synapses, these large dense-cored vesicles appeared to be the predominant vesicle type. This observation suggests that there may be functionally different types of synapses in taste buds, distinguished by the prevalence of either clear or dense-cored vesicles. Previous investigations have indicated that the dense-cored vesicles in type III cells may be storage sites for biogenic amines.

  6. Multiplex real-time PCR SYBR Green for detection and typing of group III Clostridium botulinum.

    PubMed

    Anniballi, Fabrizio; Auricchio, Bruna; Delibato, Elisabetta; Antonacci, Monia; De Medici, Dario; Fenicia, Lucia

    2012-01-27

    Clostridium botulinum type C and type D belonging to the group III organisms, are mainly responsible for animal botulism outbreaks. Clinical signs alone are often insufficient to make a diagnosis of botulism and a laboratory confirmation is required. Laboratory confirmation can be performed by demonstrating the presence of botulinum neurotoxins in serum, gastrointestinal contents, liver, wound of sick or dead animals, or by demonstrating the presence of C. botulinum in gastrointestinal contents, liver, and wound. Demonstration of spores in gastrointestinal contents or tissue of animals with clinical signs indicative of botulism reinforces the clinical diagnosis. With the aim of detecting and typing C. botulinum group III organisms, a multiplex real-time PCR SYBR Green was developed and in-house validated. Selectivity, limit of detection, relative accuracy, relative specificity, relative sensitivity, and repeatability of the method were investigated. The multiplex real-time PCR SYBR green used showed a 100% selectivity, 100% relative accuracy, 100% relative specificity, 100% relative sensitivity and a limit of detection of 277 and 580 DNA copies for C. botulinum type C and C. botulinum type D, respectively. The method reported here represents a suitable tool for laboratory diagnosis of type C and D botulism and for testing a large number of samples collected during the animal botulism surveillance and prevention activities.

  7. Estimation of Group B Streptococcus Type III Polysaccharide-Specific Antibody Concentrations in Human Sera Is Antigen Dependent

    PubMed Central

    Bhushan, Reva; Anthony, Bascom F.; Frasch, Carl E.

    1998-01-01

    The presence of immunoglobulin G (IgG) antibodies against group B streptococcus (GBS) type III polysaccharide (PS) has been correlated with protection against GBS disease. The GBS type III PS is structurally similar to the pneumococcal type 14 PS, differing only in the presence of sialic acid residues. Four different preparations of GBS type III PS were evaluated for their specificity in enzyme-linked immunosorbent assay (ELISA): free PS, free PS mixed with methylated human serum albumin (mHSA), PS conjugated to biotin and PS conjugated to human serum albumin. Three groups of human sera were used to evaluate these PS preparations: sera from recipients of a GBS PS vaccine, sera from women receiving a GBS type III PS-tetanus toxoid conjugate vaccine, and sera from nonimmunized healthy women of childbearing age. Estimated antibody concentrations were different depending on the PS preparation used. Using any of the four preparations, we were able to measure ≤0.05 μg of IgG antibody to the GBS type III PS per ml. The specificity of the assay was determined by competitive inhibition with homologous and heterologous PS. The pneumococcal type 14 PS did not inhibit binding of antibody to the native GBS type III PS in sera from adults receiving the GBS PS vaccine or in sera from nonimmunized adults (except serum G9). The pneumococcal type 14 PS inhibited 50% in sera from recipients of GBS type III conjugate vaccine and in serum G9 when GBS type III PS conjugated to biotin or to HSA was used as antigen in ELISA. These data show that free GBS type III PS or PS mixed with mHSA is a sensitive and specific antigen for ELISA and that conjugation can alter the antigenic specificity of a PS. PMID:9826364

  8. Comparing comfort and wearability between Type III single-layered and double-layered EVA mouthguards.

    PubMed

    Kenyon, Brian J; Loos, Larry G

    2005-01-01

    This study compared two Type III ethylene vinyl acetate (EVA) mouthguards for wearability, comfort, fit, and patient preference. Twenty-two athletes each received two custom-fabricated athletic mouthguards, a single-layered vacuum-formed EVA mouthguard and a double-layered heat- and pressure-laminated EVA type. Athletes wore each type of mouthguard for a two-week period while playing basketball. At the end of each two-week period, the athletes completed questionnaires that evaluated 17 characteristics of each mouthguard type. Data were analyzed using the binomial test for small numbers. The double-layered heat- and pressure-laminated EVA mouthguard performed as well as or better than the single-layered vacuum-formed type in 14 of the 17 categories. There was a statistically significant patient preference for the double-layered heat- and pressure-laminated mouthguard.

  9. Dynamical structure of solar radio burst type III as evidence of energy of solar flares

    NASA Astrophysics Data System (ADS)

    Hamidi, Zety Sharizat Binti

    2013-11-01

    Observations of low frequency solar type III radio bursts associated with the ejection of plasma oscillations localized disturbance is due to excitation atoms in the plasma frequency incoherent radiations play a dominant role at the meter and decimeter wavelengths. Here, we report the results of the dynamical structure of solar flare type III that occurred on 9th March 2012 at National Space Centre, Sg Lang, Selangor, Malaysia by using the CALLISTO system. These bursts are associated with solar flare type M6 which suddenly ejected in the active region AR 1429 starting at 03:32 UT and ending at 05:00 UT with the peak at 04:12 UT. The observation showed an initial strong burst occurred due to strong signal at the beginning of the phase. We also found that both solar burst and flares tend to be a numerous on the same day and probability of chance coincidence is high. It is clearly seen that an impulsive lace burst was detected at 4:24 UT and it is more plausible that the energies are confined to the top of the loop when we compared with X-ray results. Associated with this event was type II with velocities 1285 km/s and type IV radio sweeps along with a full halo Coronal Mass Ejections (CMEs) first seen in SOHO/LASCO C2 imagery at 09/0426 Z. We concluded that the significance of study solar burst type III lies in the fact that the emission at decimetric wavelength comes from the role of magnetic field in active region that may provide the key to the energy release mechanism in a flare.

  10. Appurtenance Influence on Type III Hanford Single-Shell Tank Structural Integrity

    SciTech Connect

    Sanborn, Scott E.; Larsen, Brian M.; Julyk, Larry J.; Johnson, Kenneth I.

    2012-02-26

    The interim stabilized Hanford Single Shell Tanks (SSTs) are currently undergoing a state of the art analysis to assess the structural integrity of the waste storage tanks, for cleanup and closure operations, considering their adverse thermal histories and an updated seismic hazard for the Hanford Site near Richland, Washington. The SSTs contain a variety of ancillary pits, piping, piping supports, risers, equipment, and penetrations known as appurtenances. These appurtenances may alter the structural response and ultimately could affect the structural integrity of the SSTs. An important challenge to the structural analysis of the SSTs is determining the impact of these appurtenances on structural integrity. To achieve this, the various appurtenances were reviewed and bounding appurtenance configurations for SST Types II and III tank designs were analyzed using finite element software. The bounding configurations for the Type II tanks considered four heavy offset pits with a central pit with and without a 36-inch diameter central post-construction penetration and four 42-inch diameter offset penetrations. The bounding configuration for the Type III tanks is a tank with two heavy offset pits and one heavy central pit. For each bounding configuration two finite element models are developed: a seismic analysis model and a thermal and operating loads analysis (TOLA) model. The TOLA models include a Type II or III thermal history, concrete cracking and thermal degradation, reinforcement yielding, and soil plasticity. Additionally, operating loads such as internal waste pressure and concentrated and distributed soil surface loads are applied to the TOLA model. The seismic model treats the tank concrete as linear elastic based on the present day degraded concrete properties. Also, in the seismic model the soil is treated as linear elastic while special techniques are used in the soil above the tank dome and along the tank wall to avoid soil arching and achieve the proper

  11. Prominent Amphibian (Xenopus laevis) Tadpole Type III Interferon Response to the Frog Virus 3 Ranavirus

    PubMed Central

    Grayfer, Leon; De Jesús Andino, Francisco

    2015-01-01

    ABSTRACT Ranaviruses (Iridoviridae) are posing an increasing threat to amphibian populations, with anuran tadpoles being particularly susceptible to these viral infections. Moreover, amphibians are the most basal phylogenetic class of vertebrates known to possess both type I and type III interferon (IFN)-mediated immunity. Moreover, little is known regarding the respective roles of the IFN mediators in amphibian antiviral defenses. Accordingly, we transcriptionally and functionally compared the amphibian Xenopus laevis type I (IFN) and III (IFN-λ) IFNs in the context of infections by the ranavirus frog virus 3 (FV3). X. laevis IFN and IFN-λ displayed distinct tissue expression profiles. In contrast to our previous findings that X. laevis tadpoles exhibit delayed and modest type I IFN responses to FV3 infections compared to the responses of adults, here we report that tadpoles mount timely and robust type III IFN gene responses. Recombinant forms of these cytokines (recombinant X. laevis IFN [rXlIFN] and rXlIFN-λ) elicited antiviral gene expression in the kidney-derived A6 cell line as well as in tadpole leukocytes and tissues. However, rXlIFN-λ was less effective than rXlIFN in preventing FV3 replication in A6 cells and tadpoles and inferior at promoting tadpole survival. Intriguingly, FV3 impaired A6 cell and tadpole kidney type III IFN receptor gene expression. Furthermore, in A6 cultures rXlIFN-λ conferred equal or greater protection than rXlIFN against recombinant viruses deficient for the putative immune evasion genes, the viral caspase activation and recruitment domain (vCARD) or a truncated vIF-2α gene. Thus, in contrast to previous assumptions, tadpoles possess intact antiviral defenses reliant on type III IFNs, which are overcome by FV3 pathogens. IMPORTANCE Anuran tadpoles, including those of Xenopus laevis, are particularly susceptible to infection by ranavirus such as FV3. We investigated the respective roles of X. laevis type I and type III

  12. Neuronal merlin influences ERBB2 receptor expression on Schwann cells through neuregulin 1 type III signalling

    PubMed Central

    Schulz, Alexander; Kyselyova, Anna; Baader, Stephan L.; Jung, Marie Juliane; Zoch, Ansgar; Mautner, Victor-Felix

    2014-01-01

    Axonal surface proteins encompass a group of heterogeneous molecules, which exert a variety of different functions in the highly interdependent relationship between axons and Schwann cells. We recently revealed that the tumour suppressor protein merlin, mutated in the hereditary tumour syndrome neurofibromatosis type 2, impacts significantly on axon structure maintenance in the peripheral nervous system. We now report on a role of neuronal merlin in the regulation of the axonal surface protein neuregulin 1 important for modulating Schwann cell differentiation and myelination. Specifically, neuregulin 1 type III expression is reduced in sciatic nerve tissue of neuron-specific knockout animals as well as in biopsies from seven patients with neurofibromatosis type 2. In vitro experiments performed on both the P19 neuronal cell line and primary dorsal root ganglion cells demonstrate the influence of merlin on neuregulin 1 type III expression. Moreover, expression of ERBB2, a Schwann cell receptor for neuregulin 1 ligands is increased in nerve tissue of both neuron-specific merlin knockout animals and patients with neurofibromatosis type 2, demonstrating for the first time that axonal merlin indirectly regulates Schwann cell behaviour. Collectively, we have identified that neuronally expressed merlin can influence Schwann cell activity in a cell-extrinsic manner. PMID:24309211

  13. Towards a better understanding of magnetic exchange mediated by hydrogen bonds in Mn(III)/Fe(III) salen-type supramolecular dimers.

    PubMed

    Nemec, Ivan; Herchel, Radovan; Šilha, Tomáš; Trávníček, Zdeněk

    2014-11-01

    A thorough study of structural and magnetic properties was performed on a series of trinuclear and dinuclear Mn(III)/Fe(III) complexes consisting of [M(L4)(Solv)](+) and [Fe(CN)5(NO)](2-) moieties (M = Fe(III) or Mn(III), Solv = H2O or CH3OH, L4 = tetradentate salen-type ligands), in which dominant magnetic exchange is mediated by O(S)-H···O(Ph) hydrogen bonds in [M(L4)(Solv)](+)···[M(L4)(Solv)](+) supramolecular dimers. As deduced from magnetic analysis involving the determination of zero-field splitting (ZFS) parameters for Mn(III) and Fe(III) ions, as well as from comprehensive DFT calculations and modelling, it may be concluded that the strength of the magnetic exchange is correlated with the number of hydrogen bonds and with the O(Ph)···O(S) distance between the phenolic oxygen atom of the salen-type ligand (O(Ph)) and the oxygen atom of the solvent molecule coordinated to the adjacent metal atom (O(S)). PMID:25208575

  14. Reliable titration of filamentous bacteriophages independent of pIII fusion moiety and genome size by using trypsin to restore wild-type pIII phenotype.

    PubMed

    Løset, Geir Åge; Kristinsson, Solveig G; Sandlie, Inger

    2008-04-01

    Phage display holds a key position in the use of combinatorial library approaches for the purpose of protein engineering and discovery. However, modifying the pIII protein of the phage can severely and negatively influence the infectiousness of the phage particle. This concern is particularly relevant when large pIII fusions in combination with multivalent display systems are in use. We here describe the use of trypsin to restore wild-type pIII phenotype as a small modification to the standard titration protocol. The results show that the trypsin treatment has a very large but heterogeneous effect on the phage infection efficiency, depending on the pIII fusion domain and the valence of display.

  15. Expression and Quorum Sensing Regulation of Type III Secretion System Genes of Vibrio harveyi during Infection of Gnotobiotic Brine Shrimp.

    PubMed

    Ruwandeepika, H A Darshanee; Karunasagar, Indrani; Bossier, Peter; Defoirdt, Tom

    2015-01-01

    Type III secretion systems enable pathogens to inject their virulence factors directly into the cytoplasm of the host cells. The type III secretion system of Vibrio harveyi, a major pathogen of aquatic organisms and a model species in quorum sensing studies, is repressed by the quorum sensing master regulator LuxR. In this study, we found that during infection of gnotobiotic brine shrimp larvae, the expression levels of three type III secretion operons in V. harveyi increased within the first 12h after challenge and decreased again thereafter. The in vivo expression levels were highest in a mutant with a quorum sensing system that is locked in low cell density configuration (minimal LuxR levels) and lowest in a mutant with a quorum sensing system that is locked in the high cell density configuration (maximal LuxR levels), which is consistent with repression of type III secretion by LuxR. Remarkably, in vivo expression levels of the type III secretion system genes were much (> 1000 fold) higher than the in vitro expression levels, indicating that (currently unknown) host factors significantly induce the type III secretion system. Given the fact that type III secretion is energy-consuming, repression by the quorum sensing master regulators might be a mechanism to save energy under conditions where it does not provide an advantage to the cells. PMID:26636765

  16. Expression and Quorum Sensing Regulation of Type III Secretion System Genes of Vibrio harveyi during Infection of Gnotobiotic Brine Shrimp

    PubMed Central

    Ruwandeepika, H. A. Darshanee; Karunasagar, Indrani; Bossier, Peter; Defoirdt, Tom

    2015-01-01

    Type III secretion systems enable pathogens to inject their virulence factors directly into the cytoplasm of the host cells. The type III secretion system of Vibrio harveyi, a major pathogen of aquatic organisms and a model species in quorum sensing studies, is repressed by the quorum sensing master regulator LuxR. In this study, we found that during infection of gnotobiotic brine shrimp larvae, the expression levels of three type III secretion operons in V. harveyi increased within the first 12h after challenge and decreased again thereafter. The in vivo expression levels were highest in a mutant with a quorum sensing system that is locked in low cell density configuration (minimal LuxR levels) and lowest in a mutant with a quorum sensing system that is locked in the high cell density configuration (maximal LuxR levels), which is consistent with repression of type III secretion by LuxR. Remarkably, in vivo expression levels of the type III secretion system genes were much (> 1000 fold) higher than the in vitro expression levels, indicating that (currently unknown) host factors significantly induce the type III secretion system. Given the fact that type III secretion is energy-consuming, repression by the quorum sensing master regulators might be a mechanism to save energy under conditions where it does not provide an advantage to the cells. PMID:26636765

  17. G-rich, a Drosophila selenoprotein, is a Golgi-resident type III membrane protein

    SciTech Connect

    Chen, Chang Lan; Shim, Myoung Sup; Chung, Jiyeol; Yoo, Hyun-Seung; Ha, Ji Min; Kim, Jin Young; Choi, Jinmi; Zang, Shu Liang; Hou, Xiao; Carlson, Bradley A.; Hatfield, Dolph L.; Lee, Byeong Jae . E-mail: imbglmg@plaza.snu.ac.kr

    2006-10-06

    G-rich is a Drosophila melanogaster selenoprotein, which is a homologue of human and mouse SelK. Subcellular localization analysis using GFP-tagged G-rich showed that G-rich was localized in the Golgi apparatus. The fusion protein was co-localized with the Golgi marker proteins but not with an endoplasmic reticulum (ER) marker protein in Drosophila SL2 cells. Bioinformatic analysis of G-rich suggests that this protein is either type II or type III transmembrane protein. To determine the type of transmembrane protein experimentally, GFP-G-rich in which GFP was tagged at the N-terminus of G-rich, or G-rich-GFP in which GFP was tagged at the C-terminus of G-rich, were expressed in SL2 cells. The tagged proteins were then digested with trypsin, and analyzed by Western blot analysis. The results showed that the C-terminus of the G-rich protein was exposed to the cytoplasm indicating it is a type III microsomal membrane protein. G-rich is First selenoprotein identified in the Golgi apparatus.

  18. Management of Oehler's Type III Dens Invaginatus Using Cone Beam Computed Tomography.

    PubMed

    Ranganathan, Jaya; Rangarajan Sundaresan, Mohan Kumar; Ramasamy, Srinivasan

    2016-01-01

    Dens Invaginatus is a dental malformation that poses diagnostic difficulties in the clinical context. This anomaly may increase the risk of pulp disease and can potentially complicate endodontic procedure due to the aberrant root canal anatomy. Compared to conventional radiographs, three-dimensional images obtained with Cone Beam Computed Tomography (CBCT) are invaluable in the diagnosis of the extent of this anomaly and in the appropriate treatment planning. Oehler's classification (1957) for Dens Invaginatus (DI) into three types depending on the depth of the invagination has been used for treatment planning. Of the three types Type III DI is characterized by infolding of the enamel into the tooth up to the root apex and is considered as the most severe variant of DI and hence the most challenging to treat endodontically, due to the morphological complexities. This report describes a case of Oehler's Type III DI in a necrotic permanent maxillary lateral incisor in which CBCT images played a key role in diagnosis and treatment planning. The case was managed successfully by a combination of nonsurgical and surgical endodontic therapy with orthograde and retrograde thermoplastic gutta percha obturation. PMID:27069697

  19. Management of Oehler's Type III Dens Invaginatus Using Cone Beam Computed Tomography

    PubMed Central

    Ranganathan, Jaya; Rangarajan Sundaresan, Mohan Kumar; Ramasamy, Srinivasan

    2016-01-01

    Dens Invaginatus is a dental malformation that poses diagnostic difficulties in the clinical context. This anomaly may increase the risk of pulp disease and can potentially complicate endodontic procedure due to the aberrant root canal anatomy. Compared to conventional radiographs, three-dimensional images obtained with Cone Beam Computed Tomography (CBCT) are invaluable in the diagnosis of the extent of this anomaly and in the appropriate treatment planning. Oehler's classification (1957) for Dens Invaginatus (DI) into three types depending on the depth of the invagination has been used for treatment planning. Of the three types Type III DI is characterized by infolding of the enamel into the tooth up to the root apex and is considered as the most severe variant of DI and hence the most challenging to treat endodontically, due to the morphological complexities. This report describes a case of Oehler's Type III DI in a necrotic permanent maxillary lateral incisor in which CBCT images played a key role in diagnosis and treatment planning. The case was managed successfully by a combination of nonsurgical and surgical endodontic therapy with orthograde and retrograde thermoplastic gutta percha obturation. PMID:27069697

  20. Effect of type III antifreeze protein dilution and mutation on the growth inhibition of ice.

    PubMed Central

    DeLuca, C I; Chao, H; Sönnichsen, F D; Sykes, B D; Davies, P L

    1996-01-01

    Mutation of residues at the ice-binding site of type III antifreeze protein (AFP) not only reduced antifreeze activity as indicated by the failure to halt ice crystal growth, but also altered ice crystal morphology to produce elongated hexagonal bipyramids. In general, the c axis to a axis ratio of the ice crystal increased from approximately 2 to over 10 with the severity of the mutation. It also increased during ice crystal growth upon serial dilution of the wild-type AFP. This is in marked contrast to the behavior of the alpha-helical type I AFPs, where neither dilution nor mutation of ice-binding residues increases the c:a axial ratio of the ice crystal above the standard 3.3. We suggest that the ice crystal morphology produced by type III AFP and its mutants can be accounted for by the protein binding to the prism faces of ice and operating by step growth inhibition. In this model a decrease in the affinity of the AFP for ice leads to filling in of individual steps at the prism surfaces, causing the ice crystals to grow with a longer c:a axial ratio. Images FIGURE 3 FIGURE 4 PMID:8913575

  1. Matrix metalloproteinase-1 cleavage site recognition and binding in full-length human type III collagen.

    PubMed

    Williams, Kim E; Olsen, David R

    2009-07-01

    Matrix metalloproteinases (MMPs) are essential for normal collagen turnover, recovery from fibrosis, and vascular permeability. In fibrillar collagens, MMP-1, MMP-8, and MMP-13 cleave a specific glycine-isoleucine or glycine-leucine bond, despite the presence of this sequence in other parts of the protein. This cut site specificity has been hypothesized to arise from a unique, relaxed super-secondary structure in this area due to local hydroxyproline poor character. In this study we examined the mechanism of interaction and cleavage of human type III collagen by fibroblast MMP-1 by using a panel of recombinant human type III collagens (rhCIIIs) containing engineered sequences in the vicinity of the cleavage site. Native and recombinant type III collagens had similar biochemical and structural characteristics, as indicated by transmission electron microscopy, circular dichroism spectropolarimetry, melting temperature and hydroxyproline analysis. A single amino acid change at the I785 cleavage site to proline resulted in partial MMP-1 resistance, but cuts were found in novel sites in the original cleavage region. However, the replacement of five Y-position residues by proline in this region, regardless of I785 variation, conferred complete resistance to MMP-1, MMP-8, MMP-13, trypsin, and elastase. MMP-1 had a decreased specific activity towards and reduced cleavage rate of rhCIII I785P but a K(m) similar to wild-type. Despite the reductions in protease sensitivity, MMP-1 bound to all of the engineered rhCIIIs with comparable affinity, indicating that MMP-1 binding is not sufficient for cleavage. The relaxed tertiary structure in the MMP cleavage region may permit local collagen unwinding by MMP-1 that enables site-specific proteolysis.

  2. Directivity Patterns of Complex Solar Type III Radio Bursts: Stereoscopic Observations

    NASA Astrophysics Data System (ADS)

    Golla, T.; MacDowall, R. J.

    2014-12-01

    Complex solar type III-like radio bursts are a group of type III bursts that occur in association with slowly drifting type II radio bursts excited by coronal mass ejection (CME) driven shock waves. We presentsimultaneous observations of these radio bursts from the STEREO A, B and WIND spacecraft at low frequencies, located at different vantage points in the ecliptic plane. Using these stereoscopic observations, wedetermine the directivity of these complex radio bursts. We estimate the angles between the directions of the magnetic field at the sources and the lines connecting the source to the spacecraft (viewing angles) by assuming that the sources are located on the Parker spiral magnetic field lines emerging from the associated active regions into the spherically symmetric solar atmosphere. We estimate the normalized peak intensities of these bursts (directivity factors) at each spacecraft using their time profiles at each spacecraft. These observations indicate that the complex type III bursts can be divided into two groups: (1) bursts emitting into a very narrow cone centered around the tangent to the magnetic field, and (2) bursts emitting into a wider cone. We show that the bursts , which are emitted along the tangent to the spiral magnetic field lines at the source are very intense, and their intensities steadily fall as the viewing angles increase to higher values. We have developed a ray tracing code and computed the distributions of the trajectories of rays emitted at the fundamental and second harmonic of the electron plasma frequency. The comparison of the observed emission patterns with the computed distributions of the ray trajectories indicate that the intense bursts visible in a narrow range of angles around the magnetic field directions probably are emitted in the fundamental mode, whereas the relativelyweaker bursts visible to a wide range of angles are probably emitted in the harmonic mode.

  3. Solution structure of monomeric BsaL, the type III secretion needle protein of Burkholderia pseudomallei.

    PubMed

    Zhang, Lingling; Wang, Yu; Picking, Wendy L; Picking, William D; De Guzman, Roberto N

    2006-06-01

    Many gram-negative bacteria that are important human pathogens possess type III secretion systems as part of their required virulence factor repertoire. During the establishment of infection, these pathogens coordinately assemble greater than 20 different proteins into a macromolecular structure that spans the bacterial inner and outer membranes and, in many respects, resembles and functions like a syringe. This type III secretion apparatus (TTSA) is used to inject proteins into a host cell's membrane and cytoplasm to subvert normal cellular processes. The external portion of the TTSA is a needle that is composed of a single type of protein that is polymerized in a helical fashion to form an elongated tube with a central channel of 2-3 nm in diameter. TTSA needle proteins from a variety of bacterial pathogens share sequence conservation; however, no atomic structure for any TTSA needle protein is yet available. Here, we report the structure of a TTSA needle protein called BsaL from Burkholderia pseudomallei determined by nuclear magnetic resonance (NMR) spectroscopy. The central part of the protein assumes a helix-turn-helix core domain with two well-defined alpha-helices that are joined by an ordered, four-residue linker. This forms a two-helix bundle that is stabilized by interhelix hydrophobic contacts. Residues that flank this presumably exposed core region are not completely disordered, but adopt a partial helical conformation. The atomic structure of BsaL and its sequence homology with other TTSA needle proteins suggest potentially unique structural dynamics that could be linked with a universal mechanism for control of type III secretion in diverse gram-negative bacterial pathogens.

  4. Finite element analysis of three commonly used external fixation devices for treating Type III pilon fractures.

    PubMed

    Ramlee, Muhammad Hanif; Kadir, Mohammed Rafiq Abdul; Murali, Malliga Raman; Kamarul, Tunku

    2014-10-01

    Pilon fractures are commonly caused by high energy trauma and can result in long-term immobilization of patients. The use of an external fixator i.e. the (1) Delta, (2) Mitkovic or (3) Unilateral frame for treating type III pilon fractures is generally recommended by many experts owing to the stability provided by these constructs. This allows this type of fracture to heal quickly whilst permitting early mobilization. However, the stability of one fixator over the other has not been previously demonstrated. This study was conducted to determine the biomechanical stability of these external fixators in type III pilon fractures using finite element modelling. Three-dimensional models of the tibia, fibula, talus, calcaneus, navicular, cuboid, three cuneiforms and five metatarsal bones were reconstructed from previously obtained CT datasets. Bones were assigned with isotropic material properties, while the cartilage was assigned as hyperelastic springs with Mooney-Rivlin properties. Axial loads of 350 N and 70 N were applied at the tibia to simulate the stance and the swing phase of a gait cycle. To prevent rigid body motion, the calcaneus and metatarsals were fixed distally in all degrees of freedom. The results indicate that the model with the Delta frame produced the lowest relative micromovement (0.03 mm) compared to the Mitkovic (0.05 mm) and Unilateral (0.42 mm) fixators during the stance phase. The highest stress concentrations were found at the pin of the Unilateral external fixator (509.2 MPa) compared to the Mitkovic (286.0 MPa) and the Delta (266.7 MPa) frames. In conclusion, the Delta external fixator was found to be the most stable external fixator for treating type III pilon fractures.

  5. The type III secreted protein BspR regulates the virulence genes in Bordetella bronchiseptica.

    PubMed

    Kurushima, Jun; Kuwae, Asaomi; Abe, Akio

    2012-01-01

    Bordetella bronchiseptica is closely related with B. pertussis and B. parapertussis, the causative agents of whooping cough. These pathogenic species share a number of virulence genes, including the gene locus for the type III secretion system (T3SS) that delivers effector proteins. To identify unknown type III effectors in Bordetella, secreted proteins in the bacterial culture supernatants of wild-type B. bronchiseptica and an isogenic T3SS-deficient mutant were compared with iTRAQ-based, quantitative proteomic analysis method. BB1639, annotated as a hypothetical protein, was identified as a novel type III secreted protein and was designated BspR (Bordetella secreted protein regulator). The virulence of a BspR mutant (ΔbspR) in B. bronchiseptica was significantly attenuated in a mouse infection model. BspR was also highly conserved in B. pertussis and B. parapertussis, suggesting that BspR is an essential virulence factor in these three Bordetella species. Interestingly, the BspR-deficient strain showed hyper-secretion of T3SS-related proteins. Furthermore, T3SS-dependent host cell cytotoxicity and hemolytic activity were also enhanced in the absence of BspR. By contrast, the expression of filamentous hemagglutinin, pertactin, and adenylate cyclase toxin was completely abolished in the BspR-deficient strain. Finally, we demonstrated that BspR is involved in the iron-responsive regulation of T3SS. Thus, Bordetella virulence factors are coordinately but inversely controlled by BspR, which functions as a regulator in response to iron starvation.

  6. Alterations in biosynthetic accumulation of collagen types I and III during growth and morphogenesis of embryonic mouse salivary glands

    NASA Technical Reports Server (NTRS)

    Hardman, P.; Spooner, B. S.

    1992-01-01

    We examined the biosynthetic patterns of interstitial collagens in mouse embryonic submandibular and sublingual glands cultured in vitro. Rudiments explanted on day 13 of gestation and cultured for 24, 48, and 72 h all synthesized collagen types I, III, and V. However, while the total incorporation of label into collagenous proteins did not change over the three-day culture period, the rate of accumulation of newly synthesized types I and III did change. At 24 h, the ratio of newly synthesized collagen types I:III was approximately 2, whereas at 72 h, the ratio was approximately 5. These data suggest that collagen types I and III may be important in initiation of branching in this organ, but that type I may become dominant in the later stages of development and in maintenance of the adult organ.

  7. Complexation behavior of Eu(III), Tb(III), Tm(III), and Am(III) with three 1,10-phenanthroline-type ligands: insights from density functional theory.

    PubMed

    Yang, Yanqiu; Fang, Yu; Liu, Jun; Hu, Shiyuan; Hu, Sheng; Yang, Liang; Wang, Dawei; Zhang, Huabei; Luo, Shunzhong

    2015-07-01

    Extraction complexes of Eu(III), Tb(III), Tm(III), and Am(III) with three 1,10-phenanthroline-type ligands have been studied, primarily using density functional theory (DFT). The same accuracies and optimized structural geometries were obtained whether optimization of the [ML2(NO3)](2+) complexes was performed at the B3LYP/6-31G(d)/RECP or the MP2/6-31G(d)/RECP level of theory. Calculations carried out at the B3LYP/6-311G(d, p)/RECP level of theory indicated that solvation does not favor the formation of these complexes. Moreover, the ΔGg and ΔGsolv values for the reactions leading to the formation of [LnL2(NO3)](2+) complexes were seen to decrease with increasing atomic number of the lanthanide (from Eu to Tb to Tm). In addition, when a strongly hydrophobic benzo[e][1,2,4]triazine group was created in each ligand, ligand selectivity for actinides/lanthanides in acidic media improved. Even greater ligand selectivity for actinides/lanthanides in acidic media was obtained when a 5,6-diphenyl-1,2,4-triazine group was created in each ligand instead of a benzo[e][1,2,4]triazine group. Vibrational analysis and NMR spectroscopic analysis were also performed on all of the studied ligands and the metal complexes that included them. Further in-depth investigations should be undertaken in this field. PMID:26141789

  8. Beat-type Langmuir wave emissions associated with a type III solar radio burst: Evidence of parametric decay

    NASA Technical Reports Server (NTRS)

    Hospodarsky, G. B.; Gurnett, D. A.

    1995-01-01

    Recent measurements from the plasma wave instrument on the Galileo spacecraft have shown that Langmuir waves observed in conjunction with a type III solar radio burst contain many beat-type waveforms, with beat frequencies ranging from about 150 to 650 Hz. Strong evidence exists that the beat pattern is produced by two closely spaced narrowband components. The most likely candidates for these two waves are a beam-generated Langmuir wave and an oppositely propagating Langmuir wave produced by parametric decay. In the parametric decay process, nonlinear interactions cause the beam-driven Langmuir wave to decay into a Langmuir wave and a low-frequency ion sound wave. Comparisons of the observed beat frequency are in good agreement with theoretical predictions for a three-wave parametric decay process. Weak low-frequency emissions are also sometimes observed at the predicted frequency of the ion sound wave.

  9. Binding of heparin by type III domains and peptides from the carboxy terminal hep-2 region of fibronectin.

    PubMed

    Ingham, K C; Brew, S A; Migliorini, M M; Busby, T F

    1993-11-23

    The major sites of heparin binding by fibronectin are located in fragments of 30 or 40 kDa that contain type III modules 12 through 14 or 15. Various proteolytic or recombinant subfragments and several synthetic peptides derived from this region have been compared with respect to their binding to fluorescein-labeled heparin in solution. Binding was monitored by the change in fluorescence anisotropy at 25 degrees C and pH 7.4 in 0.02 M Tris buffer, alone (TB) or with 0.15M NaCl (TBS). A 23-kDa fragment containing III13 and III14 but lacking III12 had Kd values of 0.3 and 1.8 microM in TB, and TBS, respectively, indistinguishable from the 30-kDa parent. Fragments containing only module III13 bound 2-3-fold weaker than the parent while those containing only III14 bound 6-50-fold weaker depending on the ionic strength. Fragments containing only III12 or III15 failed to bind at all in TBS. A cationic peptide derived from the amino terminus of III13 and containing the Arg-Arg-Ala-Arg consensus sequence, whose integrity was shown by Barkalow and Schwarzbauer [Barkalow, F. J., & Schwarzbauer, J. E. (1991) J. Biol. Chem. 266, 7812-7818] to be critical, failed to bind in TBS but bound weakly in TB. Two additional cationic peptides derived from the middle and C-terminal regions of III14 showed similar behavior. Thus while the major determinant(s) of heparin binding are located in III13, those determinants are only active when part of a properly folded structure. Furthermore, module III13 when isolated had a slightly lower affinity than fragments containing both III13 and III14.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8241146

  10. Trabecular Metal Augments for the Management of Paprosky Type III Defects Without Pelvic Discontinuity.

    PubMed

    Grappiolo, Guido; Loppini, Mattia; Longo, Umile Giuseppe; Traverso, Francesco; Mazziotta, Giuseppe; Denaro, Vincenzo

    2015-06-01

    Fifty-five hips undergoing acetabular reconstruction with trabecular metal (TM)-coated cup and TM augments were reviewed at an average follow up of 53.7 months (36-91). Bony defects were Paprosky type IIIA in 42 and type IIIB without pelvic discontinuity in 13 hips. The average HHS increased from 40 (27-52) preoperatively to 90.5 (61-100) postoperatively (P<0.0001). Four (7.3%) of 55 hips underwent acetabular components revision: three cases of loosening (5.4%), and one of recurrent instability (1.8%) were reported. Survival rate at 2 and 5 years was 96.4% and 92.8%. In conclusion, the use of TM-coated cups and augments could be considered an effective management of Paprosky type III defects without pelvic discontinuity providing good clinical and radiographic outcomes in the mid term.

  11. The type III secretion system apparatus determines the intracellular niche of bacterial pathogens

    PubMed Central

    Du, Juan; Reeves, Analise Z.; Klein, Jessica A.; Twedt, Donna J.; Knodler, Leigh A.; Lesser, Cammie F.

    2016-01-01

    Upon entry into host cells, intracellular bacterial pathogens establish a variety of replicative niches. Although some remodel phagosomes, others rapidly escape into the cytosol of infected cells. Little is currently known regarding how professional intracytoplasmic pathogens, including Shigella, mediate phagosomal escape. Shigella, like many other Gram-negative bacterial pathogens, uses a type III secretion system to deliver multiple proteins, referred to as effectors, into host cells. Here, using an innovative reductionist-based approach, we demonstrate that the introduction of a functional Shigella type III secretion system, but none of its effectors, into a laboratory strain of Escherichia coli is sufficient to promote the efficient vacuole lysis and escape of the modified bacteria into the cytosol of epithelial cells. This establishes for the first time, to our knowledge, a direct physiologic role for the Shigella type III secretion apparatus (T3SA) in mediating phagosomal escape. Furthermore, although protein components of the T3SA share a moderate degree of structural and functional conservation across bacterial species, we show that vacuole lysis is not a common feature of T3SA, as an effectorless strain of Yersinia remains confined to phagosomes. Additionally, by exploiting the functional interchangeability of the translocator components of the T3SA of Shigella, Salmonella, and Chromobacterium, we demonstrate that a single protein component of the T3SA translocon—Shigella IpaC, Salmonella SipC, or Chromobacterium CipC—determines the fate of intracellular pathogens within both epithelial cells and macrophages. Thus, these findings have identified a likely paradigm by which the replicative niche of many intracellular bacterial pathogens is established. PMID:27078095

  12. LOFAR tied-array imaging of Type III solar radio bursts

    NASA Astrophysics Data System (ADS)

    Morosan, D. E.; Gallagher, P. T.; Zucca, P.; Fallows, R.; Carley, E. P.; Mann, G.; Bisi, M. M.; Kerdraon, A.; Konovalenko, A. A.; MacKinnon, A. L.; Rucker, H. O.; Thidé, B.; Magdalenić, J.; Vocks, C.; Reid, H.; Anderson, J.; Asgekar, A.; Avruch, I. M.; Bentum, M. J.; Bernardi, G.; Best, P.; Bonafede, A.; Bregman, J.; Breitling, F.; Broderick, J.; Brüggen, M.; Butcher, H. R.; Ciardi, B.; Conway, J. E.; de Gasperin, F.; de Geus, E.; Deller, A.; Duscha, S.; Eislöffel, J.; Engels, D.; Falcke, H.; Ferrari, C.; Frieswijk, W.; Garrett, M. A.; Grießmeier, J.; Gunst, A. W.; Hassall, T. E.; Hessels, J. W. T.; Hoeft, M.; Hörandel, J.; Horneffer, A.; Iacobelli, M.; Juette, E.; Karastergiou, A.; Kondratiev, V. I.; Kramer, M.; Kuniyoshi, M.; Kuper, G.; Maat, P.; Markoff, S.; McKean, J. P.; Mulcahy, D. D.; Munk, H.; Nelles, A.; Norden, M. J.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pandey, V. N.; Pietka, G.; Pizzo, R.; Polatidis, A. G.; Reich, W.; Röttgering, H.; Scaife, A. M. M.; Schwarz, D.; Serylak, M.; Smirnov, O.; Stappers, B. W.; Stewart, A.; Tagger, M.; Tang, Y.; Tasse, C.; Thoudam, S.; Toribio, C.; Vermeulen, R.; van Weeren, R. J.; Wucknitz, O.; Yatawatta, S.; Zarka, P.

    2014-08-01

    Context. The Sun is an active source of radio emission which is often associated with energetic phenomena such as solar flares and coronal mass ejections (CMEs). At low radio frequencies (<100 MHz), the Sun has not been imaged extensively because of the instrumental limitations of previous radio telescopes. Aims: Here, the combined high spatial, spectral, and temporal resolution of the LOw Frequency ARray (LOFAR) was used to study solar Type III radio bursts at 30-90 MHz and their association with CMEs. Methods: The Sun was imaged with 126 simultaneous tied-array beams within ≤5 R⊙ of the solar centre. This method offers benefits over standard interferometric imaging since each beam produces high temporal (~83 ms) and spectral resolution (12.5 kHz) dynamic spectra at an array of spatial locations centred on the Sun. LOFAR's standard interferometric output is currently limited to one image per second. Results: Over a period of 30 min, multiple Type III radio bursts were observed, a number of which were found to be located at high altitudes (~4 R⊙ from the solar center at 30 MHz) and to have non-radial trajectories. These bursts occurred at altitudes in excess of values predicted by 1D radial electron density models. The non-radial high altitude Type III bursts were found to be associated with the expanding flank of a CME. Conclusions: The CME may have compressed neighbouring streamer plasma producing larger electron densities at high altitudes, while the non-radial burst trajectories can be explained by the deflection of radial magnetic fields as the CME expanded in the low corona. Movie associated to Fig. 2 is available in electronic form at http://www.aanda.org

  13. The type III secretion system apparatus determines the intracellular niche of bacterial pathogens.

    PubMed

    Du, Juan; Reeves, Analise Z; Klein, Jessica A; Twedt, Donna J; Knodler, Leigh A; Lesser, Cammie F

    2016-04-26

    Upon entry into host cells, intracellular bacterial pathogens establish a variety of replicative niches. Although some remodel phagosomes, others rapidly escape into the cytosol of infected cells. Little is currently known regarding how professional intracytoplasmic pathogens, including Shigella, mediate phagosomal escape. Shigella, like many other Gram-negative bacterial pathogens, uses a type III secretion system to deliver multiple proteins, referred to as effectors, into host cells. Here, using an innovative reductionist-based approach, we demonstrate that the introduction of a functional Shigella type III secretion system, but none of its effectors, into a laboratory strain of Escherichia coli is sufficient to promote the efficient vacuole lysis and escape of the modified bacteria into the cytosol of epithelial cells. This establishes for the first time, to our knowledge, a direct physiologic role for the Shigella type III secretion apparatus (T3SA) in mediating phagosomal escape. Furthermore, although protein components of the T3SA share a moderate degree of structural and functional conservation across bacterial species, we show that vacuole lysis is not a common feature of T3SA, as an effectorless strain of Yersinia remains confined to phagosomes. Additionally, by exploiting the functional interchangeability of the translocator components of the T3SA of Shigella, Salmonella, and Chromobacterium, we demonstrate that a single protein component of the T3SA translocon-Shigella IpaC, Salmonella SipC, or Chromobacterium CipC-determines the fate of intracellular pathogens within both epithelial cells and macrophages. Thus, these findings have identified a likely paradigm by which the replicative niche of many intracellular bacterial pathogens is established. PMID:27078095

  14. Electro-optical properties characterization of fish type III antifreeze protein.

    PubMed

    Salvay, Andrés G; Santos, Javier; Howard, Eduardo I

    2007-12-01

    Antifreeze proteins (AFPs) are ice-binding proteins that depress the freezing point of water in a non-colligative manner without a significant modification of the melting point. Found in the blood and tissues of some organisms (such as fish, insects, plants, and soil bacteria), AFPs play an important role in subzero temperature survival. Fish Type III AFP is present in members of the subclass Zoarcoidei. AFPIII are small 7-kDa-or 14-kDa tandem-globular proteins. In the present work, we study the behavior of several physical properties, such as the low-frequency dielectric permittivity spectrum, circular dichroism, and electrical conductivity of Fish Type III AFP solutions measured at different concentrations. The combination of the information obtained from these measurements could be explained through the formation of AFP molecular aggregates or, alternatively, by the existence of some other type of interparticle interactions. Thermal stability and electro-optical behavior, when proteins are dissolved in deuterated water, were also investigated.

  15. Electro-Optical Properties Characterization of Fish Type III Antifreeze Protein

    PubMed Central

    Salvay, Andrés G.; Santos, Javier

    2008-01-01

    Antifreeze proteins (AFPs) are ice-binding proteins that depress the freezing point of water in a non-colligative manner without a significant modification of the melting point. Found in the blood and tissues of some organisms (such as fish, insects, plants, and soil bacteria), AFPs play an important role in subzero temperature survival. Fish Type III AFP is present in members of the subclass Zoarcoidei. AFPIII are small 7-kDa—or 14-kDa tandem—globular proteins. In the present work, we study the behavior of several physical properties, such as the low-frequency dielectric permittivity spectrum, circular dichroism, and electrical conductivity of Fish Type III AFP solutions measured at different concentrations. The combination of the information obtained from these measurements could be explained through the formation of AFP molecular aggregates or, alternatively, by the existence of some other type of interparticle interactions. Thermal stability and electro-optical behavior, when proteins are dissolved in deuterated water, were also investigated. PMID:19669526

  16. Electron beam induced current in InSb-InAs nanowire type-III heterostructures

    NASA Astrophysics Data System (ADS)

    Chen, C. Y.; Shik, A.; Pitanti, A.; Tredicucci, A.; Ercolani, D.; Sorba, L.; Beltram, F.; Ruda, H. E.

    2012-08-01

    InSb-InAs nanowire heterostructure diodes investigated by electron beam induced current (EBIC) demonstrate an unusual spatial profile where the sign of the EBIC signal changes in the vicinity of the heterointerface. A qualitative explanation confirmed by theoretical calculations is based on the specific band diagram of the structure representing a type-III heterojunction with an accumulation layer in InAs. The sign of the EBIC signal depends on the specific parameters of this layer. In the course of measurements, the diffusion length of holes in InAs and its temperature dependence are also determined.

  17. Tyrosinemia type III: diagnosis and ten-year follow-up.

    PubMed

    Cerone, R; Holme, E; Schiaffino, M C; Caruso, U; Maritano, L; Romano, C

    1997-09-01

    Tyrosinemia type III, caused by deficiency of 4-hydroxyphenylpyruvate dioxygenase, is a rare disorder of tyrosine catabolism. Primary 4-hydroxyphenylpyruvate dioxygenase deficiency has been described in only three patients. The biochemical phenotype shows hypertyrosinemia and elevated urinary excretion of 4-hydroxyphenyl derivatives. We report the clinical and biochemical findings and the results of long-term follow-up in a new patient with this disorder presenting with severe mental retardation and neurological abnormalities. The clinical phenotype is compared with those reported in the three previously described patients.

  18. Type III Dens Invaginatus with an Associated Cyst: A Case Report and Literature Review

    PubMed Central

    Thejokrishna, P

    2011-01-01

    Dens invaginatus (dens in dente) is a rare malformation with a widely varied morphology. An unusual presentation of a type III dens invaginatus affecting a conical shaped permanent lateral incisor in an 8-year-old female patient is reported. The presence of a pulp stone and a periapical radiolucency further added onto the complexity of the case. The etiology, pathophysiology, association with other dental anomalies as well as the challenges in management of this anomaly are discussed. An extensive literature review is also presented.

  19. Developmental Defects in a Caenorhabditis elegans Model for Type III Galactosemia

    PubMed Central

    Brokate-Llanos, Ana M.; Monje, José M.; Murdoch, Piedad del Socorro; Muñoz, Manuel J.

    2014-01-01

    Type III galactosemia is a metabolic disorder caused by reduced activity of UDP-galactose-4-epimerase, which participates in galactose metabolism and the generation of various UDP-sugar species. We characterized gale-1 in Caenorhabditis elegans and found that a complete loss-of-function mutation is lethal, as has been hypothesized for humans, whereas a nonlethal partial loss-of-function allele causes a variety of developmental abnormalities, likely resulting from the impairment of the glycosylation process. We also observed that gale-1 mutants are hypersensitive to galactose as well as to infections. Interestingly, we found interactions between gale-1 and the unfolded protein response. PMID:25298520

  20. [Glycogenosis type III and Crohn disease with associated ankylopoietic spondylitis and secondary amyloidosis. An unusual coincidence].

    PubMed

    Sánchez Creus, P; Martínez López de Letona, J; Ladero Quesada, J M; Gilsanz Rico, G

    1994-12-01

    We present a member of a family with glycogen deposit disease (GDD) type III (Forbes-Cori's disease) confirmed postmortem through enzymatic analysis of the hepatic and muscular tissues, coinciding with a Crohn's disease associated to ankylopoietic spondylitis, with final development of an extended secondary amiloidosis, all of these diagnosis established in life of the patient and verified in necropsy. We comment this rare finding, the absence of similar cases in the bibliography and the fortuitous nature of this association given the impossibility to suggest another relationship.

  1. Expression, purification and crystallization of a fungal type III polyketide synthase that produces the csypyrones

    PubMed Central

    Yang, Dengfeng; Mori, Takahiro; Matsui, Takashi; Hashimoto, Makoto; Morita, Hiroyuki; Fujii, Isao; Abe, Ikuro

    2014-01-01

    CsyB from Aspergillus oryzae is a novel type III polyketide synthase that catalyzes the formation of csypyrone B1 [4-(3-acetyl-4-hydroxy-2-oxo-2H-pyran-6-yl)butyric acid] from fatty acyl-CoA, malonyl-CoA and acetoacetyl-CoA. Recombinant CsyB expressed in Escherichia coli was crystallized by the sitting-drop vapour-diffusion method. The crystals belonged to space P21, with unit-cell parameters a = 70.0, b = 104.8, c = 73.5 Å, β = 114.4°. PMID:24915080

  2. Congenital Type III von Willebrand's disease unmasked by hypothyroidism in a Shetland sheepdog.

    PubMed

    Scuderi, Margaret; Bessey, Lauren; Snead, Elisabeth; Burgess, Hilary; Carr, Anthony

    2015-09-01

    A 7-year-old, spayed female Shetland sheepdog had sudden onset of right-sided epistaxis. Diagnostic tests revealed Type III von Willebrand's disease and primary hypothyroidism leading to an acute hypothyroid crisis and acquired factor VIII (FVIII) deficiency. Levothyroxine therapy normalized the serum thyroxine and FVIII concentrations. The delayed onset of disease and the reversible FVIII deficiency that was corrected with levothyroxine therapy, support a role for hypothyroidism in the pathogenesis of this dog's sudden bleeding tendency as has been seen with hypothyroidism in humans. PMID:26347307

  3. Congenital Type III von Willebrand's disease unmasked by hypothyroidism in a Shetland sheepdog.

    PubMed

    Scuderi, Margaret; Bessey, Lauren; Snead, Elisabeth; Burgess, Hilary; Carr, Anthony

    2015-09-01

    A 7-year-old, spayed female Shetland sheepdog had sudden onset of right-sided epistaxis. Diagnostic tests revealed Type III von Willebrand's disease and primary hypothyroidism leading to an acute hypothyroid crisis and acquired factor VIII (FVIII) deficiency. Levothyroxine therapy normalized the serum thyroxine and FVIII concentrations. The delayed onset of disease and the reversible FVIII deficiency that was corrected with levothyroxine therapy, support a role for hypothyroidism in the pathogenesis of this dog's sudden bleeding tendency as has been seen with hypothyroidism in humans.

  4. The effect of initial conditions on the electromagnetic radiation generation in type III solar radio bursts

    SciTech Connect

    Schmitz, H.; Tsiklauri, D.

    2013-06-15

    Extensive particle-in-cell simulations of fast electron beams injected in a background magnetised plasma with a decreasing density profile were carried out. These simulations were intended to further shed light on a newly proposed mechanism for the generation of electromagnetic waves in type III solar radio bursts [D. Tsiklauri, Phys. Plasmas, 18, 052903 (2011)]. The numerical simulations were carried out using different density profiles and fast electron distribution functions. It is shown that electromagnetic L and R modes are excited by the transverse current, initially imposed on the system. In the course of the simulations, no further interaction of the electron beam with the background plasma could be observed.

  5. Connection between ambient density fluctuations and clumpy Langmuir waves in type III radio sources

    NASA Technical Reports Server (NTRS)

    Robinson, P. A.; Cairns, I. H.; Gurnett, D. A.

    1992-01-01

    A recent stochastic-growth theory of clumpy Langmuir waves in type III sources is shown to imply that the clumps will have the same size distribution as the ambient low-frequency density fluctuations in the solar wind. Spectral analysis of Langmuir-wave time series from the ISEE 3 plasma wave instrument confirms this prediction to within the uncertainties in the spectra. The smallest Langmuir clump size is inferred to be in the range 0.4-30 km in general, and 2-30 km for beam-resonant waves, and it is concluded that the diffusion of waves in the source is anomalous.

  6. Localization, by linkage analysis, of the cystinuria type III gene to chromosome 19q13.1

    SciTech Connect

    Bisceglia, L.; Totaro, A.; Melchionda, S.

    1997-03-01

    Cystinuria is an autosomal recessive aminoaciduria in which three urinary phenotypes (I, II, and III) have been described. An amino acid transporter gene, SLC3A1 (formerly rBAT), was found to be responsible for this disorder. Mutational and linkage analysis demonstrated the presence of genetic heterogeneity in which the SLC3A1 gene is responsible for type I cystinuria but not for type II or type III. In this study, we report the identification of the cystinuria type III locus on the long arm of chromosome 19 (19q13.1), obtained after a genomewide search. Pairwise linkage analysis in a series of type III or type II families previously excluded from linkage to the cystinuria type I locus (SLC3A1 gene) revealed a significant maximum LOD score (Z{sub max}) of 13.11 at a maximum recombination fraction ({theta}{sub max}) of .00, with marker D19S225. Multipoint linkage analysis performed with the use of additional markers from the region placed the cystinuria type III locus between D19S414 and D19S220. Preliminary data on type II families also seem to place the disease locus for this rare type of cystinuria at 19q13.1 (significant Z{sub max} = 3.11 at {theta}{sub max} of .00, with marker D19S225). 33 refs., 2 figs., 1 tab.

  7. Collagen Type III and VI Turnover in Response to Long-Term Immobilization

    PubMed Central

    Sun, Shu; Henriksen, Kim; Karsdal, Morten A.; Byrjalsen, Inger; Rittweger, Jörn; Armbrecht, Gabriele; Belavy, Daniel L.; Felsenberg, Dieter; Nedergaard, Anders F.

    2015-01-01

    Background Muscle mass and function are perturbed by immobilization and remobilization. When muscle mass changes, the quality and quantity of the extracellular matrix protein, particularly the collagens, change with it. In this study, we investigated the temporal profile of three peptide biomarkers derived from turnover of collagen type III and type VI in a long-term immobilization and remobilization study. We also compared individual biomarker levels with Lean body Mass (LBM) and changes therein, hypothesizing that these biomarkers would be biomarkers of the remodeling processes associated with immobilization and/or remobilization. Methods In the Berlin bed rest study, 20 young men were recruited and randomly assigned to 8-week’s strict bed rest with or without resistive vibration exercise countermeasure. We measured three neo-epitope ELISA kits in the serum samples of this study: Pro-C3, measured the synthesis of collagen type III; Pro-C6, measured the synthesis of collagen type VI; and C6M measured the degradation of collagen type VI induced by MMP-2 and MMP-9 cleavage. Results Pro-C3 and Pro-C6 biomarkers are up-regulated with both immobilization and remobilization, whereas C6M is hardly affected at all. We found that Pro-C3 and C6M levels are related to LBM at baseline and that high levels of Pro-C6 are associated with smaller changes in muscle mass during both immobilization and remobilization. Conclusion The Pro-C3 and–C6 biomarkers change likely reflect remodeling changes in response to unloading or reloading, whereas C6M does not appear to respond to unloading. Pro-C3 and C6M levels correlate with LBM at baseline, while Pro-C6 is related to the anabolic and catabolic responses to unloading and reloading. PMID:26641456

  8. Type III tibial avulsion fracture with associated anterior cruciate ligament injury: Report of two cases in adults.

    PubMed

    Levy, H J; Fowble, V A

    2001-05-01

    Tibial spine avulsion fractures are more common in children than adults. Many reports have provided classification and treatment options, including fixation for displaced type III fractures. However, long-term follow-up on injury to the anterior cruciate ligament and knee joint stability in adults is not well documented. We present 2 cases of type III tibial avulsion fractures in adults with associated interstitial injury to the anterior cruciate ligament. Primary anterior cruciate ligament reconstruction was performed in both patients.

  9. Structure-function relationships within Keppler-type antitumor ruthenium(III) complexes: the case of 2-aminothiazolium[trans-tetrachlorobis(2-aminothiazole)ruthenate(III)].

    PubMed

    Mura, Pasquale; Piccioli, Francesca; Gabbiani, Chiara; Camalli, Mercedes; Messori, Luigi

    2005-07-11

    Keppler-type ruthenium(III) complexes exhibit promising antitumor properties. We report here a study of 2-aminothiazolium[trans-tetrachlorobis(2-aminothiazole)ruthenate(III)], both in the solid state and in solution. The crystal structure has been solved and found to exhibit classical features. Important solvatochromic effects were revealed. Notably, we observed that introduction of an amino group in position 2 greatly accelerates chloride hydrolysis compared to the thiazole analogue; this latter finding may be of interest for a fine-tuning of the reactivity of these novel metallodrugs.

  10. Solar Cycle Variations of the Occurrence of Coronal Type III Radio Bursts and a New Solar Activity Index

    NASA Astrophysics Data System (ADS)

    Lobzin, V. V.; Cairns, I. H.; Robinson, P. A.

    2011-12-01

    The results of studies of solar cycle variations of the occurrence rate of coronal type III radio bursts are presented. The radio spectra are provided by the Learmonth Solar Radio Observatory (Western Australia), part of the USAF Radio Solar Telescope Network (RSTN). It is found that the occurrence rate of type III bursts strongly correlates with solar activity. However, the profiles for the smoothed type III burst occurrence rate differ considerably from those for the sunspot number, 10.7 cm solar radio flux, and solar flare index. The type III burst occurrence rate (T3BOR) is proposed as a new index of solar activity. T3BOR provides complementary information about solar activity and should be useful in different studies including solar cycle predictions and searches for different periodicities in solar activity. This index can be estimated from daily results of the Automated Radio Burst Identification System (ARBIS). Access to data from other RSTN sites will allow processing 24-hour radio spectra in near-real time and estimating true daily values of this index. It is also shown that coronal type III bursts can even occur when there are no visible sunspots on the Sun. However, no evidence is found that the bursts are not associated with active regions. It is also concluded that the type III burst productivity of active regions exhibits solar cycle variations.

  11. Diverse evolutionary mechanisms shape the type III effector virulence factor repertoire in the plant pathogen Pseudomonas syringae.

    PubMed Central

    Rohmer, Laurence; Guttman, David S; Dangl, Jeffery L

    2004-01-01

    Many gram-negative pathogenic bacteria directly translocate effector proteins into eukaryotic host cells via type III delivery systems. Type III effector proteins are determinants of virulence on susceptible plant hosts; they are also the proteins that trigger specific disease resistance in resistant plant hosts. Evolution of type III effectors is dominated by competing forces: the likely requirement for conservation of virulence function, the avoidance of host defenses, and possible adaptation to new hosts. To understand the evolutionary history of type III effectors in Pseudomonas syringae, we searched for homologs to 44 known or candidate P. syringae type III effectors and two effector chaperones. We examined 24 gene families for distribution among bacterial species, amino acid sequence diversity, and features indicative of horizontal transfer. We assessed the role of diversifying and purifying selection in the evolution of these gene families. While some P. syringae type III effectors were acquired recently, others have evolved predominantly by descent. The majority of codons in most of these genes were subjected to purifying selection, suggesting selective pressure to maintain presumed virulence function. However, members of 7 families had domains subject to diversifying selection. PMID:15280247

  12. SOLAR CYCLE VARIATIONS OF THE OCCURRENCE OF CORONAL TYPE III RADIO BURSTS AND A NEW SOLAR ACTIVITY INDEX

    SciTech Connect

    Lobzin, Vasili; Cairns, Iver H.; Robinson, Peter A.

    2011-07-20

    This Letter presents the results of studies of solar cycle variations of the occurrence rate of coronal type III radio bursts. The radio spectra are provided by the Learmonth Solar Radio Observatory (Western Australia), part of the USAF Radio Solar Telescope Network (RSTN). It is found that the occurrence rate of type III bursts strongly correlates with solar activity. However, the profiles for the smoothed type III burst occurrence rate differ considerably from those for the sunspot number, 10.7 cm solar radio flux, and solar flare index. The type III burst occurrence rate (T3BOR) is proposed as a new index of solar activity. T3BOR provides complementary information about solar activity and should be useful in different studies including solar cycle predictions and searches for different periodicities in solar activity. This index can be estimated from daily results of the Automated Radio Burst Identification System. Access to data from other RSTN sites will allow processing 24 hr radio spectra in near-real time and estimating true daily values of this index. It is also shown that coronal type III bursts can even occur when there are no visible sunspots on the Sun. However, no evidence is found that the bursts are not associated with active regions. It is also concluded that the type III burst productivity of active regions exhibits solar cycle variations.

  13. Role of NSO compounds during primary cracking of a Type II kerogen and a Type III lignite

    USGS Publications Warehouse

    Behar, F.; Lorant, F.; Lewan, M.

    2008-01-01

    The aim of this work is to follow the generation of NSO compounds during the artificial maturation of an immature Type II kerogen and a Type III lignite in order to determine the different sources of the petroleum potential during primary cracking. Experiments were carried out in closed system pyrolysis in the temperature range from 225 to 350 ??C. Two types of NSOs were recovered: one is soluble in n-pentane and the second in dichloromethane. A kinetic scheme was optimised including both kerogen and NSO cracking. It was validated by complementary experiments carried out on isolated asphaltenes generated from the Type II kerogen and on the total n-pentane and DCM extracts generated from the Type III lignite. Results show that kerogen and lignite first decompose into DCM NSOs with minor generation of hydrocarbons. Then, the main source of petroleum potential originates from secondary cracking of both DCM and n-pentane NSOs through successive decomposition reactions. These results confirm the model proposed by Tissot [Tissot, B., 1969. Premie??res donne??es sur les me??canismes et la cine??tique de la formation du pe??trole dans les bassins se??dimentaires. Simulation d'un sche??ma re??actionnel sur ordinateur. Oil and Gas Science and Technology 24, 470-501] in which the main source of hydrocarbons is not the insoluble organic matter, but the NSO fraction. As secondary cracking of the NSOs largely overlaps that of the kerogen, it was demonstrated that bulk kinetics in open system is a result of both kerogen and NSO cracking. Thus, another kinetic scheme for primary cracking in open system was built as a combination of kerogen and NSO cracking. This new kinetic scheme accounts for both the rate and amounts of hydrocarbons generated in a closed pyrolysis system. Thus, the concept of successive steps for hydrocarbon generation is valid for the two types of pyrolysis system and, for the first time, a common kinetic scheme is available for extrapolating results to natural

  14. The insect endosymbiont Sodalis glossinidius utilizes a type III secretion system for cell invasion.

    PubMed

    Dale, C; Young, S A; Haydon, D T; Welburn, S C

    2001-02-13

    Sodalis glossinidius is a maternally transmitted secondary endosymbiont residing intracellularly in tissues of the tsetse flies, Glossina spp. In this study, we have used Tn5 mutagenesis and a negative selection procedure to derive a S. glossinidius mutant that is incapable of invading insect cells in vitro and is aposymbiotic when microinjected into tsetse. This mutant strain harbors Tn5 integrated into a chromosomal gene sharing high sequence identity with a type III secretion system invasion gene (invC) previously identified in Salmonella enterica. With the use of degenerate PCR, we have amplified a further six Sodalis inv/spa genes sharing high sequence identity with type III secretion system genes encoded by Salmonella pathogenicity island 1. Phylogenetic reconstructions based on the inv/spa genes of Sodalis and other members of the family Enterobacteriaceae have consistently identified a well-supported clade containing Sodalis and the enteric pathogens Shigella and Salmonella. These results suggest that Sodalis may have evolved from an ancestor with a parasitic intracellular lifestyle, possibly a latter-day entomopathogen. These observations lend credence to a hypothesis suggesting that vertically transmitted mutualistic endosymbionts evolve from horizontally transmitted parasites through a parasitism-mutualism continuum.

  15. Oleanolic Acid Induces the Type III Secretion System of Ralstonia solanacearum.

    PubMed

    Wu, Dousheng; Ding, Wei; Zhang, Yong; Liu, Xuejiao; Yang, Liang

    2015-01-01

    Ralstonia solanacearum, the causal agent of bacterial wilt, can naturally infect a wide range of host plants. The type III secretion system (T3SS) is a major virulence determinant in this bacterium. Studies have shown that plant-derived compounds are able to inhibit or induce the T3SS in some plant pathogenic bacteria, though no specific T3SS inhibitor or inducer has yet been identified in R. solanacearum. In this study, a total of 50 different compounds were screened and almost half of them (22 of 50) significantly inhibited or induced the T3SS expression of R. solanacearum. Based on the strong induction activity on T3SS, the T3SS inducer oleanolic acid (OA) was chosen for further study. We found that OA induced the expression of T3SS through the HrpG-HrpB pathway. Some type III effector genes were induced in T3SS inducing medium supplemented with OA. In addition, OA targeted only the T3SS and did not affect other virulence determinants. Finally, we observed that induction of T3SS by OA accelerated disease progress on tobacco. Overall our results suggest that plant-derived compounds are an abundant source of R. solanacearum T3SS regulators, which could prove useful as tools to interrogate the regulation of this key virulence pathway. PMID:26732647

  16. Type III mixed cryoglobulinemia and antiphospholipid syndrome in a patient with partial DiGeorge syndrome.

    PubMed

    Chang, Alice D; Tachdjian, Raffi; Gallagher, Kerry; McCurdy, Deborah K; Lassman, Charles; Stiehm, E Richard; Yadin, Ora

    2006-01-01

    We studied a 14 year-old boy with partial DiGeorge syndrome (DGS), status post complete repair of Tetralogy of Fallot, who developed antiphospholipid syndrome (APS) and type III mixed cryoglobulinemia. He presented with recurrent fever and dyspnea upon exertion secondary to right pulmonary embolus on chest computed tomography (CT). Coagulation studies revealed homozygous methylene tetrahydrofolate reductase 677TT mutations, elevated cardiolipin IgM antibodies, and elevated beta(2)-glycoprotein I IgM antibodies. Infectious work-up revealed only positive anti-streptolysin O (ASO) and anti-DNAse B titers. Autoimmune studies showed strongly positive anti-platelet IgM, elevated rheumatoid factor (RF), and positive cryocrit. Renal biopsy for evaluation of proteinuria and hematuria showed diffuse proliferative glomerulonephritis (DPGN) with membranoproliferative features consistent with cryoglobulinemia. Immunofixation showed polyclonal bands. Our patient was treated successfully with antibiotics, prednisone, and mycophenolate mofetil (MMF). This is the first report of a patient with partial DGS presenting with APS and type III mixed cryoglobulinemia possibly due to Streptococcal infection.

  17. Type III Mixed Cryoglobulinemia and Antiphospholipid Syndrome in a Patient With Partial DiGeorge Syndrome

    PubMed Central

    Chang, Alice D.; Tachdjian, Raffi; Gallagher, Kerry; McCurdy, Deborah K.; Lassman, Charles; Stiehm, E. Richard; Yadin, Ora

    2006-01-01

    We studied a 14 year-old boy with partial DiGeorge syndrome (DGS), status post complete repair of Tetralogy of Fallot, who developed antiphospholipid syndrome (APS) and type III mixed cryoglobulinemia. He presented with recurrent fever and dyspnea upon exertion secondary to right pulmonary embolus on chest computed tomography (CT). Coagulation studies revealed homozygous methylene tetrahydrofolate reductase 677TT mutations, elevated cardiolipin IgM antibodies, and elevated β2-glycoprotein I IgM antibodies. Infectious work-up revealed only positive anti-streptolysin O (ASO) and anti-DNAse B titers. Autoimmune studies showed strongly positive anti-platelet IgM, elevated rheumatoid factor (RF), and positive cryocrit. Renal biopsy for evaluation of proteinuria and hematuria showed diffuse proliferative glomerulonephritis (DPGN) with membranoproliferative features consistent with cryoglobulinemia. Immunofixation showed polyclonal bands. Our patient was treated successfully with antibiotics, prednisone, and mycophenolate mofetil (MMF). This is the first report of a patient with partial DGS presenting with APS and type III mixed cryoglobulinemia possibly due to Streptococcal infection. PMID:17162366

  18. Oleanolic Acid Induces the Type III Secretion System of Ralstonia solanacearum

    PubMed Central

    Wu, Dousheng; Ding, Wei; Zhang, Yong; Liu, Xuejiao; Yang, Liang

    2015-01-01

    Ralstonia solanacearum, the causal agent of bacterial wilt, can naturally infect a wide range of host plants. The type III secretion system (T3SS) is a major virulence determinant in this bacterium. Studies have shown that plant-derived compounds are able to inhibit or induce the T3SS in some plant pathogenic bacteria, though no specific T3SS inhibitor or inducer has yet been identified in R. solanacearum. In this study, a total of 50 different compounds were screened and almost half of them (22 of 50) significantly inhibited or induced the T3SS expression of R. solanacearum. Based on the strong induction activity on T3SS, the T3SS inducer oleanolic acid (OA) was chosen for further study. We found that OA induced the expression of T3SS through the HrpG-HrpB pathway. Some type III effector genes were induced in T3SS inducing medium supplemented with OA. In addition, OA targeted only the T3SS and did not affect other virulence determinants. Finally, we observed that induction of T3SS by OA accelerated disease progress on tobacco. Overall our results suggest that plant-derived compounds are an abundant source of R. solanacearum T3SS regulators, which could prove useful as tools to interrogate the regulation of this key virulence pathway. PMID:26732647

  19. The insect endosymbiont Sodalis glossinidius utilizes a type III secretion system for cell invasion

    PubMed Central

    Dale, Colin; Young, Simon A.; Haydon, Daniel T.; Welburn, Susan C.

    2001-01-01

    Sodalis glossinidius is a maternally transmitted secondary endosymbiont residing intracellularly in tissues of the tsetse flies, Glossina spp. In this study, we have used Tn5 mutagenesis and a negative selection procedure to derive a S. glossinidius mutant that is incapable of invading insect cells in vitro and is aposymbiotic when microinjected into tsetse. This mutant strain harbors Tn5 integrated into a chromosomal gene sharing high sequence identity with a type III secretion system invasion gene (invC) previously identified in Salmonella enterica. With the use of degenerate PCR, we have amplified a further six Sodalis inv/spa genes sharing high sequence identity with type III secretion system genes encoded by Salmonella pathogenicity island 1. Phylogenetic reconstructions based on the inv/spa genes of Sodalis and other members of the family Enterobacteriaceae have consistently identified a well-supported clade containing Sodalis and the enteric pathogens Shigella and Salmonella. These results suggest that Sodalis may have evolved from an ancestor with a parasitic intracellular lifestyle, possibly a latter-day entomopathogen. These observations lend credence to a hypothesis suggesting that vertically transmitted mutualistic endosymbionts evolve from horizontally transmitted parasites through a parasitism–mutualism continuum. PMID:11172045

  20. Methicillin-resistant Staphylococcus aureus sequence type 239-III, Ohio, USA, 2007-2009.

    PubMed

    Wang, Shu-Hua; Khan, Yosef; Hines, Lisa; Mediavilla, José R; Zhang, Liangfen; Chen, Liang; Hoet, Armando; Bannerman, Tammy; Pancholi, Preeti; Robinson, D Ashley; Kreiswirth, Barry N; Stevenson, Kurt B

    2012-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a human pathogen that has diverse molecular heterogeneity. Most MRSA strains in the United States are pulsed-field gel electrophoresis USA100 sequence type (ST) 5 and USA300 ST8. Infections with MRSA ST239-III are common and found during health care-associated outbreaks. However, this strain has been rarely reported in the United States. As part of a study supported by the Prevention Epicenter Program of the Centers for Disease Control and Prevention (Atlanta, GA, USA), which evaluated transmission of MRSA among hospitals in Ohio, molecular typing identified 78 (6%) of 1,286 patients with MRSA ST239-III infections. Ninety-five percent (74/78) of these infections were health care associated, and 65% (51/78) of patients had histories of invasive device use. The crude case-fatality rate was 22% (17/78). Identification of these strains, which belong to a virulent clonal group, emphasizes the need for molecular surveillance. PMID:23018025

  1. Type III Guyon Syndrome in 'B Boy' Break-Dancer: A Case Report

    PubMed Central

    Hu, Soo-young; Choi, Jin-gyu

    2015-01-01

    Although the musculoskeletal injuries associated with break-dancing which is gaining more popularity among adolescent and young people has been reported, the report regarding a peripheral nerve injury associated with breakdance is scarce. We report a rare case of a young amateur break-dancer, 'b-boy' who suffered from a painful paresthesia in his left hand, later diagnosed as type III Guyon's canal syndrome. A 23-year-old, right handed college man presented with a tenderness over the left hypothenar eminence and painful paresthesia over the ring and little fingers of 3 months duration. He trained himself as an amateur 'b boy' break-dancer for the last 10 months. Conservative management under the diagnosis of wrist sprain before presentation did not improve his hand pain. An magnetic resonance imaging and electrodiagnostic study revealed that painful paresthesia was caused by type III Guyon's canal syndrome, and 4 weeks of corticosteroid treatment was given with resolution of pain and paresthesia. PMID:27169091

  2. Mumps Virus Induces Protein-Kinase-R-Dependent Stress Granules, Partly Suppressing Type III Interferon Production

    PubMed Central

    Hashimoto, Shin; Yamamoto, Soh; Ogasawara, Noriko; Sato, Toyotaka; Yamamoto, Keisuke; Katoh, Hiroshi; Kubota, Toru; Shiraishi, Tsukasa; Kojima, Takashi; Himi, Tetsuo; Tsutsumi, Hiroyuki; Yokota, Shin-ichi

    2016-01-01

    Stress granules (SGs) are cytoplasmic granular aggregations that are induced by cellular stress, including viral infection. SGs have opposing antiviral and proviral roles, which depend on virus species. The exact function of SGs during viral infection is not fully understood. Here, we showed that mumps virus (MuV) induced SGs depending on activation of protein kinase R (PKR). MuV infection strongly induced interferon (IFN)-λ1, 2 and 3, and IFN-β through activation of IFN regulatory factor 3 (IRF3) via retinoic acid inducible gene-I (RIG-I) and the mitochondrial antiviral signaling (MAVS) pathway. MuV-induced IFNs were strongly upregulated in PKR-knockdown cells. MuV-induced SG formation was suppressed by knockdown of PKR and SG marker proteins, Ras-GTPase-activating protein SH3-domain-binding protein 1 and T-cell-restricted intracellular antigen-1, and significantly increased the levels of MuV-induced IFN-λ1. However, viral titer was not altered by suppression of SG formation. PKR was required for induction of SGs by MuV infection and regulated type III IFN (IFN-λ1) mRNA stability. MuV-induced SGs partly suppressed type III IFN production by MuV; however, the limited suppression was not sufficient to inhibit MuV replication in cell culture. Our results provide insight into the relationship between SGs and IFN production induced by MuV infection. PMID:27560627

  3. Methicillin-resistant Staphylococcus aureus sequence type 239-III, Ohio, USA, 2007-2009.

    PubMed

    Wang, Shu-Hua; Khan, Yosef; Hines, Lisa; Mediavilla, José R; Zhang, Liangfen; Chen, Liang; Hoet, Armando; Bannerman, Tammy; Pancholi, Preeti; Robinson, D Ashley; Kreiswirth, Barry N; Stevenson, Kurt B

    2012-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a human pathogen that has diverse molecular heterogeneity. Most MRSA strains in the United States are pulsed-field gel electrophoresis USA100 sequence type (ST) 5 and USA300 ST8. Infections with MRSA ST239-III are common and found during health care-associated outbreaks. However, this strain has been rarely reported in the United States. As part of a study supported by the Prevention Epicenter Program of the Centers for Disease Control and Prevention (Atlanta, GA, USA), which evaluated transmission of MRSA among hospitals in Ohio, molecular typing identified 78 (6%) of 1,286 patients with MRSA ST239-III infections. Ninety-five percent (74/78) of these infections were health care associated, and 65% (51/78) of patients had histories of invasive device use. The crude case-fatality rate was 22% (17/78). Identification of these strains, which belong to a virulent clonal group, emphasizes the need for molecular surveillance.

  4. Endofungal bacterium controls its host by an hrp type III secretion system.

    PubMed

    Lackner, Gerald; Moebius, Nadine; Hertweck, Christian

    2011-02-01

    Burkholderia rhizoxinica and Rhizopus microsporus form a unique symbiosis in which intracellular bacteria produce the virulence factor of the phytopathogenic fungus. Notably, the host strictly requires endobacteria to sporulate. In this study, we show that the endofungal bacteria possess a type III secretion system (T3SS), which has a crucial role in the maintenance of the alliance. Mutants defective in type III secretion show reduced intracellular survival and fail to elicit sporulation of the host. Furthermore, genes coding for T3SS components are upregulated during cocultivation of the bacterial symbiont with their host. This is the first report on a T3SS involved in bacterial-fungal symbiosis. Phylogenetic analysis revealed that the T3SS represents a prototype of a clade of yet uncharacterized T3SSs within the hrp superfamily of T3SSs from plant pathogenic microorganisms. In a control experiment, we demonstrate that under laboratory conditions, rhizoxin production was not required for establishment of the symbiotic interaction. PMID:20720578

  5. Type III Guyon Syndrome in 'B Boy' Break-Dancer: A Case Report.

    PubMed

    Hu, Soo-Young; Choi, Jin-Gyu; Son, Byung-Chul

    2015-10-01

    Although the musculoskeletal injuries associated with break-dancing which is gaining more popularity among adolescent and young people has been reported, the report regarding a peripheral nerve injury associated with breakdance is scarce. We report a rare case of a young amateur break-dancer, 'b-boy' who suffered from a painful paresthesia in his left hand, later diagnosed as type III Guyon's canal syndrome. A 23-year-old, right handed college man presented with a tenderness over the left hypothenar eminence and painful paresthesia over the ring and little fingers of 3 months duration. He trained himself as an amateur 'b boy' break-dancer for the last 10 months. Conservative management under the diagnosis of wrist sprain before presentation did not improve his hand pain. An magnetic resonance imaging and electrodiagnostic study revealed that painful paresthesia was caused by type III Guyon's canal syndrome, and 4 weeks of corticosteroid treatment was given with resolution of pain and paresthesia. PMID:27169091

  6. Satellite observations of type III solar radio bursts at low frequencies

    NASA Technical Reports Server (NTRS)

    Fainberg, J.; Stone, R. G.

    1974-01-01

    Type III solar radio bursts have been observed from 10 MHz to 10 kHz by satellite experiments above the terrestrial plasmasphere. Solar radio emission in this frequency range results from excitation of the interplanetary plasma by energetic particles propagating outward along open field lines over distances from 5 earth radii to at least 1 AU from the sun. This review summarizes the morphology, characteristics, and analysis of individual as well as storms of bursts. Substantial evidence is available to show that the radio emission is observed at the second harmonic instead of the fundamental of the plasma frequency. This brings the density scale derived by radio observations into better agreement with direct solar wind density measurements at 1 AU and relaxes the requirement for type III propagation along large density-enhanced regions. This density scale with the measured direction of arrival of the radio burst allows the trajectory of the exciter path to be determined from 10 earth radii to 1 AU.

  7. Visibility of Type III burst source location as inferred from stereoscopic space observations

    NASA Astrophysics Data System (ADS)

    Boudjada, M. Y.; Galopeau, P. H. M.; Maksimovic, M.; Rucker, H. O.

    2014-11-01

    We study solar Type III radio bursts simultaneously observed by RPWS/Cassini, URAP/Ulysses and WAVES/Wind experiments. The observations allows us to cover a large frequency bandwidth from 16MHz down to a few kHz. We consider the onset time of each burst, and estimate the corresponding intensity level. Also we measure the Langmuir frequency as observed on the dynamic spectra recorded by the Ulysses spacecraft. The distances of Wind, Ulysses and Cassini spacecraft, with regard to the Sun, were in the order of 1AU, 2.4AU and 4.5AU, respectively. The spacecraft trajectories were localized in the ecliptic plane in the case of Wind and Cassini, and for Ulysses in the southern hemisphere (i.e. heliocentric latitude higher than -50). Despite the different locations, the spectral patterns of the selected solar bursts are found to be similar between 10MHz and 2MHz but unalike at lower frequency. We discuss the variation of the intensity level as recorded by the three spacecraft. We show that the reception system of each experiment affected the way the Type III burst intensity is measured. Also we attempt to estimate the electron beam along the interplanetary magnetic field where the trajectory is an Archimedean spiral. This leads us to infer on the visibility of the source location with regard to the spacecraft position.

  8. Automatic Recognition of Type III Solar Radio Bursts in STEREO/WAVES Data

    NASA Astrophysics Data System (ADS)

    Lobzin, V. V.; Cairns, I. H.; Zaslavsky, A.

    2014-12-01

    Type III radio bursts are produced near the local electron plasma frequency and/or near its harmonic by fast electrons ejected from the solar active regions and moving through the corona and solar wind. These bursts have dynamic spectra with frequency rapidly falling with time. This paper presents two new methods developed to detect type III bursts automatically in the data from High Frequency Receiver (HFR) of the STEREO/WAVES radio instrument onboard the STEREO spacecraft. The first technique is applicable to the low-frequency band (HFR-1: 125 kHz to 1.975 MHz) only. This technique can possibly be implemented in onboard satellite software aimed at preliminary detection of bursts and identification of time intervals with relatively high solar activity. In the second technique the bursts are detected in both the low-frequency band and the high-frequency band (HFR-2: 2.025 MHz to 16.025 MHz), with the computational burden being higher by 1 order of magnitude as compared with that for the first technique. Preliminary tests of the method show that for the first technique the pobability to detect is quite high, Pd L = 72% ± 3%. The performance of the second technique is considerably higher, Pd L+H = 81%±1%, while the number of false alarms does not exceed 10% for one daily spectrum.

  9. Pore-forming Activity of the Escherichia coli Type III Secretion System Protein EspD.

    PubMed

    Chatterjee, Abhishek; Caballero-Franco, Celia; Bakker, Dannika; Totten, Stephanie; Jardim, Armando

    2015-10-16

    Enterohemorrhagic Escherichia coli is a causative agent of gastrointestinal and diarrheal diseases. Pathogenesis associated with enterohemorrhagic E. coli involves direct delivery of virulence factors from the bacteria into epithelial cell cytosol via a syringe-like organelle known as the type III secretion system. The type III secretion system protein EspD is a critical factor required for formation of a translocation pore on the host cell membrane. Here, we show that recombinant EspD spontaneously integrates into large unilamellar vesicle (LUV) lipid bilayers; however, pore formation required incorporation of anionic phospholipids such as phosphatidylserine and an acidic pH. Leakage assays performed with fluorescent dextrans confirmed that EspD formed a structure with an inner diameter of ∼2.5 nm. Protease mapping indicated that the two transmembrane helical hairpin of EspD penetrated the lipid layer positioning the N- and C-terminal domains on the extralumenal surface of LUVs. Finally, a combination of glutaraldehyde cross-linking and rate zonal centrifugation suggested that EspD in LUV membranes forms an ∼280-320-kDa oligomeric structure consisting of ∼6-7 subunits.

  10. Unusual xanthomas in a young patient with heterozygous familial hypercholesterolemia and type III hyperlipoproteinemia

    SciTech Connect

    Feussner, G.; Dobmeyer, J.; Nissen, H.; Hansen, T.S.

    1996-10-16

    We report on a 20-year-old man with the combination of two independent familial lipoprotein disorders: heterozygous familial hypercholesterolemia (FH) and type III hyperlipoproteinemia (HLP). Familial hypercholesterolemia was diagnosed by elevated total and low density lipoprotein cholesterol levels and family history. By denaturing gradient gel electrophoresis, DNA sequencing and restriction fragment length polymorphism analysis, a G{r_arrow}A splice donor mutation in intron 3 of the proband`s low density lipoprotein receptor gene was identified as the underlying molecular defect. This mutation was described previously as a receptor-negative founder mutation in Norway (FH-Elverum) and subsequently in 6 unrelated heterozygous English patients, creating a severe phenotype of familial hypercholesterolemia. Type III HLP was confirmed by homozygosity for apolipoprotein (apo) E2 and an elevated ratio of very low density lipoprotein cholesterol to serum triglycerides (0.40; normal ratio about 0.20). The patient has unusual flat xanthomas in the interdigital webs of the hands which are normally not found in either disease. These dermatological findings might therefore be indicative of the rare combination of both disorders of lipoprotein metabolism in one individual. 29 refs., 5 figs., 1 tab.

  11. Spinal muscular atrophy type III: Molecular genetic characterization of Turkish patients.

    PubMed

    Bora-Tatar, Gamze; Yesbek-Kaymaz, Ayse; Bekircan-Kurt, Can Ebru; Erdem-Özdamar, Sevim; Erdem-Yurter, Hayat

    2015-12-01

    Spinal Muscular Atrophy (SMA) is a neurodegenerative disease with autosomal recessive inheritance. Homozygous loss of exon 7 of the Survival of motor neuron 1 (SMN1) gene is the main cause of SMA. Although progressive muscle weakness and atrophy are common symptoms, disease severity varies from severe to mild. Type III is one of the milder and less frequent forms of SMA. In this study, we report molecular genetic characteristics of 24 Turkish type III SMA patients. Homozygous loss of SMN1 exon 7 and 8 was analysed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and multiplex ligation dependent probe amplification (MLPA). SMN2, homologue of SMN1, and Neuronal apoptosis inhibitory protein (NAIP) genes were also evaluated considering their influence on disease severity. We determined that male patients who were born in consanguineous families were predominant in our cohort and these patients mostly carry the homozygous loss of SMN1 exon 7 and 8 and four copies of SMN2 gene without NAIP deletions. PMID:26548498

  12. Global impact of Salmonella type III secretion effector SteA on host cells.

    PubMed

    Cardenal-Muñoz, Elena; Gutiérrez, Gabriel; Ramos-Morales, Francisco

    2014-07-11

    Salmonella enterica is a Gram-negative bacterium that causes gastroenteritis, bacteremia and typhoid fever in several animal species including humans. Its virulence is greatly dependent on two type III secretion systems, encoded in pathogenicity islands 1 and 2. These systems translocate proteins called effectors into eukaryotic host cell. Effectors interfere with host signal transduction pathways to allow the internalization of pathogens and their survival and proliferation inside vacuoles. SteA is one of the few Salmonella effectors that are substrates of both type III secretion systems. Here, we used gene arrays and bioinformatics analysis to study the genetic response of human epithelial cells to SteA. We found that constitutive synthesis of SteA in HeLa cells leads to induction of genes related to extracellular matrix organization and regulation of cell proliferation and serine/threonine kinase signaling pathways. SteA also causes repression of genes related to immune processes and regulation of purine nucleotide synthesis and pathway-restricted SMAD protein phosphorylation. In addition, a cell biology approach revealed that epithelial cells expressing steA show altered cell morphology, and decreased cytotoxicity, cell-cell adhesion and migration.

  13. A Repulsive Electrostatic Mechanism for Protein Export through the Type III Secretion Apparatus

    PubMed Central

    Rathinavelan, Thenmalarchelvi; Zhang, Lingling; Picking, Wendy L.; Weis, David D.; De Guzman, Roberto N.; Im, Wonpil

    2010-01-01

    Abstract Many Gram-negative bacteria initiate infections by injecting effector proteins into host cells through the type III secretion apparatus, which is comprised of a basal body, a needle, and a tip. The needle channel is formed by the assembly of a single needle protein. To explore the export mechanisms of MxiH needle protein through the needle of Shigella flexneri, an essential step during needle assembly, we have performed steered molecular dynamics simulations in implicit solvent. The trajectories reveal a screwlike rotation motion during the export of nativelike helix-turn-helix conformations. Interestingly, the channel interior with excessive electronegative potential creates an energy barrier for MxiH to enter the channel, whereas the same may facilitate the ejection of the effectors into host cells. Structurally known basal regions and ATPase underneath the basal region also have electronegative interiors. Effector proteins also have considerable electronegative potential patches on their surfaces. From these observations, we propose a repulsive electrostatic mechanism for protein translocation through the type III secretion apparatus. Based on this mechanism, the ATPase activity and/or proton motive force could be used to energize the protein translocation through these nanomachines. A similar mechanism may be applicable to macromolecular channels in other secretion systems or viruses through which proteins or nucleic acids are transported. PMID:20141759

  14. Mumps Virus Induces Protein-Kinase-R-Dependent Stress Granules, Partly Suppressing Type III Interferon Production.

    PubMed

    Hashimoto, Shin; Yamamoto, Soh; Ogasawara, Noriko; Sato, Toyotaka; Yamamoto, Keisuke; Katoh, Hiroshi; Kubota, Toru; Shiraishi, Tsukasa; Kojima, Takashi; Himi, Tetsuo; Tsutsumi, Hiroyuki; Yokota, Shin-Ichi

    2016-01-01

    Stress granules (SGs) are cytoplasmic granular aggregations that are induced by cellular stress, including viral infection. SGs have opposing antiviral and proviral roles, which depend on virus species. The exact function of SGs during viral infection is not fully understood. Here, we showed that mumps virus (MuV) induced SGs depending on activation of protein kinase R (PKR). MuV infection strongly induced interferon (IFN)-λ1, 2 and 3, and IFN-β through activation of IFN regulatory factor 3 (IRF3) via retinoic acid inducible gene-I (RIG-I) and the mitochondrial antiviral signaling (MAVS) pathway. MuV-induced IFNs were strongly upregulated in PKR-knockdown cells. MuV-induced SG formation was suppressed by knockdown of PKR and SG marker proteins, Ras-GTPase-activating protein SH3-domain-binding protein 1 and T-cell-restricted intracellular antigen-1, and significantly increased the levels of MuV-induced IFN-λ1. However, viral titer was not altered by suppression of SG formation. PKR was required for induction of SGs by MuV infection and regulated type III IFN (IFN-λ1) mRNA stability. MuV-induced SGs partly suppressed type III IFN production by MuV; however, the limited suppression was not sufficient to inhibit MuV replication in cell culture. Our results provide insight into the relationship between SGs and IFN production induced by MuV infection. PMID:27560627

  15. Type III secretion: a secretory pathway serving both motility and virulence (review).

    PubMed

    Journet, Laure; Hughes, Kelly T; Cornelis, Guy R

    2005-01-01

    'Type III secretion' (T3S) refers to a secretion pathway that is common to the flagellae of eubacteria and the injectisomes of some gram-negative bacteria. Flagellae are rotary nanomachines allowing motility but they contain a built-in secretion apparatus that exports their own distal components to the distal end of the growing structure where they polymerize. In some cases they have been shown to export non-flagellar proteins. Injectisomes are transkingdom communication apparatuses allowing bacteria docked at the surface of a eukaryotic cell membrane to inject effector proteins across the two bacterial membranes and the eukaryotic cell membrane. Both nanomachines share a similar basal body embedded in the two bacterial membranes, topped either by a hook and a filament or by a stiff short needle. Both appear to be assembled in the same fashion. They recognize their substrate by a loose N-terminal peptide signal and the help of individual chaperones of a new type. PMID:16092523

  16. Development of Two Animal Models To Study the Function of Vibrio parahaemolyticus Type III Secretion Systems▿

    PubMed Central

    Piñeyro, Pablo; Zhou, Xiaohui; Orfe, Lisa H.; Friel, Patrick J.; Lahmers, Kevin; Call, Douglas R.

    2010-01-01

    Vibrio parahaemolyticus is an emerging food- and waterborne pathogen that encodes two type III secretion systems (T3SSs). Previous studies have linked type III secretion system 1 (T3SS1) to cytotoxicity and T3SS2 to intestinal fluid accumulation, but animal challenge models needed to study these phenomena are limited. In this study we evaluated the roles of the T3SSs during infection using two novel animal models: a model in which piglets were inoculated orogastrically and a model in which mice were inoculated in their lungs (intrapulmonarily). The bacterial strains employed in this study had equivalent growth rates and beta-hemolytic activity based on in vitro assays. Inoculation of 48-h-old conventional piglets with 1011 CFU of the wild-type strain (NY-4) or T3SS1 deletion mutant strains resulted in acute, self-limiting diarrhea, whereas inoculation with a T3SS2 deletion mutant strain failed to produce any clinical symptoms. Intrapulmonary inoculation of C57BL/6 mice with the wild-type strain and T3SS2 deletion mutant strains (5 × 105 CFU) induced mortality or a moribund state within 12 h (80 to 100% mortality), whereas inoculation with a T3SS1 deletion mutant or a T3SS1 T3SS2 double deletion mutant produced no mortality. Bacteria were recovered from multiple organs regardless of the strain used in the mouse model, indicating that the mice were capable of clearing the lung infection in the absence of a functional T3SS1. Because all strains had a similar beta-hemolysin phenotype, we surmise that thermostable direct hemolysin (TDH) plays a limited role in these models. The two models introduced herein produce robust results and provide a means to determine how different T3SS1 and T3SS2 effector proteins contribute to pathogenesis of V. parahaemolyticus infection. PMID:20823199

  17. Subtypes of Batterers in Treatment: Empirical Support for a Distinction between Type I, Type II and Type III

    PubMed Central

    Graña, José Luis; Redondo, Natalia; Muñoz-Rivas, Marina J.; Cantos, Arthur L.

    2014-01-01

    This study explores the existence of different types of batterers in a sample of 266 men who had been court referred for intimate partner violence. The data collected in the assessment that have been used to perform a hierarchical and a two-step cluster analysis fall into three areas: aggression towards the partner, general aggression and presence of psychopathology and personality traits, more specifically, alcohol use, borderline and antisocial personality traits, psychopathy traits, state anger and trait anger, anger expression and control, anger, hostility, and, finally, impulsivity. The results show a typology consisting of 3 types of batterers on the basis of violence level and psychopathology: low (65%), moderate (27.8%) and high (7.1%). This study provides empirical support for the development of batterer typologies. These typologies will help achieve early detection of different types of batterers, allowing us to tailor interventions on the basis of the needs of each of the types. PMID:25329828

  18. Type- and Subcomplex-Specific Neutralizing Antibodies against Domain III of Dengue Virus Type 2 Envelope Protein Recognize Adjacent Epitopes▿

    PubMed Central

    Sukupolvi-Petty, Soila; Austin, S. Kyle; Purtha, Whitney E.; Oliphant, Theodore; Nybakken, Grant E.; Schlesinger, Jacob J.; Roehrig, John T.; Gromowski, Gregory D.; Barrett, Alan D.; Fremont, Daved H.; Diamond, Michael S.

    2007-01-01

    Neutralization of flaviviruses in vivo correlates with the development of an antibody response against the viral envelope (E) protein. Previous studies demonstrated that monoclonal antibodies (MAbs) against an epitope on the lateral ridge of domain III (DIII) of the West Nile virus (WNV) E protein strongly protect against infection in animals. Based on X-ray crystallography and sequence analysis, an analogous type-specific neutralizing epitope for individual serotypes of the related flavivirus dengue virus (DENV) was hypothesized. Using yeast surface display of DIII variants, we defined contact residues of a panel of type-specific, subcomplex-specific, and cross-reactive MAbs that recognize DIII of DENV type 2 (DENV-2) and have different neutralizing potentials. Type-specific MAbs with neutralizing activity against DENV-2 localized to a sequence-unique epitope on the lateral ridge of DIII, centered at the FG loop near residues E383 and P384, analogous in position to that observed with WNV-specific strongly neutralizing MAbs. Subcomplex-specific MAbs that bound some but not all DENV serotypes and neutralized DENV-2 infection recognized an adjacent epitope centered on the connecting A strand of DIII at residues K305, K307, and K310. In contrast, several MAbs that had poor neutralizing activity against DENV-2 and cross-reacted with all DENV serotypes and other flaviviruses recognized an epitope with residues in the AB loop of DIII, a conserved region that is predicted to have limited accessibility on the mature virion. Overall, our experiments define adjacent and structurally distinct epitopes on DIII of DENV-2 which elicit type-specific, subcomplex-specific, and cross-reactive antibodies with different neutralizing potentials. PMID:17881453

  19. Type- and subcomplex-specific neutralizing antibodies against domain III of dengue virus type 2 envelope protein recognize adjacent epitopes.

    PubMed

    Sukupolvi-Petty, Soila; Austin, S Kyle; Purtha, Whitney E; Oliphant, Theodore; Nybakken, Grant E; Schlesinger, Jacob J; Roehrig, John T; Gromowski, Gregory D; Barrett, Alan D; Fremont, Daved H; Diamond, Michael S

    2007-12-01

    Neutralization of flaviviruses in vivo correlates with the development of an antibody response against the viral envelope (E) protein. Previous studies demonstrated that monoclonal antibodies (MAbs) against an epitope on the lateral ridge of domain III (DIII) of the West Nile virus (WNV) E protein strongly protect against infection in animals. Based on X-ray crystallography and sequence analysis, an analogous type-specific neutralizing epitope for individual serotypes of the related flavivirus dengue virus (DENV) was hypothesized. Using yeast surface display of DIII variants, we defined contact residues of a panel of type-specific, subcomplex-specific, and cross-reactive MAbs that recognize DIII of DENV type 2 (DENV-2) and have different neutralizing potentials. Type-specific MAbs with neutralizing activity against DENV-2 localized to a sequence-unique epitope on the lateral ridge of DIII, centered at the FG loop near residues E383 and P384, analogous in position to that observed with WNV-specific strongly neutralizing MAbs. Subcomplex-specific MAbs that bound some but not all DENV serotypes and neutralized DENV-2 infection recognized an adjacent epitope centered on the connecting A strand of DIII at residues K305, K307, and K310. In contrast, several MAbs that had poor neutralizing activity against DENV-2 and cross-reacted with all DENV serotypes and other flaviviruses recognized an epitope with residues in the AB loop of DIII, a conserved region that is predicted to have limited accessibility on the mature virion. Overall, our experiments define adjacent and structurally distinct epitopes on DIII of DENV-2 which elicit type-specific, subcomplex-specific, and cross-reactive antibodies with different neutralizing potentials.

  20. STRUCTURE OF THE TYPE III PANTOTHENATE KINASE FROM Bacillus anthracis AT 2.0 Å RESOLUTION

    PubMed Central

    Nicely, Nathan I.; Parsonage, Derek; Paige, Carleitta; Newton, Gerald L.; Fahey, Robert C.; Leonardi, Roberta; Jackowski, Suzanne; Mallett, T. Conn; Claiborne, Al

    2008-01-01

    Coenzyme A (CoASH) is the major low-molecular weight thiol in Staphylococcus aureus and a number of other bacteria; the crystal structure of the S. aureus coenzyme A-disulfide reductase (CoADR), which maintains the reduced intracellular state of CoASH, has recently been reported [Mallett, T.C., Wallen, J.R., Karplus, P.A., Sakai, H., Tsukihara, T., and Claiborne, A. (2006) Biochemistry 45, 11278-11289]. In this report we demonstrate that CoASH is the major thiol in Bacillus anthracis; a bioinformatics analysis indicates that three of the four proteins responsible for the conversion of pantothenate (Pan) to CoASH in Escherichia coli are conserved in B. anthracis. In contrast, a novel type III pantothenate kinase (PanK) catalyzes the first committed step in the biosynthetic pathway in B. anthracis; unlike the E. coli type I PanK, this enzyme is not subject to feedback inhibition by CoASH. The crystal structure of B. anthracis PanK (BaPanK), solved using multiwavelength anomalous dispersion data and refined at a resolution of 2.0 Å, demonstrates that BaPanK is a new member of the Acetate and Sugar Kinase/Hsc70/Actin (ASKHA) superfamily. The Pan and ATP substrates have been modeled into the active-site cleft; in addition to providing a clear rationale for the absence of CoASH inhibition, analysis of the Pan-binding pocket has led to the development of two new structure-based motifs (the PAN and INTERFACE motifs). Our analyses also suggest that the type III PanK in the spore-forming B. anthracis plays an essential role in the novel thiol/disulfide redox biology of this category A biodefense pathogen. PMID:17323930

  1. Discovery and characterization of inhibitors of Pseudomonas aeruginosa type III secretion.

    PubMed

    Aiello, Daniel; Williams, John D; Majgier-Baranowska, Helena; Patel, Ishan; Peet, Norton P; Huang, Jin; Lory, Stephen; Bowlin, Terry L; Moir, Donald T

    2010-05-01

    The type III secretion system (T3SS) is a clinically important virulence mechanism in Pseudomonas aeruginosa that secretes and translocates up to four protein toxin effectors into human cells, facilitating the establishment and dissemination of infections. To discover inhibitors of this important virulence mechanism, we developed two cellular reporter assays and applied them to a library of 80,000 compounds. The primary screen was based on the dependence of the transcription of T3SS operons on the T3SS-mediated secretion of a negative regulator and consisted of a transcriptional fusion of the Photorhabdus luminescens luxCDABE operon to the P. aeruginosa exoT effector gene. Secondary assays included direct measurements of the T3SS-mediated secretion of a P. aeruginosa ExoS effector-beta-lactamase fusion protein as well as the detection of the secretion of native ExoS by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of culture supernatants. Five inhibitors in three chemical classes were demonstrated to inhibit type III secretion selectively with minimal cytotoxicity and with no effects on bacterial growth or on the type II-mediated secretion of elastase. These inhibitors also block the T3SS-mediated secretion of a YopE effector-beta-lactamase fusion protein from an attenuated Yersinia pestis strain. The most promising of the inhibitors is a phenoxyacetamide that also blocks the T3SS-mediated translocation of effectors into mammalian cells in culture. Preliminary studies of structure-activity relationships in this phenoxyacetamide series demonstrated a strict requirement for the R-enantiomer at its stereocenter and indicated tolerance for a variety of substituents on one of its two aromatic rings. PMID:20176902

  2. Analysis of Cells Targeted by Salmonella Type III Secretion In Vivo

    PubMed Central

    Geddes, Kaoru; Cruz, Frank; Heffron, Fred

    2007-01-01

    The type III secretion systems (TTSS) encoded in Salmonella pathogenicity island-1 and -2 (SPI-1 and -2) are virulence factors required for specific phases of Salmonella infection in animal hosts. However, the host cell types targeted by the TTSS have not been determined. To investigate this, we have constructed translational fusions between the ß-lactamase reporter and a broad array of TTSS effectors secreted via SPI-1, SPI-2, or both. Secretion of the fusion protein to a host cell was determined by cleavage of a specific fluorescent substrate. In cultured cells, secretion of all six effectors could be observed. However, two to four days following i.p. infection of mice, only effectors secreted by SPI-2 were detected in spleen cells. The cells targeted were identified via staining with nine different cell surface markers followed by FACS analysis as well as by conventional cytological methods. The targeted cells include B and T lymphocytes, neutrophils, monocytes, and dendritic cells, but not mature macrophages. To further investigate replication in these various cell types, Salmonella derivatives were constructed that express a red fluorescent protein. Bacteria could be seen in each of the cell types above; however, most viable bacteria were present in neutrophils. We find that Salmonella is capable of targeting most phagocytic and non-phagocytic cells in the spleen but has a surprisingly high preference for neutrophils. These findings suggest that Salmonella specifically target splenic neutrophils presumably to attenuate their microbicidal functions, thereby promoting intracellular survival and replication in the mouse. PMID:18159943

  3. Induction of dendritic cell production of type I and type III interferons by wild-type and vaccine strains of measles virus: role of defective interfering RNAs.

    PubMed

    Shivakoti, Rupak; Siwek, Martina; Hauer, Debra; Schultz, Kimberly L W; Griffin, Diane E

    2013-07-01

    The innate immune response to viral infection frequently includes induction of type I interferons (IFN), but many viruses have evolved ways to block this response and increase virulence. In vitro studies of IFN production after infection of susceptible cells with measles virus (MeV) have often reported greater IFN synthesis after infection with vaccine than with wild-type strains of MeV. However, the possible presence in laboratory virus stocks of 5' copy-back defective interfering (DI) RNAs that induce IFN independent of the standard virus has frequently confounded interpretation of data from these studies. To further investigate MeV strain-dependent differences in IFN induction and the role of DI RNAs, monocyte-derived dendritic cells (moDCs) were infected with the wild-type Bilthoven strain and the vaccine Edmonston-Zagreb strain with and without DI RNAs. Production of type I IFN, type III IFN, and the interferon-stimulated genes (ISGs) Mx and ISG56 by infected cells was assessed with a flow cytometry-based IFN bioassay, quantitative reverse transcriptase PCR (RT-PCR), and immunoassays. Bilthoven infected moDCs less efficiently than Edmonston-Zagreb. Presence of DI RNAs in vaccine stocks resulted in greater maturation of moDCs, inhibition of virus replication, and induction of higher levels of IFN and ISGs. Production of type I IFN, type III IFN, and ISG mRNA and protein was determined by both the level of infection and the presence of DI RNAs. At the same levels of infection and in the absence of DI RNA, IFN induction was similar between wild-type and vaccine strains of MeV. PMID:23678166

  4. EVIDENCE FOR GENTLY SLOPING PLASMA DENSITY PROFILES IN THE DEEP CORONA: TYPE III OBSERVATIONS

    SciTech Connect

    Lobzin, V. V.; Cairns, I. H.; Robinson, P. A.; Warmuth, A.; Mann, G.; Gorgutsa, R. V.; Fomichev, V. V.

    2010-12-01

    Type III radio bursts are produced near the local electron plasma frequency f{sub p} and near its harmonic 2f{sub p} by fast electrons ejected from the solar active regions and moving through the corona and solar wind. The coronal bursts have dynamic spectra with frequency rapidly falling with time, the typical duration being about 1-3 s. In the present paper, 37 well-defined coronal type III radio bursts (25-450 MHz) are analyzed. The results obtained substantiate an earlier statement that the dependence of the central frequency of the emission on time can be fitted to a power-law model, f(t) {proportional_to} (t - t{sub 0}){sup -{alpha}}, where {alpha} can be as low as 1. In the case of negligible plasma acceleration and conical flow, it means that the electron number density within about 1 solar radius above the photosphere will decrease as r {sup -2}, like in the solar wind. For the data set chosen, the index {alpha} varies in the range from 0.2 to 7 or bigger, with mean and median values of 1.2 and 0.5, respectively. A surprisingly large fraction of events, 84%, have {alpha} {<=} 1.2. These results provide strong evidence that in the type III source regions the electron number density scales as n(r) {proportional_to} (r - r{sub 0}){sup -{beta}}, with minimum, mean, and median {beta} = 2{alpha} of 0.4, 2.4, and 1.0, respectively. Hence, the typical density profiles are more gently sloping than those given by existing empirical coronal models. Several events are found with a wind-like dependence of burst frequency on time. Smaller power-law indices could result from the effects of non-conical geometry of the plasma flow tubes, deceleration of coronal plasma, and/or the curvature of the magnetic field lines. The last effect is shown to be too weak to explain such low power-law indices. A strong tendency is found for bursts from the same group to have similar power-law indices, thereby favoring the hypothesis that they are usually produced by the same source

  5. Comparison of the clinicopathological characteristics and the survival outcomes between the Siewert type II/III adenocarcinomas.

    PubMed

    Zhang, Wei-Han; Chen, Xin-Zu; Liu, Kai; Anil, Kumar; Yang, Kun; Chen, Jia-Ping; Zhou, Zong-Guang; Hu, Jian-Kun

    2014-08-01

    The aim of the study was to analyze the clinicopathological characteristics and survival outcomes in Siewert type II and Siewert type III tumors. The clinicopathological characteristics and survival outcomes were analyzed in patients diagnosed with Siewert II/III tumors, who underwent transabdominal gastrectomy from Jan 2006 to Dec 2010. A total of 321 patients diagnosed with Siewert II/III tumors who underwent gastrectomy were enrolled in this study. Siewert III tumors are larger and have a higher proportion of Borrmann 3-4 types than Siewert II tumors (p < 0.05). For Siewert II and the Siewert III tumors, the 3-year overall survival rate was 59.1 versus 57.1 %, respectively, and the median survival time was 46.0 (31.5-60.5) months versus 46.0 (31.3-60.7) months, respectively. Positive proximal resection margin, large tumor size, Borrmann 3-4 types, poor or undifferentiated degree and advanced T stages and N stages were found to be poor prognostic risk factors for the overall survival outcomes by univariate analysis. Multivariate analysis revealed that the differentiation degree (poor and undifferentiated) and advanced T and N stages were independent prognostic factors for poor overall survival. Siewert III tumors were larger and had a lower differentiation degree than Siewert II tumors, whereas there was no difference in the survival outcomes.

  6. {nu}-gauge mediated supersymmetry breaking with type III seesaw mechanism and phenomenology

    SciTech Connect

    Mohapatra, R. N.; Okada, Nobuchika; Yu Haibo

    2008-10-01

    We show that when the supersymmetric SU(5) model is extended to explain small neutrino masses by the type III seesaw mechanism, the new 24-dimensional fields needed for the purpose can act as messengers for transmitting SUSY breaking from a hidden sector to the visible sector. For the three 24s case, the constraints of grand unification and suppressed lepton flavor violation restrict the seesaw scale in this case to be in the narrow range of 10{sup 12}-10{sup 13} GeV. The model predicts (i) a stable lightest superpartner gravitino with mass in the range of 1-10 MeV which can be a cold dark matter of the universe; (ii) a stau next to lightest superpartner, which is detectable at the LHC; (iii) a lower bound on the branching ratio BR({mu}{yields}e{gamma}) larger than 10{sup -14} testable by the ongoing Muegamma (MEG) experiment as well as a characteristic particle spectrum different from other SUSY breaking scenarios. We also discuss the case with two 24 fields, which is the minimal case that can explain neutrino oscillation data.

  7. Limited In Vivo Production of Type I or Type III Interferon After Infection of Macaques with Vaccine or Wild-Type Strains of Measles Virus

    PubMed Central

    Shivakoti, Rupak; Hauer, Debra; Adams, Robert J.; Lin, Wen-Hsuan W.; Duprex, William Paul; de Swart, Rik L.

    2015-01-01

    The innate immune response to viral infections often includes induction of types I and III interferons (IFNs) and production of antiviral proteins. Measles is a severe virus-induced rash disease, but in vitro studies suggest that in the absence of defective interfering RNAs, neither wild-type (WT) nor vaccine strains of measles virus (MeV) induce IFN. To determine whether IFN is produced in vivo, we studied tissues from macaques infected with vaccine or WT strains of MeV using quantitative reverse transcriptase–polymerase chain reaction to assess levels of IFN and IFN-stimulated gene (ISG) mRNAs and a flow cytometry-based bioassay to assess levels of biologically active IFN. There was little to no induction of type I IFN, type III IFN, Mx, or ISG56 mRNAs in monkeys infected with vaccine or WT MeV and no IFN detection by bioassay. Therefore, the innate responses to infection with vaccine or WT strains of MeV are not dependent on IFN production. PMID:25517681

  8. The effects of NSAIDs on types I, II, and III collagen metabolism in a rat osteoarthritis model.

    PubMed

    Ou, Yun-Sheng; Tan, Chao; An, Hong; Jiang, Dian-Ming; Quan, Zheng-Xue; Tang, Ke; Luo, Xiao-Ji

    2012-08-01

    The effects of long-term use of celecoxib, ibuprofen, and indomethacin on types I, II, and III collagen metabolism were evaluated in rat osteoarthritis (OA) model. One hundred and thirty wistar rats were randomly divided into 4 groups: the celecoxib group, the ibuprofen group, the indomethacin group, and the normal saline group. The osteoarthritis was induced by the excision of the left Achilles tendon. In the 3rd, 6th, and 9th month of treatment after surgically induced osteoarthritis, the articular cartilage was observed with microscope using HE staining. The expression of proteoglycans was semiquantified using toluidine blue staining. And, the expressions of types I, II, and III collagen in chondrocytes were examined using immunohistochemistry. The results suggested that celecoxib had no remarkable effects on the expression of types I, II, and III collagen. Ibuprofen upgraded the expression of types I, II, and III collagen and increased the synthesis of collagen. Indomethacin suppressed the expression of type II collagen and enhanced the expression of types I and III collagen. Therefore, during the long-term use of NSAIDs in osteoarthritis, celecoxib may have no remarkable influences on collagen metabolism of the articular cartilage and may be the ideal choice in the treatment of chronic destructive joint disease when anti-inflammatory drugs need to be used for a prolonged period. Ibuprofen may be unfavorable, and indomethacin may be harmful to collagen metabolism in OA treatment.

  9. Statistical study of the correlation of hard X-ray and type III radio bursts in solar flares

    NASA Technical Reports Server (NTRS)

    Hamilton, Russell J.; Petrosian, Vahe; Benz, A. O.

    1990-01-01

    A large number of hard X-ray events which occurred during the maximum of solar cycle 21 have been analyzed in order to study their correlation with type III bursts. It is found that the distribution of occurrences of hard X-ray bursts correlated with type III radio bursts is significantly different from the distribution of all hard X-ray bursts. This result is consistent with the assumption that the hard X-ray and type III intensities are somewhat correlated. A bivariate distribution function of the burst intensities is fitted to the data and is used to determine that the typical ratio of X-ray intensity to type II intensity is about 10 and that the ratio of the number of X-ray producing-electrons to type III-producing electrons is about 1000. Three models which have been proposed to explain the relation between the accelerated hard X-ray and type III-producing electrons are examined in the context of these observations.

  10. Statistical study of the correlation of hard X-ray and type III radio bursts in solar flares

    SciTech Connect

    Hamilton, R.J.; Petrosian, V.; Benz, A.O. Zuerich Eidgenoessische Technische Hochschule )

    1990-08-01

    A large number of hard X-ray events which occurred during the maximum of solar cycle 21 have been analyzed in order to study their correlation with type III bursts. It is found that the distribution of occurrences of hard X-ray bursts correlated with type III radio bursts is significantly different from the distribution of all hard X-ray bursts. This result is consistent with the assumption that the hard X-ray and type III intensities are somewhat correlated. A bivariate distribution function of the burst intensities is fitted to the data and is used to determine that the typical ratio of X-ray intensity to type II intensity is about 10 and that the ratio of the number of X-ray producing-electrons to type III-producing electrons is about 1000. Three models which have been proposed to explain the relation between the accelerated hard X-ray and type III-producing electrons are examined in the context of these observations. 17 refs.

  11. Effects of Spatial Variations in Coronal Electron and Ion Temperatures on Type III Bursts. II. Variations in Ion Temperature

    NASA Astrophysics Data System (ADS)

    Li, B.; Cairns, Iver H.; Robinson, P. A.

    2011-03-01

    Quasilinear-based simulations are presented for the effects on coronal type III bursts of spatially varying ion temperature Ti in the corona. The simulations use a newly developed method for integrating spatial variations of coronal temperatures into our previous simulations for constant temperatures. The effects are simulated for monotonic Ti variations and/or for spatially localized enhancements in Ti . Generally, a localized enhancement in Ti has stronger effects on type III bursts than a corresponding monotonic variation in Ti . A localized Ti enhancement causes modulations to the dynamic spectra of fp and 2fp emission at frequencies corresponding to the disturbance: a narrowband slowly drifting intensification for both fp and 2fp emission and a narrowband suppression for 2fp emission. The fp emission may become observable due to the disturbance, although still much weaker than the 2fp emission. Signatures of the Ti enhancement are found in the 2fp spectral characteristics, e.g., the maximum flux and frequency drift rate. Importantly, these signatures are distinct from those of localized disturbances in electron temperature Te . The results indicate that coronal type III bursts provide a new tool to probe and distinguish localized disturbances in Ti or Te in the corona. Additionally, the presence of multiple spatially confined Ti enhancements at different heights may produce some observed fine structures in type III bursts; e.g., stria bursts and associated flux modulations in type IIIb bursts, and flux modulations in type IIIs whose beams traverse coronal shocks.

  12. Type I, II, and III Interferons: Regulating Immunity to Mycobacterium tuberculosis Infection.

    PubMed

    Travar, Maja; Petkovic, Miroslav; Verhaz, Antonija

    2016-02-01

    Interferons (IFNs) are cytokines released by host cells in response to the presence of pathogens or tumor cells. The aim of this review was to present the previously known and new findings about the role of interferons type I and II, and recently discovered type III in Mycobacterium tuberculosis (M. tuberculosis) infection control. Infection of various cell types with M. tuberculosis induce both IFN-α and IFN-β synthesis. The majority of the studies support the findings that IFN type I actually promotes infection with M. tuberculosis. It has been well establish that IFN-γ has protective function against M. tuberculosis and the other mycobacteria and that the primary source of this cytokine are CD4(+) and CD8(+) T cells. Recently, it has been shown that also the innate lymphocytes, γδ T cells, natural killer (NK) T cells, and NK cells can also be the source of IFN-γ in response to mycobacterial infection. Several studies have shown that CD4(+) T cells protect mice against M. tuberculosis independently of IFN-γ. The balance between IFN-γ and different cytokines such as IL-10 and other Th2 cell cytokines is likely to influence disease outcome. Type I IFN appears to be detrimental through at least three separate, but overlapping, type I IFN-mediated mechanisms: induction of excessive apoptosis, specific suppression of Th1 and IFN-γ responses, and dampening of the immune response by strong IL-10 induction. Recently it has been found that M. tuberculosis infection in A549 lung epithelial cells stimulate up-regulation of IFN-λ genes in vitro. IFN-λs also have a role in modulation of Th1/Th2 response. IFN-λs are not essential for M. tuberculosis infection control, but can give some contribution in immune response to this pathogen.

  13. Plant targets for Pseudomonas syringae type III effectors: virulence targets or guarded decoys?

    PubMed

    Block, Anna; Alfano, James R

    2011-02-01

    The phytopathogenic bacterium Pseudomonas syringae can suppress both pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI) by the injection of type III effector (T3E) proteins into host cells. T3Es achieve immune suppression using a variety of strategies including interference with immune receptor signaling, blocking RNA pathways and vesicle trafficking, and altering organelle function. T3Es can be recognized indirectly by resistance proteins monitoring specific T3E targets resulting in ETI. It is presently unclear whether the monitored targets represent bona fide virulence targets or guarded decoys. Extensive overlap between PTI and ETI signaling suggests that T3Es may suppress both pathways through common targets and by possessing multiple activities. PMID:21227738

  14. Pseudomonas syringae type III effector repertoires: last words in endless arguments.

    PubMed

    Lindeberg, Magdalen; Cunnac, Sébastien; Collmer, Alan

    2012-04-01

    Many plant pathogens subvert host immunity by injecting compositionally diverse but functionally similar repertoires of cytoplasmic effector proteins. The bacterial pathogen Pseudomonas syringae is a model for exploring the functional structure of such repertoires. The pangenome of P. syringae encodes 57 families of effectors injected by the type III secretion system. Distribution of effector genes among phylogenetically diverse strains reveals a small set of core effectors targeting antimicrobial vesicle trafficking and a much larger set of variable effectors targeting kinase-based recognition processes. Complete disassembly of the 28-effector repertoire of a model strain and reassembly of a minimal functional repertoire reveals the importance of simultaneously attacking both processes. These observations, coupled with growing knowledge of effector targets in plants, support a model for coevolving molecular dialogs between effector repertoires and plant immune systems that emphasizes mutually-driven expansion of the components governing recognition. PMID:22341410

  15. Lepton flavor violating {tau} decays in the type-III seesaw mechanism

    SciTech Connect

    Arhrib, Abdesslam; Benbrik, Rachid; Chen, C.-H.

    2010-06-01

    In this paper, the lepton flavor violating {tau}{yields}lP(V) (P, V={pi}{sup 0}, {eta}, {eta}{sup '}, {rho}{sup 0}, {omega}, {phi}) and {tau}{yields}3l (l=e, {mu}) decays are studied in the framework of the type-III seesaw model, in which new triplet fermions with a zero hypercharge (Y=0) interact with ordinary lepton doublets via Yukawa couplings, and affect tree-level leptonic Z-boson couplings. We investigate the experimental bound from the leptonic Z decay to get constraints on the existing parameters space. We predict that the upper limits on the branching ratios of {tau}{yields}lP(V) and {tau}{yields}3l can reach the experimental current limits.

  16. Diagnosis and Treatment of a Type III Dens Invagination Using Cone-Beam Computed Tomography

    PubMed Central

    Bahmani, Mohsen; Adl, Alireza; Javanmardi, Samane; Naghizadeh, Sina

    2016-01-01

    A 20-year-old man presented with the history of pain and swelling in the anterior maxillary segment. The periapical radiography was indicative of a dental anomaly in right maxillary lateral incisor. Due to the insufficient information from conventional radiography, cone-beam computed tomography (CBCT) was ordered. CBCT showed apical root resorption, large apical lucency and two separate canals with distinct apical foramen (Oehlers type III dens invagination). The CBCT image was used as a guide for dentine removal with an ultrasonic tip. Conventional root canal therapy was done using lateral compaction technique. One-and two-year follow-up radiographies revealed periapical repair and absence of symptoms. PMID:27790268

  17. The SPI-1-like Type III secretion system: more roles than you think.

    PubMed

    Egan, Frank; Barret, Matthieu; O'Gara, Fergal

    2014-01-01

    The type III secretion system (T3SS) is a protein delivery system which is involved in a wide spectrum of interactions, from mutualism to pathogenesis, between Gram negative bacteria and various eukaryotes, including plants, fungi, protozoa and mammals. Various phylogenetic families of the T3SS have been described, including the Salmonella Pathogenicity Island 1 family (SPI-1). The SPI-1 T3SS was initially associated with the virulence of enteric pathogens, but is actually found in a diverse array of bacterial species, where it can play roles in processes as different as symbiotic interactions with insects and colonization of plants. We review the multiple roles of the SPI-1 T3SS and discuss both how these discoveries are changing our perception of the SPI-1 family and what impacts this has on our understanding of the specialization of the T3SS in general.

  18. Successful stabilisation of a type III paediatric tibial eminence fracture using a tensioned wire technique.

    PubMed

    Archer, Matthew; Parkin, Tom; Latimer, Mark David

    2016-01-01

    We report the case of an 11-year-old boy presenting with a type III tibial eminence fracture. The fracture fragment was reduced arthroscopically. Two 1.6 mm retrograde K-wires were inserted from the tibial metaphysis across the physis and into the fracture fragment using a standard anterior cruciate ligament tibial tunnel guide. Once the wires were clearly visible within the joint the tips were bent over by ∼120°. The wires were then tensioned around a single small fragment screw inserted into the tibial metaphysis. An exceptionally strong fixation was achieved. The boy was mobilised without a brace. The wires were removed at 12 weeks and he returned to full activity at 14 weeks. PMID:27646317

  19. Chemical shift assignments of the fibronectin III like domains 7-8 of type VII collagen.

    PubMed

    Hermsdorf, Ulrike; Seeger, Karsten

    2016-04-01

    Type VII collagen (Col7) is important for skin stability. This is underlined by the severe skin blistering phenotype in the Col7 related diseases dystrophic epidermolysis bullosa and epidermolysis bullosa acquisita (EBA). Col7 has a large N-terminal non-collagenous domain (NC1) that is followed by the triple helical collagenous domain. The NC1 domain has subdomains with homology to adhesion molecules and mediates important interactions within the extracellular matrix. An 185 amino acid long part of the NC1-subdomain termed fibronectin III like domains 7 and 8 (FNIII7-8) was investigated. Antibodies against this region are pathogenic in a mouse model of EBA and one reported missense mutations of Col7 lies within these domains. The nearly complete NMR resonance assignment of recombinant FNIII7-8 of Col7 is reported. PMID:26364055

  20. Kilometer-wave type III burst - Harmonic emission revealed by direction and time of arrival

    NASA Technical Reports Server (NTRS)

    Alvarez, H.; Haddock, F. T.; Potter, W. H.

    1974-01-01

    A type III solar burst was observed at seven frequencies between 3.5 MHz and 80 kHz by the Michigan experiment aboard the IMP-6 satellite. From the data burst direction of arrival as well as time of arrival can be determined. These quantities are predicted, using simple models whose parameters are varied to obtain a good fit to the observations. It is found that between 3.5 MHz and 230 kHz the observed radiation was emitted at the fundamental of the local plasma frequency, while below 230 kHz it was emitted at the second harmonic. The exciter particles that produced the burst onset and burst peak have velocities of 0.27 and 0.12, respectively, in units of the velocity of light.

  1. An Adult Case of Bartter Syndrome Type III Presenting with Proteinuria

    PubMed Central

    Cha, Eun Jung; Hwang, Won Min; Yun, Sung-Ro; Park, Moon Hyang

    2016-01-01

    Bartter syndrome (BS) I–IV is a rare autosomal recessive disorder affecting salt reabsorption in the thick ascending limb of the loop of Henle. This report highlights clinicopathological findings and genetic studies of classic BS in a 22-year-old female patient who presented with persistent mild proteinuria for 2 years. A renal biopsy demonstrated a mild to moderate increase in the mesangial cells and matrix of most glomeruli, along with marked juxtaglomerular cell hyperplasia. These findings suggested BS associated with mild IgA nephropathy. Focal tubular atrophy, interstitial fibrosis, and lymphocytic infiltration were also observed. A genetic study of the patient and her parents revealed a mutation of the CLCNKB genes. The patient was diagnosed with BS, type III. This case represents an atypical presentation of classic BS in an adult patient. Pathologic findings of renal biopsy combined with genetic analysis and clinicolaboratory findings are important in making an accurate diagnosis. PMID:26755355

  2. A clinical report of Type III dens invaginatus: relevant aspects of a combined therapeutic approach.

    PubMed

    Silva E Souza, Patricia de Almeida Rodrigues; de Almeida, Bruno Vila Nova; Tartari, Talita; Alves, Ana Claudia Braga Amoras; Tuji, Farbicio Mesquita; Silva E Souza, Mario Honorato

    2013-01-01

    Dens invaginatus is a developmental abnormality that alters dental morphology; as a result, treating this condition is a challenge for endodontic practices. This article describes how a combination of nonsurgical and surgical therapies was utilized to treat a maxillary central incisor with Type III dens invaginatus and vital pulp. The treatment plan included using computed tomography (CT) for a detailed analysis of the dental anatomy and periapical area, endodontic and surgical procedures, and a 4-year follow-up period that included periodic clinical and radiographic examinations. The follow-up examinations revealed a regression of the apical lesion and no other signs or symptoms. Based on the present case report, the authors concluded that this combination of surgical and nonsurgical approaches was effective and that CT is a valuable auxiliary tool for the study of dental anatomy.

  3. Phase variable type III restriction-modification systems of host-adapted bacterial pathogens.

    PubMed

    Fox, Kate L; Srikhanta, Yogitha N; Jennings, Michael P

    2007-09-01

    Phase variation, the high-frequency on/off switching of gene expression, is a common feature of host-adapted bacterial pathogens. Restriction-modification (R-M) systems, which are ubiquitous among bacteria, are classically assigned the role of cellular defence against invasion of foreign DNA. These enzymes are not obvious candidates for phase variable expression, a characteristic usually associated with surface-expressed molecules subject to host immune selection. Despite this, numerous type III R-M systems in bacterial pathogens contain repetitive DNA motifs that suggest the potential for phase variation. Several roles have been proposed for phase variable R-M systems based on DNA restriction function. However, there is now evidence in several important human pathogens, including Haemophilus influenzae, Neisseria meningitidis and Neisseria gonorrhoeae, that these systems are 'phasevarions' (phase variable regulons) controlling expression of multiple genes via a novel epigenetic mechanism. PMID:17714447

  4. Relationship of Type III Radio Bursts with Quasi-periodic Pulsations in a Solar Flare

    NASA Astrophysics Data System (ADS)

    Kupriyanova, E. G.; Kashapova, L. K.; Reid, H. A. S.; Myagkova, I. N.

    2016-08-01

    We studied a solar flare with pronounced quasi-periodic pulsations detected in the microwave, X-ray, and radio bands. We used correlation, Fourier, and wavelet analyses methods to examine the temporal fine structures and relationships between the time profiles in each wave band. We found that the time profiles of the microwaves, hard X-rays, and type III radio bursts vary quasi-periodically with a common period of 40 - 50 s. The average amplitude of the variations is high, above 30 % of the background flux level, and reaches 80 % after the flare maximum. We did not find this periodicity in either the thermal X-ray flux component or in the source size dynamics. Our findings indicate that the detected periodicity is probably associated with periodic dynamics in the injection of non-thermal electrons, which can be produced by periodic modulation of magnetic reconnection.

  5. On the spectra of type-III solar radio bursts observed at low frequencies

    NASA Technical Reports Server (NTRS)

    Alvarez, H.

    1982-01-01

    The spectra of strong bursts observed at low frequencies by OGO-5 during 1968-1970 are presented. They usually exhibit an intense main peak between 100 kHz and 1 MHz, and sometimes a less intense secondary peak between 1 and 3.5 MHz. Main peaks of 10 to the -12th W per sq m per Hz or more were obtained in very strong events, but because of antenna calibration problems those could be one or two orders of magnitude too high. Recently published work supports the finding that type III bursts at low frequencies can be at least four orders of magnitude more intense than at ground-based frequencies of observation. It is found that the energy received at the earth increases with decreasing frequency approximately as f to the -n, where n is between 3 and 4.

  6. Nonlinear stability of solar type III radio bursts. II - Application to observations near 1 AU

    NASA Technical Reports Server (NTRS)

    Goldstein, M. L.; Smith, R. A.; Papadopoulos, K.

    1979-01-01

    A set of rate equations including strong turbulence effects and anomalous resistivity are solved using parameters which model several solar type III bursts. Analysis of these bursts has led to quantitative comparisons between several of the observed phenomena and the theory. Through use of an analytic model for the time evolution of the energetic electron exciter, it is found that the exciter distributions observed at 1 AU are unstable to the excitation of the linear bump-in-tail instability, amplifying Langmuir waves above the threshold for the oscillating two-stream instability (OTSI). The OTSI and the attendant anomalous resistivity produce a rapid spectral transfer of Langmuir waves to short wavelengths, out of resonance with the electron exciter. In addition, the various parameters needed to model the bursts are extrapolated inside 1 AU with similar results. Finally, reabsorption of the Langmuir waves by the beam is shown to be unimportant in all cases, even at 0.1 AU.

  7. Clinical and radiologic outcomes of surgical and conservative treatment of type III acromioclavicular joint injury.

    PubMed

    Calvo, Emilio; López-Franco, Mariano; Arribas, Ignacio M

    2006-01-01

    The management of acute acromioclavicular joint dislocations is controversial. The purpose of this study was to compare the incidence of posttraumatic anatomic alterations after surgical or conservative treatment of type III injuries and to analyze their effect on the outcome. Forty-three patients were evaluated retrospectively, clinically and radiographically, at a 12-month minimum follow-up. Thirty-two were treated surgically, using the Phemister technique, and 11 had conservative treatment. A comparison of the overall clinical results in both groups showed no statistically significant differences. The acromioclavicular joint was anatomically reduced in only half of the surgical patients. Those shoulders treated surgically showed a significantly higher incidence of osteoarthritis and coracoclavicular ligament ossification. Differences in clavicular deformity or osteolysis were not significant. None of these abnormalities had any influence on the clinical result. Because operative and conservative treatments achieve equally good clinical results and surgery carries a higher risk of osteoarthritis, we recommend managing this injury conservatively.

  8. Opening the Ralstonia solanacearum type III effector tool box: insights into host cell subversion mechanisms.

    PubMed

    Deslandes, Laurent; Genin, Stephane

    2014-08-01

    Effectors delivered to host cells by the Type III secretion system are essential to Ralstonia solanacearum pathogenicity, as in several other plant pathogenic bacteria. The establishment of exhaustive effector repertoires in multiple R. solanacearum strains drew a first picture of the evolutionary dynamics of the pathogen effector suites. Effector repertoires are diversified, with a core of 20-30 effectors present in most of the strains and the obtention of mutants lacking one or more effector genes revealed the functional overlap among this effector network. Recent functional studies have provided insights into the ability of single effectors to manipulate the host proteasome, elicit cell death, trigger the expression of plant genes, and/or display biochemical activities on plant protein targets.

  9. Cutting edge: Mouse NAIP1 detects the type III secretion system needle protein.

    PubMed

    Rayamajhi, Manira; Zak, Daniel E; Chavarria-Smith, Joseph; Vance, Russell E; Miao, Edward A

    2013-10-15

    The NAIP/NLRC4 inflammasomes activate caspase-1 in response to bacterial type III secretion systems (T3SSs). Inadvertent injection of the T3SS rod protein and flagellin into the cytosol is detected through murine NAIP2 and NAIP5/6, respectively. In this study, we identify the agonist for the orphan murine NAIP1 receptor as the T3SS needle protein. NAIP1 is poorly expressed in resting mouse bone marrow-derived macrophages; however, priming with polyinosinic-polycytidylic acid induces it and confers needle protein sensitivity. Further, overexpression of NAIP1 in immortalized bone marrow-derived macrophages by retroviral transduction enabled needle detection. In contrast, peritoneal cavity macrophages basally express NAIP1 and respond to needle protein robustly, independent of priming. Human macrophages are known to express only one NAIP gene, which detects the needle protein, but not rod or flagellin. Thus, murine NAIP1 is functionally analogous to human NAIP. PMID:24043898

  10. Of guards, decoys, baits and traps: pathogen perception in plants by type III effector sensors.

    PubMed

    Khan, Madiha; Subramaniam, Rajagopal; Desveaux, Darrell

    2016-02-01

    Effector-triggered immunity (ETI) is conferred by dominant plant resistance (R) genes, which encode predominantly nucleotide-binding and leucine-rich repeat domain proteins (NLRs), against cognate microbial avirulence (Avr) genes, which include bacterial type III secreted effectors (T3Es). The 'guard model' describes the mechanism of T3E perception by plants, whereby NLRs monitor host proteins ('sensors') for T3E-induced perturbations. This model has provided a molecular framework to understand T3E perception and has rationalized how plants can use a limited number of NLRs (∼160 in Arabidopsis) to contend with a potentially limitless number of evolving effectors. In this review we provide a characteristic overview of plant T3E sensors and discuss how these sensors convey the presence of T3Es to NLR proteins to activate ETI.

  11. A clinical report of Type III dens invaginatus: relevant aspects of a combined therapeutic approach.

    PubMed

    Silva E Souza, Patricia de Almeida Rodrigues; de Almeida, Bruno Vila Nova; Tartari, Talita; Alves, Ana Claudia Braga Amoras; Tuji, Farbicio Mesquita; Silva E Souza, Mario Honorato

    2013-01-01

    Dens invaginatus is a developmental abnormality that alters dental morphology; as a result, treating this condition is a challenge for endodontic practices. This article describes how a combination of nonsurgical and surgical therapies was utilized to treat a maxillary central incisor with Type III dens invaginatus and vital pulp. The treatment plan included using computed tomography (CT) for a detailed analysis of the dental anatomy and periapical area, endodontic and surgical procedures, and a 4-year follow-up period that included periodic clinical and radiographic examinations. The follow-up examinations revealed a regression of the apical lesion and no other signs or symptoms. Based on the present case report, the authors concluded that this combination of surgical and nonsurgical approaches was effective and that CT is a valuable auxiliary tool for the study of dental anatomy. PMID:23302365

  12. Dynamics of Langmuir and ion-sound waves in type III solar radio sources

    NASA Technical Reports Server (NTRS)

    Robinson, P. A.; Willes, A. J.; Cairns, I. H.

    1993-01-01

    The study traces the evolution of Langmuir and ion-sound waves in type III sources, incorporating linear growth, linear damping, and nonlinear electrostatic decay. Improved estimates are obtained for the wavenumber range of growing waves and the nonlinear coupling coefficient for the decay process. It is shown that the conditions in the solar wind do not allow a steady state to be attained; instead, bursty linear and nonlinear interactions take place, consistent with the highly inhomogeneous and impulsive waves actually observed. Nonlinear growth is found to be rapid enough to saturate the growth of the parent Langmuir waves in the available interaction time. The competing processes of nonlinear wave collapse and quasi-linear relaxation are discussed, and it is concluded that neither is responsible for the saturation of Langmuir growth.

  13. Stereoscopic direction finding analysis of a type III solar radio burst - Evidence for emission at 2f/p-/

    NASA Technical Reports Server (NTRS)

    Gurnett, D. A.; Baumback, M. M.; Rosenbauer, H.

    1978-01-01

    Stereoscopic direction finding measurements from the Imp 8, Hawkeye 1, and Helios 2 spacecraft over base line distances of a substantial fraction of an astronomical unit are used to directly determine the three-dimensional trajectory of a type III solar radio burst. By comparing the observed source positions with the direct in situ solar wind plasma density measurements obtained by Helios 1 and 2 near the sun, the relationship of the emission frequency to the local plasma frequency can be determined directly without any modeling assumptions. These comparisons show that the type III radio emission occurs near the second harmonic of the local electron plasma frequency. Other characteristics of the type III radio emission, such as the source size, which can be obtained from this type of analysis, are also discussed.

  14. Sequencing of the gene encoding the major pilin of pilus colonization factor antigen III (CFA/III) of human enterotoxigenic Escherichia coli and evidence that CFA/III is related to type IV pili.

    PubMed Central

    Taniguchi, T; Fujino, Y; Yamamoto, K; Miwatani, T; Honda, T

    1995-01-01

    The plasmid-encoded structural gene cofA necessary for the production of the major pilin subunit of pilus colonization factor antigen III (CFA/III) of human enterotoxigenic Escherichia coli was identified, and the nucleotide sequence of the gene was determined. cofA consists of 714 nucleotides encoding a 238-amino-acid protein (molecular weight of 25,309). CofA seems to be a precursor of CFA/III pilin, because the first 23 residues of the N-terminal amino acid sequence of the purified CFA/III pili coincided with the deduced amino acid sequence for residues 32 to 54 of CofA. Western blot (immunoblot) analysis of CofA also indicated its processing to form mature pilin in the presence of the downstream region of cofA. These results suggest that the major pilin of CFA/III pili is produced as a precursor form which is posttranslationally modified to the mature pilin and forms morphological pili after cleavage of the Gly-30-Met-31 junction, probably by a protease encoded by an as-yet-unknown gene located downstream of cofA. Interestingly, the N-terminal 30-amino-acid sequence of mature CFA/III shows the highest identity (76.7%) to TcpA pilin of Vibrio cholerae, which is a type IV class B pilin. PMID:7822050

  15. Global impact of Salmonella type III secretion effector SteA on host cells

    SciTech Connect

    Cardenal-Muñoz, Elena Gutiérrez, Gabriel Ramos-Morales, Francisco

    2014-07-11

    Highlights: • We analyzed HeLa cells transcriptome in response to Salmonella SteA. • Significant differential expression was detected for 58 human genes. • They are involved in ECM organization and regulation of some signaling pathways. • Cell death, cell adhesion and cell migration were decreased in SteA-expressing cells. • These results contribute to understand the role of SteA during infections. - Abstract: Salmonella enterica is a Gram-negative bacterium that causes gastroenteritis, bacteremia and typhoid fever in several animal species including humans. Its virulence is greatly dependent on two type III secretion systems, encoded in pathogenicity islands 1 and 2. These systems translocate proteins called effectors into eukaryotic host cell. Effectors interfere with host signal transduction pathways to allow the internalization of pathogens and their survival and proliferation inside vacuoles. SteA is one of the few Salmonella effectors that are substrates of both type III secretion systems. Here, we used gene arrays and bioinformatics analysis to study the genetic response of human epithelial cells to SteA. We found that constitutive synthesis of SteA in HeLa cells leads to induction of genes related to extracellular matrix organization and regulation of cell proliferation and serine/threonine kinase signaling pathways. SteA also causes repression of genes related to immune processes and regulation of purine nucleotide synthesis and pathway-restricted SMAD protein phosphorylation. In addition, a cell biology approach revealed that epithelial cells expressing steA show altered cell morphology, and decreased cytotoxicity, cell–cell adhesion and migration.

  16. The impact of Pseudomonas syringae type III effectors on transient protein expression in tobacco.

    PubMed

    Buyel, J F; Buyel, J J; Haase, C; Fischer, R

    2015-03-01

    The production of recombinant proteins in plants is often achieved by transient expression, e.g. following the injection or vacuum infiltration of Agrobacterium tumefaciens into tobacco leaves. We investigated the associated plant defence responses, revealing that callose deposition is triggered by T-DNA transfer and that subsets of secondary metabolites accumulate in response to mechanical wounding or the presence of bacteria. We also tested the ability of five co-expressed type III effector proteins from Pseudomonas syringae to modulate these defence responses and increase the yield of two model proteins, the fluorescent marker DsRed and monoclonal antibody 2G12. HopF2 and AvrRpt2 induced necrotic lesions 5 days post-injection (dpi) even at low doses (OD600 nm  = 0.0078), and increased the concentration of certain secondary metabolites. HopAO1 significantly reduced the number of callose deposits at 2 dpi compared to cells expressing DsRed and 2G12 alone, whereas HopI1 reduced the concentration of several secondary metabolites at 5 dpi compared to cells expressing DsRed and 2G12 alone. Co-expression with HopAO1, AvrPtoB or HopI1 increased the concentrations of DsRed and 2G12 increased by ~6% but this was not a significant change. In contrast, HopF2 and AvrRpt2 significantly reduced the concentrations of DsRed and 2G12 by 34% and 22%, respectively. Our results show that type III effector proteins can modulate plant defence responses and secondary metabolite profiles but that transient co-expression is not sufficient to increase the yields of target recombinant proteins in tobacco.

  17. Structural Analysis of a Specialized Type III Secretion System Peptidoglycan-cleaving Enzyme*

    PubMed Central

    Burkinshaw, Brianne J.; Deng, Wanyin; Lameignère, Emilie; Wasney, Gregory A.; Zhu, Haizhong; Worrall, Liam J.; Finlay, B. Brett; Strynadka, Natalie C.J.

    2015-01-01

    The Gram-negative bacterium enteropathogenic Escherichia coli uses a syringe-like type III secretion system (T3SS) to inject virulence or “effector” proteins into the cytoplasm of host intestinal epithelial cells. To assemble, the T3SS must traverse both bacterial membranes, as well as the peptidoglycan layer. Peptidoglycan is made of repeating N-acetylmuramic acid and N-acetylglucosamine disaccharides cross-linked by pentapeptides to form a tight mesh barrier. Assembly of many macromolecular machines requires a dedicated peptidoglycan lytic enzyme (PG-lytic enzyme) to locally clear peptidoglycan. Here we have solved the first structure of a T3SS-associated PG-lytic enzyme, EtgA from enteropathogenic E. coli. Unexpectedly, the active site of EtgA has features in common with both lytic transglycosylases and hen egg white lysozyme. Most notably, the β-hairpin region resembles that of lysozyme and contains an aspartate that aligns with lysozyme Asp-52 (a residue critical for catalysis), a conservation not observed in other previously characterized lytic transglycosylase families to which the conserved T3SS enzymes had been presumed to belong. Mutation of the EtgA catalytic glutamate, Glu-42, conserved across lytic transglycosylases and hen egg white lysozyme, and this differentiating aspartate diminishes type III secretion in vivo, supporting its essential role in clearing the peptidoglycan for T3SS assembly. Finally, we show that EtgA forms a 1:1 complex with the building block of the polymerized T3SS inner rod component, EscI, and that this interaction enhances PG-lytic activity of EtgA in vitro, collectively providing the necessary strict localization and regulation of the lytic activity to prevent overall cell lysis. PMID:25678709

  18. Appurtenance Influence on Type III Hanford Single-Shell Tank Structural Integrity - 12255

    SciTech Connect

    Sanborn, Scott E.; Johnson, Kenneth I.; Larsen, Brian M.; Julyk, Larry J.

    2012-07-01

    The interim stabilized Hanford Single-Shell Tanks (SSTs) are currently undergoing a state of the art analysis to assess the structural integrity of the waste storage tanks, for cleanup and closure operations, considering their adverse thermal histories and an updated seismic hazard for the Hanford Site near Richland, Washington. The SSTs contain a variety of ancillary pits, piping, piping supports, risers, equipment, and penetrations known as appurtenances. These appurtenances may alter the structural response and ultimately could affect the structural integrity of the SSTs. An important challenge to the structural analysis of the SSTs is to determine the impact of these appurtenances on structural integrity. To achieve this, the various appurtenances were reviewed and a bounding appurtenance configuration for the SST Type III tanks was analyzed using finite element models for both thermal and operating loads as well as seismic loads. Tank structural demands from the finite element analyses were evaluated according to American Concrete Institute (ACI-349) code requirements to determine the tank structural integrity. The appurtenances configuration is found to increase the demand to capacity ratios in local regions near the appurtenances. Away from the appurtenances the influence on structural integrity is minor. The ACI-349-06 evaluation of the Type III SST bounding appurtenance configuration shows the tank is still structurally sound under all evaluated load combinations. When the appurtenance model D/C ratios were compared to those from the baseline axisymmetric model it was found that there were significant differences in the results, particularly under seismic loading conditions. This indicates that the effect of appurtenances on tank structural integrity should at least be considered in all SST AORs. (authors)

  19. A DECADE OF SOLAR TYPE III RADIO BURSTS OBSERVED BY THE NANCAY RADIOHELIOGRAPH 1998-2008

    SciTech Connect

    Saint-Hilaire, P.; Vilmer, N.; Kerdraon, A.

    2013-01-01

    We present a statistical survey of almost 10,000 radio type III bursts observed by the Nancay Radioheliograph from 1998 to 2008, covering nearly a full solar cycle. In particular, sources sizes, positions, and fluxes were examined. We find an east-west asymmetry in source positions that could be attributed to a 6 Degree-Sign {+-} 1 Degree-Sign eastward tilt of the magnetic field, that source FWHM sizes s roughly follow a solar-cycle-averaged distribution (dN/ds) Almost-Equal-To 14 {nu}{sup -3.3} s {sup -4} arcmin{sup -1} day{sup -1}, and that source fluxes closely follow a solar-cycle-averaged (dN/ds {sub {nu}}) Almost-Equal-To 0.34 {nu}{sup -2.9} S {sup -1.7} {sub {nu}} sfu{sup -1} day{sup -1} distribution (when {nu} is in GHz, s in arcminutes, and S {sub {nu}} in sfu). Fitting a barometric density profile yields a temperature of 0.6 MK, while a solar wind-like ({proportional_to}h {sup -2}) density profile yields a density of 1.2 Multiplication-Sign 10{sup 6} cm{sup -3} at an altitude of 1 R{sub S} , assuming harmonic emission. Finally, we found that the solar-cycle-averaged radiated type III energy could be similar in magnitude to that radiated by nanoflares via non-thermal bremsstrahlung processes, and we hint at the possibility that escaping electron beams might carry as much energy away from the corona as is introduced into it by accelerated nanoflare electrons.

  20. Observational Characteristics of Langmuir Turbulence Associated with Solar Type III Radio Bursts

    NASA Astrophysics Data System (ADS)

    Golla, T.; MacDowall, R. J.

    2015-12-01

    Solar flares present the most dramatic energy releases from the Sun. The solar flares accelerate electrons, which form bump-on-tail distributions, and excite electrostatic waves called Langmuir waves, which are subsequently converted into escaping radiation at the fundamental and second harmonic of the electron plasma frequency by some nonlinear processes. These radio emissions are called the type III radio bursts. The sources of these bursts represent natural laboratories of beam-plasma systems. The WAVES experiment on the STEREO spacecraft contains an improved Time Domain Sampler (TDS), improved over that of all similar high time resolution receivers flown in earlier spacecraft. It is primarily intended for the study of Langmuir waves. These in situ high time resolution wave measurements enable us to identify and understand the physical processes associated with beam-plasma systems, as well as for conversion of Langmuir waves into escaping radiation at the fundamental and second harmonic of the electron plasma frequency. The waveforms captured by the TDS usually contain a variety of distortions caused by various nonlinear processes. The normalized peak intensities, wave numbers and spectral widths of these wave packets determine the nonlinear processes, which control the evolution of these wave packets. We have analyzed the in situ high time resolution measurements of Langmuir wave packets and determined their three dimensional relative peak intensities, spectral components and spectral widths. Using the frequency drifts of the type III bursts, we have estimated the velocities of the electron beams which in turn yielded the corresponding wave numbers. We will present the distributions of these important physical quantities and their implications for the theoretical models.

  1. Treatment of Rockwood type III acromioclavicular joint dislocation using autogenous semitendinosus tendon graft and endobutton technique

    PubMed Central

    Ye, Gang; Peng, Chao-An; Sun, Hua-Bin; Xiao, Jing; Zhu, Kang

    2016-01-01

    Background The aim of this study was to evaluate the therapeutic effect of autogenous semitendinosus graft and endobutton technique, and compare with hook plate in treatment of Rockwood type III acromioclavicular (AC) joint dislocation. Methods From April 2012 to April 2013, we treated 46 patients with Rockwood type III AC joint dislocation. Patients were randomly divided into two groups: Group A was treated using a hook plate and Group B with autogenous semitendinosus graft and endobutton technique. All participants were followed up for 12 months. Radiographic examinations were performed every 2 months postoperatively, and clinical evaluation was performed using the Constant–Murley score at the last follow-up. Results Results indicated that patients in Group B showed higher mean scores (90.3±5.4) than Group A (80.4±11.5) in terms of Constant–Murley score (P=0.001). Group B patients scored higher in terms of pain (P=0.002), activities (P=0.02), range of motion (P<0.001), and strength (P=0.004). In Group A, moderate pain was reported by 2 (8.7%) and mild pain by 8 (34.8%) patients. Mild pain was reported by 1 (4.3%) patient in Group B. All patients in Group B maintained complete reduction, while 2 (8.7%) patients in Group A experienced partial reduction loss. Two patients (8.7%) encountered acromial osteolysis on latest radiographs, with moderate shoulder pain and limited range of motion. Conclusion Autogenous semitendinosus graft and endobutton technique showed better results compared with the hook plate method and exhibited advantages of fewer complications such as permanent pain and acromial osteolysis. PMID:26811685

  2. Amiloride-Insensitive Salt Taste Is Mediated by Two Populations of Type III Taste Cells with Distinct Transduction Mechanisms

    PubMed Central

    Sukumaran, Sunil K.; Margolskee, Robert F.; Bachmanov, Alexander A.

    2016-01-01

    Responses in the amiloride-insensitive (AI) pathway, one of the two pathways mediating salty taste in mammals, are modulated by the size of the anion of a salt. This “anion effect” has been hypothesized to result from inhibitory transepithelial potentials (TPs) generated across the lingual epithelium as cations permeate through tight junctions and leave their larger and less permeable anions behind (Ye et al., 1991). We tested directly the necessity of TPs for the anion effect by measuring responses to NaCl and Na-gluconate (small and large anion sodium salts, respectively) in isolated taste cells from mouse circumvallate papillae. Using calcium imaging, we identified AI salt-responsive type III taste cells and demonstrated that they compose a subpopulation of acid-responsive taste cells. Even in the absence of TPs, many (66%) AI salt-responsive type III taste cells still exhibited the anion effect, demonstrating that some component of the transduction machinery for salty taste in type III cells is sensitive to anion size. We hypothesized that osmotic responses could explain why a minority of type III cells (34%) had AI salt responses but lacked anion sensitivity. All AI type III cells had osmotic responses to cellobiose, which were significantly modulated by extracellular sodium concentration, suggesting the presence of a sodium-conducting osmotically sensitive ion channel. However, these responses were significantly larger in AI type III cells that did not exhibit the anion effect. These findings indicate that multiple mechanisms could underlie AI salt responses in type III taste cells, one of which may contribute to the anion effect. SIGNIFICANCE STATEMENT Understanding the mechanisms underlying salty taste will help inform strategies to combat the health problems associated with NaCl overconsumption by humans. Of the two pathways underlying salty taste in mammals, the amiloride-insensitive (AI) pathway is the least understood. Using calcium imaging of

  3. Comparative analysis of the secretion capability of early and late flagellar type III secretion substrates

    PubMed Central

    Singer, Hanna M.; Erhardt, Marc; Hughes, Kelly T.

    2016-01-01

    Summary A remarkable feature of the flagellar-specific type III secretion system (T3SS) is the selective recognition of a few substrate proteins among the many thousand cytoplasmic proteins. Secretion substrates are divided into two specificity classes: early substrates secreted for hook-basal body (HBB) construction and late substrates secreted after HBB completion. Secretion was reported to require a disordered N-terminal secretion signal, mRNA secretion signals within the 5′-untranslated region (5′-UTR) and for late substrates, piloting proteins known as the T3S chaperones. Here, we utilized translational β-lactamase fusions to probe the secretion efficacy of the N-terminal secretion signal of fourteen secreted flagellar substrates in Salmonella enterica. We observed a surprising variety in secretion capability between flagellar proteins of the same secretory class. The peptide secretion signals of the early-type substrates FlgD, FlgF, FlgE and the late-type substrate FlgL were analysed in detail. Analysing the role of the 5′-UTR in secretion of flgB and flgE revealed that the native 5′-UTR substantially enhanced protein translation and secretion. Based on our data, we propose a multicomponent signal that drives secretion via the flagellar T3SS. Both mRNA and peptide signals are recognized by the export apparatus and together with substrate-specific chaperones allowing for targeted secretion of flagellar substrates. PMID:24946091

  4. TEM observations on Type III kerogen, with special reference to coal as a source rock

    NASA Astrophysics Data System (ADS)

    Liu, Susie Y.; Taylor, Geoff H.

    Type III kerogen follows the coalification track of vitrinite or a bulk coal. It is often inferred that, because this organic matter is of comparatively low hydrogen and high oxygen content, it cannot be more than a marginal source of petroleum. This is not a correct approach because the actual source material is not the whole coal but only a small fraction. Some, at least, of this small fraction appears likely to be just as rich a source as much of Type I or Type II kerogen. There is no doubt that the liptinite macerals are important source materials. However, with TEM it can be shown that there are additional, and in some cases more significant, sources with varying degrees of thermal reactivity. These include: -in vitrinite, the remains of fungi and bacteria, other fine lipid-rich matter, and suberin; -in vitrinitic and especially in inertinitic coal, algal and algae-like material. Micrinite consists of aggregates of very fine spherical bodies which are formed when hydrocarbons are generated. The presence of such aggregates within the coal texture confirms the generative role of the lipid-rich components and provides an important indication as to whether generation has occurred.

  5. Type I/II cytokines, JAKs, and new strategies for treating autoimmune diseases

    PubMed Central

    Schwartz, Daniella M.; Bonelli, Michael; Gadina, Massimo; O’Shea, John J.

    2015-01-01

    Cytokines are major drivers of autoimmunity, and biologic agents targeting cytokines have revolutionized the treatment of immune-mediated diseases. Despite the effectiveness of these drugs, they do not induce complete remission in all patients, prompting the development of alternative strategies—including targeting of intracellular signal transduction pathways downstream of cytokines. Many cytokines that bind type I and type II cytokine receptors are critical regulators of immune-mediated diseases and employ the Janus kinase (JAK) and signal transducer and activator of transcription (STAT) pathway to exert their effect. Pharmacological inhibition of JAKs block the actions of type I/II cytokines, and within the past 3 years therapeutic JAK inhibitors, or Jakinibs, have become available to rheumatologists. Jakinibs have proven effective for the treatment of rheumatoid arthritis and other inflammatory diseases. Adverse effects of these agents are largely related to their mode of action and include infections and hyperlipidemia. Jakinibs are currently being investigated for a number of new indications, and second-generation selective Jakinibs are being developed and tested. Targeting STATs could be a future avenue for the treatment of rheumatic diseases, although substantial challenges remain. Nonetheless, the ability to therapeutically target intracellular signalling pathways has already created a new paradigm for the treatment of rheumatologic disease. PMID:26633291

  6. Human NAIP and mouse NAIP1 recognize bacterial type III secretion needle protein for inflammasome activation.

    PubMed

    Yang, Jieling; Zhao, Yue; Shi, Jianjin; Shao, Feng

    2013-08-27

    Inflammasome mediated by central nucleotide-binding and oligomerization domain (NOD)-like receptor (NLR) protein is critical for defense against bacterial infection. Here we show that type III secretion system (T3SS) needle proteins from several bacterial pathogens, including Salmonella typhimurium, enterohemorrhagic Escherichia coli, Shigella flexneri, and Burkholderia spp., can induce robust inflammasome activation in both human monocyte-derived and mouse bone marrow macrophages. Needle protein activation of human NRL family CARD domain containing 4 (NLRC4) inflammasome requires the sole human neuronal apoptosis inhibitory protein (hNAIP). Among the seven mouse NAIPs, NAIP1 functions as the mouse counterpart of hNAIP. We found that NAIP1 recognition of T3SS needle proteins was more robust in mouse dendritic cells than in bone marrow macrophages. Needle proteins, as well as flagellin and rod proteins from five different bacteria, exhibited differential and cell type-dependent inflammasome-stimulating activity. Comprehensive profiling of the three types of NAIP ligands revealed that NAIP1 sensing of the needle protein dominated S. flexneri-induced inflammasome activation, particularly in dendritic cells. hNAIP/NAIP1 and NAIP2/5 formed a large oligomeric complex with NLRC4 in the presence of corresponding bacterial ligands, and could support reconstitution of the NLRC4 inflammasome in a ligand-specific manner. PMID:23940371

  7. Human NAIP and mouse NAIP1 recognize bacterial type III secretion needle protein for inflammasome activation

    PubMed Central

    Yang, Jieling; Zhao, Yue; Shi, Jianjin; Shao, Feng

    2013-01-01

    Inflammasome mediated by central nucleotide-binding and oligomerization domain (NOD)-like receptor (NLR) protein is critical for defense against bacterial infection. Here we show that type III secretion system (T3SS) needle proteins from several bacterial pathogens, including Salmonella typhimurium, enterohemorrhagic Escherichia coli, Shigella flexneri, and Burkholderia spp., can induce robust inflammasome activation in both human monocyte-derived and mouse bone marrow macrophages. Needle protein activation of human NRL family CARD domain containing 4 (NLRC4) inflammasome requires the sole human neuronal apoptosis inhibitory protein (hNAIP). Among the seven mouse NAIPs, NAIP1 functions as the mouse counterpart of hNAIP. We found that NAIP1 recognition of T3SS needle proteins was more robust in mouse dendritic cells than in bone marrow macrophages. Needle proteins, as well as flagellin and rod proteins from five different bacteria, exhibited differential and cell type-dependent inflammasome-stimulating activity. Comprehensive profiling of the three types of NAIP ligands revealed that NAIP1 sensing of the needle protein dominated S. flexneri-induced inflammasome activation, particularly in dendritic cells. hNAIP/NAIP1 and NAIP2/5 formed a large oligomeric complex with NLRC4 in the presence of corresponding bacterial ligands, and could support reconstitution of the NLRC4 inflammasome in a ligand-specific manner. PMID:23940371

  8. Accumulation of properly folded human type III procollagen molecules in specific intracellular membranous compartments in the yeast Pichia pastoris.

    PubMed

    Keizer-Gunnink, I; Vuorela, A; Myllyharju, J; Pihlajaniemi, T; Kivirikko, K I; Veenhuis, M

    2000-02-01

    It was recently reported that co-expression of the proalpha1(III) chain of human type III procollagen with the subunits of human prolyl 4-hydroxylase in Pichia pastoris produces fully hydroxylated and properly folded recombinant type III procollagen molecules (Vuorela, A., Myllyharju, J., Nissi, R., Pihlajaniemi, T., Kivirikko, K.I., 1997. Assembly of human prolyl 4-hydroxylase and type III collagen in the yeast Pichia pastoris: formation of a stable enzyme tetramer requires coexpression with collagen and assembly of a stable collagen requires coexpression with prolyl 4-hydroxylase. EMBO J. 16, 6702-6712). These properly folded molecules accumulated inside the yeast cell, however, only approximately 10% were found in the culture medium. We report here that replacement of the authentic signal sequence of the human proalpha1(III) with the Saccharomyces cerevisiae alpha mating factor prepro sequence led only to a minor increase in the amount secreted. Immunoelectron microscopy studies indicated that the procollagen molecules accumulate in specific membranous vesicular compartments that are closely associated with the nuclear membrane. Prolyl 4-hydroxylase, an endoplasmic reticulum (ER) lumenal enzyme, was found to be located in the same compartments. Non-helical proalpha1(III) chains produced by expression without recombinant prolyl 4-hydroxylase likewise accumulated within these compartments. The data indicate that properly folded recombinant procollagen molecules accumulate within the ER and do not proceed further in the secretory pathway. This may be related to the large size of the procollagen molecule. PMID:10686423

  9. Should Splenic Hilar Lymph Nodes be Dissected for Siewert Type II and III Esophagogastric Junction Carcinoma Based on Tumor Diameter?

    PubMed Central

    Lv, Chen-Bin; Huang, Chang-Ming; Zheng, Chao-Hui; Li, Ping; Xie, Jian-Wei; Wang, Jia-Bin; Lin, Jian-Xian; Lu, Jun; Chen, Qi-Yue; Cao, Long-Long; Lin, Mi; Tu, Ru-Hong

    2016-01-01

    Abstract The aim of the study is to identify the value of a spleen-preserving No. 10 lymphadenectomy (SPL) for Siewert type II/III adenocarcinoma of the esophagogastric junction (AEG). From January 2007 to June 2014, 694 patients undergoing radical total gastrectomy for Siewert type II/III AEG were analyzed. Oncologic outcomes were compared between SPL and no SPL (No. 10D+ and No. 10D–) groups. The incidence of No. 10 lymph node metastasis (LNM) was 12.3%. No significant differences in the incidence of No. 10 LNM were found between Siewert type II AEG with tumor diameters of <4 cm and ≥4 cm (P = 0.071). However, Siewert type III AEG with a tumor diameter ≥4 cm showed a significantly higher frequency of No. 10 LNM compared with a tumor diameter <4 cm (P < 0.001). The No. 10D+ group had superior 3-year overall survival (OS) and disease-free survival (DFS) rates compared with the No. 10D− group (P = 0.030 and P = 0.005, respectively). For patients with Siewert type II and type III AEG with a tumor diameter <4 cm, the 3-year OS and DFS rates were similar between the 2 groups. However, the No. 10D+ group had better 3-year OS (66.6% vs 51.1%, P = 0.019) and DFS (63.2% vs 45.9%, P = 0.007) rates for Siewert type III AEG with a tumor diameter ≥4 cm. A multivariate Cox regression showed that SPL was an independent prognostic factor in Siewert type III AEG with a tumor diameter ≥4 cm. SPL may improve the prognosis of Siewert type III AEG with a tumor diameter ≥4 cm, whereas SPL may be omitted without decreasing survival in patients with Siewert type II or type III AEG with a tumor diameter <4 cm. PMID:27227913

  10. On the radio wave group delay in the solar corona for the case of decameter type III bursts

    NASA Astrophysics Data System (ADS)

    Itkina, M. A.; Levin, B. N.; Tsybko, Ya. G.

    1993-11-01

    The excess time delay of the radio waves during their propagation through inhomogeneous plasma is due to two main reasons: (1) the electromagnetic wave group velocity differs from its vacuum value; (2) the ray path is lengthened by refraction. The group delay of type IIIb-III burst emission is estimated by analyzing observations made with the UTR-2 array (Abranin et al. 1984). Owing to the harmonic origin of the type IIIb-III events it is possible to probe one and the same coronal region at two largely different frequencies. The group delay effect has to be more significant for the fundamental emission (type IIIb burst) than for the second harmonic (type III burst). For the observed type IIIb-III pairs this difference is found smaller than the uncertainties in the data. The group delay time for the fundamental emission in the frequency range 12.5-6.25 MHz does not exceed 1 s and the differential group delay is less than 0.3-0.5 s with a degree of confidence of approximately 70%. Radio wave propagation through the coronal plasma is simulated numerically choosing the scale height of the coronal density which fits the mean frequency drift rate of the observed type IIIb-III bursts. The calculated group delay times are found considerably larger than the observed ones if the mean velocity vs of the burst source is assumed equal to 0.3 c. It is possible to reconcile the experimental and calculated group delay times choosing vs less than or equal to 0.1 c. Another possibility is to assume that the fundamental type III emission is produced by the coalescence of plasma (Langmuir) waves with low frequency waves instead of plasma wave Rayleigh scattering by thermal ions.

  11. Oblique Axis Body Fracture: An Unstable Subtype of Anderson Type III Odontoid Fractures-Apropos of Two Cases.

    PubMed

    Takai, Hirokazu; Konstantinidis, Lukas; Schmal, Hagen; Helwig, Peter; Knöller, Stefan; Südkamp, Norbert; Hauschild, Oliver

    2016-01-01

    Purpose. Anderson type III odontoid fractures have traditionally been considered stable and treated conservatively. However, unstable cases with unfavorable results following conservative treatment have been reported. Methods. We present the cases of two patients who sustained minimally displaced Anderson type III fractures with a characteristic fracture pattern that we refer to as "oblique type axis body fracture." Results. The female patients aged 90 and 72 years, respectively, were both diagnosed with minimally displaced Anderson type III fractures. Both fractures had a characteristic "oblique type" fracture pattern. The first patient was treated conservatively with cervical spine immobilization in a semirigid collar. However, gross displacement was noted at the 6-week follow-up visit. The second patient was therefore treated operatively by C1-C3/4 posterior fusion and the course was uneventful. Conclusions. Oblique type axis body fractures resemble a highly unstable subtype of Anderson type III fractures with the potential of severe secondary deformity following conservative treatment, irrespective of initial grade of displacement. The authors therefore warrant a high index of suspicion for this injury and suggest early operative stabilization. PMID:27042372

  12. Detection of fundamental and harmonic type III radio emission and the associated Langmuir waves at the source region

    NASA Technical Reports Server (NTRS)

    Reiner, M. J.; Stone, R. G.; Fainberg, J.

    1992-01-01

    Type III radio emission generated in the vicinity of the Ulysses spacecraft has been detected at both the fundamental and harmonic of the local plasma frequency. The observations represent the first clear evidence of locally generated type III radio emission. This local emission shows no evidence of frequency drift, exhibits a relatively short rise time, is less intense than the observed remotely generated radio emission, and is temporally correlated with observed in situ Langmuir waves. The observations were made with the unified radio astronomy and wave (URAP) experiment on the Ulysses spacecraft between 1990 November 4 and 1991 April 30, as it traveled from 1 to 3 AU from the sun. During this time period many thousands of bursts were observed. However, only three examples of local emission and associated Langmuir waves were identified. This supports previous suggestions that type III radio emission is generated in localized regions of the interplanetary medium, rather than uniformly along the extent of the electron exciter beam.

  13. FLARE-ASSOCIATED TYPE III RADIO BURSTS AND DYNAMICS OF THE EUV JET FROM SDO/AIA AND RHESSI OBSERVATIONS

    SciTech Connect

    Chen Naihwa; Ip, Wing-Huen; Innes, Davina E-mail: wingip@astro.ncu.edu.tw

    2013-06-01

    We present a detailed description of the interrelation between the Type III radio bursts and energetic phenomena associated with the flare activities in active region AR11158 at 07:58 UT on 2011 February 15. The timing of the Type III radio burst measured by the radio wave experiment on Wind/WAVE and an array of ground-based radio telescopes coincided with an extreme-ultraviolet (EUV) jet and hard X-ray (HXR) emission observed by SDO/AIA and RHESSI, respectively. There is clear evidence that the EUV jet shares the same source region as the HXR emission. The temperature of the jet, as determined by multiwavelength measurements by Atmospheric Imaging Assembly, suggests that Type III emission is associated with hot, 7 MK, plasma at the jet's footpoint.

  14. Immunohistochemical expression of types I and III collagen antibodies in the temporomandibular joint disc of human foetuses

    PubMed Central

    de Moraes, L.O.C.; Lodi, F.R.; Gomes, T.S.; Marques, S.R.; Oshima, C.T.F.; Lancellotti, C.L.P.; Rodríguez-Vázquez, J.F.; Mérida-Velasco, J.R.; Alonso, L.G.

    2011-01-01

    The objective was to study the morphology of the articular disc and analyse the immunohistochemical expression of types I and III collagen markers in the temporomandibular joint (TMJ) disc of human foetuses of different gestational ages. Twenty TMJ from human foetuses supplied by Universidade Federal de Uberaba with gestational ages from 17 to 24 weeks were studied. The gestational age of the foetuses was determined by measuring the crown-rump (CR) length. Macroscopically, the foetuses were fixed in 10% formalin solution and dissected by removing the skin and subcutaneous tissue and exposing the deep structures. Immunohistochemical markers of type I and III were used to characterize the existence of collagen fibres. Analysis of the immunohistochemical markers of types I and III collagen revealed the presence of heterotypical fibril networks. PMID:22073371

  15. Immunohistochemical expression of types I and III collagen antibodies in the temporomandibular joint disc of human foetuses.

    PubMed

    de Moraes, L O C; Lodi, F R; Gomes, T S; Marques, S R; Oshima, C T F; Lancellotti, C L P; Rodríguez-Vázquez, J F; Mérida-Velasco, J R; Alonso, L G

    2011-01-01

    The objective was to study the morphology of the articular disc and analyse the immunohistochemical expression of types I and III collagen markers in the temporomandibular joint (TMJ) disc of human foetuses of different gestational ages. Twenty TMJ from human foetuses supplied by Universidade Federal de Uberaba with gestational ages from 17 to 24 weeks were studied. The gestational age of the foetuses was determined by measuring the crown-rump (CR) length. Macroscopically, the foetuses were fixed in 10% formalin solution and dissected by removing the skin and subcutaneous tissue and exposing the deep structures. Immunohistochemical markers of type I and III were used to characterize the existence of collagen fibres. Analysis of the immunohistochemical markers of types I and III collagen revealed the presence of heterotypical fibril networks.

  16. The Bacterial Alarmone (p)ppGpp Activates the Type III Secretion System in Erwinia amylovora

    PubMed Central

    Ancona, Veronica; Lee, Jae Hoon; Chatnaparat, Tiyakhon; Oh, Jinrok; Hong, Jong-In

    2015-01-01

    ABSTRACT The hypersensitive response and pathogenicity (hrp) type III secretion system (T3SS) is a key pathogenicity factor in Erwinia amylovora. Previous studies have demonstrated that the T3SS in E. amylovora is transcriptionally regulated by a sigma factor cascade. In this study, the role of the bacterial alarmone ppGpp in activating the T3SS and virulence of E. amylovora was investigated using ppGpp mutants generated by Red recombinase cloning. The virulence of a ppGpp-deficient mutant (ppGpp0) as well as a dksA mutant of E. amylovora was completely impaired, and bacterial growth was significantly reduced, suggesting that ppGpp is required for full virulence of E. amylovora. Expression of T3SS genes was greatly downregulated in the ppGpp0 and dksA mutants. Western blotting showed that accumulations of the HrpA protein in the ppGpp0 and dksA mutants were about 10 and 4%, respectively, of that in the wild-type strain. Furthermore, higher levels of ppGpp resulted in a reduced cell size of E. amylovora. Moreover, serine hydroxamate and α-methylglucoside, which induce amino acid and carbon starvation, respectively, activated hrpA and hrpL promoter activities in hrp-inducing minimal medium. These results demonstrated that ppGpp and DksA play central roles in E. amylovora virulence and indicated that E. amylovora utilizes ppGpp as an internal messenger to sense environmental/nutritional stimuli for regulation of the T3SS and virulence. IMPORTANCE The type III secretion system (T3SS) is a key pathogenicity factor in Gram-negative bacteria. Fully elucidating how the T3SS is activated is crucial for comprehensively understanding the function of the T3SS, bacterial pathogenesis, and survival under stress conditions. In this study, we present the first evidence that the bacterial alarmone ppGpp-mediated stringent response activates the T3SS through a sigma factor cascade, indicating that ppGpp acts as an internal messenger to sense environmental/nutritional stimuli for

  17. Collider signatures for the heavy lepton triplet in the type I+III seesaw mechanism

    SciTech Connect

    Arhrib, Abdesslam; Bajc, Borut; Ghosh, Dilip Kumar; Han, Tao; Huang, Gui-Yu; Puljak, Ivica; Senjanovic, Goran

    2010-09-01

    The minimal SU(5) theory augmented by the fermionic adjoint representation restores the coupling constant unification and gives realistic neutrino masses and mixing through the hybrid Type I and Type III seesaw. The crucial prediction of the theory is an SU(2) lepton triplet with the mass below TeV. We study the signature of these heavy leptons at the hadron and lepton colliders. The smoking gun evidence of the theory, as in general seesaw mechanisms, is {Delta}L=2 lepton-number violation through events of a pair of like-sign leptons plus four jets without significant missing energy at hadron colliders. We find that via this unique channel the heavy lepton can be searched for up to a mass of 200 GeV at the Tevatron with 8 fb{sup -1}, and up to 450 (700) GeV at the LHC of 14 TeV C.M. energy with 10(100) fb{sup -1}. The 7 TeV LHC run of 1 fb{sup -1} is expected to probe a mass window of 110-200 GeV. We also comment on how to distinguish this theory from other models with similar heavy leptons. Finally, we compare the production rates and angular distributions of heavy leptons in e{sup +}e{sup -} collisions for various models.

  18. Defective glycosylation of coagulation factor XII underlies hereditary angioedema type III

    PubMed Central

    Björkqvist, Jenny; de Maat, Steven; Lewandrowski, Urs; Di Gennaro, Antonio; Oschatz, Chris; Schönig, Kai; Nöthen, Markus M.; Drouet, Christian; Braley, Hal; Nolte, Marc W.; Sickmann, Albert; Panousis, Con; Maas, Coen; Renné, Thomas

    2015-01-01

    Hereditary angioedema type III (HAEIII) is a rare inherited swelling disorder that is associated with point mutations in the gene encoding the plasma protease factor XII (FXII). Here, we demonstrate that HAEIII-associated mutant FXII, derived either from HAEIII patients or recombinantly produced, is defective in mucin-type Thr309-linked glycosylation. Loss of glycosylation led to increased contact-mediated autoactivation of zymogen FXII, resulting in excessive activation of the bradykinin-forming kallikrein-kinin pathway. In contrast, both FXII-driven coagulation and the ability of C1-esterase inhibitor to bind and inhibit activated FXII were not affected by the mutation. Intravital laser-scanning microscopy revealed that, compared with control animals, both F12–/– mice reconstituted with recombinant mutant forms of FXII and humanized HAEIII mouse models with inducible liver-specific expression of Thr309Lys-mutated FXII exhibited increased contact-driven microvascular leakage. An FXII-neutralizing antibody abolished bradykinin generation in HAEIII patient plasma and blunted edema in HAEIII mice. Together, the results of this study characterize the mechanism of HAEIII and establish FXII inhibition as a potential therapeutic strategy to interfere with excessive vascular leakage in HAEIII and potentially alleviate edema due to other causes. PMID:26193639

  19. Engineering the Salmonella type III secretion system to export spider silk monomers.

    PubMed

    Widmaier, Daniel M; Tullman-Ercek, Danielle; Mirsky, Ethan A; Hill, Rena; Govindarajan, Sridhar; Minshull, Jeremy; Voigt, Christopher A

    2009-01-01

    The type III secretion system (T3SS) exports proteins from the cytoplasm, through both the inner and outer membranes, to the external environment. Here, a system is constructed to harness the T3SS encoded within Salmonella Pathogeneity Island 1 to export proteins of biotechnological interest. The system is composed of an operon containing the target protein fused to an N-terminal secretion tag and its cognate chaperone. Transcription is controlled by a genetic circuit that only turns on when the cell is actively secreting protein. The system is refined using a small human protein (DH domain) and demonstrated by exporting three silk monomers (ADF-1, -2, and -3), representative of different types of spider silk. Synthetic genes encoding silk monomers were designed to enhance genetic stability and codon usage, constructed by automated DNA synthesis, and cloned into the secretion control system. Secretion rates up to 1.8 mg l(-1) h(-1) are demonstrated with up to 14% of expressed protein secreted. This work introduces new parts to control protein secretion in Gram-negative bacteria, which will be broadly applicable to problems in biotechnology. PMID:19756048

  20. Erwinia amylovora secretes harpin via a type III pathway and contains a homolog of yopN of Yersinia spp.

    PubMed Central

    Bogdanove, A J; Wei, Z M; Zhao, L; Beer, S V

    1996-01-01

    Type III secretion functions in flagellar biosynthesis and in export of virulence factors from several animal pathogens, and for plant pathogens, it has been shown to be involved in the export of elicitors of the hypersensitive reaction. Typified by the Yop delivery system of Yersinia spp., type III secretion is sec independent and requires multiple components. Sequence analysis of an 11.5-kb region of the hrp gene cluster of Erwinia amylovora containing hrpI, a previously characterized type III gene, revealed a group of eight or more type III genes corresponding to the virB or lcrB (yscN-to-yscU) locus of Yersinia spp. A homolog of another Yop secretion gene, yscD, was found between hrpI and this group downstream. Immediately upstream of hrpI, a homolog of yopN was discovered. yopN is a putative sensor involved in host-cell-contact-triggered expression and transfer of protein, e.g., YopE, to the host cytoplasm. In-frame deletion mutagenesis of one of the type III genes, designated hrcT, was nonpolar and resulted in a Hrp- strain that produced but did not secrete harpin, an elicitor of the hypersensitive reaction that is also required for pathogenesis. Cladistic analysis of the HrpI (herein renamed HrcV) or LcrD protein family revealed two distinct groups for plant pathogens. The Yersinia protein grouped more closely with the plant pathogen homologs than with homologs from other animal pathogens; flagellar biosynthesis proteins grouped distinctly. A possible evolutionary history of type III secretion is presented, and the potential significance of the similarity between the harpin and Yop export systems is discussed, particularly with respect to a potential role for the YopN homolog in pathogenesis of plants. PMID:8626302

  1. Oblique Axis Body Fracture: An Unstable Subtype of Anderson Type III Odontoid Fractures—Apropos of Two Cases

    PubMed Central

    Konstantinidis, Lukas; Schmal, Hagen; Helwig, Peter; Knöller, Stefan; Südkamp, Norbert; Hauschild, Oliver

    2016-01-01

    Purpose. Anderson type III odontoid fractures have traditionally been considered stable and treated conservatively. However, unstable cases with unfavorable results following conservative treatment have been reported. Methods. We present the cases of two patients who sustained minimally displaced Anderson type III fractures with a characteristic fracture pattern that we refer to as “oblique type axis body fracture.” Results. The female patients aged 90 and 72 years, respectively, were both diagnosed with minimally displaced Anderson type III fractures. Both fractures had a characteristic “oblique type” fracture pattern. The first patient was treated conservatively with cervical spine immobilization in a semirigid collar. However, gross displacement was noted at the 6-week follow-up visit. The second patient was therefore treated operatively by C1–C3/4 posterior fusion and the course was uneventful. Conclusions. Oblique type axis body fractures resemble a highly unstable subtype of Anderson type III fractures with the potential of severe secondary deformity following conservative treatment, irrespective of initial grade of displacement. The authors therefore warrant a high index of suspicion for this injury and suggest early operative stabilization. PMID:27042372

  2. Strains of the Propionibacterium acnes type III lineage are associated with the skin condition progressive macular hypomelanosis.

    PubMed

    Barnard, Emma; Liu, Jared; Yankova, Eliza; Cavalcanti, Silvana M; Magalhães, Marcelo; Li, Huiying; Patrick, Sheila; McDowell, Andrew

    2016-01-01

    Progressive macular hypomelanosis (PMH) is a common skin disorder that causes hypopigmentation in a variety of skin types. Although the underlying aetiology of this condition is unclear, there is circumstantial evidence that links the skin bacterium Propionibacterium acnes to the condition. We now describe the first detailed population genetic analysis of P. acnes isolates recovered from paired lesional and non-lesional skin of PMH patients. Our results demonstrate a strong statistical association between strains from the type III phylogenetic lineage and PMH lesions (P = 0.0019), but not those representing other phylogroups, including those associated with acne (type IA1). We also demonstrate, based on in silico 16S rDNA analysis, that PMH isolates previously recovered from patients in Europe are also consistent with the type III lineage. Using comparative genome analysis, we identified multiple genomic regions that are specific for, or absent from, type III strains compared to other phylogroups. In the former case, these include open reading frames with putative functions in metabolism, transport and transcriptional regulation, as well as predicted proteins of unknown function. Further study of these genomic elements, along with transcriptional and functional analyses, may help to explain why type III strains are associated with PMH. PMID:27555369

  3. Strains of the Propionibacterium acnes type III lineage are associated with the skin condition progressive macular hypomelanosis

    PubMed Central

    Barnard, Emma; Liu, Jared; Yankova, Eliza; Cavalcanti, Silvana M.; Magalhães, Marcelo; Li, Huiying; Patrick, Sheila; McDowell, Andrew

    2016-01-01

    Progressive macular hypomelanosis (PMH) is a common skin disorder that causes hypopigmentation in a variety of skin types. Although the underlying aetiology of this condition is unclear, there is circumstantial evidence that links the skin bacterium Propionibacterium acnes to the condition. We now describe the first detailed population genetic analysis of P. acnes isolates recovered from paired lesional and non-lesional skin of PMH patients. Our results demonstrate a strong statistical association between strains from the type III phylogenetic lineage and PMH lesions (P = 0.0019), but not those representing other phylogroups, including those associated with acne (type IA1). We also demonstrate, based on in silico 16S rDNA analysis, that PMH isolates previously recovered from patients in Europe are also consistent with the type III lineage. Using comparative genome analysis, we identified multiple genomic regions that are specific for, or absent from, type III strains compared to other phylogroups. In the former case, these include open reading frames with putative functions in metabolism, transport and transcriptional regulation, as well as predicted proteins of unknown function. Further study of these genomic elements, along with transcriptional and functional analyses, may help to explain why type III strains are associated with PMH. PMID:27555369

  4. Understanding the sequential activation of Type III and Type VI Secretion Systems in Salmonella typhimurium using Boolean modeling

    PubMed Central

    2013-01-01

    Background Three pathogenicity islands, viz. SPI-1 (Salmonella pathogenicity island 1), SPI-2 (Salmonella pathogenicity island 2) and T6SS (Type VI Secretion System), present in the genome of Salmonella typhimurium have been implicated in the virulence of the pathogen. While the regulation of SPI-1 and SPI-2 (both encoding components of the Type III Secretion System - T3SS) are well understood, T6SS regulation is comparatively less studied. Interestingly, inter-connections among the regulatory elements of these three virulence determinants have also been suggested to be essential for successful infection. However, till date, an integrated view of gene regulation involving the regulators of these three secretion systems and their cross-talk is not available. Results In the current study, relevant regulatory information available from literature have been integrated into a single Boolean network, which portrays the dynamics of T3SS (SPI-1 and SPI-2) and T6SS mediated virulence. Some additional regulatory interactions involving a two-component system response regulator YfhA have also been predicted and included in the Boolean network. These predictions are aimed at deciphering the effects of osmolarity on T6SS regulation, an aspect that has been suggested in earlier studies, but the mechanism of which was hitherto unknown. Simulation of the regulatory network was able to recreate in silico the experimentally observed sequential activation of SPI-1, SPI-2 and T6SS. Conclusions The present study integrates relevant gene regulatory data (from literature and our prediction) into a single network, representing the cross-communication between T3SS (SPI-1 and SPI-2) and T6SS. This holistic view of regulatory interactions is expected to improve the current understanding of pathogenesis of S. typhimurium. PMID:24079299

  5. High frequency of W1327X mutation in glycogen storage disease type III patients from central Tunisia.

    PubMed

    Cherif, Wafa; Ben Rhouma, Faten; Messai, Habib; Mili, Amira; Gribaa, Moez; Kefi, Rym; Ayadi, Abdelkarim; Boughamoura, Lamia; Chemli, Jelel; Saad, Ali; Kaabachi, Naziha; Sfar, Mohamed Tahar; Ben Dridi, Marie-Françoise; Tebib, Neji; Abdelhak, Sonia

    2012-01-01

    Glycogen storage disease type III (GSD III) is an autosomal recessive disorder caused by the deficiency of glycogen debranching enzyme (AGL). It is characterized by hepatomegaly, progressive myopathy, cardiomyopathy and fasting hypoglycemia. Several mutations in AGL gene have been described in different populations. The W1327X mutation was reported in one Tunisian patient resident in Italy. We looked in this report to determine the frequency of W1327X mutation among Tunisian patients. The W1327X mutation was screening in 26 GSD III patients originated from various geographic locations in Tunisia. The sequence analysis revealed that among nine patients carried the W1327X mutation. Eight of them were from six unrelated families and they were originated from Mahdia (centre of Tunisia) suggesting the existence of a founder effect in this region. Taking into account historical migratory waves, screening for this mutation should be performed in priority for molecular diagnosis confirmation of GSD III in North African populations.

  6. Performance of a Single Assay for Both Type III and Type VI TMPRSS2:ERG Fusions in Noninvasive Prediction of Prostate Biopsy Outcome

    PubMed Central

    Clark, Jarrod P.; Munson, Kristofer W.; Gu, Jessie W.; Lamparska-Kupsik, Katarzyna; Chan, Kevin G.; Yoshida, Jeffrey S.; Kawachi, Mark H.; Crocitto, Laura E.; Wilson, Timothy G.; Feng, Ziding; Smith, Steven S.

    2010-01-01

    BACKGROUND TMPRSS2:ERG fusions are promising prostate cancer biomarkers. Because they can occur in multiple forms in a single cancer specimen, we developed a quantitative PCR test that detects both type III and type VI TMPRSS2:ERG fusions. The assay is quantified from a standard curve determined with a plasmid-cloned type III TMPRSS2:ERG fusion target. METHODS We collected expressed prostatic secretion (EPS) under an institutional review board–approved, blinded, prospective study from 74 patients undergoing transrectal ultrasound-guided biopsy for prostate cancer. We compared the characteristic performance of the test for type III and type VI TMPRSS2:ERG fusions in predicting biopsy outcome and distinguishing between high and low Gleason scores with similar tests for the expression of PCA3 and DNA methylation levels of the APC, RARB, RASSF1, and GSTP1 genes. We used logistic regression to analyze the effects of multiple biomarkers in linear combinations. RESULTS Each test provided a significant improvement in characteristic performance over baseline digital rectal examination (DRE) plus serum prostate-specific antigen (PSA); however, the test for type III and type VI TMPRSS2:ERG fusions yielded the best performance in predicting biopsy outcome [area under the curve (AUC) 0.823, 95% CI 0.728–0.919, P < 0.001] and Gleason grade >7 (AUC 0.844, 95% CI 0.740–0.948, P < 0.001). CONCLUSIONS Although each test appears to have diagnostic value, PSA plus DRE plus type III and type VI TMPRSS2:ERG provided the best diagnostic performance in EPS specimens. PMID:18948370

  7. Differential localization of type I and type III procollagen messenger ribonucleic acids in inflamed periodontal and periapical connective tissues by in situ hybridization.

    PubMed

    Larjava, H; Sandberg, M; Happonen, R P; Vuorio, E

    1990-01-01

    Inflammatory lesions of periodontal and periapical connective tissue were studied by in situ hybridization to detect cells responsible for type I and type III collagen production. Formalin-fixed and paraffin-embedded tissue specimens from patients with oral lesions of various stages of inflammation were hybridized with cDNA probes specific for human pro alpha 1(I) and pro alpha 1(III) collagen mRNAs, and with bacteriophage lambda DNA as a control probe. This technique permitted us to localize fibroblasts active in type I collagen synthesis in the vicinity of inflammatory infiltrates in all the samples studied. Cells containing high levels of type III collagen mRNA were seen in early abscess formation and they were particularly abundant in pyogenic granuloma and irritation fibroma. Type I collagen mRNA was prominent in gingival fibrosis. In the infrabony lesions with active inflammatory infiltrations the production of collagen was confined mostly to the periphery of the lesions. These findings give indirect evidence that cytokines liberated during the early stages of the inflammatory process stimulate expression of the type III collagen gene by fibroblasts. In chronic lesions a gradual switch from type III to type I collagen gene expression occurs. The change in collagen types appears to underlie the observed isolation of the inflammation by a collagenous capsule. In all the samples studied fibroblasts exhibited marked variation in their levels of procollagen mRNAs, supporting previous views about their heterogeneity in connective tissues. The approach presented here offers new possibilities to study cellular interactions and metabolic activities in inflammatory lesions. PMID:2296161

  8. Lysogeny with Shiga toxin 2-encoding bacteriophages represses type III secretion in enterohemorrhagic Escherichia coli.

    PubMed

    Xu, Xuefang; McAteer, Sean P; Tree, Jai J; Shaw, Darren J; Wolfson, Eliza B K; Beatson, Scott A; Roe, Andrew J; Allison, Lesley J; Chase-Topping, Margo E; Mahajan, Arvind; Tozzoli, Rosangela; Woolhouse, Mark E J; Morabito, Stefano; Gally, David L

    2012-01-01

    Lytic or lysogenic infections by bacteriophages drive the evolution of enteric bacteria. Enterohemorrhagic Escherichia coli (EHEC) have recently emerged as a significant zoonotic infection of humans with the main serotypes carried by ruminants. Typical EHEC strains are defined by the expression of a type III secretion (T3S) system, the production of Shiga toxins (Stx) and association with specific clinical symptoms. The genes for Stx are present on lambdoid bacteriophages integrated into the E. coli genome. Phage type (PT) 21/28 is the most prevalent strain type linked with human EHEC infections in the United Kingdom and is more likely to be associated with cattle shedding high levels of the organism than PT32 strains. In this study we have demonstrated that the majority (90%) of PT 21/28 strains contain both Stx2 and Stx2c phages, irrespective of source. This is in contrast to PT 32 strains for which only a minority of strains contain both Stx2 and 2c phages (28%). PT21/28 strains had a lower median level of T3S compared to PT32 strains and so the relationship between Stx phage lysogeny and T3S was investigated. Deletion of Stx2 phages from EHEC strains increased the level of T3S whereas lysogeny decreased T3S. This regulation was confirmed in an E. coli K12 background transduced with a marked Stx2 phage followed by measurement of a T3S reporter controlled by induced levels of the LEE-encoded regulator (Ler). The presence of an integrated Stx2 phage was shown to repress Ler induction of LEE1 and this regulation involved the CII phage regulator. This repression could be relieved by ectopic expression of a cognate CI regulator. A model is proposed in which Stx2-encoding bacteriophages regulate T3S to co-ordinate epithelial cell colonisation that is promoted by Stx and secreted effector proteins. PMID:22615557

  9. Lysogeny with Shiga Toxin 2-Encoding Bacteriophages Represses Type III Secretion in Enterohemorrhagic Escherichia coli

    PubMed Central

    Xu, Xuefang; McAteer, Sean P.; Tree, Jai J.; Shaw, Darren J.; Wolfson, Eliza B. K.; Beatson, Scott A.; Roe, Andrew J.; Allison, Lesley J.; Chase-Topping, Margo E.; Mahajan, Arvind; Tozzoli, Rosangela; Woolhouse, Mark E. J.; Morabito, Stefano; Gally, David L.

    2012-01-01

    Lytic or lysogenic infections by bacteriophages drive the evolution of enteric bacteria. Enterohemorrhagic Escherichia coli (EHEC) have recently emerged as a significant zoonotic infection of humans with the main serotypes carried by ruminants. Typical EHEC strains are defined by the expression of a type III secretion (T3S) system, the production of Shiga toxins (Stx) and association with specific clinical symptoms. The genes for Stx are present on lambdoid bacteriophages integrated into the E. coli genome. Phage type (PT) 21/28 is the most prevalent strain type linked with human EHEC infections in the United Kingdom and is more likely to be associated with cattle shedding high levels of the organism than PT32 strains. In this study we have demonstrated that the majority (90%) of PT 21/28 strains contain both Stx2 and Stx2c phages, irrespective of source. This is in contrast to PT 32 strains for which only a minority of strains contain both Stx2 and 2c phages (28%). PT21/28 strains had a lower median level of T3S compared to PT32 strains and so the relationship between Stx phage lysogeny and T3S was investigated. Deletion of Stx2 phages from EHEC strains increased the level of T3S whereas lysogeny decreased T3S. This regulation was confirmed in an E. coli K12 background transduced with a marked Stx2 phage followed by measurement of a T3S reporter controlled by induced levels of the LEE-encoded regulator (Ler). The presence of an integrated Stx2 phage was shown to repress Ler induction of LEE1 and this regulation involved the CII phage regulator. This repression could be relieved by ectopic expression of a cognate CI regulator. A model is proposed in which Stx2-encoding bacteriophages regulate T3S to co-ordinate epithelial cell colonisation that is promoted by Stx and secreted effector proteins. PMID:22615557

  10. Lysogeny with Shiga toxin 2-encoding bacteriophages represses type III secretion in enterohemorrhagic Escherichia coli.

    PubMed

    Xu, Xuefang; McAteer, Sean P; Tree, Jai J; Shaw, Darren J; Wolfson, Eliza B K; Beatson, Scott A; Roe, Andrew J; Allison, Lesley J; Chase-Topping, Margo E; Mahajan, Arvind; Tozzoli, Rosangela; Woolhouse, Mark E J; Morabito, Stefano; Gally, David L

    2012-01-01

    Lytic or lysogenic infections by bacteriophages drive the evolution of enteric bacteria. Enterohemorrhagic Escherichia coli (EHEC) have recently emerged as a significant zoonotic infection of humans with the main serotypes carried by ruminants. Typical EHEC strains are defined by the expression of a type III secretion (T3S) system, the production of Shiga toxins (Stx) and association with specific clinical symptoms. The genes for Stx are present on lambdoid bacteriophages integrated into the E. coli genome. Phage type (PT) 21/28 is the most prevalent strain type linked with human EHEC infections in the United Kingdom and is more likely to be associated with cattle shedding high levels of the organism than PT32 strains. In this study we have demonstrated that the majority (90%) of PT 21/28 strains contain both Stx2 and Stx2c phages, irrespective of source. This is in contrast to PT 32 strains for which only a minority of strains contain both Stx2 and 2c phages (28%). PT21/28 strains had a lower median level of T3S compared to PT32 strains and so the relationship between Stx phage lysogeny and T3S was investigated. Deletion of Stx2 phages from EHEC strains increased the level of T3S whereas lysogeny decreased T3S. This regulation was confirmed in an E. coli K12 background transduced with a marked Stx2 phage followed by measurement of a T3S reporter controlled by induced levels of the LEE-encoded regulator (Ler). The presence of an integrated Stx2 phage was shown to repress Ler induction of LEE1 and this regulation involved the CII phage regulator. This repression could be relieved by ectopic expression of a cognate CI regulator. A model is proposed in which Stx2-encoding bacteriophages regulate T3S to co-ordinate epithelial cell colonisation that is promoted by Stx and secreted effector proteins.

  11. Type III collagen regulates osteoblastogenesis and the quantity of trabecular bone.

    PubMed

    Volk, Susan W; Shah, Shalin R; Cohen, Arthur J; Wang, Yanjian; Brisson, Becky K; Vogel, Laurie K; Hankenson, Kurt D; Adams, Sherrill L

    2014-06-01

    Type III collagen (Col3), a fibril-forming collagen, is a major extracellular matrix component in a variety of internal organs and skin. It is also expressed at high levels during embryonic skeletal development and is expressed by osteoblasts in mature bone. Loss of function mutations in the gene encoding Col3 (Col3a1) are associated with vascular Ehlers-Danlos syndrome (EDS). Although the most significant clinical consequences of this syndrome are associated with catastrophic failure and impaired healing of soft tissues, several studies have documented skeletal abnormalities in vascular EDS patients. However, there are no reports of the role of Col3 deficiency on the murine skeleton. We compared craniofacial and skeletal phenotypes in young (6-8 weeks) and middle-aged (>1 year) control (Col3(+/+)) and haploinsufficient (Col3(+/-)) mice, as well as young null (Col3(-/-)) mice by microcomputed tomography (μCT). Although Col3(+/-) mice did not have significant craniofacial abnormalities based upon cranial morphometrics, μCT analysis of distal femur trabecular bone demonstrated significant reductions in bone volume (BV), bone volume fraction (BV/TV), connectivity density, structure model index and trabecular thickness in young adult female Col3(+/-) mice relative to wild-type littermates. The reduction in BV/TV persisted in female mice at 1 year of age. Next, we evaluated the role of Col3 in vitro. Osteogenesis assays revealed that cultures of mesenchymal progenitors collected from Col3(-/-) embryos display decreased alkaline phosphatase activity and reduced capacity to undergo mineralization. Consistent with this data, a reduction in expression of osteogenic markers (type I collagen, osteocalcin and bone sialoprotein) correlates with reduced bone Col3 expression in Col3(+/-) mice and with age in vivo. A small but significant reduction in osteoclast numbers was found in Col3(+/-) compared to Col3(+/+) bones. Taken together, these findings indicate that Col3 plays a

  12. Temporomandibular joint internal derangement type III: relationship to magnetic resonance imaging findings of internal derangement and osteoarthrosis. An intraindividual approach.

    PubMed

    Emshoff, R; Rudisch, A; Innerhofer, K; Bösch, R; Bertram, S

    2001-10-01

    The purpose of this study was to investigate whether in patients with a clinical unilateral temporomandibular joint (TMJ)-related finding of internal derangement type (ID)-III (disk displacement without reduction) in combination with TMJ-related pain, the intraindividual variable of 'unilateral TMJ ID-III pain' may be linked to subject-related magnetic resonance (MR) imaging findings of TMJ ID, and TMJ osteoarthrosis (OA). The study comprised 48 consecutive TMJ pain patients, who were assigned a clinical unilateral TMJ pain side-related diagnosis of ID-III. Bilateral sagittal and coronal MR images were obtained to establish the presence or absence of TMJ ID and/or OA. Comparison of the TMJ side-related data showed a significant relationship between the clinical finding of TMJ ID-III pain and the MR imaging diagnoses of TMJ ID (P=0.000) and TMJ ID type (P=0.000). There was no correlation between the clinical finding of TMJ ID-III pain and the MR imaging diagnosis of TMJ OA (P=0.217), nor between the MR imaging diagnosis of TMJ OA and that of TMJ ID (P=0.350). Regarding the diagnostic subgroups of TMJ ID, a significant relationship was found between the presence of TMJ OA and the MR imaging diagnoses of TMJ ID type(P=0.002). Use of the Kappa statistical test indicated a fair diagnostic agreement between the presence of TMJ ID-III pain and the MR imaging diagnosis of disk displacement without reduction (DDNR) (K=0.42). The results suggest that TMJ ID-III pain is related to TMJ-related MR imaging diagnoses of ID. Further, the data confirm the biological concept of 'DDNR and OA' as an underlying mechanism in the etiology of TMJ-related pain and dysfunction. PMID:11720040

  13. Expression patterns of collagen types I and III in the capsule of a rat knee contracture model.

    PubMed

    Hagiwara, Yoshihiro; Ando, Akira; Onoda, Yoshito; Matsui, Hiroyuki; Chimoto, Eiichi; Suda, Hideaki; Itoi, Eiji

    2010-03-01

    Our objective was to determine the changes in expression of collagen types I and III in the capsule of a rat knee contracture model. The unilateral knee joints of adult male rats were rigidly immobilized at 150 degrees of flexion using a rigid plastic plate and screws for 3 days, 1, 2, 4, 8, and 16 weeks (immobilized group). Sham-operated animals had holes drilled in the femur and tibia with screws inserted without a plate (control group). The expression patterns of collagen types I and III in the anterior and posterior capsule were evaluated by in situ hybridization (ISH), quantitative real-time polymerase chain reaction (qPCR), immunohistochemistry (IHC), and Western blotting (WB). Expressions of collagen types I and III were decreased after immobilization compared to the control group by ISH and qPCR. The expression was not changed after immobilization compared to the control group by IHC and WB. The expression of mRNA and protein levels of collagen types I and III were not increased after immobilization, which indicated that accumulation of the two types of collagen was not the etiology of joint contracture. Another process, such as capsule and synovial adhesions, may be one possible cause of joint contracture.

  14. A modeling study of notch noise responses of type III units in the gerbil dorsal cochlear nucleus.

    PubMed

    Zheng, Xiaohan; Voigt, Herbert F

    2006-12-01

    A computational model of the neural circuitry of the gerbil dorsal cochlear nucleus (DCN), based on the MacGregor's neuromime model, was used to simulate type III unit (P-cell) responses to notch noise stimuli. The DCN patch model is based on a previous computational model of the cat DCN [Hancock, K. E., and H. F. Voigt. Ann. Biomed. Eng. 27:73-87, 1999]. According to the experimental study of Parsons et al. [Ann. Biomed. Eng. 29:887-896, 2001], the responses of gerbil DCN type III units to notch noise stimuli are similar to those of cat DCN type IV units, which are thought to be spectral notch detectors. This suggests that type III units in the gerbil DCN may serve as spectral notch detectors. In this modeling study, a simplified notch noise response plot--spike discharge rate vs. notch cutoff frequency plot--was used to compare model responses to the experimental results. Parameter estimation and sensitivity analysis of three connection parameters within the DCN patch have been studied and shows the model is robust, providing reasonable fits to the experimental data from 14 of 15 type III units examined.

  15. Correlating Type II and III Radio Bursts with Solar Energetic Particle Events

    NASA Astrophysics Data System (ADS)

    Ledbetter, K.; Winter, L. M.; Quinn, R. A.

    2013-12-01

    Solar energetic particles (SEPs) are high-energy particles, such as protons, which are accelerated at the Sun and speed outward into the solar system. If they reach Earth, they can be harmful to satellites, ionospheric communications, and humans in space or on polar airline routes. NOAA defines an SEP event as an occasion when the flux of protons with energies higher than 10 MeV exceeds 10 pfu (particle flux units) as measured by the GOES satellites in geosynchronous orbit. The most intense SEP events are associated with shocks, driven by coronal mass ejections (CMEs), which accelerate particles as they move through the corona. However, very few CMEs result in SEP events. To determine what factors are most important in distinguishing the shock waves that will result in SEP acceleration toward Earth, we take into account several variables and perform a principal component analysis (PCA) to examine their correlations. First, we examine Type II radio bursts, which are caused by electrons accelerating in the same CME-driven shocks that can accelerate SEPs. Using data from the WAVES instrument on the WIND satellite, these Type II radio bursts, as well as the Type III bursts that often accompany them, can be characterized by slope in 1/f space and by intensity. In addition, local Langmuir waves detected by WIND, which are caused by electrons speeding through the plasma surrounding the satellite, can be an indicator of the magnetic connectivity between the active region and Earth. Finally, X-ray flares directly preceding the Type II burst are also taken into consideration in the PCA analysis. The accompanying figure illustrates an example of the WAVES solar radio bursts along with the GOES solar proton flux >= 10 MeV during the SEP event on April 11, 2013. Using PCA to determine which of these factors are most relevant to the onset, intensity, and duration of SEP events will be valuable in future work to predict such events. In total, we present the analysis of all type

  16. A Decade of Solar Type III Radio Bursts Observed by the Nancay Radioheliograph 1998-2008

    NASA Astrophysics Data System (ADS)

    Saint-Hilaire, Pascal; Vilmer, N.; Kerdraon, A.

    2013-07-01

    We present a statistical survey of almost 10'000 radio type III bursts observed by the Nancay Radioheliograph from 1998 to 2008, covering nearly a full solar cycle. In particular, sources sizes, positions, and fluxes were examined. We find an east-west asymmetry in source positions that could be attributed to a ~6 degrees eastward tilt of the magnetic field, that source FWHM sizes s roughly follow a solar-cycle-averaged distribution dN/ds = 14 ν-3.3s-4 arcmin-1 day-1, and that source fluxes closely follow a solar-cycle-averaged dN/dS = 0.34 ν-2.9 S-1.7 sfu-1 day-1 distribution (when ν is in GHz, s in arcminutes, and S in sfu). Fitting a barometric density profile yields a temperature of 0.6 MK, while a solar wind-like h-2) density profile yields a density of 1.2 × 106 cm-3 at an altitude of 1 Rs, assuming harmonic emission. Finally, the flux distribution combined with rough radiative efficiency estimates hint at the possibility that escaping electron beams might carry as much energy away from the corona as is introduced into it by nanoflare-accelerated electrons.

  17. Serum type III procollagen N-terminal peptide in coal miners

    SciTech Connect

    Janssen, Y.M.; Engelen, J.J.; Giancola, M.S.; Low, R.B.; Vacek, P.; Borm, P.J. )

    1992-01-01

    Health surveillance of workers exposed to fibrogenic agents ideally should identify individuals at risk or detect pulmonary fibrosis in preclinical stages. We investigated serum procollagen type III N-terminal peptide (PIIIP) in several groups of active miners and in a nondust-exposed control group. The purpose of this study was to determine the applicability of PIIIP as an early noninvasive marker of pulmonary fibrosis in workers exposed to coal mine dust. PIIIP levels were significantly elevated in miners without radiological signs of coal workers pneumoconiosis (CWP) as compared with the nonexposed controls. However, in coal miners with CWP beyond ILO classification 1/0, PIIIP levels were not significantly different from nondust-exposed controls. Trend analysis within the miners group indicated a decrease in PIIIP levels with progression of the fibrosis. Our data suggest that detection of early lung fibrosis by measuring serum PIIIP values may be more sensitive than radiological diagnosis of CWP. However, follow-up of the control miners with respect to serum PIIIP and chest radiography is essential to validate PIIIP as a biological marker for CWP.

  18. The structural and optical properties of type III human collagen biosynthetic corneal substitutes

    PubMed Central

    Hayes, Sally; Lewis, Phillip; Islam, M. Mirazul; Doutch, James; Sorensen, Thomas; White, Tomas; Griffith, May; Meek, Keith M.

    2015-01-01

    The structural and optical properties of clinically biocompatible, cell-free hydrogels comprised of synthetically cross-linked and moulded recombinant human collagen type III (RHCIII) with and without the incorporation of 2-methacryloyloxyethyl phosphorylcholine (MPC) were assessed using transmission electron microscopy (TEM), X-ray scattering, spectroscopy and refractometry. These findings were examined alongside similarly obtained data from 21 human donor corneas. TEM demonstrated the presence of loosely bundled aggregates of fine collagen filaments within both RHCIII and RHCIII-MPC implants, which X-ray scattering showed to lack D-banding and be preferentially aligned in a uniaxial orientation throughout. This arrangement differs from the predominantly biaxial alignment of collagen fibrils that exists in the human cornea. By virtue of their high water content (90%), very fine collagen filaments (2–9 nm) and lack of cells, the collagen hydrogels were found to transmit almost all incident light in the visible spectrum. They also transmitted a large proportion of UV light compared to the cornea which acts as an effective UV filter. Patients implanted with these hydrogels should be cautious about UV exposure prior to regrowth of the epithelium and in-growth of corneal cells into the implants. PMID:26159106

  19. Pseudomonas syringae type III effector AvrRpt2 alters Arabidopsis thaliana auxin physiology

    PubMed Central

    Chen, Zhongying; Agnew, Jennifer L.; Cohen, Jerry D.; He, Ping; Shan, Libo; Sheen, Jen; Kunkel, Barbara N.

    2007-01-01

    The Pseudomonas syringae type III effector AvrRpt2 promotes bacterial virulence on Arabidopsis thaliana plants lacking a functional RPS2 gene (rps2 mutant plants). To investigate the mechanisms underlying the virulence activity of AvrRpt2, we examined the phenotypes of transgenic A. thaliana rps2 seedlings constitutively expressing AvrRpt2. These seedlings exhibited phenotypes reminiscent of A. thaliana mutants with altered auxin physiology, including longer primary roots, increased number of lateral roots, and increased sensitivity to exogenous auxin. They also had increased levels of free indole acetic acid (IAA). The presence of AvrRpt2 also was correlated with a further increase in free IAA levels during infection with P. syringae pv. tomato strain DC3000 (PstDC3000). These results indicate that AvrRpt2 alters A. thaliana auxin physiology. Application of the auxin analog 1-naphthaleneacetic acid promoted disease symptom development in PstDC3000-infected plants, suggesting that elevated auxin levels within host tissue promote PstDC3000 virulence. Thus, AvrRpt2 may be among the virulence factors of P. syringae that modulate host auxin physiology to promote disease. PMID:18056646

  20. Modulation of innate immune responses by Yersinia type III secretion system translocators and effectors

    PubMed Central

    Bliska, James B.; Wang, Xiaoying; Viboud, Gloria I.; Brodsky, Igor E.

    2013-01-01

    Summary The innate immune system of mammals responds to microbial infection through detection of conserved molecular determinants called “pathogen-associated molecular patterns” (PAMPs). Pathogens use virulence factors to counteract PAMP-directed responses. The innate immune system can in turn recognize signals generated by virulence factors, allowing for a heightened response to dangerous pathogens. Many Gram-negative bacterial pathogens encode type III secretion systems (T3SSs) that translocate effector proteins, subvert PAMP-directed responses and are critical for infection. A plasmid-encoded T3SS in the human-pathogenic Yersinia species translocates seven effectors into infected host cells. Delivery of effectors by the T3SS requires plasma membrane insertion of two translocators, which are thought to form a channel called a translocon. Studies of the Yersinia T3SS have provided key advances in our understanding of how innate immune responses are generated by perturbations in plasma membrane and other signals that result from translocon insertion. Additionally, studies in this system revealed that effectors function to inhibit innate immune responses resulting from insertion of translocons into plasma membrane. Here, we review these advances with the goal of providing insight into how a T3SS can activate and inhibit innate immune responses, allowing a virulent pathogen to bypass host defenses. PMID:23834311

  1. Type III Interferons Produced by Human Placental Trophoblasts Confer Protection against Zika Virus Infection.

    PubMed

    Bayer, Avraham; Lennemann, Nicholas J; Ouyang, Yingshi; Bramley, John C; Morosky, Stefanie; Marques, Ernesto Torres De Azeved; Cherry, Sara; Sadovsky, Yoel; Coyne, Carolyn B

    2016-05-11

    During mammalian pregnancy, the placenta acts as a barrier between the maternal and fetal compartments. The recently observed association between Zika virus (ZIKV) infection during human pregnancy and fetal microcephaly and other anomalies suggests that ZIKV may bypass the placenta to reach the fetus. This led us to investigate ZIKV infection of primary human trophoblasts (PHTs), which are the barrier cells of the placenta. We discovered that PHT cells from full-term placentas are refractory to ZIKV infection. In addition, medium from uninfected PHT cells protects non-placental cells from ZIKV infection. PHT cells constitutively release the type III interferon (IFN) IFNλ1, which functions in both a paracrine and autocrine manner to protect trophoblast and non-trophoblast cells from ZIKV infection. Our data suggest that for ZIKV to access the fetal compartment, it must evade restriction by trophoblast-derived IFNλ1 and other trophoblast-specific antiviral factors and/or use alternative strategies to cross the placental barrier. PMID:27066743

  2. Helical packing of needles from functionally altered Shigella type III secretion systems.

    PubMed

    Cordes, Frank S; Daniell, Sarah; Kenjale, Roma; Saurya, Saroj; Picking, Wendy L; Picking, William D; Booy, Frank; Lea, Susan M; Blocker, Ariel

    2005-11-25

    Gram-negative bacteria commonly interact with eukaryotic host cells using type III secretion systems (TTSSs or secretons), which comprise cytoplasmic, transmembrane and extracellular domains. The extracellular domain is a hollow needle-like structure protruding 60 nm beyond the bacterial surface. The TTSS is activated to transfer bacterial proteins directly into a host cell only upon physical contact with the target cell. We showed previously that the monomer of the Shigella flexneri needle, MxiH, assembles into a helical structure with parameters similar to those defining the architecture of the extracellular components of bacterial flagella. By analogy with flagella, which are known to exist in different helical states, we proposed that changes in the helical packing of the needle might be used to sense host cell contact. Here, we show that, on the contrary, mutations within MxiH that lock the TTSS into altered secretion states do not detectably alter the helical packing of needles. This implies that either: (1) host cell contact is signalled through the TTSS via helical changes in the needle that are significantly smaller than those linked to structural changes in the flagellar filament and therefore too small to be detected by our analysis methods or (2) that signal transduction in this system occurs via a novel molecular mechanism. PMID:16243352

  3. Distinct Structural Elements Dictate the Specificity of the Type III Pentaketide Synthase from Neurospora crassa

    SciTech Connect

    Rubin-Pitel, Sheryl B.; Zhang, Houjin; Vu, Trang; Brunzelle, Joseph S.; Zhao, Huimin; Nair, Satish K.

    2009-01-15

    The fungal type III polyketide synthase 2'-oxoalkylresorcyclic acid synthase (ORAS) primes with a range of acyl-Coenzyme A thioesters (C{sub 4}--C{sub 20}) and extends using malonyl-Coenzyme A to produce pyrones, resorcinols, and resorcylic acids. To gain insight into this unusual substrate specificity and product profile, we have determined the crystal structures of ORAS to 1.75 {angstrom} resolution, the Phe-252{yields}Gly site-directed mutant to 2.1 {angstrom} resolution, and a binary conplex of ORAS with eicosanoic acid to 2.0 {angstrom} resolution. The structures reveal a distinct rearrangement of structural elements near the active site that allows accomodation of long-chain fatty acid esters and a reorientation of the gating mechanism that controls cyclization and polyketide chain length. The roles of these structural elements are further elucidated by characterization of various structure-based site-directed variants. These studies establish an unexpected plasticity to the PKS fold, unanticipated from structural studies of other members of this enzyme family.

  4. Variation of Langmuir wave polarization with electron beam speed in type III radio bursts

    SciTech Connect

    Malaspina, David M.; Cairns, Iver H.; Ergun, Robert E.

    2013-06-13

    Observations by the twin STEREO spacecraft of in-situ electric field waveforms and radio signatures associated with type III radio bursts have demonstrated that the polarization of electron beam-driven waves near the local plasma frequency depends strongly on the speed of the driving electron beam. We expand upon a previous study by including all radio bursts with in-situ waveforms observed by STEREO in 2011. The expanded data set contains five times more radio bursts (35 up from 7) and three times as many Langmuir waves (663 up from 168). While this expanded study supports the results of the original study, that faster (slower) beam electrons drive waves with strong (weak) electric fields perpendicular to the local magnetic field, the larger data set emphasizes that the observation of strong perpendicular electric fields at high electron beam speeds is probabilistic rather than definite. This property supports the interpretation of wave polarization dependence on beam speed as Langmuir/z-mode waves shifted to small wave number through interaction with turbulent solar wind density fluctuations.

  5. Evaluation of Salmonella enterica type III secretion system effector proteins as carriers for heterologous vaccine antigens.

    PubMed

    Hegazy, Wael Abdel Halim; Xu, Xin; Metelitsa, Leonid; Hensel, Michael

    2012-03-01

    Live attenuated strains of Salmonella enterica have a high potential as carriers of recombinant vaccines. The type III secretion system (T3SS)-dependent translocation of S. enterica can be deployed for delivery of heterologous antigens to antigen-presenting cells. Here we investigated the efficacy of various effector proteins of the Salmonella pathogenicity island (SPI2)-encoded T3SS for the translocation of model antigens and elicitation of immune responses. The SPI2 T3SS effector proteins SifA, SteC, SseL, SseJ, and SseF share an endosomal membrane-associated subcellular localization after translocation. We observed that all effector proteins could be used to translocate fusion proteins with the model antigens ovalbumin and listeriolysin into the cytosol of host cells. Under in vitro conditions, fusion proteins with SseJ and SteC stimulated T-cell responses that were superior to those triggered by fusion proteins with SseF. However, in mice vaccinated with Salmonella carrier strains, only fusion proteins based on SseJ or SifA elicited potent T-cell responses. These data demonstrate that the selection of an optimal SPI2 effector protein for T3SS-mediated translocation is a critical parameter for the rational design of effective Salmonella-based recombinant vaccines.

  6. Bile salt receptor complex activates a pathogenic type III secretion system.

    PubMed

    Li, Peng; Rivera-Cancel, Giomar; Kinch, Lisa N; Salomon, Dor; Tomchick, Diana R; Grishin, Nick V; Orth, Kim

    2016-01-01

    Bile is an important component of the human gastrointestinal tract with an essential role in food absorption and antimicrobial activities. Enteric bacterial pathogens have developed strategies to sense bile as an environmental cue to regulate virulence genes during infection. We discovered that Vibrio parahaemolyticus VtrC, along with VtrA and VtrB, are required for activating the virulence type III secretion system 2 in response to bile salts. The VtrA/VtrC complex activates VtrB in the presence of bile salts. The crystal structure of the periplasmic domains of the VtrA/VtrC heterodimer reveals a β-barrel with a hydrophobic inner chamber. A co-crystal structure of VtrA/VtrC with bile salt, along with biophysical and mutational analysis, demonstrates that the hydrophobic chamber binds bile salts and activates the virulence network. As part of a family of conserved signaling receptors, VtrA/VtrC provides structural and functional insights into the evolutionarily conserved mechanism used by bacteria to sense their environment. PMID:27377244

  7. The structural and optical properties of type III human collagen biosynthetic corneal substitutes.

    PubMed

    Hayes, Sally; Lewis, Phillip; Islam, M Mirazul; Doutch, James; Sorensen, Thomas; White, Tomas; Griffith, May; Meek, Keith M

    2015-10-01

    The structural and optical properties of clinically biocompatible, cell-free hydrogels comprised of synthetically cross-linked and moulded recombinant human collagen type III (RHCIII) with and without the incorporation of 2-methacryloyloxyethyl phosphorylcholine (MPC) were assessed using transmission electron microscopy (TEM), X-ray scattering, spectroscopy and refractometry. These findings were examined alongside similarly obtained data from 21 human donor corneas. TEM demonstrated the presence of loosely bundled aggregates of fine collagen filaments within both RHCIII and RHCIII-MPC implants, which X-ray scattering showed to lack D-banding and be preferentially aligned in a uniaxial orientation throughout. This arrangement differs from the predominantly biaxial alignment of collagen fibrils that exists in the human cornea. By virtue of their high water content (90%), very fine collagen filaments (2-9 nm) and lack of cells, the collagen hydrogels were found to transmit almost all incident light in the visible spectrum. They also transmitted a large proportion of UV light compared to the cornea which acts as an effective UV filter. Patients implanted with these hydrogels should be cautious about UV exposure prior to regrowth of the epithelium and in-growth of corneal cells into the implants. PMID:26159106

  8. [Recurrent tracheoesophageal fistula in type III esophageal atresia. Diagnosis and treatment are not easy].

    PubMed

    Lepeytre, C; Roquelaure, B; de Lagausie, P; Merrot, T; Dubus, J-C

    2014-07-01

    Recurrent tracheoesophageal fistula (TEF) is possible after repair of congenital esophageal atresia. The frequency of recurrent TEF is observed in about 10% of the cases. Within a cohort of 67 children with type III esophageal atresia repaired between 1998 and 2009, we aimed to identify the number of children with recurrent TEF, the risk factors for this condition, and the treatment proposed. The sex ratio was 1.7. Surgery was performed between 4 and 36 hours of life. Five children (7.5%) had a recurrent TEF, usually during the first 3 months, revealed by respiratory symptoms related to feeding in some cases. We noted that recurrent TEF was more frequent with anastomotic leakage (P=0.09) or postsurgical pneumothorax (P<0.01). The diagnosis was made in four cases out of five by a methylene blue test performed during a tracheobronchial endoscopy. Surgical treatment was noted in four children, with three postsurgical secondary effects. One child was treated by endoscopy and an esophageal clip. With a median follow-up of 52 months, no recurrence was noted. The recurrence of TEF may be linked to postsurgical events. Diagnosis is not easy and treatment is not clearly codified. Endoscopic treatment may be an advantageous option to surgery, likely with less morbidity.

  9. Bacterial type III secretion systems: specialized nanomachines for protein delivery into target cells.

    PubMed

    Galán, Jorge E; Lara-Tejero, Maria; Marlovits, Thomas C; Wagner, Samuel

    2014-01-01

    One of the most exciting developments in the field of bacterial pathogenesis in recent years is the discovery that many pathogens utilize complex nanomachines to deliver bacterially encoded effector proteins into target eukaryotic cells. These effector proteins modulate a variety of cellular functions for the pathogen's benefit. One of these protein-delivery machines is the type III secretion system (T3SS). T3SSs are widespread in nature and are encoded not only by bacteria pathogenic to vertebrates or plants but also by bacteria that are symbiotic to plants or insects. A central component of T3SSs is the needle complex, a supramolecular structure that mediates the passage of the secreted proteins across the bacterial envelope. Working in conjunction with several cytoplasmic components, the needle complex engages specific substrates in sequential order, moves them across the bacterial envelope, and ultimately delivers them into eukaryotic cells. The central role of T3SSs in pathogenesis makes them great targets for novel antimicrobial strategies.

  10. Bile salt receptor complex activates a pathogenic type III secretion system

    PubMed Central

    Li, Peng; Rivera-Cancel, Giomar; Kinch, Lisa N; Salomon, Dor; Tomchick, Diana R; Grishin, Nick V; Orth, Kim

    2016-01-01

    Bile is an important component of the human gastrointestinal tract with an essential role in food absorption and antimicrobial activities. Enteric bacterial pathogens have developed strategies to sense bile as an environmental cue to regulate virulence genes during infection. We discovered that Vibrio parahaemolyticus VtrC, along with VtrA and VtrB, are required for activating the virulence type III secretion system 2 in response to bile salts. The VtrA/VtrC complex activates VtrB in the presence of bile salts. The crystal structure of the periplasmic domains of the VtrA/VtrC heterodimer reveals a β-barrel with a hydrophobic inner chamber. A co-crystal structure of VtrA/VtrC with bile salt, along with biophysical and mutational analysis, demonstrates that the hydrophobic chamber binds bile salts and activates the virulence network. As part of a family of conserved signaling receptors, VtrA/VtrC provides structural and functional insights into the evolutionarily conserved mechanism used by bacteria to sense their environment. DOI: http://dx.doi.org/10.7554/eLife.15718.001 PMID:27377244

  11. Structure of a bacterial type III secretion system in contact with a host membrane in situ

    PubMed Central

    Nans, Andrea; Kudryashev, Mikhail; Saibil, Helen R.; Hayward, Richard D.

    2015-01-01

    Many bacterial pathogens of animals and plants use a conserved type III secretion system (T3SS) to inject virulence effector proteins directly into eukaryotic cells to subvert host functions. Contact with host membranes is critical for T3SS activation, yet little is known about T3SS architecture in this state or the conformational changes that drive effector translocation. Here we use cryo-electron tomography and sub-tomogram averaging to derive the intact structure of the primordial Chlamydia trachomatis T3SS in the presence and absence of host membrane contact. Comparison of the averaged structures demonstrates a marked compaction of the basal body (4 nm) occurs when the needle tip contacts the host cell membrane. This compaction is coupled to a stabilization of the cytosolic sorting platform–ATPase. Our findings reveal the first structure of a bacterial T3SS from a major human pathogen engaged with a eukaryotic host, and reveal striking ‘pump-action' conformational changes that underpin effector injection. PMID:26656452

  12. Phenolic lipid synthesis by type III polyketide synthases is essential for cyst formation in Azotobacter vinelandii.

    PubMed

    Funa, Nobutaka; Ozawa, Hiroki; Hirata, Aiko; Horinouchi, Sueharu

    2006-04-18

    Cysts of Azotobacter vinelandii are resting cells that are surrounded by a protective coat, conferring resistance to various chemical and physical agents. The major chemical components of the cyst coat are alkylresorcinols, which are amphiphilic molecules possessing an aromatic ring with a long aliphatic carbon chain. Although alkylresorcinols are widely distributed in bacteria, fungi, plants, and animals, no enzyme systems for their biosynthesis are known. We report here an ars operon in A. vinelandii that is responsible for the biosynthesis of the alkylresorcinols in the cysts. The ars operon consisted of four genes, two of which encoded a type III polyketide synthase, ArsB and ArsC. In vitro experiments revealed that ArsB and ArsC, sharing 71% amino acid sequence identity, were an alkylresorcinol synthase and an alkylpyrone synthase, respectively, indicating that ArsB and ArsC are not isozymes but enzymatically distinct polyketide synthases. In addition, ArsB and ArsC accepted several acyl-CoAs with various lengths of the side chain as a starter substrate and gave corresponding alkylresorcinols and alkylpyrones, respectively, which suggests that the mode of the ring folding is uninfluenced by the structure of the starter substrates. The importance of the alkylresorcinols for encystment was confirmed by gene inactivation experiments; the lack of alkylresorcinols synthesis caused by ars mutations resulted in the formation of severely impaired cysts, as observed by electron microscopy.

  13. Type-III seesaw fermionic triplets at high energy e+e- collider

    NASA Astrophysics Data System (ADS)

    Goswami, Deepanjali; Poulose, Poulose

    2016-03-01

    We investigate the signature of heavy fermionic triplets belonging to Type-III seesaw model through their direct production at the high energy e+e- collider. Single and pair production of the charged (Σ+/-) and neutral (Σ0) triplets through the processes, e+e- -->Σ+Σ- ,Σ0Σ0 ,Σ0 ν ,Σ+/- l are considered for the study. The subsequent decay of the triplets to the detector level final states are studied with the corresponding Standard Model (SM) background processes. The decay distributions are considered in details to identify the significant channels, after devising and employing suitable methods to reduce backgrounds and enhance the signal significance. Advantage of single triplet production in association with the charged SM leptons to investigate the mixing of the triplet with the SM leptons is exploited. Preliminary results show the presence of charged fermionic triplets up to a mass of ~ 950 GeV could be established through the single production at 1 TeV ILC, assuming a fermionic triplet electron mixing of 0.05 and a moderate integrated luminosity of 300 fb-1 . Further, constraints in the mass-mixing are obtained for different CM energies assuming different luminosities.

  14. Magnetic Reconnection of Solar Flare Detected by Solar Radio Burst Type III

    NASA Astrophysics Data System (ADS)

    Hamidi, Z. S.; Shariff, N. N. M.; Ibrahim, Z. A.; Monstein, C.; Zulkifli, W. N. A. Wan; Ibrahim, M. B.; Arifin, N. S.; Amran, N. A.

    2014-10-01

    The Sun is an ideal object of a blackbody with a large and complex magnetic field. In solar activity specifically solar flare phenomenon, the magnetic reconnection is one of the most significant factors of the Sun that can simplify a better understanding of our nearest star. This factor is due to the motion of the plasma and other particles through the convection mechanism inside the Sun. In our work, we will highlight one of the solar burst events that associated with solar flares. This event occurred on 13th November 2012 from 2:00:03 UT till 2:00:06 UT. It peaked with M2.0 solar flare at 2.04 UT. Within short time intervals of about l02 ~ 103s, large quantities of energy of 1022 ~ 1026J are emancipated. The changing magnetic field converts magnetic potential energy into kinetic energy by accelerating plasmas in the solar corona. It is believed that the plasma is channelled by the magnetic field up and away from the Sun. It is also accelerated back down along the magnetic field into the chromosphere. In conclusion, we showed that the structure of the solar radio burst type III is an indicator of a starting point of magnetic reconnection.

  15. The speeds of electrons that excite solar radio bursts of type III

    NASA Technical Reports Server (NTRS)

    Dulk, G. A.; Goldman, M. V.; Steinberg, J. L.; Hoang, S.

    1987-01-01

    Evidence is presented that solar type III radio bursts at kilometric wavelengths are excited by electrons with average speeds of 0.14 c; i.e., in good agreement with in situ measurements by Lin et al. (1981; 1986), but considerably lower than the generally accepted values of 0.3 to 0.5 c. A set of 28 bursts for which electrons and/or plasma waves were observed at ISEE-3 is examined, and it is found that the initial parts of all bursts were due to plasma radiation at the fundamental, and that the fastest electrons that produce radio emission range from 0.25 c down to 0.07 c (average 0.14 c). The slower electrons, those that produce fundamental radiation at approximately the time of burst peak, have an average speed of 0.06 c and a range from about 0.10 c down to 0.03 c.There is no evidence in the data for a systematic increase or decrease of exciting electron speed with distance from the sun.

  16. Phase Coupling Between Spectral Components of Collapsing Langmuir Solitons in Solar Type III Radio Bursts

    NASA Technical Reports Server (NTRS)

    Thejappa, G.; MacDowall, R. J.; Bergamo, M.

    2012-01-01

    We present the high time resolution observations of one of the Langmuir wave packets obtained in the source region of a solar type III radio burst. This wave packet satisfies the threshold condition of the supersonic modulational instability, as well as the criterion of a collapsing Langmuir soliton, i.e., the spatial scale derived from its peak intensity is less than that derived from its short time scale. The spectrum of t his wave packet contains an intense spectral peak at local electron plasma frequency, f(sub pe) and relatively weaker peaks at 2f(sub pe) and 3f(sub pe). We apply the wavelet based bispectral analysis technique on this wave packet and compute the bicoherence between its spectral components. It is found that the bicoherence exhibits two peaks at (approximately f(sub pe), approximately f(sub pe)) and (approximately f(sub pe) approximately 2f(sub pe)), which strongly suggest that the spectral peak at 2f(sub pe) probably corresponds to the second harmonic radio emission, generated as a result of the merging of antiparallel propagating Langmuir waves trapped in the collapsing Langmuir soliton, and, the spectral peak at 3f(sub pe) probably corresponds to the third harmonic radio emission, generated as a result of merging of a trapped Langmuir wave and a second harmonic electromagnetic wave.

  17. Current understanding of the physics of type III solar radio bursts

    NASA Technical Reports Server (NTRS)

    Papadopoulos, K.

    1980-01-01

    One of the most exciting plasma physics investigations of recent years has been connected with the understanding of a new strong turbulent plasma state excited by propagating electron beams. This new state is initiated on the linear level by parametric instabilities (OTS, modulational, etc.) and results in a very dynamic state composed of collective clusters of modes called solitons, cavitons, spikons, etc. Introduction of these concepts into the classic beam-plasma interaction problem has rendered quasi-linear and weak turbulence theories inapplicable over most of the interesting parameter range, and helped explain many paradoxes connected with the propagation of beams in the laboratory and space. Following a brief review of these nonlinear notions, the means by which their application to type III solar radiobursts has revolutionized understanding of their propagation, radioemission and scaling properties and has guided the in situ observations towards a more complete understanding are demonstrated. A particular burst (May 16, 1971) is analyzed in detail and compared with numerical predictions.

  18. Energetic electrons and plasma waves associated with a solar type III radio burst

    SciTech Connect

    Lin, R.P.; Potter, D.W.; Gurnett, D.A.; Scarf, F.L.

    1981-12-01

    We present detailed in situ observations from the ISEE 3 spacecraft of energetic electrons, plasma waves, and radio emission for the type III solar radio burst of 1979 February 17. The reduced one-dimensional distribution function f (v) of the electrons is constructed as a function of time. Since the faster electrons arrive before the slower ones, a bump on tail distribution is formed which is unstable on the growth of Langmuir waves. The plasma wave growth computed from f (v) agrees well with the observed onset of the Langmuir waves, and there is qualitative agreement between variations in the plasma wave levels and in the development of regions of positive slope in f (v). The evolution of f (v), however, predicts far higher plasma wave levels than those observed. The maximum levels observed are about equal to the threshold for nonlinear wave processes, such as oscillating two-stream instability and soliton collapse. Also, the lack of obvious plateauing of the distribution suggests that the observed waves have been removed from resonance with the beam electrons. Finally, the plasma waves are observed to be highly impulsive in nature.

  19. Bianchi type-III models with anisotropic dark energy in Brans-Dicke-Rastall theory

    NASA Astrophysics Data System (ADS)

    Salako, Ines G.; Jawad, Abdul

    2015-10-01

    In this paper, we consider the Bianchi type-III metric (which is a spatially homogeneous and anisotropic) in the framework of a newly proposed Brans-Dicke-Rastall theory of gravitation by Caramês et al. (Eur. Phys. J. C 74:3145, 2014. In this scenario, we obtain the generalized form of the anisotropy parameter of the expansion, the dynamically anisotropic equation of state parameter, and a dynamical energy density in the presence of a single diagonal imperfect fluid. By assuming the anisotropy of the fluid, and exponential and power-law volumetric expansions, we find the exact solutions of the Brans-Dicke-Rastall field equations. We examine the isotropy of the fluid, of space, and of the expansion of the universe. It is observed that the universe can approach the isotropy monotonically even in the presence of an anisotropic fluid. We also note that the strong anisotropy observed in RG, respectively, is diminished considerably in the Rastall theory and Brans-Dicke-Rastall theory because of the influence of the parameters and.

  20. Towards the Identification of Type III Effectors Associated with Ralstonia solanacearum Virulence on Tomato and Eggplant.

    PubMed

    Pensec, Flora; Lebeau, Aurore; Daunay, M C; Chiroleu, Frédéric; Guidot, Alice; Wicker, Emmanuel

    2015-12-01

    For the development of pathogen-informed breeding strategies, identifying the microbial genes involved in interactions with the plant is a critical step. To identify type III effector (T3E) repertoires associated with virulence of the bacterial wilt pathogen Ralstonia solanacearum on Solanaceous crops, we used an original association genetics approach combining DNA microarray data and pathogenicity data on resistant eggplant, pepper, and tomato accessions. From this first screen, 25 T3Es were further full-length polymerase chain reaction-amplified within a 35-strain field collection, to assess their distribution and allelic diversity. Six T3E repertoire groups were identified, within which 11 representative strains were chosen to challenge the bacterial wilt-resistant egg plants 'Dingras multiple Purple' and 'AG91-25', and tomato Hawaii 7996. The virulence or avirulence phenotypes could not be explained by specific T3E repertoires, but rather by individual T3E genes. We identified seven highly avirulence-associated genes, among which ripP2, primarily referenced as conferring avirulence to Arabidopsis thaliana. Interestingly, no T3E was associated with avirulence to both egg-plants. Highly virulence-associated genes were also identified: ripA5_2, ripU, and ripV2. This study should be regarded as a first step toward investigating both avirulence and virulence function of the highlighted genes, but also their evolutionary dynamics in natural R. solanacearum populations. PMID:26368514

  1. Cross-sectional retrospective study of muscle function in patients with glycogen storage disease type III.

    PubMed

    Decostre, Valérie; Laforêt, Pascal; Nadaj-Pakleza, Aleksandra; De Antonio, Marie; Leveugle, Sylvain; Ollivier, Gwenn; Canal, Aurélie; Kachetel, Kahina; Petit, François; Eymard, Bruno; Behin, Anthony; Wahbi, Karim; Labrune, Philippe; Hogrel, Jean-Yves

    2016-09-01

    Glycogen storage disease type III is an inherited metabolic disorder characterized by liver and muscle impairment. This study aimed to identify promising muscle function measures for future studies on natural disease progression and therapeutic trials. The age-effect on the manual muscle testing (MMT), the hand-held dynamometry (HHD), the motor function measure (MFM) and the Purdue pegboard test was evaluated by regression analysis in a cross-sectional retrospective single site study. In patients aged between 13 and 56 years old, the Purdue pegboard test and dynamometry of key pinch and knee extension strength were age-sensitive with annual losses of 1.49, 1.10 and 0.70% of the predicted values (%pred), respectively. The MFM score and handgrip strength were also age-sensitive but only in patients older than 29 and 37 years old with annual losses of 1.42 and 1.84%pred, respectively. Muscle strength assessed by MMT and elbow extension measured by HHD demonstrated an annual loss of less than 0.50%pred and are thus unlikely to be promising outcome measures for future clinical trials. In conclusion, our results identified age-sensitive outcomes from retrospective data and may serve for future longitudinal studies in which an estimation of the minimal number of subjects is provided.

  2. Towards the Identification of Type III Effectors Associated with Ralstonia solanacearum Virulence on Tomato and Eggplant.

    PubMed

    Pensec, Flora; Lebeau, Aurore; Daunay, M C; Chiroleu, Frédéric; Guidot, Alice; Wicker, Emmanuel

    2015-12-01

    For the development of pathogen-informed breeding strategies, identifying the microbial genes involved in interactions with the plant is a critical step. To identify type III effector (T3E) repertoires associated with virulence of the bacterial wilt pathogen Ralstonia solanacearum on Solanaceous crops, we used an original association genetics approach combining DNA microarray data and pathogenicity data on resistant eggplant, pepper, and tomato accessions. From this first screen, 25 T3Es were further full-length polymerase chain reaction-amplified within a 35-strain field collection, to assess their distribution and allelic diversity. Six T3E repertoire groups were identified, within which 11 representative strains were chosen to challenge the bacterial wilt-resistant egg plants 'Dingras multiple Purple' and 'AG91-25', and tomato Hawaii 7996. The virulence or avirulence phenotypes could not be explained by specific T3E repertoires, but rather by individual T3E genes. We identified seven highly avirulence-associated genes, among which ripP2, primarily referenced as conferring avirulence to Arabidopsis thaliana. Interestingly, no T3E was associated with avirulence to both egg-plants. Highly virulence-associated genes were also identified: ripA5_2, ripU, and ripV2. This study should be regarded as a first step toward investigating both avirulence and virulence function of the highlighted genes, but also their evolutionary dynamics in natural R. solanacearum populations.

  3. Substrate-Activated Conformational Switch on Chaperones Encodes aTargeting Signal in Type III Secretion

    PubMed Central

    Chen, Li; Ai, Xuanjun; Portaliou, Athina G.; Minetti, Conceicao A.S.A.; Remeta, David P.; Economou, Anastassios; Kalodimos, Charalampos G.

    2013-01-01

    SUMMARY Targeting of type III secretion proteins at the injectisome is an important process in bacterial virulence. Nevertheless, how the injectisome specifically recognizes TTS substrates among all bacterial proteins is unknown. A TTS peripheral membrane ATPase protein located at the base of the injectisome has been implicated in the targeting process. We have investigated the targeting of the EspA filament protein and its cognate chaperone CesAB to the EscN ATPase of the enteropathogenic E. coli (EPEC). We show that EscN selectively engages the EspA-loaded CesAB, but not the unliganded CesAB. Structure analysis revealed that the targeting signal is encoded in a disorder-order structural transition in CesAB that is elicited only upon binding of its physiological substrate, EspA. Abrogation of the interaction between the CesAB–EspA complex and EscN resulted in severe secretion and infection defects. We further show that the targeting and secretion signals are distinct and the two processes are likely regulated by different mechanisms. PMID:23523349

  4. A bacterial type III secretion-based protein delivery tool for broad applications in cell biology

    PubMed Central

    Ittig, Simon J.; Schmutz, Christoph; Kasper, Christoph A.; Amstutz, Marlise; Schmidt, Alexander; Sauteur, Loïc; Vigano, M. Alessandra; Low, Shyan Huey; Affolter, Markus; Cornelis, Guy R.; Nigg, Erich A.

    2015-01-01

    Methods enabling the delivery of proteins into eukaryotic cells are essential to address protein functions. Here we propose broad applications to cell biology for a protein delivery tool based on bacterial type III secretion (T3S). We show that bacterial, viral, and human proteins, fused to the N-terminal fragment of the Yersinia enterocolitica T3S substrate YopE, are effectively delivered into target cells in a fast and controllable manner via the injectisome of extracellular bacteria. This method enables functional interaction studies by the simultaneous injection of multiple proteins and allows the targeting of proteins to different subcellular locations by use of nanobody-fusion proteins. After delivery, proteins can be freed from the YopE fragment by a T3S-translocated viral protease or fusion to ubiquitin and cleavage by endogenous ubiquitin proteases. Finally, we show that this delivery tool is suitable to inject proteins in living animals and combine it with phosphoproteomics to characterize the systems-level impact of proapoptotic human truncated BID on the cellular network. PMID:26598622

  5. a Computational Approach to Explore Protein Translocation Through Type III Secretion Apparatus

    NASA Astrophysics Data System (ADS)

    Rathinavelan, Thenmalarchelvi; Im, Wonpil

    2010-01-01

    Many Gram-negative bacteria initiate infections by injecting effector proteins into host cells through the type III secretion apparatus (TTSA) that is comprised of a basal body, a needle, and a tip. The needle channel is formed by the assembly of a single needle protein. To explore the export mechanisms of MxiH needle protein through the needle of Shigella flexneri, an essential step during needle assembly, we have performed steered molecular dynamics simulations in implicit solvent. Interestingly, the electronegative channel interior creates an energy barrier for MxiH to enter the channel, while the same may facilitate the ejection of the effectors into host cells. Structurally-known basal regions and ATPase underneath the basal region have also such electronegative interior, while effector proteins have considerable electronegative patches on their surfaces. Based on these observations, we propose a repulsive electrostatic mechanism for protein translocation through the TTSA. This mechanism is supported by the suggestion that an ATPase is required for protein translocation through these nanomachines, which may provide the energy to overcome the initial electrostatic energy barrier. A similar mechanism may be applicable to macromolecular channels in other secretion systems or viruses through which proteins or nucleic acids are transported.

  6. Crystal structure of Spa40, the specificity switch for the Shigella flexneri type III secretion system

    PubMed Central

    Deane, Janet E; Graham, Stephen C; Mitchell, Edward P; Flot, David; Johnson, Steven; Lea, Susan M

    2008-01-01

    The pathogenic bacterium Shigella flexneri uses a type III secretion system to inject virulence factors from the bacterial cytosol directly into host cells. The machinery that identifies secretion substrates and controls the export of extracellular components and effector proteins consists of several inner-membrane and cytoplasmic proteins. One of the inner membrane components, Spa40, belongs to a family of proteins proposed to regulate the switching of substrate specificity of the export apparatus. We show that Spa40 is cleaved within the strictly conserved amino acid sequence NPTH and substitution of the proposed autocatalytic residue abolishes cleavage. Here we also report the crystal structure of the cytoplasmic complex Spa40C and compare it with the recent structures of the homologues from Escherichia coli and Salmonella typhimurium. These structures reveal the tight association of the cleaved fragments and show that the conserved NPTH sequence lies on a loop which, when cleaved, swings away from the catalytic N257 residue, resulting in different surface features in this region. This structural rearrangement suggests a mechanism by which non-cleaving forms of these proteins interfere with correct substrate switching of the apparatus. PMID:18485071

  7. Type III secretion needle proteins induce cell signaling and cytokine secretion via Toll-like receptors.

    PubMed

    Jessen, Danielle L; Osei-Owusu, Patrick; Toosky, Melody; Roughead, William; Bradley, David S; Nilles, Matthew L

    2014-06-01

    Pathogens are recognized by hosts by use of various receptors, including the Toll-like receptor (TLR) and Nod-like receptor (NLR) families. Ligands for these varied receptors, including bacterial products, are identified by the immune system, resulting in development of innate immune responses. Only a couple of components from type III secretion (T3S) systems are known to be recognized by TLR or NLR family members. Known T3S components that are detected by pattern recognition receptors (PRRs) are (i) flagellin, detected by TLR5 and NLRC4 (Ipaf); and (ii) T3S rod proteins (PrgJ and homologs) and needle proteins (PrgI and homologs), detected by NAIP and the NLRC4 inflammasome. In this report, we characterize the induction of proinflammatory responses through TLRs by the Yersinia pestis T3S needle protein, YscF, the Salmonella enterica needle proteins PrgI and SsaG, and the Shigella needle protein, MxiH. More specifically, we determine that the proinflammatory responses occur through TLR2 and -4. These data support the hypothesis that T3S needles have an unrecognized role in bacterial pathogenesis by modulating immune responses. PMID:24643544

  8. Structure of a bacterial type III secretion system in contact with a host membrane in situ

    NASA Astrophysics Data System (ADS)

    Nans, Andrea; Kudryashev, Mikhail; Saibil, Helen R.; Hayward, Richard D.

    2015-12-01

    Many bacterial pathogens of animals and plants use a conserved type III secretion system (T3SS) to inject virulence effector proteins directly into eukaryotic cells to subvert host functions. Contact with host membranes is critical for T3SS activation, yet little is known about T3SS architecture in this state or the conformational changes that drive effector translocation. Here we use cryo-electron tomography and sub-tomogram averaging to derive the intact structure of the primordial Chlamydia trachomatis T3SS in the presence and absence of host membrane contact. Comparison of the averaged structures demonstrates a marked compaction of the basal body (4 nm) occurs when the needle tip contacts the host cell membrane. This compaction is coupled to a stabilization of the cytosolic sorting platform-ATPase. Our findings reveal the first structure of a bacterial T3SS from a major human pathogen engaged with a eukaryotic host, and reveal striking `pump-action' conformational changes that underpin effector injection.

  9. Type III Interferons Produced by Human Placental Trophoblasts Confer Protection against Zika Virus Infection.

    PubMed

    Bayer, Avraham; Lennemann, Nicholas J; Ouyang, Yingshi; Bramley, John C; Morosky, Stefanie; Marques, Ernesto Torres De Azeved; Cherry, Sara; Sadovsky, Yoel; Coyne, Carolyn B

    2016-05-11

    During mammalian pregnancy, the placenta acts as a barrier between the maternal and fetal compartments. The recently observed association between Zika virus (ZIKV) infection during human pregnancy and fetal microcephaly and other anomalies suggests that ZIKV may bypass the placenta to reach the fetus. This led us to investigate ZIKV infection of primary human trophoblasts (PHTs), which are the barrier cells of the placenta. We discovered that PHT cells from full-term placentas are refractory to ZIKV infection. In addition, medium from uninfected PHT cells protects non-placental cells from ZIKV infection. PHT cells constitutively release the type III interferon (IFN) IFNλ1, which functions in both a paracrine and autocrine manner to protect trophoblast and non-trophoblast cells from ZIKV infection. Our data suggest that for ZIKV to access the fetal compartment, it must evade restriction by trophoblast-derived IFNλ1 and other trophoblast-specific antiviral factors and/or use alternative strategies to cross the placental barrier.

  10. Cytosporone B, an inhibitor of the type III secretion system of Salmonella enterica serovar Typhimurium.

    PubMed

    Li, Jianfang; Lv, Chao; Sun, Weiyang; Li, Zhenyu; Han, Xiaowei; Li, Yaoyao; Shen, Yuemao

    2013-05-01

    Bacterial virulence factors have been increasingly regarded as attractive targets for development of novel antibacterial agents. Virulence inhibitors are less likely to generate bacterial resistance, which makes them superior to traditional antibiotics that target bacterial viability. Salmonella enterica serovar Typhimurium, an important food-borne human pathogen, has type III secretion system (T3SS) as its major virulence factor. T3SS secretes effector proteins to facilitate invasion into host cells. In this study, we identified several analogs of cytosporone B (Csn-B) that strongly block the secretion of Salmonella pathogenicity island 1 (SPI-1)-associated effector proteins, without affecting the secretion of flagellar protein FliC in vitro. Csn-B and two other derivatives exhibited a strong inhibitory effect on SPI-1-mediated invasion to HeLa cells, while no significant toxicity to bacteria was observed. Nucleoid proteins Hha and H-NS bind to the promoters of SPI-1 regulator genes hilD, hilC, and rtsA to repress their expression and consequently regulate the expression of SPI-1 apparatus and effector genes. We found that Csn-B upregulated the transcription of hha and hns, implying that Csn-B probably affected the secretion of effectors through the Hha-H-NS regulatory pathway. In summary, this study presented an effective SPI-1 inhibitor, Csn-B, which may have potential in drug development against antibiotic-resistant Salmonella.

  11. Bacterial type III secretion systems: specialized nanomachines for protein delivery into target cells

    PubMed Central

    Galán, Jorge E.; Lara-Tejero, Maria; Marlovits, Thomas C.; Wagner, Samuel

    2015-01-01

    One of the most exciting developments in the field of bacterial pathogenesis in recent years is the discovery that many pathogens utilized complex nanomachines to deliver bacterially encoded effector proteins into target eukaryotic cells. These effector proteins modulate a variety of cellular functions for the pathogen’s benefit. One of these protein-delivery machines is the type III secretion system (T3SS). T3SSs are widespread in nature and are encoded not only by bacteria pathogenic to vertebrates or plants, but also by bacteria that are symbiotic to plants or insects. A central component of T3SSs is the needle complex, a supramolecular structure that mediates the passage of the secreted proteins across the bacterial envelope. Working in conjunction with several cytoplasmic components, the needle complex engages specific substrates in sequential order, moves them across the bacterial envelope, and ultimately delivers them into eukaryotic cells. The central role of T3SSs in pathogenesis makes them great targets for novel antimicrobial strategies. PMID:25002086

  12. Type III Secretion Needle Proteins Induce Cell Signaling and Cytokine Secretion via Toll-Like Receptors

    PubMed Central

    Jessen, Danielle L.; Osei-Owusu, Patrick; Toosky, Melody; Roughead, William; Bradley, David S.

    2014-01-01

    Pathogens are recognized by hosts by use of various receptors, including the Toll-like receptor (TLR) and Nod-like receptor (NLR) families. Ligands for these varied receptors, including bacterial products, are identified by the immune system, resulting in development of innate immune responses. Only a couple of components from type III secretion (T3S) systems are known to be recognized by TLR or NLR family members. Known T3S components that are detected by pattern recognition receptors (PRRs) are (i) flagellin, detected by TLR5 and NLRC4 (Ipaf); and (ii) T3S rod proteins (PrgJ and homologs) and needle proteins (PrgI and homologs), detected by NAIP and the NLRC4 inflammasome. In this report, we characterize the induction of proinflammatory responses through TLRs by the Yersinia pestis T3S needle protein, YscF, the Salmonella enterica needle proteins PrgI and SsaG, and the Shigella needle protein, MxiH. More specifically, we determine that the proinflammatory responses occur through TLR2 and -4. These data support the hypothesis that T3S needles have an unrecognized role in bacterial pathogenesis by modulating immune responses. PMID:24643544

  13. Formulation and immunogenicity studies of type III secretion system needle antigens as vaccine candidates.

    PubMed

    Barrett, Brooke S; Markham, Aaron P; Esfandiary, Reza; Picking, Wendy L; Picking, William D; Joshi, Sangeeta B; Middaugh, C Russell

    2010-11-01

    Bacterial infections caused by Shigella flexneri, Salmonella typhimurium, and Burkholderia pseudomallei are currently difficult to prevent due to the lack of a licensed vaccine. Here we present formulation and immunogenicity studies for the three type III secretion system (TTSS) needle proteins MxiH(Δ5), PrgI(Δ5), and BsaL(Δ5) (each truncated by five residues at its C terminus) as potential candidates for vaccine development. These antigens are found to be thermally stabilized by the presence of carbohydrates and polyols. Additionally, all adsorb readily to aluminum hydroxide apparently through a combination of hydrogen bonds and/or Van der Waals forces. The interaction of these proteins with the aluminum-based adjuvant changes with time resulting in varying degrees of irreversible binding. Peptide maps of desorbed protein, however, suggest that chemical changes are not responsible for this irreversible association. The ability of MxiH(Δ5) and PrgI(Δ5) to elicit strong humoral immune responses was tested in a murine model. When administered intramuscularly as monomers, the needle components exhibited dose dependent immunogenic behavior. The polymerized version of MxiH was exceptionally immunogenic even at low doses. The responses of both monomeric and polymerized forms were boosted by adsorption to an aluminum salt adjuvant.

  14. Formulation and Immunogenicity studies of Type III Secretion System needle antigens as Vaccine Candidates

    PubMed Central

    Barrett, Brooke S.; Markham, Aaron P.; Esfandiary, Reza; Picking, Wendy L.; Picking, William D.; Joshi, Sangeeta B.; Middaugh, C. Russell

    2013-01-01

    Bacterial infections caused by Shigella flexneri, Salmonella typhimurium and Burkholderia pseudomallei are currently difficult to prevent due to the lack of a licensed vaccine. Here we present formulation and immunogenicity studies for the three type III secretion system (TTSS) needle proteins MxiHΔ5, PrgIΔ5 and BsaLΔ5 (each truncated by five residues at its C terminus) as potential candidates for vaccine development. These antigens are found to be thermally stabilized by the presence of carbohydrates and polyols. Additionally, all adsorb readily to aluminum hydroxide apparently through a combination of hydrogen bonds and/or Van der Waals forces. The interaction of these proteins with the aluminum-based adjuvant changes with time to resulting in varying degrees of irreversible binding. Peptide maps of desorbed protein, however, suggest that chemical changes are not responsible for this irreversible association. The ability of MxiHΔ5 and PrgIΔ5 to elicit strong humoral immune responses was tested in a murine model. When administered intramuscularly as monomers, the needle components exhibited dose dependent immunogenic behavior. The polymerized version of MxiH was exceptionally immunogenic even at low doses. The responses of both monomeric and polymerized forms were boosted by adsorption to an aluminum salt adjuvant. PMID:20845448

  15. The Salmonella Type III Secretion System Inner Rod Protein PrgJ Is Partially Folded*

    PubMed Central

    Zhong, Dalian; Lefebre, Matthew; Kaur, Kawaljit; McDowell, Melanie A.; Gdowski, Courtney; Jo, Sunhwan; Wang, Yu; Benedict, Stephen H.; Lea, Susan M.; Galan, Jorge E.; De Guzman, Roberto N.

    2012-01-01

    The type III secretion system (T3SS) is essential in the pathogenesis of many bacteria. The inner rod is important in the assembly of the T3SS needle complex. However, the atomic structure of the inner rod protein is currently unknown. Based on computational methods, others have suggested that the Salmonella inner rod protein PrgJ is highly helical, forming a folded 3 helix structure. Here we show by CD and NMR spectroscopy that the monomeric form of PrgJ lacks a tertiary structure, and the only well-structured part of PrgJ is a short α-helix at the C-terminal region from residues 65–82. Disruption of this helix by glycine or proline mutation resulted in defective assembly of the needle complex, rendering bacteria incapable of secreting effector proteins. Likewise, CD and NMR data for the Shigella inner rod protein MxiI indicate this protein lacks a tertiary structure as well. Our results reveal that the monomeric forms of the T3SS inner rod proteins are partially folded. PMID:22654099

  16. An Uncommon Case of Type III Endoleak Treated with a Custom-made Thoracic Stent Graft.

    PubMed

    Massara, Mafalda; Barillà, David; Franco, Gaetana; Volpe, Alberto; Serra, Raffaele; De Caridi, Giovanni; Alberti, Antonino; Volpe, Pietro

    2016-08-01

    Endovascular aortic repair (EVAR) has been shown to be a valid and minimally invasive alternative to open abdominal aortic aneurysm repair. A major shortcoming for EVAR is the need to submit patients to regular follow-up to detect potential complications such as endoleak, limb occlusion, aneurysm expansion, aneurysm rupture, infection, structural failure, and migration. In this case report, we describe an uncommon case of late type III endoleak due to complete detachment of the stent-graft main body segment from its suprarenal uncovered fixation stent. It was treated with a custom-made Relay(®) NBS Plus (Bolton Medical, Barcelona, Spain) thoracic stent graft which also provided extra suprarenal fixation of the thoracic stent graft in the proximal neck. The postoperative period was uneventful and a computed tomography scan 1 year later revealed proper positioning of the stent graft and no signs of endoleak. The successful strategy chosen to correct this complication was at the same time original and infrequent, and also avoided potential complications related to open surgical repair and general anesthesia. PMID:27263819

  17. Type III Secretion-Dependent Sensitivity of Escherichia coli O157 to Specific Ketolides.

    PubMed

    Fernandez-Brando, Romina J; Yamaguchi, Nao; Tahoun, Amin; McAteer, Sean P; Gillespie, Trudi; Wang, Dai; Argyle, Sally A; Palermo, Marina S; Gally, David L

    2015-11-02

    A subset of Gram-negative bacterial pathogens uses a type III secretion system (T3SS) to open up a conduit into eukaryotic cells in order to inject effector proteins. These modulate pathways to enhance bacterial colonization. In this study, we screened established bioactive compounds for any that could repress T3SS expression in enterohemorrhagic Escherichia coli (EHEC) O157. The ketolides telithromycin and, subsequently, solithromycin both demonstrated repressive effects on expression of the bacterial T3SS at sub-MICs, leading to significant reductions in bacterial binding and actin-rich pedestal formation on epithelial cells. Preincubation of epithelial cells with solithromycin resulted in significantly less attachment of E. coli O157. Moreover, bacteria expressing the T3SS were more susceptible to solithromycin, and there was significant preferential killing of E. coli O157 bacteria when they were added to epithelial cells that had been preexposed to the ketolide. This killing was dependent on expression of the T3SS. Taken together, this research indicates that the ketolide that has accumulated in epithelial cells may traffic back into the bacteria via the T3SS. Considering that neither ketolide induces the SOS response, nontoxic members of this class of antibiotics, such as solithromycin, should be considered for future testing and trials evaluating their use for treatment of EHEC infections. These antibiotics may also have broader significance for treating infections caused by other pathogenic bacteria, including intracellular bacteria, that express a T3SS.

  18. Fermentation of Metroxylon sagu resistant starch type III by Lactobacillus sp. and Bifidobacterium bifidum.

    PubMed

    Siew-Wai, Loo; Zi-Ni, Tan; Karim, Alias A; Hani, Norziah M; Rosma, Ahmad

    2010-02-24

    The in vitro fermentability of sago (Metroxylon sagu) resistant starch type III (RS(3)) by selected probiotic bacteria was investigated. Sago RS(3) with 12% RS content was prepared by enzymatic debranching of native sago starch with pullulanase enzyme, followed by autoclaving, cooling, and annealing. The fermentation of sago RS(3) by L. acidophilus FTCC 0291, L. bulgaricus FTCC 0411, L. casei FTCC 0442, and B. bifidum BB12 was investigated by observing the bacterial growth, carbohydrate consumption profiles, pH changes, and total short chain fatty acids (SCFA) produced in the fermentation media. Comparisons were made with commercial fructo-oligosaccharide (FOS), Hi-maize 1043, and Hi-maize 240. Submerged fermentations were conducted in 30 mL glass vials for 24 h at 37 degrees C in an oven without shaking. The results indicated that fermentation of sago RS(3) significantly (P < 0.05) yielded the highest count of Lactobacillus sp. accompanied by the largest reduction in pH of the medium. Sago RS(3) was significantly the most consumed substrate compared to FOS and Hi-maizes. PMID:20121195

  19. A type III ACC synthase, ACS7, is involved in root gravitropism in Arabidopsis thaliana

    PubMed Central

    Chang, Ing-Feng

    2013-01-01

    Ethylene is an important plant hormone that regulates developmental processes in plants. The ethylene biosynthesis pathway is a highly regulated process at both the transcriptional and post-translational level. The transcriptional regulation of these ethylene biosynthesis genes is well known. However, post-translational modifications of the key ethylene biosynthesis enzyme 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS) are little understood. In vitro kinase assays were conducted on the type III ACS, AtACS7, fusion protein and peptides to determine whether the AtACS7 protein can be phosphorylated by calcium-dependent protein kinase (CDPK). AtACS7 was phosphorylated at Ser216, Thr296, and Ser299 by AtCDPK16 in vitro. To investigate further the function of the ACS7 gene in Arabidopsis, an acs7-1 loss-of-function mutant was isolated. The acs7-1 mutant exhibited less sensitivity to the inhibition of root gravitropism by treatment with the calcium chelator ethylene glycol tetraacetic acid (EGTA). Seedlings were treated with gradient concentrations of ACC. The results showed that a certain concentration of ethylene enhanced the gravity response. Moreover, the acs7-1 mutant was less sensitive to inhibition of the gravity response by treatment with the auxin polar transport inhibitor 1-naphthylphthalamic acid, but exogenous ACC application recovered root gravitropism. Altogether, the results indicate that AtACS7 is involved in root gravitropism in a calcium-dependent manner in Arabidopsis. PMID:23943848

  20. Type III Secretion-Dependent Sensitivity of Escherichia coli O157 to Specific Ketolides

    PubMed Central

    Fernandez-Brando, Romina J.; Yamaguchi, Nao; Tahoun, Amin; McAteer, Sean P.; Gillespie, Trudi; Wang, Dai; Argyle, Sally A.; Palermo, Marina S.

    2015-01-01

    A subset of Gram-negative bacterial pathogens uses a type III secretion system (T3SS) to open up a conduit into eukaryotic cells in order to inject effector proteins. These modulate pathways to enhance bacterial colonization. In this study, we screened established bioactive compounds for any that could repress T3SS expression in enterohemorrhagic Escherichia coli (EHEC) O157. The ketolides telithromycin and, subsequently, solithromycin both demonstrated repressive effects on expression of the bacterial T3SS at sub-MICs, leading to significant reductions in bacterial binding and actin-rich pedestal formation on epithelial cells. Preincubation of epithelial cells with solithromycin resulted in significantly less attachment of E. coli O157. Moreover, bacteria expressing the T3SS were more susceptible to solithromycin, and there was significant preferential killing of E. coli O157 bacteria when they were added to epithelial cells that had been preexposed to the ketolide. This killing was dependent on expression of the T3SS. Taken together, this research indicates that the ketolide that has accumulated in epithelial cells may traffic back into the bacteria via the T3SS. Considering that neither ketolide induces the SOS response, nontoxic members of this class of antibiotics, such as solithromycin, should be considered for future testing and trials evaluating their use for treatment of EHEC infections. These antibiotics may also have broader significance for treating infections caused by other pathogenic bacteria, including intracellular bacteria, that express a T3SS. PMID:26525795

  1. Recent neutrino data and type III seesaw model with discrete symmetry

    NASA Astrophysics Data System (ADS)

    Ahn, Y. H.; Kim, C. S.; Oh, Sechul

    2012-07-01

    In light of the recent neutrino experiment results from the Daya Bay and RENO Collaborations, we study phenomenology of neutrino mixing angles in the type III seesaw model with a discrete A4×Z2 symmetry, whose spontaneously breaking scale is much higher than the electroweak scale. At tree level, the tri-bimaximal (TBM) form of the lepton mixing matrix can be obtained from leptonic Yukawa interactions in a natural way. We introduce all possible effective dimension-five operators, invariant under the standard model gauge group and A4×Z2, and explicitly show that they induce a deviation of the lepton mixing from the TBM mixing matrix, which can explain a large mixing angle θ13 together with small deviations of the solar and atmospheric mixing angles from the TBM. Two possible scenarios are investigated, by taking into account either negligible or sizable contributions from the light charged lepton sector to the lepton mixing matrix. Especially it is found in the latter scenario that all the neutrino experimental data, including the recent best-fit value of θ13=8.68°, can be accommodated. The leptonic CP violation characterized by the Jarlskog invariant JCP has a nonvanishing value, indicating a signal of maximal CP violation.

  2. Using Transcriptional Control To Increase Titers of Secreted Heterologous Proteins by the Type III Secretion System

    PubMed Central

    Metcalf, Kevin J.; Finnerty, Casey; Azam, Anum; Valdivia, Elias

    2014-01-01

    The type III secretion system (T3SS) encoded at the Salmonella pathogenicity island 1 (SPI-1) locus secretes protein directly from the cytosol to the culture media in a concerted, one-step process, bypassing the periplasm. While this approach is attractive for heterologous protein production, product titers are too low for many applications. In addition, the expression of the SPI-1 gene cluster is subject to native regulation, which requires culturing conditions that are not ideal for high-density growth. We used transcriptional control to increase the amount of protein that is secreted into the extracellular space by the T3SS of Salmonella enterica. The controlled expression of the gene encoding SPI-1 transcription factor HilA circumvents the requirement of endogenous induction conditions and allows for synthetic induction of the secretion system. This strategy increases the number of cells that express SPI-1 genes, as measured by promoter activity. In addition, protein secretion titer is sensitive to the time of addition and the concentration of inducer for the protein to be secreted and SPI-1 gene cluster. Overexpression of hilA increases secreted protein titer by >10-fold and enables recovery of up to 28 ± 9 mg/liter of secreted protein from an 8-h culture. We also demonstrate that the protein beta-lactamase is able to adopt an active conformation after secretion, and the increase in secreted titer from hilA overexpression also correlates to increased enzyme activity in the culture supernatant. PMID:25038096

  3. Early Umbilical Cord Blood-Derived Stem Cell Transplantation Does Not Prevent Neurological Deterioration in Mucopolysaccharidosis Type III.

    PubMed

    Welling, Lindsey; Marchal, Jan Pieter; van Hasselt, Peter; van der Ploeg, Ans T; Wijburg, Frits A; Boelens, Jaap Jan

    2015-01-01

    Mucopolysaccharidosis type III (MPS III), or Sanfilippo disease, is a neurodegenerative lysosomal storage disease (LSD) caused by defective lysosomal degradation of heparan sulfate (HS). No effective disease-modifying therapy is yet available. In contrast to some other neuronopathic LSDs, bone marrow-derived hematopoietic stem cell transplantation (HSCT) fails to prevent neurological deterioration in MPS III patients. We report on the 5-year outcome of early transplantation, i.e., before onset of clinical neurological disease, in combination with the use of umbilical cord blood-derived hematopoietic stem cells (UCBT), in two MPS III patients. Both patients had a normal developmental quotient at the time of UCBT. One patient had a combination of mutations predicting a classical severe phenotype (MPS IIIA), and one patient (MPS IIIB) had mutations predicting a very attenuated phenotype. Transplantation was uncomplicated with full engraftment of donor cells in both.Both patients showed progressive neurological deterioration with regression of cognitive skills and behavioral disturbances during 5 years after successful UCBT, comparable to the natural history of patients with the same combination of mutations. The concentration of HS in CSF in the patient with the attenuated phenotype of MPS IIIB 2 years after UCBT was very high and in the range of untreated MPS III patients.We conclude that the course of cognitive development, behavioral problems, and absence of biochemical correction in CSF demonstrate the absence of relevant effect of UCBT in MPS III patients, even when performed before clinical onset of CNS disease. PMID:25256447

  4. Muscle Ultrasound in Patients with Glycogen Storage Disease Types I and III.

    PubMed

    Verbeek, Renate J; Sentner, Christiaan P; Smit, G Peter A; Maurits, Natasha M; Derks, Terry G J; van der Hoeven, Johannes H; Sival, Deborah A

    2016-01-01

    In glycogen storage diseases (GSDs), improved longevity has resulted in the need for neuromuscular surveillance. In 12 children and 14 adults with the "hepatic" (GSD-I) and "myopathic" (GSD-III) phenotypes, we cross-sectionally assessed muscle ultrasound density (MUD) and muscle force. Children with both "hepatic" and "myopathic" GSD phenotypes had elevated MUD values (MUD Z-scores: GSD-I > 2.5 SD vs. GSD-III > 1 SD, p < 0.05) and muscle weakness (GSD-I muscle force; p < 0.05) of myopathic distribution. In "hepatic" GSD-I adults, MUD stabilized (GSD-I adults vs. GSD-I children, not significant), concurring with moderate muscle weakness (GSD-I adults vs. healthy matched pairs, p < 0.05). In "myopathic" GSD-III adults, MUD increased with age (MUD-GSD III vs. age: r = 0.71-0.83, GSD-III adults > GSD-III children, p < 0.05), concurring with pronounced muscle weakness (GSD-III adults vs. GSD-I adults, p < 0.05) of myopathic distribution. Children with "hepatic" and "myopathic" GSD phenotypes were both found to have myopathy. Myopathy stabilizes in "hepatic" GSD-I adults, whereas it progresses in "myopathic" GSD-III adults. Muscle ultrasonography provides an excellent, non-invasive tool for neuromuscular surveillance per GSD phenotype.

  5. Alpha C Protein as a Carrier for Type III Capsular Polysaccharide and as a Protective Protein in Group B Streptococcal Vaccines

    PubMed Central

    Gravekamp, Claudia; Kasper, Dennis L.; Paoletti, Lawrence C.; Madoff, Lawrence C.

    1999-01-01

    The alpha C protein, a protective surface protein of group B streptococci (GBS), is present in most non-type III GBS strains. Conjugate vaccines composed of the alpha C protein and type III capsular polysaccharide (CPS) might be protective against most GBS infections. In this study, the type III CPS was covalently coupled to full-length, nine-repeat alpha C protein (resulting in III-α9r conjugate vaccine) or to two-repeat alpha C protein (resulting in III-α2r conjugate vaccine) by reductive amination. Initial experiments with the III-α9r vaccine showed that it was poorly immunogenic in mice with respect to both vaccine antigens and was suboptimally efficacious in providing protection in mice against challenge with GBS. Therefore, modified vaccination protocols were used with the III-α2r vaccine. Female mice were immunized three times with 0.5, 5, or 20 μg of the III-α2r vaccine with an aluminum hydroxide adjuvant and bred. Ninety-five percent of neonatal mice born to dams immunized with the III-α2r vaccine survived challenge with GBS expressing type III CPS, and 60% survived challenge with GBS expressing wild-type (nine-repeat) alpha C protein; 18 and 17%, respectively, of mice in the negative control groups survived (P, <0.0001). These protection levels did not differ significantly from those obtained with the type III CPS-tetanus toxoid conjugate vaccine and the unconjugated two-repeat alpha C protein, which protected 98 and 58% of neonates from infection with GBS expressing type III CPS or the alpha C protein, respectively. Thus, the two-repeat alpha C protein in the vaccine was immunogenic and simultaneously enhanced the immunogenicity of type III CPS. III-α vaccines may be alternatives to GBS polysaccharide-tetanus toxoid vaccines, eliciting additional antibodies protective against GBS infection. PMID:10225912

  6. QCD corrections to pair production of Type III Seesaw leptons at hadron colliders

    NASA Astrophysics Data System (ADS)

    Ruiz, Richard

    2015-12-01

    If kinematically accessible, hadron collider experiments provide an ideal laboratory for the direct production of heavy lepton partners in Seesaw models. In the context of the Type III Seesaw Mechanism, the O({α}_s) rate and shape corrections are presented for the pair production of hypothetical, heavy SU(2) L triplet leptons in pp collisions at √{s} = 13, 14 and 100TeV. The next-to-leading order (NLO) K-factors span, approximately, K NLO = 1 .1 - 1 .4 for both charged current and neutral current processes over a triplet mass range m T = 100 GeV - 2 TeV. Total production cross sections exhibit a - 6 % + 5 % scale dependence at 14 TeV and ±1% at 100 TeV. The NLO differential K-factors for heavy lepton kinematics are largely flat, suggesting that na¨ıve scaling by the total K NLO is reasonably justified. The resummed transverse momentum distribution of the dilepton system is presented at leading logarithmic (LL) accuracy. The effects of resummation are large in TeV-scale dilepton systems. Discovery potential to heavy lepton pairs at 14 and 100 TeV is briefly explored: at the High-Luminosity LHC, we estimate a 4 .8 - 6 .3 σ discovery potential maximally for m T = 1 .5 - 1 .6 TeV after 3000 fb-1. With 300 (3000) fb-1, there is 2σ sensitivity up to m T = 1 .3 - 1 .4 TeV (1 .7 - 1 .8 TeV) in the individual channels. At 100 TeV and with 10 fb-1, a 5 σ discovery can be achieved for m T = 1 .4 - 1 .6 TeV. Due to the factorization properties of Drell-Yan-type systems, the fixed order and resummed calculations reduce to convolutions over tree-level quantities.

  7. Cross-Talk between the Aeromonas hydrophila Type III Secretion System and Lateral Flagella System.

    PubMed

    Zhao, Yu-Hang; Shaw, Jonathan G

    2016-01-01

    Aeromonas hydrophila is responsible for aeromonad septicaemia in fish, and gastroenteritis and wound infections in humans. The type III secretion system (T3SS) is utilized by aeromonads to inject protein effectors directly into host cells. One of the major genetic regulators of the T3SS in several bacterial species is the AraC-like protein ExsA. Previous studies have suggested a link between T3SS regulation and lateral flagella expression. The aim of this study was to determine the genetic regulation of the T3SS and its potential interaction with the lateral flagella system in A. hydrophila. To investigate the genes encoding the T3SS regulatory components exsA, exsD, exsC, and exsE were mutated and the activities of the T3SS promoters were measured in wild type and mutant backgrounds demonstrating a regulatory network. The Exs proteins were shown to interact with each other by BACTH assay and Far-Western Blot. The findings suggested a regulatory cascade in which ExsE was bound to the chaperone protein ExsC. When ExsC was free it sequestered the anti-activator ExsD thus stopping the inhibition of the T3SS master regulator ExsA allowing T3SS expression. The T3SS regulatory components were also shown to affect the expression of the lateral flagella system. The activities of the lateral flagella promoters were shown to be repressed by the absence of ExsD and ExsE, suggesting that the T3SS master regulator ExsA was a negative regulator of the lateral flagella system. PMID:27656180

  8. Cross-Talk between the Aeromonas hydrophila Type III Secretion System and Lateral Flagella System

    PubMed Central

    Zhao, Yu-Hang; Shaw, Jonathan G.

    2016-01-01

    Aeromonas hydrophila is responsible for aeromonad septicaemia in fish, and gastroenteritis and wound infections in humans. The type III secretion system (T3SS) is utilized by aeromonads to inject protein effectors directly into host cells. One of the major genetic regulators of the T3SS in several bacterial species is the AraC-like protein ExsA. Previous studies have suggested a link between T3SS regulation and lateral flagella expression. The aim of this study was to determine the genetic regulation of the T3SS and its potential interaction with the lateral flagella system in A. hydrophila. To investigate the genes encoding the T3SS regulatory components exsA, exsD, exsC, and exsE were mutated and the activities of the T3SS promoters were measured in wild type and mutant backgrounds demonstrating a regulatory network. The Exs proteins were shown to interact with each other by BACTH assay and Far-Western Blot. The findings suggested a regulatory cascade in which ExsE was bound to the chaperone protein ExsC. When ExsC was free it sequestered the anti-activator ExsD thus stopping the inhibition of the T3SS master regulator ExsA allowing T3SS expression. The T3SS regulatory components were also shown to affect the expression of the lateral flagella system. The activities of the lateral flagella promoters were shown to be repressed by the absence of ExsD and ExsE, suggesting that the T3SS master regulator ExsA was a negative regulator of the lateral flagella system.

  9. Cross-Talk between the Aeromonas hydrophila Type III Secretion System and Lateral Flagella System

    PubMed Central

    Zhao, Yu-Hang; Shaw, Jonathan G.

    2016-01-01

    Aeromonas hydrophila is responsible for aeromonad septicaemia in fish, and gastroenteritis and wound infections in humans. The type III secretion system (T3SS) is utilized by aeromonads to inject protein effectors directly into host cells. One of the major genetic regulators of the T3SS in several bacterial species is the AraC-like protein ExsA. Previous studies have suggested a link between T3SS regulation and lateral flagella expression. The aim of this study was to determine the genetic regulation of the T3SS and its potential interaction with the lateral flagella system in A. hydrophila. To investigate the genes encoding the T3SS regulatory components exsA, exsD, exsC, and exsE were mutated and the activities of the T3SS promoters were measured in wild type and mutant backgrounds demonstrating a regulatory network. The Exs proteins were shown to interact with each other by BACTH assay and Far-Western Blot. The findings suggested a regulatory cascade in which ExsE was bound to the chaperone protein ExsC. When ExsC was free it sequestered the anti-activator ExsD thus stopping the inhibition of the T3SS master regulator ExsA allowing T3SS expression. The T3SS regulatory components were also shown to affect the expression of the lateral flagella system. The activities of the lateral flagella promoters were shown to be repressed by the absence of ExsD and ExsE, suggesting that the T3SS master regulator ExsA was a negative regulator of the lateral flagella system. PMID:27656180

  10. Structural and dynamic properties that govern the stability of an engineered fibronectin type III domain.

    PubMed

    Porebski, Benjamin T; Nickson, Adrian A; Hoke, David E; Hunter, Morag R; Zhu, Liguang; McGowan, Sheena; Webb, Geoffrey I; Buckle, Ashley M

    2015-03-01

    Consensus protein design is a rapid and reliable technique for the improvement of protein stability, which relies on the use of homologous protein sequences. To enhance the stability of a fibronectin type III (FN3) domain, consensus design was employed using an alignment of 2123 sequences. The resulting FN3 domain, FN3con, has unprecedented stability, with a melting temperature >100°C, a ΔG(D-N) of 15.5 kcal mol(-1) and a greatly reduced unfolding rate compared with wild-type. To determine the underlying molecular basis for stability, an X-ray crystal structure of FN3con was determined to 2.0 Å and compared with other FN3 domains of varying stabilities. The structure of FN3con reveals significantly increased salt bridge interactions that are cooperatively networked, and a highly optimized hydrophobic core. Molecular dynamics simulations of FN3con and comparison structures show the cooperative power of electrostatic and hydrophobic networks in improving FN3con stability. Taken together, our data reveal that FN3con stability does not result from a single mechanism, but rather the combination of several features and the removal of non-conserved, unfavorable interactions. The large number of sequences employed in this study has most likely enhanced the robustness of the consensus design, which is now possible due to the increased sequence availability in the post-genomic era. These studies increase our knowledge of the molecular mechanisms that govern stability and demonstrate the rising potential for enhancing stability via the consensus method.

  11. The Architecture of the Cytoplasmic Region of Type III Secretion Systems

    PubMed Central

    Makino, Fumiaki; Shen, Dakang; Kajimura, Naoko; Kawamoto, Akihiro; Pissaridou, Panayiota; Oswin, Henry; Pain, Maria; Murillo, Isabel; Namba, Keiichi; Blocker, Ariel J.

    2016-01-01

    Type III secretion systems (T3SSs) are essential devices in the virulence of many Gram-negative bacterial pathogens. They mediate injection of protein effectors of virulence from bacteria into eukaryotic host cells to manipulate them during infection. T3SSs involved in virulence (vT3SSs) are evolutionarily related to bacterial flagellar protein export apparatuses (fT3SSs), which are essential for flagellar assembly and cell motility. The structure of the external and transmembrane parts of both fT3SS and vT3SS is increasingly well-defined. However, the arrangement of their cytoplasmic and inner membrane export apparatuses is much less clear. Here we compare the architecture of the cytoplasmic regions of the vT3SSs of Shigella flexneri and the vT3SS and fT3SS of Salmonella enterica serovar Typhimurium at ~5 and ~4 nm resolution using electron cryotomography and subtomogram averaging. We show that the cytoplasmic regions of vT3SSs display conserved six-fold symmetric features including pods, linkers and an ATPase complex, while fT3SSs probably only display six-fold symmetry in their ATPase region. We also identify other morphological differences between vT3SSs and fT3SSs, such as relative disposition of their inner membrane-attached export platform, C-ring/pods and ATPase complex. Finally, using classification, we find that both types of apparatuses can loose elements of their cytoplasmic region, which may therefore be dynamic. PMID:27686865

  12. Structural and dynamic properties that govern the stability of an engineered fibronectin type III domain

    PubMed Central

    Porebski, Benjamin T.; Nickson, Adrian A.; Hoke, David E.; Hunter, Morag R.; Zhu, Liguang; McGowan, Sheena; Webb, Geoffrey I.; Buckle, Ashley M.

    2015-01-01

    Consensus protein design is a rapid and reliable technique for the improvement of protein stability, which relies on the use of homologous protein sequences. To enhance the stability of a fibronectin type III (FN3) domain, consensus design was employed using an alignment of 2123 sequences. The resulting FN3 domain, FN3con, has unprecedented stability, with a melting temperature >100°C, a ΔGD−N of 15.5 kcal mol−1 and a greatly reduced unfolding rate compared with wild-type. To determine the underlying molecular basis for stability, an X-ray crystal structure of FN3con was determined to 2.0 Å and compared with other FN3 domains of varying stabilities. The structure of FN3con reveals significantly increased salt bridge interactions that are cooperatively networked, and a highly optimized hydrophobic core. Molecular dynamics simulations of FN3con and comparison structures show the cooperative power of electrostatic and hydrophobic networks in improving FN3con stability. Taken together, our data reveal that FN3con stability does not result from a single mechanism, but rather the combination of several features and the removal of non-conserved, unfavorable interactions. The large number of sequences employed in this study has most likely enhanced the robustness of the consensus design, which is now possible due to the increased sequence availability in the post-genomic era. These studies increase our knowledge of the molecular mechanisms that govern stability and demonstrate the rising potential for enhancing stability via the consensus method. PMID:25691761

  13. The effect of types I and III interferons on adrenocortical cells and its possible implications for autoimmune Addison's disease.

    PubMed

    Hellesen, A; Edvardsen, K; Breivik, L; Husebye, E S; Bratland, E

    2014-06-01

    Autoimmune Addison's disease (AAD) is caused by selective destruction of the hormone-producing cells of the adrenal cortex. As yet, little is known about the potential role played by environmental factors in this process. Type I and/or type III interferons (IFNs) are signature responses to virus infections, and have also been implicated in the pathogenesis of autoimmune endocrine disorders such as type 1 diabetes and autoimmune thyroiditis. Transient development of AAD and exacerbation of established or subclinical disease, as well as the induction of autoantibodies associated with AAD, have been reported following therapeutic administration of type I IFNs. We therefore hypothesize that exposure to such IFNs could render the adrenal cortex susceptible to autoimmune attack in genetically predisposed individuals. In this study, we investigated possible immunopathological effects of type I and type III IFNs on adrenocortical cells in relation to AAD. Both types I and III IFNs exerted significant cytotoxicity on NCI-H295R adrenocortical carcinoma cells and potentiated IFN-γ- and polyinosine-polycytidylic acid [poly (I : C)]-induced chemokine secretion. Furthermore, we observed increased expression of human leucocyte antigen (HLA) class I molecules and up-regulation of 21-hydroxylase, the primary antigenic target in AAD. We propose that these combined effects could serve to initiate or aggravate an ongoing autoimmune response against the adrenal cortex in AAD.

  14. Why do the Solar Type III Burst emit the maximum of their radio energy around 1 MHz ?

    NASA Astrophysics Data System (ADS)

    Maksimovic, Milan; Krupar, Vratislav; Kontar, Eduard; Zaslavsky, Arnaud; Pascal, Louis; Reid, Hamish; Lecacheux, Alain; Bonnin, Xavier; Santolik, Ondrej; Vilmer, Nicole

    2014-05-01

    We present a statistical survey of a few hundred of Type III bursts observed from about 100 KHz up to about 400 MHz. When displayed as a function of the frequency, the radio flux exhibits a clear maximum at about 1 MHz. This property, already reported in previous studies, will be described in more details and possible explanations about its origin will be discussed.

  15. Functional and computational analysis of amino acid patterns predictive of type III secretion system substrates in Pseudomonas syringae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacterial type III secretion systems (T3SSs) deliver proteins called effectors into eukaryotic cells. Although N-terminal amino acid sequences are required for translocation, the mechanism of substrate recognition by the T3SS is unknown. Almost all actively deployed T3SS substrates in the plant path...

  16. DYNC2H1 mutations cause asphyxiating thoracic dystrophy and short rib-polydactyly syndrome, type III.

    PubMed

    Dagoneau, Nathalie; Goulet, Marie; Geneviève, David; Sznajer, Yves; Martinovic, Jelena; Smithson, Sarah; Huber, Céline; Baujat, Geneviève; Flori, Elisabeth; Tecco, Laura; Cavalcanti, Denise; Delezoide, Anne-Lise; Serre, Valérie; Le Merrer, Martine; Munnich, Arnold; Cormier-Daire, Valérie

    2009-05-01

    Jeune asphyxiating thoracic dystrophy (ATD) is an autosomal-recessive chondrodysplasia characterized by short ribs and a narrow thorax, short long bones, inconstant polydactyly, and trident acetabular roof. ATD is closely related to the short rib polydactyly syndrome (SRP) type III, which is a more severe condition characterized by early prenatal expression and lethality and variable malformations. We first excluded IFT80 in a series of 26 fetuses and children belonging to 14 families diagnosed with either ATD or SRP type III. Studying a consanguineous family from Morocco, we mapped an ATD gene to chromosome 11q14.3-q23.1 in a 20.4 Mb region and identified homozygous mutations in the cytoplasmic dynein 2 heavy chain 1 (DYNC2H1) gene in the affected children. Compound heterozygosity for DYNC2H1 mutations was also identified in four additional families. Among the five families, 3/5 were diagnosed with ATD and 2/5 included pregnancies terminated for SRP type III. DYNC2H1 is a component of a cytoplasmic dynein complex and is directly involved in the generation and maintenance of cilia. From this study, we conclude that ATD and SRP type III are variants of a single disorder belonging to the ciliopathy group.

  17. Die another day: molecular mechanisms of effector-triggered immunity elicited by type III secreted effector proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacterial pathogens inject type III secreted effector (T3SE) proteins into their hosts where they display dual roles depending on the host genotype. T3SEs promote bacterial virulence in susceptible hosts, and elicit immunity in resistant hosts. T3SEs are typically recognized when they modify a host ...

  18. Comparisons of mapped magnetic field lines with the source path of the 7 April 1995 type III solar radio burst

    NASA Astrophysics Data System (ADS)

    Li, B.; Cairns, Iver H.; Gosling, J. T.; Malaspina, D. M.; Neudegg, D.; Steward, G.; Lobzin, V. V.

    2016-07-01

    Ideally, the sources of type III solar radio bursts, which are produced mainly by flare-accelerated electron beams, trace the magnetic field lines along which the beams propagate from the Sun to interplanetary space. A recently developed 2-D approach for large-scale mapping of magnetic field lines between the Sun and Earth in the solar equatorial plane is applied to the sources of the 7 April 1995 type III radio burst imaged by Ulysses and Wind. The approach uses near-Earth solar wind data and a solar wind model with intrinsic nonradial magnetic field at the source surface of the solar wind. Quantitative agreement is found between the mapped field lines, the observed path of the radio source centroids, and the field configurations inferred from solar wind suprathermal electrons observed by Wind. Moreover, the mapped field lines are consistent with Wind not observing the in situ type III electron beam, Langmuir waves, and local radio emission for this type III event.

  19. Generation of type III solar radio bursts: the role of induced scattering of plasma waves by ions

    SciTech Connect

    Levin, B.N.; Lerner, A.M.; Rapoport, V.O.

    1984-01-01

    The plasma waves in type III solar radio-burst sources might have a spectrum which can explain why, in the quasilinear burst generation model, nonlinear scattering of the waves by ions is so weak. The agent exciting a burst would travel through the corona at velocities limited to a definite range.

  20. A comparative study of internal fixation and prosthesis replacement for radial head fractures of Mason type III.

    PubMed

    Ruan, Hong-Jiang; Fan, Cun-Yi; Liu, Jun-Jian; Zeng, Bing-Fang

    2009-02-01

    Although several treatment options for radial head fractures are available, no clear solutions exist. In this study we therefore compare open reduction and internal fixation (ORIF) with bipolar radial head prosthesis replacement in treatment of radial head fractures of Mason type III. Cement stem and bipolar radial prosthesis were used to treat 12 fresh cases and two old cases of Mason type III radial head fracture. As a control group, another eight cases of radial head type III fracture were treated with ORIF with cannulated screws and Kirschner (K) wires. The 14 patients who received radial head prosthesis replacement were followed-up for 15.9 months (range 10-27 months). According to elbow functional evaluation criteria by Broberg and Morrey, we found excellent results in nine cases, good in four, and fair in one. Mean follow-up of the eight cases in the ORIF group was 14 months (range 10-21 months), with good results in one case, fair in four, and poor in three. The result was good or excellent in 92.9% of prosthesis replacement patients and in 12.5% of ORIF patients. This difference is statistically significant (P = 0.0004; Fisher's exact test). We concluded that bipolar radial head prosthesis replacement is better than ORIF in treatment of Mason type III radial head fracture. PMID:17938924

  1. N-terminal propeptide of type III procollagen as a biomarker of anabolic response to recombinant human GH and testosterone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Context: Biomarkers that predict musculoskeletal response to anabolic therapies should expedite drug development. During collagen synthesis in soft lean tissue, N-terminal propeptide of type III procollagen (P3NP) is released into circulation. We investigated P3NP as a biomarker of lean body mass (L...

  2. Upregulation of heme oxygenase and collagen type III in the rat bladder after partial bladder outlet obstruction.

    PubMed

    Inaba, Mitsuhiko; Ukimura, Osamu; Yaoi, Takeshi; Kawauchi, Akihiro; Fushiki, Shinji; Miki, Tsuneharu

    2007-01-01

    The objective of the study was to evaluate possible changes of the gene expression and localization of the enzymes, heme oxygenase and nitric oxide synthase (NOS), with reference to increase of collagen type III in response to the partial obstruction of the bladder. Following initial obstruction, whole rat bladders were removed for real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. Real-time RT-PCR demonstrated significantly enhanced expression of HO (p < 0.01) and collagen type III (p < 0.001) gene on postoperative day 14. Enhanced expression of NOS gene was seen only on postoperative day 4 (p < 0.01). Immunohistochemistry revealed that immunoreactivity to HO-1 had much in common in neural cells and fibers, although immunoreactivity to HO-2 and iNOS was relatively weak. This study suggested gene expression of HO, especially HO-1, was more dramatically changed than NOS, and was upregulated simultaneously with increase of collagen type III after obstruction. HO systems could be involved in the pathogenesis of bladder dysfunction related to increase of collagen type III after obstruction. PMID:17406140

  3. Btc22 chaperone is required for secretion and stability of the type III secreted protein Bsp22 in Bordetella bronchiseptica.

    PubMed

    Kurushima, Jun; Kuwae, Asaomi; Abe, Akio

    2012-06-01

    The type III secretion system (T3SS) is a sophisticated protein secretion machinery that delivers bacterial virulence proteins into host cells. A needle-tip protein, Bsp22 , is one of the secreted substrates of the T3SS and plays an essential role in the full function of the T3SS in Bordetella bronchiseptica. In this study, we found that BB1618 functions as a chaperone for Bsp22 . The deletion of BB1618 resulted in a dramatic impairment of Bsp22 secretion into the culture supernatants and Bsp22 stability in the bacterial cytosol. In contrast, the secretion of other type III secreted proteins was not affected by the BB1618 mutation. Furthermore, the BB1618 mutant strain could not induce cytotoxicity and displayed the same phenotypes as the Bsp22 mutant strain. An immunoprecipitation assay demonstrated that BB1618 interacts with Bsp22 , but not with BopB and BopD . Thus, we identified BB1618 as a specific type III chaperone for Bsp22 . Therefore, we propose that BB1618 be renamed Btc22 for the Bordetella type III chaperone for Bsp22 .

  4. T3SEdb: data warehousing of virulence effectors secreted by the bacterial Type III Secretion System

    PubMed Central

    2010-01-01

    Background Effectors of Type III Secretion System (T3SS) play a pivotal role in establishing and maintaining pathogenicity in the host and therefore the identification of these effectors is important in understanding virulence. However, the effectors display high level of sequence diversity, therefore making the identification a difficult process. There is a need to collate and annotate existing effector sequences in public databases to enable systematic analyses of these sequences for development of models for screening and selection of putative novel effectors from bacterial genomes that can be validated by a smaller number of key experiments. Results Herein, we present T3SEdb http://effectors.bic.nus.edu.sg/T3SEdb, a specialized database of annotated T3SS effector (T3SE) sequences containing 1089 records from 46 bacterial species compiled from the literature and public protein databases. Procedures have been defined for i) comprehensive annotation of experimental status of effectors, ii) submission and curation review of records by users of the database, and iii) the regular update of T3SEdb existing and new records. Keyword fielded and sequence searches (BLAST, regular expression) are supported for both experimentally verified and hypothetical T3SEs. More than 171 clusters of T3SEs were detected based on sequence identity comparisons (intra-cluster difference up to ~60%). Owing to this high level of sequence diversity of T3SEs, the T3SEdb provides a large number of experimentally known effector sequences with wide species representation for creation of effector predictors. We created a reliable effector prediction tool, integrated into the database, to demonstrate the application of the database for such endeavours. Conclusions T3SEdb is the first specialised database reported for T3SS effectors, enriched with manual annotations that facilitated systematic construction of a reliable prediction model for identification of novel effectors. The T3SEdb represents a

  5. The low-high-low trend of type III radio burst starting frequencies and solar flare hard X-rays

    NASA Astrophysics Data System (ADS)

    Reid, Hamish A. S.; Vilmer, Nicole; Kontar, Eduard P.

    2014-07-01

    Aims: Using simultaneous X-ray and radio observations from solar flares, we investigate the link between the type III radio burst starting frequency and hard X-ray spectral index. For a proportion of events the relation derived between the starting height (frequency) of type III radio bursts and the electron beam velocity spectral index (deduced from X-rays) is used to infer the spatial properties (height and size) of the electron beam acceleration region. Both quantities can be related to the distance travelled before an electron beam becomes unstable to Langmuir waves. Methods: To obtain a list of suitable events we considered the RHESSI catalogue of X-ray flares and the Phoenix 2 catalogue of type III radio bursts. From the 200 events that showed both type III and X-ray signatures, we selected 30 events which had simultaneous emission in both wavelengths, good signal to noise in the X-ray domain and >20 s duration. Results: We find that >50% of the selected events show a good correlation between the starting frequencies of the groups of type III bursts and the hard X-ray spectral indices. A low-high-low trend for the starting frequency of type III bursts is frequently observed. Assuming a background electron density model and the thick target approximation for X-ray observations, this leads to a correlation between starting heights of the type III emission and the beam electron spectral index. Using this correlation we infer the altitude and vertical extents of the flare acceleration regions. We find heights from 183 Mm down to 25 Mm while the sizes range from 13 Mm to 2 Mm. These values agree with previous work that places an extended flare acceleration region high in the corona. We also analyse the assumptions that are required to obtain our estimates and explore possible extensions to our assumed model. We discuss these results with respect to the acceleration heights and sizes derived from X-ray observations alone. Appendices are available in electronic form

  6. Spatiotemporal Patterns of a Predator-Prey System with an Allee Effect and Holling Type III Functional Response

    NASA Astrophysics Data System (ADS)

    Li, Yuanyuan; Wang, Jinfeng

    A diffusive Gause type predator-prey system with Allee effect in prey growth and Holling type III response subject to Neumann boundary conditions is investigated. Existence of nonconstant positive steady state solutions is proved by Leray-Schauder degree theory and bifurcation theory. Global stability of the positive equilibrium of the system is also investigated. Moreover, bifurcations of spatially homogeneous and nonhomogeneous periodic solutions are analyzed. Our rigorous results justify some recent ecological observations.

  7. Influence of Term of Exposure to High-Fat Diet-Induced Obesity on Myocardial Collagen Type I and III

    PubMed Central

    da Silva, Danielle Cristina Tomaz; Lima-Leopoldo, Ana Paula; Leopoldo, André Soares; de Campos, Dijon Henrique Salomé; do Nascimento, André Ferreira; de Oliveira, Sílvio Assis; Padovani, Carlos Roberto; Cicogna, Antonio Carlos

    2014-01-01

    Background Obesity is a risk factor for many medical complications; medical research has shown that hemodynamic, morphological and functional abnormalities are correlated with the duration and severity of obesity. Objective Present study determined the influence of term of exposure to high-fat diet-induced obesity on myocardial collagen type I and III. Methods Thirty-day-old male Wistar rats were randomly distributed into two groups: a control (C) group fed a standard rat chow and an obese (Ob) group alternately fed one of four palatable high-fat diets. Each diet was changed daily, and the rats were maintained on their respective diets for 15 (C15 and Ob15) and 30 (C30 and Ob30) consecutive weeks. Obesity was determined by adiposity index. Results The Ob15 group was similar to the C15 group regarding the expression of myocardial collagen type I; however, expression in the Ob30 group was less than C30 group. The time of exposure to obesity was associated with a reduction in collagen type I in Ob30 when compared with Ob15. Obesity did not affect collagen type III expression. Conclusion This study showed that the time of exposure to obesity for 30 weeks induced by unsaturated high-fat diet caused a reduction in myocardial collagen type I expression in the obese rats. However, no effect was seen on myocardial collagen type III expression. PMID:24676371

  8. Diagnosing the Source Region of a Solar Burst on 26 September 2011 by Using Microwave Type-III Pairs

    NASA Astrophysics Data System (ADS)

    Tan, B. L.; Karlický, M.; Mészárosová, H.; Kashapova, L.; Huang, J.; Yan, Y.; Kontar, E. P.

    2016-09-01

    We report a peculiar and interesting train of microwave Type-III pair bursts in the impulsive rising phase of a solar flare on 26 September 2011. The observations include radio spectrometers at frequencies of 0.80 - 2.00 GHz from the Ondřejov radiospectrograph in the Czech Republic (ORSC), hard X-ray from the Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) and Gamma-Ray Burst Monitor onboard the Fermi Space Telescope (Fermi/GRB), EUV images from the Sun Watcher using APS detectors and image Processing instrument onboard the Project for Onboard Autonomy 2 (SWAP/PROBA2), and magnetograms from the Helioseismic and Magnetic Imager onboard the Solar Dynamic Observatory (SDO/HMI). By using a recently developed method (Tan et al., Res. Astron. Astrophys. 16, 82, 2016a), we diagnosed the plasma density, temperature, plasma- β, magnetic field near the source region, the energy of energetic electrons, and the distance between the acceleration region and the emission start sites of Type-III bursts. From the diagnostics, we find that i) The plasma density, temperature, magnetic field, and the distance between the acceleration region and the emission start sites have almost no obvious variations during the period of Type-III pair trains, while the energy of electrons has an obvious peak value that is consistent with the hard X-ray emission. ii) The plasma- β is much higher than unity, showing a highly dynamic process near the emission start site of Type-III bursts. iii) Although the reversed-slope Type-III branches drift more slowly by one order of magnitude than that of the normal Type-IIIs, the related descending and ascending electrons still could have energy of the same order of magnitude. These facts indicate that both the ascending and descending electrons are possibly accelerated by a similar mechanism and in a small source region. These diagnostics can help us to understand the physics in the source region of solar bursts.

  9. Diagnosing the Source Region of a Solar Burst on 26 September 2011 by Using Microwave Type-III Pairs

    NASA Astrophysics Data System (ADS)

    Tan, B. L.; Karlický, M.; Mészárosová, H.; Kashapova, L.; Huang, J.; Yan, Y.; Kontar, E. P.

    2016-10-01

    We report a peculiar and interesting train of microwave Type-III pair bursts in the impulsive rising phase of a solar flare on 26 September 2011. The observations include radio spectrometers at frequencies of 0.80 - 2.00 GHz from the Ondřejov radiospectrograph in the Czech Republic (ORSC), hard X-ray from the Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) and Gamma-Ray Burst Monitor onboard the Fermi Space Telescope ( Fermi/GRB), EUV images from the Sun Watcher using APS detectors and image Processing instrument onboard the Project for Onboard Autonomy 2 (SWAP/PROBA2), and magnetograms from the Helioseismic and Magnetic Imager onboard the Solar Dynamic Observatory (SDO/HMI). By using a recently developed method (Tan et al., Res. Astron. Astrophys. 16, 82, 2016a), we diagnosed the plasma density, temperature, plasma-β, magnetic field near the source region, the energy of energetic electrons, and the distance between the acceleration region and the emission start sites of Type-III bursts. From the diagnostics, we find that i) The plasma density, temperature, magnetic field, and the distance between the acceleration region and the emission start sites have almost no obvious variations during the period of Type-III pair trains, while the energy of electrons has an obvious peak value that is consistent with the hard X-ray emission. ii) The plasma-β is much higher than unity, showing a highly dynamic process near the emission start site of Type-III bursts. iii) Although the reversed-slope Type-III branches drift more slowly by one order of magnitude than that of the normal Type-IIIs, the related descending and ascending electrons still could have energy of the same order of magnitude. These facts indicate that both the ascending and descending electrons are possibly accelerated by a similar mechanism and in a small source region. These diagnostics can help us to understand the physics in the source region of solar bursts.

  10. Gaucher disease--Norrbottnian type (III). Neuropaediatric and neurobiological aspects of clinical patterns and treatment.

    PubMed

    Erikson, A

    1986-01-01

    This investigation was undertaken to study the clinical manifestations, development and course of the Norrbottnian type of Gaucher disease--a type III variant--with emphasis on central nervous system symptomatology and function, to correlate clinical signs with laboratory, neuropathological and biochemical findings, to evaluate effects of splenectomy on the course and severity of the disease and to investigate the effect of bone marrow transplantation. Clinical methods applied were neuropaediatric follow-up examinations, psychometric tests and motor age tests. Conventional neurophysiological, haematological and clinico-chemical methods were used. The investigation comprised 22 patients, 10 girls and 12 boys, in all of whom the clinical diagnosis was confirmed by enzymatic tests. The median age at diagnosis was 1.9 years. The clinical pattern at diagnosis was usually that of an alert child with normal intelligence, short stature, splenomegaly, a tendency to bleeding and ocular manifestations. The course was slowly progressive but varied considerably between patients. The median age at death in a representative group of patients was 11.8 years. Early motor development was delayed in the lower limbs but normal in the upper. Eight patients later developed ataxia and six patients signs of mild spastic paraparesis which usually appeared many years after splenectomy. IQ tended to decrease with age. Early splenectomy resulted in lower IQ scores than late splenectomy. With progression of the disease, EEG abnormalities became increasingly frequent, more markedly among splenectomized patients. Thirteen patients had abducens nerve weakness and ten had age dependent abnormalities of horizontal gaze. Retinal infiltrates were characteristic, mainly among splenectomized patients. At, autopsy, Gaucher cell accumulations were found in the adventitia of brain venules, most frequently in cerebral and cerebellar subcortical white matter. Intraneuronal storage of glucosylceramide was

  11. Coronal extension of flaring region magnetic fields inferred from high-resolution microwave and type III burst observations

    SciTech Connect

    Lantos, P.; Pick, M.; Kundu, M.R.

    1984-08-15

    Observations of three solar radio bursts, obtained with the Very Large Array of the National Radio Astronomy Observatory at 6 cm wavelength, have been combined with meter observationss from the Mark III Nancay Radioheliograph. There is a good correlation between solar activity observed at the two wavelength domains. A small change by about 10'' in the centimetric burst location corresponds to a large change, by about 0.5 R/sub sun/, in the related metric type III burst location. This indicates discrete injection/acceleration regions and the presence of very divergent magnetic fields.

  12. T346Hunter: a novel web-based tool for the prediction of type III, type IV and type VI secretion systems in bacterial genomes.

    PubMed

    Martínez-García, Pedro Manuel; Ramos, Cayo; Rodríguez-Palenzuela, Pablo

    2015-01-01

    T346Hunter (Type Three, Four and Six secretion system Hunter) is a web-based tool for the identification and localisation of type III, type IV and type VI secretion systems (T3SS, T4SS and T6SS, respectively) clusters in bacterial genomes. Non-flagellar T3SS (NF-T3SS) and T6SS are complex molecular machines that deliver effector proteins from bacterial cells into the environment or into other eukaryotic or prokaryotic cells, with significant implications for pathogenesis of the strains encoding them. Meanwhile, T4SS is a more functionally diverse system, which is involved in not only effector translocation but also conjugation and DNA uptake/release. Development of control strategies against bacterial-mediated diseases requires genomic identification of the virulence arsenal of pathogenic bacteria, with T3SS, T4SS and T6SS being major determinants in this regard. Therefore, computational methods for systematic identification of these specialised machines are of particular interest. With the aim of facilitating this task, T346Hunter provides a user-friendly web-based tool for the prediction of T3SS, T4SS and T6SS clusters in newly sequenced bacterial genomes. After inspection of the available scientific literature, we constructed a database of hidden Markov model (HMM) protein profiles and sequences representing the various components of T3SS, T4SS and T6SS. T346Hunter performs searches of such a database against user-supplied bacterial sequences and localises enriched regions in any of these three types of secretion systems. Moreover, through the T346Hunter server, users can visualise the predicted clusters obtained for approximately 1700 bacterial chromosomes and plasmids. T346Hunter offers great help to researchers in advancing their understanding of the biological mechanisms in which these sophisticated molecular machines are involved. T346Hunter is freely available at http://bacterial-virulence-factors.cbgp.upm.es/T346Hunter.

  13. The Xanthomonas campestris Type III Effector XopJ Proteolytically Degrades Proteasome Subunit RPT61[OPEN

    PubMed Central

    2015-01-01

    Many animal and plant pathogenic bacteria inject type III effector (T3E) proteins into their eukaryotic host cells to suppress immunity. The Yersinia outer protein J (YopJ) family of T3Es is a widely distributed family of effector proteins found in both animal and plant pathogens, and its members are highly diversified in virulence functions. Some members have been shown to possess acetyltransferase activity; however, whether this is a general feature of YopJ family T3Es is currently unknown. The T3E Xanthomonas outer protein J (XopJ), a YopJ family effector from the plant pathogen Xanthomonas campestris pv vesicatoria, interacts with the proteasomal subunit Regulatory Particle AAA-ATPase6 (RPT6) in planta to suppress proteasome activity, resulting in the inhibition of salicylic acid-related immune responses. Here, we show that XopJ has protease activity to specifically degrade RPT6, leading to reduced proteasome activity in the cytoplasm as well as in the nucleus. Proteolytic degradation of RPT6 was dependent on the localization of XopJ to the plasma membrane as well as on its catalytic triad. Mutation of the Walker B motif of RPT6 prevented XopJ-mediated degradation of the protein but not XopJ interaction. This indicates that the interaction of RPT6 with XopJ is dependent on the ATP-binding activity of RPT6, but proteolytic cleavage additionally requires its ATPase activity. Inhibition of the proteasome impairs the proteasomal turnover of Nonexpressor of Pathogenesis-Related1 (NPR1), the master regulator of salicylic acid responses, leading to the accumulation of ubiquitinated NPR1, which likely interferes with the full induction of NPR1 target genes. Our results show that YopJ family T3Es are not only highly diversified in virulence function but also appear to possess different biochemical activities. PMID:25739698

  14. A type III effector antagonises death receptor signalling during bacterial