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Sample records for intact polysaccharide capsule

  1. Campylobacter Polysaccharide Capsules: Virulence and Vaccines

    PubMed Central

    Guerry, Patricia; Poly, Frédéric; Riddle, Mark; Maue, Alexander C.; Chen, Yu-Han; Monteiro, Mario A.

    2012-01-01

    Campylobacter jejuni remains a major cause of bacterial diarrhea worldwide and is associated with numerous sequelae, including Guillain Barré Syndrome, inflammatory bowel disease, reactive arthritis, and irritable bowel syndrome. C. jejuni is unusual for an intestinal pathogen in its ability to coat its surface with a polysaccharide capsule (CPS). These capsular polysaccharides vary in sugar composition and linkage, especially those involving heptoses of unusual configuration and O-methyl phosphoramidate linkages. This structural diversity is consistent with CPS being the major serodeterminant of the Penner scheme, of which there are 47 C. jejuni serotypes. Both CPS expression and expression of modifications are subject to phase variation by slip strand mismatch repair. Although capsules are virulence factors for other pathogens, the role of CPS in C. jejuni disease has not been well defined beyond descriptive studies demonstrating a role in serum resistance and for diarrhea in a ferret model of disease. However, perhaps the most compelling evidence for a role in pathogenesis are data that CPS conjugate vaccines protect against diarrheal disease in non-human primates. A CPS conjugate vaccine approach against this pathogen is intriguing, but several questions need to be addressed, including the valency of CPS types required for an effective vaccine. There have been numerous studies of prevalence of CPS serotypes in the developed world, but few studies from developing countries where the disease incidence is higher. The complexity and cost of Penner serotyping has limited its usefulness, and a recently developed multiplex PCR method for determination of capsule type offers the potential of a more rapid and affordable method. Comparative studies have shown a strong correlation of the two methods and studies are beginning to ascertain CPS-type distribution worldwide, as well as examination of correlation of severity of illness with specific CPS types. PMID:22919599

  2. Capsule of Cryptococcus neoformans grows by enlargement of polysaccharide molecules.

    PubMed

    Frases, Susana; Pontes, Bruno; Nimrichter, Leonardo; Viana, Nathan B; Rodrigues, Marcio L; Casadevall, Arturo

    2009-01-27

    The human pathogenic fungus Cryptococcus neoformans has a distinctive polysaccharide (PS) capsule that enlarges during infection. The capsule is essential for virulence, but the mechanism for capsular growth is unknown. In the present study, we used dynamic light scattering (LS) analysis of capsular PS and optical tweezers (OT) to explore the architecture of the capsule. Analysis of capsular PS from cells with small and large capsules by dynamic LS revealed a linear correlation between PS effective diameter and microscopic capsular diameter. This result implied that capsule growth was achieved by the addition of molecules with larger effective diameter, such that some molecules can span the entire diameter of the capsule. Measurement of polystyrene bead penetration of C. neoformans capsules by using OT techniques revealed that the outer regions were penetrable, but not the inner regions. Our results provide a mechanism for capsular enlargement based on the axial lengthening of PS molecules and suggest a model for the architecture of a eukaryotic microbial capsule.

  3. Characterization of the Kingella kingae Polysaccharide Capsule and Exopolysaccharide

    PubMed Central

    Starr, Kimberly F.; Porsch, Eric A.; Heiss, Christian; Black, Ian; Azadi, Parastoo; St. Geme, Joseph W.

    2013-01-01

    Recent evidence indicates that Kingella kingae produces a polysaccharide capsule. In an effort to determine the composition and structure of this polysaccharide capsule, in the current study we purified capsular material from the surface of K. kingae strain 269–492 variant KK01 using acidic conditions to release the capsule and a series of steps to remove DNA, RNA, and protein. Analysis of the resulting material by gas chromatography and mass spectrometry revealed N-acetyl galactosamine (GalNAc), 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo), and galactose (Gal). Further analysis by NMR demonstrated two distinct polysaccharides, one consisting of GalNAc and Kdo with the structure →3)-β-GalpNAc-(1→5)-β-Kdop-(2→ and the other containing galactose alone with the structure →5)-β-Galf-(1→. Disruption of the ctrA gene required for surface localization of the K. kingae polysaccharide capsule resulted in elimination of GalNAc and Kdo but had no effect on the presence of Gal in bacterial surface extracts. In contrast, deletion of the pamABCDE locus involved in production of a reported galactan exopolysaccharide eliminated Gal but had no effect on the presence of GalNAc and Kdo in surface extracts. Disruption of ctrA and deletion of pamABCDE resulted in a loss of all carbohydrates in surface extracts. These results establish that K. kingae strain KK01 produces a polysaccharide capsule with the structure →3)-β-GalpNAc-(1→5)-β-Kdop-(2→ and a separate exopolysaccharide with the structure →5)-β-Galf-(1→. The polysaccharide capsule and the exopolysaccharide require distinct genetic loci for surface localization. PMID:24098695

  4. Characterization of bacterial polysaccharide capsules and detection in the presence of deliquescent water by atomic force microscopy.

    PubMed

    Su, Hai-Nan; Chen, Zhi-Hua; Liu, Sheng-Bo; Qiao, Li-Ping; Chen, Xiu-Lan; He, Hai-Lun; Zhao, Xian; Zhou, Bai-Cheng; Zhang, Yu-Zhong

    2012-05-01

    We detected polysaccharide capsules from Zunongwangia profunda SM-A87 with atomic force microscopy (AFM). The molecular organization of the capsules at the single-polysaccharide-chain level was reported. Furthermore, we found that with ScanAsyst mode the polysaccharide capsules could be detected even in the presence of deliquescent water covering the capsule.

  5. Characterization of Bacterial Polysaccharide Capsules and Detection in the Presence of Deliquescent Water by Atomic Force Microscopy

    PubMed Central

    Su, Hai-Nan; Chen, Zhi-Hua; Liu, Sheng-Bo; Qiao, Li-Ping; Chen, Xiu-Lan; He, Hai-Lun; Zhao, Xian; Zhou, Bai-Cheng

    2012-01-01

    We detected polysaccharide capsules from Zunongwangia profunda SM-A87 with atomic force microscopy (AFM). The molecular organization of the capsules at the single-polysaccharide-chain level was reported. Furthermore, we found that with ScanAsyst mode the polysaccharide capsules could be detected even in the presence of deliquescent water covering the capsule. PMID:22344657

  6. A Subset of Polysaccharide Capsules in the Human Symbiont Bacteroides thetaiotaomicron Promote Increased Competitive Fitness in the Mouse Gut.

    PubMed

    Porter, Nathan T; Canales, Pablo; Peterson, Daniel A; Martens, Eric C

    2017-09-27

    Capsular polysaccharides (CPSs) play multiple roles in protecting bacteria from host and environmental factors, and many commensal bacteria can produce multiple capsule types. To better understand the roles of different CPSs in competitive intestinal colonization, we individually expressed the eight different capsules of the human gut symbiont Bacteroides thetaiotaomicron. Certain CPSs were most advantageous in vivo, and increased anti-CPS immunoglobulin A correlated with increased fitness of a strain expressing one particular capsule, CPS5, suggesting that it promotes avoidance of adaptive immunity. A strain with the ability to switch between multiple capsules was more competitive than those expressing any single capsule except CPS5. After antibiotic perturbation, only the wild-type, capsule-switching strain remained in the gut, shifting to prominent expression of CPS5 only in mice with intact adaptive immunity. These data suggest that different capsules equip mutualistic gut bacteria with the ability to thrive in various niches, including those influenced by immune responses and antibiotic perturbations. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Perforation forces of the intact porcine anterior lens capsule.

    PubMed

    Ullrich, Franziska; Lussi, Jonas; Felekis, Dimitrios; Michels, Stephan; Petruska, Andrew J; Nelson, Bradley J

    2016-09-01

    During the first step of cataract surgery, the lens capsule is perforated and a circular hole is created with a sharp instrument, a procedure called capsulorhexis. To develop automated systems that can assist ophthalmologists during capsulorhexis, the forces required must be quantified. This study investigates perforation forces of the central anterior lens capsule in porcine eyes, which are used as a conservative model for the human eye. A micro-mechanical characterisation method is presented that measures capsular bag perforation forces with a high precision positioning and high-resolution force sensing system. The force during perforation of the anterior lens capsule was measured with various sized needles and indentation speeds and is found to be 15-35mN. A bio-mechanical model is identified that describes an exponential correlation between indentation force and depth, indicating strain hardening behaviour of the porcine anterior lens capsule.

  8. Sono-assembly of highly biocompatible polysaccharide capsules for hydrophobic drug delivery.

    PubMed

    Wang, Hongqiang; Yan, Xuehai; Li, Guo Liang; Pilz-Allen, Christine; Möhwald, Helmuth; Shchukin, Dmitry

    2014-06-01

    Cells like sugar. General synthesis and potential of intracellular hydrophobic drug delivery of single-component polysaccharide capsules are pursued. The capsules can be generally assembled through hydrogen bonding networks but show striking shell robustness. The evidenced cell internalization, stimuli-responsiveness to local pH changes and high biocompatibilities of the capsules specifically favor their potential intracellular drug delivery. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Polysaccharide capsule of Escherichia coli: microscope study of its size, structure, and sites of synthesis.

    PubMed Central

    Bayer, M E; Thurow, H

    1977-01-01

    This report describes the structure, size, and shape of the uncollapsed polysaccharide capsule of Escherichia coli strain Bi 161/42 [O9:K29(A):H-], its ultrastructural preservation as well as the filamentous components of the isolated capsular material. In a temperature-sensitive mutant, sites were localized at which capsular polysaccharide is "exported" to the cell surface. The highly hydrated capsule of the wild-type cells was visible in the uncollapsed state after freeze-etching, whereas dehydration in greater than or equal to 50% acetone or alcohol caused the capsule to collapse into thick bundles. This was prevented by pretreatment of the cell with capsule-specific immunoglobulin G; the capsule appeared as a homogeneous layer of 250- to 300-nm thickness. The structural preservation depended on the concentration of the anti-capsular immunoglobulin G. Temperature-sensitive mutants, unable to produce capsular antigen at elevated temperatures, showed, 10 to 15 min after shift down to permissive temperature, polysaccharide strands with K29 specificity appearing at the cell surface at roughly 20 sites per cell; concomitantly, capsule-directed antibody started to agglutinate the bacteria. The sites at which the new antigen emerged were found in random distribution over the entire surface of the organism. Spreading of purified polysaccharide was achieved on air-water interfaces; after subsequent shadow casting with heavy metal, filamentous elements were observed with a smallest class of filaments measuring 250 nm in length and 3 to 6 nm in width. At one end these fibers revealed a knoblike structure of about 10-nm diameter. The slimelike polysaccharides from mutants produced filamentous bundles of greater than 100-microns length, with antigenic and phage-receptor properties indistinguishable from those of the wild-type K29 capsule antigen. Images PMID:400798

  10. Bioavailability of lansoprazole granules administered in juice or soft food compared with the intact capsule formulation.

    PubMed

    Chun, Alexander H C; Erdman, Keith; Chiu, Yi-Lin; Pilmer, Betsy L; Achari, Ramanuj; Cavanaugh, John H

    2002-08-01

    The ability to administer the contents of an encapsulated-dose formulation in liquids or soft foods without compromising drug bioavailability is highly desirable for patients who are unable to swallow or have difficulty swallowing. The purpose of this study was to compare the bioavailability of lansoprazole granules administered in 2 types of juice and a soft food with that of the intact capsule administered with water. Healthy adult volunteers were eligible for this single-center, Phase I, single-dose, randomized, open-label, 4-period crossover study. Subjects received the enteric-coated granular contents of a 30-mg lansoprazole capsule in 3 test regimens (in 180 mL of orange juice, 180 mL of tomato juice, or 1 tablespoon of strained pears, each followed by 180 mL of water) and 1 reference regimen (the 30-mg intact capsule with 180 mL of water). The regimens were rotated at > or = 6-day intervals so that each subject received all 4 regimens. Blood samples for pharmacokinetic analyses were obtained during the 12 hours after each regimen. Twenty healthy adult volunteers (10 men, 10 women; mean age, 36 years [range, 19-53 years]) completed this study. Bioavailability of the 3 test regimens was assessed using the two 1-sided tests procedure for mean maximum plasma concentration and area under the plasma concentration-time curve (AUC) from time 0 through the last measurable concentration and AUC from time 0 to infinity. These results were compared with that of the intact capsule. This comparison indicated that the 90% CIs for all 3 test regimens were within the acceptable bioequivalence range of 0.80 to 1.25. Lansoprazole was well tolerated, with most of the adverse events being mild. Headache was the most frequently reported adverse event. The results of this study indicate that the bioavailability of lansoprazole granules, when administered in orange juice, tomato juice, or a small amount of strained pears, was similar to that of the intact capsule in these healthy

  11. [Influence of nutrient medium composition on the production of capsule polysaccharide by Streptococcus pneumonia 19A serotype].

    PubMed

    Grishchenko, N V; Tokarskaia, M M; Kalina, N G; Elkina, S I; Golovinskaia, O V; Iastrebova, N E; Ledov, V A

    2012-01-01

    Evaluate accumulation of capsule polysaccharide by Streptococcus pneumoniae 19A strain in semisynthetic nutrient medium including various amino acid sources. Comparative evaluation of the production of capsule polysaccharide by the strain belonging to one of the most widespread S. pneumoniae serotype (19A) was performed by using rocket immunoelectrophoresis. The bacteria were cultivated in semisynthetic liquid nutrient media of varying composition. Among 4 sources of nitrogen (aminopeptide, acid and pancreatic hydrolysate of casein, soy peptone) added to salt nutrient medium supplemented with glucose and vitamins, casein and soy peptone were shown to promote the maximum synthesis of capsule polysaccharide independently of the cultivation time. Supplementation of the medium with sulfates of iron, zinc and manganese, as well as pH decrease to acid values significantly reduced the level of capsule polysaccharide in the culture liquid. The maximum growth of bacteria was observed at 11 hours after the start of cultivation in a 10 L volume fermenter in semisynthetic nutrient medium with soy peptone. Accumulation of capsule polysaccharide in the culture liquid continued to the end of the observation period (24 hours) and by the end of the process reached 193 mcg/ml. Further study of influence of vitamins, carbohydrates, CO2 concentration on the synthesis of high molecular capsule polysaccharide by bacteria belonging to various pneumococcus serotypes is reasonable.

  12. Linkage of genes essential for synthesis of a polysaccharide capsule in Sphingomonas strain S88.

    PubMed

    Yamazaki, M; Thorne, L; Mikolajczak, M; Armentrout, R W; Pollock, T J

    1996-05-01

    Several structurally related capsular polysaccharides that are secreted by members of the genus Sphingomonas are being developed as aqueous rheological control agents for diverse industrial and food applications. They include gellan (S-60), welan (S-130), rhamsan (S-194), S-657, S-88, S-198, S-7, and NW-11. We refer to these polysaccharides as sphingans, after the genus name. This paper characterizes the first gene cluster isolated from a Sphingomonas species (S88) that is required for capsule synthesis. Overlapping DNA segments which spanned about 50 kbp of S88 DNA restored the synthesis of sphingan S-88 in capsule-negative mutants. The mutations were mapped into functional complementation groups, and the contiguous nucleotide sequence for the 29-kbp cluster was determined. The genetic complementation map and the DNA sequences were interpreted as an extended multicistronic locus containing genes essential for the assembly and secretion of polysaccharide S-88. Many of the deduced amino acid sequences were similar to gene products from other polysaccharide-secreting bacteria such as Rhizobium meliloti (succinoglycan), Xanthomonas campestris (xanthan gum), and Salmonella enterica (O antigen). The S88 locus contained a four-gene operon for the biosynthesis of dTDP-L-rhamnose, an essential precursor for the sphingans. Unexpectedly, there were also two genes for secretion of a lytic or toxin-like protein nested within the polysaccharide cluster. The conservation and linkage of genes that code for a defensive capsule and genes for secretion of an offensive lysin or toxin suggest a heretofore unknown pathogenic life history for Sphingomonas strain S88.

  13. Linkage of genes essential for synthesis of a polysaccharide capsule in Sphingomonas strain S88.

    PubMed Central

    Yamazaki, M; Thorne, L; Mikolajczak, M; Armentrout, R W; Pollock, T J

    1996-01-01

    Several structurally related capsular polysaccharides that are secreted by members of the genus Sphingomonas are being developed as aqueous rheological control agents for diverse industrial and food applications. They include gellan (S-60), welan (S-130), rhamsan (S-194), S-657, S-88, S-198, S-7, and NW-11. We refer to these polysaccharides as sphingans, after the genus name. This paper characterizes the first gene cluster isolated from a Sphingomonas species (S88) that is required for capsule synthesis. Overlapping DNA segments which spanned about 50 kbp of S88 DNA restored the synthesis of sphingan S-88 in capsule-negative mutants. The mutations were mapped into functional complementation groups, and the contiguous nucleotide sequence for the 29-kbp cluster was determined. The genetic complementation map and the DNA sequences were interpreted as an extended multicistronic locus containing genes essential for the assembly and secretion of polysaccharide S-88. Many of the deduced amino acid sequences were similar to gene products from other polysaccharide-secreting bacteria such as Rhizobium meliloti (succinoglycan), Xanthomonas campestris (xanthan gum), and Salmonella enterica (O antigen). The S88 locus contained a four-gene operon for the biosynthesis of dTDP-L-rhamnose, an essential precursor for the sphingans. Unexpectedly, there were also two genes for secretion of a lytic or toxin-like protein nested within the polysaccharide cluster. The conservation and linkage of genes that code for a defensive capsule and genes for secretion of an offensive lysin or toxin suggest a heretofore unknown pathogenic life history for Sphingomonas strain S88. PMID:8626338

  14. Recombination in Streptococcus pneumoniae Lineages Increase with Carriage Duration and Size of the Polysaccharide Capsule

    PubMed Central

    Andam, Cheryl P.; Harris, Simon R.; Cornick, Jennifer E.; Yang, Marie; Bricio-Moreno, Laura; Kamng’ona, Arox W.; French, Neil; Heyderman, Robert S.; Kadioglu, Aras; Everett, Dean B.; Bentley, Stephen D.

    2016-01-01

    ABSTRACT Streptococcus pneumoniae causes a high burden of invasive pneumococcal disease (IPD) globally, especially in children from resource-poor settings. Like many bacteria, the pneumococcus can import DNA from other strains or even species by transformation and homologous recombination, which has allowed the pneumococcus to evade clinical interventions such as antibiotics and pneumococcal conjugate vaccines (PCVs). Pneumococci are enclosed in a complex polysaccharide capsule that determines the serotype; the capsule varies in size and is associated with properties including carriage prevalence and virulence. We determined and quantified the association between capsule and recombination events using genomic data from a diverse collection of serotypes sampled in Malawi. We determined both the amount of variation introduced by recombination relative to mutation (the relative rate) and how many individual recombination events occur per isolate (the frequency). Using univariate analyses, we found an association between both recombination measures and multiple factors associated with the capsule, including duration and prevalence of carriage. Because many capsular factors are correlated, we used multivariate analysis to correct for collinearity. Capsule size and carriage duration remained positively associated with recombination, although with a reduced P value, and this effect may be mediated through some unassayed additional property associated with larger capsules. This work describes an important impact of serotype on recombination that has been previously overlooked. While the details of how this effect is achieved remain to be determined, it may have important consequences for the serotype-specific response to vaccines and other interventions. PMID:27677790

  15. Kingella kingae Expresses Four Structurally Distinct Polysaccharide Capsules That Differ in Their Correlation with Invasive Disease

    PubMed Central

    Porsch, Eric A.; Seed, Patrick C.; Heiss, Christian; Naran, Radnaa; Amit, Uri; Yagupsky, Pablo; Azadi, Parastoo; St. Geme, Joseph W.

    2016-01-01

    Kingella kingae is an encapsulated gram-negative organism that is a common cause of osteoarticular infections in young children. In earlier work, we identified a glycosyltransferase gene called csaA that is necessary for synthesis of the [3)-β-GalpNAc-(1→5)-β-Kdop-(2→] polysaccharide capsule (type a) in K. kingae strain 269–492. In the current study, we analyzed a large collection of invasive and carrier isolates from Israel and found that csaA was present in only 47% of the isolates. Further examination of this collection using primers based on the sequence that flanks csaA revealed three additional gene clusters (designated the csb, csc, and csd loci), all encoding predicted glycosyltransferases. The csb locus contains the csbA, csbB, and csbC genes and is associated with a capsule that is a polymer of [6)-α-GlcpNAc-(1→5)-β-(8-OAc)Kdop-(2→] (type b). The csc locus contains the cscA, cscB, and cscC genes and is associated with a capsule that is a polymer of [3)-β-Ribf-(1→2)-β-Ribf-(1→2)-β-Ribf-(1→4)-β-Kdop-(2→] (type c). The csd locus contains the csdA, csdB, and csdC genes and is associated with a capsule that is a polymer of [P-(O→3)[β-Galp-(1→4)]-β-GlcpNAc-(1→3)-α-GlcpNAc-1-] (type d). Introduction of the csa, csb, csc, and csd loci into strain KK01Δcsa, a strain 269–492 derivative that lacks the native csaA gene, was sufficient to produce the type a capsule, type b capsule, type c capsule, and type d capsule, respectively, indicating that these loci are solely responsible for determining capsule type in K. kingae. Further analysis demonstrated that 96% of the invasive isolates express either the type a or type b capsule and that a disproportionate percentage of carrier isolates express the type c or type d capsule. These results establish that there are at least four structurally distinct K. kingae capsule types and suggest that capsule type plays an important role in promoting K. kingae invasive disease. PMID:27760194

  16. Kingella kingae expresses four structurally distinct polysaccharide capsules that differ in their correlation with invasive disease

    DOE PAGES

    Starr, Kimberly F.; Porsch, Eric A.; Seed, Patrick C.; ...

    2016-10-19

    Kingella kingae is an encapsulated gram-negative organism that is a common cause of osteoarticular infections in young children. In earlier work, we identified a glycosyltransferase gene called csaA that is necessary for synthesis of the [3)-β-GalpNAc-(1→5)-β-Kdop-(2→] polysaccharide capsule (type a) in K. kingae strain 269–492. In the current study, we analyzed a large collection of invasive and carrier isolates from Israel and found that csaA was present in only 47% of the isolates. Further examination of this collection using primers based on the sequence that flanks csaA revealed three additional gene clusters (designated the csb, csc, and csd loci), allmore » encoding predicted glycosyltransferases. The csb locus contains the csbA, csbB, and csbC genes and is associated with a capsule that is a polymer of [6)-α-GlcpNAc-(1→5)-β-(8-OAc)Kdop-(2→] (type b). The csc locus contains the cscA, cscB, and cscC genes and is associated with a capsule that is a polymer of [3)-β-Ribf-(1→2)-β-Ribf-(1→2)-β-Ribf-(1→4)-β-Kdop-(2→] (type c). The csd locus contains the csdA, csdB, and csdC genes and is associated with a capsule that is a polymer of [P-(O→3)[β-Galp-(1→4)]-β-GlcpNAc-(1→3)-α-GlcpNAc-1-] (type d). Introduction of the csa, csb, csc, and csd loci into strain KK01Δcsa, a strain 269–492 derivative that lacks the native csaA gene, was sufficient to produce the type a capsule, type b capsule, type c capsule, and type d capsule, respectively, indicating that these loci are solely responsible for determining capsule type in K. kingae. Further analysis demonstrated that 96% of the invasive isolates express either the type a or type b capsule and that a disproportionate percentage of carrier isolates express the type c or type d capsule. Lastly, these results establish that there are at least four structurally distinct K. kingae capsule types and suggest that capsule type plays an important role in promoting K. kingae invasive disease« less

  17. Unusual galactofuranose modification of a capsule polysaccharide in the pathogenic yeast Cryptococcus neoformans.

    PubMed

    Heiss, Christian; Skowyra, Michael L; Liu, Hong; Klutts, J Stacey; Wang, Zhirui; Williams, Matthew; Srikanta, Deepa; Beverley, Stephen M; Azadi, Parastoo; Doering, Tamara L

    2013-04-19

    Galactofuranose (Galf) is the five-membered ring form of galactose. Although it is absent from mammalian glycans, it occurs as a structural and antigenic component of important cell surface molecules in a variety of microbes, ranging from bacteria to parasites and fungi. One such organism is Cryptococcus neoformans, a pathogenic yeast that causes lethal meningoencephalitis in immunocompromised individuals, particularly AIDS patients. C. neoformans is unique among fungal pathogens in bearing a complex polysaccharide capsule, a critical virulence factor reported to include Galf. Notably, how Galf modification contributes to the structure and function of the cryptococcal capsule is not known. We have determined that Galf is β1,2-linked to an unusual tetrasubstituted galactopyranose of the glucuronoxylomannogalactan (GXMGal) capsule polysaccharide. This discovery fills a longstanding gap in our understanding of a major polymer of the cryptococcal capsule. We also engineered a C. neoformans strain that lacks UDP-galactopyranose mutase; this enzyme forms UDP-Galf, the nucleotide sugar donor required for Galf addition. Mutase activity was required for the incorporation of Galf into glucuronoxylomannogalactan but was dispensable for vegetative growth, cell integrity, and virulence in a mouse model.

  18. The Type a and Type b Polysaccharide Capsules Predominate in an International Collection of Invasive Kingella kingae Isolates

    PubMed Central

    Porsch, Eric A.; Starr, Kimberly F.; Yagupsky, Pablo

    2017-01-01

    ABSTRACT Kingella kingae is an encapsulated Gram-negative bacterium and an important etiology of osteoarticular infections in young children. A recent study examining a diverse collection of carrier and invasive K. kingae isolates from Israel revealed four distinct polysaccharide capsule types. In this study, to obtain a global view of K. kingae capsule type diversity, we examined an international collection of isolates using a multiplex PCR approach. The collection contained all four previously identified capsule types and no new capsule types. Over 95% of invasive isolates in the collection were type a or type b, similar to the findings in Israel. These results suggest that the type a and type b polysaccharide capsules may have enhanced pathogenic properties or may mark clonal groups of strains with specific virulence genes. In addition, they raise the possibility that a vaccine containing the type a and type b capsules might be an effective approach to preventing K. kingae disease. IMPORTANCE Kingella kingae has emerged as a significant cause of septic arthritis, osteomyelitis, and bacteremia in young children. A recent study examining a diverse collection of K. kingae isolates from Israel revealed four different polysaccharide capsule types in this species, designated types a to d. To determine the global distribution of K. kingae capsule types, we assembled and capsule typed an international collection of K. kingae isolates. The findings reported here show that the type a and type b capsules represent >95% of the invasive isolates, similar to the Israeli isolate collection, suggesting that a polysaccharide-based vaccine targeting these two capsules could be an attractive approach to prevent K. kingae disease. PMID:28317027

  19. The Type a and Type b Polysaccharide Capsules Predominate in an International Collection of Invasive Kingella kingae Isolates.

    PubMed

    Porsch, Eric A; Starr, Kimberly F; Yagupsky, Pablo; St Geme, Joseph W

    2017-01-01

    Kingella kingae is an encapsulated Gram-negative bacterium and an important etiology of osteoarticular infections in young children. A recent study examining a diverse collection of carrier and invasive K. kingae isolates from Israel revealed four distinct polysaccharide capsule types. In this study, to obtain a global view of K. kingae capsule type diversity, we examined an international collection of isolates using a multiplex PCR approach. The collection contained all four previously identified capsule types and no new capsule types. Over 95% of invasive isolates in the collection were type a or type b, similar to the findings in Israel. These results suggest that the type a and type b polysaccharide capsules may have enhanced pathogenic properties or may mark clonal groups of strains with specific virulence genes. In addition, they raise the possibility that a vaccine containing the type a and type b capsules might be an effective approach to preventing K. kingae disease. IMPORTANCEKingella kingae has emerged as a significant cause of septic arthritis, osteomyelitis, and bacteremia in young children. A recent study examining a diverse collection of K. kingae isolates from Israel revealed four different polysaccharide capsule types in this species, designated types a to d. To determine the global distribution of K. kingae capsule types, we assembled and capsule typed an international collection of K. kingae isolates. The findings reported here show that the type a and type b capsules represent >95% of the invasive isolates, similar to the Israeli isolate collection, suggesting that a polysaccharide-based vaccine targeting these two capsules could be an attractive approach to prevent K. kingae disease.

  20. Evidence for a Role of the Polysaccharide Capsule Transport Proteins in Pertussis Pathogenesis

    PubMed Central

    Hoo, Regina; Lam, Jian Hang; Huot, Ludovic; Pant, Aakanksha; Li, Rui; Hot, David; Alonso, Sylvie

    2014-01-01

    Polysaccharide (PS) capsules are important virulence determinants for many bacterial pathogens. Bordetella pertussis, the agent of whooping cough, produces a surface associated microcapsule but its role in pertussis pathogenesis remained unknown. Here we showed that the B. pertussis capsule locus is expressed in vivo in murine lungs and that absence of the membrane-associated protein KpsT, involved in the transport of the PS polymers across the envelope, but not the surface-exposed PS capsule itself, affects drastically B. pertussis colonization efficacy in mice. Microarray analysis revealed that absence of KpsT in B. pertussis resulted in global down-regulation of gene expression including key virulence genes regulated by BvgA/S, the master two-component system. Using a BvgS phase-locked mutant, we demonstrated a functional link between KpsT and BvgA/S-mediated signal transduction. Whereas pull-down assays do not support physical interaction between BvgS sensor and any of the capsule locus encoded proteins, absence of KpsT impaired BvgS oligomerization, necessary for BvgS function. Furthermore, complementation studies indicated that instead of KpsT alone, the entire PS capsule transport machinery spanning the cell envelope likely plays a role in BvgS-mediated signal transduction. Our work thus provides the first experimental evidence of a role for a virulence-repressed gene in pertussis pathogenesis. PMID:25501560

  1. Evidence for a role of the polysaccharide capsule transport proteins in pertussis pathogenesis.

    PubMed

    Hoo, Regina; Lam, Jian Hang; Huot, Ludovic; Pant, Aakanksha; Li, Rui; Hot, David; Alonso, Sylvie

    2014-01-01

    Polysaccharide (PS) capsules are important virulence determinants for many bacterial pathogens. Bordetella pertussis, the agent of whooping cough, produces a surface associated microcapsule but its role in pertussis pathogenesis remained unknown. Here we showed that the B. pertussis capsule locus is expressed in vivo in murine lungs and that absence of the membrane-associated protein KpsT, involved in the transport of the PS polymers across the envelope, but not the surface-exposed PS capsule itself, affects drastically B. pertussis colonization efficacy in mice. Microarray analysis revealed that absence of KpsT in B. pertussis resulted in global down-regulation of gene expression including key virulence genes regulated by BvgA/S, the master two-component system. Using a BvgS phase-locked mutant, we demonstrated a functional link between KpsT and BvgA/S-mediated signal transduction. Whereas pull-down assays do not support physical interaction between BvgS sensor and any of the capsule locus encoded proteins, absence of KpsT impaired BvgS oligomerization, necessary for BvgS function. Furthermore, complementation studies indicated that instead of KpsT alone, the entire PS capsule transport machinery spanning the cell envelope likely plays a role in BvgS-mediated signal transduction. Our work thus provides the first experimental evidence of a role for a virulence-repressed gene in pertussis pathogenesis.

  2. Effects of alga polysaccharide capsule shells on in-vivo bioavailability and disintegration

    NASA Astrophysics Data System (ADS)

    Li, Ting; Guo, Shuju; Ma, Lin; Yuan, Yi; Han, Lijun

    2012-01-01

    Gelatin has been used in hard capsule shells for more than a century, and some shortcomings have appeared, such as high moisture content and risk of transmitting diseases of animal origin to people. Based on available studies regarding gelatin and vegetable shells, we developed a new type of algal polysaccharide capsule (APPC) shells. To test whether our products can replace commercial gelatin shells, we measured in-vivo plasma concentration of 12 selected volunteers with a model drug, ibuprofen, using high performance liquid chromatography (HPLC), by calculating the relative bioavailability of APPC and Qualicaps® referenced to gelatin capsules and assessing bioequivalence of the three types of shells, and calculated pharmacokinetic parameters with the software DAS 2.0 (China). The results show that APPC shells possess bioequivalence with Qualicaps® and gelatin shells. Moreover, the disintegration behavior of four types of shells (APPC, Vegcaps®, Qualicaps® and gelatin shells) with the content of lactose and radioactive element (99mTc) was observed via gamma-scintigraphic images. The bioavailability and gamma-scintigraphic studies showed that APPC was not statistically different from other vegetable and gelatin capsule shells with respect to in-vivo behavior. Hence, it can be concluded that APPCs are exchangeable with other vegetable and gelatin shells.

  3. Cryptococcal xylosyltransferase 1 (Cxt1p) from Cryptococcus neoformans plays a direct role in the synthesis of capsule polysaccharides.

    PubMed

    Klutts, J Stacey; Doering, Tamara L

    2008-05-23

    The opportunistic yeast Cryptococcus neoformans causes serious disease in humans and expresses a prominent polysaccharide capsule that is required for its virulence. Little is known about how this capsule is synthesized. We previously identified a beta1,2-xylosyltransferase (Cxt1p) with in vitro enzymatic activity appropriate for involvement in capsule synthesis. Here, we investigate C. neoformans strains in which the corresponding gene has been deleted (cxt1Delta). Loss of CXT1 does not affect in vitro growth of the mutant cells or the general morphology of their capsules. However, NMR structural analysis of the two main capsule polysaccharides, glucuronoxylomannan (GXM) and galactoxylomannan (GalXM), showed that both were missing beta1,2-xylose residues. There was an approximately 30% reduction in the abundance of this residue in GXM in mutant compared with wild-type strains, and mutant GalXM was almost completely devoid of beta1,2-linked xylose. The GalXM from the mutant strain was also missing a beta1,3-linked xylose residue. Furthermore, deletion of CXT1 led to attenuation of cryptococcal growth in a mouse model of infection, suggesting that the affected xylose residues are important for normal host-pathogen interactions. Cxt1p is the first glycosyltransferase with a defined role in C. neoformans capsule biosynthesis, and cxt1Delta is the only strain identified to date with structural alterations of the capsule polysaccharide GalXM.

  4. Differential regulation of polysaccharide-specific antibody responses to isolated polysaccharides, conjugate vaccines, and intact Gram-positive versus Gram-negative extracellular bacteria.

    PubMed

    Snapper, Clifford M

    2016-06-24

    Bacterial capsular polysaccharides are major virulence factors and are key targets in a number of licensed anti-bacterial vaccines. Their major characteristics are their large molecular weight and expression of repeating antigenic epitopes that mediate multivalent B cell receptor cross-linking. In addition, since the majority of these antigens cannot associate with MHC-II they fail to recruit CD4+ T cell help and are referred to as T cell-independent antigens. In this review I will discuss a series of studies from my laboratory that have underscored the importance of understanding polysaccharide-specific antibody responses within the context in which the PS is expressed (i.e. in isolation, as a component of conjugate vaccines, and expressed naturally by intact bacteria). We have shown that multivalent B cell receptor crosslinking, as mediated by polysaccharides, uniquely determines the qualitative response of the B cell to subsequent stimuli, but by itself is insufficient to induce antibody secretion or class switching. For these latter events to occur, second signals must act in concert with primary signals derived from the B cell receptor. The co-expression of polysaccharide and protein within intact bacteria promotes recruitment of CD4+ T cell help for the associated PS-specific IgG response, in contrast to isolated polysaccharides. Further, the particulate nature of extracellular bacteria confers properties to the polysaccharide-specific IgG response that makes it distinct immunologically from soluble conjugate vaccines. Finally, the underlying biochemical and/or structural differences that distinguish Gram-positive and Gram-negative bacteria appear to play critical roles in differentially regulating the associated polysaccharide-specific IgG responses to these groups of pathogens. These studies have a number of implications for the understanding and future design of polysaccharide-based vaccines. Published by Elsevier Ltd.

  5. Fluconazole alters the polysaccharide capsule of Cryptococcus gattii and leads to distinct behaviors in murine Cryptococcosis.

    PubMed

    Santos, Julliana Ribeiro Alves; Holanda, Rodrigo Assunção; Frases, Susana; Bravim, Mayara; Araujo, Glauber de S; Santos, Patrícia Campi; Costa, Marliete Carvalho; Ribeiro, Maira Juliana Andrade; Ferreira, Gabriella Freitas; Baltazar, Ludmila Matos; Miranda, Aline Silva; Oliveira, Danilo Bretas; Santos, Carolina Maria Araújo; Fontes, Alide Caroline Lima; Gouveia, Ludmila Ferreira; Resende-Stoianoff, Maria Aparecida; Abrahão, Jonatas Santos; Teixeira, Antônio Lúcio; Paixão, Tatiane Alves; Souza, Danielle G; Santos, Daniel Assis

    2014-01-01

    Cryptococcus gattii is an emergent human pathogen. Fluconazole is commonly used for treatment of cryptococcosis, but the emergence of less susceptible strains to this azole is a global problem and also the data regarding fluconazole-resistant cryptococcosis are scarce. We evaluate the influence of fluconazole on murine cryptococcosis and whether this azole alters the polysaccharide (PS) from cryptococcal cells. L27/01 strain of C. gattii was cultivated in high fluconazole concentrations and developed decreased drug susceptibility. This phenotype was named L27/01F, that was less virulent than L27/01 in mice. The physical, structural and electrophoretic properties of the PS capsule of L27/01F were altered by fluconazole. L27/01F presented lower antiphagocytic properties and reduced survival inside macrophages. The L27/01F did not affect the central nervous system, while the effect in brain caused by L27/01 strain began after only 12 hours. Mice infected with L27/01F presented lower production of the pro-inflammatory cytokines, with increased cellular recruitment in the lungs and severe pulmonary disease. The behavioral alterations were affected by L27/01, but no effects were detected after infection with L27/01F. Our results suggest that stress to fluconazole alters the capsule of C. gattii and influences the clinical manifestations of cryptococcosis.

  6. Fluconazole Alters the Polysaccharide Capsule of Cryptococcus gattii and Leads to Distinct Behaviors in Murine Cryptococcosis

    PubMed Central

    Santos, Julliana Ribeiro Alves; Holanda, Rodrigo Assunção; Frases, Susana; Bravim, Mayara; Araujo, Glauber de S.; Santos, Patrícia Campi; Costa, Marliete Carvalho; Ribeiro, Maira Juliana Andrade; Ferreira, Gabriella Freitas; Baltazar, Ludmila Matos; Miranda, Aline Silva; Oliveira, Danilo Bretas; Santos, Carolina Maria Araújo; Fontes, Alide Caroline Lima; Gouveia, Ludmila Ferreira; Resende-Stoianoff, Maria Aparecida; Abrahão, Jonatas Santos; Teixeira, Antônio Lúcio; Paixão, Tatiane Alves; Souza, Danielle G.; Santos, Daniel Assis

    2014-01-01

    Cryptococcus gattii is an emergent human pathogen. Fluconazole is commonly used for treatment of cryptococcosis, but the emergence of less susceptible strains to this azole is a global problem and also the data regarding fluconazole-resistant cryptococcosis are scarce. We evaluate the influence of fluconazole on murine cryptococcosis and whether this azole alters the polysaccharide (PS) from cryptococcal cells. L27/01 strain of C. gattii was cultivated in high fluconazole concentrations and developed decreased drug susceptibility. This phenotype was named L27/01F, that was less virulent than L27/01 in mice. The physical, structural and electrophoretic properties of the PS capsule of L27/01F were altered by fluconazole. L27/01F presented lower antiphagocytic properties and reduced survival inside macrophages. The L27/01F did not affect the central nervous system, while the effect in brain caused by L27/01 strain began after only 12 hours. Mice infected with L27/01F presented lower production of the pro-inflammatory cytokines, with increased cellular recruitment in the lungs and severe pulmonary disease. The behavioral alterations were affected by L27/01, but no effects were detected after infection with L27/01F. Our results suggest that stress to fluconazole alters the capsule of C. gattii and influences the clinical manifestations of cryptococcosis. PMID:25392951

  7. A Patency Capsule Remained Intact in the Colon over 210 Hours

    PubMed Central

    Hihara, Yu; Takahashi, Toshiharu; Okaniwa, Shinji; Mizukami, Yoshiki; Nakamura, Yoshiyuki

    2017-01-01

    We present an unusual case of a 35-year-old male patient whom a patency capsule stayed in his gut without breaking. He has a history of Peutz-Jeghers syndrome and multiple abdominal surgeries. Prestudy was performed for abdominal searching, but a patency capsule remained in the colon over 9 days. He displayed neither abdominal nor obstructive symptoms in that period. We collected the patency capsule using colonoscopy after dilating a postoperative stricture at an anastomotic site of the rectum. Clinicians should bear in mind that patency capsules may become retained as distally as the colon in patients with a surgical history of the large intestine. PMID:28321345

  8. Finite-element model of interaction between fungal polysaccharide and monoclonal antibody in the capsule of Cryptococcus neoformans

    PubMed Central

    Rakesh, Vineet; Schweitzer, Andrew D.; Zaragoza, Oscar; Bryan, Ruth; Wong, Kevin; Datta, Ashim; Casadevall, Arturo; Dadachova, Ekaterina

    2008-01-01

    Many microorganisms such as bacteria and fungi possess so-called capsules made of polysaccharides which protect these microorganisms from environmental insults and host immune defenses. The polysaccharide capsule of C. neoformans, a human pathogenic yeast, is capable of self assembly, composed mostly of glucuronoxylomannan (GXM), a polysaccharide with molecular weight of approximately 2,000,000 Da and has several layers with different densities. The objective of this study was to model pore-hindered diffusion and binding of the GXM-specific antibody within the C. neoformans capsule. Using the finite element method (FEM), we created a model which represents the in vivo binding of GXM-specific antibody to a C. neoformans cell taking into account the intravenous infusion time of antibody, antibody diffusion through capsular pores, and Michaelis-Menten kinetics of antibody binding to capsular GXM. The model predicted rapid diffusion of antibody to all regions of the capsule where pore size was greater than the Stokes diameter of the antibody. Binding occurred primarily at intermediate regions of the capsule. The GXM concentration in each capsular region was the principal determinant of the steady-state antibody-GXM complex concentration, while the forward binding rate constant influenced the rate of complex formation in each region. The concentration profiles predicted by the model closely matched experimental immunofluorescence data. Inclusion of different antibody isotypes (IgG, IgA and IgM) into the modeling algorithm resulted in similar complex formation in outer capsular regions, but different depth of binding at inner regions. These results have implications for the development of new antibody-based therapies. PMID:18588334

  9. Capsule polysaccharide conjugate vaccine against diarrheal disease caused by Campylobacter jejuni.

    PubMed

    Monteiro, Mario A; Baqar, Shahida; Hall, Eric R; Chen, Yu-Han; Porter, Chad K; Bentzel, David E; Applebee, Lisa; Guerry, Patricia

    2009-03-01

    The capsule polysaccharide (CPS) of Campylobacter jejuni is one of the few identified virulence determinants of this important human pathogen. Since CPS conjugate vaccines have been so effective against other mucosal pathogens, we evaluated this approach using CPSs from two strains of C. jejuni, 81-176 (HS23 and HS36 serotype complex) and CG8486 (HS4 serotype complex). The CPSs of 81-176 and CG8486 were independently linked to the carrier protein CRM(197) by reductive amination between an aldehyde(s), strategically created at the nonreducing end of each CPS, and accessible amines of CRM(197). In both cases, the CPS:CRM(197) ratio used was 2:1 by weight. Mass spectrometry and gel electrophoresis showed that on average, each glycoconjugate preparation contained, at least in part, two to five CPSs attached to one CRM(197). When administered subcutaneously to mice, these vaccines elicited robust immune responses and significantly reduced the disease following intranasal challenge with the homologous strains of C. jejuni. The CPS(81-176)-CRM(197) vaccine also provided 100% protection against diarrhea in the New World monkey Aotus nancymaae following orogastric challenge with C. jejuni 81-176.

  10. Comparison of the pharmacokinetics of lansoprazole 15- and 30-mg sachets for suspension versus intact capsules.

    PubMed

    Amer, Fouad; Karol, Michael D; Pan, Wei-Jian; Griffin, Janice S; Lukasik, Nancy L; Locke, Charles S; Chiu, Yi-Lin

    2004-12-01

    The pharmacokinetic profiles of single doses of lansoprazole 15- and 30-mg sachets for suspension were compared with those of corresponding doses of lansoprazole oral capsules. Healthy adult male and female subjects were randomized (1:1 ratio) into 2 Phase 1, open-label, single-dose, 2-sequence, 2-period complete crossover studies. In the first study, each subject received 1 lansoprazole 15-mg sachet mixed with water and 1 lansoprazole 15-mg oral capsule; in the second study, each subject received 1 lansoprazole 30-mg sachet mixed with water and 1 lansoprazole 30-mg oral capsule. Administration of the 2 formulations was separated by a washout period of > or =7 days. Blood samples were collected before and after each administration to assess the pharmacokinetic parameters of lansoprazole and bioequivalence between suspension and capsule. Thirty-six subjects (19 males, 17 females) with a mean (SD) age of 32.0 (9.6) years and mean (SD) body weight of 68.6 (10.5) kg received lansoprazole 15 mg. Thirty-six subjects (22 males, 14 females) with a mean (SD) age of 38.0 (8.3) years and mean (SD) body weight of 75.1 (9.7) kg received lansoprazole 30 mg. The pharmacokinetic parameters of the 15- and 30-mg lansoprazole sachets for suspension were similar to those of the corresponding doses of the oral capsules. The mean (SD) values for C(max) and AUC from time 0 to infinity (AUC(0-infinity) for the lansoprazole 15-mg sachet (591.9 [242.3] ng/mL and 1614 [2065] ng.h/mL, respectively) did not differ significantly from those for the lansoprazole 15-mg capsules (578.6 [275.2] ng/mL and 1620 [2290] ng.h/mL, respectively). These parameters also did not differ significantly between the lansoprazole 30-mg sachet and 30-mg capsule: mean (SD) C(max), 1103 (428.3) and 1077 (465.6) ng/mL, respectively; mean (SD) AUC(0-infinity), 2655 (1338) and 2669 (1311) ng.h/mL, respectively. The 90% Cls for C(max) and AUC(0-infinity) ratios were contained within the 0.80 to 1.25 equivalence range

  11. Binding of purified and radioiodinated capsular polysaccharides from Cryptococcus neoformans serotype A strains to capsule-free mutants

    SciTech Connect

    Small, J.M.; Mitchell, T.G.

    1986-12-01

    Strains 6, 15, 98, 110, and 145 of Cryptococcus neoformans serotype A vary in capsule size, animal virulence, and susceptibility to in vitro phagocytosis. The isolated capsular polysaccharides (CPSs) differ in monosaccharide composition ratios and molecular size, as determined by gel filtration. The purpose of this investigation was to characterize the binding of CPSs to capsule-free mutants of C. neoformans and to examine CPSs from these strains for differences in their ability to bind, to determine whether such differences might explain the variation in the pathobiology of these strains. CPSs were partially periodate oxidized, tyraminated, iodinated with /sup 125/I, and used in binding studies with two capsule-free mutants of C. neoformans, strain 602 and Cap59. Binding was specific for yeast species and for polysaccharide and was saturable, which is consistent with a receptor-mediated mechanism of attachment. Binding occurred rapidly and was only slowly reversible. Binding was also independent of pH from pH 5.5 to 8, of cation concentrations, and of competition by sugars up to 1.0 M concentrations. Only a portion of CPS was capable of binding, and strains varied in the extent to which their CPS bound. CPS-15-IV (peak IV was the major polysaccharide peak on DEAE-cellulose chromatography of CPS from strain 15) had the highest proportion of binding (40%), followed by CPS from strains 98, 6, 145, 110, and 15-III (peak III was an earlier eluting fraction of CPS from strain 15). The CPSs differed similarly in their ability to competitively inhibit binding. Treatment of CPS, but not yeast cells, with proteinase XIV abolished binding without altering the CPS gross structure. Treatment of yeast cells with proteases, heat, or formaldehyde did not alter binding, and both strain 602 and Cap59 bound CPS similarly. Binding to encapsulated yeast cells was minimal.

  12. The polysaccharide capsule of Streptococcus pneumonia partially impedes MyD88-mediated immunity during pneumonia in mice.

    PubMed

    de Vos, Alex F; Dessing, Mark C; Lammers, Adriana J J; de Porto, Alexander P N A; Florquin, Sandrine; de Boer, Onno J; de Beer, Regina; Terpstra, Sanne; Bootsma, Hester J; Hermans, Peter W; van 't Veer, Cornelis; van der Poll, Tom

    2015-01-01

    Toll-like receptors (TLR) and the downstream adaptor protein MyD88 are considered crucial for protective immunity during bacterial infections. Streptococcus (S.) pneumoniae is a human respiratory pathogen and a large majority of clinical pneumococcal isolates expresses an external polysaccharide capsule. We here sought to determine the role of pneumococcal capsule in MyD88-mediated antibacterial defense during S. pneumonia pneumonia. Wild type (WT) and Myd88(-/-) mice were inoculated intranasally with serotype 2 S. pneumoniae D39 or with an isogenic capsule locus deletion mutant (D39∆cps), and analysed for bacterial outgrowth and inflammatory responses in the lung. As compared to WT mice, Myd88(-/-) mice infected with D39 demonstrated a modestly impaired bacterial clearance accompanied by decreased inflammatory responses in the lung. Strikingly, while WT mice rapidly cleared D39∆cps, Myd88(-/-) mice showed 105-fold higher bacterial burdens in their lungs and dissemination to blood 24 hours after infection. These data suggest that the pneumococcal capsule impairs recognition of TLR ligands expressed by S. pneumoniae and thereby partially impedes MyD88-mediated antibacterial defense.

  13. Klebsiella pneumoniae Capsule Polysaccharide Impedes the Expression of β-Defensins by Airway Epithelial Cells▿

    PubMed Central

    Moranta, David; Regueiro, Verónica; March, Catalina; Llobet, Enrique; Margareto, Javier; Larrate, Eider; Garmendia, Junkal; Bengoechea, José A.

    2010-01-01

    Human β-defensins (hBDs) contribute to the protection of the respiratory tract against pathogens. It is reasonable to postulate that pathogens have developed countermeasures to resist them. Klebsiella pneumoniae capsule polysaccharide (CPS), but not the lipopolysaccharide O antigen, mediated resistance against hBD1 and hBD2. hBD3 was the most potent hBD against Klebsiella. We investigated the possibility that as a strategy for survival in the lung, K. pneumoniae may not activate the expression of hBDs. Infection of A549 and normal human bronchial cells with 52145-ΔwcaK2, a CPS mutant, increased the expression of hBD2 and hBD3. Neither the wild type nor the lipopolysaccharide O antigen mutant increased the expression of hBDs. In vivo, 52145-ΔwcaK2 induced higher levels of mBD4 and mBD14, possible mouse orthologues of hBD2 and hBD3, respectively, than the wild type. 52145-ΔwcaK2-dependent upregulation of hBD2 occurred via NF-κB and mitogen-activated protein kinases (MAPKs) p44/42, Jun N-terminal protein kinase (JNK)-dependent pathways. The increase in hBD3 expression was dependent on the MAPK JNK. 52145-ΔwcaK2 engaged Toll-like receptors 2 and 4 (TLR2 and TLR4) to activate hBD2, whereas hBD3 expression was dependent on NOD1. K. pneumoniae induced the expression of CYLD and MKP-1, which act as negative regulators for 52145-ΔwcaK2-induced expression of hBDs. Bacterial engagement of pattern recognition receptors induced CYLD and MKP-1, which may initiate the attenuation of proinflammatory pathways. The results of this study indicate that K. pneumoniae CPS not only protects the pathogen from the bactericidal action of defensins but also impedes their expression. These features of K. pneumoniae CPS may facilitate pathogen survival in the hostile environment of the lung. PMID:20008534

  14. Opened Proton Pump Inhibitor Capsules Reduce Time to Healing Compared With Intact Capsules for Marginal Ulceration Following Roux-en-Y Gastric Bypass.

    PubMed

    Schulman, Allison R; Chan, Walter W; Devery, Aiofe; Ryan, Michele B; Thompson, Christopher C

    2017-04-01

    Marginal ulceration, or ulceration at the gastrojejunal anastomosis, is a common complication of Roux-en-Y gastric bypass (RYGB). Acidity likely contributes to the pathophysiology, and proton pump inhibitors (PPIs) frequently are prescribed for treatment. However, patients with gastric bypass only have a small gastric pouch and rapid small-bowel transit, which limits the opportunity for capsule breakdown and PPI absorption. Soluble PPIs (open capsules [OCs]) might be absorbed more easily than intact capsules (ICs). We compared time to ulcer healing, number of endoscopic procedures, and use of health care for patients with marginal ulceration who received PPIs in OC vs IC form. We performed a retrospective study of 164 patients diagnosed with marginal ulceration who underwent RYGB at the Brigham and Women's Hospital from 2000 through 2015. Patients received high-dose PPIs and underwent repeat endoscopy every 3 months until ulcer healing was confirmed. We used time-to-event analysis with a Cox proportional hazards model to evaluate the association between mode of PPI administration and time to ulcer healing, in addition to Cox multivariate regression analysis. Total charge (procedural and maintenance) was determined by comparison of categorized charges incurred from time of ulcer diagnosis to resolution. The primary outcome was time to healing of marginal ulceration in RYGB patients receiving high-dose PPIs in OC vs IC form. A total of 162 patients were included (115 received OC and 49 received IC). All patients were followed up until ulcer healing was confirmed. The median time to ulcer healing was 91.0 days for the OC group vs 342.0 days for the IC group (P < .001). OC was the only independent predictor of time to ulcer healing (P < .001) when we controlled for known risk factors. The number of endoscopic procedures (P = .02) and overall health care utilization (P = .05) were lower in the OC than the IC group. Patients with marginal ulceration after RYGB who

  15. The Regulation of Polysaccharide Specific Humoral Immune Response Against Intact Streptococcus Pneumoniae

    DTIC Science & Technology

    2008-06-19

    antigens are generally present on the Gram -positive or Gram -negative bacterial cell surface in the form of a capsule, or as outer membrane, cell wall or...cytoplasmic glycoproteins or glycolipids including lipopolysaccharides (LPS), teichoic acids, lipoteichoic acids, and peptidoglycan (Jennings...Epidemiology & pathogenesis- Pn is a Gram -positive extracellular coccus grown on blood agar medium and is alpha-hemolytic (Fig.1). Individual cells are

  16. Structure of the neutral capsular polysaccharide of Acinetobacter baumannii NIPH146 that carries the KL37 capsule gene cluster.

    PubMed

    Arbatsky, Nikolay P; Shneider, Mikhail M; Kenyon, Johanna J; Shashkov, Alexander S; Popova, Anastasiya V; Miroshnikov, Konstantin A; Volozhantsev, Nikolay V; Knirel, Yuriy A

    2015-09-02

    Capsular polysaccharide (CPS) was isolated from Acinetobacter baumannii NIPH146, and the following structure of branched pentasaccharide repeating unit was established by sugar analyses along with 1D and 2D NMR spectroscopy: In comparison to most other known capsular polysaccharides of A. baumannii, the CPS studied is neutral and lacks any specific monosaccharide component. The synthesis, assembly and export of this structure could be attributed to genes in a novel capsule biosynthesis gene cluster, designated KL37, which was found in the NIPH146 genome. The CPS of A. baumannii NIPH146 shares the α-d-Galp-(1→6)-β-d-Glcp-(1→3)-d-GalpNAc-(1→ trisaccharide fragment with the CPS units of several A. baumannii strains, including ATCC 17978 and LUH 5537 that carry the KL3 and KL22 gene clusters, respectively. KL37 contains two genes for glycosyltransferases that are related to two glycosyltransferase genes present in both KL3 and KL22, and the encoded proteins could be tentatively assigned to linkages between sugars in the CPS repeat.

  17. The Polysaccharide Capsule of Campylobacter jejuni 81-176 Modulates the Host Immune Response

    DTIC Science & Technology

    2012-12-17

    The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing ...instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send...jejuni is a major cause of bacterial diarrheal disease worldwide. The organism is characterized by a diversity of polysaccharide structures

  18. Clinical utility of topiramate extended-release capsules (USL255): Bioequivalence of USL255 sprinkled and intact capsule in healthy adults and an in vitro evaluation of sprinkle delivery via enteral feeding tubes.

    PubMed

    Clark, Annie M; Pellock, John M; Holmay, Mary; Anders, Bob; Cloyd, James

    2016-04-01

    The objectives of these two studies were to determine if beads from extended-release topiramate capsules sprinkled onto soft food are bioequivalent to the intact capsule and if beads from the capsule can be passed through enteral gastrostomy (G-) and jejunostomy (J-) feeding tubes. Bioequivalence of 200-mg USL255 (Qudexy XR [topiramate] extended-release capsules) sprinkled onto soft food (applesauce) versus the intact capsule was evaluated in a phase 1, randomized, single-dose, crossover study (N=36). Pharmacokinetic evaluations included area under the curve (AUC), maximum plasma concentration (Cmax), time to Cmax (Tmax), and terminal elimination half-life (t1/2). If 90% confidence intervals (CI) of the ratio of geometric least-squares means were between 0.80 and 1.25, AUC and Cmax were considered bioequivalent. In separate in vitro experiments, 100-mg USL255 beads were passed through feeding tubes using gentle syringe pressure to develop a clog-free bead-delivery method. Multiple tube sizes (14- to 18-French [Fr] tubes), dilutions (5 mg/15 mL-25 mg/15 mL), and diluents (deionized water, apple juice, Ketocal, sparkling water) were tested. Area under the curve and Cmax for USL255 beads sprinkled onto applesauce were bioequivalent to the intact capsule (GLSM [90% CI]: AUC0-t 1.01 [0.97-1.04], AUC0-∞ 1.02 [0.98-1.05]; Cmax 1.09 [1.03-1.14]). Median Tmax was 4h earlier for USL255 sprinkled versus the intact capsule (10 vs 14 h; p=0.0018), and t1/2 was similar (84 vs 82 h, respectively). In 14-Fr G-tubes, USL255 beads diluted in Ketocal minimized bead clogging versus deionized water. Recovery of USL255 beads diluted in deionized water was nearly 100% in 16-Fr G-, 18-Fr G-, and 18-Fr J-tubes. For patients with difficulty swallowing pills, USL255 sprinkled onto applesauce offers a useful once-daily option for taking topiramate. USL255 beads were also successfully delivered in vitro through ≥14-Fr G- or J-tubes, with tube clogging minimized by portioning the dose and

  19. Spatial and Temporal Deposition of Adhesive Extracellular Polysaccharide Capsule and Fimbriae by Hyphomonas Strain MHS-3

    PubMed Central

    Quintero, Ernesto J.; Busch, Kathryn; Weiner, Ronald M.

    1998-01-01

    Hyphomonas strain MHS-3, a member of a genus of primary colonizers of surfaces immersed in marine water, synthesizes two structures that mediate adhesion to solid substrata, namely, capsular exopolysaccharide and fimbriae. Specific stains, gold-labelled lectins, and monoclonal antibodies, along with transmission electron microscopy of synchronized populations, revealed that both structures are polarly and temporally expressed. The timed synthesis and placement of the fimbriae and capsule correlated with the timing and locus of MHS-3 adhesion. PMID:16349537

  20. Differential idiotype utilization for the in vivo type 14 capsular polysaccharide-specific immunoglobulin responses to intact Streptococcus pneumoniae versus a pneumococcal conjugate vaccine

    PubMed Central

    Colino, Jesus; Duke, Leah; Arjunaraja, Swadhinya; Chen, Quanyi; Liu, Leyu; Lucas, Alexander H.; Snapper, Clifford M.

    2012-01-01

    Murine IgG responses specific for the capsular polysaccharide (PPS14) of Streptococcus pneumoniae type 14 (Pn14) induced in response to intact Pn14 or a PPS14-protein conjugate are both dependent on CD4+ T cell help, but appear to utilize marginal zone versus follicular B cells, respectively. Here we identify an idiotype (44.1-Id) that dominates the PPS14-specific IgG, but not IgM, responses to intact Pn14, isolated PPS14 and Group B Streptococcus (strain COH1-11) expressing capsular polysaccharide structurally identical to PPS14. The 44.1-Id is however not expressed in the repertoire of natural PPS14-specific antibodies. In distinct contrast, PPS14-specific IgG responses to a soluble PPS14-protein conjugate exhibits minimal usage of the 44.1-Id, although significant 44.1-Id expression is elicited in response to conjugate attached to particles. The 44.1-Id elicited in response to intact Pn14 was expressed in similar proportions among all 4 IgG subclasses during both the primary and secondary responses. 44.1-Id usage was linked to the Igha, but not Ighb, allotype and was associated with induction of relatively high total PPS14-specific IgG responses. In contrast to PPS14-protein conjugate, avidity maturation of the 44.1-Id-dominant PPS14-specific IgG responses were limited, even during the highly boosted T cell-dependent PPS14-specific secondary responses to COH1-11. These results indicate that different antigenic forms of the same capsular polysaccharide can recruit distinct B cell clones expressing characteristic idiotypes under genetic control, and suggest that the 44.1-Id is derived from marginal zone B cells. PMID:22706079

  1. Relative bioavailability of single doses of prolonged-release tacrolimus administered as a suspension, orally or via a nasogastric tube, compared with intact capsules: a phase 1 study in healthy participants.

    PubMed

    Undre, Nasrullah; Dickinson, James

    2017-04-04

    Tacrolimus, an immunosuppressant widely used in solid organ transplantation, is available as a prolonged-release capsule for once-daily oral administration. In the immediate postsurgical period, if patients cannot take intact capsules orally, tacrolimus therapy is often initiated as a suspension of the capsule contents, delivered orally or via a nasogastric tube. This study evaluated the relative bioavailability of prolonged-release tacrolimus suspension versus intact capsules in healthy participants. A phase 1, open-label, single-dose, cross-over study. A single clinical research unit. In total, 20 male participants, 18-55 years old, entered and completed the study. All participants received nasogastric administration of tacrolimus 10 mg suspension in treatment period 1, with randomisation to oral administration of suspension or intact capsules in periods 2 and 3. Blood concentration-time profile over 144 hours was used to estimate pharmacokinetic parameters. Primary end point: relative bioavailability of prolonged-release intact capsule versus oral or nasogastric administration of prolonged-release tacrolimus suspension (area under the concentration-time curve (AUC) from time 0 to infinity post-tacrolimus dose (AUC0-∞); AUC measured until the last quantifiable concentration (AUC0-tz); maximum observed concentration (Cmax); time to Cmax (Tmax)). Tolerability was assessed throughout the study. Relative bioavailability of prolonged-release tacrolimus suspension administered orally was similar to intact capsules, with a ratio of least-square means for AUC0-tz and AUC0-∞ of 1.05 (90% CI 0.96 to 1.14). Bioavailability was lower with suspension administered via a nasogastric tube versus intact capsules (17%; ratio 0.83; CI 0.76 to 0.92). Cmax was higher for oral and nasogastric suspension (30% and 28%, respectively), and median Tmax was shorter (difference 1.0 and 1.5 hours postdose, respectively) versus intact capsules (2.0 hours). Single 10 mg doses of

  2. Relative bioavailability of single doses of prolonged-release tacrolimus administered as a suspension, orally or via a nasogastric tube, compared with intact capsules: a phase 1 study in healthy participants

    PubMed Central

    Undre, Nasrullah; Dickinson, James

    2017-01-01

    Objective Tacrolimus, an immunosuppressant widely used in solid organ transplantation, is available as a prolonged-release capsule for once-daily oral administration. In the immediate postsurgical period, if patients cannot take intact capsules orally, tacrolimus therapy is often initiated as a suspension of the capsule contents, delivered orally or via a nasogastric tube. This study evaluated the relative bioavailability of prolonged-release tacrolimus suspension versus intact capsules in healthy participants. Design A phase 1, open-label, single-dose, cross-over study. Setting A single clinical research unit. Participants In total, 20 male participants, 18–55 years old, entered and completed the study. Interventions All participants received nasogastric administration of tacrolimus 10 mg suspension in treatment period 1, with randomisation to oral administration of suspension or intact capsules in periods 2 and 3. Blood concentration–time profile over 144 hours was used to estimate pharmacokinetic parameters. Primary and secondary outcome measures Primary end point: relative bioavailability of prolonged-release intact capsule versus oral or nasogastric administration of prolonged-release tacrolimus suspension (area under the concentration–time curve (AUC) from time 0 to infinity post-tacrolimus dose (AUC0–∞); AUC measured until the last quantifiable concentration (AUC0–tz); maximum observed concentration (Cmax); time to Cmax (Tmax)). Tolerability was assessed throughout the study. Results Relative bioavailability of prolonged-release tacrolimus suspension administered orally was similar to intact capsules, with a ratio of least-square means for AUC0–tz and AUC0–∞ of 1.05 (90% CI 0.96 to 1.14). Bioavailability was lower with suspension administered via a nasogastric tube versus intact capsules (17%; ratio 0.83; CI 0.76 to 0.92). Cmax was higher for oral and nasogastric suspension (30% and 28%, respectively), and median Tmax was shorter

  3. Phenotypic Heterogeneity in Expression of the K1 Polysaccharide Capsule of Uropathogenic Escherichia coli and Downregulation of the Capsule Genes during Growth in Urine

    PubMed Central

    King, Jane E.; Aal Owaif, Hasan A.; Jia, Jia

    2015-01-01

    Uropathogenic Escherichia coli (UPEC) is the major causative agent of uncomplicated urinary tract infections (UTI). The K1 capsule on the surface of UPEC strains is a key virulence factor, and its expression may be important in the onset and progression of UTI. In order to understand capsule expression in more detail, we analyzed its expression in the UPEC strain UTI89 during growth in rich medium (LB medium) and urine and during infection of a bladder epithelial cell line. Comparison of capsule gene transcription using a chromosomal gfp reporter fusion showed a significant reduction in transcription during growth in urine compared to that during growth in LB medium. When examined at the single-cell level, following growth in both media, capsule gene expression appears to be heterogeneous, with two distinct green fluorescent protein (GFP)-expressing populations. Using anti-K1 antibody, we showed that this heterogeneity in gene expression results in two populations of encapsulated and unencapsulated cells. We demonstrated that the capsule hinders attachment to and invasion of epithelial cells and that the unencapsulated cells within the population preferentially adhere to and invade bladder epithelial cells. We found that once internalized, UTI89 starts to produce capsule to aid in its intracellular survival and spread. We propose that this observed phenotypic diversity in capsule expression is a fitness strategy used by the bacterium to deal with the constantly changing environment of the urinary tract. PMID:25870229

  4. Cloning of type 8 capsule genes and analysis of gene clusters for the production of different capsular polysaccharides in Staphylococcus aureus.

    PubMed

    Sau, S; Lee, C Y

    1996-04-01

    Eleven serotypes of capsular polysaccharide from Staphylococcus aureus have been reported. We have previously cloned a cluster of type 1 capsule (cap1) genes responsible for type 1 capsular polysaccharide biosynthesis in S. aureus M. To clone the type 8 capsule (cap8) genes, a plasmid library of type 8 strain Becker was screened with a labelled DNA fragment containing the cap1 genes under low-stringency conditions. One recombinant plasmid containing a 14-kb insert was chosen for further study and found to complement 14 of the 18 type 8 capsule-negative (Cap8-) mutants used in the study. Additional library screening, subcloning, and complementation experiments showed that all of the 18 Cap8- mutants were complemented by DNA fragments derived from a 20.5-kb contiguous region of the Becker chromosome. The mutants were mapped into six complementation groups, indicating that the cap8 genes are clustered. By Southern hybridization analyses under high-stringency conditions, we found that DNA fragments containing the cap8 gene cluster show extensive homology with all 17 strains tested, including type 1 strains. By further Southern analyses and cloning of the cap8-related homolog from strain M, we show that strain M carries an additional capsule gene cluster different from the cap1 gene cluster. In addition, by using DNA fragments containing different regions of the cap8 gene cluster as probes to hybridize DNA from different strains, we found that the central region of the cap8 gene cluster hybridizes only to DNAs from certain strains tested whereas the flanking regions hybridize to DNAs of all strains tested. Thus, the cap8 gene clusters and its closely related homologs are likely to have organizations similar to those of the encapsulation genes of other bacterial systems.

  5. Two variants among Haemophilus influenzae serotype b strains with distinct bcs4, hcsA and hcsB genes display differences in expression of the polysaccharide capsule

    PubMed Central

    Schouls, Leo; van der Heide, Han; Witteveen, Sandra; Zomer, Bert; van der Ende, Arie; Burger, Marina; Schot, Corrie

    2008-01-01

    Background Despite nearly complete vaccine coverage, a small number of fully vaccinated children in the Netherlands have experienced invasive disease caused by Haemophilus influenzae serotype b (Hib). This increase started in 2002, nine years after the introduction of nationwide vaccination in the Netherlands. The capsular polysaccharide of Hib is used as a conjugate vaccine to protect against Hib disease. To evaluate the possible rise of escape variants, explaining the increased number of vaccine failures we analyzed the composition of the capsular genes and the expressed polysaccharide of Dutch Hib strains collected before and after the introduction of Hib vaccination. Results The DNA sequences of the complete capsular gene clusters of 9 Dutch Hib strains were assessed and two variants, designated type I and type II were found. The two variants displayed considerable sequence divergence in the hcsA and hcsB genes, involved in transport of capsular polysaccharide to the cell surface. Application of hcsA type specific PCRs on 670 Hib strains collected from Dutch patients with invasive Hib disease showed that 5% of the strains collected before 1996 were type II. No endogenous type II Hib strains were isolated after 1995 and all type II strains were isolated from 0–4 year old, non-vaccinated children only. Analysis of a worldwide collection of Hib strains from the pre-vaccination era revealed considerable geographic differences in the distribution of the type I and type II strains with up to 73% of type II strains in the USA. NMR analysis of type I and type II capsule polysaccharides did not reveal structural differences. However, type I strains were shown to produce twice as much surface bound capsular polysaccharide. Conclusion Type II strains were only isolated during the pre-vaccination era from young, non-vaccinated individuals and displayed a lower expression of capsular polysaccharide than type I strains. The higher polysaccharide expression may have

  6. Pressure measurement in the cervical spinal facet joint: considerations for maintaining joint anatomy and an intact capsule.

    PubMed

    Jaumard, Nicolas V; Bauman, Joel A; Welch, William C; Winkelstein, Beth A

    2011-07-01

    A novel noninvasive approach to measure facet joint pressure in the cervical spine was investigated using a tip-mounted transducer that can be inserted through a hole in the bony lateral mass. This technique is advantageous because it does not require resection of the joint capsule, but there are potential issues regarding its applicability that are addressed. The objective was to evaluate the effect of a tip-mounted pressure probe's position and orientation on contact pressure measurements in biomechanical experiments. Measurements of direct contact pressure in the facet joint of cadaveric spines have been obtained via pressure-sensitive films. However, that method requires the resection of the facet capsule, which can alter the overall joint's mechanical behavior and can affect the measured contact pressures. Influence of position and orientation on probe measurements was evaluated in companion surrogate and cadaveric investigations. The probe was placed in the facet of an anatomic vertebral C4/5 surrogate undergoing sagittal bending moments. Pressure-sensitive paper was used to map contact regions in the joint of the surrogate and cadaveric cervical segments (n = 3) during extension. The probe also underwent uniaxial compression in cadaveric facets to evaluate the effect of orientation relative to the contact surface on the probe signal. Although experimental and theoretical pressure profiles followed the same trends, measured maximum pressures were half of the theoretical ones. In the orientation study, maximum pressures were not different for probe orientations of 0° and 5°, but no signal was recorded at orientations greater than 15°. This approach to measure pressure was selected to provide a minimally-invasive method to quantify facet joint pressures during clinically relevant applications. Both the position and orientation of the probe are critical factors in monitoring local pressure profiles in this mobile synovial joint.

  7. A Novel ICOS-Independent, but CD28- and SAP-Dependent, Pathway of T Cell-Dependent, Polysaccharide-Specific Humoral Immunity in Response to Intact Streptococcus pneumoniae versus Pneumococcal Conjugate Vaccine

    DTIC Science & Technology

    2008-01-01

    PPS14) and the phosphorylcholine determinant (PC) of the cell wall C-polysaccharide (C-PS, teichoic acid). The protein- and PS-specific IgG responses...hydroxy-3-nitrophenyl)acetyl; PC, phosphorylcholine determi- nant of teichoic or lipoteichoic acid; Pn, intact Streptococcus pneumoniae; PPS14, capsular

  8. Threading the Needle: Small-Molecule Targeting of a Xenobiotic Receptor to Ablate Escherichia coli Polysaccharide Capsule Expression Without Altering Antibiotic Resistance.

    PubMed

    Arshad, Mehreen; Goller, Carlos C; Pilla, Danielle; Schoenen, Frank J; Seed, Patrick C

    2016-04-15

    Uropathogenic Escherichia coli (UPEC), a leading cause of urinary tract and invasive infections worldwide, is rapidly acquiring multidrug resistance, hastening the need for selective new anti-infective agents. Here we demonstrate the molecular target of DU011, our previously discovered potent, nontoxic, small-molecule inhibitor of UPEC polysaccharide capsule biogenesis and virulence. Real-time polymerase chain reaction analysis and a target-overexpression drug-suppressor screen were used to localize the putative inhibitor target. A thermal shift assay quantified interactions between the target protein and the inhibitor, and a novel DNase protection assay measured chemical inhibition of protein-DNA interactions. Virulence of a regulatory target mutant was assessed in a murine sepsis model. MprA, a MarR family transcriptional repressor, was identified as the putative target of the DU011 inhibitor. Thermal shift measurements indicated the formation of a stable DU011-MprA complex, and DU011 abrogated MprA binding to its DNA promoter site. Knockout of mprA had effects similar to that of DU011 treatment of wild-type bacteria: a loss of encapsulation and complete attenuation in a murine sepsis model, without any negative change in antibiotic resistance. MprA regulates UPEC polysaccharide encapsulation, is essential for UPEC virulence, and can be targeted without inducing antibiotic resistance. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  9. Agrobacterium rubi(T) DSM 6772 produces a lipophilic polysaccharide capsule whose degree of acetylation is growth modulated.

    PubMed

    De Castro, Cristina; Gargiulo, Valentina; Lanzetta, Rosa; Parrilli, Michelangelo

    2007-03-01

    The structure of the capsular polysaccharide produced from the type strain of Agrobacterium rubi DSM 6772 is demonstrated by means of chemical and spectroscopical methodologies. It is constituted from the quite rare monosaccharide 6-deoxy-L-talose, involved in alternating alpha-(1 --> 2) and alpha-(1 --> 3) linkages. This simple backbone is further complicated from the occurrence of O-acetyl substituents located always at O-2 of the O-3 substituted 6-deoxy-talose. This decoration is not stoichiometric and it depends on the growth stadium of the bacterium, leading to an almost regular acetylation pattern only at the stationary phase, where all the potential positions are substituted.

  10. Sialylation of Group B Streptococcal Capsular Polysaccharide Is Mediated by cpsK and Is Required for Optimal Capsule Polymerization and Expression

    PubMed Central

    Chaffin, D. O.; Mentele, L. M.; Rubens, C. E.

    2005-01-01

    Several bacterial pathogens have evolved the means to escape immune detection by mimicking host cell surface carbohydrates that are crucial for self/non-self recognition. Sialic acid, a terminal residue on these carbohydrates, inhibits activation of the alternate pathway of complement by recruiting the immune modulating molecule factors H, I, and iC3b. Sialylation of capsular polysaccharide (CPS) is important for virulence of group B streptococci (GBS), a significant human pathogen. We previously reported that cpsK, a gene within the cps locus of type III GBS, could complement a sialyltransferase deficient lst mutant of Haemophilus ducreyi, implicating its role in sialylation of the GBS capsule. To explore the function of cpsK in GBS capsule production, we created a mutant in cpsK. Immunoblot analysis and enzyme-linked immunosorbent assay using anti-type III CPS antisera demonstrated that the mutant CPS did not contain sialic acid. This was confirmed by high-performance liquid chromatography after mild acid hydrolysis of the CPS. Although increased CPS chain length was seen for this strain, CPS production was <20% of the parental isolate. An episomal cpsK copy restored synthesis of sialo-CPS to wild-type levels. These data support our hypothesis that cpsK encodes the GBS CPS sialyltransferase and provide further evidence that lack of CPS oligosaccharide sialylation reduces the amount of CPS expressed on the cell surface. These observations also imply that one or more of the components involved in synthesis or transport of oligosaccharide repeating units requires a sialo-oligosaccharide for complete activity. PMID:15968073

  11. Distinct Mechanisms Underlie Boosted Polysaccharide-Specific IgG Responses Following Secondary Challenge with Intact Gram-Negative versus Gram-Positive Extracellular Bacteria.

    PubMed

    Kar, Swagata; Arjunaraja, Swadhinya; Akkoyunlu, Mustafa; Pier, Gerald B; Snapper, Clifford M

    2016-06-01

    Priming of mice with intact, heat-killed cells of Gram-negative Neisseria meningitidis, capsular serogroup C (MenC) or Gram-positive group B Streptococcus, capsular type III (GBS-III) bacteria resulted in augmented serum polysaccharide (PS)-specific IgG titers following booster immunization. Induction of memory required CD4(+) T cells during primary immunization. We determined whether PS-specific memory for IgG production was contained within the B cell and/or T cell populations, and whether augmented IgG responses following booster immunization were also dependent on CD4(+) T cells. Adoptive transfer of purified B cells from MenC- or GBS-III-primed, but not naive mice resulted in augmented PS-specific IgG responses following booster immunization. Similar responses were observed when cotransferred CD4(+) T cells were from primed or naive mice. Similarly, primary immunization with unencapsulated MenC or GBS-III, to potentially prime CD4(+) T cells, failed to enhance PS-specific IgG responses following booster immunization with their encapsulated isogenic partners. Furthermore, in contrast to GBS-III, depletion of CD4(+) T cells during secondary immunization with MenC or another Gram-negative bacteria, Acinetobacter baumannii, did not inhibit augmented PS-specific IgG booster responses of mice primed with heat-killed cells. Also, in contrast with GBS-III, booster immunization of MenC-primed mice with isolated MenC-PS, a TI Ag, or a conjugate of MenC-PS and tetanus toxoid elicited an augmented PS-specific IgG response similar to booster immunization with intact MenC. These data demonstrate that memory for augmented PS-specific IgG booster responses to Gram-negative and Gram-positive bacteria is contained solely within the B cell compartment, with a differential requirement for CD4(+) T cells for augmented IgG responses following booster immunization.

  12. H-NS Nucleoid Protein Controls Virulence Features of Klebsiella pneumoniae by Regulating the Expression of Type 3 Pili and the Capsule Polysaccharide

    PubMed Central

    Ares, Miguel A.; Fernández-Vázquez, José L.; Rosales-Reyes, Roberto; Jarillo-Quijada, Ma. Dolores; von Bargen, Kristine; Torres, Javier; González-y-Merchand, Jorge A.; Alcántar-Curiel, María D.; De la Cruz, Miguel A.

    2016-01-01

    Klebsiella pneumoniae is an opportunistic pathogen causing nosocomial infections. Main virulence determinants of K. pneumoniae are pili, capsular polysaccharide, lipopolysaccharide, and siderophores. The histone-like nucleoid-structuring protein (H-NS) is a pleiotropic regulator found in several gram-negative pathogens. It has functions both as an architectural component of the nucleoid and as a global regulator of gene expression. We generated a Δhns mutant and evaluated the role of the H-NS nucleoid protein on the virulence features of K. pneumoniae. A Δhns mutant down-regulated the mrkA pilin gene and biofilm formation was affected. In contrast, capsule expression was derepressed in the absence of H-NS conferring a hypermucoviscous phenotype. Moreover, H-NS deficiency affected the K. pneumoniae adherence to epithelial cells such as A549 and HeLa cells. In infection experiments using RAW264.7 and THP-1 differentiated macrophages, the Δhns mutant was less phagocytized than the wild-type strain. This phenotype was likely due to the low adherence to these phagocytic cells. Taken together, our data indicate that H-NS nucleoid protein is a crucial regulator of both T3P and CPS of K. pneumoniae. PMID:26904512

  13. H-NS Nucleoid Protein Controls Virulence Features of Klebsiella pneumoniae by Regulating the Expression of Type 3 Pili and the Capsule Polysaccharide.

    PubMed

    Ares, Miguel A; Fernández-Vázquez, José L; Rosales-Reyes, Roberto; Jarillo-Quijada, Ma Dolores; von Bargen, Kristine; Torres, Javier; González-y-Merchand, Jorge A; Alcántar-Curiel, María D; De la Cruz, Miguel A

    2016-01-01

    Klebsiella pneumoniae is an opportunistic pathogen causing nosocomial infections. Main virulence determinants of K. pneumoniae are pili, capsular polysaccharide, lipopolysaccharide, and siderophores. The histone-like nucleoid-structuring protein (H-NS) is a pleiotropic regulator found in several gram-negative pathogens. It has functions both as an architectural component of the nucleoid and as a global regulator of gene expression. We generated a Δhns mutant and evaluated the role of the H-NS nucleoid protein on the virulence features of K. pneumoniae. A Δhns mutant down-regulated the mrkA pilin gene and biofilm formation was affected. In contrast, capsule expression was derepressed in the absence of H-NS conferring a hypermucoviscous phenotype. Moreover, H-NS deficiency affected the K. pneumoniae adherence to epithelial cells such as A549 and HeLa cells. In infection experiments using RAW264.7 and THP-1 differentiated macrophages, the Δhns mutant was less phagocytized than the wild-type strain. This phenotype was likely due to the low adherence to these phagocytic cells. Taken together, our data indicate that H-NS nucleoid protein is a crucial regulator of both T3P and CPS of K. pneumoniae.

  14. Differential Regulation of IgG Anti-Capsular Polysaccharide and Antiprotein Responses to Intact Streptococcus pneumoniae in the Presence of Cognate CD4+ T Cell Help

    DTIC Science & Technology

    2004-01-01

    polysaccharide (PPS14), the phosphorylcholine determinant of the cell wall C-polysaccharide, and the cell wall protein, pneumococcal surface protein A...a more rapid delivery of CD4 T cell help. In contrast, the IgG anti- phosphorylcholine response, although also dependent on CD4 T cells, is TCR...and/or IgG isotypes specific for the phosphorylcholine (PC) determinant of the cell wall C-polysaccharide (teichoic acid) and for the cell wall

  15. High affinity mimotope of the polysaccharide capsule of Cryptococcus neoformans identified from an evolutionary phage peptide library.

    PubMed

    Beenhouwer, David O; May, Rena J; Valadon, Philippe; Scharff, Matthew D

    2002-12-15

    Cryptococcus neoformans causes a life-threatening meningoencephalitis in a significant percentage of AIDS patients. Mice immunized with a glycoconjugate vaccine composed of the glucuronoxylomannan (GXM) component of the cryptococcal capsular polysaccharide conjugated to tetanus toxoid (TT) produce Abs that, based on the epitope recognized, can be either protective or nonprotective. Since nonprotective Abs block the efficacy of protective Abs, we are interested in developing a vaccine that would focus the immune response specifically to protective epitopes. Previously, we screened a phage display library with 2H1, a protective anti-GXM mAb, and isolated PA1, a representative peptide that had a K(d) of 295 nM for 2H1. Mice immunized with PA1 conjugated to keyhole limpet hemocyanin developed high anti-peptide (1/13,000), but low anti-GXM (maximum, 1/200) titers. We now report our efforts to improve this vaccine by screening a sublibrary with six random amino acids added to either end of the PA1 motif to identify higher affinity peptides. P206.1, a peptide isolated from this sublibrary, had 80-fold higher affinity for 2H1 (K(d) = 3.7 nM) than PA1. P206.1 bound protective, but not nonprotective, anti-GXM Abs. Mice immunized with P206.1 conjugated to various carriers did not mount an Ab response to GXM despite developing high anti-peptide titers. However, mice primed with GXM-TT and boosted with P206.1-TT developed significant anti-GXM titers (maximum, 1/180,000). This latter immunization scheme focused the immune response on protective epitopes, since only 2-5% of these titers were directed against nonprotective de-O-acetylated GXM epitopes compared with 20-60% in animals primed and boosted with GXM-TT.

  16. Functional and Structural Characterization of Polysaccharide Co-polymerase Proteins Required for Polymer Export in ATP-binding Cassette Transporter-dependent Capsule Biosynthesis Pathways*

    PubMed Central

    Larue, Kane; Ford, Robert C.; Willis, Lisa M.; Whitfield, Chris

    2011-01-01

    Neisseria meningitidis serogroup B and Escherichia coli K1 bacteria produce a capsular polysaccharide (CPS) that is composed of α2,8-linked polysialic acid (PSA). Biosynthesis of PSA in these bacteria occurs via an ABC (ATP-binding cassette) transporter-dependent pathway. In N. meningitidis, export of PSA to the surface of the bacterium requires two proteins that form an ABC transporter (CtrC and CtrD) and two additional proteins, CtrA and CtrB, that are proposed to form a cell envelope-spanning export complex. CtrA is a member of the outer membrane polysaccharide export (OPX) family of proteins, which are proposed to form a pore to mediate export of CPSs across the outer membrane. CtrB is an inner membrane protein belonging to the polysaccharide co-polymerase (PCP) family. PCP proteins involved in other bacterial polysaccharide assembly systems form structures that extend into the periplasm from the inner membrane. There is currently no structural information available for PCP or OPX proteins involved in an ABC transporter-dependent CPS biosynthesis pathway to support their proposed roles in polysaccharide export. Here, we report cryo-EM images of purified CtrB reconstituted into lipid bilayers. These images contained molecular top and side views of CtrB and showed that it formed a conical oligomer that extended ∼125 Å from the membrane. This structure is consistent with CtrB functioning as a component of an envelope-spanning complex. Cross-complementation of CtrA and CtrB in E. coli mutants with defects in genes encoding the corresponding PCP and OPX proteins show that PCP-OPX pairs require interactions with their cognate partners to export polysaccharide. These experiments add further support for the model of an ABC transporter-PCP-OPX multiprotein complex that functions to export CPS across the cell envelope. PMID:21454677

  17. Biochemical And Genetic Modification Of Polysaccharides

    NASA Technical Reports Server (NTRS)

    Kern, Roger G.; Petersen, Gene R.; Richards, Gil F.

    1993-01-01

    Bacteriophages producing endopolysaccharase-type enzymes used to produce, isolate, and purify high yields of modified polysaccharides from polysaccharides produced by, and incorporated into capsules of, certain bacteria. Bacteriophages used in conversion of native polysaccharide materials into polymers of nearly uniform high molecular weight or, alternatively, into highly pure oligosaccharides. Also used in genetic selection of families of polysaccharides structurally related to native polysaccharide materials, but having altered properties. Resulting new polysaccharides and oligosaccharides prove useful in variety of products, including pharmaceutical chemicals, coating materials, biologically active carbohydrates, and drag-reducing additives for fluids.

  18. Biochemical And Genetic Modification Of Polysaccharides

    NASA Technical Reports Server (NTRS)

    Kern, Roger G.; Petersen, Gene R.; Richards, Gil F.

    1993-01-01

    Bacteriophages producing endopolysaccharase-type enzymes used to produce, isolate, and purify high yields of modified polysaccharides from polysaccharides produced by, and incorporated into capsules of, certain bacteria. Bacteriophages used in conversion of native polysaccharide materials into polymers of nearly uniform high molecular weight or, alternatively, into highly pure oligosaccharides. Also used in genetic selection of families of polysaccharides structurally related to native polysaccharide materials, but having altered properties. Resulting new polysaccharides and oligosaccharides prove useful in variety of products, including pharmaceutical chemicals, coating materials, biologically active carbohydrates, and drag-reducing additives for fluids.

  19. Differential staining of bacteria: capsule stain.

    PubMed

    Breakwell, Donald P; Moyes, Rita B; Reynolds, Jackie

    2009-11-01

    Bacterial capsules are composed of high-molecular-weight polysaccharides and/or polypeptides, and are associated with virulence and biofilm formation. Unfortunately, capsules do not stain well with crystal violet, methylene blue, or other simple stains. This unit describes two methods of capsule staining. The first is a wet-mount method using india ink; the capsule is visualized as a refractile zone surrounding a cell. The second is a direct-staining dry-mount method that precipitates copper sulfate and leaves the capsule as a pale blue zone. Both methods are easily performed within approximately 5 min.

  20. Structures of three different neutral polysaccharides of Acinetobacter baumannii, NIPH190, NIPH201, and NIPH615, assigned to K30, K45, and K48 capsule types, respectively, based on capsule biosynthesis gene clusters.

    PubMed

    Shashkov, Alexander S; Kenyon, Johanna J; Arbatsky, Nikolay P; Shneider, Mikhail M; Popova, Anastasiya V; Miroshnikov, Konstantin A; Volozhantsev, Nikolay V; Knirel, Yuriy A

    2015-11-19

    Neutral capsular polysaccharides (CPSs) were isolated from Acinetobacter baumannii NIPH190, NIPH201, and NIPH615. The CPSs were found to contain common monosaccharides only and to be branched with a side-chain 1→3-linked β-d-glucopyranose residue. Structures of the oligosaccharide repeat units (K units) of the CPSs were elucidated by 1D and 2D (1)H and (13)C NMR spectroscopy. Novel CPS biosynthesis gene clusters, designated KL30, KL45, and KL48, were found at the K locus in the genome sequences of NIPH190, NIPH201, and NIPH615, respectively. The genetic content of each gene cluster correlated with the structure of the CPS unit established, and therefore, the capsular types of the strains studied were designated as K30, K45, and K48, respectively. The initiating sugar of each K unit was predicted, and glycosyltransferases encoded by each gene cluster were assigned to the formation of the linkages between sugars in the corresponding K unit.

  1. CAPSULAR POLYSACCHARIDE OF AZOTOBACTER AGILIS.

    PubMed

    COHEN, G H; JOHNSTONE, D B

    1964-12-01

    Cohen, Gary H. (University of Vermont, Burlington), and Donald B. Johnstone. Capsular polysaccharide of Azotobacter agilis. J. Bacteriol. 88:1695-1699. 1964.-Capsular polysaccharide from Azotobacter agilis strain 132 was recovered from washed cells by alkaline digestion. The polysaccharide was purified by centrifugation, repeated alcohol precipitation, Sevag deproteinization, and treatment with ribonuclease and charcoal-cellulose. Methods of isolation and purification appeared to provide a polymer showing no evidence of heterogeneity when examined by chemical and physical methods. Colorimetric, paper chromatographic, and enzymatic analyses on both intact and acid-hydrolyzed polysaccharide indicated that the polymer contained galactose and rhamnose at a molar ratio of approximately 1.0:0.7. A sialic acid-like component was also present in the polysaccharide. The study shows significant differences in the chemical composition of the extra-cellular polysaccharide of A. agilis and that of A. vinelandii. This adds further biochemical evidence for the right of these species to independent status.

  2. The effect of glicerol and sorbitol plasticizers toward disintegration time of phyto-capsules

    NASA Astrophysics Data System (ADS)

    Pudjiastuti, Pratiwi; Hendradi, Esti; Wafiroh, Siti; Harsini, Muji; Darmokoesoemo, Handoko

    2016-03-01

    The aim of research is determining the effect of glycerol and sorbitol toward the disintegration time of phyto-capsules, originated capsules from plant polysaccharides. Phyto-capsules were made from polysaccharides and 0.5% (v/v) of glycerol and sorbitol of each. The seven capsules of each were determined the disintegration time using Erweka disintegrator. The mean of disintegration time of phyto-capsules without plasticizers, with glycerol and sorbitol were 25'30"; 45'15" and 35'30" respectively. The color and colorless gelatin capsules showed the mean of disintegration time 7'30" and 2'35" respectively.

  3. Single-Dose Pharmacokinetics of Methylphenidate Extended-Release Multiple Layer Beads Administered as Intact Capsule or Sprinkles Versus Methylphenidate Immediate-Release Tablets (Ritalin®) in Healthy Adult Volunteers

    PubMed Central

    Teuscher, Nathan S.; Kupper, Robert J.; Chang, Wei-Wei; Greenhill, Laurence; Newcorn, Jeffrey H.; Connor, Daniel F.; Wigal, Sharon

    2014-01-01

    Abstract Objectives: The purpose of this study was to evaluate the relative bioavailability and safety of a multilayer extended-release bead methylphenidate (MPH) hydrochloride 80 mg (MPH-MLR) capsule or sprinkles (37% immediate-release [IR]) versus MPH hydrochloride IR(Ritalin®) tablets, and to develop a pharmacokinetic (PK) model simulating MPH concentration-time data for different MPH-MLR dosage strengths. Methods: This was a single-center, randomized, open-label, three-period crossover study conducted in 26 fasted healthy adults (mean weight±standard deviation, 70.4±11.7 kg) assigned to single-dose oral MPH-MLR 80 mg capsule or sprinkles with applesauce, or Ritalin IR 25 mg (1×5 mg and 1×20 mg tablet) administered at 0, 4, and 8 hours. Results: MPH-MLR 80 mg capsule and sprinkles were bioequivalent; ratios for maximum concentration (Cmax), area under plasma drug concentration versus time curve (AUC)0-t, and AUC0-inf were 1.04 (95% confidence interval [CI], 96.3–112.4), 0.99 (95% CI, 95.3–102.8), and 0.99 (95% CI, 95.4–103.0), respectively. MPH-MLR capsule/sprinkles produced highly comparable, biphasic profiles of plasma MPH concentrations characterized by rapid initial peak, followed by moderate decline until 5 hours postdose, and gradual increase until 7 hours postdose, culminating in an attenuated second peak. Based on 90% CIs, total systemic exposure to MPH-MLR 80 mg capsule/sprinkles was similar to that for Ritalin IR 25 mg three times daily, but marked differences in Cmax values indicated that MPH-MLR regimens were not bioequivalent to Ritalin. MPH Cmax and total systemic exposure over the first 4 hours postdose with MPH-MLR capsule/sprinkles was markedly higher than that associated with the first dose of Ritalin. All study drugs were safe and well tolerated. The PK modeling in adults suggested that differences in MPH pharmacokinetics between MPH-MLR and Ritalin are the result of dosage form design attributes and the associated

  4. Single-dose pharmacokinetics of methylphenidate extended-release multiple layer beads administered as intact capsule or sprinkles versus methylphenidate immediate-release tablets (Ritalin(®)) in healthy adult volunteers.

    PubMed

    Adjei, Akwete; Teuscher, Nathan S; Kupper, Robert J; Chang, Wei-Wei; Greenhill, Laurence; Newcorn, Jeffrey H; Connor, Daniel F; Wigal, Sharon

    2014-12-01

    The purpose of this study was to evaluate the relative bioavailability and safety of a multilayer extended-release bead methylphenidate (MPH) hydrochloride 80 mg (MPH-MLR) capsule or sprinkles (37% immediate-release [IR]) versus MPH hydrochloride IR(Ritalin(®)) tablets, and to develop a pharmacokinetic (PK) model simulating MPH concentration-time data for different MPH-MLR dosage strengths. This was a single-center, randomized, open-label, three-period crossover study conducted in 26 fasted healthy adults (mean weight±standard deviation, 70.4±11.7 kg) assigned to single-dose oral MPH-MLR 80 mg capsule or sprinkles with applesauce, or Ritalin IR 25 mg (1×5 mg and 1×20 mg tablet) administered at 0, 4, and 8 hours. MPH-MLR 80 mg capsule and sprinkles were bioequivalent; ratios for maximum concentration (Cmax), area under plasma drug concentration versus time curve (AUC)0-t, and AUC0-inf were 1.04 (95% confidence interval [CI], 96.3-112.4), 0.99 (95% CI, 95.3-102.8), and 0.99 (95% CI, 95.4-103.0), respectively. MPH-MLR capsule/sprinkles produced highly comparable, biphasic profiles of plasma MPH concentrations characterized by rapid initial peak, followed by moderate decline until 5 hours postdose, and gradual increase until 7 hours postdose, culminating in an attenuated second peak. Based on 90% CIs, total systemic exposure to MPH-MLR 80 mg capsule/sprinkles was similar to that for Ritalin IR 25 mg three times daily, but marked differences in Cmax values indicated that MPH-MLR regimens were not bioequivalent to Ritalin. MPH Cmax and total systemic exposure over the first 4 hours postdose with MPH-MLR capsule/sprinkles was markedly higher than that associated with the first dose of Ritalin. All study drugs were safe and well tolerated. The PK modeling in adults suggested that differences in MPH pharmacokinetics between MPH-MLR and Ritalin are the result of dosage form design attributes and the associated absorption profiles of MPH. MPH-MLR 80

  5. Presence of a capsule in Neisseria lactamica, antigenically similar to the capsule of N. meningitidis.

    PubMed

    Martin, P V; Laviotola, A; Ohayon, H; Riou, J Y

    1986-01-01

    Three of thirteen strains of Neisseria lactamica, a species closely related to N. meningitidis, were selected on the basis of their ability to be strongly agglutinated by serogroup B antimeningococcal serum. The presence of a capsule was demonstrated using Alcian blue as a stain for acidic polysaccharide. When reacted with serogroup B antimeningococcal sera, 2 out of 3 N. lactamica B-coagglutanating strains exhibited an extracellular material comparable in size, antigenicity and staining properties to the capsule of serogroup B N. meningitidis.

  6. The capsule of the fungal pathogen Cryptococcus neoformans

    PubMed Central

    Zaragoza, Oscar; Rodrigues, Marcio L.; De Jesus, Magdia; Frases, Susana; Dadachova, Ekaterina; Casadevall, Arturo

    2009-01-01

    The capsule of the fungal pathogen Cryptococcus neoformans has been studied extensively in recent decades, and a large body of information is now available to the scientific community. Well-known aspects of the capsule include its structure, antigenic properties and its function as a virulence factor. The capsule is composed primarily of two polysaccharides, glucuronoxylomannan (GXM) and galactoxylomannan (GalXM), in addition to a smaller proportion of mannoproteins (MP). Most of the studies on the composition of the capsule have focused on GXM, which comprises more than 90% of the capsule's polysaccharide mass. It is GalXM, however, that is of particular scientific interest because of its immunological properties. The molecular structure of these polysaccharides is very complex and has not yet been fully elucidated. Both GXM and GalXM are high molecular mass polymers with the mass of GXM equaling roughly 10 times that of GalXM. Recent findings suggest, however, that the actual Mw might be different to what it has traditionally been thought to be. In addition to their structural roles in the polysaccharide capsule, these molecules have been associated with many deleterious effects on the immune response. Capsular components are therefore considered key virulence determinants in Cryptococcus neoformans, which has motivated their use in vaccines and made them targets for monoclonal antibody treatments. In this review we will provide an update on the current knowledge of the C. neoformans capsule, covering aspects related to its structure, synthesis, and particularly, its role as a virulence factor. PMID:19426855

  7. Antibiofilm polysaccharides

    PubMed Central

    Rendueles, Olaya; Kaplan, Jeffrey B.; Ghigo, Jean-Marc

    2012-01-01

    Summary Bacterial extracellular polysaccharides have been shown to mediate many of the cell-to cell and cell-to-surface interactions that are required for the formation, cohesion and stabilization of bacterial biofilms. However, recent studies have identified several bacterial polysaccharides that inhibit biofilm formation by a wide-spectrum of bacteria and fungi both in vitro and in vivo. This review discusses the composition, modes of action, and potential biological roles of antibiofilm polysaccharides recently identified in bacteria and eukaria. Some of these molecules may have technological applications as antibiofilm agents in industry and medicine. PMID:22730907

  8. Temperature Capsule

    NASA Technical Reports Server (NTRS)

    1992-01-01

    An ingestible mini-thermometer capable of measuring and relaying internal body temperatures is marketed by Human Technologies, Inc. The CorTemp system, developed by Goddard Space Flight Center and Applied Physics Lab, incorporates space technologies, among them telemetry and microminiaturized circuit, sensor and battery technologies. The capsule is ingested and continually monitors temperature with a vibrating quartz crystal sensor, which telemeters signals to a recorder, where data is displayed and stored. The system is very accurate, and because it does not require wires, allows patients to be monitored in everyday situations. The industrial variant (CSC-100) has wide utility in commercial applications.

  9. Spacecraft -- Capsule Separation (Animation)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for Spacecraft -- Capsule Separation animation

    This animation shows the return capsule separating from the Stardust spacecraft.

  10. Fungal polysaccharides.

    PubMed

    San-Blas, G; Suzuki, S; Hearn, V; Pinel, C; Kobayashi, H; Mendez, C; Niño, G; Nishikawa, A; San-Blas, F; Shibata, N

    1994-01-01

    Fungal polysaccharides are cell wall components which may act as antigens or as structural substrates. As antigens, the role of mannans in Saccharomyces cerevisiae and Candida albicans, and of glycoproteins in Aspergillus fumigatus are discussed. Analyses on beta-glucan synthetase in Paracoccidioides brasiliensis and the inhibitory effect of Hansenula mrakii killer toxin on beta-glucan biosynthesis are also considered.

  11. Antibiofilm Activity of Actinobacillus pleuropneumoniae Serotype 5 Capsular Polysaccharide

    PubMed Central

    Karwacki, Michael T.; Kadouri, Daniel E.; Bendaoud, Meriem; Izano, Era A.; Sampathkumar, Vandana; Inzana, Thomas J.; Kaplan, Jeffrey B.

    2013-01-01

    Cell-free extracts isolated from colony biofilms of Actinobacillus pleuropneumoniae serotype 5 were found to inhibit biofilm formation by Staphylococcus aureus, S. epidermidis and Aggregatibacter actinomycetemcomitans, but not by A. pleuropneumoniae serotype 5 itself, in a 96-well microtiter plate assay. Physical and chemical analyses indicated that the antibiofilm activity in the extract was due to high-molecular-weight polysaccharide. Extracts isolated from a mutant strain deficient in the production of serotype 5 capsular polysaccharide did not exhibit antibiofilm activity. A plasmid harboring the serotype 5 capsule genes restored the antibiofilm activity in the mutant extract. Purified serotype 5 capsular polysaccharide also exhibited antibiofilm activity against S. aureus. A. pleuropneumoniae wild-type extracts did not inhibit S. aureus growth, but did inhibit S. aureus intercellular adhesion and binding of S. aureus cells to stainless steel surfaces. Furthermore, polystyrene surfaces coated with A. pleuropneumoniae wild-type extracts, but not with capsule-mutant extracts, resisted S. aureus biofilm formation. Our findings suggest that the A. pleuropneumoniae serotype 5 capsule inhibits cell-to-cell and cell-to-surface interactions of other bacteria. A. pleuropneumoniae serotype 5 capsular polysaccharide is one of a growing number of bacterial polysaccharides that exhibit broad-spectrum, nonbiocidal antibiofilm activity. Future studies on these antibiofilm polysaccharides may uncover novel functions for bacterial polysaccharides in nature, and may lead to the development of new classes of antibiofilm agents for industrial and clinical applications. PMID:23691104

  12. BASICS OF COMPOUNDING: Capsules.

    PubMed

    Allen, Loyd V

    2016-01-01

    Capsules have been used for administering medications to patients more than a century and have an important role in drug delivery. When a primary care provider prescribes a tablet, the choice is usually, but not always, limited to commercially available products. A capsule, however, can be prepared extemporaneously, which provides dosing flexibility for the primary care provider and the pharmacist. This article discusses the definitions/types of capsules, their applications, composition, preparation, capsule sizes, the encapsulation process, capsule cleaning, physiochemical considerations, quality control in the preparation of capsules, packaging/storage, stability, and patient counseling to determine the proper capsule size. Also, provided are sample formulations.

  13. Polysaccharide Degradation

    NASA Astrophysics Data System (ADS)

    Stone, Bruce A.; Svensson, Birte; Collins, Michelle E.; Rastall, Robert A.

    An overview of current and potential enzymes used to degrade polysaccharides is presented. Such depolymerases are comprised of glycoside hydrolases, glycosyl transferases, phosphorylases and lyases, and their classification, active sites and action patterns are discussed. Additionally, the mechanisms that these enzymes use to cleave glycosidic linkages is reviewed as are inhibitors of depolymerase activity; reagents which react with amino acid residues, glycoside derivatives, transition state inhibitors and proteinaceous inhibitors. The characterization of various enzymes of microbial, animal or plant origin has led to their widespread use in the production of important oligosaccharides which can be incorporated into food stuffs. Sources of polysaccharides of particular interest in this chapter are those from plants and include inulin, dextran, xylan and pectin, as their hydrolysis products are purported to be functional foods in the context of gastrointestinal health. An alternative use of degraded polysaccharides is in the treatment of disease. The possibility exists to treat bacterial exopolysaccharide with lyases from bacteriophage to produce oligosaccharides exhibiting bioactive sequences. Although this area is currently in its infancy the knowledge is available to investigate further.

  14. Relative oral bioavailability of morphine and naltrexone derived from crushed morphine sulfate and naltrexone hydrochloride extended-release capsules versus intact product and versus naltrexone solution: a single-dose, randomized-sequence, open-label, three-way crossover trial in healthy volunteers.

    PubMed

    Johnson, Franklin K; Stark, Jeffrey G; Bieberdorf, Frederick A; Stauffer, Joe

    2010-06-01

    Morphine sulfate/sequestered naltrexone hydrochloride (HCl) (MS-sNT) extended-release fixed-dose combination capsules, approved by the US Food and Drug Administration (FDA) in August 2009 for chronic moderate to severe pain, contain extended-release morphine pellets with a sequestered core of the opioid antagonist naltrexone. MS-sNT was designed so that if the product is tampered with by crushing, the naltrexone becomes bioavailable to mitigate morphine-induced subjective effects, rendering the product less attractive for tampering. The primary aim of this study was to compare the oral bioavailability of naltrexone and its metabolite 6-beta-naltrexol, derived from crushed pellets from MS-sNT capsules, to naltrexone solution. This study also assessed the relative bioavailability of morphine from crushed pellets from MS-sNT capsules and that from the whole, intact product. This single-dose, randomized-sequence, open-label, 3-period, 3-treatment crossover trial was conducted in healthy volunteers. Adults admitted to the study center underwent a 10-hour overnight fast before study drug administration. Each subject received all 3 of the following treatments, 1 per session, separated by a 14-day washout: tampered pellets (crushed for >or=2 minutes with a mortar and pestle) from a 60-mg MS-sNT capsule (60 mg morphine/2.4 mg naltrexone); 60-mg whole, intact MS-sNT capsule; and oral naltrexone HCl (2.4 mg) solution. Plasma concentrations of naltrexone and 6-beta-naltrexol were measured 0 to 168 hours after administration. Morphine pharmaco-kinetics of crushed and whole pellets were determined 0 to 72 hours after administration. The analysis of relative bioavailability was based on conventional FDA criteria for assuming bioequivalence; that is, 90% CIs for ratios of geometric means (natural logarithm [In]-transformed C(max) and AUC) fell within the range of 80% to 125%. Subjects underwent physical examinations, clinical laboratory tests, and ECG at screening and study

  15. Structure and Composition of the Bacillus anthracis Capsule

    PubMed Central

    Avakyan, A. A.; Katz, L. N.; Levina, K. N.; Pavlova, I. B.

    1965-01-01

    Avakyan, A. A. (Academy of Medical Sciences, Moscow, USSR), L. N. Katz, K. N. Levina, and I. B. Pavlova. Structure and composition of the Bacillus anthracis capsule. J. Bacteriol. 90:1082–1095. 1965.—Observations by various methods of light microscopy (phase contrast, dark-field, and fluorescence) revealed the complex structure of the Bacillus anthracis capsule, which changes regularly during the growth cycle of the culture. Special cytological methods of staining the capsule made it possible to study its fine structure, which is not revealed by negative staining with India ink. For example, the capsule shows a membranelike outline, fine transverse lines, and interruptions and transverse septa traversing the entire capsule. By using cytochemical methods, it was found that the capsule has a stratified structure and that the various layers of the capsule differ as to the value of the isoelectric point, metachromatic ability, sensitivity to various enzymes, and, consequently, chemical composition. It was thus shown that the membranelike outline of the capsule consists of peptides and neutral mucopolysaccharides. The middle part of the capsule consists of a complex of substances of both polysaccharide and protein nature, and the inner part consists of acid mucopolysaccharides. Observation of the capsular forms of B. anthracis by means of an electron microscope revealed differences in the osmiophilia and submicroscopic structure of the membranelike outline and the middle and inner parts of the capsule. Immunochemical studies conducted by the fluorescent-antibody method revealed localization of antigens in different parts of the capsule, and made it possible to differentiate the capsular antigens according to their serum-staining ability and according of their relations to enzymes, i.e., their chemical composition. This paper concerns the possibility of studying the fine structure of bacterial capsules in fixed preparations, and the differences and similarities of

  16. Recombinant expression of Streptococcus pneumoniae capsular polysaccharides in Escherichia coli

    PubMed Central

    Kay, Emily J.; Yates, Laura E.; Terra, Vanessa S.; Cuccui, Jon; Wren, Brendan W.

    2016-01-01

    Currently, Streptococcus pneumoniae is responsible for over 14 million cases of pneumonia worldwide annually, and over 1 million deaths, the majority of them children. The major determinant for pathogenesis is a polysaccharide capsule that is variable and is used to distinguish strains based on their serotype. The capsule forms the basis of the pneumococcal polysaccharide vaccine (PPV23) that contains purified capsular polysaccharide from 23 serotypes, and the pneumococcal conjugate vaccine (PCV13), containing 13 common serotypes conjugated to CRM197 (mutant diphtheria toxin). Purified capsule from S. pneumoniae is required for pneumococcal conjugate vaccine production, and costs can be prohibitively high, limiting accessibility of the vaccine in low-income countries. In this study, we demonstrate the recombinant expression of the capsule-encoding locus from four different serotypes of S. pneumoniae within Escherichia coli. Furthermore, we attempt to identify the minimum set of genes necessary to reliably and efficiently express these capsules heterologously. These E. coli strains could be used to produce a supply of S. pneumoniae serotype-specific capsules without the need to culture pathogenic bacteria. Additionally, these strains could be applied to synthetic glycobiological applications: recombinant vaccine production using E. coli outer membrane vesicles or coupling to proteins using protein glycan coupling technology. PMID:27110302

  17. Cellular immunity to Bacteroides fragilis capsular polysaccharide

    PubMed Central

    1982-01-01

    The polysaccharide capsule of Bacteroides fragilis has been shown to be important in the virulence of the organism. The capsular polysaccharide (CP) of B. fragilis has been extensively purified. Using a murine model of intraabdominal abscess formation, we have been able to demonstrate cellular immunity to the capsular polysaccharide of B. fragilis. Immunization of C57BL/10J mice with the CP over 5 wk prevents abscess formation when the mice are challenged with B. fragilis intraperitoneally. This immunity can be transferred to naive mice with spleen cells from immune animals. The immune cells bear Thy-1.2 and Ly- 2.2 antigens. The immune response has been shown to be antigen specific, but not H-2 restricted. The possibility that these immune cells are suppressor T cells is discussed. The experimental system presented provides a model for the examination of the cellular interactions responsible for abscess formation and the cellular response to bacterial pathogens. PMID:6174672

  18. Does passage of a patency capsule indicate small-bowel patency? A prospective clinical trial?

    PubMed

    Boivin, M L; Lochs, H; Voderholzer, W A

    2005-09-01

    At many centers wireless capsule endoscopy (WCE) without prior radiographic examination to rule out relevant strictures is considered to be contraindicated in suspected obstructive small-bowel disease. However, the accuracy of radiography in this situation has often been questioned. The purpose of this prospective study was to investigate the feasibility and safety of the recently developed patency capsule, and its predictive value regarding the clinical relevance of radiographic small-bowel strictures. 22 patients with suspected obstructive small-bowel disease and/or radiological evidence of small-bowel strictures underwent a patency capsule examination. Intact passage, patient experience of pain, and capsule disintegration were correlated with radiographic findings, clinical variables, and outcome. 13 patients passed an intact capsule without complaints, despite radiographically observed small-bowel stenosis; the subsequent video capsule examination was uneventful in all. In nine patients either intact passage was painful or the capsule disintegrated; in one of these, impaction of an intact capsule led to an ileus and emergency surgery. The type of capsule passage did not correlate with radiographic presence of a stricture, underlying diagnosis, or previous surgery. There was a statistically significant correlation between outcome (surgery performed or recommended) and occurrence of painful capsule passage and disintegration ( P < or = 0.05). Painless egestion of an intact patency capsule indicates safety of WCE. Patients without obstructive symptoms require neither small-bowel radiography nor a patency capsule study prior to WCE. Disintegration of the patency capsule or painful passage seems to be associated with a clinically relevant small-bowel stricture and with a high probability of surgery.

  19. Sweat collection capsule

    NASA Technical Reports Server (NTRS)

    Delaplaine, R. W.; Greenleaf, J. E.

    1979-01-01

    Capsule, with filter paper insert, is used to collect sweat for rate monitoring, chromatographic analysis, or active sweat gland location within specified area. Construction of capsule allows change of inserts while device remains strapped in place.

  20. Effects of polysaccharides from Silene vulgaris on phagocytes.

    PubMed

    Popov, S V; Popova, G Y; Ovodova, R G; Bushneva, O A; Ovodov, Y S

    1999-09-01

    The effects of the polysaccharides isolated from the intact plant (pectic polysaccharides P1, P2 and P3) and from the callus (acidic arabinogalactan C1 and pectin C2) of Silene vulgaris on phagocytic activity were studied in relation to an uptaking capacity and a myeloperoxidase activity of the peripheral human neutrophils and monocytes and rat peritoneal macrophages in vitro. Both intact plant and callus polysaccharides were shown to increase uptaking capacity of peripheral phagocytes. The callus acidic arabinogalactan C1 was only found to stimulate lysosomal activity of the peripheral phagocytes. Some polysaccharides studied were established to effect on peritoneal resident macrophages. Pectins P1, P3 and C2 failed to enhance myeloperoxidase activity of the macrophages in calcium-free solution, whereas the effect of callus arabinogalactan C1 was established to be independent of extracellular calcium. Polysaccharides studied failed to influence neither complement receptor CR3- nor scavenger receptor SR-mediated adhesion of the macrophages. The data obtained demonstrate that the intact S. vulgaris and its callus may be used as sources of immunoactive polysaccharides and that pectins and weakly acidic arabinogalactan seemed to stimulate macrophages through different mechanisms. Complement receptor type 3 and scavenger receptor failed to mediate the cell activation induced by plant polysaccharides.

  1. Lifting Sample Return Capsule

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Stardust sample return capsule successfully landed at the U.S. Air Force Utah Test and Training Range at 2:10 a.m. Pacific time (3:10 a.m. Mountain time). The capsule contains cometary and interstellar samples gathered by the Stardust spacecraft.

    Here, the capsule is being lifted at the landing site.

  2. Streptococcus pneumoniae capsule determines disease severity in experimental pneumococcal meningitis

    PubMed Central

    Grandgirard, Denis; Valente, Luca G.; Täuber, Martin G.; Leib, Stephen L.

    2016-01-01

    Streptococcus pneumoniae bacteria can be characterized into over 90 serotypes according to the composition of their polysaccharide capsules. Some serotypes are common in nasopharyngeal carriage whereas others are associated with invasive disease, but when carriage serotypes do invade disease is often particularly severe. It is unknown whether disease severity is due directly to the capsule type or to other virulence factors. Here, we used a clinical pneumococcal isolate and its capsule-switch mutants to determine the effect of capsule, in isolation from the genetic background, on severity of meningitis in an infant rat model. We found that possession of a capsule was essential for causing meningitis. Serotype 6B caused significantly more mortality than 7F and this correlated with increased capsule thickness in the cerebrospinal fluid (CSF), a stronger inflammatory cytokine response in the CSF and ultimately more cortical brain damage. We conclude that capsule type has a direct effect on meningitis severity. This is an important consideration in the current era of vaccination targeting a subset of capsule types that causes serotype replacement. PMID:27009189

  3. Agile patency system eliminates risk of capsule retention in patients with known intestinal strictures who undergo capsule endoscopy.

    PubMed

    Herrerias, Juan M; Leighton, Jonathan A; Costamagna, Guido; Infantolino, Anthony; Eliakim, Rami; Fischer, Doron; Rubin, David T; Manten, Howard D; Scapa, Eitan; Morgan, Douglas R; Bergwerk, Ari J; Koslowsky, Binyamin; Adler, Samuel N

    2008-05-01

    Capsule endoscopy (CE) of the small bowel has become a standard diagnostic tool, but there have been concerns regarding the risk of capsule retention in certain high-risk groups. The Agile patency system, an ingestible and dissolvable capsule with an external scanner, was developed to allow physicians to perform CE with greater confidence that the capsule will be safely excreted in patients at risk for capsule retention. Our purpose was to assess the ability of the device to help physicians identify which patients with known strictures may safely undergo CE. Patients with known strictures ingested the new patency capsule and underwent periodic scanning until it was excreted. The intestinal tract was considered to be sufficiently patent if the capsule was excreted intact or if the capsule was not detected by the scanner at 30 hours after ingestion. If patency was established, then standard CE was performed. International multicenter study. A total of 106 patients with known strictures. Agile patency system. Performance and safety of Agile patency system. A total of 106 patients ingested the patency capsule. Fifty-nine (56%) excreted it intact and subsequently underwent CE. There were no cases of capsule retention. Significant findings on CE were found in 24 (41%). There were 3 severe adverse events. These results suggest that the Agile patency system is a useful tool for physicians to use before CE in patients with strictures to avoid retention. This group of patients may have a high yield of clinically significant findings at CE. This capsule may determine whether patients who have a contraindication to CE may safely undergo CE and obtain useful diagnostic information.

  4. Patency and Agile capsules.

    PubMed

    Caunedo-Alvarez, Angel; Romero-Vazquez, Javier; Herrerias-Gutierrez, Juan-M

    2008-09-14

    Small bowel strictures can be missed by current diagnostic methods. The Patency capsule is a new non-endoscopic dissolvable capsule which has as an objective of checking the patency of digestive tract, in a non-invasive manner. The available clinical trials have demonstrated that the Patency capsule is a good tool for assessment of the functional patency of the small bowel, and it allows identification of those patients who can safely undergo a capsule endoscopy, despite clinical and radiographic evidence of small-bowel obstruction. Some cases of intestinal occlusion have been reported with the Patency capsule, four of them needed surgery. So, a new capsule with two timer plugs (Agile capsule) has been recently developed in order to minimize the risk of occlusion. This new device stars its dissolution process earlier (30 h after ingestion) and its two timer plugs have been designed to begin the disintegration even when the device is blocked in a tight stricture.

  5. Stability of Betaine Capsules

    PubMed Central

    Boily, Stéphanie; Forest, Jean-Marc

    2013-01-01

    Betaine is used to treat homocystinuria and is not available in Canada as a formulated drug. In order to facilitate the administration of this compound to patients, a capsule formulation and an evaluation of its stability were required. Capsule formulations of betaine were developed (160 mg and 625 mg of betaine per capsule). As betaine has no chromophore, an HPLC-ELSD analytical method was also developed. The critical quality attributes of these formulations were evaluated (content assay, content uniformity, and dissolution) as well as their stability. Capsules with acceptable quality attributes were produced. These capsules remained stable for 1 year when stored in airtight containers at controlled room temperature. However, shelf life decreased dramatically in nonairtight containers at 30°C (3 months for the lactose-containing capsules of 160 mg and 6 months for the capsules of 625 mg). PMID:23862077

  6. CAPSULAR POLYSACCHARIDE OF AZOTOBACTER AGILIS1

    PubMed Central

    Cohen, Gary H.; Johnstone, Donald B.

    1964-01-01

    Cohen, Gary H. (University of Vermont, Burlington), and Donald B. Johnstone. Capsular polysaccharide of Azotobacter agilis. J. Bacteriol. 88:1695–1699. 1964.—Capsular polysaccharide from Azotobacter agilis strain 132 was recovered from washed cells by alkaline digestion. The polysaccharide was purified by centrifugation, repeated alcohol precipitation, Sevag deproteinization, and treatment with ribonuclease and charcoal-cellulose. Methods of isolation and purification appeared to provide a polymer showing no evidence of heterogeneity when examined by chemical and physical methods. Colorimetric, paper chromatographic, and enzymatic analyses on both intact and acid-hydrolyzed polysaccharide indicated that the polymer contained galactose and rhamnose at a molar ratio of approximately 1.0:0.7. A sialic acid-like component was also present in the polysaccharide. The study shows significant differences in the chemical composition of the extra-cellular polysaccharide of A. agilis and that of A. vinelandii. This adds further biochemical evidence for the right of these species to independent status. Images PMID:14240959

  7. Surface Polysaccharide Mutants Reveal that Absence of O Antigen Reduces Biofilm Formation of Actinobacillus pleuropneumoniae

    PubMed Central

    Hathroubi, S.; Hancock, M. A.; Langford, P. R.; Tremblay, Y. D. N.; Labrie, J.

    2015-01-01

    Actinobacillus pleuropneumoniae is a Gram-negative bacterium belonging to the Pasteurellaceae family and the causative agent of porcine pleuropneumonia, a highly contagious lung disease causing important economic losses. Surface polysaccharides, including lipopolysaccharides (LPS) and capsular polysaccharides (CPS), are implicated in the adhesion and virulence of A. pleuropneumoniae, but their role in biofilm formation is still unclear. In this study, we investigated the requirement for these surface polysaccharides in biofilm formation by A. pleuropneumoniae serotype 1. Well-characterized mutants were used: an O-antigen LPS mutant, a truncated core LPS mutant with an intact O antigen, a capsule mutant, and a poly-N-acetylglucosamine (PGA) mutant. We compared the amount of biofilm produced by the parental strain and the isogenic mutants using static and dynamic systems. Compared to the findings for the biofilm of the parental or other strains, the biofilm of the O antigen and the PGA mutants was dramatically reduced, and it had less cell-associated PGA. Real-time PCR analyses revealed a significant reduction in the level of pgaA, cpxR, and cpxA mRNA in the biofilm cells of the O-antigen mutant compared to that in the biofilm cells of the parental strain. Specific binding between PGA and LPS was consistently detected by surface plasmon resonance, but the lack of O antigen did not abolish these interactions. In conclusion, the absence of the O antigen reduces the ability of A. pleuropneumoniae to form a biofilm, and this is associated with the reduced expression and production of PGA. PMID:26483403

  8. Surface Polysaccharide Mutants Reveal that Absence of O Antigen Reduces Biofilm Formation of Actinobacillus pleuropneumoniae.

    PubMed

    Hathroubi, S; Hancock, M A; Bossé, J T; Langford, P R; Tremblay, Y D N; Labrie, J; Jacques, M

    2015-10-19

    Actinobacillus pleuropneumoniae is a Gram-negative bacterium belonging to the Pasteurellaceae family and the causative agent of porcine pleuropneumonia, a highly contagious lung disease causing important economic losses. Surface polysaccharides, including lipopolysaccharides (LPS) and capsular polysaccharides (CPS), are implicated in the adhesion and virulence of A. pleuropneumoniae, but their role in biofilm formation is still unclear. In this study, we investigated the requirement for these surface polysaccharides in biofilm formation by A. pleuropneumoniae serotype 1. Well-characterized mutants were used: an O-antigen LPS mutant, a truncated core LPS mutant with an intact O antigen, a capsule mutant, and a poly-N-acetylglucosamine (PGA) mutant. We compared the amount of biofilm produced by the parental strain and the isogenic mutants using static and dynamic systems. Compared to the findings for the biofilm of the parental or other strains, the biofilm of the O antigen and the PGA mutants was dramatically reduced, and it had less cell-associated PGA. Real-time PCR analyses revealed a significant reduction in the level of pgaA, cpxR, and cpxA mRNA in the biofilm cells of the O-antigen mutant compared to that in the biofilm cells of the parental strain. Specific binding between PGA and LPS was consistently detected by surface plasmon resonance, but the lack of O antigen did not abolish these interactions. In conclusion, the absence of the O antigen reduces the ability of A. pleuropneumoniae to form a biofilm, and this is associated with the reduced expression and production of PGA. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. The Cryptococcus neoformans Capsule: a Sword and a Shield

    PubMed Central

    O'Meara, Teresa R.

    2012-01-01

    Summary: The human fungal pathogen Cryptococcus neoformans is characterized by its ability to induce a distinct polysaccharide capsule in response to a number of host-specific environmental stimuli. The induction of capsule is a complex biological process encompassing regulation at multiple steps, including the biosynthesis, transport, and maintenance of the polysaccharide at the cell surface. By precisely regulating the composition of its cell surface and secreted polysaccharides, C. neoformans has developed intricate ways to establish chronic infection and dormancy in the human host. The plasticity of the capsule structure in response to various host conditions also underscores the complex relationship between host and parasite. Much of this precise regulation of capsule is achieved through the transcriptional responses of multiple conserved signaling pathways that have been coopted to regulate this C. neoformans-specific virulence-associated phenotype. This review focuses on specific host stimuli that trigger the activation of the signal transduction cascades and on the downstream transcriptional responses that are required for robust encapsulation around the cell. PMID:22763631

  10. Pneumococcal Capsules and Their Types: Past, Present, and Future

    PubMed Central

    Geno, K. Aaron; Gilbert, Gwendolyn L.; Song, Joon Young; Skovsted, Ian C.; Klugman, Keith P.; Jones, Christopher; Konradsen, Helle B.

    2015-01-01

    SUMMARY Streptococcus pneumoniae (the pneumococcus) is an important human pathogen. Its virulence is largely due to its polysaccharide capsule, which shields it from the host immune system, and because of this, the capsule has been extensively studied. Studies of the capsule led to the identification of DNA as the genetic material, identification of many different capsular serotypes, and identification of the serotype-specific nature of protection by adaptive immunity. Recent studies have led to the determination of capsular polysaccharide structures for many serotypes using advanced analytical technologies, complete elucidation of genetic basis for the capsular types, and the development of highly effective pneumococcal conjugate vaccines. Conjugate vaccine use has altered the serotype distribution by either serotype replacement or switching, and this has increased the need to serotype pneumococci. Due to great advances in molecular technologies and our understanding of the pneumococcal genome, molecular approaches have become powerful tools to predict pneumococcal serotypes. In addition, more-precise and -efficient serotyping methods that directly detect polysaccharide structures are emerging. These improvements in our capabilities will greatly enhance future investigations of pneumococcal epidemiology and diseases and the biology of colonization and innate immunity to pneumococcal capsules. PMID:26085553

  11. Mercury Capsule Separation Tests

    NASA Image and Video Library

    1960-04-01

    Mercury capsule separation from Redstone booster in the Altitude Wind Tunnel (AWT): NASA Lewis conducted full-scale separation tests of the posigrade rockets that were fired after the Redstone rockets burned out. The researchers studied the effect of the posigrade rockets firing on the Redstone booster and retrograde package. This film shows the Mercury capsule being mounted to the Redstone missile model in the Altitude Wind Tunnel. The capsule's engines are fired and it horizontally separates from the Atlas. After firing the capsule swings from an overhead crane.

  12. Toward an Integrated Model of Capsule Regulation in Cryptococcus neoformans

    PubMed Central

    Haynes, Brian C.; Skowyra, Michael L.; Spencer, Sarah J.; Gish, Stacey R.; Williams, Matthew; Held, Elizabeth P.; Brent, Michael R.; Doering, Tamara L.

    2011-01-01

    Cryptococcus neoformans is an opportunistic fungal pathogen that causes serious human disease in immunocompromised populations. Its polysaccharide capsule is a key virulence factor which is regulated in response to growth conditions, becoming enlarged in the context of infection. We used microarray analysis of cells stimulated to form capsule over a range of growth conditions to identify a transcriptional signature associated with capsule enlargement. The signature contains 880 genes, is enriched for genes encoding known capsule regulators, and includes many uncharacterized sequences. One uncharacterized sequence encodes a novel regulator of capsule and of fungal virulence. This factor is a homolog of the yeast protein Ada2, a member of the Spt-Ada-Gcn5 Acetyltransferase (SAGA) complex that regulates transcription of stress response genes via histone acetylation. Consistent with this homology, the C. neoformans null mutant exhibits reduced histone H3 lysine 9 acetylation. It is also defective in response to a variety of stress conditions, demonstrating phenotypes that overlap with, but are not identical to, those of other fungi with altered SAGA complexes. The mutant also exhibits significant defects in sexual development and virulence. To establish the role of Ada2 in the broader network of capsule regulation we performed RNA-Seq on strains lacking either Ada2 or one of two other capsule regulators: Cir1 and Nrg1. Analysis of the results suggested that Ada2 functions downstream of both Cir1 and Nrg1 via components of the high osmolarity glycerol (HOG) pathway. To identify direct targets of Ada2, we performed ChIP-Seq analysis of histone acetylation in the Ada2 null mutant. These studies supported the role of Ada2 in the direct regulation of capsule and mating responses and suggested that it may also play a direct role in regulating capsule-independent antiphagocytic virulence factors. These results validate our experimental approach to dissecting capsule

  13. Enzymatic Modifications of Polysaccharides

    USDA-ARS?s Scientific Manuscript database

    Polysaccharides are often modified chemically in order to improve its properties or to impart specific characteristics. Indeed quite a few commercial products are based on modified polysaccharides. In this talk, I shall describe a new set of modified polysaccharides based on enzymatic reactions. ...

  14. Biomechanical Effects of Acromioplasty on Superior Capsule Reconstruction for Irreparable Supraspinatus Tendon Tears.

    PubMed

    Mihata, Teruhisa; McGarry, Michelle H; Kahn, Timothy; Goldberg, Iliya; Neo, Masashi; Lee, Thay Q

    2016-01-01

    Acromioplasty is increasingly being performed for both reparable and irreparable rotator cuff tears. However, acromioplasty may destroy the coracoacromial arch, including the coracoacromial ligament, consequently causing a deterioration in superior stability even after superior capsule reconstruction. The purpose of this study was to investigate the effects of acromioplasty on shoulder biomechanics after superior capsule reconstruction for irreparable supraspinatus tendon tears. The hypothesis was that acromioplasty with superior capsule reconstruction would decrease the area of subacromial impingement without increasing superior translation and subacromial contact pressure. Controlled laboratory study. Seven fresh-frozen cadaveric shoulders were evaluated using a custom shoulder testing system. Glenohumeral superior translation, the location of the humeral head relative to the glenoid, and subacromial contact pressure and area were compared among 4 conditions: (1) intact shoulder, (2) irreparable supraspinatus tendon tear, (3) superior capsule reconstruction without acromioplasty, and (4) superior capsule reconstruction with acromioplasty. Superior capsule reconstruction was performed using the fascia lata. Compared with the intact shoulder, the creation of an irreparable supraspinatus tear significantly shifted the humeral head superiorly in the balanced muscle loading condition (without superior force applied) (0° of abduction: 2.8-mm superior shift [P = .0005]; 30° of abduction: 1.9-mm superior shift [P = .003]) and increased both superior translation (0° of abduction: 239% of intact [P = .04]; 30° of abduction: 199% of intact [P = .02]) and subacromial peak contact pressure (0° of abduction: 308% of intact [P = .0002]; 30° of abduction: 252% of intact [P = .001]) by applying superior force. Superior capsule reconstruction without acromioplasty significantly decreased superior translation (0° of abduction: 86% of intact [P = .02]; 30° of abduction: 75

  15. Networks of fibers and factors: regulation of capsule formation in Cryptococcus neoformans

    PubMed Central

    de S. Araújo, Glauber R.; Frases, Susana; Kronstad, James W.

    2016-01-01

    The ability of the pathogenic fungus Cryptococcus neoformans to cause life-threatening meningoencephalitis in immunocompromised individuals is due in large part to elaboration of a capsule consisting of polysaccharide fibers. The size of the cell-associated capsule is remarkably responsive to a variety of environmental and host conditions, but the mechanistic details of the regulation, synthesis, trafficking, and attachment of the polysaccharides are poorly understood. Recent studies reveal a complex network of transcription factors that influence capsule elaboration in response to several different signals of relevance to disease (e.g., iron deprivation). The emerging complexity of the network is consistent with the diversity of conditions that influence the capsule and illustrates the responsiveness of the fungus to both the environment and mammalian hosts. PMID:27516877

  16. Sample Return Capsule

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Stardust sample return capsule successfully landed at the U.S. Air Force Utah Test and Training Range at 2:10 a.m. Pacific time (3:10 a.m. Mountain time). The capsule contains cometary and interstellar samples gathered by the Stardust spacecraft.

  17. EXTRACELLULAR POLYSACCHARIDES OF AZOTOBACTER VINELANDII1

    PubMed Central

    Cohen, Gary H.; Johnstone, Donald B.

    1964-01-01

    Cohen, Gary H. (University of Vermont, Burlington), and Donald B. Johnstone. Extracellular polysaccharides of Azotobacter vinelandii. J. Bacteriol. 88:329–338. 1964.—Extracellular polysaccharides synthetized by Azotobacter vinelandii strains 155, 102, and 3A were shown to be carboxylic acid heteropolysaccharides of apparent high molecular weight. Cells were grown in a nitrogen-free, mineral broth medium with 2% sucrose. Extracellular slime was recovered by centrifugation and purified by repeated alcohol precipitation and Sevag deproteinization. Capsular polysaccharide was recovered from washed cells by mild alkaline digestion. Methods of isolation and purification appeared to provide polysaccharide showing no evidence of heterogeneity when examined by chemical and physical methods. Infrared analysis of purified slime from the three strains suggested fundamental structural similarities. Colorimetric, paper chromatographic, and enzymatic analyses on both intact and acid-hydrolyzed slime polysaccharide indicated that the polymers contained in common galacturonic acid, [α] d-glucose, and rhamnose at a ratio of approximately 43:2:1, as well as a hexuronic acid lactone, probably mannurono-lactone. However, as shown by chemical and infrared analysis, minor differences did exist; namely, slime from strain 155 and 102 contained o-acetyl groups, whereas slime from strain 3A contained none. A sialic acid-like component (1.5% of dry weight of the polysaccharide, calculated as N-acetyl neuraminic acid), was found only in the slime of strain 155. Capsular polysaccharide composition closely resembled that for slime. It is of interest that the major slime components were identical whether the energy source provided for the cells was sucrose, glucose, fructose, or ethanol. PMID:14203348

  18. NIF symmetry capsule modeling

    NASA Astrophysics Data System (ADS)

    Weber, S. V.; Casey, D. T.; Pino, J. E.; Rowley, D. P.; Smalyuk, V. A.; Spears, B. K.; Tipton, R. E.

    2013-10-01

    NIF CH ablator symmetry capsules are filled with hydrogen or helium gas. SymCaps have more moderate convergence ratios ~ 15 as opposed to ~ 35 for ignition capsules with DT ice layers, and better agreement has been achieved between simulations and experimental data. We will present modeling of capsules with CD layers and tritium fill, for which we are able to match the dependence of DT yield on recession distance of the CD layer from the gas. We can also match the performance of CH capsules with D3 He fill. The simulations include surface roughness, drive asymmetry, a mock-up of modulation introduced by the tent holding the capsule, and an empirical prescription for ablator-gas atomic mix. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  19. Masquerading microbial pathogens: Capsular polysaccharides mimic host-tissue molecules

    PubMed Central

    Cress, Brady F.; Englaender, Jacob A.; He, Wenqin; Kasper, Dennis; Linhardt, Robert J.; Koffas, Mattheos A. G.

    2014-01-01

    Summary Bacterial pathogens bearing capsular polysaccharides identical to mammalian glycans benefit from an additional level of protection from host immune response. The increasing prevalence of antibiotic resistant bacteria portends an impending post-antibiotic age, characterized by diminishing efficacy of common antibiotics and routine application of multifaceted, complementary therapeutic approaches to treat bacterial infections, particularly multidrug-resistant organisms. The first line of defense for most bacterial pathogens consists of a physical and immunological barrier known as the capsule, commonly composed of a viscous layer of carbohydrates that are covalently bound to the cell wall in Gram-positive bacteria or often to lipids of the outer membrane in many Gram-negative bacteria. Bacterial capsular polysaccharides are a diverse class of high molecular weight polysaccharides contributing to virulence of many human pathogens in the gut, respiratory tree, urinary tract, and other host tissues, by hiding cell-surface components that might otherwise elicit host immune response. This review highlights capsular polysaccharides that are structurally identical or similar to polysaccharides found in mammalian tissues, including polysialic acid and glycosaminoglycan capsules hyaluronan, heparosan, and chondroitin. Such non-immunogenic coatings render pathogens insensitive to certain immune responses, effectively increasing residence time in host tissues and enabling pathologically relevant population densities to be reached. Biosynthetic pathways and capsular involvement in immune system evasion are described providing a basis for potential therapies aimed at supplementing or replacing antibiotic treatment. PMID:24372337

  20. Method for producing capsular polysaccharides

    NASA Technical Reports Server (NTRS)

    Kern, Roger G. (Inventor); Petersen, Gene R. (Inventor); Richards, Gil F. (Inventor)

    1994-01-01

    Structurally altered capsular polysaccharides are produced by mutant bacteria. These polysaccharides are isolated by selecting a wild type bacterial strain and a phage producing degradative enzymes that have substrate specificity for the capsular polysaccharides produced by the wild type bacteria. Phage-resistant mutants producing capsular polysaccharides are selected and the structurally altered capsular polysaccharide is isolated therefrom.

  1. Planktonic/sessile dimorphism of polysaccharide-encapsulated sphingomonads.

    PubMed

    Pollock, T J; Armentrout, R W

    1999-10-01

    Sphingomonads have acquired diverse metabolic activities to inhabit a wide range of environments. Several strains of Sphingomonas display phenotypic dimorphism and can adopt either a planktonic or sessile behavior in liquid media. The sessile state is marked by the presence of a viscous exopolysaccharide capsule. Specific types of these capsular polysaccharides are harvested from large-scale fermentations for use as rheology modifiers in many industrial and food applications. Sensing of environmental stimuli and genetic control over synthesis of the capsule are key events in alternating between these two phenotypes.

  2. The Lens Capsule

    PubMed Central

    Danysh, Brian P.; Duncan, Melinda K.

    2009-01-01

    The lens capsule is a modified basement membrane that completely surrounds the ocular lens. It is known that this extracellular matrix is important for both the structure and biomechanics of the lens in addition to providing informational cues to maintain lens cell phenotype. This review covers the development and structure of the lens capsule, lens diseases associated with mutations in extracellular matrix genes and the role of the capsule in lens function including those proposed for visual accommodation, selective permeability to infectious agents, and cell signaling. PMID:18773892

  3. Chemical Modification of Polysaccharides

    PubMed Central

    Cumpstey, Ian

    2013-01-01

    This review covers methods for modifying the structures of polysaccharides. The introduction of hydrophobic, acidic, basic, or other functionality into polysaccharide structures can alter the properties of materials based on these substances. The development of chemical methods to achieve this aim is an ongoing area of research that is expected to become more important as the emphasis on using renewable starting materials and sustainable processes increases in the future. The methods covered in this review include ester and ether formation using saccharide oxygen nucleophiles, including enzymatic reactions and aspects of regioselectivity; the introduction of heteroatomic nucleophiles into polysaccharide chains; the oxidation of polysaccharides, including oxidative glycol cleavage, chemical oxidation of primary alcohols to carboxylic acids, and enzymatic oxidation of primary alcohols to aldehydes; reactions of uronic-acid-based polysaccharides; nucleophilic reactions of the amines of chitosan; and the formation of unsaturated polysaccharide derivatives. PMID:24151557

  4. Alkaline phosphatase encapsulated in gellan-chitosan hybrid capsules.

    PubMed

    Fujii, Toshihiro; Ogiwara, Daisuke; Ohkawa, Kousaku; Yamamoto, Hiroyuki

    2005-05-23

    Alkaline phosphatase (ALP) was encapsulated in gellan-chitosan polyion complex (PIC) capsules using a convenient procedure. The recovery of ALP was about 50% when the capsules were prepared by dropping a solution of ALP and gellan mixture (ALP/gellan) into a chitosan solution. When p-nitrophenyl phosphate (p-NPP) and 5-bromo-4-chloro-3-indolyl phosphate (BCIP) were incubated with ALP/gellan-chitosan capsules as substrates for ALP, the transparent colorless capsules changed to yellow and blue, respectively. The encapsulation of ALP into the PIC capsules was also confirmed by SDS-PAGE and immunoblot analyses. The ALP and polypeptides of more than 30 kDa remained without release even after incubation at 4 degrees C for 14 d. The biochemical properties of the encapsulated ALP activity were similar to those of the intact enzyme. When the solution containing p-NPP was loaded on a column packed with ALP/gellan-chitosan capsules at 27 degrees C, approximately 75% of p-NPP was hydrolyzed by passing through the column. No significant leakage of ALP was observed during the procedure, indicating that the capsules were resistant to pressure in the chromatographic operation. Furthermore, 70% of the hydrolytic activity of the packed capsules remained after storage at 4 degrees C for one month. These results suggest that the polyion complex capsules could be useful materials for protein fixation without chemical modification. [Diagram: see text] Encapsulation of ALP into PIC capsules and the morphological changes seen in the absence of the ALP substrate and in the presence of p-NPP and BICP.

  5. The Cryptococcus neoformans capsule: lessons from the use of optical tweezers and other biophysical tools

    PubMed Central

    Pontes, Bruno; Frases, Susana

    2015-01-01

    The fungal pathogen Cryptococcus neoformans causes life-threatening infections in immunocompromised individuals, representing one of the leading causes of morbidity and mortality in AIDS patients. The main virulence factor of C. neoformans is the polysaccharide capsule; however, many fundamental aspects of capsule structure and function remain poorly understood. Recently, important capsule properties were uncovered using optical tweezers and other biophysical techniques, including dynamic and static light scattering, zeta potential and viscosity analysis. This review provides an overview of the latest findings in this emerging field, explaining the impact of these findings on our understanding of C. neoformans biology and resistance to host immune defenses. PMID:26157436

  6. The Cryptococcus neoformans capsule: lessons from the use of optical tweezers and other biophysical tools.

    PubMed

    Pontes, Bruno; Frases, Susana

    2015-01-01

    The fungal pathogen Cryptococcus neoformans causes life-threatening infections in immunocompromised individuals, representing one of the leading causes of morbidity and mortality in AIDS patients. The main virulence factor of C. neoformans is the polysaccharide capsule; however, many fundamental aspects of capsule structure and function remain poorly understood. Recently, important capsule properties were uncovered using optical tweezers and other biophysical techniques, including dynamic and static light scattering, zeta potential and viscosity analysis. This review provides an overview of the latest findings in this emerging field, explaining the impact of these findings on our understanding of C. neoformans biology and resistance to host immune defenses.

  7. Stennis time capsule

    NASA Image and Video Library

    2011-10-15

    Stennis Space Center Director Patrick Scheuermann (right) and Naval Meteorology and Oceanography Command Chief of Staff James Pettigrew drop the first shovelfuls of dirt on a time capsule to be opened on the rocket engine test facility's 100th anniversary in 2061. The time capsule was placed in front of the Roy S. Estess Building on Oct. 25 as Stennis concluded celebrations of its 50th anniversary. NASA publicly announced plans to build the rocket engine test site Oct. 25, 1961.

  8. Stennis time capsule

    NASA Image and Video Library

    2011-10-15

    Stennis Space Center Director Patrick Scheuermann (right) and Naval Meteorology and Oceanography Command Chief of Staff James Pettigrew drop the first shovelfuls of dirt on a time capsule to be opened on the rocket engine test facility's 100th anniversary in 2061. The time capsule was placed in front of the Roy S. Estess Building on Oct. 25 as Stennis concluded celebrations of its 50th anniversary.

  9. Evasion of Innate Immune Responses by the Highly Virulent Cryptococcus gattii by Altering Capsule Glucuronoxylomannan Structure

    PubMed Central

    Urai, Makoto; Kaneko, Yukihiro; Ueno, Keigo; Okubo, Yoichiro; Aizawa, Tomoko; Fukazawa, Hidesuke; Sugita, Takashi; Ohno, Hideaki; Shibuya, Kazutoshi; Kinjo, Yuki; Miyazaki, Yoshitsugu

    2016-01-01

    Cryptococcus neoformans causes life-threatening diseases mainly in immunosuppressed hosts such as AIDS patients; C. gattii causes disseminated infections even in healthy hosts. To identify the possible molecular mechanisms underlying this difference in virulence, we investigated the survival and histopathology of lung tissue in wild-type and CD4-depleted mice infected with C. neoformans H99 and C. gattii JP02 (the highly virulent strain isolated in Japan); we then compared dendritic cell (DC) cytokine release responses to different cell fractions from these two strains. JP02-infected mice exhibited shorter survival and fewer inflammatory cells in the lung than H99-infected control mice. Depletion of CD4-related cellular immunity reduced survival of H99-infected mice but had no effect on the survival or inflammatory cell infiltration in JP02-infected mice, suggesting that JP02 evades immune detection. To identify the molecule(s) conferring this difference, we measured cytokine production from murine DCs co-cultured with H99 and JP02 in vitro. The levels of inflammatory cytokines from DCs treated with intact JP02 cells, the extracted capsule, secreted extracellular polysaccharides, and purified glucuronoxylomannan (GXM) were markedly lower than those induced by intact H99 cells and corresponding H99 fractions. Structural analysis of GXM indicated that JP02 altered one of two O-acetyl groups detected in the H99 GXM. Deacetylated GXM lost the ability to induce inflammatory cytokine release from DCs, implicating these O-acetyl groups in immune recognition. We conclude that the highly virulent C. gattii processes a structural alteration in GXM that allows this pathogen to evade the immune response and therefore elimination. PMID:26779451

  10. Evasion of Innate Immune Responses by the Highly Virulent Cryptococcus gattii by Altering Capsule Glucuronoxylomannan Structure.

    PubMed

    Urai, Makoto; Kaneko, Yukihiro; Ueno, Keigo; Okubo, Yoichiro; Aizawa, Tomoko; Fukazawa, Hidesuke; Sugita, Takashi; Ohno, Hideaki; Shibuya, Kazutoshi; Kinjo, Yuki; Miyazaki, Yoshitsugu

    2015-01-01

    Cryptococcus neoformans causes life-threatening diseases mainly in immunosuppressed hosts such as AIDS patients; C. gattii causes disseminated infections even in healthy hosts. To identify the possible molecular mechanisms underlying this difference in virulence, we investigated the survival and histopathology of lung tissue in wild-type and CD4-depleted mice infected with C. neoformans H99 and C. gattii JP02 (the highly virulent strain isolated in Japan); we then compared dendritic cell (DC) cytokine release responses to different cell fractions from these two strains. JP02-infected mice exhibited shorter survival and fewer inflammatory cells in the lung than H99-infected control mice. Depletion of CD4-related cellular immunity reduced survival of H99-infected mice but had no effect on the survival or inflammatory cell infiltration in JP02-infected mice, suggesting that JP02 evades immune detection. To identify the molecule(s) conferring this difference, we measured cytokine production from murine DCs co-cultured with H99 and JP02 in vitro. The levels of inflammatory cytokines from DCs treated with intact JP02 cells, the extracted capsule, secreted extracellular polysaccharides, and purified glucuronoxylomannan (GXM) were markedly lower than those induced by intact H99 cells and corresponding H99 fractions. Structural analysis of GXM indicated that JP02 altered one of two O-acetyl groups detected in the H99 GXM. Deacetylated GXM lost the ability to induce inflammatory cytokine release from DCs, implicating these O-acetyl groups in immune recognition. We conclude that the highly virulent C. gattii processes a structural alteration in GXM that allows this pathogen to evade the immune response and therefore elimination.

  11. Cryptococcus neoformans capsular polysaccharides form branched and complex filamentous networks viewed by high-resolution microscopy.

    PubMed

    Araújo, Glauber R de S; Fontes, Giselle N; Leão, Daniela; Rocha, Gustavo Miranda; Pontes, Bruno; Sant'Anna, Celso; de Souza, Wanderley; Frases, Susana

    2016-01-01

    Cryptococcus neoformans is a fungal pathogen that causes life-threatening infections in immunocompromised individuals. Its main virulence factor is an extracellular polysaccharide capsule whose structure, assembly and dynamics remain poorly understood. In this study, we apply improved protocols for sample preparation and recently-developed scanning microscopy techniques to visualize the ultrastructure of the C. neoformans capsule at high-resolution (up to 1 nm) and improved structural preservation. Although most capsule structures in nature consist of linear polymers, we show here that the C. neoformans capsule is a 'microgel-like' structure composed of branched polysaccharides. Moreover, we imaged the capsule-to-cell wall link, which is formed by thin fibers that branch out of thicker capsule filaments, and have one end firmly embedded in the cell wall structure. Together, our findings provide compelling ultrastructural evidence for a branched and complex capsule conformation, which may have important implications for the biological activity of the capsule as a virulence factor. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Production of Extracellular Polysaccharide by Zoogloea ramigera

    PubMed Central

    Norberg, Anders B.; Enfors, Sven-Olof

    1982-01-01

    In batch cultures of Zoogloea ramigera the maximum rate of exopolysaccharide synthesis occurred in a partly growth-linked process. The exopolysaccharide was attached to the cells as a capsule. The capsules were released from the cell walls after 150 h of cultivation, which caused the fermentation broth to be highly viscous. Ultrasonication could be used to release capsular polysaccharide from the microbial cell walls. Treatment performed after 48 to 66 h of cultivation revealed exopolysaccharide concentration and apparent viscosity values in accordance with values of untreated samples withdrawn after 161 h of cultivation. The yield coefficient of exopolysaccharide on the basis of consumed glucose was in the range of 55 to 60% for batch cultivations with an initial glucose concentration of 25 g liter−1. An exopolysaccharide concentration of up to 38 g liter−1 could be attained if glucose, nitrogen, and growth factors were fed into the batch culture. The oxygen consumption rate in batch fermentations reached 25 mmol of O2 liter−1 h−1 during the exopolysaccharide synthesis phase and then decreased to values below 5 mmol of O2 liter−1 h−1 during the release phase. The fermentation broth showed pseudoplastic flow behavior, and the polysaccharide was not degraded when growth had ceased. Images PMID:16346138

  13. Production of Extracellular Polysaccharide by Zoogloea ramigera.

    PubMed

    Norberg, A B; Enfors, S O

    1982-11-01

    In batch cultures of Zoogloea ramigera the maximum rate of exopolysaccharide synthesis occurred in a partly growth-linked process. The exopolysaccharide was attached to the cells as a capsule. The capsules were released from the cell walls after 150 h of cultivation, which caused the fermentation broth to be highly viscous. Ultrasonication could be used to release capsular polysaccharide from the microbial cell walls. Treatment performed after 48 to 66 h of cultivation revealed exopolysaccharide concentration and apparent viscosity values in accordance with values of untreated samples withdrawn after 161 h of cultivation. The yield coefficient of exopolysaccharide on the basis of consumed glucose was in the range of 55 to 60% for batch cultivations with an initial glucose concentration of 25 g liter. An exopolysaccharide concentration of up to 38 g liter could be attained if glucose, nitrogen, and growth factors were fed into the batch culture. The oxygen consumption rate in batch fermentations reached 25 mmol of O(2) liter h during the exopolysaccharide synthesis phase and then decreased to values below 5 mmol of O(2) liter h during the release phase. The fermentation broth showed pseudoplastic flow behavior, and the polysaccharide was not degraded when growth had ceased.

  14. Variation at the capsule locus, cps, of mistyped and non-typable Streptococcus pneumoniae isolates.

    PubMed

    Salter, S J; Hinds, J; Gould, K A; Lambertsen, L; Hanage, W P; Antonio, M; Turner, P; Hermans, P W M; Bootsma, H J; O'Brien, K L; Bentley, S D

    2012-06-01

    The capsule polysaccharide locus (cps) is the site of the capsule biosynthesis gene cluster in encapsulated Streptococcus pneumoniae. A set of pneumococcal samples and non-pneumococcal streptococci from Denmark, the Gambia, the Netherlands, Thailand, the UK and the USA were sequenced at the cps locus to elucidate serologically mistyped or non-typable isolates. We identified a novel serotype 33B/33C mosaic capsule cluster and previously unseen serotype 22F capsule genes, disrupted and deleted cps clusters, the presence of aliB and nspA genes that are unrelated to capsule production, and similar genes in the non-pneumococcal samples. These data provide greater understanding of diversity at a locus which is crucial to the antigenic diversity of the pathogen and current vaccine strategies.

  15. κ-Carrageenan/locust bean gum as hard capsule gelling agents.

    PubMed

    He, Huanghuang; Ye, Jing; Zhang, Xueqin; Huang, Yayan; Li, Xiaohui; Xiao, Meitian

    2017-11-01

    A novel gelling agent, comprising blended κ-carrageenan (κ-C), a seaweed polysaccharide and locust bean gum (LBG), was used to prepare hard capsules. The distinct synergism between κ-C and LBG were verified by the textural profile analysis (TPA), FTIR and rheological measurement. Afterwards, films and hard capsules were prepared with the optimized LBG/κ-C blend gel. And the mechanical properties and morphology of films and hard capsules were analyzed by tensile testing and SEM, respectively. The results showed that the LBG/κ-C at 1:3 ratio could serve as an excellent gelling agent, which endowed hard capsule with the promoted mechanical properties, homogenous and smooth surface morphology. This work suggests that a novel blended LBG/κ-C gelling agent successfully prepared for hard capsules with improving physicochemical properties. Copyright © 2017. Published by Elsevier Ltd.

  16. Laser tissue interaction in the porcine otic capsule tissue model

    NASA Astrophysics Data System (ADS)

    Wong, Brian J.; Lee, Jon P.; Berns, Michael W.; White, Joel M.; Neev, Joseph

    1996-01-01

    The absence of a hard tissue model reflecting the properties of the inner and middle ear has made it difficult to draw consistent conclusions on the many experimental laser studies in ear surgery. Porcine otic capsule tissue has been studied by our group extensively in a wide variety of laser-tissue interaction studies and is an economically attractive and simple to use hard tissue source. Porcine otic capsule was harvested from the temporal bone of freshly sacrificed domestic pigs via a craniotomy approach. The technique when performed with power instruments takes less than 5 minutes and the entire otic capsule bone is removed intact as the suture line is not fused to the remaining petrous apex. The tissue specimen contains a vestibule, cochlea, oval and round windows, and internal auditory canals which can be used as an intact middle ear/inner ear system. The tissue can also be micromachined into thin slabs of bone varying for 100 - 1000 micrometers in thickness. In order to quantify more precisely the laser-tissue interactions in otic capsule, optical properties (absorption and scattering) and physical properties were determined (acoustic impedance). The tissue has been used in a wide variety of basic studies investigating the laser-tissue interactions with argon, KTP, (Nd:YAG), carbon dioxide, Ho:YAG, Er:YAG, and XeCl lasers. Porcine otic capsule is an ideal tissue on which standardized test can be performed to compare the relative effects of various laser in otosurgical models.

  17. Polysaccharide-Based Vaccines

    NASA Astrophysics Data System (ADS)

    Santana, Violeta Fernández; Balbin, Yury Valdés; Calderón, Janoi Chang; Icart, Luis Peña; Verez-Bencomo, Vicente

    Capsular polysaccharides (CPS) and lipopolysaccharides from bacteria are employed for the production of vaccines against human diseases. Initial development of CPS as a vaccine was followed by the development and introduction of conjugate polysaccharide-protein vaccines. The principles leading to both developments are reviewed.

  18. Modulation of surgical fibrosis by microbial zwitterionic polysaccharides

    NASA Astrophysics Data System (ADS)

    Ruiz-Perez, Begonia; Chung, Doo R.; Sharpe, Arlene H.; Yagita, Hideo; Kalka-Moll, Wiltrud M.; Sayegh, Mohamed H.; Kasper, Dennis L.; Tzianabos, Arthur O.

    2005-11-01

    Bacterial carbohydrates have long been considered T cell-independent antigens that primarily induce humoral immune responses. Recently, it has been demonstrated that bacterial capsules that possess a zwitterionic charge motif can activate CD4+ T cells after processing and presentation by antigen-presenting cells. Here we show that these zwitterionic polysaccharides can prevent T helper 1-mediated fibrosis by signaling for the release of IL-10 from CD4+ T cells in vivo. IL-10 production by these T cells and their ability to prevent fibrosis is controlled by the inducible costimulator (ICOS)-ICOS ligand pathway. These data demonstrate that the interaction of the zwitterionic polysaccharides with T cells results in modulation of surgical fibrosis in vivo and suggest a previously undescribed approach to "harnessing" T cell function to prevent inflammatory tissue disorders in humans. IL-10 | microbial polysaccharides | inducible costimulator

  19. Advances in Capsule Endoscopy

    PubMed Central

    Scott, Ryan

    2015-01-01

    Wireless video capsule endoscopy (VCE) is a minimally invasive technology that has revolutionized the approach to small intestinal disease investigation and management. Designed primarily to provide diagnostic imaging of the small intestine, VCE is used predominantly for obscure gastrointestinal bleeding and suspected Crohn’s disease; however, numerous other indications have been established, including the assessment of celiac disease, investigation of small bowel tumors, and surveillance of hereditary polyposis syndromes. Since the introduction of small bowel VCE in 2000, more than 1600 articles have been published describing the evolution of this technology. The main adverse outcome is capsule retention, which can potentially be avoided by careful patient selection or by using a patency capsule. Despite the numerous advances in the past 15 years, limitations such as incomplete VCE studies, missed lesions, and time-consuming reporting remain. The inability to control capsule movement for the application of targeted therapy or the acquisition of tissue for histologic analysis remains among the greatest challenges in the further development of capsule technology. This article outlines the recent technological and clinical advances in VCE and the future directions of research in this field. PMID:27482183

  20. Advances in Capsule Endoscopy.

    PubMed

    Scott, Ryan; Enns, Robert

    2015-09-01

    Wireless video capsule endoscopy (VCE) is a minimally invasive technology that has revolutionized the approach to small intestinal disease investigation and management. Designed primarily to provide diagnostic imaging of the small intestine, VCE is used predominantly for obscure gastrointestinal bleeding and suspected Crohn's disease; however, numerous other indications have been established, including the assessment of celiac disease, investigation of small bowel tumors, and surveillance of hereditary polyposis syndromes. Since the introduction of small bowel VCE in 2000, more than 1600 articles have been published describing the evolution of this technology. The main adverse outcome is capsule retention, which can potentially be avoided by careful patient selection or by using a patency capsule. Despite the numerous advances in the past 15 years, limitations such as incomplete VCE studies, missed lesions, and time-consuming reporting remain. The inability to control capsule movement for the application of targeted therapy or the acquisition of tissue for histologic analysis remains among the greatest challenges in the further development of capsule technology. This article outlines the recent technological and clinical advances in VCE and the future directions of research in this field.

  1. Encapsulation of active ingredients in polysaccharide-protein complex coacervates.

    PubMed

    Devi, Nirmala; Sarmah, Mandip; Khatun, Bably; Maji, Tarun K

    2017-01-01

    Polysaccharide-protein complex coacervates are amongst the leading pair of biopolymer systems that has been used over the past decades for encapsulation of numerous active ingredients. Complex coacervation of polysaccharides and proteins has received increasing research interest for the practical application in encapsulation industry since the pioneering work of complex coacervation by Bungenburg de Jong and co-workers on the system of gelatin-acacia, a protein-polysaccharide system. Because of the versatility and numerous potential applications of these systems essentially in the fields of food, pharmaceutical, cosmetics and agriculture, there has been intense interest in recent years for both fundamental and applied studies. Precisely, the designing of the micronscale and nanoscale capsules for encapsulation and control over their properties for practical applications garners renewed interest. This review discusses on the overview of polysaccharide-protein complex coacervates and their use for the encapsulation of diverse active ingredients, designing and controlling of the capsules for delivery systems and developments in the area. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Marine Origin Polysaccharides in Drug Delivery Systems.

    PubMed

    Cardoso, Matias J; Costa, Rui R; Mano, João F

    2016-02-05

    Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents and extraction media, and their interaction with other biocompounds. Polysaccharides such as alginate, carrageenan and fucoidan can be extracted from algae, whereas chitosan and hyaluronan can be obtained from animal sources. Most marine polysaccharides have important biological properties such as biocompatibility, biodegradability, and anti-inflammatory activity, as well as adhesive and antimicrobial actions. Moreover, they can be modified in order to allow processing them into various shapes and sizes and may exhibit response dependence to external stimuli, such as pH and temperature. Due to these properties, these biomaterials have been studied as raw material for the construction of carrier devices for drugs, including particles, capsules and hydrogels. The devices are designed to achieve a controlled release of therapeutic agents in an attempt to fight against serious diseases, and to be used in advanced therapies, such as gene delivery or regenerative medicine.

  3. Marine Origin Polysaccharides in Drug Delivery Systems

    PubMed Central

    Cardoso, Matias J.; Costa, Rui R.; Mano, João F.

    2016-01-01

    Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents and extraction media, and their interaction with other biocompounds. Polysaccharides such as alginate, carrageenan and fucoidan can be extracted from algae, whereas chitosan and hyaluronan can be obtained from animal sources. Most marine polysaccharides have important biological properties such as biocompatibility, biodegradability, and anti-inflammatory activity, as well as adhesive and antimicrobial actions. Moreover, they can be modified in order to allow processing them into various shapes and sizes and may exhibit response dependence to external stimuli, such as pH and temperature. Due to these properties, these biomaterials have been studied as raw material for the construction of carrier devices for drugs, including particles, capsules and hydrogels. The devices are designed to achieve a controlled release of therapeutic agents in an attempt to fight against serious diseases, and to be used in advanced therapies, such as gene delivery or regenerative medicine. PMID:26861358

  4. The diversity of Klebsiella pneumoniae surface polysaccharides

    PubMed Central

    Heinz, Eva; Wyres, Kelly L.; Ellington, Matthew J.; Kowarik, Michael; Holt, Kathryn E.; Thomson, Nicholas R.

    2016-01-01

    Klebsiella pneumoniae is considered an urgent health concern due to the emergence of multi-drug-resistant strains for which vaccination offers a potential remedy. Vaccines based on surface polysaccharides are highly promising but need to address the high diversity of surface-exposed polysaccharides, synthesized as O-antigens (lipopolysaccharide, LPS) and K-antigens (capsule polysaccharide, CPS), present in K. pneumoniae. We present a comprehensive and clinically relevant study of the diversity of O- and K-antigen biosynthesis gene clusters across a global collection of over 500 K. pneumoniae whole-genome sequences and the seroepidemiology of human isolates from different infection types. Our study defines the genetic diversity of O- and K-antigen biosynthesis cluster sequences across this collection, identifying sequences for known serotypes as well as identifying novel LPS and CPS gene clusters found in circulating contemporary isolates. Serotypes O1, O2 and O3 were most prevalent in our sample set, accounting for approximately 80 % of all infections. In contrast, K serotypes showed an order of magnitude higher diversity and differ among infection types. In addition we investigated a potential association of O or K serotypes with phylogenetic lineage, infection type and the presence of known virulence genes. K1 and K2 serotypes, which are associated with hypervirulent K. pneumoniae, were associated with a higher abundance of virulence genes and more diverse O serotypes compared to other common K serotypes. PMID:28348868

  5. Coaxial atomizer liquid intact lengths

    NASA Technical Reports Server (NTRS)

    Eroglu, Hasan; Chigier, Norman; Farago, Zoltan

    1991-01-01

    Average intact lengths of round liquid jets generated by airblast coaxial atomizer were measured from over 1500 photographs. The intact lengths were studied over a jet Reynolds number range of 18,000 and Weber number range of 260. Results are presented for two different nozzle geometries. The intact lengths were found to be strongly dependent on Re and We numbers. An empirical equation was derived as a function of these parameters. A comparison of the intact lengths for round jets and flat sheets shows that round jets generate shorter intact lengths.

  6. Hollow Microporous Organic Capsules

    PubMed Central

    Li, Buyi; Yang, Xinjia; Xia, Lingling; Majeed, Muhammad Irfan; Tan, Bien

    2013-01-01

    Fabrication of hollow microporous organic capsules (HMOCs) could be very useful because of their hollow and porous morphology, which combines the advantages of both microporous organic polymers and non-porous nanocapsules. They can be used as storage materials or reaction chambers while supplying the necessary path for the design of controlled uptake/release systems. Herein, the synthesis of HMOCs with high surface area through facile emulsion polymerization and hypercrosslinking reactions, is described. Due to their tailored porous structure, these capsules possessed high drug loading efficiency, zero-order drug release kinetics and are also demonstrated to be used as nanoscale reactors for the prepareation of nanoparticles (NPs) without any external stabilizer. Moreover, owing to their intrinsic biocompatibility and fluorescence, these capsules exhibit promising prospect for biomedical applications. PMID:23820511

  7. (Photosynthesis in intact plants)

    SciTech Connect

    Not Available

    1990-01-01

    Progress in the two years since the last renewal application has been excellent. We have made substantial contributions on both main fronts of the projects, and are particularly happy with the progress of our research on intact plants. The approach of basing our field work on a sound foundation of laboratory studies has enabled is to use methods which provide unambiguous assays of well characterized reactions. We have also made excellent progress in several laboratory studies which will have direct applications in future field work, and have introduced to the laboratory a range of molecular genetics techniques which will allow us to explore new options in the attempt to understand function at the level of molecular structure.

  8. Stardust Capsule Return

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Stardust Capsule Return as seen from NASA's DC-8 Airborne Laboratory with a mission to explore the conditions during reentry from the light emitted by the fireball caused when the capsule streaked through the sky. The aircraft was located near the end of the trajectory, just outside of UTTR. The participating researchers are from NASA Ames, the SETI Institute, the University of Alaska, Utah State University, Lockheed Martin, U.S. Air Force Academy, the University of Kobe (Japan), and Stuttgart University (Germany).

  9. Gelatin capsule in stomach (image)

    MedlinePlus

    ... detect the presence of intestinal parasites. A weighted gelatin capsule attached to a string is swallowed and left in place. After about 4 hours, the gelatin capsule is pulled out of the stomach by ...

  10. Big Joe Capsule Assembly Activities

    NASA Image and Video Library

    1959-08-01

    Big Joe Capsule Assembly Activities in 1959 at NASA Glenn Research Center (formerly NASA Lewis). Big Joe was an Atlas missile that successfully launched a boilerplate model of the Mercury capsule on September 9, 1959.

  11. Capsule injection system for a hydraulic capsule pipelining system

    DOEpatents

    Liu, Henry

    1982-01-01

    An injection system for injecting capsules into a hydraulic capsule pipelining system, the pipelining system comprising a pipeline adapted for flow of a carrier liquid therethrough, and capsules adapted to be transported through the pipeline by the carrier liquid flowing through the pipeline. The injection system comprises a reservoir of carrier liquid, the pipeline extending within the reservoir and extending downstream out of the reservoir, and a magazine in the reservoir for holding capsules in a series, one above another, for injection into the pipeline in the reservoir. The magazine has a lower end in communication with the pipeline in the reservoir for delivery of capsules from the magazine into the pipeline.

  12. A nanomechanical study of the effects of colistin on the Klebsiella pneumoniae AJ218 capsule.

    PubMed

    Mularski, Anna; Wilksch, Jonathan; Hanssen, Eric; Li, Jian; Tomita, Takehiro; Pidot, Sacha James; Stinear, Tim; Separovic, Frances; Strugnell, Dick

    2017-05-01

    Atomic force microscopy measurements of capsule thickness revealed that that the wild-type Klebsiella pneumoniae AJ218 capsular polysaccharides were rearranged by exposure to colistin. The increase in capsule thickness measured near minimum inhibitory/bactericidal concentration (MIC/MBC) is consistent with the idea that colistin displaces the divalent cations that cross-bridge adjacent lipopolysaccharide (LPS) molecules through the capsule network. Cryo-electron microscopy demonstrated that the measured capsule thickness at near MIC/MBC of 1.2 μM was inflated by the disrupted outer membrane, through which the capsule is excreted and LPS is bound. Since wild-type and capsule-deficient strains of K. pneumoniae AJ218 have equivalent MICs and MBCs, the presence of the capsule appeared to confer no protection against colistin in AJ218. A spontaneously arising colistin mutant showed a tenfold increase in resistance to colistin; genetic analysis identified a single amino acid substitution (Q95P) in the PmrB sensor kinase in this colistin-resistant K. pneumoniae AJ218. Modification of the lipid A component of the LPS could result in a reduction of the net-negative charge of the outer membrane, which could hinder binding of colistin to the outer membrane and displacement of the divalent cations that bridge adjacent LPS molecules throughout the capsular polysaccharide network. Retention of the cross-linking divalent cations may explain why measurements of capsule thickness did not change significantly in the colistin-resistant strain after colistin exposure. These results contrast with those for other K. pneumoniae strains that suggest that the capsule confers colistin resistance.

  13. Polysaccharide biological response modifiers.

    PubMed

    Leung, M Y K; Liu, C; Koon, J C M; Fung, K P

    2006-06-15

    Biological response modifiers (BRMs) are substances which augment immune response. BRMs can be cytokines which are produced endogenously in our body by immune cells or derivatives of bacteria, fungi, brown algae, Aloe vera and photosynthetic plants. Such exogeneous derivatives (exogeneous BRMs) can be nucleic acid (CpG), lipid (lipotechoic acid), protein or polysaccharide in nature. The receptors for these exogeneous BRMs are pattern recognition receptors. The binding of exogeneous BRMs to pattern recognition receptors triggers immune response. Exogenous BRMs have been reported to have anti-viral, anti-bacterial, anti-fungal, anti-parasitic, and anti-tumor activities. Among different exogeneous BRMs, polysaccharide BRMs have the widest occurrence in nature. Some polysaccharide BRMs have been tested for their therapeutic properties in human clinical trials. An overview of current understandings of polysaccharide BRMs is summarized in this review.

  14. Effects of Lipopolysaccharide Biosynthesis Mutations on K1 Polysaccharide Association with the Escherichia coli Cell Surface

    PubMed Central

    Jiménez, Natalia; Senchenkova, Sofya N.; Knirel, Yuriy A.; Pieretti, Giuseppina; Corsaro, Maria M.; Aquilini, Eleonora; Regué, Miguel; Merino, Susana

    2012-01-01

    The presence of cell-bound K1 capsule and K1 polysaccharide in culture supernatants was determined in a series of in-frame nonpolar core biosynthetic mutants from Escherichia coli KT1094 (K1, R1 core lipopolysaccharide [LPS] type) for which the major core oligosaccharide structures were determined. Cell-bound K1 capsule was absent from mutants devoid of phosphoryl modifications on l-glycero-d-manno-heptose residues (HepI and HepII) of the inner-core LPS and reduced in mutants devoid of phosphoryl modification on HepII or devoid of HepIII. In contrast, in all of the mutants, K1 polysaccharide was found in culture supernatants. These results were confirmed by using a mutant with a deletion spanning from the hldD to waaQ genes of the waa gene cluster to which individual genes were reintroduced. A nuclear magnetic resonance (NMR) analysis of core LPS from HepIII-deficient mutants showed an alteration in the pattern of phosphoryl modifications. A cell extract containing both K1 capsule polysaccharide and LPS obtained from an O-antigen-deficient mutant could be resolved into K1 polysaccharide and core LPS by column chromatography only when EDTA and deoxycholate (DOC) buffer were used. These results suggest that the K1 polysaccharide remains cell associated by ionically interacting with the phosphate-negative charges of the core LPS. PMID:22522903

  15. Uronic polysaccharide degrading enzymes.

    PubMed

    Garron, Marie-Line; Cygler, Miroslaw

    2014-10-01

    In the past several years progress has been made in the field of structure and function of polysaccharide lyases (PLs). The number of classified polysaccharide lyase families has increased to 23 and more detailed analysis has allowed the identification of more closely related subfamilies, leading to stronger correlation between each subfamily and a unique substrate. The number of as yet unclassified polysaccharide lyases has also increased and we expect that sequencing projects will allow many of these unclassified sequences to emerge as new families. The progress in structural analysis of PLs has led to having at least one representative structure for each of the families and for two unclassified enzymes. The newly determined structures have folds observed previously in other PL families and their catalytic mechanisms follow either metal-assisted or Tyr/His mechanisms characteristic for other PL enzymes. Comparison of PLs with glycoside hydrolases (GHs) shows several folds common to both classes but only for the β-helix fold is there strong indication of divergent evolution from a common ancestor. Analysis of bacterial genomes identified gene clusters containing multiple polysaccharide cleaving enzymes, the Polysaccharides Utilization Loci (PULs), and their gene complement suggests that they are organized to process completely a specific polysaccharide.

  16. MRI of intact plants.

    PubMed

    Van As, Henk; Scheenen, Tom; Vergeldt, Frank J

    2009-01-01

    Nuclear magnetic resonance imaging (MRI) is a non-destructive and non-invasive technique that can be used to acquire two- or even three-dimensional images of intact plants. The information within the images can be manipulated and used to study the dynamics of plant water relations and water transport in the stem, e.g., as a function of environmental (stress) conditions. Non-spatially resolved portable NMR is becoming available to study leaf water content and distribution of water in different (sub-cellular) compartments. These parameters directly relate to stomatal water conductance, CO(2) uptake, and photosynthesis. MRI applied on plants is not a straight forward extension of the methods discussed for (bio)medical MRI. This educational review explains the basic physical principles of plant MRI, with a focus on the spatial resolution, factors that determine the spatial resolution, and its unique information for applications in plant water relations that directly relate to plant photosynthetic activity. © Springer Science+Business Media B.V. 2009

  17. The physics of intact capture

    NASA Technical Reports Server (NTRS)

    Tsou, Peter; Griffiths, D. J.; Albee, A. L.

    1994-01-01

    The ability to capture projectiles intact at hypervelocities in underdense media open a new area of study in physics. Underdense material behaves markedly different than solid, liquid, or gas upon hypervelocity impact. This new phenomenon enables applications in science that would either not be possible or would be very costly by other means. This phenomenon has been fully demonstrated in the laboratory and validated in space. Even more interesting is the fact that this hypervelocity intact capture was accomplished passively. A better understanding of the physics of intact capture will lead to improvements in intact capture. A collection of physical observations of this phenomenon is presented here.

  18. The physics of intact capture

    NASA Technical Reports Server (NTRS)

    Tsou, Peter; Griffiths, D. J.; Albee, A. L.

    1994-01-01

    The ability to capture projectiles intact at hypervelocities in underdense media open a new area of study in physics. Underdense material behaves markedly different than solid, liquid, or gas upon hypervelocity impact. This new phenomenon enables applications in science that would either not be possible or would be very costly by other means. This phenomenon has been fully demonstrated in the laboratory and validated in space. Even more interesting is the fact that this hypervelocity intact capture was accomplished passively. A better understanding of the physics of intact capture will lead to improvements in intact capture. A collection of physical observations of this phenomenon is presented here.

  19. Comparative pharmacokinetics and pharmacodynamics of lansoprazole oral capsules and suspension in healthy subjects.

    PubMed

    Doan, T T; Wang, Q; Griffin, J S; Lukasik, N L; O'Dea, R F; Pan, W J

    2001-08-15

    The pharmacokinetics and pharmacodynamics of lansoprazole suspension and lansoprazole capsules were studied. Thirty-six healthy males and females were randomized in a single-dose, open-label, two-period crossover study. Lansoprazole 30 mg was administered via a nasogastric tube as simplified lansoprazole suspension (in 8.4% sodium bicarbonate) or orally as the intact capsule after a minimum 12-hour fast and 5 hours before lunch. Ambulatory 24-hour intragastric pH was monitored at baseline and on day 1 of each treatment period to assess lansoprazole's pharmacodynamics. Blood samples were collected before drug administration and at predetermined intervals up to 24 hours after each dose to assess lansoprazole's pharmacokinetics. Both formulations effectively raised the mean 24-hour intragastric pH (mean 24-hour pH of 3.75 with suspension and 3.52 with intact capsule) and maintained it above threshold values of 3 and 4 for more than 40% of the 24-hour postdose period. The suspension was associated with a significantly shorter mean time to the maximum observed concentration (tmax) compared with the intact capsule. The mean maximum observed plasma concentration (Cmax) of the suspension was significantly higher and the mean area under the concentration-time curve from time zero to infinity (AUC infinity) was significantly lower than those of the intact capsule (879 versus 810 ng/mL and 1825 versus 2229 ng.hr/mL). The 90% confidence intervals obtained by two one-sided tests for both Cmax and AUC infinity were contained within the 0.80 to 1.25 range, confirming the bioequivalence of the two regimens. Simplified lansoprazole suspension effectively controls intragastric pH, is bioequivalent to the intact capsule, and represents an effective therapeutic option for patients who have difficulty swallowing or are unable to swallow lansoprazole capsules.

  20. Space research with intact organisms

    NASA Technical Reports Server (NTRS)

    Phillips, Robert W.; Haddy, Francis J.

    1992-01-01

    Effects of space exposure on intact organisms are briefly reviewed, and examples of future experiments that might provide new information on the role of gravity in the evolution of life are suggested. It is noted that long term experiments with intact plant and animals for studying gravitational thresholds will provide important new insights.

  1. Sweat collection capsule

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Delaplaine, R. W. (Inventor)

    1980-01-01

    A sweat collection capsule permitting quantitative collection of sweat is described. The device consists of a frame held immobile on the skin, a closure secured to the frame and absorbent material located next to the skin in a cavity formed by the frame and the closure. The absorbent material may be removed from the device by removing the closure from the frame while the frame is held immobile on the skin.

  2. Capsule-train stability

    NASA Astrophysics Data System (ADS)

    Bryngelson, Spencer H.; Freund, Jonathan B.

    2016-07-01

    Elastic capsules flowing in small enough tubes, such as red blood cells in capillaries, are well known to line up into regular single-file trains. The stability of such trains in somewhat wider channels, where this organization is not observed, is studied in a two-dimensional model system that includes full coupling between the viscous flow and suspended capsules. A diverse set of linearly amplifying disturbances, both long-time asymptotic (modal) and transient (nonmodal) perturbations, is identified and analyzed. These have a range of amplification rates and their corresponding forms are wavelike, typically dominated by one of five principal perturbation classes: longitudinal and transverse translations, tilts, and symmetric and asymmetric shape distortions. Finite-amplitude transiently amplifying perturbations are shown to provide a mechanism that can bypass slower asymptotic modal linear growth and precipitate the onset of nonlinear effects. Direct numerical simulations are used to verify the linear analysis and track the subsequent transition of the regular capsule trains into an apparently chaotic flow.

  3. Lens capsule structure assessed with atomic force microscopy

    PubMed Central

    Sueiras, Vivian M.; Moy, Vincent T.

    2015-01-01

    Purpose To image the ultrastructure of the anterior lens capsule at the nanoscale level using atomic force microscopy (AFM). Methods Experiments were performed on anterior lens capsules maintained in their in situ location surrounding the lens from six human cadavers (donor age range: 44–88 years), four cynomolgus monkeys (Macaca fascicularis age range: 4.83–8.92 years), and seven pigs (<6 months). Hydration of all samples was maintained using Dulbecco’s Modified Eagle Medium (DMEM). Whole lenses were removed from the eye and placed anterior side up in agarose gel before gel hardening where only the posterior half of the lens was contained within the gel. After the gel hardened, the Petri dish was filled with DMEM until the point where the intact lens was fully submerged. AFM was used to image the anterior lens surface in contact mode. An integrated analysis program was used to calculate the interfibrillar spacing, fiber diameter, and surface roughness of the samples. Results The AFM images depict a highly ordered fibrous structure at the surface of the lens capsule in all three species. The interfibrillar spacing for the porcine, cynomolgus monkey, and human lens capsules was 0.68±0.25, 1.80±0.39, and 1.08±0.25 μm, respectively. In the primate, interfibrillar spacing significantly decreased linearly as a function of age. The fiber diameters ranged from 50 to 950 nm. Comparison of the root mean square (RMS) and average deviation demonstrate that the surface of the porcine lens capsule is the smoothest, and that the human and cynomolgus monkey capsules are significantly rougher. Conclusions AFM was successful in providing high-resolution images of the nanostructure of the lens capsule samples. Species-dependent differences were observed in the overall structure and surface roughness. PMID:25814829

  4. Adhesive capsulitis of the shoulder.

    PubMed

    Neviaser, Andrew S; Neviaser, Robert J

    2011-09-01

    Adhesive capsulitis is characterized by painful, gradual loss of active and passive shoulder motion resulting from fibrosis and contracture of the joint capsule. Other shoulder pathology can produce a similar clinical picture, however, and must be considered. Management is based on the underlying cause of pain and stiffness, and determination of the etiology is essential. Subtle clues in the history and physical examination can help differentiate adhesive capsulitis from other conditions that cause a stiff, painful shoulder. The natural history of adhesive capsulitis is a matter of controversy. Management of true capsular restriction of motion (ie, true adhesive capsulitis) begins with gentle, progressive stretching exercises. Most patients improve with nonsurgical treatment. Indications for surgery should be individualized. Failure to obtain symptomatic improvement and continued functional disability following ≥6 months of physical therapy is a general guideline for surgical intervention. Diligent postoperative therapy to maintain motion is required to minimize recurrence of adhesive capsulitis.

  5. Hohlraum Simulations for Symergy Capsules

    NASA Astrophysics Data System (ADS)

    Goldman, S. R.; Hoffman, N. M.; Kyrala, G. A.; Wilson, D. C.

    2006-10-01

    The use of a single capsule implosion within a hohlraum to provide information on both the asymmetry of the radiation drive impinging on the capsule and the total energy absorbed by it has led to the concept of experiments with ``symergy'' capsules. We present simulations for planned shots at Omega with hohlraum drive approximating the first 6 ns of the actual NIF ignition drive and surrogate capsules for the NIF ignition capsule. The hohlraum modeling can assess the effects of hohlraum gas fill, laser timing variations and beam pointings. In addition to its immediate design use, it should be useful in validating both the predictive capability for observed symergy capsule responses and the modeling of the initial stage of the NIF ignition process. N.M. Hoffman, D. C. Wilson, and G. A. Kyrala, 2006 High-Temperature Diagnostics Conference, May 2006, Williamsburg, VA USA, to appear in Rev Sci Inst. 77 (2006)

  6. Updated Campylobacter jejuni capsule PCR multiplex typing system and its application to clinical isolates from south and southeast Asia

    USDA-ARS?s Scientific Manuscript database

    Campylobacter jejuni produces a polysaccharide capsule that is the major determinant of the Penner serotyping scheme. This passive slide agglutination typing system was developed in the early 1980’s and was recognized for over two decades as gold standard for C. jejuni typing. A preliminary multiple...

  7. Medicinal mushrooms as a source of antitumor and immunomodulating polysaccharides.

    PubMed

    Wasser, S P

    2002-11-01

    polysaccharides requires an intact T-cell component; their activity is mediated through a thymus-dependent immune mechanism. Practical application is dependent not only on biological properties, but also on biotechnological availability. The present review analyzes the pecularities of polysaccharides derived from fruiting bodies and cultured mycelium (the two main methods of biotechnological production today) in selected examples of medicinal mushrooms.

  8. Effectiveness of intact capture media

    SciTech Connect

    Tsou, P.; Aubert, J.; Brownlee, D.; Hrubesh, L.; Williams, J.; Albee, A.

    1989-01-01

    The possibility of capturing cosmic dust at hypervelocity has been demonstrated in the laboratory and in the unintended Solar Max spacecraft. This technology will enable a comet coma sample return mission and be important for the earth orbital cosmic dust collection mission, i.e., the Space Station Cosmic Dust Collection Facility. Since the only controllable factor in an intact capture of cosmic dust is the capturing medium, characterizing the effectiveness and properties of available capture media would be very important in the development of the technique for capturing hypervelocity cosmic dust intact. We have evaluated various capture underdense media for the relative effectiveness for intact capture. 2 refs., 2 figs.

  9. Capsule endoscopy in celiac disease

    PubMed Central

    Spada, Cristiano; Riccioni, Maria Elena; Urgesi, Riccardo; Costamagna, Guido

    2008-01-01

    Video capsule endoscopy is an attractive and patient-friendly tool that provides high quality images of the small bowel. Obscure gastrointestinal bleeding is the primary and most evaluated indication to capsule endoscopy; however, indications are expanding and a small number of preliminary reports have been presented concerning the role of video capsule endoscopy in the diagnosis of celiac disease. The purpose of this review is to update the current knowledge and to hypothesize on future perspectives of the use of video capsule endoscopy in patients with celiac disease. PMID:18636659

  10. Capsule endoscopy in portal hypertension.

    PubMed

    Rondonotti, Emanuele; Villa, Federica; Dell' Era, Alessandra; Tontini, Gian Eugenio; de Franchis, Roberto

    2010-05-01

    Since the introduction of small bowel capsule endoscopy, and more recently of esophageal capsule endoscopy, these diagnostic tools have become available for the evaluation of the consequences of portal hypertension in the esophagus, stomach, and small intestine. The main advantage of the esophageal and the small bowel capsule is the relatively less invasiveness that could potentially increase patients' adherence to endoscopic screening/surveillance programs. When esophageal capsule endoscopy was compared with traditional gastroscopy, it showed good sensitivity and specificity in recognizing the presence and the size of esophageal varices. However, the results are not consistent among studies, and more data are needed.

  11. Posterior capsule opacification. Part 1: Experimental investigations.

    PubMed

    Nishi, O

    1999-01-01

    Posterior capsule opacification (PCO) is the most frequent complication associated with decreased vision after cataract surgery. Previous methods of preventing PCO have not proven to be practical, effective, and safe for routine clinical procedure, but some novel concepts and methods have recently been developed. This 2-part review looks at clinical and experimental investigations of PCO, focusing on developments since 1992. Clinical aspects will be presented in a later issue. This paper addresses (1) in vitro models for PCO research; (2) pathophysiology and molecular biology of lens epithelial cells (LECs); (3) prevention of PCO. Of special interest are methods of culturing human LECs obtained by capsulotomy during cataract surgery, including those obtained with an intact capsular bag, to provide an in vitro model for investigating the pathophysiology of LECs; the effect of a sharp bend in the lens capsule that induces contact inhibition of migrating LECs; more specific inhibition of migrating LECs using an immunotoxin, b-FGF-saporin, or EDTA and RGD-peptides.

  12. [Effects of microporous polysaccharide on foreign body reaction induced by subcutaneously imbedding expanded polytetrafluoroethylene in mice].

    PubMed

    Liu, Y H; Chen, L; Wu, Y P; Cao, W

    2016-10-20

    Objective: To observe the effects of early applying of microporous polysaccharide on foreign body reaction induced by subcutaneously imbedding expanded polytetrafluoroethylene (e-PTFE) in mice. Methods: Ten wide type adult C57BL/6J mice were collected and made a full-thickness skin incision on both sides of their back. The two incisions on the back of each mouse were divided into two groups according the random number table, with 10 incisions in each group. A tube-shaped e-PTFE was imbedded into each incision in microporous polysaccharide group, and then 0.03 g microporous polysaccharide was evenly sprayed in the cavity. Whereas, a tube-shaped e-PTFE was imbedded into each incision in control group without other treatment. The incisions in two groups were performed with conventional full-thickness suture. On post operation day (POD) 14, the e-PTFE surrounded with fibrous capsule in each incision of two groups was taken out, and then fibrous capsule tissue was harvested. The thickness of fibrous capsule was observed and measured with HE staining. Collagen fiber distribution in fibrous capsule tissue was observed with Masson staining to calculate the collagen fiber index. Neovascularization and macrophage infiltration in fibrous capsule tissue were observed respectively with immunohistochemical staining, and the numbers of new vessels and macrophages were counted. Data were processed with t test. Results: On POD 14, the thickness of fibrous capsule surrounding e-PTFE imbedded into the incision of microporous polysaccharide group was (127±19) μm, which was significantly thinner than that of control group [(250±35) μm, t=4.13, P<0.05]. On POD 14, the collagen fiber index of fibrous capsule tissue surrounding e-PTFE imbedded into the incision of microporous polysaccharide group was 0.500±0.003, which was significantly higher than that of control group (0.488±0.004, t=5.00, P<0.05). On POD 14, the number of new vessels in fibrous capsule tissue surrounding e

  13. Capsules from Pathogenic and Non-Pathogenic Cryptococcus spp. Manifest Significant Differences in Structure and Ability to Protect against Phagocytic Cells

    PubMed Central

    Araujo, Glauber de S.; Fonseca, Fernanda L.; Pontes, Bruno; Torres, Andre; Cordero, Radames J. B.; Zancopé-Oliveira, Rosely M.; Casadevall, Arturo; Viana, Nathan B.; Nimrichter, Leonardo; Rodrigues, Marcio L.; Garcia, Eloi S.; de Souza, Wanderley; Frases, Susana

    2012-01-01

    Capsule production is common among bacterial species, but relatively rare in eukaryotic microorganisms. Members of the fungal Cryptococcus genus are known to produce capsules, which are major determinants of virulence in the highly pathogenic species Cryptococcus neoformans and Cryptococcus gattii. Although the lack of virulence of many species of the Cryptococcus genus can be explained solely by the lack of mammalian thermotolerance, it is uncertain whether the capsules from these organisms are comparable to those of the pathogenic cryptococci. In this study, we compared the characteristic of the capsule from the non-pathogenic environmental yeast Cryptococcus liquefaciens with that of C. neoformans. Microscopic observations revealed that C. liquefaciens has a capsule visible in India ink preparations that was also efficiently labeled by three antibodies generated to specific C. neoformans capsular antigens. Capsular polysaccharides of C. liquefaciens were incorporated onto the cell surface of acapsular C. neoformans mutant cells. Polysaccharide composition determinations in combination with confocal microscopy revealed that C. liquefaciens capsule consisted of mannose, xylose, glucose, glucuronic acid, galactose and N-acetylglucosamine. Physical chemical analysis of the C. liquefaciens polysaccharides in comparison with C. neoformans samples revealed significant differences in viscosity, elastic properties and macromolecular structure parameters of polysaccharide solutions such as rigidity, effective diameter, zeta potential and molecular mass, which nevertheless appeared to be characteristics of linear polysaccharides that also comprise capsular polysaccharide of C. neoformans. The environmental yeast, however, showed enhanced susceptibility to the antimicrobial activity of the environmental phagocytes, suggesting that the C. liquefaciens capsular components are insufficient in protecting yeast cells against killing by amoeba. These results suggest that capsular

  14. The capsule's contribution to total hip construct stability--a finite element analysis.

    PubMed

    Elkins, Jacob M; Stroud, Nicholas J; Rudert, M James; Tochigi, Yuki; Pedersen, Douglas R; Ellis, Benjamin J; Callaghan, John J; Weiss, Jeffrey A; Brown, Thomas D

    2011-11-01

    Instability is a significant concern in total hip arthroplasty (THA), particularly when there is structural compromise of the capsule due to pre-existing pathology or due to necessities of surgical approach. An experimentally grounded fiber-direction-based finite element model of the hip capsule was developed, and was integrated with an established three-dimensional model of impingement/dislocation. Model validity was established by close similarity to results from a cadaveric experiment in a servohydraulic hip simulator. Parametric computational runs explored effects of graded levels of capsule thickness, of regional detachment from the capsule's femoral or acetabular insertions, of surgical incisions of capsule substance, and of capsule defect repairs. Depending strongly upon the specific site, localized capsule defects caused varying degrees of construct stability compromise, with several specific situations involving over 60% decrement in dislocation resistance. Construct stability was returned substantially toward intact-capsule levels following well-conceived repairs, although the suture sites involved were often at substantial risk of failure. These parametric model results underscore the importance of retaining or robustly repairing capsular structures in THA, in order to maximize overall construct stability. 

  15. Magnetism in metal-organic capsules

    SciTech Connect

    Atwood, Jerry L.; Brechin, Euan K; Dalgarno, Scott J.; Inglis, Ross; Jones, Leigh F.; Mossine, Andrew; Paterson, Martin J.; Power, Nicholas P.; Teat, Simon J.

    2010-01-07

    Nickel and cobalt seamed metal-organic capsules have been isolated and studied using structural, magnetic and computational approaches. Antiferromagnetic exchange in the Ni capsule results from coordination environments enforced by the capsule framework.

  16. Polysaccharide formulation for improvement of racemic vitamin E bioavailability.

    PubMed

    Zimmer, Łukasz; Czarnecki, Wiktor

    2007-01-01

    The relative bioavailability of polysaccharide--racemic vitamin E preparation in comparison with a commercial product was assessed in a kinetic study of plasma alpha-tocopherol in rabbits. Six male rabbits were used in a cross-over design. Alpha-Tocopherol levels were determined by the fluorometric method. A secondary peak in alpha-Tocopherol plasma concentration--time profiles was observed in connection with enterohepatic circulation of vitamin E. A simple one-compartment pharmacokinetic model was proposed to explain enterohepatic circulation of alpha-tocopherol in rabbits. On the basis of the results obtained, it is apparent that polysaccharide--vitamin E preparation achieved a higher rate and extent of absorption. The total AUC of experimental preparation was 1.78-fold greater than that of a commercial capsule preparation, suggesting an increase of bioavailability by 78%.

  17. Spacecraft Escape Capsule

    NASA Technical Reports Server (NTRS)

    Robertson, Edward A.; Charles, Dingell W.; Bufkin, Ann L.; Rodriggs, Liana M.; Peterson, Wayne; Cuthbert, Peter; Lee, David E.; Westhelle, Carlos

    2006-01-01

    A report discusses the Gumdrop capsule a conceptual spacecraft that would enable the crew to escape safely in the event of a major equipment failure at any time from launch through atmospheric re-entry. The scaleable Gumdrop capsule would comprise a command module (CM), a service module (SM), and a crew escape system (CES). The CM would contain a pressurized crew environment that would include avionic, life-support, thermal control, propulsive attitude control, and recovery systems. The SM would provide the primary propulsion and would also supply electrical power, life-support resources, and active thermal control to the CM. The CES would include a solid rocket motor, embedded within the SM, for pushing the CM away from the SM in the event of a critical thermal-protection-system failure or loss of control. The CM and SM would normally remain integrated with each other from launch through recovery, but could be separated using the CES, if necessary, to enable the safe recovery of the crew in the CM. The crew escape motor could be used, alternatively, as a redundant means of de-orbit propulsion for the CM in the event of a major system failure in the SM.

  18. Magneto-responsive alginate capsules

    NASA Astrophysics Data System (ADS)

    Degen, Patrick; Zwar, Elena; Schulz, Imke; Rehage, Heinz

    2015-05-01

    Upon incorporation of magnetic nanoparticles (mNPs) into gels, composite materials called ferrogels are obtained. These magneto-responsive systems have a wide range of potential applications including switches and sensors as well as drug delivery systems. In this article, we focus on the properties of calcium alginate capsules, which are widely used as carrier systems in medicine and technology. We studied the incorporation of different kinds of mNPs in matrix capsules and in the core and the shell of hollow particles. We found out that not all particle-alginate or particle-CaCl2 solution combinations were suitable for a successful capsule preparation on grounds of a destabilization of the nanoparticles or the polymer. For those systems allowing the preparation of switchable beads or capsules, we systematically studied the size and microscopic structure of the capsules, their magnetic behavior and mechanical resistance.

  19. Impulse-driven Micromechanism Capsule

    NASA Astrophysics Data System (ADS)

    Ito, Takahiro; Ishimori, Shohei; Hayashi, Teru

    We have developed a traveling small capsule, which has a smooth outer surface and is driven by inertia force and friction force. Measuring only 7 mm in diameter and 12 mm in length, it is sufficiently small to be placed in the human gullet or intestines. The capsule contains a small magnet and a coil, and an electric pulse drives the magnet to move the capsule. We performed an experimental investigation on making our capsule travel on a plastic material, which has similar elasticity characteristics to the living body. We also showed that it can travel on the surface of a pig's intestine. Our capsule may be useful for medical treatments such as inspection, drug delivery and operation.

  20. Comamonas testosteronan synthase, a bifunctional glycosyltransferase that produces a unique heparosan polysaccharide analog.

    PubMed

    Otto, Nigel J; Solakyildirim, Kemal; Linhardt, Robert J; DeAngelis, Paul L

    2011-10-01

    Glycosaminoglycans (GAGs) are linear hexosamine-containing polysaccharides. These polysaccharides are synthesized by some pathogenic bacteria to form an extracellular coating or capsule. This strategy forms the basis of molecular camouflage since vertebrates possess naturally occurring GAGs that are essential for life. A recent sequence database search identified a putative protein from the opportunistic pathogen Comamonas testosteroni that exhibits similarity with the Pasteurella multocida GAG synthase PmHS1, which is responsible for the synthesis of a heparosan polysaccharide capsule. Initial supportive evidence included glucuronic acid (GlcUA)-containing polysaccharides extracted from C. testosteroni KF-1. We describe here the cloning and analysis of a novel Comamonas GAG synthase, CtTS. The GAG produced by CtTS in vitro consists of the sugars d-GlcUA and N-acetyl-D-glucosamine, but is insensitive to digestion by GAG digesting enzymes, thus has distinct glycosidic linkages from vertebrate GAGs. The backbone structure of the polysaccharide product [-4-D-GlcUA-α1,4-D-GlcNAc-α1-](n) was confirmed by nuclear magnetic resonance. Therefore, this novel GAG, testosteronan, consists of the same sugars as the biomedically relevant GAGs heparosan (N-acetyl-heparosan) and hyaluronan but may have distinct properties useful for future medical applications.

  1. Comamonas testosteronan synthase, a bifunctional glycosyltransferase that produces a unique heparosan polysaccharide analog

    PubMed Central

    Otto, Nigel J; Solakyildirim, Kemal; Linhardt, Robert J; DeAngelis, Paul L

    2011-01-01

    Glycosaminoglycans (GAGs) are linear hexosamine-containing polysaccharides. These polysaccharides are synthesized by some pathogenic bacteria to form an extracellular coating or capsule. This strategy forms the basis of molecular camouflage since vertebrates possess naturally occurring GAGs that are essential for life. A recent sequence database search identified a putative protein from the opportunistic pathogen Comamonas testosteroni that exhibits similarity with the Pasteurella multocida GAG synthase PmHS1, which is responsible for the synthesis of a heparosan polysaccharide capsule. Initial supportive evidence included glucuronic acid (GlcUA)-containing polysaccharides extracted from C. testosteroni KF-1. We describe here the cloning and analysis of a novel Comamonas GAG synthase, CtTS. The GAG produced by CtTS in vitro consists of the sugars d-GlcUA and N-acetyl-d-glucosamine, but is insensitive to digestion by GAG digesting enzymes, thus has distinct glycosidic linkages from vertebrate GAGs. The backbone structure of the polysaccharide product [-4-d-GlcUA-α1,4-d-GlcNAc-α1-]n was confirmed by nuclear magnetic resonance. Therefore, this novel GAG, testosteronan, consists of the same sugars as the biomedically relevant GAGs heparosan (N-acetyl-heparosan) and hyaluronan but may have distinct properties useful for future medical applications. PMID:21610195

  2. Meningococcal Polysaccharide Vaccine Failure in a Patient with C7 Deficiency and a Decreased Anticapsular Antibody Response

    DTIC Science & Technology

    2012-05-01

    Antibodies directed against the polysaccharide capsule increase serum bactericidal activity in complement sufficient individuals and are good...membrane proreins24 and lipooligosaccharides2 5 enhance bactericidal activity against the infecting strain and provide varying degrees of cross...protection ro strains from other sero groups in complement sufficient individuals, bur they are less effective at mediating opsonophagocyrosis.23 As a

  3. Stability of esomeprazole capsule contents after in vitro suspension in common soft foods and beverages.

    PubMed

    Johnson, David A; Roach, Albert C; Carlsson, Anders S; Karlsson, Anders A S; Behr, Dan E

    2003-06-01

    To determine the in vitro stability of esomeprazole pellets from an opened capsule after suspension in various common soft foods and beverages. In vitro study. Pharmaceutical company research laboratory. Pellets from opened esomeprazole 20-mg capsules were suspended in 100 ml of tap water, milk (1.5% fat), orange juice, apple juice, yogurt, or cultured milk for 30 minutes, then added to 500 ml of hydrochloric acid to simulate gastric acid exposure. After a 2-hour incubation, the mixture was filtered through a sieve, and the collected pellets were dissolved in an alkaline solution. Esomeprazole concentrations were measured using reverse-phase liquid chromatography The stability of the esomeprazole pellets exceeded 98% in all beverages and soft foods except milk. Administration of the pellets from an opened esomeprazole capsule shortly after suspending them in tap water, yogurt, cultured milk, orange juice, or apple juice may be a practical alternative for patients who cannot swallow an intact capsule. Bioavailability studies comparing esomeprazole administered as an intact capsule to that of the pellets from an opened capsule suspended in these beverages or soft foods are recommended to confirm these findings.

  4. Intact capture of hypervelocity particles

    NASA Technical Reports Server (NTRS)

    Tsou, P.; Brownlee, D. E.; Albee, A. L.

    1986-01-01

    Knowledge of the phase, structure, and crystallography of cosmic particles, as well as their elemental and isotopic compositions, would be very valuable information toward understanding the nature of our solar system. This information can be obtained from the intact capture of large mineral grains of cosmic particles from hypervelocity impacts. Hypervelocity experiments of intact capture in underdense media have indicated realistic potential in this endeaver. The recovery of the thermal blankets and louvers from the Solar Max spacecraft have independently verified this potential in the unintended capture of cosmic materials from hypervelocity impacts. Passive underdense media will permit relatively simple and inexpensive missions to capture cosmic particles intact, either by going to a planetary body or by waiting for the particles to come to the Shuttle or the Space Station. Experiments to explore the potential of using various underdense media for an intact comet sample capture up to 6.7 km/s were performed at NASA Ames Research Center Vertical Gun Range. Explorative hypervelocity experiments up to 7.9 km/s were also made at the Ernst Mach Institute. These experiments have proven that capturing intact particles at hypervelocity impacts is definitely possible. Further research is being conducted to achieve higher capture ratios at even higher hypervelocities for even smaller projectiles.

  5. Intact capture of hypervelocity particles

    NASA Astrophysics Data System (ADS)

    Tsou, P.; Brownlee, D. E.; Albee, A. L.

    Knowledge of the phase, structure, and crystallography of cosmic particles, as well as their elemental and isotopic compositions, would be very valuable information toward understanding the nature of our solar system. This information can be obtained from the intact capture of large mineral grains of cosmic particles from hypervelocity impacts. Hypervelocity experiments of intact capture in underdense media have indicated realistic potential in this endeaver. The recovery of the thermal blankets and louvers from the Solar Max spacecraft have independently verified this potential in the unintended capture of cosmic materials from hypervelocity impacts. Passive underdense media will permit relatively simple and inexpensive missions to capture cosmic particles intact, either by going to a planetary body or by waiting for the particles to come to the Shuttle or the Space Station. Experiments to explore the potential of using various underdense media for an intact comet sample capture up to 6.7 km/s were performed at NASA Ames Research Center Vertical Gun Range. Explorative hypervelocity experiments up to 7.9 km/s were also made at the Ernst Mach Institute. These experiments have proven that capturing intact particles at hypervelocity impacts is definitely possible. Further research is being conducted to achieve higher capture ratios at even higher hypervelocities for even smaller projectiles.

  6. Intact capture of cosmic dust

    NASA Technical Reports Server (NTRS)

    Tsou, P.

    1991-01-01

    The focus of this development effort is to capture dust particles at hypervelocities intact and unmelted in order to preserve volatile organics. At the same time, the capture process must minimize any organic elemental or compound contamination to prevent any compromise of exobiological analyses. Inorganic silicate aerogel has been developed as a successful capture medium to satisfy both requirements of intact capture and minimal organic contamination. Up to 6 km/s, silicate projectiles from a few microns up to 100 microns have been captured intact without any melting and with minimal loss of mass. Carbon in silicate aerogel can be reduced to less than 1 part in 1000 and hydrogen 3 parts in 1000 when baked in air. Under controlled inert gas environments, additional hydrocarbon reduction can be achieved.

  7. Pbx proteins in Cryptococcus neoformans cell wall remodeling and capsule assembly.

    PubMed

    Kumar, Pardeep; Heiss, Christian; Santiago-Tirado, Felipe H; Black, Ian; Azadi, Parastoo; Doering, Tamara L

    2014-05-01

    The cryptococcal capsule is a critical virulence factor of an important pathogen, but little is known about how it is associated with the cell or released into the environment. Two mutants lacking PBX1 and PBX2 were found to shed reduced amounts of the capsule polysaccharide glucuronoxylomannan (GXM). Nuclear magnetic resonance, composition, and physical analyses showed that the shed material was of normal mass but was slightly enriched in xylose. In contrast to previous reports, this material contained no glucose. Notably, the capsule fibers of pbxΔ mutant cells grown under capsule-inducing conditions were present at a lower than usual density and were loosely attached to the cell wall. Mutant cell walls were also defective, as indicated by phenotypes including abnormal cell morphology, reduced mating filamentation, and altered cell integrity. All observed phenotypes were shared between the two mutants and exacerbated in a double mutant. Consistent with a role in surface glycan synthesis, the Pbx proteins localized to detergent-resistant membrane domains. These results, together with the sequence motifs in the Pbx proteins, suggest that Pbx1 and Pbx2 are redundant proteins that act in remodeling the cell wall to maintain normal cell morphology and precursor availability for other glycan synthetic processes. Their absence results in aberrant cell wall growth and metabolic imbalance, which together impact cell wall and capsule synthesis, cell morphology, and capsule association. The surface changes also lead to increased engulfment by host phagocytes, consistent with the lack of virulence of pbx mutants in animal models.

  8. MsaB activates capsule production at the transcription level in Staphylococcus aureus

    PubMed Central

    Batte, Justin L.; Samanta, Dhritiman

    2016-01-01

    Staphylococcus aureus produces several virulence factors that allow it to cause a variety of infections. One of the major virulence factors is the capsule, which contributes to the survival of the pathogen within the host as a way to escape phagocytosis. The production of the capsular polysaccharide is encoded in a 16 gene operon, which is regulated in response to several environmental stimuli including nutrient availability. For instance, the capsule is produced in the late- and post-exponential growth phases, but not in the early- or mid-exponential growth phase. Several regulators are involved in capsule production, but the regulation of the cap operon is still poorly understood. In this study, we show that MsaB activates the cap operon by binding directly to a 10 bp repeat in the promoter region. We show that despite the fact that MsaB is expressed throughout four growth phases, it only activates capsule production in the late- and post-exponential growth phases. Furthermore, we find that MsaB does not bind to its target site in the early and mid-exponential growth phases. This correlates with decreased nutrient availability and capsule production. These data suggest either that MsaB binding ability changes in response to nutrients or that other cap operon regulators interfere with the binding of MsaB to its target site. This study increases our understanding of the regulation of capsule production and the mechanism of action of MsaB. PMID:26781313

  9. Polysaccharides: Occurrence, Significance, and Properties

    NASA Astrophysics Data System (ADS)

    Bemiller, James N.

    Polysaccharides are properties present significance in all living organisms where they carry out one or more of their diverse functions. While there is no specific category or definition of a complex polysaccharide, most are structurally complex. Polysaccharides contain 1-5 different monosaccharide (sugar) units. The different sugar units may have different anomeric configurations and/or be joined by different glycosidic linkages. Polysaccharides may be linear or branched. Branches may be short saccharide units on a linear backbone or the molecule may have a branch-on-branch structure; in either case, the branches may be isolated or clustered. Polysaccharides may contain non-carbohydrate groups. Esters or cyclic acetal groups, when present, can be removed by appropriate treatments. All polysaccharides are polydisperse, i. e., are present in a range of molecular weights rather than having a single molecular weight. Most are polymolecular, i. e., differ in fine structure from molecule to molecule. So most polysaccharides can be said to be structurally complex. They may be attached to protein molecules or to other polysaccharide molecules. They are solvated by water. Most dissolve in aqueous systems, especially if they are alkaline. Polysaccharides can be depolymerized by acids and heat, specific enzymes, and high pH systems following oxidation. Their hydroxyl groups can be esterified (acylated), etherified (alkylated), and oxidized. Amino groups can be acylated (and deacylated). Carboxyl groups can be converted into esters, amides, and amines. Structural modification makes the molecules even more complex and polymolecular and, perhaps, polydisperse.

  10. Influence of capsule shell composition on the performance indicators of hypromellose capsule in comparison to hard gelatin capsules.

    PubMed

    Al-Tabakha, Moawia M; Arida, Adi Issam; Fahelelbom, Khairi M S; Sadek, Bassem; Saeed, Dima Ahmed; Abu Jarad, Rami A; Jawadi, Jeevani

    2015-01-01

    The purpose of this study was to assess the in vitro performances of "vegetable" capsules in comparison to hard gelatin capsules in terms of shell weight variation, reaction to different humidity conditions, resistance to stress in the absence of moisture, powder leakage, disintegration and dissolution. Two types of capsules made of HPMC produced with (Capsule 2) or without (Capsule 3) a gelling agent and hard gelatin capsules (Capsule 1) were assessed. Shell weight variability was relatively low for all tested capsules shells. Although Capsule 1 had the highest moisture content under different humidity conditions, all capsule types were unable to protect the encapsulated hygroscopic polyvinylpyrrolidone (PVP) powder from surrounding humidity. The initial disintegration for all Capsule 1 occurred within 3 min, but for other types of capsules within 6 min (n = 18). Dissolution of acetaminophen was better when the deionized water (DIW) temperature increased from 32 to 42 °C in case of Capsule 1, but the effect of temperature was not significant for the other types of capsules. Acetaminphen dissolution from Capsule 1 was the fastest (i.e. >90% in 10 min) and independent of the media pH or contents unlike Capsule 2 which was influenced by the pH and dissolution medium contents. It is feasible to use hypromellose capsules shells with or without gelling agent for new lines of pharmaceutical products, however, there is a window for capsule shells manufacturing companies to improve the dissolution of their hypromellose capsules to match the conventional gelatin capsule shells and eventually replace them.

  11. Species in the Cryptococcus gattii Complex Differ in Capsule and Cell Size following Growth under Capsule-Inducing Conditions.

    PubMed

    Fernandes, Kenya E; Dwyer, Christine; Campbell, Leona T; Carter, Dee A

    2016-01-01

    related to infection and disease is important for determining whether these different species have clinical relevance. This study examined variation in attributes that are important for infecting and surviving in the host, including tolerance to various stresses, yeast cell size, and the amount of polysaccharide capsule that covers the cell. The cell size and capsule size were significantly different and inversely correlated across the species. Thermotolerance was highest in C. deuterogattii (VGII), the only species known to cause outbreaks, while most strains of the species C. bacillisporus (VGIII) and C. tetragattii (VGIV) grew poorly at 37°C. These findings argue for increased acceptance of the new species and may be useful for informing diagnosis and prognosis in clinical infection.

  12. Species in the Cryptococcus gattii Complex Differ in Capsule and Cell Size following Growth under Capsule-Inducing Conditions

    PubMed Central

    Fernandes, Kenya E.; Dwyer, Christine; Campbell, Leona T.

    2016-01-01

    traits related to infection and disease is important for determining whether these different species have clinical relevance. This study examined variation in attributes that are important for infecting and surviving in the host, including tolerance to various stresses, yeast cell size, and the amount of polysaccharide capsule that covers the cell. The cell size and capsule size were significantly different and inversely correlated across the species. Thermotolerance was highest in C. deuterogattii (VGII), the only species known to cause outbreaks, while most strains of the species C. bacillisporus (VGIII) and C. tetragattii (VGIV) grew poorly at 37°C. These findings argue for increased acceptance of the new species and may be useful for informing diagnosis and prognosis in clinical infection. PMID:28066814

  13. Immunochemistry of the Group-Specific Polysaccharide of Nocardia brasiliensis

    PubMed Central

    Estrada-Parra, Sergio; Zamora, Abel; Bojalil, L. F.

    1965-01-01

    Estrada-Parra, Sergio (Escuela Nacional de Ciencias Biológicas, México, D.F., México), Abel Zamora, and L. F. Bojalil. Immunochemistry of the group-specific polysaccharide of Nocardia brasiliensis. J. Bacteriol. 90:571–574. 1965.—The group-specific polysaccharide of Nocardia brasiliensis was further purified, yielding an amorphous white material with the following characteristics: [α]D20 = + 48; nitrogen, 0.5%; phosphorus, 0.1%; and ash as sodium, 0.8%. The polymer is made of d-arabinose and d-galactose in a molar ratio of 3:1, and no other sugars were detected. Mild hydrolysis liberates mainly arabinose. The polysaccharide consumes 3.46 μmoles of periodate per mg of polymer in 15 days at 4 C (this value remains constant after 4 more days). Oxidation results in destruction of two of the arabinose, with the formation of two glycerols after borohydride reduction and hydrolysis. The polysaccharide oxidized by periodate and reduced under mild acid hydrolysis at 20 C yields glycerol and a polymer formed by galactose and arabinose (in a ratio of 1:1) which is resistant to a second oxidation. Therefore, the polysaccharide is probably formed by a main chain of glactose linked 1,3 and arabinose linked 1,2 or 1,3 or both, and nonreducing side chains of arabofuranose residues. The intact polysaccharide cross-reacts with sera from patients with active tuberculosis, and this, as well as the homologous reaction, is abolished by oxidation with periodate. PMID:16562050

  14. Orion Capsule Mockup is Dropped

    NASA Image and Video Library

    An Orion capsule mockup is dropped from a plane 25,000 feet above the Arizona desert to test its parachute design. Orion will return to Earth at speeds faster than previous human spacecraft, and wi...

  15. Immunochemical characterization of the "native" type III polysaccharide of group B Streptococcus

    PubMed Central

    1976-01-01

    The type III polysaccharide of -roup B Streptococcus has been isolated and purified by a method that employs washing of intact cells at neutral pH. That the polysaccharide prepared by this procedure is the "native" type III antigen is suggested by its molecular size in excess of 10(6) daltons, its degradation by acid and heat treatment to a fragment with immunologic characteristics of the classical HCl antigen, and its type-specific serologic activity. The type III polysaccharide in native form contains sialic acid, galactose, glucose, glucosamine, heptose, and mannose. It is acidic in nature, is resistant to neuramindiase degradation, contains no O-acetyl groups, and does not share antigenic determinants with capsular type K1 antigen of Escherichia coli or Group B polysaccharide antigen of Neiserria meningitidis. PMID:55450

  16. BENCAP, LLC: CAPSULE VELOCITY TEST

    SciTech Connect

    Meidinger, Brian

    2005-09-07

    Ben Cap, LLC, has a technology that utilizes bebtonite to plug wells. The bentonite is encapsulated in a cardboard capsule, droped down to the bottom of the well where it is allowed to hydrate, causing the bentonite to expand and plug the well. This method of plugging a well is accepted in some, but not all states. This technology can save a significant amount of money when compared to cementing methods currently used to plug and abandon wells. The test objective was to obtain the terminal velocity of the capsule delivery system as it drops through a column of water in a wellbore. Once the terminal velocity is known, the bentonite swelling action can be timed not to begin swelling until it reaches the bottom of the well bore. The results of the test showed that an average speed of 8.93 plus or minus 0.12 ft/sec was achieved by the capsule as it was falling through a column of water. Plotting the data revealed a very linear function with the capsules achieving terminal velocity shortly after being released. The interference of the capsule impacting the casing was not readily apparent in any of the runs, but a siginal sampling anomaly was present in one run. Because the anomaly was so brief and not present in any of the other runs, no solid conclusions could be drawn. Additional testing would be required to determine the effects of capsules impacting a fluid level that is not at surface.

  17. Contraindications for video capsule endoscopy

    PubMed Central

    Bandorski, Dirk; Kurniawan, Niehls; Baltes, Peter; Hoeltgen, Reinhard; Hecker, Matthias; Stunder, Dominik; Keuchel, Martin

    2016-01-01

    Video capsule endoscopy (VCE) has been applied in the last 15 years in an increasing field of applications. Although many contraindications have been put into perspective, some precautions still have to be considered. Known stenosis of the gastrointestinal tract is a clear contraindication for VCE unless surgery is already scheduled or at least has been considered as an optional treatment modality. In patients with a higher incidence of stenosis, as in an established diagnosis of Crohn’s disease, clinical signs of obstruction, prior radiation or surgical small bowel resection, a preceding test with the self-dissolving patency capsule can override this contraindication. Endoscopic placement of the capsule should be considered in patients with swallowing disorders to avoid aspiration. Esophageal or gastric motility disorders may require endoscopic capsule transport or application of prokinetics if the real-time viewer proofs delayed transit. In pregnant women, VCE should be restricted to urgent cases where diagnosis cannot be postponed after delivery, as data on safety are missing. There is theoretical and clinical evidence that patients with implanted cardiac devices such as a pacemaker, cardioverters or left heart assist devices, can safely undergo VCE in spite of still existing contraindication by manufacturers. Children from the age of 2 years have safely undergone VCE. Although video capsules are not proven safe with magnetic resonance imaging (MRI), first single cases of patients incidentally undergoing MRI with an incorporated capsule have been reported, showing susceptibility artifacts but no signs of clinical harm. PMID:28018097

  18. Deformability-based capsule sorting

    NASA Astrophysics Data System (ADS)

    Le Goff, Anne; Munier, Nadege; Maire, Pauline; Edwards-Levy, Florence; Salsac, Anne-Virginie

    2015-11-01

    Many microfluidic devices have been developed for cancer diagnosis applications, most of which relying on costly antibodies. Since some cancer cells display abnormal mechanical properties, new sorting tools based on mechanical sensing are of particular interest. We present a simple, passive pinched flow microfluidic system for capsule sorting. The device consists of a straight microchannel containing a cylindrical obstacle. Thanks to a flow-focusing module placed at the channel entrance, capsules arrive well-centered in the vicinity of the obstacle. Pure size-sorting can be achieved at low shear rate. When increasing the shear rate, capsules are deformed in the narrow space between the pillar and the wall. The softer the capsule, the more tightly it wraps around the obstacle. After the obstacle, streamlines diverge, allowing for the separation between soft capsules, that follow central streamlines, and stiff capsules, that drift away from the obstacle with a wider angle. This proves that we have developed a flexible multipurpose sorting microsystem based on a simple design.

  19. The structure of the O-specific polysaccharide of Salmonella arizonae O21 (Arizona 22) containing N-acetylneuraminic acid.

    PubMed

    Vinogradov, E V; Knirel, Y A; Shashkov, A S; Paramonov, N A; Kochetkov, N K; Stanislavsky, E S; Kholodkova, E V

    1994-06-02

    The O-specific polysaccharide of S. arizonae O21 was found to contain 2-acetamido-2-deoxy-D-glucose, 2-acetamidino-2,6-dideoxy-L-galactose, N-acetylneuraminic acid, and O-acetyl groups. On the basis of 1H and 13C NMR studies of the intact and O-deacetylated polysaccharide and oligosaccharide fragments obtained by solvolysis with anhydrous hydrogen fluoride, partial methanolysis and partial hydrolysis, it was concluded that the O-specific polysaccharide has the following structure: [formula: see text

  20. Pneumococcal Capsule Synthesis Locus cps as Evolutionary Hotspot with Potential to Generate Novel Serotypes by Recombination.

    PubMed

    Mostowy, Rafal J; Croucher, Nicholas J; De Maio, Nicola; Chewapreecha, Claire; Salter, Susannah J; Turner, Paul; Aanensen, David M; Bentley, Stephen D; Didelot, Xavier; Fraser, Christophe

    2017-10-01

    Diversity of the polysaccharide capsule in Streptococcus pneumoniae-main surface antigen and the target of the currently used pneumococcal vaccines-constitutes a major obstacle in eliminating pneumococcal disease. Such diversity is genetically encoded by almost 100 variants of the capsule biosynthesis locus, cps. However, the evolutionary dynamics of the capsule remains not fully understood. Here, using genetic data from 4,519 bacterial isolates, we found cps to be an evolutionary hotspot with elevated substitution and recombination rates. These rates were a consequence of relaxed purifying selection and positive, diversifying selection acting at this locus, supporting the hypothesis that the capsule has an increased potential to generate novel diversity compared with the rest of the genome. Diversifying selection was particularly evident in the region of wzd/wze genes, which are known to regulate capsule expression and hence the bacterium's ability to cause disease. Using a novel, capsule-centered approach, we analyzed the evolutionary history of 12 major serogroups. Such analysis revealed their complex diversification scenarios, which were principally driven by recombination with other serogroups and other streptococci. Patterns of recombinational exchanges between serogroups could not be explained by serotype frequency alone, thus pointing to nonrandom associations between co-colonizing serotypes. Finally, we discovered a previously unobserved mosaic serotype 39X, which was confirmed to carry a viable and structurally novel capsule. Adding to previous discoveries of other mosaic capsules in densely sampled collections, these results emphasize the strong adaptive potential of the bacterium by its ability to generate novel antigenic diversity by recombination. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  1. Iodine-Catalyzed Polysaccharide Esterification

    USDA-ARS?s Scientific Manuscript database

    A review is provided of the recent reports to use iodine-catalyzed esterification reaction to produce esters from polysaccharides. The process entails reaction of the polysaccharide with an acid anhydride in the presence of a catalytic level of iodine, and in the absence of additional solvents. T...

  2. Monitoring Intact Viruses Using Aptamers.

    PubMed

    Kumar, Penmetcha K R

    2016-08-04

    Viral diagnosis and surveillance are necessary steps in containing the spread of viral diseases, and they help in the deployment of appropriate therapeutic interventions. In the past, the commonly employed viral detection methods were either cell-culture or molecule-level assays. Most of these assays are laborious and expensive, require special facilities, and provide a slow diagnosis. To circumvent these limitations, biosensor-based approaches are becoming attractive, especially after the successful commercialization of glucose and other biosensors. In the present article, I have reviewed the current progress using the biosensor approach for detecting intact viruses. At the time of writing this review, three types of bioreceptor surfaces (antibody-, glycan-, and aptamer-based) have been explored on different sensing platforms for detecting intact viruses. Among these bioreceptors, aptamer-based sensors have been increasingly explored for detecting intact viruses using surface plasmon resonance (SPR) and other platforms. Special emphasis is placed on the aptamer-based SPR platform in the present review.

  3. Monitoring Intact Viruses Using Aptamers

    PubMed Central

    Kumar, Penmetcha K. R.

    2016-01-01

    Viral diagnosis and surveillance are necessary steps in containing the spread of viral diseases, and they help in the deployment of appropriate therapeutic interventions. In the past, the commonly employed viral detection methods were either cell-culture or molecule-level assays. Most of these assays are laborious and expensive, require special facilities, and provide a slow diagnosis. To circumvent these limitations, biosensor-based approaches are becoming attractive, especially after the successful commercialization of glucose and other biosensors. In the present article, I have reviewed the current progress using the biosensor approach for detecting intact viruses. At the time of writing this review, three types of bioreceptor surfaces (antibody-, glycan-, and aptamer-based) have been explored on different sensing platforms for detecting intact viruses. Among these bioreceptors, aptamer-based sensors have been increasingly explored for detecting intact viruses using surface plasmon resonance (SPR) and other platforms. Special emphasis is placed on the aptamer-based SPR platform in the present review. PMID:27527230

  4. Polysaccharides of the red algae.

    PubMed

    Usov, Anatolii I

    2011-01-01

    Red algae (Rhodophyta) are known as the source of unique sulfated galactans, such as agar, agarose, and carrageenans. The wide practical uses of these polysaccharides are based on their ability to form strong gels in aqueous solutions. Gelling polysaccharides usually have molecules built up of repeating disaccharide units with a regular distribution of sulfate groups, but most of the red algal species contain more complex galactans devoid of gelling ability because of various deviations from the regular structure. Moreover, several red algae may contain sulfated mannans or neutral xylans instead of sulfated galactans as the main structural polysaccharides. This chapter is devoted to a description of the structural diversity of polysaccharides found in the red algae, with special emphasis on the methods of structural analysis of sulfated galactans. In addition to the structural information, some data on the possible use of red algal polysaccharides as biologically active polymers or as taxonomic markers are briefly discussed.

  5. Relative bioavailability of tizanidine hydrochloride capsule formulation compared with capsule contents administered in applesauce: a single-dose, open-label, randomized, two-way, crossover study in fasted healthy adult subjects.

    PubMed

    Henney, Herbert R; Fitzpatrick, Anthony; Stewart, Johnston; Runyan, Jacob D

    2008-12-01

    The alpha2-adrenergic agonist tizanidine has been reported to have a narrow therapeutic index. A multiparticulate capsule formulation of tizanidine has been developed in an attempt to improve patient tolerability. This study assessed bioequivalence between a single, intact, 6-mg capsule of tizanidine and the capsule contents sprinkled in applesauce in fasted healthy subjects. Healthy male and female subjects aged 18 to 45 years completed 2 treatment periods: one with a tizanidine 6-mg capsule administered intact and the other with capsule contents sprinkled in applesauce. The 2 treatment periods had a 6-day washout period between administrations. Plasma tizanidine concentrations were determined for blood samples collected over 24 hours after administration. All treatment-emergent adverse events were recorded and graded by intensity and relationship to the study drug (not, improbable, possible, probable, definite) by the attending physician based on his or her clinical impression. A total of 19 men and 9 women (mean age, 26 years) completed the trial. Geometric mean natural logarithm-transformed AUC values (AUC(0-infinity) [AUC to infinity] and AUC(0-t) [AUC to the last measurable time point]) and C(max) ratios were significantly (P intact capsule reporting 18 events and 11 subjects (39%) with the sprinkled contents reporting 13 events. No serious adverse events or deaths were reported, and no subjects were discontinued due to adverse events. The contents of the tizanidine capsule sprinkled in applesauce were not bioequivalent to the intact 6-mg capsule in these fasted healthy

  6. Cations modulate polysaccharide structure to determine FGF-FGFR signaling: a comparison of signaling and inhibitory polysaccharide interactions with FGF-1 in solution.

    PubMed

    Guimond, Scott E; Rudd, Timothy R; Skidmore, Mark A; Ori, Alessandro; Gaudesi, Davide; Cosentino, Cesare; Guerrini, Marco; Edge, Ruth; Collison, David; McInnes, Eric; Torri, Giangiacomo; Turnbull, Jeremy E; Fernig, David G; Yates, Edwin A

    2009-06-09

    For heparan sulfate (HS) to bind and regulate the activity of proteins, the polysaccharide must present an appropriate sequence and adopt a suitable conformation. The conformations of heparin derivatives, as models of HS, are altered via a change in the associated cations, and this can drastically modify their FGF signaling activities. Here, we report that changing the cations associated with an N-acetyl-enriched heparin polysaccharide, from sodium to copper(II), converted it from supporting signaling through the fibroblast growth factor receptor (FGF-1-FGFR1c) tyrosine kinase signaling system to being inhibitory in a cell-based BaF3 assay. Nuclear magnetic resonance and synchrotron radiation circular dichroism (SRCD) spectroscopy demonstrated that the polysaccharide conformation differed in the presence of sodium or copper(II) cations. Electron paramagnetic resonance confirmed the environment of the copper(II) ion on the N-acetyl-enriched polysaccharide was distinct from that previously observed with intact heparin, which supported signaling. Secondary structures in solution complexes of polysaccharides with FGF-1 (which either supported signaling through FGFR1c or were inhibitory) were determined by SRCD. This allowed direct comparison of the two FGF-1-polysaccharide complexes in solution, containing identical molecular components and differing only in their cation content. Subtle structural differences were revealed, including a reduction in the level of disordered structure in the inhibitory complex.

  7. Vaccination with peptide mimotopes produces antibodies recognizing bacterial capsular polysaccharides.

    PubMed

    Wu, Yang; Zhang, Qibo; Sales, Debra; Bianco, Albert Edward; Craig, Alister

    2010-09-07

    A phage display peptide library was screened using a panel of antibodies to the capsular polysaccharides of Streptococcus agalactiae and Neisseria meningitidis. Mimotopes NPDHPRVPTFMA (2-8), LIPFHKHPHHRG (3-2) and EQEIFTNITDRV (G3) showing the highest binding capacity and strongest ELISA reaction were selected for immunization experiments. These mimotopes were either synthesised as oligodeoxynucleotides for DNA immunization or MAP (multiple antigen peptide) for peptide immunization. Mimotope-DNA vaccination, particularly for G3, induced antibodies recognizing a number of target bacteria. This response was seen after the second boost injection and was significantly enhanced by the 3rd boost injection with a Th1-associated profile, which was dominated by IgG2a, followed by IgG1. Mimotope-MAP immunization also produced strong humoral immune responses to the bacteria. Antibodies from G3 DNA immunization reacted with the surface molecules of S. agalactiae, N. meningitidis and Escherichia coli K5 shown by indirect immunofluorescence staining, indicating a possible localization to the bacterial capsule. Antibodies produced both from DNA/MAP immunization reacted with purified bacterial capsular polysaccharides by ELISA and were of high avidity. We have further characterized peptide G3 by a 'tiling path' study to examine the effect of changing individual residues in the peptide in raising antibodies, which showed that the EIFTN motif in G3 was important in generating antibodies to several capsulated bacteria. We conclude that mimotope immunization with DNA or MAP potentially induces strong antibody responses against encapsulated bacteria. It is suggested that the antibody targets are polysaccharides, and these antibodies may cross react at least among closely related species of bacteria.

  8. Polysaccharides from Extremophilic Microorganisms

    NASA Astrophysics Data System (ADS)

    Nicolaus, B.; Moriello, V. Schiano; Lama, L.; Poli, A.; Gambacorta, A.

    2004-02-01

    Several marine thermophilic strains were analyzed for exopolysaccharide production. The screening process revealed that a significant number of thermophilic microorganisms were able to produce biopolymers, and some of them also revealed interesting chemical compositions. We have identified four new polysaccharides from thermophilic marine bacteria, with complex primary structures and with different repetitive units: a galacto-mannane type from strain number 4004 and mannane type for the other strains. The thermophilic Bacillus thermantarcticus produces two exocellular polysaccharides (EPS 1, EPS 2) that give the colonies a typical mucous character. The exopolysaccharide fraction was produced with all substrates assayed, although a higher yield 400 mg liter-1 was obtained with mannose as carbon and energy source. NMR spectra confirmed that EPS 1 was a heteropolysaccharide of which the repeating unit was constituted by four different α-D-mannoses and three different β-D-glucoses. It seems to be close to some xantan polymers. EPS 2 was a mannan. Four different α-D-mannoses were found as the repeating unit. Production and chemical studies of biopolymers produced by halophilic archaea, Haloarcula species were also reported.

  9. Why were polysaccharides necessary?

    PubMed

    Tolstoguzov, Vladimir

    2004-12-01

    The main idea of this paper is that the primordial soup may be modelled by food systems whose structure-property relationship is based on non-specific interactions between denatured biopolymers. According to the proposed hypothesis, polysaccharides were the first biopolymers that decreased concentration of salts in the primordial soup, 'compatibilised' and drove the joint evolution of proto-biopolymers. Synthesis of macromolecules within the polysaccharide-rich medium could have resulted in phase separation of the primordial soup and concentration of the polypeptides and nucleic acids in the dispersed phase particles. The concentration of proto-biopolymer mixtures favoured their cross-linking in hybrid supermacromolecules of conjugates. The cross-linking of proto-biopolymers could occur by hydrophobic, electrostatic interactions, H-bonds due to freezing aqueous mixed biopolymer dispersions and/or by covalent bonds due to the Maillard reaction. Cross-linking could have increased the local concentration of chemically different proto-biopolymers, fixed their relative positions and made their interactions reproducible. Attractive-repulsive interactions between cross-linked proto-biopolymer chains could develop pairing of the monomer units, improved chemical stability (against hydrolysis) and led to their mutual catalytic activity and coding. Conjugates could probably evolve to the first self-reproduced entities and then to specialized cellular organelles. Phase separation of the primordial soup with concentration of conjugates in the dispersed particles has probably resulted in proto-cells.

  10. Why Were Polysaccharides Necessary?

    NASA Astrophysics Data System (ADS)

    Tolstoguzov, Vladimir

    2004-12-01

    The main idea of this paper is that the primordial soup may be modelled by food systems whose structure-property relationship is based on non-specific interactions between denatured biopolymers. According to the proposed hypothesis, polysaccharides were the first biopolymers that decreased concentration of salts in the primordial soup, `compatibilised' and drove the joint evolution of proto-biopolymers. Synthesis of macromolecules within the polysaccharide-rich medium could have resulted in phase separation of the primordial soup and concentration of the polypeptides and nucleic acids in the dispersed phase particles. The concentration of proto-biopolymer mixtures favoured their cross-linking in hybrid supermacromolecules of conjugates. The cross-linking of proto-biopolymers could occur by hydrophobic, electrostatic interactions, H-bonds due to freezing aqueous mixed biopolymer dispersions and/or by covalent bonds due to the Maillard reaction. Cross-linking could have increased the local concentration of chemically different proto-biopolymers, fixed their relative positions and made their interactions reproducible. Attractive-repulsive interactions between cross-linked proto-biopolymer chains could develop pairing of the monomer units, improved chemical stability (against hydrolysis) and led to their mutual catalytic activity and coding. Conjugates could probably evolve to the first self-reproduced entities and then to specialized cellular organelles. Phase separation of the primordial soup with concentration of conjugates in the dispersed particles has probably resulted in proto-cells.

  11. Polysaccharides and bacterial plugging

    SciTech Connect

    Fogler, H.S.

    1991-11-01

    Before any successful application of Microbial Enhanced Oil Recovery process can be realized, an understanding of the cells' transport and retentive mechanisms in porous media is needed. Cell transport differs from particle transport in their ability to produce polysaccharides, which are used by cells to adhere to surfaces. Cell injection experiments have been conducted using Leuconostoc cells to illustrate the importance of cellular polysaccharide production as a transport mechanism that hinders cell movement and plugs porous media. Kinetic studies of the Leuconostoc cells, carried out to further understand the plugging rates of porous media, have shown that the cells' growth rates are approximately equal when provided with monosaccharide (glucose and fructose) or sucrose. The only difference in cell metabolism is the production of dextran when sucrose is supplied as a carbon source. Experimentally it has also been shown that the cells' growth rate is weakly dependent upon the sucrose concentration in the media, and strongly dependent upon the concentration of yeast extract. The synthesis of cellular dextran has been found to lag behind cell generation, thus indicating that the cells need to reach maturity before they are capable of expressing the detransucrase enzyme and synthesizing insoluble dextran. Dextran yields were found to be dependent upon the sucrose concentration in the media. 10 refs., 9 figs., 9 tabs.

  12. Summary Report for Capsule Dry Storage Project

    SciTech Connect

    JOSEPHSON, W S

    2003-09-04

    There are 1.936 cesium (Cs) and strontium (Sr) capsules stored in pools at the Waste Encapsulation and Storage Facility (WESF). These capsules will be moved to dry storage on the Hanford Site as an interim measure to reduce risk. The Cs/Sr Capsule Dry Storage Project (CDSP) is conducted under the assumption the capsules will eventually be moved to the repository at Yucca Mountain, and the design criteria include requirements that will facilitate acceptance at the repository. The storage system must also permit retrieval of capsules in the event vitrification of the capsule contents is pursued. A cut away drawing of a typical cesium chloride (CsCI) capsule and the capsule property and geometry information are provided in Figure 1.1. Strontium fluoride (SrF{sub 2}) capsules are similar in design to CsCl capsules. Further details of capsule design, current state, and reference information are given later in this report and its references. Capsule production and life history is covered in WMP-16938, Capsule Characterization Report for Capsule Dry Storage Project, and is briefly summarized in Section 5.2 of this report.

  13. Evidence for a LOS and a capsular polysaccharide in Capnocytophaga canimorsus

    PubMed Central

    Renzi, Francesco; Ittig, Simon J.; Sadovskaya, Irina; Hess, Estelle; Lauber, Frederic; Dol, Melanie; Shin, Hwain; Mally, Manuela; Fiechter, Chantal; Sauder, Ursula; Chami, Mohamed; Cornelis, Guy R.

    2016-01-01

    Capnocytophaga canimorsus is a dog’s and cat’s oral commensal which can cause fatal human infections upon bites or scratches. Infections mainly start with flu-like symptoms but can rapidly evolve in fatal septicaemia with a mortality as high as 40%. Here we present the discovery of a polysaccharide capsule (CPS) at the surface of C. canimorsus 5 (Cc5), a strain isolated from a fulminant septicaemia. We provide genetic and chemical data showing that this capsule is related to the lipooligosaccharide (LOS) and probably composed of the same polysaccharide units. A CPS was also found in nine out of nine other strains of C. canimorsus. In addition, the genomes of three of these strains, sequenced previously, contain genes similar to those encoding CPS biosynthesis in Cc5. Thus, the presence of a CPS is likely to be a common property of C. canimorsus. The CPS and not the LOS confers protection against the bactericidal effect of human serum and phagocytosis by macrophages. An antiserum raised against the capsule increased the killing of C. canimorsus by human serum thus showing that anti-capsule antibodies have a protective role. These findings provide a new major element in the understanding of the pathogenesis of C. canimorsus. PMID:27974829

  14. The molecular basis of polysaccharide cleavage by lytic polysaccharide monooxygenases

    PubMed Central

    Frandsen, Kristian E. H.; Simmons, Thomas J.; Dupree, Paul; Poulsen, Jens-Christian N.; Hemsworth, Glyn R.; Ciano, Luisa; Johnston, Esther M.; Tovborg, Morten; Johansen, Katja S.; von Freiesleben, Pernille; Marmuse, Laurence; Fort, Sébastien; Cottaz, Sylvain; Driguez, Hugues; Henrissat, Bernard; Lenfant, Nicolas; Tuna, Floriana; Baldansuren, Amgalanbaatar; Davies, Gideon J.; Leggio, Leila Lo; Walton, Paul H.

    2016-01-01

    Lytic polysaccharide monooxygenases (LPMOs) are copper-containing enzymes which oxidatively break down recalcitrant polysaccharides such as cellulose and chitin. Since their discovery LPMOs have become integral factors in the industrial utilization of biomass, especially in the sustainable generation of cellulosic bioethanol. We report here the first structural determination of an LPMO–oligosaccharide complex, yielding detailed insights into the mechanism of action of these enzymes. Using a combination of structure and electron paramagnetic resonance spectroscopy, we reveal the means by which LPMOs interact with saccharide substrates. We further uncover electronic and structural features of the enzyme active site, showing how LPMOs orchestrate the reaction of oxygen with polysaccharide chains. PMID:26928935

  15. Streptococcus pneumoniae phosphotyrosine phosphatase CpsB and alterations in capsule production resulting from changes in oxygen availability.

    PubMed

    Geno, K Aaron; Hauser, Jocelyn R; Gupta, Kanupriya; Yother, Janet

    2014-06-01

    Streptococcus pneumoniae produces a protective capsular polysaccharide whose production must be modulated for bacterial survival within various host niches. Capsule production is affected in part by a phosphoregulatory system comprised of CpsB, CpsC, and CpsD. Here, we found that growth of serotype 2 strain D39 under conditions of increased oxygen availability resulted in decreased capsule levels concurrent with an ∼5-fold increase in Cps2B-mediated phosphatase activity. The change in Cps2B phosphatase activity did not result from alterations in the levels of either the cps2B transcript or the Cps2B protein. Recombinant Cps2B expressed in Escherichia coli similarly exhibited increased phosphatase activity under conditions of high-oxygen growth. S. pneumoniae D39 derivatives with defined deletion or point mutations in cps2B demonstrated reduced phosphatase activity with corresponding increases in levels of Cps2D tyrosine phosphorylation. There was, however, no correlation between these phenotypes and the level of capsule production. During growth under reduced-oxygen conditions, the Cps2B protein was essential for parental levels of capsule, but phosphatase activity alone could be eliminated without an effect on capsule. Under increased-oxygen conditions, deletion of cps2B did not affect capsule levels. These results indicate that neither Cps2B phosphatase activity nor Cps2D phosphorylation levels per se are determinants of capsule levels, whereas the Cps2B protein is important for capsule production during growth under conditions of reduced but not enhanced oxygen availability. Roles for factors outside the capsule locus, possible interactions between capsule regulatory proteins, and links to other cellular processes are also suggested by the results described in this study.

  16. Streptococcus pneumoniae Phosphotyrosine Phosphatase CpsB and Alterations in Capsule Production Resulting from Changes in Oxygen Availability

    PubMed Central

    Geno, K. Aaron; Hauser, Jocelyn R.; Gupta, Kanupriya

    2014-01-01

    Streptococcus pneumoniae produces a protective capsular polysaccharide whose production must be modulated for bacterial survival within various host niches. Capsule production is affected in part by a phosphoregulatory system comprised of CpsB, CpsC, and CpsD. Here, we found that growth of serotype 2 strain D39 under conditions of increased oxygen availability resulted in decreased capsule levels concurrent with an ∼5-fold increase in Cps2B-mediated phosphatase activity. The change in Cps2B phosphatase activity did not result from alterations in the levels of either the cps2B transcript or the Cps2B protein. Recombinant Cps2B expressed in Escherichia coli similarly exhibited increased phosphatase activity under conditions of high-oxygen growth. S. pneumoniae D39 derivatives with defined deletion or point mutations in cps2B demonstrated reduced phosphatase activity with corresponding increases in levels of Cps2D tyrosine phosphorylation. There was, however, no correlation between these phenotypes and the level of capsule production. During growth under reduced-oxygen conditions, the Cps2B protein was essential for parental levels of capsule, but phosphatase activity alone could be eliminated without an effect on capsule. Under increased-oxygen conditions, deletion of cps2B did not affect capsule levels. These results indicate that neither Cps2B phosphatase activity nor Cps2D phosphorylation levels per se are determinants of capsule levels, whereas the Cps2B protein is important for capsule production during growth under conditions of reduced but not enhanced oxygen availability. Roles for factors outside the capsule locus, possible interactions between capsule regulatory proteins, and links to other cellular processes are also suggested by the results described in this study. PMID:24659769

  17. Overproduction of Type 8 Capsular Polysaccharide Augments Staphylococcus aureus Virulence

    PubMed Central

    Luong, Thanh T.; Lee, Chia Y.

    2002-01-01

    Type 8 capsular polysaccharide (CP8) is the most prevalent capsule type in clinical isolates of Staphylococcus aureus. However, its role in virulence has not been clearly defined. CP8 strains such as strain Becker produce a small amount of capsule on their surface in vitro. In contrast, CP1 strains such as strain M produce a large amount of capsule, which has been shown to be an important antiphagocytic virulence factor. The cap8 and cap1 operons, required for the synthesis of CP8 and CP1, respectively, have been cloned and sequenced. To test whether CP8 contributes to the pathogenesis of S. aureus, we replaced the weak native promoter of the cap8 operon in strain Becker with the strong constitutive promoter of the cap1 operon of strain M. The resultant strain, CYL770, synthesized cap8-specific mRNA at a level about sevenfold higher than that in the parent strain. Remarkably, the CYL770 strain produced about 80-fold more CP8. In a mouse infection model of bacteremia, the CP8-overproducing strain persisted longer in the bloodstream, the liver, and the spleen in mice than the parent strain. In addition, strain CYL770 was more resistant to ospsonophagocytosis in vitro by human polymorphonuclear leukocytes. These results indicate that CP8 is an antiphagocytic virulence factor of S. aureus. PMID:12065477

  18. Equilibrium ignition for ICF capsules

    SciTech Connect

    Lackner, K.S.; Colgate, S.A.; Johnson, N.L.; Kirkpatrick, R.C.; Menikoff, R.; Petschek, A.G.

    1993-12-31

    There are two fundamentally different approaches to igniting DT fuel in an ICF capsule which can be described as equilibrium and hot spot ignition. In both cases, a capsule which can be thought of as a pusher containing the DT fuel is imploded until the fuel reaches ignition conditions. In comparing high-gain ICF targets using cryogenic DT for a pusher with equilibrium ignition targets using high-Z pushers which contain the radiation. The authors point to the intrinsic advantages of the latter. Equilibrium or volume ignition sacrifices high gain for lower losses, lower ignition temperature, lower implosion velocity and lower sensitivity of the more robust capsule to small fluctuations and asymmetries in the drive system. The reduction in gain is about a factor of 2.5, which is small enough to make the more robust equilibrium ignition an attractive alternative.

  19. [Effect of cordyceps polysaccharide on lipid peroxidation of rats with dimethylnitrosamine-induced liver fibrosis].

    PubMed

    Peng, Jing-Hua; Li, Xue-Mei; Hu, Yi-Yang; Feng, Qin

    2013-02-01

    To observe the pharmacological effect of Cordyceps polysaccharide on dimethylnitrosamine (DMN)-induced liver fibrosis in rats. DMN rat liver fibrosis model was established and divided into the normal group (N, n = 6), the model group (M, n = 11), the Cordyceps polysaccharide group (C, n = 8) and the colchicine group (Q, n = 9). During the modeling for four weeks, Cordyceps polysaccharide (60 mg x kg(-1)) and colchicine (0.1 mg x kg(-1)) were orally administered for three weeks, while the model and normal groups were given disinfected water of the same amount. serum ALT, AST, GGT and Alb, TBil content; content of hydroxyproline (Hyp) in liver tissues; liver pathology and collagen staining; SOD activity and MDA, GSH, GSH-Px in liver tissues; protein expression of proliferating cell nuclear antigen (PCNA) in liver tissues. Serum ALT, AST, GGT, TBil significantly increased, and A1b decreased significantly in the model group. Hepatic Hyp significantly increased in the model group, whereas the index remarkably decreased in the Cordyceps polysaccharide group and the colchicine group. HE staining: the structure of normal hepatic lobules was damaged, with hepatocytes tumefaction and proliferation of connective tissues in portal tracts in the model group, while the Cordyceps polysaccharide group and the colchicine group recorded notable reduction in above pathological changes. Collagen staining: the model group showed hepatic lobule fibrous septum and many intact pseudolobules; while the Cordyceps polysaccharide group and the colchicine group witnessed decrease in collagen deposition. The model group showed significant decrease in SOD, GSH-Px and GSH and increase in MDA, whereas the Cordyceps polysaccharide group and the colchicine group recorded notable growth in GSH and GSH-Px. The model group showed significant decrease in protein expression of PCNA in liver tissues, while the Cordyceps polysaccharide group and the colchicine group showed significant reduction. Cordyceps

  20. Triggered Release from Polymer Capsules

    SciTech Connect

    Esser-Kahn, Aaron P.; Odom, Susan A.; Sottos, Nancy R.; White, Scott R.; Moore, Jeffrey S.

    2011-07-06

    Stimuli-responsive capsules are of interest in drug delivery, fragrance release, food preservation, and self-healing materials. Many methods are used to trigger the release of encapsulated contents. Here we highlight mechanisms for the controlled release of encapsulated cargo that utilize chemical reactions occurring in solid polymeric shell walls. Triggering mechanisms responsible for covalent bond cleavage that result in the release of capsule contents include chemical, biological, light, thermal, magnetic, and electrical stimuli. We present methods for encapsulation and release, triggering methods, and mechanisms and conclude with our opinions on interesting obstacles for chemically induced activation with relevance for controlled release.

  1. Glenn Enters his Mercury Capsule

    NASA Technical Reports Server (NTRS)

    1962-01-01

    Astronaut John H. Glenn Jr. enters his Mercury capsule, 'Friendship 7' as he prepares for launch of the Mercury-Atlas rocket. On February 20, 1962 Glenn lifted off into space aboard his Mercury Atlas 6 (MA-6) rocket and became the first American to orbit the Earth. After orbiting the Earth 3 times, Friendship 7 landed in the Atlantic Ocean 4 hours, 55 minutes and 23 seconds later, just East of Grand Turk Island in the Bahamas. Glenn and his capsule were recovered by the Navy Destroyer Noa, 21 minutes after splashdown.

  2. Novel Aeromonas hydrophila PPD134/91 Genes Involved in O-Antigen and Capsule Biosynthesis

    PubMed Central

    Zhang, Y. L.; Arakawa, E.; Leung, K. Y.

    2002-01-01

    The sequences of the O-antigen and capsule gene clusters of the virulent Aeromonas hydrophila strain PPD134/91 were determined. The O-antigen gene cluster is 17,296 bp long and comprises 17 genes. Seven pathway genes for the synthesis of rhamnose and mannose, six transferase genes, one O unit flippase gene, and one O-antigen chain length determinant gene were identified by amino acid sequence similarity. PCR and Southern blot analysis were performed to survey the distribution of these 17 genes among 11 A. hydrophila strains of different serotypes. A. hydrophila PPD134/91 might belong to serotype O:18, as represented by JCM3980; it contained all the same O-antigen genes as JCM3980 (97 to 100% similarity at the DNA and amino acid levels). The capsule gene cluster of A. hydrophila PPD134/91 is 17,562 bp long and includes 13 genes, which were assembled into three distinct regions similar to those of the group II capsule gene cluster of Escherichia coli and other bacteria. Regions I and III contained four and two capsule transport genes, respectively. Region II had five genes which were highly similar to capsule synthesis pathway genes found in other bacteria. Both the purified O-antigen and capsular polysaccharides increased the ability of the avirulent A. hydrophila strain PPD35/85 to survive in naïve tilapia serum. However, the purified surface polysaccharides had no inhibitory effect on the adhesion of A. hydrophila PPD134/91 to carp epithelial cells. PMID:11953367

  3. Closeup View - Sigma "7" Capsule - Recovery Ship

    NASA Image and Video Library

    1962-10-03

    S62-06175 (3 Oct. 1962) --- Closeup view of the Mercury-Atlas 8 (MA-8) Sigma 7 capsule being lowered to recovery ship's deck. Navy personnel remove the floatation device before opening the capsule. Photo credit: NASA

  4. New frontiers in capsule endoscopy.

    PubMed

    Fireman, Zvi; Kopelman, Yael

    2007-08-01

    Capsule endoscopy (CE) was launched at the beginning of this millennium and has since become a well-established tool for evaluating the entire small bowel for manifold pathologies. CE far exceeded our early expectations by providing us with a tool to establish the correct diagnosis for elusive gastrointestinal (GI) conditions such as obscure GI bleeding, Crohn's disease, polyposis syndrome, and others. Recent evidence has shown CE to be superior to other imaging modalities, such as small bowel follow-through X-ray, colonoscopy with ileoscopy, computerized tomographic enterography, magnetic resonance enteroclysis, and push enteroscopy, for diagnosing small bowel pathologies. Gastroenterologists would prefer the convenience of a single capsule that can create images of the area from the oral cavity to the anal canal in one 'shot'. Because of anatomic and physiologic differences in the GI tract, however, it may not be possible to use the same capsule and so we would need a different one for each organ. In addition to the pioneer small bowel capsule, there is now an esophageal capsule, and a colonoscopy capsule will soon be available. The ideal CE should be capable of performing a biopsy or carrying out an online analysis (an 'optical' biopsy) and 'stop' bleeding by an epinephrine injection, a heat probe, argon plasma coagulation, etc. The ultimate capsule would include special detectors for white blood cells, and it would check oncological markers (e.g. CEA, CA 19-9), perform serology tests (e.g. antiendomysial, IgE), and measure various cytokines, pH levels, temperature and pressure, as well as deliver drugs. The capsule's motility feature in the small bowel may open a window to study the pathophysiology of relatively elusive medical entities, such as irritable bowel syndrome. The optimal capsule needs to contain an automatic computerized system for automatic detection of pathologies, such as that present in the ECG-Holter recording, in order to overcome the drawback

  5. A threading receptor for polysaccharides

    NASA Astrophysics Data System (ADS)

    Mooibroek, Tiddo J.; Casas-Solvas, Juan M.; Harniman, Robert L.; Renney, Charles M.; Carter, Tom S.; Crump, Matthew P.; Davis, Anthony P.

    2016-01-01

    Cellulose, chitin and related polysaccharides are key renewable sources of organic molecules and materials. However, poor solubility tends to hamper their exploitation. Synthetic receptors could aid dissolution provided they are capable of cooperative action, for example by multiple threading on a single polysaccharide molecule. Here we report a synthetic receptor designed to form threaded complexes (polypseudorotaxanes) with these natural polymers. The receptor binds fragments of the polysaccharides in aqueous solution with high affinities (Ka up to 19,000 M-1), and is shown—by nuclear Overhauser effect spectroscopy—to adopt the threading geometry. Evidence from induced circular dichroism and atomic force microscopy implies that the receptor also forms polypseudorotaxanes with cellulose and its polycationic analogue chitosan. The results hold promise for polysaccharide solubilization under mild conditions, as well as for new approaches to the design of biologically active molecules.

  6. Computer simulation and experimental study of the polysaccharide-polysaccharide interaction in the bacteria Azospirillum brasilense Sp245

    NASA Astrophysics Data System (ADS)

    Arefeva, Oksana A.; Kuznetsov, Pavel E.; Tolmachev, Sergey A.; Kupadze, Machammad S.; Khlebtsov, Boris N.; Rogacheva, Svetlana M.

    2003-09-01

    We have studied the conformational properties and molecular dynamics of polysaccharides by using molecular modeling methods. Theoretical and experimental results of polysaccharide-polysaccharide interactions are described.

  7. Sensor capsule for diagnosis of gastric disorders

    NASA Technical Reports Server (NTRS)

    Holen, J. T.

    1972-01-01

    Motility and pH sensor capsule is developed to monitor gastric acidity, pressure, and temperature. Capsule does not interfere with digestion. Sensor is capsule which includes pH electrode, Pitran pressure transducer, and thermistor temperature sensor all potted in epoxy and enclosed in high density polyethylene sheath.

  8. Mentoring. Information Capsule. Volume 0603

    ERIC Educational Resources Information Center

    Blazer, Christie

    2006-01-01

    Mentoring is a structured one-on-one relationship between an adult and youth that focuses on the needs of the youth, providing him or her with support, guidance, and assistance. This information capsule summarizes research findings on the impact of mentoring on factors such as academic achievement, social behaviors, attitudes, drug and alcohol…

  9. Capsulitis of the Second Toe

    MedlinePlus

    ... supportive ligaments weaken, leading to failure of the joint to stabilize the toe. The unstable toe drifts toward the big toe and eventually crosses over and lies on top of the big toe—resulting in crossover toe, the end stage of capsulitis. The symptoms of crossover toe ...

  10. Osmotic buckling of spherical capsules.

    PubMed

    Knoche, Sebastian; Kierfeld, Jan

    2014-11-07

    We study the buckling of elastic spherical shells under osmotic pressure with the osmolyte concentration of the exterior solution as a control parameter. We compare our results for the bifurcation behavior with results for buckling under mechanical pressure control, that is, with an empty capsule interior. We find striking differences for the buckling states between osmotic and mechanical buckling. Mechanical pressure control always leads to fully collapsed states with opposite sides in contact, whereas uncollapsed states with a single finite dimple are generic for osmotic pressure control. For sufficiently large interior osmolyte concentrations, osmotic pressure control is qualitatively similar to buckling under volume control with the volume prescribed by the osmolyte concentrations inside and outside the shell. We present a quantitative theory which also captures the influence of shell elasticity on the relationship between osmotic pressure and volume. These findings are relevant for the control of buckled shapes in applications. We show how the osmolyte concentration can be used to control the volume of buckled shells. An accurate analytical formula is derived for the relationship between the osmotic pressure, the elastic moduli and the volume of buckled capsules. This also allows use of elastic capsules as osmotic pressure sensors or deduction of elastic properties and the internal osmolyte concentration from shape changes in response to osmotic pressure changes. We apply our findings to published experimental data on polyelectrolyte capsules.

  11. Intact capture of hypervelocity projectiles

    NASA Technical Reports Server (NTRS)

    Tsou, P.

    1990-01-01

    The ability to capture projectiles intact at hypervelocities opens new applications in science and technology that would either not be possible or would be very costly by other means. This capability has been demonstrated in the laboratory for aluminum projectiles of 1.6 mm diameter, captured at 6 km/s, in one unmelted piece, and retaining up to 95% of the original mass. Furthermore, capture was accomplished passively using microcellular underdense polymer foam. Another advantage of capturing projectiles in an underdense medium is the ability of such a medium to preserve a record of the projectile's original velocity components of speed and direction. A survey of these experimental results is described in terms of a dozen parameters which characterize the amount of capture and the effect on the projectile due to different capture media.

  12. Intact capture of hypervelocity projectiles

    NASA Technical Reports Server (NTRS)

    Tsou, P.

    1990-01-01

    The ability to capture projectiles intact at hypervelocities opens new applications in science and technology that would either not be possible or would be very costly by other means. This capability has been demonstrated in the laboratory for aluminum projectiles of 1.6 mm diameter, captured at 6 km/s, in one unmelted piece, and retaining up to 95% of the original mass. Furthermore, capture was accomplished passively using microcellular underdense polymer foam. Another advantage of capturing projectiles in an underdense medium is the ability of such a medium to preserve a record of the projectile's original velocity components of speed and direction. A survey of these experimental results is described in terms of a dozen parameters which characterize the amount of capture and the effect on the projectile due to different capture media.

  13. Intact capture of hypervelocity projectiles.

    PubMed

    Tsou, P

    1990-01-01

    The ability to capture projectiles intact at hypervelocities opens new applications in science and technology that would either not be possible or would be very costly by other means. This capability has been demonstrated in the laboratory for aluminum projectiles of 1.6 mm diameter, captured at 6 km/s, in one unmelted piece, and retaining up to 95% of the original mass. Furthermore, capture was accomplished passively using microcellular underdense polymer foam. Another advantage of capturing projectiles in an underdense medium is the ability of such a medium to preserve a record of the projectile's original velocity components of speed and direction. A survey of these experimental results is described in terms of a dozen parameters which characterize the amount of capture and the effect on the projectile due to different capture media.

  14. Effect on bioavailability of admixing the contents of lansoprazole capsules with selected soft foods.

    PubMed

    Chun, A H; Erdman, K; Zhang, Y; Achari, R; Cavanaugh, J H

    2000-02-01

    This study was designed to compare the bioavailability of lansoprazole when administered as an intact capsule and when the contents are admixed with various soft foods. Patients sometimes cannot swallow or have difficulty swallowing intact capsules such as lansoprazole. To enable them to ingest the drug, the contents of the capsule can be admixed with small amounts of soft foods. Twenty-four healthy adult volunteers participated in this single-dose, 4-period crossover study by ingesting the contents of a 30-mg lansoprazole capsule that had been emptied into either a tablespoon of yogurt (regimen A), Ensure pudding (regimen B), or cottage cheese (regimen C), or given as an intact capsule (regimen D) during the first study period. The regimen assignments were rotated at weekly intervals so that each subject received each regimen. Blood samples were obtained over the 12-hour period after administration of each regimen, and pharmacokinetic parameters were determined. Of the 23 subjects who completed all 4 periods of the study, 18 were male and 5 were female. Their mean (+/- SD) age was 33.3+/-11.6 years, and their ages ranged from 19 to 52 years. No statistically significant differences between regimens were detected in mean maximum concentration, area under the curve (AUC) from time zero to the last measurable concentration, and AUC from time zero to infinity (AUC0-infinity) using analysis of variance. A statistically significant difference was detected in the time to maximum concentration between regimens C and D at 2.1 and 1.5 hours, respectively (P < or = 0.05). Bioavailability was assessed by the two 1-sided tests procedure using a 90% CI for the AUC0-infinity ratio of test-to-reference regimens. The 90% CIs were all within an acceptable equivalence range of 0.80 to 1.25. These results indicate similar bioavailabilities between the regimen in which the lansoprazole capsule was emptied and administration of the intact capsule. However, they may have limitations in

  15. In vitro fermentation characteristics of two mushroom species, an herb, and their polysaccharide fractions, using chicken cecal contents as inoculum.

    PubMed

    Guo, F C; Williams, B A; Kwakkel, R P; Verstegen, M W A

    2003-10-01

    In vitro fermentabilities of two mushrooms (Lentinus edodes--LenS; Tremella fuciformis--TreS), an herb (Astragalus membranaceus--AstS), and their polysaccharide fractions (LenE, TreE, and AstE) were investigated using microflora from chicken ceca. Polysaccharides were extracted using the hot water method. The mushrooms had lower polysaccharide yields (8 to 10%) than the herb (31%). Fermentation kinetics were determined using the in vitro cumulative gas production technique. End-products, such as gas, volatile fatty acids (VFA), and ammonia, were also determined. The gas profiles of intact materials were similar for AstS and LenS. The TreS had a diphasic digestion pattern. The extracts had similar profiles to the intact materials though gas production rates were faster. Intact materials tended to produce less VFA than the extracts though LenS and AstE had the highest total VFA production overall. Intact materials contained more protein than the extracts, and therefore resulted in more branched-chain fatty acids and ammonia. Fermentation kinetics and end-point products demonstrated differences in availability of substrates between the mushrooms and herb. These medicinal mushroom and herb materials, particularly their polysaccharide extracts, show promise in altering microbial activities and composition in chicken ceca. In vivo experiments are necessary for confirmation of this hypothesis.

  16. Identification of Klebsiella capsule synthesis loci from whole genome data

    PubMed Central

    Wick, Ryan R.; Gorrie, Claire; Jenney, Adam; Follador, Rainer; Thomson, Nicholas R.

    2016-01-01

    Klebsiella pneumoniae is a growing cause of healthcare-associated infections for which multi-drug resistance is a concern. Its polysaccharide capsule is a major virulence determinant and epidemiological marker. However, little is known about capsule epidemiology since serological typing is not widely accessible and many isolates are serologically non-typeable. Molecular typing techniques provide useful insights, but existing methods fail to take full advantage of the information in whole genome sequences. We investigated the diversity of the capsule synthesis loci (K-loci) among 2503 K. pneumoniae genomes. We incorporated analyses of full-length K-locus nucleotide sequences and also clustered protein-encoding sequences to identify, annotate and compare K-locus structures. We propose a standardized nomenclature for K-loci and present a curated reference database. A total of 134 distinct K-loci were identified, including 31 novel types. Comparative analyses indicated 508 unique protein-encoding gene clusters that appear to reassort via homologous recombination. Extensive intra- and inter-locus nucleotide diversity was detected among the wzi and wzc genes, indicating that current molecular typing schemes based on these genes are inadequate. As a solution, we introduce Kaptive, a novel software tool that automates the process of identifying K-loci based on full locus information extracted from whole genome sequences (https://github.com/katholt/Kaptive). This work highlights the extensive diversity of Klebsiella K-loci and the proteins that they encode. The nomenclature, reference database and novel typing method presented here will become essential resources for genomic surveillance and epidemiological investigations of this pathogen. PMID:28348840

  17. Preparation of polysaccharides from wax gourd.

    PubMed

    Huang, Gangliang; Tan, Jiantao; Tan, Xianchun; Peng, Daquan

    2011-08-01

    Preparation of polysaccharides from the wax gourd was studied. The crude polysaccharides were extracted by ethanol precipitation, and deproteinized by the hydrochloric acid method. The deproteinized polysaccharides were separated by column chromatography to obtain the pure polysaccharides. The pure polysaccharides have a β-D-pyranosidic bond, and their molecular weight distribution is about 22,500. It was indicated that the final product had much more purity by IR spectrum analysis, UV absorption spectrum analysis, and phenol-sulfuric acid method, respectively. It was proved that wax gourd polysaccharides were composed of rhamnose, xylose, arabinose, mannose, glucose, and galactose by thin layer chromatography.

  18. Chronological Aging Is Associated with Biophysical and Chemical Changes in the Capsule of Cryptococcus neoformans▿‡

    PubMed Central

    Cordero, Radames J. B.; Pontes, Bruno; Guimarães, Allan J.; Martinez, Luis R.; Rivera, Johanna; Fries, Bettina C.; Nimrichter, Leonardo; Rodrigues, Marcio L.; Viana, Nathan B.; Casadevall, Arturo

    2011-01-01

    Does the age of a microbial cell affect its virulence factors? To our knowledge, this question has not been addressed previously, but the answer is of great relevance for chronic infections where microbial cells persist and age in hosts. Cryptococcus neoformans is an encapsulated human-pathogenic fungus notorious for causing chronic infections where cells of variable age persist in tissue. The major virulence factor for C. neoformans is a polysaccharide (PS) capsule. To understand how chronological age could impact the cryptococcal capsule properties, we compared the elastic properties, permeabilities, zeta potentials, and glycosidic compositions of capsules from young and old cells and found significant differences in all parameters measured. Changes in capsular properties were paralleled by changes in PS molecular mass and density, as well as modified antigenic density and antiphagocytic properties. Remarkably, chronological aging under stationary-phase growth conditions was associated with the expression of α-1,3-glucans in the capsule, indicating a new structural capsular component. Our results establish that cryptococcal capsules are highly dynamic structures that change dramatically with chronological aging under prolonged stationary-phase growth conditions. Changes associated with cellular aging in chronic infections could contribute to the remarkable capacity of this fungus to persist in tissues by generating phenotypically and antigenically different capsules. PMID:21968999

  19. Two capsular polysaccharides enable Bacillus cereus G9241 to cause anthrax-like disease

    PubMed Central

    Oh, So-Young; Budzik, Jonathan M.; Garufi, Gabriella; Schneewind, Olaf

    2012-01-01

    Summary Bacillus cereus G9241 causes an anthrax-like respiratory illness in humans, however the molecular mechanisms of disease pathogenesis are not known. Genome sequencing identified two putative virulence plasmids proposed to provide for anthrax toxin (pBCXO1) and/or capsule expression (pBC218). We report here that B. cereus G9241 causes anthrax-like disease in immune-competent mice, which is dependent on each of the two virulence plasmids. pBCXO1 encodes pagA1, the homolog of anthrax protective antigen, as well as hasACB, providing for hyaluronic acid capsule formation, two traits that each contribute to disease pathogenesis. pBC218 harbors bpsX-H, Bacillus cereus exo-polysaccharide, which produce a second capsule. During infection, B. cereus G9241 elaborates both hasACB and bpsX-H capsules, which together are essential for the establishment of anthrax-like disease and the resistance of bacilli to phagocytosis. A single nucleotide deletion causes premature termination of hasA translation in B. anthracis, which is known to escape phagocytic killing by its pXO2 encoded poly-D-γ-glutamic acid (PDGA) capsule. Thus, multiple different gene clusters endow pathogenic bacilli with capsular material, provide for escape from innate host immune responses and aid in establishing the pathogenesis of anthrax-like disease. PMID:21371137

  20. Two capsular polysaccharides enable Bacillus cereus G9241 to cause anthrax-like disease.

    PubMed

    Oh, So-Young; Budzik, Jonathan M; Garufi, Gabriella; Schneewind, Olaf

    2011-04-01

    Bacillus cereus G9241 causes an anthrax-like respiratory illness in humans; however, the molecular mechanisms of disease pathogenesis are not known. Genome sequencing identified two putative virulence plasmids proposed to provide for anthrax toxin (pBCXO1) and/or capsule expression (pBC218). We report here that B. cereus G9241 causes anthrax-like disease in immune-competent mice, which is dependent on each of the two virulence plasmids. pBCXO1 encodes pagA1, the homologue of anthrax protective antigen, as well as hasACB, providing for hyaluronic acid capsule formation, two traits that each contribute to disease pathogenesis. pBC218 harbours bpsX-H, B. cereus exo-polysaccharide, which produce a second capsule. During infection, B. cereus G9241 elaborates both hasACB and bpsX-H capsules, which together are essential for the establishment of anthrax-like disease and the resistance of bacilli to phagocytosis. A single nucleotide deletion causes premature termination of hasA translation in Bacillus anthracis, which is known to escape phagocytic killing by its pXO2 encoded poly-d-γ-glutamic acid (PDGA) capsule. Thus, multiple different gene clusters endow pathogenic bacilli with capsular material, provide for escape from innate host immune responses and aid in establishing the pathogenesis of anthrax-like disease.

  1. A common pathway for O-linked protein-glycosylation and synthesis of capsule in Acinetobacter baumannii.

    PubMed

    Lees-Miller, Robert G; Iwashkiw, Jeremy A; Scott, Nichollas E; Seper, Andrea; Vinogradov, Evgeny; Schild, Stefan; Feldman, Mario F

    2013-09-01

    Multi-drug resistant strains of Acinetobacter baumannii are increasingly being isolated in hospitals worldwide. Among the virulence factors identified in this bacterium there is a general O-glycosylation system that appears to be important for biofilm formation and virulence, and the capsular polysaccharide, which is essential for resistance to complement killing. In this work, we identified a locus that is responsible for the synthesis of the O-pentasaccharide found on the glycoproteins. Besides the enzymes required for the assembly of the glycan, additional proteins typically involved in polymerization and transport of capsule were identified within or adjacently to the locus. Mutagenesis of PglC, the initiating glycosyltransferase prevented the synthesis of both glycoproteins and capsule, resulting in abnormal biofilm structures and attenuated virulence in mice. These results, together with the structural analysis of A. baumannii 17978 capsular polysaccharide via NMR, demonstrated that the pentasaccharides that decorate the glycoproteins are also the building blocks for capsule biosynthesis. Two linked subunits, but not longer glycan chains, were detected on proteins via MS. The discovery of a bifurcated pathway for O-glycosylation and capsule synthesis not only provides insight into the biology of A. baumannii but also identifies potential novel candidates for intervention against this emerging pathogen.

  2. Updated Campylobacter jejuni Capsule PCR Multiplex Typing System and Its Application to Clinical Isolates from South and Southeast Asia

    PubMed Central

    Poly, Frédéric; Serichantalergs, Oralak; Kuroiwa, Janelle; Pootong, Piyarat; Mason, Carl; Guerry, Patricia; Parker, Craig T.

    2015-01-01

    Campylobacter jejuni produces a polysaccharide capsule that is the major determinant of the Penner serotyping scheme. This passive slide agglutination typing system was developed in the early 1980’s and was recognized for over two decades as the gold standard for C. jejuni typing. A preliminary multiplex PCR technique covering 17 serotypes was previously developed in order to replace this classic serotyping scheme. Here we report the completion of the multiplex PCR technology that is able to identify all the 47 Penner serotypes types known for C. jejuni. The number of capsule types represented within the 47 serotypes is 35. We have applied this method to a collection of 996 clinical isolates from Thailand, Cambodia and Nepal and were able to successfully determine capsule types of 98% of these. PMID:26630669

  3. Triton shells of intact erythrocytes.

    PubMed

    Sheetz, M P; Sawyer, D

    1978-01-01

    About 40% of human erythrocyte membrane protein is resistant to solubilization in 0.5% Triton X-114. These components comprise a structure called a Triton shell roughly similar in size and shape to the original erythrocyte and thus constitute a cytoskeleton. With increasing concentrations of Triton the lipid content of the Triton shell decreases dramatically, whereas the majority of the protein components remain constant. Exceptions to this rule include proteins contained in band 3, the presumed anion channel, and in band 4 which decrease with increasing Triton concentration. The Triton-insoluble complex includes spectrin (bands 1 and 2), actin (band 5), and bands 3' and 7. Component 3' has an apparent molecular weight of 88,000 daltons as does 3; but unlike 3, it is insensitive to protease treatment of the intact cell, has a low extinction coefficient at 280 nm, and is solubilized from the shells in alkaline water solutions. Component 7 also has a low extinction coefficient at 280 nm. Spectrin alone is solubilized from the Triton shells in isotonic media. The solubilized spectrin contains no bound Triton and coelectrophoreses with spectrin eluted in hypotonic solutions from ghosts. Electron micrographs of fixed Triton shells stained with uranyl acetate show the presence of numerous filaments which appear beaded and are 80--120 A in diameter. The filaments cannot be composed mainly af actin, but enough spectrin is present to form the filaments. Triton shells may provide an excellent source of material useful in the investigation of the erythrocyte cytoskeleton.

  4. Intact Transition Epitope Mapping (ITEM)

    NASA Astrophysics Data System (ADS)

    Yefremova, Yelena; Opuni, Kwabena F. M.; Danquah, Bright D.; Thiesen, Hans-Juergen; Glocker, Michael O.

    2017-08-01

    Intact transition epitope mapping (ITEM) enables rapid and accurate determination of protein antigen-derived epitopes by either epitope extraction or epitope excision. Upon formation of the antigen peptide-containing immune complex in solution, the entire mixture is electrosprayed to translate all constituents as protonated ions into the gas phase. There, ions from antibody-peptide complexes are separated from unbound peptide ions according to their masses, charges, and shapes either by ion mobility drift or by quadrupole ion filtering. Subsequently, immune complexes are dissociated by collision induced fragmentation and the ion signals of the "complex-released peptides," which in effect are the epitope peptides, are recorded in the time-of-flight analyzer of the mass spectrometer. Mixing of an antibody solution with a solution in which antigens or antigen-derived peptides are dissolved is, together with antigen proteolysis, the only required in-solution handling step. Simplicity of sample handling and speed of analysis together with very low sample consumption makes ITEM faster and easier to perform than other experimental epitope mapping methods.

  5. Prolactin is associated with the development of photorefractoriness in intact, castrated, and testosterone-implanted starlings

    SciTech Connect

    Goldsmith, A.R.; Nicholls, T.J.

    1984-05-01

    Using radioimmunoassays, prolactin, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured in the plasma of intact, castrated, and testosterone-implanted male starlings. Two groups of birds (intact and castrated males) were transferred when photosensitive from short (8-hr) to long (16-hr) day lengths; in both cases plasma prolactin levels increased steadily reaching a peak after 5 weeks of photostimulation, at the time of the onset of photorefractoriness. Three groups (intacts, castrates, and castrates implanted with Silastic capsules containing testosterone) were exposed to day lengths increasing by 30 min per week from 8 to 16 hr. Again, prolactin levels increased in a similar fashion in all three groups at the time of refractoriness, which occurred when the day length reached 15-16 hr. Thus the timing of photorefractoriness and the associated rise in prolactin secretion which occur in response to photostimulation do not depend upon the presence of the gonads and are not affected when testosterone is maintained at a constant high level. Nor is the increase in prolactin altered when the cycle of gonadotrophin secretion which normally precedes it is completely suppressed by the implantation of a testosterone capsule. It would seem that prolactin secretion in the starling is stimulated by transfer from short to long day lengths, but not as a consequence of high gonadotrophin or androgen secretion rates.

  6. Reactor for making uniform capsules

    NASA Technical Reports Server (NTRS)

    Wang, Taylor G. (Inventor); Anikumar, Amrutur V. (Inventor); Lacik, Igor (Inventor)

    1999-01-01

    The present invention provides a novel reactor for making capsules with uniform membrane. The reactor includes a source for providing a continuous flow of a first liquid through the reactor; a source for delivering a steady stream of drops of a second liquid to the entrance of the reactor; a main tube portion having at least one loop, and an exit opening, where the exit opening is at a height substantially equal to the entrance. In addition, a method for using the novel reactor is provided. This method involves providing a continuous stream of a first liquid; introducing uniformly-sized drops of the second liquid into the stream of the first liquid; allowing the drops to react in the stream for a pre-determined period of time; and collecting the capsules.

  7. Preparation of Burkholderia pseudomallei Polysaccharide-CRM197 Conjugate, a Potential Vaccine Candidate for Glanders and Melioidosis

    DTIC Science & Technology

    2005-10-01

    Acetolysis- 2 % HAc, 1000 C, 2h: – Cleaves the linkage at KDO in LPS to release lipid A, core oligosaccharides, and O-antigens (repeating sugar units...display a currently valid OMB control number. 1. REPORT DATE 01 OCT 2005 2 . REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE...Western blot: – Polysaccharide-protein conjugate, Antibody produced against the whole cells, capsule, LPS Rationale for Choosing a Protein Carrier To

  8. The Antioxidant Activities of Natural Polysaccharides.

    PubMed

    Huang, Gangliang; Mei, Xinya; Hu, Jinchuan

    2017-01-01

    The natural polysaccharides contain plant polysaccharides, animal polysaccharides and microbial polysaccharides. They are a kind of biological macromolecules with immune regulation, anti-tumor, anti-radiation, anti-inflammation, anti-fatigue and anti-aging effects. These effects are related to their antioxidant properties. The action mechanisms of antioxidation and scavenging free radicals for natural polysaccharides were reviewed. The recent research progresses and our work on antioxidant properties of polysaccharides and their derivatives were summarized. At last, the existing problems of antioxidant polysaccharides were analyzed, and the development prospects were also presented. It is important to study the antioxidant activities of polysaccharides and their derivatives for the development of natural antioxidants. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  9. Capsular Polysaccharide Expression in Commensal Streptococcus Species: Genetic and Antigenic Similarities to Streptococcus pneumoniae.

    PubMed

    Skov Sørensen, Uffe B; Yao, Kaihu; Yang, Yonghong; Tettelin, Hervé; Kilian, Mogens

    2016-11-15

    Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule production distinguishes S. pneumoniae from closely related commensals of the mitis group streptococci. Based on antigenic and genetic analyses of 187 mitis group streptococci, including 90 recognized serotypes of S. pneumoniae, we demonstrated capsule production by the Wzy/Wzx pathway in 74% of 66 S. mitis strains and in virtually all tested strains of S. oralis (subspecies oralis, dentisani, and tigurinus) and S. infantis Additional analyses of genomes of S. cristatus, S. parasanguinis, S. australis, S. sanguinis, S. gordonii, S. anginosus, S. intermedius, and S. constellatus revealed complete capsular biosynthesis (cps) loci in all strains tested. Truncated cps loci were detected in three strains of S. pseudopneumoniae, in 26% of S. mitis strains, and in a single S. oralis strain. The level of sequence identities of cps locus genes confirmed that the structural polymorphism of capsular polysaccharides in S. pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S. pneumoniae raises concerns about potential misidentifications in addition to important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and for the pathogen. Expression of a capsular polysaccharide is among the principal virulence factors of Streptococcus pneumoniae and is the basis for successful vaccines against infections caused by this important pathogen. Contrasting with previous

  10. Pbx Proteins in Cryptococcus neoformans Cell Wall Remodeling and Capsule Assembly

    PubMed Central

    Kumar, Pardeep; Heiss, Christian; Santiago-Tirado, Felipe H.; Black, Ian; Azadi, Parastoo

    2014-01-01

    The cryptococcal capsule is a critical virulence factor of an important pathogen, but little is known about how it is associated with the cell or released into the environment. Two mutants lacking PBX1 and PBX2 were found to shed reduced amounts of the capsule polysaccharide glucuronoxylomannan (GXM). Nuclear magnetic resonance, composition, and physical analyses showed that the shed material was of normal mass but was slightly enriched in xylose. In contrast to previous reports, this material contained no glucose. Notably, the capsule fibers of pbxΔ mutant cells grown under capsule-inducing conditions were present at a lower than usual density and were loosely attached to the cell wall. Mutant cell walls were also defective, as indicated by phenotypes including abnormal cell morphology, reduced mating filamentation, and altered cell integrity. All observed phenotypes were shared between the two mutants and exacerbated in a double mutant. Consistent with a role in surface glycan synthesis, the Pbx proteins localized to detergent-resistant membrane domains. These results, together with the sequence motifs in the Pbx proteins, suggest that Pbx1 and Pbx2 are redundant proteins that act in remodeling the cell wall to maintain normal cell morphology and precursor availability for other glycan synthetic processes. Their absence results in aberrant cell wall growth and metabolic imbalance, which together impact cell wall and capsule synthesis, cell morphology, and capsule association. The surface changes also lead to increased engulfment by host phagocytes, consistent with the lack of virulence of pbx mutants in animal models. PMID:24585882

  11. Capsule endoscopy: The road ahead

    PubMed Central

    Singeap, Ana-Maria; Stanciu, Carol; Trifan, Anca

    2016-01-01

    Since its introduction into clinical practice 15 years ago, capsule endoscopy (CE) has become the first-line investigation procedure in some small bowel pathologies, and more recently, dedicated esophageal and colon CE have expanded the fields of application to include the upper and lower gastrointestinal disorders. During this time, CE has become increasingly popular among gastroenterologists, with more than 2 million capsule examinations performed worldwide, and nearly 3000 PubMed-listed studies on its different aspects published. This huge interest in CE may be explained by its non-invasive nature, patient comfort, safety, and access to anatomical regions unattainable via conventional endoscopy. However, CE has several limitations which impede its wider clinical applications, including the lack of therapeutic capabilities, inability to obtain biopsies and control its locomotion. Several research groups are currently working to overcome these limitations, while novel devices able to control capsule movement, obtain high quality images, insufflate the gut lumen, perform chromoendoscopy, biopsy of suspect lesions, or even deliver targeted drugs directly to specific sites are under development. Overlooking current limitations, especially as some of them have already been successfully surmounted, and based on the tremendous progress in technology, it is expected that, by the end of next 15 years, CE able to perform both diagnostic and therapeutic procedures will remain the major form of digestive endoscopy. This review summarizes the literature that prognosticates about the future developments of CE. PMID:26755883

  12. Rheologically interesting polysaccharides from yeasts

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Nelson, G. A.; Cathey, C. A.; Fuller, G. G.

    1989-01-01

    We have examined the relationships between primary, secondary, and tertiary structures of polysaccharides exhibiting the rheological property of friction (drag) reduction in turbulent flows. We found an example of an exopolysaccharide from the yeast Cryptococcus laurentii that possessed high molecular weight but exhibited lower than expected drag reducing activity. Earlier correlations by Hoyt showing that beta 1 --> 3, beta 2 --> 4, and alpha 1 --> 3 linkages in polysaccharides favored drag reduction were expanded to include correlations to secondary structure. The effect of sidechains in a series of gellan gums was shown to be related to sidechain length and position. Disruption of secondary structure in drag reducing polysaccharides reduced drag reducing activity for some but not all exopolysaccharides. The polymer from C. laurentii was shown to be more stable than xanthan gum and other exopolysaccharides under the most vigorous of denaturing conditions. We also showed a direct relationship between extensional viscosity measurements and the drag reducing coefficient for four exopolysaccharides.

  13. Rheologically interesting polysaccharides from yeasts

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Nelson, G. A.; Cathey, C. A.; Fuller, G. G.

    1989-01-01

    We have examined the relationships between primary, secondary, and tertiary structures of polysaccharides exhibiting the rheological property of friction (drag) reduction in turbulent flows. We found an example of an exopolysaccharide from the yeast Cryptococcus laurentii that possessed high molecular weight but exhibited lower than expected drag reducing activity. Earlier correlations by Hoyt showing that beta 1 --> 3, beta 2 --> 4, and alpha 1 --> 3 linkages in polysaccharides favored drag reduction were expanded to include correlations to secondary structure. The effect of sidechains in a series of gellan gums was shown to be related to sidechain length and position. Disruption of secondary structure in drag reducing polysaccharides reduced drag reducing activity for some but not all exopolysaccharides. The polymer from C. laurentii was shown to be more stable than xanthan gum and other exopolysaccharides under the most vigorous of denaturing conditions. We also showed a direct relationship between extensional viscosity measurements and the drag reducing coefficient for four exopolysaccharides.

  14. Allelic Variation of the Capsule Promoter Diversifies Encapsulation and Virulence In Streptococcus pneumoniae

    PubMed Central

    Wen, Zhensong; Liu, Yanni; Qu, Fen; Zhang, Jing-Ren

    2016-01-01

    The polysaccharide capsule is the major virulence factor of Streptococcus pneumoniae (pneumococcus), a major human pathogen. The sequences in the promoter and coding regions of the capsule gene locus undergo extensive variations through the natural transformation-mediated horizontal gene transfer. The sequence variations in the coding region have led to at least 97 capsular serotypes. However, it remains unclear whether the sequence polymorphisms in the promoter region have any biological significance. In this study, we determined the sequences of the cps promoter region from 225 invasive pneumococcal isolates, and identified modular composition and remarkable inter-strain sequence variations in this region. The strain-to strain variations in the cps promoter are characterized by diversity in sequence and size, mosaic combinations of nucleotide polymorphisms and sequence modules, selective preservation of the sequence combinations, and promiscuous assortments of the sequences between the promoter and coding regions. Isogenic pneumococci carrying allelic variants of the cps promoter displayed significant differences in the transcription of the capsule genes, capsule production, adhesion to host epithelial cells, anti-phagocytosis and virulence in mouse bacteremia model. This study has thus indicated that the sequence polymorphisms in the cps promoter represent a novel mechanism for fine-tuning the level of encapsulation and virulence among S. pneumoniae strains. PMID:27465908

  15. The K1 Capsular Polysaccharide of Acinetobacter baumannii Strain 307-0294 Is a Major Virulence Factor ▿

    PubMed Central

    Russo, Thomas A.; Luke, Nicole R.; Beanan, Janet M.; Olson, Ruth; Sauberan, Shauna L.; MacDonald, Ulrike; Schultz, L. Wayne; Umland, Timothy C.; Campagnari, Anthony A.

    2010-01-01

    Acinetobacter baumannii is a pathogen of increasing medical importance with a propensity to be multidrug resistant, thereby making treatment challenging. Little is known of virulence traits in A. baumannii. To identify virulence factors and potential drug targets, random transposon (Tn) mutants derived from the A. baumannii strain AB307-0294 were screened to identify genes essential for growth in human ascites fluid in vitro, an inflammatory exudative fluid. These studies led to the identification of two genes that were predicted to be required for capsule polymerization and assembly. The first, ptk, encodes a putative protein tyrosine kinase (PTK), and the second, epsA, encodes a putative polysaccharide export outer membrane protein (EpsA). Monoclonal antibodies used in flow cytometric and Western analyses confirmed that these genes are required for a capsule-positive phenotype. A capsule-positive phenotype significantly optimized growth in human ascites fluid, survival in human serum, and survival in a rat soft tissue infection model. Importantly, the clearance of the capsule-minus mutants AB307.30 (ptk mutant, capsule minus) and AB307.45 (epsA mutant, capsule minus) was complete and durable. These data demonstrated that the K1 capsule from AB307-0294 was an important protectin. Further, these data suggested that conserved proteins, which contribute to the capsule-positive phenotype, are potential antivirulence drug targets. Therefore, the results from this study have important biologic and translational implications and, to the best of our knowledge, are the first to address the role of capsule in the pathogenesis of A. baumannii infection. PMID:20643860

  16. Simulations of laser imprint for Nova experiments and for ignition capsules. Revision 1

    SciTech Connect

    Weber, S.V.; Glendinning, S.G.; Kalantar, D.H.; Key, M.H.; Remington, B.A.; Rothenberg, J.L.; Wolfrum, E.; Verdon, C.P.; Knauer, J.P.

    1996-12-01

    In direct drive ICF, nonuniformities in laser illumination seed ripples at the ablation front in a process called ``imprint``. These nonuniformities grow during the capsule implosion and, if initially large enough, can penetrate the capsule shell, impede ignition, or degrade burn. Imprint has been simulated for recent experiments performed on the Nova laser at LLNL examining a variety of beam smoothing conditions. Most used laser intensities similar to the early part of an ignition capsule pulse shape, 1 {approx_equal} 10{sup 13} W/cm{sup 2} . The simulations matched most of the measurements of imprint modulation. The effect of imprint upon National Ignition Facility (NIF) direct drive ignition capsules has also been simulated. Imprint is predicted to give modulation comparable to an intrinsic surface finish of {approximately}10 nm RMS. Modulation growth was examined using the Haan [Phys. Rev. A {bold 39}, 5812 (1989)] model, with linear growth factors as a function of spherical harmonic mode number obtained from an analytic dispersion relation. Ablation front amplitudes are predicted to become substantially nonlinear, so that saturation corrections are large. Direct numerical simulations of two-dimensional multimode growth were also performed. The capsule shell is predicted to remain intact, which gives a basis for believing that ignition can be achieved. 27 refs., 10 figs.

  17. Simulations of laser imprint for Nova experiments and for ignition capsules

    SciTech Connect

    Weber, S.V.; Glendinning, S.G.; Kalantar, D.H.; Key, M.H.; Remington, B.A.; Rothenberg, J.E.; Wolfrum, E.; Verdon, C.P.; Knauer, J.P.

    1996-11-08

    In direct drive ICF, nonuniformities in laser illumination seed ripples at the ablation front in a process called imprint. These non nonuniformities grow during the capsule implosion and, if initially large enough, can penetrate the capsule shell, impede ignition, or degrade burn. Imprint has been simulated for recent experiments performed on the Nova laser at LLNL examining a variety of beam smoothing conditions. Most used laser intensities similar to the early part of an ignition capsule pulse shape, I=10X13 W/cm3. The simulations matched most of the measurements of imprint modulation. The effect of imprint upon National Ignition Facility (NIF) direct drive ignition capsules has also been simulated. Imprint is predicted to give modulation comparable to an intrinsic surface finish of 10 nm RMS. Modulation growth was examined using the Haan model, with linear growth as a function of spherical harmonic mode number obtained from an analytic dispersion relation. Ablation front amplitudes are predicted to become substantially nonlinear, so that saturation corrections are large. Direct numerical simulations of two- dimensional multimode growth were also performed. The capsule shell is predicted to remain intact, which gives a basis for believing that ignition can be achieved.

  18. A Universal Protocol for Photochemical Covalent Immobilization of Intact Carbohydrates for the Preparation of Carbohydrate Microarrays

    PubMed Central

    Wang, Huibin; Zhang, Yiming; Yuan, Xun; Chen, Yi; Yan, Mingdi

    2010-01-01

    A universal photochemical method has been established for the immobilization of intact carbohydrates and their analogues, and for the fabrication of carbohydrate microarrays. The method features the use of perfluorophenyl azide (PFPA)-modified substrates and the photochemical reaction of surface azido groups with printed carbohydrates. Various aldoses, ketoses, non-reducing sugars such as alditols and their derivatives can be directly arrayed on the PFPA-modified chips. The lectin-recognition ability of arrayed mannose, glucose and their oligo- and polysaccharides were confirmed using surface plasmon resonance imaging and laser-induced fluorescence imaging. PMID:21138274

  19. Broad-spectrum biofilm inhibition by a secreted bacterial polysaccharide

    PubMed Central

    Valle, Jaione; Da Re, Sandra; Henry, Nelly; Fontaine, Thierry; Balestrino, Damien; Latour-Lambert, Patricia; Ghigo, Jean-Marc

    2006-01-01

    The development of surface-attached biofilm bacterial communities is considered an important source of nosocomial infections. Recently, bacterial interference via signaling molecules and surface active compounds was shown to antagonize biofilm formation, suggesting that nonantibiotic molecules produced during competitive interactions between bacteria could be used for biofilm reduction. Hence, a better understanding of commensal/pathogen interactions within bacterial community could lead to an improved control of exogenous pathogens. To reveal adhesion or growth-related bacterial interference, we investigated interactions between uropathogenic and commensal Escherichia coli in mixed in vitro biofilms. We demonstrate here that the uropathogenic strain CFT073 and all E. coli expressing group II capsules release into their environment a soluble polysaccharide that induces physicochemical surface alterations, which prevent biofilm formation by a wide range of Gram-positive and Gram-negative bacteria. We show that the treatment of abiotic surfaces with group II capsular polysaccharides drastically reduces both initial adhesion and biofilm development by important nosocomial pathogens. These findings identify capsular polymers as antiadhesion bacterial interference molecules, which may prove to be of significance in the design of new strategies to limit biofilm formation on medical in dwelling devices. PMID:16894146

  20. 46 CFR 174.185 - Intact stability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Intact stability. 174.185 Section 174.185 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Offshore Supply Vessels § 174.185 Intact stability. (a...

  1. 46 CFR 172.070 - Intact stability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Intact stability. 172.070 Section 172.070 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO... § 172.070 Intact stability. All tank vessels of 5,000 DWT and above contracted after the effective date...

  2. 46 CFR 172.070 - Intact stability.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Intact stability. 172.070 Section 172.070 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO... § 172.070 Intact stability. All tank vessels of 5,000 deadweight tons (DWT) and above, contracted after...

  3. 46 CFR 174.015 - Intact stability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Intact stability. 174.015 Section 174.015 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Deck Cargo Barges § 174.015 Intact stability. (a) Except...

  4. 46 CFR 174.015 - Intact stability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Intact stability. 174.015 Section 174.015 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Deck Cargo Barges § 174.015 Intact stability. (a) Except...

  5. 46 CFR 172.070 - Intact stability.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Intact stability. 172.070 Section 172.070 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO... § 172.070 Intact stability. All tank vessels of 5,000 deadweight tons (DWT) and above, contracted after...

  6. 46 CFR 172.070 - Intact stability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Intact stability. 172.070 Section 172.070 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO... § 172.070 Intact stability. All tank vessels of 5,000 deadweight tons (DWT) and above, contracted after...

  7. 46 CFR 174.185 - Intact stability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Intact stability. 174.185 Section 174.185 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Offshore Supply Vessels § 174.185 Intact stability. (a...

  8. 46 CFR 172.070 - Intact stability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Intact stability. 172.070 Section 172.070 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO... § 172.070 Intact stability. All tank vessels of 5,000 deadweight tons (DWT) and above, contracted after...

  9. Therapeutic mechanism of ginkgo biloba exocarp polysaccharides on gastric cancer

    PubMed Central

    Xu, Ai-Hua; Chen, Hua-Sheng; Sun, Bu-Chan; Xiang, Xiao-Ren; Chu, Yun-Fei; Zhai, Fan; Jia, Ling-Chang

    2003-01-01

    AIM: To study the therapeutic mechanism of Ginkgo biloba exocarp polysaccharides (GBEP) on gastric cancer. METHODS: Thirty patients with gastric cancer were treated with oral GBEP capsules. The area of tumors was measured by electron gastroscope before and after treatment, then the inhibitory and effective rates were calculated. The ultrastructures of tumor cells were examined by transmissional electron microscope. Cell culture, MTT, flow cytometry were performed to observe proliferation, apoptosis and changes of relevant gene expression of human gastric cancer SGC-7901 cells. RESULTS: Compared with the statement before treatment, GBEP capsules could reduce the area of tumors, and the effective rate was 73.4%. Ultrastructural changes of the cells indicated that GBEP could induce apoptosis and differentiation in tumor cells of patients with gastric cancer. GBEP could inhibit the growth of human gastric cancer SGC-7901 cells following 24-72 h treatment in vitro at 10-320 mg/L, which was dose- and time-dependent. GBEP was able to elevate the apoptosis rate and expression of c-fos gene, but reduce the expression of c-myc and bcl-2 genes also in a dose-dependent manner. CONCLUSION: The therapeutic mechanism of GBEP on human gastric cancer may relate to its effects on the expression of c-myc, bcl-2 and c-fos genes, which can inhibit proliferation and induce apoptosis and differentiation of tumor cells. PMID:14606069

  10. Poly(N-isopropylacrylamide)/poly(dopamine) capsules.

    PubMed

    Zhang, Yan; Teo, Boon M; Goldie, Kenneth N; Städler, Brigitte

    2014-05-20

    Polymer capsules are an interesting concept considered in nanobiotechnology. Approaches that facilitate their assembly remain sought after. Poly(dopamine) (PDA) has been considered and successfully applied in this context. We recently demonstrated that PDA could be copolymerized with different types of poly(N-isopropylacrylamide) (pNiPAAm) to assemble mixed films on planar substrates. Herein, we transferred this approach onto colloidal substrates and characterized the film thickness depending on the film composition and template particles size. While the membrane of capsules assembled using 5 μm template particles exhibited strong dependency on the film composition, smaller templates led to capsules with similar membrane thickness. We then compared the permeability of different capsules using fluorescently labeled dextran and fluorescein. We found that the permeability of capsules was heavily dependent on the polymer composition and the template particle size. These fundamental findings contribute to the potential of these capsules, assembled in one-step, for biomedical applications.

  11. Capsule endoscopy in 2005: facts and perspectives.

    PubMed

    Delvaux, Michel; Gérard Gay

    2006-02-01

    Capsule endoscopy has recently been introduced to explore endoscopically the whole small intestine, fulfilling a gap between examinations of the upper and lower gastrointestinal tract. The technique consists of a miniaturized endoscope, embedded in a swallowable capsule that is propulsed by peristalsis and achieves the journey to the right colon in five to eight hours. Images captured by the capsule are recorded on a hard drive worn in a belt by the patient. The main indication for capsule examination is the examination of the small bowel to find a bleeding lesion in patients with obscure bleeding. Several studies have shown that the diagnostic yield of capsule endoscopy is superior to that of push enteroscopy in this indication. Other possible indications are patients with suspected intestinal location of Crohn's disease, familial adenomatous polyposis, complicated coeliac disease and lesions due NSAIDs. The review contains information on the technical aspects of capsule endoscopy and discusses the indications. Issues of safety and tolerance are also discussed.

  12. Perform Ultrasonic Testing on Cs Capsule Overpacks

    SciTech Connect

    DAVIS, S.J.

    2000-04-06

    This procedure provides a safe, uniform method for the performance of the ultrasonic weld inspection of the Cesium capsule overpacks. The inspection system will detect cracks, lack of fusion, and lack of penetration. This computer controlled automated system will perform the examination once the capsule overpack has been placed in the pool cell. Examination of the capsule overpacks will be in accordance with drawing H-283014, REV. 0 ,and a certified NDE examiner will perform the test procedure, provide analysis, and test documentation.

  13. Postoperative radiation and implant capsule contraction

    SciTech Connect

    Caffee, H.H.; Mendenhall, N.P.; Mendenhall, W.M.; Bova, F.J.

    1988-01-01

    Occasionally radiation is required as adjunctive therapy following mastectomy for breast cancer. The effects of radiation on a developing implant capsule are unknown, but they are very important in relation to the increased use of immediate reconstruction. Experiments were performed on rabbits to study the effects of postoperative radiation therapy on capsule contraction and thickness. The results of these experiments suggest that radiation has no effect on implant capsules.

  14. Organ cultures and kidney-capsule grafting of tooth germs.

    PubMed

    Otsu, Keishi; Fujiwara, Naoki; Harada, Hidemitsu

    2012-01-01

    The study of organogenesis allows investigation of a variety of basic biological processes in the context of the intact organ. The ability to analyze teeth ex vivo during development has emerged as a powerful tool to understand how teeth are constructed and the signaling pathways that regulate these developmental processes. Here, we describe in detail our protocols for organ culture and kidney-capsule grafting of mouse tooth germs. These techniques allow us to reproduce the developmental process of tooth germs and estimate the effect of specific genes ex vivo, as well as are a tool for studies on the mechanisms of normal and abnormal tooth morphogenesis. They may also be applied to studies on other aspects of developmental biology and regenerative medicine.

  15. Polysaccharide-Modified Synthetic Polymeric Biomaterials

    PubMed Central

    Baldwin, Aaron D.; Kiick, Kristi L.

    2010-01-01

    This review presents an overview of polysaccharide-conjugated synthetic polymers and their use in tissue-engineered scaffolds and drug-delivery applications. This topic will be divided into four categories: (1) polymeric materials modified with non-mammalian polysaccharides such as alginate, chitin, and dextran; (2) polymers modified with mammalian polysaccharides such as hyaluronan, chondroitin sulfate, and heparin; (3) multi-polysaccharide-derivatized polymer conjugate systems; and (4) polymers containing polysaccharide-mimetic molecules. Each section will discuss relevant conjugation techniques, analysis, and the impact of these materials as micelles, particles, or hydrogels used in in-vitro and in-vivo biomaterial applications. PMID:20091875

  16. Polysaccharide-modified synthetic polymeric biomaterials.

    PubMed

    Baldwin, Aaron D; Kiick, Kristi L

    2010-01-01

    This review presents an overview of polysaccharide-conjugated synthetic polymers and their use in tissue-engineered scaffolds and drug-delivery applications. This topic will be divided into four categories: (1) polymeric materials modified with non-mammalian polysaccharides such as alginate, chitin, and dextran; (2) polymers modified with mammalian polysaccharides such as hyaluronan, chondroitin sulfate, and heparin; (3) multi-polysaccharide-derivatized polymer conjugate systems; and (4) polymers containing polysaccharide-mimetic molecules. Each section will discuss relevant conjugation techniques, analysis, and the impact of these materials as micelles, particles, or hydrogels used in in-vitro and in-vivo biomaterial applications. (c) 2010 Wiley Periodicals, Inc.

  17. Duodenum identification mechanism for capsule endoscopy.

    PubMed

    Woo, Sang Hyo; Mohy-Ud-Din, Zia; Cho, Jin Ho

    2011-04-01

    The aim of this study is to implement a duodenum identification mechanism for capsule endoscopes because commercially available capsule endoscopes sometimes present a false negative diagnosis of the duodenum. One reason for the false negative diagnosis is that the duodenum is the fastest moving part within the gastrointestinal tract and the current frame rate of the capsule is not fast enough. When the capsule can automatically identify that it is in the duodenum, the frame rate of the capsule can be temporarily increased to reduce the possibility of a false negative diagnosis. This study proposes a mechanism to identify the duodenum using capacitive proximity sensors that can distinguish the surrounding tissue and transmit data using RF communication. The implemented capsule (D11 mm × L22 mm) was smaller than the commercially available capsule endoscopes, and power consumption was as low as 0.642 mW. Preexperiments were conducted to select an appropriate electrode width in order to increase the signal-to-noise ratio (SNR), and in vitro experiments were conducted to verify whether the implemented capsule could identify the duodenum within 3 s. The experiment showed that the identification rate of duodenum was 93% when the velocity of the capsule was less than 1 cm/s.

  18. A Laboratory Exercise in Capsule Making

    PubMed Central

    2008-01-01

    Objective To create and implement a compounding laboratory exercise utilizing a variety of techniques and equipment. Design A 3-hour laboratory exercise on preparing compound prescriptions for capsules was developed and taught to first-year doctor of pharmacy (PharmD) students. Students completed appropriate preparations and calculation of ingredients and prepared capsules using a hand-packing technique and a capsule-filling machine. The students then individually weighed the capsules and performed batch testing for uniformity. Assessment Ninety-six percent of the students who completed the laboratory performed the necessary calculations for machine-prepared capsules correctly and 100% completed the calculations for the hand-filled capsules correctly. With the hand-filled capsules, 100% of the students processed all 4 units within ±5% of the stated capsule weight and capsules were deemed successful and accurate. Conclusion Students acquired a firm grasp of basic compounding techniques and the skills to prepare accurate, safe, and uniform dosage forms for patients. PMID:19214273

  19. Polysaccharides templates for assembly of nanosilver.

    PubMed

    Emam, Hossam E; Ahmed, Hanan B

    2016-01-01

    Polysaccharides are particularly attractive in biomedical applications due to its biodegradability and biocompatibility. In addition to its ecofriendly effects and easy processing into different hydrogel shapes, made polysaccharides used on a large scale as suitable media for preparation of silver nanoparticles (AgNPs). In spite of, most of polysaccharides are water insoluble, but it has shown to be quite efficient capping agents and/or nanoreactor matrices for production of AgNPs. Several methods have been developed to get the benefit of multi-functionality for polysaccharides' macromolecules in preparation of AgNPs. Therefore, recently, preparation of nanosilver using different polysaccharides have been the focus of an exponentially increasing number of works devoted to develop nanocomposites by blending AgNPs with different polysaccharides matrices. The current review represents a wide survey for the published studies which interested in using of polysaccharides in nanosilver preparations.

  20. Capsular Polysaccharide Expression in Commensal Streptococcus Species: Genetic and Antigenic Similarities to Streptococcus pneumoniae

    PubMed Central

    Skov Sørensen, Uffe B.; Yao, Kaihu; Yang, Yonghong; Tettelin, Hervé

    2016-01-01

    ABSTRACT Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule production distinguishes S. pneumoniae from closely related commensals of the mitis group streptococci. Based on antigenic and genetic analyses of 187 mitis group streptococci, including 90 recognized serotypes of S. pneumoniae, we demonstrated capsule production by the Wzy/Wzx pathway in 74% of 66 S. mitis strains and in virtually all tested strains of S. oralis (subspecies oralis, dentisani, and tigurinus) and S. infantis. Additional analyses of genomes of S. cristatus, S. parasanguinis, S. australis, S. sanguinis, S. gordonii, S. anginosus, S. intermedius, and S. constellatus revealed complete capsular biosynthesis (cps) loci in all strains tested. Truncated cps loci were detected in three strains of S. pseudopneumoniae, in 26% of S. mitis strains, and in a single S. oralis strain. The level of sequence identities of cps locus genes confirmed that the structural polymorphism of capsular polysaccharides in S. pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S. pneumoniae raises concerns about potential misidentifications in addition to important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and for the pathogen. PMID:27935839

  1. Equilibrium ignition for ICF capsules

    SciTech Connect

    Lackner, K.S.; Colgate, S.A.; Johnson, N.L.; Kirkpatrick, R.C.; Menikoff, R.; Petschek, A.G. )

    1994-10-05

    In comparing high-gain ICF targets using cryogenic DT for a pusher with equilibrium ignition targets using high-[ital Z] pushers which contain the radiation, we point to the intrinsic advantages of the latter. Equilibrium or volume ignition sacrifices high gain for lower losses, lower ignition temperature, lower implosion velocity, and lower sensitivity of the more robust capsule to small fluctuations and asymmetries in the drive system. The reduction in gain is about a factor of 2.5, which is small enough to make the more robust equilibrium ignition an atractive alternative. [copyright] 1994 [ital American] [ital Institute] [ital of] [ital Physics

  2. Genesis Sample Return Capsule Overview

    NASA Technical Reports Server (NTRS)

    Willcockson, Bill

    2005-01-01

    I. Simple Entry Capsule Concept: a) Spin-Stabilized/No Active Control Systems; b) Ballistic Entry for 11.04 km/sec Velocity; c) No Heatshield Separation During Entry; d) Parachute Deploy via g-Switch + Timer. II. Stardust Design Inheritance a) Forebody Shape; b) Seal Concepts; c) Parachute Deploy Control; d) Utah Landing Site (UTTR). III. TPS Systems a) Heatshield - Carbon-Carbon - First Planetary Entry; b) Backshell - SLA-561V - Flight Heritage from Pathfinder, MER; d) Forebody Structural Penetrations Aerothermal and TPS Design Process has the Same Methodology as Used for Pathfinder, MER Flight Vehicles.

  3. Critical swelling of fluctuating capsules

    NASA Astrophysics Data System (ADS)

    Diamant, Haim; Haleva, Emir

    2009-03-01

    In many natural transport processes the solute molecules to be transported are encapsulated in semipermeable, flexible membrane vesicles of micron size. We study the swelling of such fluctuating capsules, as the number of encapsulated particles is increased, or the concentration of the outer solution is decreased. The approach to the maximum volume-to-area ratio and the associated buildup of membrane tension involve a continuous phase transition and follow universal scaling laws. The criticality and its features are model-independent, arising solely from the interplay between volume and surface degrees of freedom.ootnotetextE. Haleva and H. Diamant, Phys. Rev. Lett. 101, 078104 (2008).

  4. Trapped translocation intermediates establish the route for export of capsular polysaccharides across Escherichia coli outer membranes.

    PubMed

    Nickerson, Nicholas N; Mainprize, Iain L; Hampton, Lauren; Jones, Michelle L; Naismith, James H; Whitfield, Chris

    2014-06-03

    The outer membrane (OM) of Gram-negative bacteria is designed to exclude potentially harmful molecules. This property presents a challenge for bacteria that must secrete proteins and large glycoconjugates to grow, divide, and persist. Proteins involved in trafficking such molecules have been identified, but their precise roles are often unresolved due to the difficulty in capturing "snapshots" during the export pathway. Wza is the prototype for the large family of OM polysaccharide export proteins. In Escherichia coli, Wza is essential for the assembly of a capsule, a protective surface coat composed of long-chain polysaccharides. Wza creates an octameric α-helical channel spanning the OM, but the bulk of the protein exists as a large periplasmic structure enclosing an extensive lumen. Residues within the lumen of Wza were targeted for site-specific incorporation of the UV photo-cross-linkable unnatural amino acid p-benzoyl-L-phenylalanine. Using this in vivo photo-cross-linking strategy, we were able to trap polysaccharide translocation intermediates within the lumen of Wza, providing the first unequivocal evidence to our knowledge that nascent capsular polysaccharide chains exit the cell through the Wza portal.

  5. Water-polysaccharide interactions in the primary cell wall of Arabidopsis thaliana from polarization transfer solid-state NMR.

    PubMed

    White, Paul B; Wang, Tuo; Park, Yong Bum; Cosgrove, Daniel J; Hong, Mei

    2014-07-23

    Polysaccharide-rich plant cell walls are hydrated under functional conditions, but the molecular interactions between water and polysaccharides in the wall have not been investigated. In this work, we employ polarization transfer solid-state NMR techniques to study the hydration of primary-wall polysaccharides of the model plant, Arabidopsis thaliana. By transferring water (1)H polarization to polysaccharides through distance- and mobility-dependent (1)H-(1)H dipolar couplings and detecting it through polysaccharide (13)C signals, we obtain information about water proximity to cellulose, hemicellulose, and pectins as well as water mobility. Both intact and partially extracted cell wall samples are studied. Our results show that water-pectin polarization transfer is much faster than water-cellulose polarization transfer in all samples, but the extent of extraction has a profound impact on the water-polysaccharide spin diffusion. Removal of calcium ions and the consequent extraction of homogalacturonan (HG) significantly slowed down spin diffusion, while further extraction of matrix polysaccharides restored the spin diffusion rate. These trends are observed in cell walls with similar water content, thus they reflect inherent differences in the mobility and spatial distribution of water. Combined with quantitative analysis of the polysaccharide contents, our results indicate that calcium ions and HG gelation increase the amount of bound water, which facilitates spin diffusion, while calcium removal disrupts the gel and gives rise to highly dynamic water, which slows down spin diffusion. The recovery of spin diffusion rates after more extensive extraction is attributed to increased water-exposed surface areas of the polysaccharides. Water-pectin spin diffusion precedes water-cellulose spin diffusion, lending support to the single-network model of plant primary walls in which a substantial fraction of the cellulose surface is surrounded by pectins.

  6. The Vi capsular polysaccharide enables Salmonella enterica serovar typhi to evade microbe-guided neutrophil chemotaxis.

    PubMed

    Wangdi, Tamding; Lee, Cheng-Yuk; Spees, Alanna M; Yu, Chenzhou; Kingsbury, Dawn D; Winter, Sebastian E; Hastey, Christine J; Wilson, R Paul; Heinrich, Volkmar; Bäumler, Andreas J

    2014-08-01

    Salmonella enterica serovar Typhi (S. Typhi) causes typhoid fever, a disseminated infection, while the closely related pathogen S. enterica serovar Typhimurium (S. Typhimurium) is associated with a localized gastroenteritis in humans. Here we investigated whether both pathogens differ in the chemotactic response they induce in neutrophils using a single-cell experimental approach. Surprisingly, neutrophils extended chemotactic pseudopodia toward Escherichia coli and S. Typhimurium, but not toward S. Typhi. Bacterial-guided chemotaxis was dependent on the presence of complement component 5a (C5a) and C5a receptor (C5aR). Deletion of S. Typhi capsule biosynthesis genes markedly enhanced the chemotactic response of neutrophils in vitro. Furthermore, deletion of capsule biosynthesis genes heightened the association of S. Typhi with neutrophils in vivo through a C5aR-dependent mechanism. Collectively, these data suggest that expression of the virulence-associated (Vi) capsular polysaccharide of S. Typhi obstructs bacterial-guided neutrophil chemotaxis.

  7. Initiation and Synthesis of the Streptococcus pneumoniae Type 3 Capsule on a Phosphatidylglycerol Membrane Anchor

    PubMed Central

    Cartee, Robert T.; Forsee, W. Thomas; Yother, Janet

    2005-01-01

    The type 3 synthase from Streptococcus pneumoniae is a processive β-glycosyltransferase that assembles the type 3 polysaccharide [3)-β-d-GlcUA-(1→4)-β-d-Glc-(1→] by a multicatalytic process. Polymer synthesis occurs via alternate additions of Glc and GlcUA onto the nonreducing end of the growing polysaccharide chain. In the presence of a single nucleotide sugar substrate, the type 3 synthase ejects its nascent polymer and also adds a single sugar onto a lipid acceptor. Following single sugar incorporation from either UDP-[14C]Glc or UDP-[14C]GlcUA, we found that phospholipase D digestion of the Glc-labeled lipid yielded a product larger than a monosaccharide, while digestion of the GlcUA-labeled lipid resulted in a product larger than a disaccharide. These data indicated that the lipid acceptor contained a headgroup and that the order of addition to the lipid acceptor was Glc followed by GlcUA. Higher-molecular-weight product synthesized in vitro was also sensitive to phospholipase D digestion, suggesting that the same lipid acceptor was being used for single sugar additions and for polymer formation. Mass spectral analysis of the anionic lipids of a type 3 S. pneumoniae strain demonstrated the presence of glycosylated phosphatidylglycerol. This lipid was also observed in Escherichia coli strains expressing the recombinant type 3 synthase. The presence of the lipid primer in S. pneumoniae membranes explained both the ability of the synthase to reinitiate polysaccharide synthesis following ejection of its nascent chain and the association of newly synthesized polymer with the membrane. Unlike most S. pneumoniae capsular polysaccharides, the type 3 capsule is not covalently linked to the cell wall. The present data indicate that phosphatidylglycerol may anchor the type 3 polysaccharide to the cell membrane. PMID:15968057

  8. Some ultrastructural information on intact, living bacterial cells and related cell-wall fragments as given by FTIR

    NASA Astrophysics Data System (ADS)

    Naumann, D.

    1984-05-01

    Living bacterial cells of Staphylococcus aureus have been measured from aqueous suspensions taking advantage of the solvent subtraction capabilities of FTIR. All spectral features, between 1800-800 cm -1, of the intact cells could be measured with a reproducibility of better than ±5% when applying strict metabolic control of cell growth and a highly standardized experimental procedure prior to IR measurements. IR bands near 1745, 1656, 1547, 1240 and 1200-1000 cm -1were tentatively assigned to: CO stretching of ester groups, amide I and amide II bands of the various peptides and proteins, asymmetric stretching of phosphate groups and complex vibrational modes resulting from polysaccharidal compounds, respectively. Absorbance subtraction of IR spectra of different intact baterial cells and cell-wall preparations yielded reasonable results on structural variations accompanying: (i) cell growth, (ii) use of different growth media, (iii) chemical treatment of cells and (iv) biochemical isolation processes of cell walls from the intact cells.

  9. The disintegration behaviour of capsules in fed subjects: a comparison of hypromellose (carrageenan) capsules and standard gelatin capsules.

    PubMed

    Jones, B E; Basit, A W; Tuleu, C

    2012-03-15

    Two-piece hard shell capsules made from hypromellose (or hydroxypropyl methylcellulose, HPMC) containing carrageenan as a gelling agent have been proposed as an alternative to conventional gelatin capsules for oral drug delivery. We have previously compared the disintegration of hypromellose(carrageenan) (Quali-V(®)) and gelatin capsules (Qualicaps) in fasted human subjects using the technique of gamma scintigraphy. This second study used the same technique with both fasted and fed human subjects. Size 0 capsules were filled with powder plugs made from lactose and did not contain croscarmellose as in the original study. The capsules were separately radiolabelled with indium-111 and technetium-99m. Both capsules were administered simultaneously with 180ml water to eight healthy male subjects following an overnight fast. Each volunteer was positioned in front of the gamma camera and sequential 60s images were acquired in a continuous manner for 30min. The mean (±S.D.) disintegration time in the fasted state for the hypromellose(carrageenan) capsules was 8±2min and for gelatin 7±3min. These results were not statistically different from the data in the original study and show that the removal of the croscarmellose had no effect on the results. The mean (±S.D.) disintegration time in the fed state for the hypromellose(carrageenan) capsules was 16±5min and for the gelatin capsules was 12±4min. There was no statistical difference between the hypromellose(carrageenan) and gelatin capsules in either the fed or fasted state.

  10. Biodegradable and redox-responsive chitosan/poly(L-aspartic acid) submicron capsules for transmucosal delivery of proteins and peptides.

    PubMed

    Zheng, C; Zhang, X G; Sun, L; Zhang, Z P; Li, C X

    2013-04-01

    The development of peptides and proteins is hampered by their rapid clearance in liver and other body tissues by proteolytic enzymes, so these drugs are difficult to administer except for the injection. Here, we designed and fabricated a novel biodegradable and redox-responsive submicron capsules through the layer-by-layer technique with poly(L-aspartic acid) and chitosan for transmucosal delivery of proteins and peptides. TEM graphs reveal that the intact submicron capsules were obtained and the shell of submicron capsules was about 40 nm. The mucoadhesion test indicates that the adsorption amount of the mucin could achieve up to 96.2 μg per 2 mg. The cell viability test shows that all types of submicron capsules had good cytocompatibility and the cell viability was above 90 %. As a drug model, the insulin could be loaded in the submicron capsules, and the loading efficiency was about 5 %. The release amount of insulin could be regulated by the levels of GSH. Therefore, the mucoadhesive submicron capsules as vehicles have a potential for the mucosal delivery (e.g. nasal and buccal) of therapeutic peptide and protein drugs.

  11. Cryptococcus gattii Capsule Blocks Surface Recognition Required for Dendritic Cell Maturation Independent of Internalization and Antigen Processing.

    PubMed

    Huston, Shaunna M; Ngamskulrungroj, Popchai; Xiang, Richard F; Ogbomo, Henry; Stack, Danuta; Li, Shu Shun; Timm-McCann, Martina; Kyei, Stephen K; Oykhman, Paul; Kwon-Chung, Kyung J; Mody, Christopher H

    2016-02-01

    Cryptococcus gattii is an emerging fungal pathogen on the west coast of Canada and the United States that causes a potentially fatal infection in otherwise healthy individuals. In previous investigations of the mechanisms by which C. gattii might subvert cell-mediated immunity, we found that C. gattii failed to induce dendritic cell (DC) maturation, leading to defective T cell responses. However, the virulence factor and the mechanisms of evasion of DC maturation remain unknown. The cryptococcal polysaccharide capsule is a leading candidate because of its antiphagocytic properties. Consequently, we asked if the capsule of C. gattii was involved in evasion of DC maturation. We constructed an acapsular strain of C. gattii through CAP59 gene deletion by homologous integration. Encapsulated C. gattii failed to induce human monocyte-derived DC maturation and T cell proliferation, whereas the acapsular mutant induced both processes. Surprisingly, encapsulation impaired DC maturation independent of its effect on phagocytosis. Indeed, DC maturation required extracellular receptor signaling that was dependent on TNF-α and p38 MAPK, but not ERK activation, and the cryptococcal capsule blocked this extracellular recognition. Although the capsule impaired phagocytosis that led to pH-dependent serine-, threonine-, and cysteine-sensitive protease-dependent Ag processing, it was insufficient to impair T cell responses. In summary, C. gattii affects two independent processes, leading to DC maturation and Ag processing. The polysaccharide capsule masked extracellular detection and reduced phagocytosis that was required for DC maturation and Ag processing, respectively. However, the T cell response was fully restored by inducing DC maturation.

  12. Transcriptional organization and regulation of the Escherichia coli K30 group 1 capsule biosynthesis (cps) gene cluster.

    PubMed

    Rahn, Andrea; Whitfield, Chris

    2003-02-01

    Escherichia coli group 1 capsules are important virulence determinants, yet little is known about the transcriptional organization or regulation of their biosynthetic (cps) operons. Transcription of the prototype serotype K30 cluster is modulated by the JUMPStart-RfaH antitermination mechanism, with the cps promoter being localized to a region immediately upstream of the JUMPStart sequence. A putative stem-loop structure located within the K30 cps cluster separates conserved genes with products that are required for surface expression of capsule from serotype-specific genes encoding enzymes for polymer repeat-unit synthesis and polymerization. This putative stem-loop structure significantly reduces transcription in a termination-probe vector and may contribute to differential expression of the cps genes. Previous work indicated that increased amounts of group 1 capsular polysaccharide synthesis resulted from the overexpression of the Rcs (regulator of capsule synthesis) proteins. However, neither overexpression of the transcriptional activator RcsB nor an rcsB::aadA chromosomal insertion altered the level of transcription measured by cps::lacZ fusions. In the group 1 strains examined, an RcsAB box was found immediately upstream of galF, a gene involved in the production of sugar nucleotide precursors. Overexpression of RcsB was found to result in a threefold increase in transcription of a galF::lacZ chromosomal fusion. Moreover, overexpression of GalF gave rise to a two- to threefold increase in cell-free as well as cell-associated capsule, without affecting cps::lacZ activity. These results indicate that transcription of the E. coli group 1 capsule cluster itself is not regulated by the Rcs system and may, in fact, be constitutive. However, the Rcs system can potentially influence levels of capsular polysaccharide production by increasing galF transcription and influencing the available pool of biosynthetic precursors.

  13. Structurally altered capsular polysaccharides produced by mutant bacteria

    NASA Technical Reports Server (NTRS)

    Kern, Roger G. (Inventor); Petersen, Gene R. (Inventor); Richards, Gil F. (Inventor)

    1995-01-01

    Structurally altered capsular polysaccharides are produced by mutant bacteria. These polysaccharides are isolated by selecting a wild type bacterial strain and a phage producing degradative enzymes that have substrate specificity for the capsular polysaccharides produced by the wild type bacteria. Phage-resistant mutants producing capsular polysaccharides are selected and the structurally altered capsular polysaccharide is isolated therefrom.

  14. Preparation of polyurea capsules using electrocapillary emulsification.

    PubMed

    Sakai, Hideki; Tanaka, Keisuke; Fukushima, Hiroshi; Tsuchiya, Koji; Sakai, Kenichi; Kondo, Tamotsu; Abe, Masahiko

    2008-10-15

    Polyurea capsules have been prepared using the electrocapillary emulsification method in order to control the particle size within the submicron range. The polyurea capsules have been synthesized via the interfacial polycondensation between tetraethylenepentamine (TEP) dissolved in an aqueous phase and toluenediisocyanate (TDI) dissolved in a mixture of cyclohexane and chloroform. The oil phase contains a lipophilic nonionic surfactant (sorbitan sesquioleate, SO-15) as an emulsion stabilizer. Scanning electron microscope (SEM) observations reveal that the capsule size is decreased as (i) the amount of the aqueous phase injected into the oil phase is decreased and (ii) the dropping rate of the aqueous phase is decreased. Indeed, the mole ratio of the two monomers makes a significant impact on the capsule size. Under the best experimental condition examined in this study, we obtained polyurea capsules with a diameter of approximately 200nm, which should be useful in developing bioreactors or carriers.

  15. Loss of Very-Long O-Antigen Chains Optimizes Capsule-Mediated Immune Evasion by Salmonella enterica Serovar Typhi

    PubMed Central

    Crawford, Robert W.; Wangdi, Tamding; Spees, Alanna M.; Xavier, Mariana N.; Tsolis, Renée M.; Bäumler, Andreas J.

    2013-01-01

    ABSTRACT Expression of capsular polysaccharides is a variable trait often associated with more-virulent forms of a bacterial species. For example, typhoid fever is caused by the capsulated Salmonella enterica serovar Typhi, while nontyphoidal Salmonella serovars associated with gastroenteritis are noncapsulated. Here we show that optimization of the immune evasive properties conferred by the virulence-associated (Vi) capsular polysaccharide involved an additional alteration to the cell envelope of S. Typhi, namely inactivation of the fepE gene, encoding the regulator of very-long O-antigen chains. Introduction of the capsule-encoding viaB locus into the nontyphoidal S. enterica serovar Typhimurium reduced complement deposition in vitro and intestinal inflammation in a mouse colitis model. However, both phenotypes were markedly enhanced when the viaB locus was introduced into an S. Typhimurium fepE mutant, which lacks very-long O-antigen chains. Collectively, these data suggest that during the evolution of the S. Typhi lineage, loss of very-long O-antigen chains by pseudogene formation was an adaptation to maximize the anti-inflammatory properties of the Vi capsular polysaccharide. PMID:23860765

  16. Thermoregulation of Capsule Production by Streptococcus pyogenes

    PubMed Central

    Kang, Song Ok; Wright, Jordan O.; Tesorero, Rafael A.; Lee, Hyunwoo; Beall, Bernard; Cho, Kyu Hong

    2012-01-01

    The capsule of Streptococcus pyogenes serves as an adhesin as well as an anti-phagocytic factor by binding to CD44 on keratinocytes of the pharyngeal mucosa and the skin, the main entry sites of the pathogen. We discovered that S. pyogenes HSC5 and MGAS315 strains are further thermoregulated for capsule production at a post-transcriptional level in addition to the transcriptional regulation by the CovRS two-component regulatory system. When the transcription of the hasABC capsular biosynthetic locus was de-repressed through mutation of the covRS system, the two strains, which have been used for pathogenesis studies in the laboratory, exhibited markedly increased capsule production at sub-body temperature. Employing transposon mutagenesis, we found that CvfA, a previously identified membrane-associated endoribonuclease, is required for the thermoregulation of capsule synthesis. The mutation of the cvfA gene conferred increased capsule production regardless of temperature. However, the amount of the capsule transcript was not changed by the mutation, indicating that a post-transcriptional regulator mediates between CvfA and thermoregulated capsule production. When we tested naturally occurring invasive mucoid strains, a high percentage (11/53, 21%) of the strains exhibited thermoregulated capsule production. As expected, the mucoid phenotype of these strains at sub-body temperature was due to mutations within the chromosomal covRS genes. Capsule thermoregulation that exhibits high capsule production at lower temperatures that occur on the skin or mucosal surface potentially confers better capability of adhesion and invasion when S. pyogenes penetrates the epithelial surface. PMID:22615992

  17. Thermoregulation of capsule production by Streptococcus pyogenes.

    PubMed

    Kang, Song Ok; Wright, Jordan O; Tesorero, Rafael A; Lee, Hyunwoo; Beall, Bernard; Cho, Kyu Hong

    2012-01-01

    The capsule of Streptococcus pyogenes serves as an adhesin as well as an anti-phagocytic factor by binding to CD44 on keratinocytes of the pharyngeal mucosa and the skin, the main entry sites of the pathogen. We discovered that S. pyogenes HSC5 and MGAS315 strains are further thermoregulated for capsule production at a post-transcriptional level in addition to the transcriptional regulation by the CovRS two-component regulatory system. When the transcription of the hasABC capsular biosynthetic locus was de-repressed through mutation of the covRS system, the two strains, which have been used for pathogenesis studies in the laboratory, exhibited markedly increased capsule production at sub-body temperature. Employing transposon mutagenesis, we found that CvfA, a previously identified membrane-associated endoribonuclease, is required for the thermoregulation of capsule synthesis. The mutation of the cvfA gene conferred increased capsule production regardless of temperature. However, the amount of the capsule transcript was not changed by the mutation, indicating that a post-transcriptional regulator mediates between CvfA and thermoregulated capsule production. When we tested naturally occurring invasive mucoid strains, a high percentage (11/53, 21%) of the strains exhibited thermoregulated capsule production. As expected, the mucoid phenotype of these strains at sub-body temperature was due to mutations within the chromosomal covRS genes. Capsule thermoregulation that exhibits high capsule production at lower temperatures that occur on the skin or mucosal surface potentially confers better capability of adhesion and invasion when S. pyogenes penetrates the epithelial surface.

  18. Marine Polysaccharides in Pharmaceutical Applications: An Overview

    PubMed Central

    Laurienzo, Paola

    2010-01-01

    The enormous variety of polysaccharides that can be extracted from marine plants and animal organisms or produced by marine bacteria means that the field of marine polysaccharides is constantly evolving. Recent advances in biological techniques allow high levels of polysaccharides of interest to be produced in vitro. Biotechnology is a powerful tool to obtain polysaccharides from a variety of micro-organisms, by controlling the growth conditions in a bioreactor while tailoring the production of biologically active compounds. Following an overview of the current knowledge on marine polysaccharides, with special attention to potential pharmaceutical applications and to more recent progress on the discovering of new polysaccharides with biological appealing characteristics, this review will focus on possible strategies for chemical or physical modification aimed to tailor the final properties of interest. PMID:20948899

  19. Hydrodynamick instabilities on ICF capsules

    SciTech Connect

    Haan, S.W.

    1991-06-07

    This article summarizes our current understanding of hydrodynamic instabilities as relevant to ICF. First we discuss classical, single mode Rayleigh-Taylor instability, and nonlinear effects in the evolution of a single mode. Then we discuss multimode systems, considering: (1) the onset of nonlinearity; (2) a second order mode coupling theory for weakly nonlinear effects, and (3) the fully nonlinear regime. Two stabilization mechanisms relevant to ICF are described next: gradient scale length and convective stabilization. Then we describe a model which is meant to estimate the weakly nonlinear evolution of multi-mode systems as relevant to ICF, given the short-wavelength stabilization. Finally, we discuss the relevant code simulation capability, and experiments. At this time we are quite optimistic about our ability to estimate instability growth on ICF capsules, but further experiments and simulations are needed to verify the modeling. 52 refs.

  20. Unique lipid anchor attaches Vi antigen capsule to the surface of Salmonella enterica serovar Typhi

    PubMed Central

    Liston, Sean D.; Ovchinnikova, Olga G.

    2016-01-01

    Polysaccharide capsules are surface structures that are critical for the virulence of many Gram-negative pathogenic bacteria. Salmonella enterica serovar Typhi is the etiological agent of typhoid fever. It produces a capsular polysaccharide known as “Vi antigen,” which is composed of nonstoichiometrically O-acetylated α-1,4-linked N-acetylgalactosaminuronic acid residues. This glycan is a component of currently available vaccines. The genetic locus for Vi antigen production is also present in soil bacteria belonging to the genus Achromobacter. Vi antigen assembly follows a widespread general strategy with a characteristic glycan export step involving an ATP-binding cassette transporter. However, Vi antigen producers lack the enzymes that build the conserved terminal glycolipid characterizing other capsules using this method. Achromobacter species possess a Vi antigen-specific depolymerase enzyme missing in S. enterica Typhi, and we exploited this enzyme to isolate acylated Vi antigen termini. Mass spectrometry analysis revealed a reducing terminal N-acetylhexosamine residue modified with two β-hydroxyl acyl chains. This terminal structure resembles one half of lipid A, the hydrophobic portion of bacterial lipopolysaccharides. The VexE protein encoded in the Vi antigen biosynthesis locus shares similarity with LpxL, an acyltransferase from lipid A biosynthesis. In the absence of VexE, Vi antigen is produced, but its physical properties are altered, its export is impaired, and a Vi capsule structure is not assembled on the cell surface. The structure of the lipidated terminus dictates a unique assembly mechanism and has potential implications in pathogenesis and vaccine production. PMID:27226298

  1. Unique lipid anchor attaches Vi antigen capsule to the surface of Salmonella enterica serovar Typhi.

    PubMed

    Liston, Sean D; Ovchinnikova, Olga G; Whitfield, Chris

    2016-06-14

    Polysaccharide capsules are surface structures that are critical for the virulence of many Gram-negative pathogenic bacteria. Salmonella enterica serovar Typhi is the etiological agent of typhoid fever. It produces a capsular polysaccharide known as "Vi antigen," which is composed of nonstoichiometrically O-acetylated α-1,4-linked N-acetylgalactosaminuronic acid residues. This glycan is a component of currently available vaccines. The genetic locus for Vi antigen production is also present in soil bacteria belonging to the genus Achromobacter Vi antigen assembly follows a widespread general strategy with a characteristic glycan export step involving an ATP-binding cassette transporter. However, Vi antigen producers lack the enzymes that build the conserved terminal glycolipid characterizing other capsules using this method. Achromobacter species possess a Vi antigen-specific depolymerase enzyme missing in S enterica Typhi, and we exploited this enzyme to isolate acylated Vi antigen termini. Mass spectrometry analysis revealed a reducing terminal N-acetylhexosamine residue modified with two β-hydroxyl acyl chains. This terminal structure resembles one half of lipid A, the hydrophobic portion of bacterial lipopolysaccharides. The VexE protein encoded in the Vi antigen biosynthesis locus shares similarity with LpxL, an acyltransferase from lipid A biosynthesis. In the absence of VexE, Vi antigen is produced, but its physical properties are altered, its export is impaired, and a Vi capsule structure is not assembled on the cell surface. The structure of the lipidated terminus dictates a unique assembly mechanism and has potential implications in pathogenesis and vaccine production.

  2. Polysaccharide-based nanocomposites and their applications

    PubMed Central

    Zheng, Yingying; Monty, Jonathan; Linhardt, Robert J.

    2014-01-01

    Polysaccharide nanocomposites have become increasingly important materials over the past decade. Polysaccharides offer a green alternative to synthetic polymers in the preparation of soft nanomaterials. They have also been used in composites with hard nanomaterials, such as metal nanoparticles and carbon-based nanomaterials. This mini review describes methods for polysaccharide nanocomposite preparation and reviews the various types and diverse applications for these novel materials. PMID:25498200

  3. Biosynthesis and assembly of cell wall polysaccharides in cereal grasses

    SciTech Connect

    Carpita, N.C.

    1991-04-01

    We have just completed the second year of a three-year project entitled Biosynthesis assembly of cell wall polysaccharides in cereal grasses.'' We made significant progress on two aspects of cell wall synthesis in grasses and greatly refined gas-liquid and high- performance liquid chromatographic techniques necessary to identify the products of synthesis in vitro and in vivo. First, Dr. David Gibeaut, a post-doctoral associate, devised a convenient procedure for the enrichment of Golgi membranes by flotation centrifugation following initial downward rate-zonal separation. Based on comparison of the IDPase marker enzyme, flotation centrifugation enriched the Golgi apparatus almost 7-fold after the initial downward separation. This system is now used in our studies of the synthesis in vitro of the mixed-linkage {beta}-D-glucan. Second, Gibeaut and I have devised a simple technique to feed radioactive sugars into intact growing seedlings and follow incorporation of radioactivity into and turnover from specific cell wall polysaccharides. The project has also provided a few spin-off projects that have been productive as well. First, in collaboration with the group of Prof. Peter Kaufman, University of Michigan, we examined changes in cell wall structure concomitant with reaction to gravistimulation in the gravisensing oat pulvinus. Second, Dr. Gibeaut developed a simple clean-up procedure for partially methylated alditol derivatives to remove a large amount of undesirable interfering compounds that confound separation of the derivatives by gas-liquid chromatography. 5 refs.

  4. Exploding a myth: the capsule dehiscence mechanism and the function of pseudostomata in Sphagnum.

    PubMed

    Duckett, Jeffrey G; Pressel, Silvia; P'ng, Ken M Y; Renzaglia, Karen S

    2009-01-01

    The nineteenth century air-gun explanation for explosive spore discharge in Sphagnum has never been tested experimentally. Similarly, the function of the numerous stomata ubiquitous in the capsule walls has never been investigated. Both intact and pricked Sphagnum capsules, that were allowed to dry out, all dehisced over an 8-12 h period during which time the stomatal guard cells gradually collapsed and their potassium content, measured by X-ray microanalysis in a cryoscanning electron microscope, gradually increased. By contrast, guard cell potassium fell in water-stressed Arabidopsis. The pricking experiments demonstrate that the air-gun notion for explosive spore discharge in Sphagnum is inaccurate; differential shrinkage of the capsule walls causes popping off the rigid operculum. The absence of evidence for a potassium-regulating mechanism in the stomatal guard cells and their gradual collapse before spore discharge indicates that their sole role is facilitation of sporophyte desiccation that ultimately leads to capsule dehiscence. Our novel functional data on Sphagnum, when considered in relation to bryophyte phylogeny, suggest the possibility that stomata first appeared in land plants as structures that facilitated sporophyte drying out before spore discharge and only subsequently acquired their role in the regulation of gaseous exchange.

  5. Advances on Bioactive Polysaccharides from Medicinal Plants.

    PubMed

    Xie, Jian-Hua; Jin, Ming-Liang; Morris, Gordon A; Zha, Xue-Qiang; Chen, Han-Qing; Yi, Yang; Li, Jing-En; Wang, Zhi-Jun; Gao, Jie; Nie, Shao-Ping; Shang, Peng; Xie, Ming-Yong

    2016-07-29

    In recent decades, the polysaccharides from the medicinal plants have attracted a lot of attention due to their significant bioactivities, such as anti-tumor activity, antioxidant activity, anticoagulant activity, antidiabetic activity, radioprotection effect, anti-viral activity, hypolipidemic and immunomodulatory activities, which make them suitable for medicinal applications. Previous studies have also shown that medicinal plant polysaccharides are non-toxic and show no side effects. Based on these encouraging observations, most researches have been focusing on the isolation and identification of polysaccharides, as well as their bioactivities. A large number of bioactive polysaccharides with different structural features and biological effects from medicinal plants have been purified and characterized. This review provides a comprehensive summary of the most recent developments in physiochemical, structural features and biological activities of bioactive polysaccharides from a number of important medicinal plants, such as polysaccharides from Astragalus membranaceus, Dendrobium plants, Bupleurum, Cactus fruits, Acanthopanax senticosus, Angelica sinensis (Oliv.) Diels, Aloe barbadensis Miller, and Dimocarpus longan Lour. Moreover, the paper has also been focused on the applications of bioactive polysaccharides for medicinal applications. Recent studies have provided evidence that polysaccharides from medicinal plants can play a vital role in bioactivities. The contents and data will serve as a useful reference material for further investigation, production, and application of these polysaccharides in functional foods and therapeutic agents.

  6. Lightweight, highly compressible, noncrystalline cellulose capsules.

    PubMed

    Carrick, Christopher; Lindström, Stefan B; Larsson, Per Tomas; Wågberg, Lars

    2014-07-08

    We demonstrate how to prepare extraordinarily deformable, gas-filled, spherical capsules from nonmodified cellulose. These capsules have a low nominal density, ranging from 7.6 to 14.2 kg/m(3), and can be deformed elastically to 70% deformation at 50% relative humidity. No compressive strain-at-break could be detected for these dry cellulose capsules, since they did not rupture even when compressed into a disk with pockets of highly compressed air. A quantitative constitutive model for the large deformation compression of these capsules is derived, including their high-frequency mechanical response and their low-frequency force relaxation, where the latter is governed by the gas barrier properties of the dry capsule. Mechanical testing corroborated these models with good accuracy. Force relaxation measurements at a constant compression rendered an estimate for the gas permeability of air through the capsule wall, calculated to 0.4 mL μm/m(2) days kPa at 50% relative humidity. These properties taken together open up a large application area for the capsules, and they could most likely be used for applications in compressible, lightweight materials and also constitute excellent model materials for adsorption and adhesion studies.

  7. [Evaluation of nopal capsules in diabetes mellitus].

    PubMed

    Frati Munari, A C; Vera Lastra, O; Ariza Andraca, C R

    1992-01-01

    To find out if commercial capsules with dried nopal (prickle-pear cactus, Opuntia ficus indica may have a role in the management of diabetes mellitus, three experiments were performed: 30 capsules where given in fasting condition to 10 diabetic subjects and serum glucose was measured through out 3 hours; a control test was performed with 30 placebo capsules. OGTT with previous intake of 30 nopal or placebo capsules was performed in ten healthy individuals. In a crossover and single blinded study 14 diabetic patients withdrew the oral hypoglycemic treatment and received 10 nopal or placebo capsules t.i.d. during one week; serum glucose, cholesterol and tryglycerides levels were measured before and after each one-week period. Five healthy subjects were also studied in the same fashion. Opuntia capsules did not show acute hypoglycemic effect and did not influence OGTT. In diabetic patients serum glucose, cholesterol and tryglycerides levels did not change with Opuntia, but they increased with placebo (P < 0.01 glucose and cholesterol, P = NS triglycerides). In healthy individuals glycemia did not change with nopal, while cholesterol and triglycerides decreased (P < 0.01 vs. placebo). The intake of 30 Opuntia capsules daily in patients with diabetes mellitus had a discrete beneficial effect on glucose and cholesterol. However this dose is unpractical and at present it is not recommended in the management of diabetes mellitus.

  8. Isolation, Characterization, and Localization of a Capsule-Associated Gene, CAP10, of Cryptococcus neoformans

    PubMed Central

    Chang, Y. C.; Kwon-Chung, K. J.

    1999-01-01

    Cryptococcus neoformans is a pathogenic fungus which most commonly affects the central nervous system and causes fatal meningoencephalitis primarily in patients with AIDS. This fungus produces a thick extracellular polysaccharide capsule which is well recognized as a virulence factor. Here, we describe the isolation and characterization of a novel gene, CAP10, which is required for capsule formation. Complementation of the acapsular cap10 mutant produced an encapsulated strain and the deletion of CAP10 from a wild strain resulted in an acapsular phenotype. The molecular mass of the hemagglutinin epitope-tagged Cap10p is about 73 kDa, which is similar to the size predicted from sequence analysis. When CAP10 was fused with a hybrid green fluorescent protein construct, the fluorescence signals appeared as patches in the cytoplasm. Using a reporter gene construct, we found that CAP10 was expressed at high levels in late-stationary-phase cells. In addition, we found that the expression levels of CAP10 are modulated by the transcriptional factor STE12α. Deletion of STE12α downregulated the expression levels of CAP10 while overexpression of STE12α upregulated the expression levels of CAP10. Animal model studies indicate that deletion of the CAP10 gene results in the loss of virulence, and complementation of the acapsular phenotype of cap10 restores virulence. Thus, CAP10 is required for capsule formation and virulence. PMID:10482503

  9. Oxygen fugacity and piston cylinder capsule assemblies

    NASA Astrophysics Data System (ADS)

    Jakobsson, S.

    2011-12-01

    A double capsule assembly designed to control oxygen fugacity in piston cylinder experiments has been tested at 1200 °C and 10 kbar. The assembly consists of an outer Pt-capsule containing a solid buffer (Ni-NiO or Co-CoO plus H2O) and an inner AuPd-capsule containing the sample, H2O and a Pt-wire. To prevent direct contact with the buffer phases the AuPd-capsule is embedded in finely ground Al2O3 along with some coarser, fractured Al2O3 facilitating fluid inclusion formation. No water loss is observed in the sample even after 48 hrs but a slight increase in water content is observed in longer duration runs due to oxygen and hydrogen diffusion into the AuPd-capsule. Carbon from the furnace also diffuses through the outer Pt-capsule but reacts with H2O in the outer capsule to form CO2 and never reaches the inner capsule. Oxygen fugacity of runs in equilibrium with the Ni-NiO and Co-CoO buffers was measured by analyzing the Fe content of the Pt-wire in the sample1 and by analyzing Fe dissolved in the AuPd capsule2. The second method gives values that are in good agreement with established buffer whereas results from the first method are one half to one log units higher than the established values. References 1. E. Medard, C. A. McCammon, J. A. Barr, T. L. Grove, Am. Mineral. 93, 1838 (2008). 2. J. Barr, T. Grove, Contrib. Mineral. Petrol. 160, 631 (2010)

  10. Asymmetric membrane osmotic capsules for terbutaline sulphate.

    PubMed

    Gobade, N G; Koland, Marina; Harish, K H

    2012-01-01

    The aim of the present study was to design an asymmetric membrane capsule, an osmotic pump-based drug delivery system of ethyl cellulose for controlled release of terbutaline sulphate. asymmetric membrane capsules contains pore-forming water soluble additive, sorbitol in different concentrations in the capsule shell membrane, which after coming in contact with water, dissolves, resulting in an in situ formation of a microporous structure. The terbutaline sulphate is a β-adrenoreceptor agonist widely used in the treatment of asthma. The oral dosage regimen of terbutaline sulphate is 5 mg twice or thrice daily, the plasma half-life is approximate 3-4 h and it produces GI irritation with extensive first pass metabolism. Hence, terbutaline sulphate was chosen as a model drug with an aim to develop controlled release system. Different formulations of ethyl cellulose were prepared by phase inversion technique using different concentrations of sorbitol as pore forming agent. It was found that the thickness of the prepared asymmetric membrane capsules was increased with increase in concentration of ethyl cellulose and pore forming agent, i.e. sorbitol. The dye release study in water and 10% sodium chloride solution indicates that, the asymmetric membrane capsules follow osmotic principle to release content. The pores formed due to sorbitol were confirmed by microscopic observation of transverse section of capsule membrane. Data of in vitro release study of terbutaline sulphate from asymmetric membrane capsules indicated that, the capsules prepared with 10% and 12.5% of ethyl cellulose and 25% of sorbitol released as much as 97.44% and 76.27% in 12 h, respectively with zero order release rate. Hence asymmetric membrane capsule of 10% ethyl cellulose and 25% of sorbitol is considered as optimum for controlled oral delivery of terbutaline sulphate.

  11. Asymmetric Membrane Osmotic Capsules for Terbutaline Sulphate

    PubMed Central

    Gobade, N. G.; Koland, Marina; Harish, K. H.

    2012-01-01

    The aim of the present study was to design an asymmetric membrane capsule, an osmotic pump-based drug delivery system of ethyl cellulose for controlled release of terbutaline sulphate. asymmetric membrane capsules contains pore-forming water soluble additive, sorbitol in different concentrations in the capsule shell membrane, which after coming in contact with water, dissolves, resulting in an in situ formation of a microporous structure. The terbutaline sulphate is a β-adrenoreceptor agonist widely used in the treatment of asthma. The oral dosage regimen of terbutaline sulphate is 5 mg twice or thrice daily, the plasma half-life is approximate 3-4 h and it produces GI irritation with extensive first pass metabolism. Hence, terbutaline sulphate was chosen as a model drug with an aim to develop controlled release system. Different formulations of ethyl cellulose were prepared by phase inversion technique using different concentrations of sorbitol as pore forming agent. It was found that the thickness of the prepared asymmetric membrane capsules was increased with increase in concentration of ethyl cellulose and pore forming agent, i.e. sorbitol. The dye release study in water and 10% sodium chloride solution indicates that, the asymmetric membrane capsules follow osmotic principle to release content. The pores formed due to sorbitol were confirmed by microscopic observation of transverse section of capsule membrane. Data of in vitro release study of terbutaline sulphate from asymmetric membrane capsules indicated that, the capsules prepared with 10% and 12.5% of ethyl cellulose and 25% of sorbitol released as much as 97.44% and 76.27% in 12 h, respectively with zero order release rate. Hence asymmetric membrane capsule of 10% ethyl cellulose and 25% of sorbitol is considered as optimum for controlled oral delivery of terbutaline sulphate. PMID:23204625

  12. Cell wall polysaccharide biosynthesis by membrane fragments from Streptococcus pyogenes and stabilized L-form.

    PubMed

    Cohen, M; Panos, C

    1971-05-01

    The formation and composition of a cell wall rhamnose-containing polysaccharide by membrane fragments from Streptococcus pyogenes and its stabilized L-form were compared. Also, the effect of prior treatment on the ability of coccal whole-cell and membrane fragments to incorporate radioactivity from thymidine diphosphate-(14)C-rhamnose, and the results of subsequent attempts to remove labeled polysaccharide from such membranes are given. L-form membrane fragments were capable of only 10% uptake of (14)C-rhamnose from this nucleotide as compared with streptococcal membranes. However, once bound, both membrane fragments polymerized rhamnose to the same extent. These findings tend to negate the almost complete lack of polymeric rhamnose within the intact L-form as being due to the absence of membrane enzymes necessary for the transfer of rhamnose from a suitable precursor to membrane acceptor sites or enzymes responsible for rhamnose polymerization. Degradation of labeled rhamnose polysaccharide after isolation from coccal membranes by mild acid hydrolysis showed muramic acid and glucosamine to be attached. This same polysaccharide from L-form membrane fragments was devoid of amino sugars. These data suggest the possible involvement of amino sugars in the attachment of cell wall polymeric rhamnose to the streptococcal cytoplasmic membrane. The absence of attached amino sugars to rhamnose polysaccharide from L-form membrane fragments is discussed in terms of this organism's continued inability for new cell wall formation. The isolation, from streptococcal membrane fragments, of a polysaccharide containing rhamnose and amino sugars common to at least two different streptococcal cell wall-type polymers was demonstrated.

  13. Fabrication of capsule assemblies, phase 3

    NASA Technical Reports Server (NTRS)

    Keeton, A. R.; Stemann, L. G.

    1973-01-01

    Thirteen capsule assemblies were fabricated for evaluation of fuel pin design concepts for a fast spectrum lithium cooled compact space power reactor. These instrumented assemblies were designed for real time test of prototype fuel pins. Uranium mononitride fuel pins were encased in AISI 304L stainless steel capsules. Fabrication procedures were fully qualified by process development and assembly qualification tests. Instrumentation reliability was achieved utilizing specially processed and closely controlled thermocouple hot zone fabrication and by thermal screening tests. Overall capsule reliability was achieved with an all electron beam welded assembly.

  14. Tag gas capsule with magnetic piercing device

    DOEpatents

    Nelson, Ira V.

    1976-06-22

    An apparatus for introducing a tag (i.e., identifying) gas into a tubular nuclear fuel element. A sealed capsule containing the tag gas is placed in the plenum in the fuel tube between the fuel and the end cap. A ferromagnetic punch having a penetrating point is slidably mounted in the plenum. By external electro-magnets, the punch may be caused to penetrate a thin rupturable end wall of the capsule and release the tag gas into the fuel element. Preferably the punch is slidably mounted within the capsule, which is in turn loaded as a sealed unit into the fuel element.

  15. Effect of orally administered polysaccharide from kefir grain on delayed-type hypersensitivity and tumor growth in mice.

    PubMed

    Murofushi, M; Shiomi, M; Aibara, K

    1983-02-01

    The effect of oral administration of a polysaccharide (KGF-C), isolated from the kefir grain, on delayed-type hypersensitivity (DTH) induced by picryl chloride and on the growth of solid tumor was examined in mice. KGF-C caused an increase in DTH response in intact mice and also tumor-bearing mice. The growth of tumor inoculated after the DTH test was markedly inhibited in the groups with high DTH response. A significant correlation between the DTH response and the antitumor activity was observed in intact mice.

  16. Selective synthesis and labeling of the polysialic acid capsule in Escherichia coli K1 strains with mutations in nanA and neuB.

    PubMed Central

    Vimr, E R

    1992-01-01

    The enzymes required for polysialic acid capsule synthesis in Escherichia coli K1 are encoded by region 2 neu genes of the multigenic kps cluster. To facilitate analysis of capsule synthesis and translocation, an E. coli K1 strain with mutations in nanA and neuB, affecting sialic acid degradation and synthesis, respectively, was constructed by transduction. The acapsular phenotype of the mutant was corrected in vivo by exogenous addition of sialic acid. By blocking sialic acid degradation, the nanA mutation allows intracellular metabolite accumulation, while the neuB mutation prevents dilution by the endogenous sialic acid pool and allows capsule synthesis to be controlled experimentally by the exogenous addition of sialic acid to the growth medium. Complementation was detected by bacteriophage K1F adsorption or infectivity assays. Polysialic acid translocation was observed within 2 min after addition of sialic acid to the growth medium, demonstrating the rapidity in vivo of sialic acid transport, activation, and polymerization and translocation of polysaccharide to the cell surface. Phage adsorption was not inhibited by chloramphenicol, demonstrating that de novo protein synthesis was not required for polysialic acid synthesis or translocation at 37 degrees C. Exogenous radiolabeled sialic acid was incorporated exclusively into capsular polysaccharide. The polymeric nature of the labeled capsular material was confirmed by gel permeation chromatography and susceptibility of sialyl polymers to K1F endo-N-acylneuraminidase. The ability to experimentally manipulate capsule expression provides new approaches for investigating polysialic acid synthesis and membrane translocation mechanisms. PMID:1400168

  17. Calorie restriction and susceptibility to intact pathogens

    PubMed Central

    2008-01-01

    Long-term calorie restriction (CR) causes numerous physiological changes that ultimately increase mean and maximum lifespan of most species examined to date. One physiological change that occurs with CR is enhanced immune function, as tested using antigens and mitogens to stimulate an immune response. Fewer studies have used intact pathogen exposure to test whether the enhanced capacity of the immune response during CR actually decreases susceptibility of hosts to their pathogens. So far, studies using intact bacteria, virus, and helminth worm exposure indicate that, despite similar or enhanced immune system function, CR hosts are more susceptible to infection by intact pathogens than their fully fed counterparts. Long-term CR studies that examine susceptibility to a variety of parasite taxa will help determine if direct CR or CR mimetics will be beneficial to people living in pathogen-rich environments. PMID:19424864

  18. Required Be Capsule Strength For Room Temperature Transport

    SciTech Connect

    Cook, B

    2005-03-21

    The purpose of this memo is to lay out the criteria for the Be capsule strength necessary for room temperature transport. Ultimately we will test full thickness capsules by sealing high pressures inside, but currently we are limited to both thinner capsules and alternative measures of capsule material strength.

  19. 21 CFR 520.2100 - Selenium, vitamin E capsules.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... E capsules. (a) Specifications. The capsules contain 2.19 milligrams of sodium selenite (equivalent... succinate) or 0.548 milligram of sodium selenite (equivalent to .25 milligram of selenium and 14 milligrams... capsule per 20 pounds of body weight to a maximum of 5 capsules with the dosage repeated at 3 day...

  20. 21 CFR 520.2100 - Selenium, vitamin E capsules.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... E capsules. (a) Specifications. The capsules contain 2.19 milligrams of sodium selenite (equivalent... succinate) or 0.548 milligram of sodium selenite (equivalent to .25 milligram of selenium and 14 milligrams... capsule per 20 pounds of body weight to a maximum of 5 capsules with the dosage repeated at 3 day...

  1. Does magnetically assisted capsule endoscopy improve small bowel capsule endoscopy completion rate? A randomised controlled trial

    PubMed Central

    Hale, Melissa F.; Drew, Kaye; Sidhu, Reena; McAlindon, Mark E.

    2016-01-01

    Background and study aims: Delayed gastric emptying is a significant factor in incomplete small bowel capsule examinations. Gastric transit could be hastened by external magnetic control of the capsule. We studied the feasibility of this approach to improve capsule endoscopy completion rates. Patients and methods: Prospective, single-center, randomized controlled trial involving 122 patients attending for small bowel capsule endoscopy using MiroCam Navi. Patients were randomized to either the control group (mobilisation for 30 minutes after capsule ingestion, followed by intramuscular metoclopramide 10 mg if the capsule failed to enter the small bowel) or the intervention group (1000 mL of water prior to capsule ingestion, followed by positional change and magnetic steering). Outcome measures were capsule endoscopy completion rate, gastric clarity and distention, relationship of body habitus to capsule endoscopy completion rate (CECR), and patient comfort scores. Results: 122 patients were recruited (61 each to the control and intervention groups: mean age 49 years [range 21 – 85], 61 females). There was no significant difference in CECR between the two groups (P = 0.39). Time to first pyloric image was significantly shorter in the intervention group (P = 0.03) but there was no difference in gastric transit times (P = 0.12), suggesting that magnetic control hastens capsular transit to the gastric antrum but does not influence duodenal passage. Gastric clarity and distention were significantly better in the intervention group (P < 0.0001 and P < 0.0001 respectively). Conclusions: Magnetic steering of a small bowel capsule is unable to overcome pyloric contractions to enhance gastric emptying and improve capsule endoscope completion rate. Excellent mucosal visualisation within the gastric cavity suggests this technique could be harnessed for capsule examination of the stomach. PMID:26878053

  2. Autism Spectrum Disorder and intact executive functioning.

    PubMed

    Ferrara, R; Ansermet, F; Massoni, F; Petrone, L; Onofri, E; Ricci, P; Archer, T; Ricci, S

    2016-01-01

    Earliest notions concerning autism (Autism Spectrum Disorders, ASD) describe the disturbance in executive functioning. Despite altered definition, executive functioning, expressed as higher cognitive skills required complex behaviors linked to the prefrontal cortex, are defective in autism. Specific difficulties in children presenting autism or verbal disabilities at executive functioning levels have been identified. Nevertheless, the developmental deficit of executive functioning in autism is highly diversified with huge individual variation and may even be absent. The aim of the present study to examine the current standing of intact executive functioning intact in ASD.

  3. Sample Return Capsule Landing (Artist's Concept)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Artist's rendering of the Stardust capsule's return to Earth. The Stardust spacecraft will bring back samples of interstellar dust, including recently discovered dust streaming into our Solar System from the direction of Sagittarius.

  4. Sample Return Capsule Landing Artist Concept

    NASA Image and Video Library

    2005-11-03

    Artist rendering of NASA Stardust capsule returning to Earth. The Stardust spacecraft will bring back samples of interstellar dust, including recently discovered dust streaming into our Solar System from the direction of Sagittarius.

  5. Multidimensional solid-state NMR studies of the structure and dynamics of pectic polysaccharides in uniformly 13C-labeled Arabidopsis primary cell walls

    SciTech Connect

    Dick-Perez, Marilu; Wang, Tuo; Salazar, Andre; Zabotina, Olga A.; Hong, Mei

    2012-07-08

    Plant cell wall (CW) polysaccharides are responsible for the mechanical strength and growth of plant cells; however, the high-resolution structure and dynamics of the CW polysaccharides are still poorly understood because of the insoluble nature of these molecules. Here, we use 2D and 3D magic-angle-spinning (MAS) solid-state NMR (SSNMR) to investigate the structural role of pectins in the plant CW. Intact and partially depectinated primary CWs of Arabidopsis thaliana were uniformly labeled with 13C and their NMR spectra were compared. Recent 13C resonance assignment of the major polysaccharides in Arabidopsis thaliana CWs allowed us to determine the effects of depectination on the intermolecular packing and dynamics of the remaining wall polysaccharides. 2D and 3D correlation spectra show the suppression of pectin signals, confirming partial pectin removal by chelating agents and sodium carbonate. Importantly, higher cross peaks are observed in 2D and 3D 13C spectra of the depectinated CW, suggesting higher rigidity and denser packing of the remaining wall polysaccharides compared with the intact CW. 13C spin–lattice relaxation times and 1H rotating-frame spin–lattice relaxation times indicate that the polysaccharides are more rigid on both the nanosecond and microsecond timescales in the depectinated CW. Taken together, these results indicate that pectic polysaccharides are highly dynamic and endow the polysaccharide network of the primary CW with mobility and flexibility, which may be important for pectin functions. This study demonstrates the capability of multidimensional SSNMR to determine the intermolecular interactions and dynamic structures of complex plant materials under near-native conditions. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Identification and characterization of a DNA region involved in the export of capsular polysaccharide by Actinobacillus pleuropneumoniae serotype 5a.

    PubMed Central

    Ward, C K; Inzana, T J

    1997-01-01

    Actinobacillus pleuropneumoniae synthesizes a serotype-specific capsular polysaccharide that acts as a protective barrier to phagocytosis and complement-mediated killing. To begin understanding the role of A. pleuropneumoniae capsule in virulence, we sought to identify the genes involved in capsular polysaccharide export and biosynthesis. A 5.3-kb XbaI fragment of A. pleuropneumoniae serotype 5a J45 genomic DNA that hybridized with DNA probes specific for the Haemophilus influenzae type b cap export region was cloned and sequenced. This A. pleuropneumoniae DNA fragment encoded four open reading frames, designated cpxDCBA. The nucleotide and predicted amino acid sequences of cpxDCBA contained a high degree of homology to the capsule export genes of H. influenzae type b bexDCBA, Neisseria meningitidis group B ctrABCD, and, to a lesser extent, Escherichia coli K1 and K5 kpsE and kpsMT. When present in trans, the cpxDCBA gene cluster complemented kpsM::TnphoA or kpsT::TnphoA mutations, determined by enzyme immunoassay and by restored sensitivity to a K5-specific bacteriophage. A cpxCB probe hybridized to genomic DNA from all A. pleuropneumoniae serotypes tested, indicating that this DNA was conserved among serotypes. These data suggest that A. pleuropneumoniae produces a group II family capsule similar to those of related mucosal pathogens. PMID:9169799

  7. A Unique Capsule Locus in the Newly Designated Actinobacillus pleuropneumoniae Serovar 16 and Development of a Diagnostic PCR Assay

    PubMed Central

    Li, Yanwen; Sárközi, Rita; Gottschalk, Marcelo; Angen, Øystein; Nedbalcova, Katerina; Rycroft, Andrew N.; Fodor, László

    2017-01-01

    ABSTRACT Actinobacillus pleuropneumoniae causes pleuropneumonia, an economically significant lung disease of pigs. Recently, isolates of A. pleuropneumoniae that were serologically distinct from the previously characterized 15 serovars were described, and a proposal was put forward that they comprised a new serovar, serovar 16. Here we used whole-genome sequencing of the proposed serovar 16 reference strain A-85/14 to confirm the presence of a unique capsular polysaccharide biosynthetic locus. For molecular diagnostics, primers were designed from the capsule locus of strain A-85/14, and a PCR was formulated that differentiated serovar 16 isolates from all 15 known serovars and other common respiratory pathogenic/commensal bacteria of pigs. Analysis of the capsule locus of strain A-85/14 combined with the previous serological data show the existence of a sixteenth serovar—designated serovar 16—of A. pleuropneumoniae. PMID:28053219

  8. A Unique Capsule Locus in the Newly Designated Actinobacillus pleuropneumoniae Serovar 16 and Development of a Diagnostic PCR Assay.

    PubMed

    Bossé, Janine T; Li, Yanwen; Sárközi, Rita; Gottschalk, Marcelo; Angen, Øystein; Nedbalcova, Katerina; Rycroft, Andrew N; Fodor, László; Langford, Paul R

    2017-03-01

    Actinobacillus pleuropneumoniae causes pleuropneumonia, an economically significant lung disease of pigs. Recently, isolates of A. pleuropneumoniae that were serologically distinct from the previously characterized 15 serovars were described, and a proposal was put forward that they comprised a new serovar, serovar 16. Here we used whole-genome sequencing of the proposed serovar 16 reference strain A-85/14 to confirm the presence of a unique capsular polysaccharide biosynthetic locus. For molecular diagnostics, primers were designed from the capsule locus of strain A-85/14, and a PCR was formulated that differentiated serovar 16 isolates from all 15 known serovars and other common respiratory pathogenic/commensal bacteria of pigs. Analysis of the capsule locus of strain A-85/14 combined with the previous serological data show the existence of a sixteenth serovar-designated serovar 16-of A. pleuropneumoniae.

  9. LITTLE JOE 5A - CAPSULE 14

    NASA Image and Video Library

    1961-01-01

    S61-01372 (21 Feb. 1961) --- Launch of the unmanned Mercury-Atlas 2 (MA-2) vehicle for a suborbital test flight of the Mercury capsule. The upper part of Atlas is stengthened by an eight-inch wide stainless steel band. The capsule was recovered less than one hour after launch. The altitude was 108 miles. Speed was 13,000 mph. Recovered 1,425 miles downrange. Photo credit: NASA

  10. Bioactive polysaccharides and gut microbiome (abstract)

    USDA-ARS?s Scientific Manuscript database

    Many polysaccharides have shown the ability to reduce plasma cholesterol or postprandial glycemia. Viscosity in the small intestine seems to be required to slow glucose uptake. Cereal mixed linkage beta-glucans, psyllium, glucomannans, and other polysaccharides also seem to require higher molecula...

  11. Solution NMR spectroscopy of food polysaccharides

    USDA-ARS?s Scientific Manuscript database

    Many polysaccharides are allowed for direct food use, where they serve a number of useful functions. In addition to possibly being a source of calories, a food polysaccharide may be a dietary fiber, bulking agent, crystallization inhibitor, thickener, encapsulant, gelling agent, foam and emulsion s...

  12. Polysaccharide Based Hydrogels for Biomedical Applications

    NASA Astrophysics Data System (ADS)

    Leone, Gemma; Barbucci, Rolando

    Polysaccharide based hydrogels for their physico-chemical and biological properties can be used as scaffolds for soft tissue regneration and as vehicles for drug controlled release. For both these applications, Hyaluronan shows optimal characteristics even though its quick enzymatic degradability makes this natural polysaccharide unsuitable for applications which require prolonged presence in the human organism.

  13. Towards Polymer-Based Capsules with Drastically Reduced Controlled Permeability

    NASA Astrophysics Data System (ADS)

    Andreeva, Daria V.; Sukhorukov, Gleb B.

    Small molecules (dyes, therapeutics, etc.) could be easily handled, stored, delivered, and released by polyelectrolyte capsules. To make the polyelectrolyte capsule more efficient for small molecule encapsulation, capsule permeability should be significantly decreased. Here, we demonstrate the possibility to entrap water-soluble molecular species into polyelectrolyte capsules modified by a low permeable dense polymer (polypyrrole). Possible future areas in PE capsule application as carriers for gases and volatiles in the pharmaceutical, food, and gases industry, agriculture and cosmetology are discussed.

  14. Dynamics of nonspherical compound capsules in simple shear flow

    NASA Astrophysics Data System (ADS)

    Luo, Zheng Yuan; Bai, Bo Feng

    2016-10-01

    The dynamics of an initially ellipsoidal compound capsule in a simple shear flow is investigated numerically using a three-dimensional front-tracking finite-difference model. Membrane bending resistance is included based on Helfrich's energy function besides the resistances against shear deformation and area dilatation governed by the constitutive law of Skalak et al. In this paper, we focus specifically on how the presence of a spherical inner capsule and its size affects the characteristics and transition of various dynamical states of nonspherical compound capsules (i.e., the outer capsule). Significant differences in the dynamical characteristics are observed between compound capsules and homogeneous capsules in both qualitative and quantitative terms. We find the transition from swinging to tumbling can occur at vanishing viscosity mismatch through increasing the inner capsule size alone to a critical value regardless of the initial shape of the nonspherical compound capsule (i.e., prolate or oblate). Besides, for compound capsules with viscosity mismatch, the critical viscosity ratio for the swinging-to-tumbling transition remarkably decreases by increasing the inner capsule size. It is thus concluded that the inner capsule size is a key governing parameter of compound capsule dynamics apart from the capillary number, aspect ratio, and viscosity ratio that have been long identified for homogeneous capsules. Further, we discuss the mechanisms underlying the effects of the inner capsule on the compound capsule dynamics from the viewpoint of the effective viscosity of internal fluid and find that the effects of the inner capsule on compound capsule dynamics are qualitatively similar to that of increasing the internal viscosity on homogeneous capsule dynamics. However, in quantitative terms, the compound capsule cannot be viewed as a homogeneous capsule with higher viscosity as obvious inhomogeneity in fluid stress distribution is induced by the inner membrane.

  15. Capsule production by Pseudomonas aeruginosa

    SciTech Connect

    Lynn, A.R.

    1984-01-01

    Mucoid strains of Pseudomonas aeruginosa, associated almost exclusively with chronic respiratory infections in patients with cystic fibrosis, possess a capsule composed of alginic acid similar to one produced by Azotobacter vinelandii. Recent reports have provided evidence that the biosynthetic pathway for alginate in P. aeruginosa may differ from the pathway proposed for A. vinelandii in that synthesis in P. aeruginosa may occur by way of the Entner-Doudoroff pathway. Incorporation of isotope from (6-/sup 14/C)glucose into alginate by both P. aueroginosa and A. vinelandii was 10-fold greater than that from either (1-/sup 14/C)/sup -/ or (2-/sup 14/C)glucose, indicating preferential utilization of the bottom half of the glucose molecule for alginate biosynthesis. These data strongly suggest that the Entner-Doudoroff pathway plays a major role in alginate synthesis in both P. aeruginosa and A. vinelandii. The enzymes of carbohydrate metabolism in mucoid strains of P. aeruginosa appear to be unchanged whether alignate is actively produced or not and activities do not differ significantly from nonmucoid strain PAO.

  16. CAPSULE REPORT: HARD CHROME FUME ...

    EPA Pesticide Factsheets

    All existing information which includes the information extrapolated from the Hard Chrome Pollution Prevention Demonstration Project(s) and other sources derived from plating facilities and industry contacts, will be condensed and featured in this document. At least five chromium emission prevention/control devices have been tested covering a wide spectrum of techniques currently in use at small and large-sized chrome metal plating shops. The goal for limiting chromium emissions to levels specified in the MACT Standards are: (1) 0.030 milligrams per dry standard cubic meter of air (mg/dscm) for small facilities with existing tanks, (2) 0.015 mg/dscm for small facilities with new tanks or large facilities with existing or new tanks. It should be emphasized that chemical mist suppressants still have quality issues and work practices that need to be addressed when they are used. Some of the mist suppressants currently in use are: one-, two-, and three-stage mesh pad mist eliminators; composite mesh pad mist eliminators; packed-bed scrubbers and polyballs. This capsule report should, redominantly, emphasize pollution prevention techniques and include, but not be restricted to, the afore-mentioned devices. Information

  17. Light weight escape capsule for fighter aircraft

    NASA Technical Reports Server (NTRS)

    Robert, James A.

    1988-01-01

    Emergency crew escape capabilities have been less than adequate for fighter aircraft since before WW II. From the over-the-side bailout of those days through the current ejection seat with a rocket catapult, escaping from a disabled aircraft has been risky at best. Current efforts are underway toward developing a high-tech, smart ejection seat that will give fighter pilots more room to live in the sky, but an escape capsule is needed to meet current and future fighter envelopes. Escape capsules have a bad reputation due to past examples of high weight, poor performance and great complexity. However, the advantages available demand that a capsule be developed. This capsule concept will minimize the inherent disavantages and incorporate the benefits while integrating all aspects of crew station design. The resulting design is appropriate for a crew station of the year 2010 and includes improved combat acceleration protection, chemical or biological combat capability, improved aircraft to escape system interaction, and the highest level of escape performance achievable. The capsule is compact, which can allow a reduced aircraft size and weighs only 1200 lb. The escape system weight penalty is only 120 lb higher than that for the next ejection seat and the capsule has a corresponding increase in performance.

  18. Capsule Implosion Symmetry in OMEGA Tetrahedral Hohlraums

    NASA Astrophysics Data System (ADS)

    Schnittman, J. D.; Craxton, R. S.; Pollaine, S. M.; Turner, R. E.; Wallace, J. M.; Murphy, T. J.; Delamater, N. D.; Oertel, J. A.; Hauer, A. A.; Klare, K. A.

    1998-11-01

    The 3-D time-dependent capsule implosion symmetry has been calculated for spherical hohlraums with four laser entrance holes. The code BUTTERCUP calculates the locations of beam spots on the hohlraum wall and includes a model for the absorption and x-ray conversion of the laser energy. The gold wall is heated by 1-D radiation diffusion, and radiation transport is carried out with a 3-D view-factor algorithm. A simple hydrodynamic calculation of the imploding capsule gives the resulting 3-D time-dependent drive symmetry. The predicted radiation uniformity incident on the capsule is very good ( ~1% rms) throughout the laser pulse. Experimental images of the capsule show round implosions with convergence ratios of 10 for standard capsules,(T. J. Murphy, Bull. Am. Phys. Soc. 42), 2008 (1997). in agreement with predictions. Radiation temperatures and capsule trajectories are calculated and show good agreement with experiment. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC03-92SF19460.

  19. Unexplored possibilities of all-polysaccharide composites.

    PubMed

    Simkovic, Ivan

    2013-06-20

    Composites made solely from polysaccharides are mostly ecological because they can degrade without leaving behind ecologically harmful residues, in contrast to composites which contain synthetic polymers. Herein, the following groups of all-polysaccharide composites (APCs) are discussed: an all-cellulose group that includes cotton composites, cellulose combined with other polysaccharides, as well as those based on chitin/chitosan, heparin, hyaluronan, xylan, glucomannan, pectin, xyloglucan, arabinan, starch, carrageenan, alginate, galactan as one of the components in combination with other polysaccharides. They can be used in medical, paper, food, packing, textile, electronic, mechanical engineering and other applications. The composites were tested for absorptivity, biodegradability, crystallinity, rheology, and mechanical, optical, separation, gelling, pasting, film-forming, adhesive, antimicrobial properties, as well as water vapor permeability, water repellency, dye uptake, and fire-retardancy. Except for food applications, composites based on more than two types of polysaccharides have rarely been used and many possible combinations remain unexplored.

  20. Polysaccharides in colon-specific drug delivery.

    PubMed

    Sinha, V R; Kumria, R

    2001-08-14

    Natural polysaccharides are now extensively used for the development of solid dosage forms for delivery of drug to the colon. The rationale for the development of a polysaccharide based delivery system for colon is the presence of large amounts of polysaccharidases in the human colon as the colon is inhabited by a large number and variety of bacteria which secrete many enzymes e.g. beta-D-glucosidase, beta-D-galactosidase, amylase, pectinase, xylanase, beta-D-xylosidase, dextranase, etc. Various major approaches utilizing polysaccharides for colon-specific delivery are fermentable coating of the drug core, embedding of the drug in biodegradable matrix, formulation of drug-saccharide conjugate (prodrugs). A large number of polysaccharides have already been studied for their potential as colon-specific drug carrier systems, such as chitosan, pectin, chondroitin sulphate, cyclodextrin, dextrans, guar gum, inulin, amylose and locust bean gum. Recent efforts and approaches exploiting these polysaccharides in colon-specific drug delivery are discussed.

  1. The ESX-5 System of Pathogenic Mycobacteria Is Involved In Capsule Integrity and Virulence through Its Substrate PPE10

    PubMed Central

    Ates, Louis S.; van der Woude, Aniek D.; Bestebroer, Jovanka; van Stempvoort, Gunny; Musters, René J. P.; Garcia-Vallejo, Juan J.; Picavet, Daisy I.; van de Weerd, Robert; Maletta, Massimiliano; Kuijl, Coenraad P.; van der Wel, Nicole N.; Bitter, Wilbert

    2016-01-01

    Mycobacteria produce a capsule layer, which consists of glycan-like polysaccharides and a number of specific proteins. In this study, we show that, in slow-growing mycobacteria, the type VII secretion system ESX-5 plays a major role in the integrity and stability of the capsule. We have identified PPE10 as the ESX-5 substrate responsible for this effect. Mutants in esx-5 and ppe10 both have impaired capsule integrity as well as reduced surface hydrophobicity. Electron microscopy, immunoblot and flow cytometry analyses demonstrated reduced amounts of surface localized proteins and glycolipids, and morphological differences in the capsular layer. Since capsular proteins secreted by the ESX-1 system are important virulence factors, we tested the effect of the mutations that cause capsular defects on virulence mechanisms. Both esx-5 and ppe10 mutants of Mycobacterium marinum were shown to be impaired in ESX-1-dependent hemolysis. In agreement with this, the ppe10 and esx5 mutants showed reduced recruitment of ubiquitin in early macrophage infection and intermediate attenuation in zebrafish embryos. These results provide a pivotal role for the ESX-5 secretion system and its substrate PPE10, in the capsular integrity of pathogenic mycobacteria. These findings open up new roads for research on the mycobacterial capsule and its role in virulence and immune modulation. PMID:27280885

  2. Endotoxin, capsule, and bacterial attachment contribute to Neisseria meningitidis resistance to the human antimicrobial peptide LL-37.

    PubMed

    Jones, Allison; Geörg, Miriam; Maudsdotter, Lisa; Jonsson, Ann-Beth

    2009-06-01

    Pathogenic bacteria have evolved numerous mechanisms to evade the human immune system and have developed widespread resistance to traditional antibiotics. We studied the human pathogen Neisseria meningitidis and present evidence of novel mechanisms of resistance to the human antimicrobial peptide LL-37. We found that bacteria attached to host epithelial cells are resistant to 10 microM LL-37 whereas bacteria in solution or attached to plastic are killed, indicating that the cell microenvironment protects bacteria. The bacterial endotoxin lipooligosaccharide and the polysaccharide capsule contribute to LL-37 resistance, probably by preventing LL-37 from reaching the bacterial membrane, as more LL-37 reaches the bacterial membrane on both lipooligosaccharide-deficient and capsule-deficient mutants whereas both mutants are also more susceptible to LL-37 killing than the wild-type strain. N. meningitidis bacteria respond to sublethal doses of LL-37 and upregulate two of their capsule genes, siaC and siaD, which further results in upregulation of capsule biosynthesis.

  3. HYDROCARBON VAPOR DIFFUSION IN INTACT CORE SLEEVES

    EPA Science Inventory

    The diffusion of 2,2,4-trimethylpentane (TMP) and 2,2,5-trimethylhexane (TMH) vapors put of residually contaminated sandy soil from the U.S. Environmental Protection Agency (EPA) field research site at Traverse City, Michigan, was measured and modeled. The headspace of an intact ...

  4. HYDROCARBON VAPOR DIFFUSION IN INTACT CORE SLEEVES

    EPA Science Inventory

    The diffusion of 2,2,4-trimethylpentane (TMP) and 2,2,5-trimethylhexane (TMH) vapors put of residually contaminated sandy soil from the U.S. Environmental Protection Agency (EPA) field research site at Traverse City, Michigan, was measured and modeled. The headspace of an intact ...

  5. Extensive Capsule Locus Variation and Large-Scale Genomic Recombination within the Klebsiella pneumoniae Clonal Group 258.

    PubMed

    Wyres, Kelly L; Gorrie, Claire; Edwards, David J; Wertheim, Heiman F L; Hsu, Li Yang; Van Kinh, Nguyen; Zadoks, Ruth; Baker, Stephen; Holt, Kathryn E

    2015-04-10

    Klebsiella pneumoniae clonal group (CG) 258, comprising sequence types (STs) 258, 11, and closely related variants, is associated with dissemination of the K. pneumoniae carbapenemase (KPC). Hospital outbreaks of KPC CG258 infections have been observed globally and are very difficult to treat. As a consequence, there is renewed interest in alternative infection control measures such as vaccines and phage or depolymerase treatments targeting the K. pneumoniae polysaccharide capsule. To date, 78 immunologically distinct capsule variants have been described in K. pneumoniae. Previous investigations of ST258 and a small number of closely related strains suggested that capsular variation was limited within this clone; only two distinct ST258 capsule polysaccharide synthesis (cps) loci have been identified, both acquired through large-scale recombination events (>50 kb). In contrast to previous studies, we report a comparative genomic analysis of the broader K. pneumoniae CG258 (n = 39). We identified 11 different cps loci within CG258, indicating that capsular switching is actually common within the complex. We observed several insertion sequences (IS) within the cps loci, and show further intraclone diversification of two cps loci through IS activity. Our data also indicate that several large-scale recombination events have shaped the genomes of CG258, and that definition of the complex should be broadened to include ST395 (also reported to harbor KPC). As only the second report of extensive intraclonal cps variation among Gram-negative bacterial species, our findings alter our understanding of the evolution of these organisms and have key implications for the design of control measures targeting K. pneumoniae capsules.

  6. Small Particles Intact Capture Experiment (SPICE)

    NASA Technical Reports Server (NTRS)

    Nishioka, Ken-Ji; Carle, G. C.; Bunch, T. E.; Mendez, David J.; Ryder, J. T.

    1994-01-01

    The Small Particles Intact Capture Experiment (SPICE) will develop technologies and engineering techniques necessary to capture nearly intact, uncontaminated cosmic and interplanetary dust particles (IDP's). Successful capture of such particles will benefit the exobiology and planetary science communities by providing particulate samples that may have survived unaltered since the formation of the solar system. Characterization of these particles may contribute fundamental data to our knowledge of how these particles could have formed into our planet Earth and, perhaps, contributed to the beginnings of life. The term 'uncontaminated' means that captured cosmic and IDP particles are free of organic contamination from the capture process and the term 'nearly intact capture' means that their chemical and elemental components are not materially altered during capture. The key to capturing cosmic and IDP particles that are organic-contamination free and nearly intact is the capture medium. Initial screening of capture media included organic foams, multiple thin foil layers, and aerogel (a silica gel); but, with the exception of aerogel, the requirements of no contamination or nearly intact capture were not met. To ensure no contamination of particles in the capture process, high-purity aerogel was chosen. High-purity aerogel results in high clarity (visual clearness), a useful quality in detection and recovery of embedded captured particles from the aerogel. P. Tsou at the Jet Propulsion Laboratory (JPL) originally described the use of aerogel for this purpose and reported laboratory test results. He has flown aerogel as a 'GAS-can Lid' payload on STS-47 and is evaluating the results. The Timeband Capture Cell Experiment (TICCE), a Eureca 1 experiment, is also flying aerogel and is scheduled for recovery in late April.

  7. Small Particles Intact Capture Experiment (SPICE)

    NASA Technical Reports Server (NTRS)

    Nishioka, Ken-Ji; Carle, G. C.; Bunch, T. E.; Mendez, David J.; Ryder, J. T.

    1994-01-01

    The Small Particles Intact Capture Experiment (SPICE) will develop technologies and engineering techniques necessary to capture nearly intact, uncontaminated cosmic and interplanetary dust particles (IDP's). Successful capture of such particles will benefit the exobiology and planetary science communities by providing particulate samples that may have survived unaltered since the formation of the solar system. Characterization of these particles may contribute fundamental data to our knowledge of how these particles could have formed into our planet Earth and, perhaps, contributed to the beginnings of life. The term 'uncontaminated' means that captured cosmic and IDP particles are free of organic contamination from the capture process and the term 'nearly intact capture' means that their chemical and elemental components are not materially altered during capture. The key to capturing cosmic and IDP particles that are organic-contamination free and nearly intact is the capture medium. Initial screening of capture media included organic foams, multiple thin foil layers, and aerogel (a silica gel); but, with the exception of aerogel, the requirements of no contamination or nearly intact capture were not met. To ensure no contamination of particles in the capture process, high-purity aerogel was chosen. High-purity aerogel results in high clarity (visual clearness), a useful quality in detection and recovery of embedded captured particles from the aerogel. P. Tsou at the Jet Propulsion Laboratory (JPL) originally described the use of aerogel for this purpose and reported laboratory test results. He has flown aerogel as a 'GAS-can Lid' payload on STS-47 and is evaluating the results. The Timeband Capture Cell Experiment (TICCE), a Eureca 1 experiment, is also flying aerogel and is scheduled for recovery in late April.

  8. Recombinant Escherichia coli K5 strain with the deletion of waaR gene decreases the molecular weight of the heparosan capsular polysaccharide.

    PubMed

    Huang, Haichan; Liu, Xiaobo; Lv, Shencong; Zhong, Weihong; Zhang, Fuming; Linhardt, Robert J

    2016-09-01

    Heparosan, the capsular polysaccharide of Escherichia coli K5 having a carbohydrate backbone similar to that of heparin, has become a potential precursor for bioengineering heparin. In the heparosan biosynthesis pathway, the gene waaR encoding α-1-, 2- glycosyltransferase catalyze s the third glucosyl residues linking to the oligosaccharide chain. In the present study, a waaR deletion mutant of E. coli K5 was constructed. The mutant showed improvement of capsule polysaccharide yield. It is interesting that the heparosan molecular weight of the mutant is reduced and may become more suitable as a precursor for the production of low molecular weight heparin derived from the wild-type K5 capsular polysaccharide.

  9. Thin film of biocompatible polysaccharides

    NASA Astrophysics Data System (ADS)

    Richert, Ludovic; Lavalle, Philippe; Schaaf, Pierre; Voegel, Jean-Claude; Picart, Catherine

    2003-03-01

    The layer-by-layer deposition method proposed by Decher et al. (1991) is a very simple and versatile method used to build thin films. These films are of interest for bioengineering because of their unique properties and of the possible insertion of bioactive molecules. We present here the peculiar properties of a new kind of film formed with natural biopolymers, namely hyaluronan (HA)and chitosan (CHI). The films may be used as biomimetic substrates to control bacterial and cell adhesion. These polysaccharides are of particular interest because they are biodegradable, non toxic, and can be found in various tissues. Hyaluronan is also a natural ligand for a numerous type of cells through the CD44 receptor. Chitosan has already largely been used for its biological and anti-microbial properties. (CHI/HA) films were built in acidic pH at different ionic strength. The buildup was followed in situ by optical waveguide lightmode spectroscopy (OWLS), quartz crystal microbalance, streaming potential measurements and atomic force microscopy. The kinetics of adsorption and desorption of the polyelectrolytes depended on the ionic strength. Small islands were initially present on the surface which grew by mutual coalescence until becoming a flat film. The films were around 200 nm in thickness. These results suggest that different types of thin films constituted of polysaccharides can be built on any type of surface. These films are currently investigated toward their cell adhesion and bacterial adhesion properties.

  10. Synthesis of part structures of Cryptococcus neoformans serotype C capsular polysaccharide.

    PubMed

    Guazzelli, Lorenzo; McCabe, Orla; Oscarson, Stefan

    2016-10-04

    Cryptococcus neoformans is a fungal pathogen that can cause life-threatening infections in immunocompromised patients. The development of a vaccine based on the capsular polysaccharide of C. neoformans is still an open challenge due to the heterogeneity of the capsular polysaccharide and the difficulty of identifying protective epitopes. Therefore, construction of structurally defined part structures of the C. neoformans GXM capsule is in great demand. Herein is presented the synthesis of a 3-O-naphthalenylmethyl protected trisaccharide thioglycoside building block which is present in C. neoformans serotype C polysaccharide. Its property as a donor in a glycosylation reaction with a model acceptor has been evaluated together with its behaviour as an acceptor following removal of the temporary protecting group. The heavily branched hexasaccharide was obtained in good yields and excellent α-selectivity. The frame shifted octasaccharide structural triad motif for serotype C was also prepared following the same building block strategy. For the first time this structural motif, which is the most substituted amongst the four C. neoformans serotypes, was prepared. Three synthesized C. neoformans serotype C fragments of varying size, from penta-up to octasaccharide, were deprotected and will be included in unique glycoarrays to further investigate the possibility to develop a synthetic vaccine against this pathogen.

  11. Comparative skeletal muscle histopathologic and ultrastructural features in two forms of polysaccharide storage myopathy in horses.

    PubMed

    McCue, M E; Armién, A G; Lucio, M; Mickelson, J R; Valberg, S J

    2009-11-01

    Polysaccharide storage myopathy (PSSM) has been found in more than 35 different horse breeds through identification of abnormal storage of polysaccharide in muscle biopsies. A dominant mutation in the glycogen synthase 1 gene (GYS1) accounts for a substantial proportion of PSSM cases in at least 17 breeds, including Quarter Horses, but some horses diagnosed with PSSM by muscle histopathologic analysis are negative for the mutation. We hypothesized that a second distinct form of glycogen storage disease exists in GYS1-negative horses with PSSM. The objectives of this study were to compare the histopathologic features, ultrastructure of polysaccharide, signalment, history, and presenting complaints of GYS1-negative Quarter Horses and related breeds with PSSM to those of GYS1-positive horses with PSSM. The total histopathologic score in frozen sections of skeletal muscle stained with hematoxylin and eosin, periodic acid Schiff (PAS) and amylase-PAS stains from 53 GYS1-negative horses did not differ from that of 52 GYS1-positive horses. Abnormal polysaccharide was fine granular or homogenous in appearance (49/53; 92%), often amylase-sensitive (28/53; 53%), more commonly located under the sarcolemma, and consisting of beta glycogen particles in GYS1-negative horses. However, in GYS1-positive horses, abnormal polysaccharide was usually coarse granular (50/52; 96%), amylase-resistant (51/52; 98%), more commonly cytoplasmic, and consisting of beta glycogen particles or, in some myofibers, filamentous material surrounded by beta glycogen particles. Retrospective analysis found that GYS1-negative horses (n = 43) were younger at presentation (4.9 +/- 0.6 years vs. 6.7 +/- 0.3 years for GYS1-positive horses) and were more likely to be intact males than GYS1-positive horses (n = 160). We concluded that 2 forms of PSSM exist and often have distinctive abnormal polysaccharide. However, because evaluation of the histologic appearance of polysaccharide can be subjective and

  12. Capsule endoscopy in neoplastic diseases.

    PubMed

    Pennazio, Marco; Rondonotti, Emanuele; de Franchis, Roberto

    2008-09-14

    Until recently, diagnosis and management of small-bowel tumors were delayed by the difficulty of access to the small bowel and the poor diagnostic capabilities of the available diagnostic techniques. An array of new methods has recently been developed, increasing the possibility of detecting these tumors at an earlier stage. Capsule endoscopy (CE) appears to be an ideal tool to recognize the presence of neoplastic lesions along this organ, since it is non-invasive and enables the entire small bowel to be visualized. High-quality images of the small-bowel mucosa may be captured and small and flat lesions recognized, without exposure to radiation. Recent studies on a large population of patients undergoing CE have reported small-bowel tumor frequency only slightly above that reported in previous surgical series (range, 1.6%-2.4%) and have also confirmed that the main clinical indication to CE in patients with small-bowel tumors is obscure gastrointestinal (GI) bleeding. The majority of tumors identified by CE are malignant; many were unsuspected and not found by other methods. However, it remains difficult to identify pathology and tumor type based on the lesion's endoscopic appearance. Despite its limitations, CE provides crucial information leading in most cases to changes in subsequent patient management. Whether the use of CE in combination with other new diagnostic (MRI or multidetector CT enterography) and therapeutic (Push-and-pull enteroscopy) techniques will lead to earlier diagnosis and treatment of these neoplasms, ultimately resulting in a survival advantage and in cost savings, remains to be determined through carefully-designed studies.

  13. 3D Printed Programmable Release Capsules.

    PubMed

    Gupta, Maneesh K; Meng, Fanben; Johnson, Blake N; Kong, Yong Lin; Tian, Limei; Yeh, Yao-Wen; Masters, Nina; Singamaneni, Srikanth; McAlpine, Michael C

    2015-08-12

    The development of methods for achieving precise spatiotemporal control over chemical and biomolecular gradients could enable significant advances in areas such as synthetic tissue engineering, biotic-abiotic interfaces, and bionanotechnology. Living organisms guide tissue development through highly orchestrated gradients of biomolecules that direct cell growth, migration, and differentiation. While numerous methods have been developed to manipulate and implement biomolecular gradients, integrating gradients into multiplexed, three-dimensional (3D) matrices remains a critical challenge. Here we present a method to 3D print stimuli-responsive core/shell capsules for programmable release of multiplexed gradients within hydrogel matrices. These capsules are composed of an aqueous core, which can be formulated to maintain the activity of payload biomolecules, and a poly(lactic-co-glycolic) acid (PLGA, an FDA approved polymer) shell. Importantly, the shell can be loaded with plasmonic gold nanorods (AuNRs), which permits selective rupturing of the capsule when irradiated with a laser wavelength specifically determined by the lengths of the nanorods. This precise control over space, time, and selectivity allows for the ability to pattern 2D and 3D multiplexed arrays of enzyme-loaded capsules along with tunable laser-triggered rupture and release of active enzymes into a hydrogel ambient. The advantages of this 3D printing-based method include (1) highly monodisperse capsules, (2) efficient encapsulation of biomolecular payloads, (3) precise spatial patterning of capsule arrays, (4) "on the fly" programmable reconfiguration of gradients, and (5) versatility for incorporation in hierarchical architectures. Indeed, 3D printing of programmable release capsules may represent a powerful new tool to enable spatiotemporal control over biomolecular gradients.

  14. Capsule endoscopy in refractory celiac disease.

    PubMed

    Daum, S; Wahnschaffe, U; Glasenapp, R; Borchert, M; Ullrich, R; Zeitz, M; Faiss, S

    2007-05-01

    Patients with refractory celiac disease (RCD) are at risk of intestinal T-cell lymphoma, which is difficult to diagnose because it often develops in the small bowel. We therefore studied whether wireless capsule endoscopy was able to detect ulcerative jejunitis or intestinal T-cell lymphomas that were missed by standard endoscopic and imaging procedures in patients with RCD. Detection of ulcerative jejunitis and overt T-cell lymphoma by capsule endoscopy or by upper and lower endoscopy, abdominal computed tomography (CT) or abdominal magnetic resonance tomography (MRT) was compared in 14 consecutive patients with RCD: in seven patients who showed loss of T-cell antigens on intraepithelial lymphocytes and/or clonality of the T-cell receptor gene (i. e. type II RCD) and in seven patients who did not have these features (i. e. type I RCD). Complete evaluation of the small bowel by capsule endoscopy was achieved in 9/14 patients. Signs of ulcerative jejunitis or intestinal T-cell lymphoma, affecting further clinical management, were found in two patients with type II RCD: in one patient these signs were found only by capsule endoscopy (ulcerations and stenosis) and in another patient the abnormalities were identified by CT/MRT (mesenteric lymph nodes harboring lymphoma). No clinically relevant abnormalities were found in patients with type I RCD by lower endoscopy or by small-bowel imaging (capsule endoscopy, CT, or MRT). In patients with type II RCD, capsule endoscopy can detect additional cases with ulcerative jejunitis and could be included in the diagnostic armamentarium, subject to confirmation by larger series. In patients with type I RCD, our study confirmed the low diagnostic yield of imaging procedures, including wireless capsule endoscopy.

  15. Enzymatic method for improving the injectability of polysaccharides

    DOEpatents

    Griffith, William L.; Compere, Alicia L.; Holleman, James W.

    1982-01-01

    A method for enhancing the ability of polysaccharides in aqueous solution to flow through a porous medium comprises contacting the polysaccharides with an endoenzyme capable of hydrolyzing at least one of the linkages of the sugar units of the polysaccharides and maintaining the polysaccharides in contact with the enzyme under hydrolysis conditions for a time sufficient to decrease the tendency of the polysaccharides to plug the porous medium yet insufficient to decrease the viscosity of the aqueous polysaccharides by more than 25%. The partially hydrolyzed polysaccharides are useful as thickening agents for flooding water used to recover oil from oil-containing subterranean formations.

  16. Xenopus egg cytoplasm with intact actin.

    PubMed

    Field, Christine M; Nguyen, Phuong A; Ishihara, Keisuke; Groen, Aaron C; Mitchison, Timothy J

    2014-01-01

    We report optimized methods for preparing Xenopus egg extracts without cytochalasin D, that we term "actin-intact egg extract." These are undiluted egg cytoplasm that contains abundant organelles, and glycogen which supplies energy, and represents the least perturbed cell-free cytoplasm preparation we know of. We used this system to probe cell cycle regulation of actin and myosin-II dynamics (Field et al., 2011), and to reconstitute the large, interphase asters that organize early Xenopus embryos (Mitchison et al., 2012; Wühr, Tan, Parker, Detrich, & Mitchison, 2010). Actin-intact Xenopus egg extracts are useful for analysis of actin dynamics, and interaction of actin with other cytoplasmic systems, in a cell-free system that closely mimics egg physiology, and more generally for probing the biochemistry and biophysics of the egg, zygote, and early embryo. Detailed protocols are provided along with assays used to check cell cycle state and tips for handling and storing undiluted egg extracts.

  17. Capsule structure of Proteus mirabilis (ATCC 49565).

    PubMed Central

    Beynon, L M; Dumanski, A J; McLean, R J; MacLean, L L; Richards, J C; Perry, M B

    1992-01-01

    Proteus mirabilis 2573 (ATCC 49565) produces an acidic capsular polysaccharide which was shown from glycose analysis, carboxyl reduction, methylation, periodate oxidation, and the application of one dimensional and two-dimensional high-resolution nuclear magnetic resonance techniques to be a high-molecular-weight polymer of branched trisaccharide units composed of 2-acetamido-2-deoxy-D-glucose (N-acetyl-D-glucosamine), 2-acetamido-2,6-dideoxy-L-galactose (N-acetyl-L-fucosamine), and D-glucuronic acid, having the structure: [formula: see text] P. mirabilis 2573 also produces an O:6 serotype lipopolysaccharide in which the O-chain component has the same structure as the homologous capsular polysaccharide. This is the first report of a defined capsular polysaccharide in this bacterial genus. PMID:1551839

  18. Silica Aerogel Captures Cosmic Dust Intact

    NASA Technical Reports Server (NTRS)

    Tsou, P.

    1994-01-01

    The mesostructure of silica aerogel resembles stings of grapes, ranging in size from 10 to 100 angstrom. This fine mesostructure transmits nearly 90 percent of incident light in the visible, while providing sufficiently gentle dissipation of the kinetric energy of hypervelocity cosmic dust particles to permit their intact capture. We introduced silica aerogel in 1987 as capture medium to take advantage of its low density, fine mesostruicture and most importantly, its transparency, allowing optical location of captured micron sized particles.

  19. Silica Aerogel Captures Cosmic Dust Intact

    NASA Technical Reports Server (NTRS)

    Tsou, P.

    1994-01-01

    The mesostructure of silica aerogel resembles stings of grapes, ranging in size from 10 to 100 angstrom. This fine mesostructure transmits nearly 90 percent of incident light in the visible, while providing sufficiently gentle dissipation of the kinetric energy of hypervelocity cosmic dust particles to permit their intact capture. We introduced silica aerogel in 1987 as capture medium to take advantage of its low density, fine mesostruicture and most importantly, its transparency, allowing optical location of captured micron sized particles.

  20. Scaling effects in spiral capsule robots.

    PubMed

    Liang, Liang; Hu, Rong; Chen, Bai; Tang, Yong; Xu, Yan

    2017-04-01

    Spiral capsule robots can be applied to human gastrointestinal tracts and blood vessels. Because of significant variations in the sizes of the inner diameters of the intestines as well as blood vessels, this research has been unable to meet the requirements for medical applications. By applying the fluid dynamic equations, using the computational fluid dynamics method, to a robot axial length ranging from 10(-5) to 10(-2) m, the operational performance indicators (axial driving force, load torque, and maximum fluid pressure on the pipe wall) of the spiral capsule robot and the fluid turbulent intensity around the robot spiral surfaces was numerically calculated in a straight rigid pipe filled with fluid. The reasonableness and validity of the calculation method adopted in this study were verified by the consistency of the calculated values by the computational fluid dynamics method and the experimental values from a relevant literature. The results show that the greater the fluid turbulent intensity, the greater the impact of the fluid turbulence on the driving performance of the spiral capsule robot and the higher the energy consumption of the robot. For the same level of size of the robot, the axial driving force, the load torque, and the maximum fluid pressure on the pipe wall of the outer spiral robot were larger than those of the inner spiral robot. For different requirements of the operating environment, we can choose a certain kind of spiral capsule robot. This study provides a theoretical foundation for spiral capsule robots.

  1. Capsule HRB-21 postirradiation examination plan

    SciTech Connect

    Packan, N.H.; Kania, M.J.; Shrader, L.G.

    1990-03-01

    Irradiation capsule HRB-21 is a test capsule designed to provide Modular High-Temperature Gas-Cooled Reactor (MHTGR) coated particle fuel performance data under test reactor conditions representative of normal MHTGR operation. The irradiated fuel will also be used for postirradiation heating in a controlled atmosphere allowing acquisition of fission product release data at sustained high temperatures. The in-reactor performance data, the postirradiation examination data, and the postirradiation heating data will be used for the validation of fuel performance models under normal and off-normal operating conditions. The accelerated irradiation is to take place in the High Flux Isotope Reactor (HFIR) at ORNL. This report identifies the procedures to be followed in carrying out the postirradiation disassembly and examination of HRB-21. Included is a description of the capsule, a detailed sequence of steps for disassembly of the capsule, a description of the postirradiation examination techniques to be employed, and specifications for the storage of capsule components and the reporting of results. 9 refs., 6 figs., 2 tabs.

  2. Vacuum Ultraviolet Action Spectroscopy of Polysaccharides

    NASA Astrophysics Data System (ADS)

    Enjalbert, Quentin; Brunet, Claire; Vernier, Arnaud; Allouche, Abdul-Rahman; Antoine, Rodolphe; Dugourd, Philippe; Lemoine, Jérôme; Giuliani, Alexandre; Nahon, Laurent

    2013-08-01

    We studied the optical properties of gas-phase polysaccharides (maltose, maltotetraose, and maltohexaose) ions by action spectroscopy using the coupling between a quadrupole ion trap and a vacuum ultraviolet (VUV) beamline at the SOLEIL synchrotron radiation facility (France) in the 7 to 18 eV range. The spectra provide unique benchmarks for evaluation of theoretical data on electronic transitions of model carbohydrates in the VUV range. The effects of the nature of the charge held by polysaccharide ions on the relaxation processes were also explored. Finally the effect of isomerization of polysaccharides (with melezitose and raffinose) on their photofragmentation with VUV photons is presented.

  3. A scintigraphic investigation of the disintegration behaviour of capsules in fasting subjects: a comparison of hypromellose capsules containing carrageenan as a gelling agent and standard gelatin capsules.

    PubMed

    Tuleu, C; Khela, M K; Evans, D F; Jones, B E; Nagata, S; Basit, A W

    2007-03-01

    Two-piece hard shell capsules made from hypromellose (or hydroxypropyl methylcellulose, HPMC) have been proposed as an alternative to conventional gelatin capsules for oral drug delivery; however, little is known about their in vivo behaviour. The aim of this study was to compare the disintegration of HPMC and gelatin capsules in fasted human subjects using the technique of gamma scintigraphy. HPMC capsules containing carrageenan as a gelling agent (QUALI-V(R), Qualicaps) and gelatin capsules (Qualicaps) of size 0 were filled with a lactose-based mixture. The capsules were separately radiolabelled with indium-111 and technetium-99m. Both capsules were administered simultaneously with 180ml water to eight healthy male subjects following an overnight fast. Each volunteer was positioned in front of the gamma camera and sequential 60s images were acquired in a continuous manner for 30min. No differences in the oesophageal transit of the two types of capsules were noted, with the capsules arriving in the stomach in a matter of seconds. All the capsules disintegrated in the stomach. The mean (+/-S.D.) disintegration time for the HPMC capsules was 9+/-2min (range 6-11min). The corresponding mean time for the gelatin capsules was 7+/-4min (range 3-13min). These disintegration times were not significantly different (P=0.108, paired t-test). In conclusion, HPMC and gelatin capsules show rapid and comparable in vivo disintegration times in the fasted state. HPMC capsules containing carrageenan as a gelling agent therefore offer a practical alternative to gelatin capsules as an oral drug delivery carrier.

  4. Increased genetic diversity of Neisseria meningitidis isolates after the introduction of meningococcal serogroup C polysaccharide conjugate vaccines.

    PubMed

    Diggle, Mathew A; Clarke, Stuart C

    2005-09-01

    During the 1990s, the incidence of meningococcal disease was high in the United Kingdom. This was due primarily to an increase in serogroup C disease, particularly that within the ET-37/ST-11 genetic lineage. Serogroup C meningococcal polysaccharide conjugate vaccines were introduced in the United Kingdom in 1999, but the sequence types of meningococci causing disease since that time have not yet been reported. We have used serogrouping and multilocus sequence typing to characterize meningococci from patients with invasive disease over a 4-year period and show that there is a significant increase in genetic diversity but no genetic evidence of capsule switching.

  5. Sequence analysis and molecular characterization of genes required for the biosynthesis of type 1 capsular polysaccharide in Staphylococcus aureus.

    PubMed

    Lin, W S; Cunneen, T; Lee, C Y

    1994-11-01

    We previously cloned a 19.4-kb DNA region containing a cluster of genes affecting type 1 capsule production from Staphylococcus aureus M. Subcloning experiments showed that these capsule (cap) genes are localized in a 14.6-kb region. Sequencing analysis of the 14.6-kb fragment revealed 13 open reading frames (ORFs). Using complementation tests, we have mapped a collection of Cap- mutations in 10 of the 13 ORFs, indicating that these 10 genes are involved in capsule biosynthesis. The requirement for the remaining three ORFs in the synthesis of the capsule was demonstrated by constructing site-specific mutations corresponding to each of the three ORFs. Using an Escherichia coli S30 in vitro transcription-translation system, we clearly identified 7 of the 13 proteins predicted from the ORFs. Homology search between the predicted proteins and those in the data bank showed very high homology (52.3% identity) between capL and vipA, moderate homology (29% identity) between capI and vipB, and limited homology (21.8% identity) between capM and vipC. The vipA, vipB, and vipC genes have been shown to be involved in the biosynthesis of Salmonella typhi Vi antigen, a homopolymer polysaccharide consisting of N-acetylgalactosamino uronic acid, which is also one of the components of the staphylococcal type 1 capsule. The homology between these sets of genes therefore suggests that capL, capI, and capM may be involved in the biosynthesis of amino sugar, N-acetylgalactosamino uronic acid. In addition, the search showed that CapG aligned well with the consensus sequence of a family of acetyltransferases from various prokaryotic organisms, suggesting that CapG may be an acetyltransferase. Using the isogenic Cap- and Cap+ strains constructed in this study, we have confirmed that type 1 capsule is an important virulence factor in a mouse lethality test.

  6. A capsule conjugate vaccine approach to prevent diarrheal disease caused by Campylobacter jejuni

    PubMed Central

    Maue, Alexander C; Poly, Frédéric; Guerry, Patricia

    2014-01-01

    Campylobacter jejuni is a major cause of diarrheal disease and results in high levels of morbidity and economic loss in both industrialized and developing regions of the world. To date, prior vaccine approaches have failed to confer protection against this enteric pathogen. Key challenges to the development of a practical Campylobacter vaccine for human use include a lack of understanding of Campylobacter pathogenesis and well-defined immune correlates of protection. With the discovery that C. jejuni expresses a capsule polysaccharide associated with virulence, a conjugate vaccine approach is currently being evaluated. Conjugate vaccines have been successfully developed and implemented against other invasive mucosal pathogens including Streptococcus pneumoniae, Neisseria meningitidis,and Hemophilus influenzae. Furthermore, Shigella-based conjugate vaccines based on lipopolysaccharide have shown promising results in field trials. A prototype C. jejuni conjugate vaccine is currently entering human testing. PMID:24632556

  7. Serogroup quantitation of multivalent polysaccharide and polysaccharide-conjugate meningococcal vaccines from China.

    PubMed

    Cook, Matthew C; Gibeault, Sabrina; Filippenko, Vasilisa; Ye, Qiang; Wang, Junzhi; Kunkel, Jeremy P

    2013-07-01

    The active components of most meningococcal vaccines are four antigenic serogroup capsular polysaccharides (A, C, Y, W135). The vaccines, monovalent or multivalent mixtures of either free polysaccharides or polysaccharides conjugated to antigenic carrier proteins, may be in liquid or lyophilised formulations, with or without excipients. Acid hydrolysis and chromatographic methods for serogroup quantitation, which were previously optimised and qualified using polysaccharide-based standards and a narrow range of real vaccines, are here challenged with multiple lots of a broad assortment of additional multivalent polysaccharide-based meningococcal vaccine products. Centrifugal filtration successfully removed all interfering lactose excipient without loss of polysaccharides to allow for the determination of Y and W135 serogroups. Replicate operations by three different analysts indicated high method reproducibility. Results indicated some lot-to-lot and product-to-product variations. However, all vaccines were within general specifications for each serogroup polysaccharide, with the exception of all lots of one polysaccharide vaccine - which by these methods were found to be deficient in the serogroup A component only. These robust techniques are very useful for the evaluation of antigen content and consistency of manufacture. The deformulation, hydrolysis and chromatographic methods may be adaptable for the evaluation of other types of polysaccharide-based vaccines.

  8. Adhesive capsulitis: a review of current treatment.

    PubMed

    Neviaser, Andrew S; Hannafin, Jo A

    2010-11-01

    Adhesive capsulitis is characterized by a painful, gradual loss of both active and passive glenohumeral motion resulting from progressive fibrosis and ultimate contracture of the glenohumeral joint capsule. Variable nomenclature, inconsistent reporting of disease staging, and a multitude of different treatments have created a confusing and contradictory body of literature about this condition. Our purpose is to review the evidence for both nonsurgical and surgical management of adhesive capsulitis with an emphasis on level I and II studies when available. Significant deficits in the literature include a paucity of randomized controlled trials, failure to report response to treatment in a stage-based fashion, and an incomplete understanding of the disease's natural course. Recognition that the clinical stages reflect a progression in the underlying pathological changes should guide future treatments.

  9. Spectral measurements of asymmetrically irradiated capsule backlighters

    DOE PAGES

    Keiter, P. A.; Drake, R. P.

    2016-09-09

    Capsule backlighters provide a quasi-continuum x-ray spectrum over a wide range of photon energies. Ideally one irradiates the capsule backlighter symmetrically, however, in complex experimental geometries, this is not always possible. In recent experiments we irradiated capsule backlighters asymmetrically and measured the x-ray spectrum from multiple directions. We will present time-integrated spectra over the photon energy range of ~2-13 keV and time-resolved spectra over the photon energy range of ~2-3 keV. Lastly, we will compare the spectra from different lines of sight to determine if the laser asymmetry results in an angular dependence in the x-ray emission.

  10. Capsule endoscopy—A mechatronics perspective

    NASA Astrophysics Data System (ADS)

    Lin, Lin; Rasouli, Mahdi; Kencana, Andy Prima; Tan, Su Lim; Wong, Kai Juan; Ho, Khek Yu; Phee, Soo Jay

    2011-03-01

    The recent advances in integrated circuit technology, wireless communication, and sensor technology have opened the door for development of miniature medical devices that can be used for enhanced monitoring and treatment of medical conditions. Wireless capsule endoscopy is one of such medical devices that has gained significant attention during the past few years. It is envisaged that future wireless capsule endoscopies replace traditional endoscopy procedures by providing advanced functionalities such as active locomotion, body fluid/tissue sampling, and drug delivery. Development of energy-efficient miniaturized actuation mechanisms is a key step toward achieving this goal. Here, we review some of the actuators that could be integrated into future wireless capsules and discuss the existing challenges.

  11. Unsteady Pressures on a Generic Capsule Shape

    NASA Technical Reports Server (NTRS)

    Burnside, Nathan; Ross, James C.

    2015-01-01

    While developing the aerodynamic database for the Orion spacecraft, the low-speed flight regime (transonic and below) proved to be the most difficult to predict and measure accurately. The flow over the capsule heat shield in descent flight was particularly troublesome for both computational and experimental efforts due to its unsteady nature and uncertainty about the boundary layer state. The data described here were acquired as part of a study to improve the understanding of the overall flow around a generic capsule. The unsteady pressure measurements acquired on a generic capsule shape are presented along with a discussion about the effects of various flight conditions and heat-shield surface roughness on the resulting pressure fluctuations.

  12. Spectral measurements of asymmetrically irradiated capsule backlighters

    NASA Astrophysics Data System (ADS)

    Keiter, P. A.; Drake, R. P.

    2016-11-01

    Capsule backlighters provide a quasi-continuum x-ray spectrum over a wide range of photon energies [J. F. Hansen et al., Rev. Sci. Instrum. 79, 013504 (2008)]. Ideally one irradiates the capsule backlighter symmetrically, however, in complex experimental geometries, this is not always possible. In recent experiments we irradiated capsule backlighters asymmetrically and measured the x-ray spectrum from multiple directions. We will present time-integrated spectra over the photon energy range of 2-13 keV and time-resolved spectra over the photon energy range of 2-3 keV. We will compare the spectra from different lines of sight to determine if the laser asymmetry results in an angular dependence in the x-ray emission.

  13. Spectral measurements of asymmetrically irradiated capsule backlighters

    SciTech Connect

    Keiter, P. A.; Drake, R. P.

    2016-09-09

    Capsule backlighters provide a quasi-continuum x-ray spectrum over a wide range of photon energies. Ideally one irradiates the capsule backlighter symmetrically, however, in complex experimental geometries, this is not always possible. In recent experiments we irradiated capsule backlighters asymmetrically and measured the x-ray spectrum from multiple directions. We will present time-integrated spectra over the photon energy range of ~2-13 keV and time-resolved spectra over the photon energy range of ~2-3 keV. Lastly, we will compare the spectra from different lines of sight to determine if the laser asymmetry results in an angular dependence in the x-ray emission.

  14. A Monoclonal Antibody to Cryptococcus neoformans Glucuronoxylomannan Manifests Hydrolytic Activity for Both Peptides and Polysaccharides.

    PubMed

    Bowen, Anthony; Wear, Maggie P; Cordero, Radames J B; Oscarson, Stefan; Casadevall, Arturo

    2017-01-13

    Studies in the 1980s first showed that some natural antibodies were "catalytic" and able to hydrolyze peptide or phosphodiester bonds in antigens. Many naturally occurring catalytic antibodies have since been isolated from human sera and associated with positive and negative outcomes in autoimmune disease and infection. The function and prevalence of these antibodies, however, remain unclear. A previous study suggested that the 18B7 monoclonal antibody against glucuronoxylomannan (GXM), the major component of the Cryptococcus neoformans polysaccharide capsule, hydrolyzed a peptide antigen mimetic. Using mass spectrometry and Förster resonance energy transfer techniques, we confirm and characterize the hydrolytic activity of 18B7 against peptide mimetics and show that 18B7 is able to hydrolyze an oligosaccharide substrate, providing the first example of a naturally occurring catalytic antibody for polysaccharides. Additionally, we show that the catalytic 18B7 antibody increases release of capsular polysaccharide from fungal cells. A serine protease inhibitor blocked peptide and oligosaccharide hydrolysis by 18B7, and a putative serine protease-like active site was identified in the light chain variable region of the antibody. An algorithm was developed to detect similar sites present in unique antibody structures in the Protein Data Bank. The putative site was found in 14 of 63 (22.2%) catalytic antibody structures and 119 of 1602 (7.4%) antibodies with no annotation of catalytic activity. The ability of many antibodies to cleave antigen, albeit slowly, supports the notion that this activity is an important immunoglobulin function in host defense. The discovery of GXM hydrolytic activity suggests new therapeutic possibilities for polysaccharide-binding antibodies.

  15. Water Landing Characteristics of a Reentry Capsule

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Experimental and theoretical investigations have been made to determine the water-landing characteristics of a conical-shaped reentry capsule having a segment of a sphere as the bottom. For the experimental portion of the investigation, a 1/12-scale model capsule and a full-scale capsule were tested for nominal flight paths of 65 deg and 90 deg (vertical), a range of contact attitudes from -30 deg to 30 deg, and a full-scale vertical velocity of 30 feet per second at contact. Accelerations were measured by accelerometers installed at the centers of gravity of the model and full-scale capsules. For the model test the accelerations were measured along the X-axis (roll) and Z-axis (yaw) and for the full-scale test they were measured along the X-axis (roll), Y-axis (pitch), and Z-axis (yaw). Motions and displacements of the capsules that occurred after contact were determined from high-speed motion pictures. The theoretical investigation was conducted to determine the accelerations that might occur along the X-axis when the capsule contacted the water from a 90 deg flight path at a 0 deg attitude. Assuming a rigid body, computations were made from equations obtained by utilizing the principle of the conservation of momentum. The agreement among data obtained from the model test, the full-scale test, and the theory was very good. The accelerations along the X-axis, for a vertical flight path and 0 deg attitude, were in the order of 40g. For a 65 deg flight path and 0 deg attitude, the accelerations along the X-axis were in the order of 50g. Changes in contact attitude, in either the positive or negative direction from 0 deg attitude, considerably reduced the magnitude of the accelerations measured along the X-axis. Accelerations measured along the Y- and Z-axes were relatively small at all test conditions.

  16. Video capsule endoscopy in inflammatory bowel disease

    PubMed Central

    Collins, Paul D

    2016-01-01

    Video capsule endoscopy (VCE) has evolved to become an important tool for the non-invasive examination of the small bowel, which hitherto had been relatively inaccessible to direct visualisation. VCE has been shown to play a role in monitoring the activity of small bowel Crohn’s disease and can be used to assess the response to anti-inflammatory treatment in Crohn’s disease. For those patients with Crohn’s disease who have undergone an intestinal resection, VCE has been assessed as a tool to detect post-operative recurrence. VCE may also aid in the reclassification of patients with a diagnosis of Inflammatory Bowel Disease Unclassified to Crohn’s disease. The evolution of colon capsule endoscopy (CCE) has expanded the application of this technology further. The use of CCE to assess the activity of ulcerative colitis has been described. This advance in capsule technology has also fuelled interest in its potential role as a minimally invasive tool to assess the whole of GI tract opening the possibility of its use for the panenteric assessment of Crohn’s disease. VCE is a safe procedure. However, the risk of a retained capsule is higher in patients with suspected or confirmed Crohn’s disease compared with patients having VCE examination for other indications. A retained video capsule is rare after successful passage of a patency capsule which may be utilised to pre-screen patients undergoing VCE. This paper describes the use of VCE in the assessment of inflammatory bowel disease. PMID:27499830

  17. Earthworm symbiont Verminephrobacter eiseniae mediates natural transformation within host egg capsules using type IV pili

    PubMed Central

    Davidson, Seana K.; Dulla, Glenn F.; Go, Ruth A.; Stahl, David A.; Pinel, Nicolás

    2014-01-01

    The dense microbial communities commonly associated with plants and animals should offer many opportunities for horizontal gene transfer through described mechanisms of DNA exchange including natural transformation (NT). However, studies of the significance of NT have focused primarily on pathogens. The study presented here demonstrates highly efficient DNA exchange by NT in a common symbiont of earthworms. The obligate bacterial symbiont Verminephrobacter eiseniae is a member of a microbial consortium of the earthworm Eisenia fetida that is transmitted into the egg capsules to colonize the embryonic worms. In the study presented here, by testing for transformants under different conditions in culture, we demonstrate that V. eiseniae can incorporate free DNA from the environment, that competency is regulated by environmental factors, and that it is sequence specific. Mutations in the type IV pili of V. eiseniae resulted in loss of DNA uptake, implicating the type IV pilus (TFP) apparatus in DNA uptake. Furthermore, injection of DNA carrying antibiotic-resistance genes into egg capsules resulted in transformants within the capsule, demonstrating the relevance of DNA uptake within the earthworm system. The ability to take up species-specific DNA from the environment may explain the maintenance of the relatively large, intact genome of this long-associated obligate symbiont, and provides a mechanism for acquisition of foreign genes within the earthworm system. PMID:25400622

  18. Polysaccharide-based Nanoparticles for Gene Delivery.

    PubMed

    Huh, Myung Sook; Lee, Eun Jung; Koo, Heebeom; Yhee, Ji Young; Oh, Keun Sang; Son, Sohee; Lee, Sojin; Kim, Sun Hwa; Kwon, Ick Chan; Kim, Kwangmeyung

    2017-04-01

    Nanoparticles based on nanotechnology and biotechnology have emerged as efficient carriers for various biopharmaceutical agents including proteins and genes. In particular, polysaccharides have attracted interest of many researchers in the drug delivery field due to their advantages such as biocompatibility, biodegradability, low toxicity, and ease of modification. A number of polysaccharides including chitosan, hyaluronic acid, and dextran, and their derivatives have been widely used as polymeric backbones for the formation of nanoparticles, which can be provided as valuable gene delivery carriers. In this review, we introduce the chemical and physical natures of different polysaccharides particularly used in biomedical applications, and then discuss recent progress in the development of polysaccharide-based nanoparticles for gene delivery.

  19. NMR analysis of compositional heterogeneity in polysaccharides

    USDA-ARS?s Scientific Manuscript database

    Many copolysaccharides are compositionally heterogeneous, and the composition determined by the usual analytical or spectroscopic methods provides only an average value. For some polysaccharides, the NMR data contain copolymer sequence information, such as diad, triad, and tetrad sequence intensiti...

  20. Interaction between gut immunity and polysaccharides.

    PubMed

    Huang, Xiaojun; Nie, Shaoping; Xie, Mingyong

    2017-09-22

    The human gut is colonized with a vast and diverse microbial ecosystem, and these bacteria play fundamental roles in the well being of our bodies. Gut-associated lymphoid tissues, the largest mucosal immune system, should never be overlooked for their profound effect in maintaining the host immunity. Therefore, we discussed the relationship between gut immunity and host health, primarily from two aspects: the homeostasis of gut microbiota, and the function of gut-associated lymphoid tissues. Polysaccharides, widely concerned as bioactive macromolecules in recent centuries, have been proved to benefit the intestinal health. Dietary polysaccharides can improve the ratio of probiotics, regulate the intestinal microenvironment like decreasing the gut pH, and stimulate the macrophages or lymphocytes in gut tissues to fight against diseases like cancer. Based on various experimental and clinical evidence, the impacts of dietary polysaccharides on intestinal health are summarized, in order to reveal the possible immunomodulatory mechanisms of polysaccharides.

  1. Multicomponent, hydrogen-bonded cylindrical capsules.

    PubMed

    Ajami, Dariush; Rebek, Julius

    2009-09-04

    Self-assembled, hydrogen-bonded capsules emerge from synthetic resorcinarene-derived cavitands and soluble glycolurils when appropriate guest molecules are present. The assembly consists of 2 cavitands, 4 glycolurils and guest(s), and the arrangement of glycolurils leads to a chiral structure. The capsule features a space of approximately 620 A(3) and accommodates narrow guests such as n-alkanes from C(14) to C(19), or other molecules (e.g., capsaicin) and combinations of molecules of up to approximately 22 A in length (e.g., two p-methylstyrene molecules). Positions of encapsulated nuclei can be predicted from NMR chemical shifts, with intense shielding of deltaDelta = -5 ppm near the resorcinarene ends and mild deshielding of +0.5 to 1 ppm near the glycolurils at the capsule's center. Computational methods using nucleus independent chemical shifts (NICS) were used to map the induced magnetic shielding/deshielding for the inner space of the cavity. The asymmetric arrangement of the spacers creates a chiral steric and magnetic environment in the capsule and the geminal hydrogen atoms of encapsulated alkanes show diastereotopic proton signals. The two enantiomers interconvert (racemize) through an achiral intermediate involving a slight rotation of the spacers and lengthening of the cavity. Accordingly, longer, compressed alkanes accelerate the racemization by applying pressure from the inside on the capsule's ends. Guests that place hydrogen bond donors and acceptors near the glycolurils in the middle (e.g., p-isopropylbenzyl alcohol) also accelerate the racemization by facilitating the rotation of the glycolurils. Slow tumbling of guest on the NMR time scale inside the capsule leads to social isomerism of para-disubstituted benzenes such as p-methylstyrene. Flexible guests such as hexane tumble inside the cavity with an activation barrier of DeltaG(++) =16.2 kcal/mol. The middle of the extended capsule is narrow, but still accommodates phenyl groups such as those

  2. Generic omeprazole delayed-release capsules: in vitro performance evaluations.

    PubMed

    Moore, Terry; Smith, Anjanette; Ye, Wei; Toler, Duckhee Y; Westenberger, Benjamin J; Lionberger, Robert; Raw, Andre; Yu, Lawrence; Buhse, Lucinda F

    2009-08-01

    After the patent on omeprazole delayed-release capsules expired, Food and Drug Administration (FDA) approved several generic omeprazole delayed-release capsule applications. FDA has received some complaints concerning a lack of therapeutic effect of the generic omeprazole delayed-release capsules. To investigate the quality of five different marketed generic omeprazole delayed-release capsules. The dissolution characteristics of these generic omeprazole delayed-release capsules were determined according to the United States Pharmacopeia (USP). Additional dissolution studies under simulated in vivo physiological conditions were also conducted to determine whether generic omeprazole capsules would perform similarly under these conditions. The experimental data show that all the generic omeprazole delayed-release capsules met the USP standards. The in vitro dissolution of generic drugs is similar to that of the brand omeprazole product. There is no scientific evidence to support the claims that the generic omeprazole delayed-release capsules perform differently from the brand omeprazole product in vitro.

  3. Monoclonal antibodies against plant cell wall polysaccharides

    SciTech Connect

    Hahn, M.G.; Bucheli, E.; Darvill, A.; Albersheim, P. )

    1989-04-01

    Monoclonal antibodies (McAbs) are useful tools to probe the structure of plant cell wall polysaccharides and to localize these polysaccharides in plant cells and tissues. Murine McAbs were generated against the pectic polysaccharide, rhamnogalacturonan I (RG-I), isolated from suspension-cultured sycamore cells. The McAbs that were obtained were grouped into three classes based upon their reactivities with a variety of plant polysaccharides and membrane glycoproteins. Eleven McAbs (Class I) recognize epitope(s) that appear to be immunodominant and are found in RG-I from sycamore and maize, citrus pectin, polygalacturonic acid, and membrane glycoproteins from suspension-cultured cells of sycamore, maize, tobacco, parsley, and soybean. A second group of five McAbs (Class II) recognize epitope(s) present in sycamore RG-I, but do not bind to any of the other polysaccharides or glycoproteins recognized by Class I. Lastly, one McAb (Class III) reacts with sycamore RG-I, sycamore and tamarind xyloglucan, and sycamore and rice glucuronoarabinoxylan, but does not bind to maize RG-I, polygalacturonic acid or the plant membrane glycoproteins recognized by Class I. McAbs in Classes II and III are likely to be useful in studies of the structure, biosynthesis and localization of plant cell wall polysaccharides.

  4. Tts, a processive beta-glucosyltransferase of Streptococcus pneumoniae, directs the synthesis of the branched type 37 capsular polysaccharide in Pneumococcus and other gram-positive species.

    PubMed

    Llull, D; Garcia, E; Lopez, R

    2001-06-15

    The type 37 capsule of Streptococcus pneumoniae is a homopolysaccharide built up from repeating units of [beta-d-Glcp-(1-->2)]-beta-d-Glcp-(1-->3). The elements governing the expression of the tts gene, coding for the glucosyltransferase involved in the synthesis of the type 37 pneumococcal capsular polysaccharide, have been studied. Primer extension analysis and functional tests demonstrated the presence of four new transcriptional start points upstream of the previously reported tts promoter (ttsp). Most interesting, three of these transcriptional start points are located in a RUP element thought to be involved in recombinational events (Oggioni, M. R., and Claverys, J. P. (1999) Microbiology 145, 2647-2653). Transformation experiments using either a recombinant plasmid containing the whole transcriptional unit of tts or chromosomal DNA from a type 37 pneumococcus showed that tts is the only gene required to drive the biosynthesis of a type 37 capsule in S. pneumoniae and other Gram-positive bacteria, namely Streptococcus oralis, Streptococcus gordonii, and Bacillus subtilis. The Tts synthase was overproduced in S. pneumoniae and purified as a membrane-associated enzyme. These membrane preparations used UDP-Glc as substrate to catalyze the synthesis of a high molecular weight polysaccharide immunologically identical to the type 37 capsule. In addition, UDP-Gal was also a substrate to produce type 37 polysaccharide since a strong UDP-Glc-4'-epimerase activity is associated to the membrane fraction of S. pneumoniae. These results indicated that Tts has a dual biochemical activity that leads to the synthesis of the branched type 37 polysaccharide.

  5. 50 CFR 622.493 - Landing Caribbean queen conch intact.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... conch intact. (a) A Caribbean queen conch in or from the Caribbean EEZ must be maintained with meat and shell intact. (b) The operator of a vessel that fishes in the EEZ is responsible for ensuring...

  6. 50 CFR 622.493 - Landing Caribbean queen conch intact.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... conch intact. (a) A Caribbean queen conch in or from the Caribbean EEZ must be maintained with meat and shell intact. (b) The operator of a vessel that fishes in the EEZ is responsible for ensuring...

  7. How can we conserve intact tropical peatlands?

    NASA Astrophysics Data System (ADS)

    Lawson, Ian; Roucoux, Katherine

    2017-04-01

    The scientific community has, for more than three decades, been expressing increasing alarm about the fate of peatlands in parts of Indonesia and Malaysia, where extensive land-use conversion and drainage for rice and oil palm have greatly compromised peatland hydrology, ecology, biological richness, and carbon storage. The discourse in the literature on these peatlands is now moving on from attempts to preserve the last remaining fragments of peat-swamp forest, towards discussion of how best to restore damaged ecosystems, and whether it is possible to manage plantations more 'sustainably'. It is becoming increasingly clear, however, that peatlands occur quite widely in other parts of the lowland tropics, including parts of Amazonia and the Congo Basin, and many of these peatlands can reasonably be described as 'intact': although few if any parts of the tropics are totally unaffected by human actions, the hydrology and functional ecology of these systems appear to be close to a 'natural' state. The question then arises as to what should be done with the knowledge of their existence. Here we analyse the arguments in favour of protecting intact peatlands, and the potential conflicts with other priorities such as economic development and social justice. We evaluate alternative mechanisms for protecting intact peatlands, focusing on the particular issues raised by peatlands as opposed to other kinds of tropical ecosystem. We identify ways in which natural science agendas can help to inform these arguments, using our own contributions in palaeoecology and carbon mapping as examples. Finally, we argue for a radical reconsideration of research agendas in tropical peatlands, highlighting the potential contribution of methodologies borrowed from the social sciences and humanities.

  8. Calcium Signaling in Intact Dorsal Root Ganglia

    PubMed Central

    Gemes, Geza; Rigaud, Marcel; Koopmeiners, Andrew S.; Poroli, Mark J.; Zoga, Vasiliki; Hogan, Quinn H.

    2013-01-01

    Background Ca2+ is the dominant second messenger in primary sensory neurons. In addition, disrupted Ca2+ signaling is a prominent feature in pain models involving peripheral nerve injury. Standard cytoplasmic Ca2+ recording techniques use high K+ or field stimulation and dissociated neurons. To compare findings in intact dorsal root ganglia, we used a method of simultaneous electrophysiologic and microfluorimetric recording. Methods Dissociated neurons were loaded by bath-applied Fura-2-AM and subjected to field stimulation. Alternatively, we adapted a technique in which neuronal somata of intact ganglia were loaded with Fura-2 through an intracellular microelectrode that provided simultaneous membrane potential recording during activation by action potentials (APs) conducted from attached dorsal roots. Results Field stimulation at levels necessary to activate neurons generated bath pH changes through electrolysis and failed to predictably drive neurons with AP trains. In the intact ganglion technique, single APs produced measurable Ca2+ transients that were fourfold larger in presumed nociceptive C-type neurons than in nonnociceptive Aβ-type neurons. Unitary Ca2+ transients summated during AP trains, forming transients with amplitudes that were highly dependent on stimulation frequency. Each neuron was tuned to a preferred frequency at which transient amplitude was maximal. Transients predominantly exhibited monoexponential recovery and had sustained plateaus during recovery only with trains of more than 100 APs. Nerve injury decreased Ca2+ transients in C-type neurons, but increased transients in Aβ-type neurons. Conclusions Refined observation of Ca2+ signaling is possible through natural activation by conducted APs in undissociated sensory neurons and reveals features distinct to neuronal types and injury state. PMID:20526180

  9. Gene content and diversity of the loci encoding biosynthesis of capsular polysaccharides of the 15 serovar reference strains of Haemophilus parasuis.

    PubMed

    Howell, Kate J; Weinert, Lucy A; Luan, Shi-Lu; Peters, Sarah E; Chaudhuri, Roy R; Harris, David; Angen, Oystein; Aragon, Virginia; Parkhill, Julian; Langford, Paul R; Rycroft, Andrew N; Wren, Brendan W; Tucker, Alexander W; Maskell, Duncan J

    2013-09-01

    Haemophilus parasuis is the causative agent of Glässer's disease, a systemic disease of pigs, and is also associated with pneumonia. H. parasuis can be classified into 15 different serovars. Here we report, from the 15 serotyping reference strains, the DNA sequences of the loci containing genes for the biosynthesis of the group 1 capsular polysaccharides, which are potential virulence factors of this bacterium. We contend that these loci contain genes for polysaccharide capsule structures, and not a lipopolysaccharide O antigen, supported by the fact that they contain genes such as wza, wzb, and wzc, which are associated with the export of polysaccharide capsules in the current capsule classification system. A conserved region at the 3' end of the locus, containing the wza, ptp, wzs, and iscR genes, is consistent with the characteristic export region 1 of the model group 1 capsule locus. A potential serovar-specific region (region 2) has been found by comparing the predicted coding sequences (CDSs) in all 15 loci for synteny and homology. The region is unique to each reference strain with the exception of those in serovars 5 and 12, which are identical in terms of gene content. The identification and characterization of this locus among the 15 serovars is the first step in understanding the genetic, molecular, and structural bases of serovar specificity in this poorly studied but important pathogen and opens up the possibility of developing an improved molecular serotyping system, which would greatly assist diagnosis and control of Glässer's disease.

  10. Gene Content and Diversity of the Loci Encoding Biosynthesis of Capsular Polysaccharides of the 15 Serovar Reference Strains of Haemophilus parasuis

    PubMed Central

    Weinert, Lucy A.; Luan, Shi-Lu; Peters, Sarah E.; Chaudhuri, Roy R.; Harris, David; Angen, Øystein; Aragon, Virginia; Parkhill, Julian; Langford, Paul R.; Rycroft, Andrew N.; Wren, Brendan W.; Tucker, Alexander W.; Maskell, Duncan J.

    2013-01-01

    Haemophilus parasuis is the causative agent of Glässer's disease, a systemic disease of pigs, and is also associated with pneumonia. H. parasuis can be classified into 15 different serovars. Here we report, from the 15 serotyping reference strains, the DNA sequences of the loci containing genes for the biosynthesis of the group 1 capsular polysaccharides, which are potential virulence factors of this bacterium. We contend that these loci contain genes for polysaccharide capsule structures, and not a lipopolysaccharide O antigen, supported by the fact that they contain genes such as wza, wzb, and wzc, which are associated with the export of polysaccharide capsules in the current capsule classification system. A conserved region at the 3′ end of the locus, containing the wza, ptp, wzs, and iscR genes, is consistent with the characteristic export region 1 of the model group 1 capsule locus. A potential serovar-specific region (region 2) has been found by comparing the predicted coding sequences (CDSs) in all 15 loci for synteny and homology. The region is unique to each reference strain with the exception of those in serovars 5 and 12, which are identical in terms of gene content. The identification and characterization of this locus among the 15 serovars is the first step in understanding the genetic, molecular, and structural bases of serovar specificity in this poorly studied but important pathogen and opens up the possibility of developing an improved molecular serotyping system, which would greatly assist diagnosis and control of Glässer's disease. PMID:23873912

  11. Biodistribution of polymer hydrogel capsules for the delivery of therapeutics.

    PubMed

    Hinton, Tracey M; Monaghan, Paul; Green, Diane; Kooijmans, Sander A A; Shi, Shuning; Breheney, Kerry; Tizard, Mark; Nicolazzo, Joseph A; Zelikin, Alexander N; Wark, Kim

    2012-09-01

    A key phase in the development of intelligently designed nanoparticle delivery vehicles for new therapeutic agents is to gain an understanding of their interaction with tissues and cells. We report a series of in vitro and in vivo experiments aimed at tracking a potential delivery vehicle for therapeutic agents, including vaccine peptides and drugs derived from poly(methacrylic acid) hydrogel capsules in certain organs and cell types. For the in vitro studies, two immortal liver-derived cell lines (Huh7 and Hepa1-6) and primary cultures of mouse hepatocytes were incubated with Alexa 647 labelled fluorescent capsules to track their internalization and intracellular distribution by confocal microscopy. Capsules, 500nm in diameter, were taken up into the cells in a time-dependent manner in all three cell lines. Capsules were observed in plasma membrane-derived vesicles within the cells. After 24h a significant proportion of the capsules was observed in lysosomes. To understand the behaviour of the capsules in vivo, Alexa 488 labelled fluorescent capsules were intravenously injected into Sprague-Dawley rats and after 24h the fate of the capsules in a number of organs was determined by flow cytometry and confocal microscopy. By flow cytometry, the majority of the capsules were detected in the spleen whilst similar numbers were found in the lung and liver. By confocal microscopy, the majority of the capsules were found in the liver and spleen with significantly less capsules in the lung, heart and kidney. Colocalization of capsules with cell-type specific markers indicated that in lung, heart and kidney, the majority of the capsules were located in endothelial cells. In the spleen ~50% of the capsules were found in CD163-positive cells, whereas in the liver, almost all capsules were located in CD163-positive cells, indicating uptake by Kupffer cells. Electron microscopy confirmed the presence of capsules within Kupffer cells. Crown Copyright © 2012. Published by

  12. Sodium Absorption by Intact Sugar Beet Plants

    PubMed Central

    El-Sheikh, Adel M; Ulrich, Albert

    1971-01-01

    Sodium absorption by intact sugar beet plants (Beta vulgaris) was found to be mediated by at least two distinct mechanisms when uptake was studied over a wide range of Na and K concentrations. The first mechanism operates at low Na concentrations (<1 milliequivalent per liter); presence of K completely blocks this mechanism for Na. The second mechanism operates at high Na concentrations (>1 milliequivalent per liter), transporting Na as well as K; but apparently this mechanism is not active for Na absorption in young sugar beet plants up to the 10-leaf stage. PMID:16657872

  13. Carbohydrate-binding modules promote the enzymatic deconstruction of intact plant cell walls by targeting and proximity effects.

    PubMed

    Hervé, Cécile; Rogowski, Artur; Blake, Anthony W; Marcus, Susan E; Gilbert, Harry J; Knox, J Paul

    2010-08-24

    Cell wall degrading enzymes have a complex molecular architecture consisting of catalytic modules and noncatalytic carbohydrate-binding modules (CBMs). The function of CBMs in cell wall degrading processes is poorly understood. Here, we have evaluated the potential enzyme-targeting function of CBMs in the context of intact primary and secondary cell wall deconstruction. The capacity of a pectate lyase to degrade pectic homogalacturonan in primary cell walls was potentiated by cellulose-directed CBMs but not by xylan-directed CBMs. Conversely, the arabinofuranosidase-mediated removal of side chains from arabinoxylan in xylan-rich and cellulose-poor wheat grain endosperm cell walls was enhanced by a xylan-binding CBM but less so by a crystalline cellulose-specific module. The capacity of xylanases to degrade xylan in secondary cell walls was potentiated by both xylan- and cellulose-directed CBMs. These studies demonstrate that CBMs can potentiate the action of a cognate catalytic module toward polysaccharides in intact cell walls through the recognition of nonsubstrate polysaccharides. The targeting actions of CBMs therefore have strong proximity effects within cell wall structures, explaining why cellulose-directed CBMs are appended to many noncellulase cell wall hydrolases.

  14. 21 CFR 872.3110 - Dental amalgam capsule.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental amalgam capsule. 872.3110 Section 872.3110...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3110 Dental amalgam capsule. (a) Identification. A dental amalgam capsule is a container device in which silver alloy is intended to be mixed with...

  15. 21 CFR 520.580 - Dichlorophene and toluene capsules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Dichlorophene and toluene capsules. 520.580... Dichlorophene and toluene capsules. (a) Specifications. Each soft gelatin capsule contains 50 milligrams of dichlorophene and 60 milligrams of toluene or multiples thereof. (b) Sponsor. (1) For single dose only, see...

  16. 21 CFR 520.580 - Dichlorophene and toluene capsules.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Dichlorophene and toluene capsules. 520.580... Dichlorophene and toluene capsules. (a) Specifications. Each soft gelatin capsule contains 50 milligrams of dichlorophene and 60 milligrams of toluene or multiples thereof. (b) Sponsor. (1) For single dose only, see...

  17. 21 CFR 520.446 - Clindamycin capsules and tablets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... capsules and tablets. (a) Specifications(1) Each capsule contains the equivalent of 25, 75, 150, or 300 milligrams (mg) clindamycin as the hydrochloride salt. (2) Each tablet contains the equivalent of 25, 75, or 150 mg clindamycin as the hydrochloride salt. (3) Each capsule contains the equivalent of 25, 75, or...

  18. 21 CFR 520.1804 - Piperazine phosphate capsules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Piperazine phosphate capsules. 520.1804 Section... phosphate capsules. (a) Specifications. Each capsule contains 120, 300, or 600 milligrams of piperazine phosphate monohydrate. (b) Sponsor. See No. 051311 in § 510.600(c) of this chapter. (c) Conditions of use—(1...

  19. 21 CFR 520.1804 - Piperazine phosphate capsules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Piperazine phosphate capsules. 520.1804 Section... phosphate capsules. (a) Specifications. Each capsule contains 120, 300, or 600 milligrams of piperazine phosphate monohydrate. (b) Sponsor. See No. 051311 in § 510.600(c) of this chapter. (c) Conditions of use—(1...

  20. 21 CFR 520.1804 - Piperazine phosphate capsules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Piperazine phosphate capsules. 520.1804 Section... phosphate capsules. (a) Specifications. Each capsule contains 120, 300, or 600 milligrams of piperazine phosphate monohydrate. (b) Sponsor. See No. 051311 in § 510.600(c) of this chapter. (c) Conditions of use—(1...

  1. 21 CFR 520.1804 - Piperazine phosphate capsules.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Piperazine phosphate capsules. 520.1804 Section... phosphate capsules. (a) Specifications. Each capsule contains 120, 300, or 600 milligrams of piperazine phosphate monohydrate. (b) Sponsor. See No. 051311 in § 510.600(c) of this chapter. (c) Conditions of use—(1...

  2. 21 CFR 520.1804 - Piperazine phosphate capsules.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Piperazine phosphate capsules. 520.1804 Section... phosphate capsules. (a) Specifications. Each capsule contains 120, 300, or 600 milligrams of piperazine phosphate monohydrate. (b) Sponsor. See No. 051311 in § 510.600(c) of this chapter. (c) Conditions of use—(1...

  3. 21 CFR 520.608 - Dicloxacillin sodium monohydrate capsules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Dicloxacillin sodium monohydrate capsules. 520.608 Section 520.608 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Dicloxacillin sodium monohydrate capsules. (a) Specifications. Each capsule contains dicloxacillin...

  4. 21 CFR 520.260 - n-Butyl chloride capsules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false n-Butyl chloride capsules. 520.260 Section 520.260... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.260 n-Butyl chloride capsules. (a)(1) Specifications. n-Butyl chloride capsules, veterinary contain 272 milligrams or 816 milligrams...

  5. 21 CFR 520.622d - Diethylcarbamazine citrate capsules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Diethylcarbamazine citrate capsules. 520.622d... Diethylcarbamazine citrate capsules. (a) Specifications. Each capsule contains 12.5, 50, 200, or 400 milligrams (mg) diethylcarbamazine citrate. (b) Sponsor. See No. 011014 in § 510.600(c) of this chapter. (c) Conditions of use...

  6. Capsule endoscopy of the small bowel

    PubMed Central

    Ching, Hey-Long; Yung, Diana; Sidhu, Reena; Koulaouzidis, Anastasios

    2016-01-01

    Capsule endoscopy (CE) is a first line small bowel investigative modality which provides more sensitive mucosal imaging than comparators. It is a non-invasive, non-irradiating tool well tolerated by patients. The risk of retention of the capsule can be minimised by ensuring luminal patency using the Agile patency device. Research continues into how to minimise missed pathology and variability in the identification of pathology or interpretation of images. The consensus is that bowel preparation using laxatives improves visibility and diagnostic yield. Research includes the development of image recognition software, both to eliminate sequentially identical images to improve viewing speed and to select or enhance images likely to represent pathology. However, careful reading by experienced capsule endoscopists remains the benchmark. This should be performed at a speed comfortable to the viewer, probably at a maximum of 15 frames per second. Some prior experience of endoscopy appears to be helpful for novice capsule endoscopists and formal training on a hands-on training course seems to improve pathology recognition, for novices and for those with CE experience. PMID:27826572

  7. Design of Endoscopic Capsule With Multiple Cameras.

    PubMed

    Gu, Yingke; Xie, Xiang; Li, Guolin; Sun, Tianjia; Wang, Dan; Yin, Zheng; Zhang, Pengfei; Wang, Zhihua

    2015-08-01

    In order to reduce the miss rate of the wireless capsule endoscopy, in this paper, we propose a new system of the endoscopic capsule with multiple cameras. A master-slave architecture, including an efficient bus architecture and a four level clock management architecture, is applied for the Multiple Cameras Endoscopic Capsule (MCEC). For covering more area of the gastrointestinal tract wall with low power, multiple cameras with a smart image capture strategy, including movement sensitive control and camera selection, are used in the MCEC. To reduce the data transfer bandwidth and power consumption to prolong the MCEC's working life, a low complexity image compressor with PSNR 40.7 dB and compression rate 86% is implemented. A chipset is designed and implemented for the MCEC and a six cameras endoscopic capsule prototype is implemented by using the chipset. With the smart image capture strategy, the coverage rate of the MCEC prototype can achieve 98% and its power consumption is only about 7.1 mW.

  8. Capsule endoscopy in patients refusing conventional endoscopy

    PubMed Central

    Romero-Vázquez, Javier; Argüelles-Arias, Federico; García-Montes, Josefa Maria; Caunedo-Álvarez, Ángel; Pellicer-Bautista, Francisco Javier; Herrerías-Gutiérrez, Juan Manuel

    2014-01-01

    Capsule endoscopy is nowadays the diagnostic technique of choice in the study of small bowel pathologies, allowing the non-invasive study of the entire mucosa. This has led, together with new technical advances, to the creation of two new models (PillCam ESO and PillCam Colon) for the study of esophageal and colonic diseases. These two new capsules offer an interesting alternative to conventional endoscopy in the study of the upper and lower digestive tracts, because traditional endoscopy is often unpleasant and uncomfortable for the patient, can be painful, often requires moderate or deep sedation and is not without complications (hemorrhage, perforation, etc.). PillCam Colon is particularly important for its usefulness in the diagnosis of colonic polyps, and is a potentially useful tool in cases of incomplete colonoscopy or in colorectal cancer screening, even more when most patients are reluctant to undergo screening programs due to the said disadvantages of conventional colonoscopy. This article discusses the advantages of capsule endoscopy over conventional endoscopy, its current application possibilities and indications in routine clinical practice. In the various sections of the work, we assess the application of endoscopic capsule in different sections of the digestive tract (esophagus, stomach, and colon) and finally the potential role of panendoscopy with PillCam Colon. PMID:24966612

  9. Extended School Year. Information Capsule. Volume 0910

    ERIC Educational Resources Information Center

    Blazer, Christie

    2010-01-01

    Extended school years are being considered by districts around the country as educators search for new ways to raise student achievement. The addition of time to the school calendar is also supported by President Barack Obama, who recently stated that American students do not spend enough time in school. This Information Capsule addresses research…

  10. Reciprocal Teaching. Information Capsule. Volume 0609

    ERIC Educational Resources Information Center

    Blazer, Christie

    2007-01-01

    Reciprocal teaching is an instructional approach designed to increase students' reading comprehension at all grade levels and in all subject areas. Students are taught cognitive strategies that help them construct meaning from text and simultaneously monitor their reading comprehension. This Information Capsule summarizes reciprocal teaching's…

  11. Release of Boilerplate Mercury Capsule Sequence

    NASA Image and Video Library

    1958-12-16

    Photographed on: 12 16 58. -- L58-1083a caption: Sequenced pictures showing events from release of boilerplate Mercury capsule from C-130 airplane to opening of recovery parachute, December 1958. Photograph published in A New Dimension Wallops Island Flight Test Range: The First Fifteen Years by Joseph Shortal. A NASA publication, page 644.

  12. Wireless capsule endoscopy: Perspectives beyond gastrointestinal bleeding

    PubMed Central

    Redondo-Cerezo, Eduardo; Sánchez-Capilla, Antonio Damián; De La Torre-Rubio, Paloma; De Teresa, Javier

    2014-01-01

    Wireless capsule endoscopy (CE) is a technology developed for the endoscopic exploration of the small bowel. The first capsule model was approved by the Food and Drug Administration in 2001, and its first and essential indication was occult gastrointestinal (GI) bleeding. Over subsequent years, this technology has been refined to provide superior resolution, increased battery life, and capabilities to view different parts of the GI tract. Indeed, cases for which CE proved useful have increased significantly over the last few years, with new indications for the small bowel and technical improvements that have expanded its use to other parts of the GI tract, including the esophagus and colon. The main challenges in the development of CE are new devices with the ability to provide therapy, air inflation for a better vision of the small bowel, biopsy sampling systems attached to the capsule and the possibility to guide and move the capsule with an external motion control. In this article we review the current and new indications of CE, and the evolving technological changes shaping this technology, which has a promising potential in the coming future of gastroenterology. PMID:25400450

  13. Reduced scale National Ignition Facility capsule design

    NASA Astrophysics Data System (ADS)

    Dittrich, T. R.; Haan, S. W.; Marinak, M. M.; Pollaine, S. M.; McEachern, R.

    1998-10-01

    In this article we describe the design and simulated performance characteristics of an indirectly-driven inertial confinement fusion capsule which utilizes only 900 kJ of laser energy and 250 TW of laser power from the National Ignition Facility (NIF) [Paisner et al., Laser Focus World 30, 75 (1994)]. This intentional reduction in laser performance from the nominal NIF specifications of 1.8 MJ and 500 TW results in lowering the hohlraum x-ray drive temperature from 300 eV to 250 eV. These energy and radiation temperature reductions are believed to define a "lower bound" on the successful implosion of an ignition capsule. This reduced scale capsule has a beryllium ablator containing a radially varying copper dopant, and a cryogenic solid deuterium-tritium fuel layer surrounding a cavity filled with equilibrium vapor pressure gaseous deuterium and tritium. Two-dimensional simulations predict ignition and propagated burn from this capsule when either Rayleigh-Taylor instability or time-dependent drive asymmetry effects are included.

  14. Student Mobility. Information Capsule. Volume 0608

    ERIC Educational Resources Information Center

    Blazer, Christie

    2007-01-01

    Mobility, rather than stability, has become the norm for students in schools across the United States. The student mobility rate is now higher in the United States than in any other industrialized country. This Information Capsule discusses the reasons for student mobility and the characteristics of highly mobile students and families. Research…

  15. 33 CFR 157.22 - Intact stability requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Intact stability requirements... OIL IN BULK Design, Equipment, and Installation § 157.22 Intact stability requirements. All tank ships of 5,000 DWT and above contracted after December 3, 2001 must comply with the intact stability...

  16. 33 CFR 157.22 - Intact stability requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Intact stability requirements... OIL IN BULK Design, Equipment, and Installation § 157.22 Intact stability requirements. All tank ships of 5,000 DWT and above contracted after December 3, 2001 must comply with the intact stability...

  17. 33 CFR 157.22 - Intact stability requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Intact stability requirements... OIL IN BULK Design, Equipment, and Installation § 157.22 Intact stability requirements. All tank ships of 5,000 DWT and above contracted after December 3, 2001 must comply with the intact stability...

  18. 33 CFR 157.22 - Intact stability requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Intact stability requirements... OIL IN BULK Design, Equipment, and Installation § 157.22 Intact stability requirements. All tank ships of 5,000 DWT and above contracted after December 3, 2001 must comply with the intact stability...

  19. 33 CFR 157.22 - Intact stability requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Intact stability requirements... OIL IN BULK Design, Equipment, and Installation § 157.22 Intact stability requirements. All tank ships of 5,000 DWT and above contracted after December 3, 2001 must comply with the intact stability...

  20. Rapid isolation of intact chloroplasts from spinach leaves.

    PubMed

    Joly, David; Carpentier, Robert

    2011-01-01

    In this chapter, a rapid method to isolate intact chloroplasts from spinach leaves is described. Intact chloroplasts are isolated using two short centrifugation steps and avoiding the use of percoll gradient. Intactness of chloroplast is evaluated by the inability of potassium ferricyanide to enter inside the chloroplasts and to act as an electron acceptor for photosystem II.

  1. Phosphorylcholine stimulates capsule formation of phosphate-limited mucoid Pseudomonas aeruginosa.

    PubMed Central

    Krieg, D P; Bass, J A; Mattingly, S J

    1988-01-01

    Production of both alginic acid and lipopolysaccharide by a mucoid strain of Pseudomonas aeruginosa, SRM-3, was studied in a chemostat system during growth under nutrient-limiting conditions chosen to reflect the chronic growth conditions in the lungs of cystic fibrosis patients. Since mucoid strains have been shown to elaborate extracellular proteases and phospholipase C, nitrogen and phosphate limitation were selected for analysis. A modified alginate-promoting medium containing either 1 mM glutamate or 0.05 mM K2HPO4 as limiting nutrient and doubling times of 1.6 to 15.7 h were used. Under nitrogen limitation, strain SRM-3 produced 1.4 mg of uronic acid per mg (dry weight) of cells at all doubling times studied. However, phosphate limitation resulted in the synthesis of only 0.4 mg of uronic acid per mg (dry weight) of cells. The role of phosphate in alginic acid polysaccharide production was further investigated by using phosphorylcholine, a product of phospholipase C activity on phosphatidylcholine, the major lung surfactant. No only were mucoid cells capable of utilizing phosphorylcholine for growth, but a highly specific interaction occurred among phosphorylcholine, alginate, and whole cells, resulting in greatly enhanced culture viscosity. Electron micrographs showed the gradual formation of a capsule during growth on phosphorylcholine, indicating that the mucoid strain has the ability to utilize surfactant not only as a nutrient source but also for constructing a capsule with greatly enhanced adhesive properties. Images PMID:3126146

  2. Mutation in fucose synthesis gene of Klebsiella pneumoniae affects capsule composition and virulence in mice.

    PubMed

    Pan, Po-Chang; Chen, Hui-Wen; Wu, Po-Kuan; Wu, Yu-Yang; Lin, Chun-Hung; Wu, June H

    2011-02-01

    The emerging pathogenicity of Klebsiella pneumoniae (KP) is evident by the increasing number of clinical cases of liver abscess (LA) due to KP infection. A unique property of KP is its thick mucoid capsule. The bacterial capsule has been found to contain fucose in KP strains causing LA but not in those causing urinary tract infections. The products of the gmd and wcaG genes are responsible for converting mannose to fucose in KP. A KP strain, KpL1, which is known to have a high death rate in infected mice, was mutated by inserting an apramycin-resistance gene into the gmd. The mutant expressed genes upstream and downstream of gmd, but not gmd itself, as determined by reverse transcriptase polymerase chain reaction. The DNA mapping confirmed the disruption of the gmd gene. This mutant decreased its ability to kill infected mice and showed decreased virulence in infected HepG2 cells. Compared with wild-type KpL1, the gmd mutant lost fucose in capsular polysaccharides, increased biofilm formation and interacted more readily with macrophages. The mutant displayed morphological changes with long filament forms and less uniform sizes. The mutation also converted the serotype from K1 of wild-type to K2 and weak K3. The results indicate that disruption of the fucose synthesis gene affected the pathophysiology of this bacterium and may be related to the virulence of this KpL1 strain.

  3. Cryptococcus neoformans Intracellular Proliferation and Capsule Size Determines Early Macrophage Control of Infection.

    PubMed

    Bojarczuk, Aleksandra; Miller, Katie A; Hotham, Richard; Lewis, Amy; Ogryzko, Nikolay V; Kamuyango, Alfred A; Frost, Helen; Gibson, Rory H; Stillman, Eleanor; May, Robin C; Renshaw, Stephen A; Johnston, Simon A

    2016-02-18

    Cryptococcus neoformans is a significant fungal pathogen of immunocompromised patients. Many questions remain regarding the function of macrophages in normal clearance of cryptococcal infection and the defects present in uncontrolled cryptococcosis. Two current limitations are: 1) The difficulties in interpreting studies using isolated macrophages in the context of the progression of infection, and 2) The use of high resolution imaging in understanding immune cell behavior during animal infection. Here we describe a high-content imaging method in a zebrafish model of cryptococcosis that permits the detailed analysis of macrophage interactions with C. neoformans during infection. Using this approach we demonstrate that, while macrophages are critical for control of C. neoformans, a failure of macrophage response is not the limiting defect in fatal infections. We find phagocytosis is restrained very early in infection and that increases in cryptococcal number are driven by intracellular proliferation. We show that macrophages preferentially phagocytose cryptococci with smaller polysaccharide capsules and that capsule size is greatly increased over twenty-four hours of infection, a change that is sufficient to severely limit further phagocytosis. Thus, high-content imaging of cryptococcal infection in vivo demonstrates how very early interactions between macrophages and cryptococci are critical in the outcome of cryptococcosis.

  4. Water Landing Characteristics of a Reentry Capsule

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Water Landing Characteristics of a Reentry Capsule. Experimental and theoretical investigations have been made to determine the water-landing characteristics of a conical-shaped reentry capsule having a segment of a sphere as the bottom. For the experimental portion of the investigation, a 1/12-scale model capsule and a full-scale capsule were tested for nominal flight paths of 65 deg and 90 deg (vertical), a range of contact attitudes from -30 deg to 30 deg, and a full-scale vertical velocity of 30 feet per second at contact. Accelerations were measured by accelerometers installed at the centers of gravity of the model and full-scale capsules. For the model test the accelerations were measured along the X-axis (roll) and Z-axis (yaw) and for the full-scale test they were measured along the X-axis (roll), Y-axis (pitch), and Z-axis (yaw). Motions and displacements of the capsules that occurred after contact were determined from high-speed motion pictures. The theoretical investigation was conducted to determine the accelerations that might occur along the X-axis when the capsule contacted the water from a 90 deg flight path at a 0 deg attitude. Assuming a rigid body, computations were made from equations obtained by utilizing the principle of the conservation of momentum. The agreement among data obtained from the model test, the full-scale test, and the theory was very good. The accelerations along the X-axis, for a vertical flight path and 0 deg attitude, were in the order of 40g. For a 65 deg flight path and 0 deg attitude, the accelerations along the X-axis were in the order of 50g. Changes in contact attitude, in either the positive or negative direction from 0 deg attitude, considerably reduced the magnitude of the accelerations measured along the X-axis. Accelerations measured along the Y- and Z-axes were relatively small at all test conditions. [Entire movie available on DVD from CASI as Doc ID 20070030955. Contact help@sti.nasa.gov

  5. In vivo anti-radiation activities of the Ulva pertusa polysaccharides and polysaccharide-iron(III) complex.

    PubMed

    Shi, Jinming; Cheng, Cuilin; Zhao, Haitian; Jing, Jing; Gong, Ning; Lu, Weihong

    2013-09-01

    Polysaccharides with different molecular weights were extracted from Ulva pertusa and fractionated by ultrafiltration. Iron(III) complex of the low molecular-weight U. pertusa polysaccharides were synthesized. Atomic absorption spectrum showed that the iron content of iron(III)-polysaccharide complex was 27.4%. The comparison between U. pertusa polysaccharides and their iron(III) complex showed that iron chelating altered the structural characteristics of the polysaccharides. The bioactivity analysis showed that polysaccharide with low molecular weight was more effective than polysaccharide with high molecular weight in protecting mice from radiation induced damages on bone marrow cells and immune system. Results also proved that the anti-radiation and anti-oxidative activity of iron(III) complex of low molecular-weight polysaccharides were not less than that of low molecular-weight polysaccharides.

  6. Safety of femtosecond laser-assisted cataract surgery: assessment of aqueous humour and lens capsule.

    PubMed

    Yu, A-Yong; Lin, Cai-Xia; Wang, Qin-Mei; Zheng, Mei-Qing; Qin, Xiao-Yi

    2016-11-01

    To investigate the effect of femtosecond laser-assisted cataract surgery (FLACS) on aqueous humour and lens capsule. This prospective randomized comparative study enrolled 19 eyes that underwent FLACS as the trial group and 20 eyes that underwent conventional phacoemulsification as the control group. The femtosecond laser platform (LLS-fs 3D; LensAR, Orlando, FL, USA) was used to generate capsulotomy (laser energy 8 μJ) and lens fragmentation (laser energy 10 μJ). Morphology of the cutting edge and cells of anterior capsule was assessed by light microscopy. The proteins in the aqueous humour were identified by mass spectrometry (Ultraflex III TOF/TOF; Bruker Dalton, Bremen, Germany). Electrolyte in the aqueous humour was detected by a chemistry analyzer (Aeroset Clinical Chemistry Analyzer; Abbott Laboratories, Abbott Park, IL, USA). The cutting edge of anterior capsule was saw-tooth-shaped under magnification of 200× and 400× in the trial group, while it was smooth in the control group. Intact cells were found in the boundary area next to the cutting edge of anterior capsule in both groups. β-Crystallin B1, γ-crystallin S and transferrin were detected in the aqueous humour in the trial group. The concentrations of K(+) , Na(+) and Cl(-) in the aqueous humour in the trial group differed significantly from those in the control group (p = 0.02, 0.03 and 0.04, respectively). Femtosecond laser-assisted cataract surgery (FLACS) causes release of transferrin and crystallin from lens to aqueous humour and results in significant changes in the concentrations of K(+) , Na(+) and Cl(-) in aqueous humour. However, these changes due to FLACS have no clinical significance or toxicity. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  7. Structural analysis of cell wall polysaccharides using PACE

    SciTech Connect

    Mortimer, Jennifer C.

    2017-01-01

    The plant cell wall is composed of many complex polysaccharides. The composition and structure of the polysaccharides affect various cell properties including cell shape, cell function and cell adhesion. Many techniques to characterize polysaccharide structure are complicated, requiring expensive equipment and specialized operators e.g. NMR, MALDI-MS. PACE (Polysaccharide Analysis using Carbohydrate gel Electrophoresis) uses a simple, rapid technique to analyze polysaccharide quantity and structure (Goubet et al. 2002). Whilst the method here describes xylan analysis, it can be applied (by use of the appropriate glycosyl hydrolase) to any cell wall polysaccharide.

  8. Preparation Methods and Antioxidant Activities of Polysaccharides and Their Derivatives.

    PubMed

    Mei, Xinya; Yi, Chengkun; Huang, Gangliang

    2017-01-01

    In recent years, the antioxidant effects of polysaccharides have become a hot spot in the field of polysaccharide research. Herein, the action mechanisms of polysaccharide antioxidation and scavenging free radicals were analyzed. The research progresses on the preparation methods and antioxidant properties of polysaccharides and their derivatives were summarized. Investigating the antioxidant activities of polysaccharides and their derivatives can find useful polysaccharides and their derivatives, which have great potential as natural antioxidants used in functional foods or medicines. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  9. RNA aptamer delivery through intact human skin.

    PubMed

    Lenn, Jon D; Neil, Jessica; Donahue, Christine; Demock, Kellie; Tibbetts, Caitlin Vestal; Cote-Sierra, Javier; Smith, Susan H; Rubenstein, David; Therrien, Jean-Philippe; Pendergrast, P Shannon; Killough, Jason; Brown, Marc B; Williams, Adrian C

    2017-09-20

    It is generally recognised that only relatively small molecular weight (typically < ∼500 Da) drugs can effectively permeate through intact stratum corneum. Here, we challenge this orthodoxy using a 62-nucleotide (MW=20,395) RNA-based aptamer, highly specific to the human IL-23 cytokine, with picomolar activity. Results demonstrate penetration of the aptamer into freshly excised human skin using two different fluorescent labels. A dual hybridisation assay quantified aptamer from the epidermis and dermis giving levels far exceeding the cellular IC50 values (> 100,000-fold) and aptamer integrity was confirmed using an oligonucleotide precipitation assay. A Th17 response was stimulated in freshly excised human skin resulting in significantly upregulated IL-17f, and 22; topical application of the IL-23 aptamer decreased both IL-17f and IL-22 by approximately 45% but did not result in significant changes to IL-23 mRNA levels, confirming that the aptamer did not globally suppress mRNA levels. This study demonstrates that very large molecular weight RNA aptamers can permeate across the intact human skin barrier to therapeutically relevant levels into both the epidermis and dermis and that the skin penetrating aptamer retains its biologically active conformational structure capable of binding to endogenous IL-23. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Viscoelastic properties of levan polysaccharides

    NASA Astrophysics Data System (ADS)

    Noll, Kenneth; Rende, Deniz; Ozisik, Rahmi; Toksoy-Oner, Ebru

    2014-03-01

    Levan is a naturally occurring polysaccharide that is composed of β-D-fructofuranose units with β(2-6) linkages between fructose rings. It is synthesized by the action of a secreted levansucrase (EC 2.4.1.10) that converts sucrose into the levan externally (exopolysaccharide). Levan is a homopolysaccharide that is non-toxic, water soluble,, and has anti-tumor activity and low immunological response. Therefore, levan presents great potential to be used as a novel functional biopolymer in foods, feeds, cosmetics, pharmaceutical and chemical industries. Despite these favorable properties, levan has a moderately low mechanical properties and poor film forming capability. In the current study, the agglomeration behavior of levan in water and in saline solutions was investigated at 298 and 310 K by dynamic light scattering and transmission electron microscopy (TEM). The viscoelastic properties of neat and oxidized levan films were studied via nanoindentation experiments in the quasi-static and dynamic modes The material is partially based upon work supported by NSF under Grant Nos. 1200270 and 1003574, and TUBITAK 111M232.

  11. Mycoplasma polysaccharide protects against complement

    PubMed Central

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

    2012-01-01

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

  12. Herbal polysaccharides and cough reflex.

    PubMed

    Nosalova, Gabriela; Fleskova, Dana; Jurecek, Ludovit; Sadlonova, Vladimira; Ray, Bimalendu

    2013-06-01

    In the last decades plant substances have become a leading form of treatment of many respiratory symptoms, including cough. It has been shown that compounds purified form polysaccharides from Adhatoda vasica, Withania somnifera, and Glycyrrhiza glabra have various biological activities, such as antioxidant, anti-inflammatory, immunomodulating, antispasmodic action, or antiallergic properties, and they often act as cough suppressants. This work demonstrates new natural substitutes for synthetic antitussives whose application is associated with numerous adverse effects. We investigated pharmacodynamic characteristics of arabinogalacatan samples extracted from A. vasica, W. somnifera, and G. glabra. These extracts showed the ability to reduce citric acid-induced cough in awake guinea pigs after oral administration in a dose of 50mg/kg. The strongest antitussive effect (81%) was found after application of the extract from G. glabra. There was a 67% cough suppression with A. vasica and 61% with W. somnifera, which was comparable with the antitussive activity of codeine (62%). Copyright © 2013. Published by Elsevier B.V.

  13. Kinetic simulation of hydrodynamic equivalent capsule implosions

    NASA Astrophysics Data System (ADS)

    Kwan, Thomas; Le, Ari; Schmitt, Mark; Herrmann, Hans

    2016-10-01

    We have carried out simulations of direct-drive hydrodynamic equivalent capsule implosion experiments conducted on Omega laser facility at the Laboratory of Laser Energetics of the University of Rochester. The capsules had a glass shell (SiO2) 4.87 μm with an inner diameter of 1086 μm. One was filled with deuterium (D) and tritium (T) at 6.635 and 2.475 atmospheric pressure respectively. The other capsule with D, T, and He-3 at 2.475, 2.475, and 5.55 atmospheric pressure respectively. The capsules were imploded with 60 laser beams with a square pulse length of 0.6ns of total energy of 15.6 kJ. One-dimensional radiation hydrodynamic calculations with HYDRA and kinetic particle/hybrid simulations with LSP are carried out for the post-shot analysis. HYDRA outputs at 0.6ns are linked to LSP, in which the electrons are treated as a fluid while all the ion dynamics is simulated by the standard particle-in-cell technique. Additionally, simulations with the new photon package in LSP are initiated at the beginning of the implosion to include the implosion phase of the capsule. The simulation results of density, temperature, and velocity profiles of the electrons, D, T, He-3, and SiO2species are compared with HYDRA. Detail comparisons among the kinetic simulations, rad-hydro simulations, and experimental results of neutron yield, yield ratio, fusion burn histories, and shell convergence will be presented to assess plasma kinetic effects. Work performed under the auspices of the US DOE by the Los Alamos National Laboratory under Contract No. W7405-ENG-36.

  14. Expression of type 8 capsular polysaccharide and production of toxic shock syndrome toxin 1 are associated among vaginal isolates of Staphylococcus aureus.

    PubMed Central

    Lee, J C; Liu, M J; Parsonnet, J; Arbeit, R D

    1990-01-01

    A colony immunoblot method was developed for serotyping the capsular polysaccharides expressed by Staphylococcus aureus isolates. The method was rapid and specific and was performed with either polyclonal or monoclonal antibodies specific for each of the capsule types. S. aureus isolates were obtained from patients with toxic shock syndrome (TSS) or other staphylococcal infections and from asymptomatic women with vaginal colonization. Among the vaginal isolates of S. aureus, expression of the type 8 capsule was significantly (P less than 0.001) more frequent among strains that produced TSS toxin 1 (TSST-1) than it was among TSST-1-negative strains. In contrast, the frequency of type 8 capsule expression was similar among both TSST-1-positive and -negative strains of S. aureus from patients with nonvaginal TSS. When all vaginal and nonvaginal isolates were compared, TSST-1-negative S. aureus strains were equally distributed among the type 5 and 8 and nontypeable capsule groups, whereas TSST-1-positive strains were predominantly capsule type 8. Images PMID:2279990

  15. Capsule Expression by Bovine Isolates of Staphylococcus aureus from Argentina: Genetic and Epidemiologic Analyses

    PubMed Central

    Sordelli, D. O.; Buzzola, F. R.; Gomez, M. I.; Steele-Moore, L.; Berg, D.; Gentilini, E.; Catalano, M.; Reitz, A. J.; Tollersrud, T.; Denamiel, G.; Jeric, P.; Lee, J. C.

    2000-01-01

    Staphylococcus aureus is an important cause of bovine mastitis worldwide, and effective preventive or therapeutic modalities are lacking. Although most human S. aureus isolates produce capsular polysaccharides (CPs), few reports have described the prevalence of capsules on bovine isolates. This information is important for the rational design of a vaccine for the prevention of staphylococcal mastitis. We serotyped 195 S. aureus strains isolated between 1989 and 1997 from the milk of mastitic cows in Argentina. Only 14 (7.1%) of the strains were serotype 5, and all were recovered between 1989 and 1992. Thirteen serotype 8 strains were identified, and 12 of these were isolated between 1991 and 1994. The remaining 168 isolates were nonreactive (NR) with CP serotype 5 (CP5)- or CP8-specific antibodies. Hybridization studies performed with genomic DNA from eight NR strains revealed that only three of them carried the capsule genes. Pulsed-field gel electrophoresis (PFGE) performed with 127 of the 195 S. aureus isolates revealed that most (86%) strains belonged to one of four major PFGE groups. Although 8 of 14 CP5 isolates showed a common PFGE pattern (arbitrarily defined as A1), 31 other A1 isolates from the same time period (1989 to 1992) were not CP5 positive. In contrast, only nine PFGE type B3 isolates were recovered between 1990 and 1994, and eight of these were positive for CP8 (P < 0.0003). The results of this study underscore the variability in capsule expression by S. aureus strains isolated from different geographical regions and cast doubt on the roles of CP5 and CP8 in the pathogenesis and immunoprophylaxis of bovine mastitis in Argentina. PMID:10655395

  16. Recollections of Parent Characteristics and Attachment Patterns for College Women of Intact vs. Non-Intact Families

    ERIC Educational Resources Information Center

    Kilmann, Peter R.; Carranza, Laura V.; Vendemia, Jennifer M. C.

    2006-01-01

    This study contrasted offsprings' attachment patterns and recollections of parent characteristics in two college samples: 147 females from intact biological parents and 157 females of parental divorce. Secure females from intact or non-intact families rated parents positively, while insecure females rated parents as absent, distant, and demanding.…

  17. Recollections of Parent Characteristics and Attachment Patterns for College Women of Intact vs. Non-Intact Families

    ERIC Educational Resources Information Center

    Kilmann, Peter R.; Carranza, Laura V.; Vendemia, Jennifer M. C.

    2006-01-01

    This study contrasted offsprings' attachment patterns and recollections of parent characteristics in two college samples: 147 females from intact biological parents and 157 females of parental divorce. Secure females from intact or non-intact families rated parents positively, while insecure females rated parents as absent, distant, and demanding.…

  18. N-acetylglucosamine deacetylases modulate the anchoring of the gamma-glutamyl capsule to the cell wall of Bacillus anthracis.

    PubMed

    Candela, Thomas; Balomenou, Stavroula; Aucher, Willy; Bouriotis, Vassilis; Simore, Jean-Pierre; Fouet, Agnes; Boneca, Ivo G

    2014-06-01

    Bacillus anthracis has a complex cell wall structure composed of a peptidoglycan (PG) layer to which major structures are anchored such as a neutral polysaccharide, an S-layer, and a poly-γ-D-glutamate (PDGA) capsule. Many of these structures have central roles in the biology of B. anthracis, particularly, in virulence. However, little attention has been devoted to structurally study the PG and how it is modified in the presence of these secondary cell wall components. We present here the fine structure of the PG of the encapsulated RPG1 strain harboring both pXO1 and pXO2 virulence plasmids. We show that B. anthracis has a high degree of cross-linking and its GlcNAc residues are highly modified by N-deacetylation. The PG composition is not dependent on the presence of either LPXTG proteins or the capsule. Using NMR analysis of the PG-PDGA complex, we provide evidence for the anchoring of the PDGA to the glucosamine residues. We show that anchoring of the PDGA capsule is impaired in two PG N-deacetylase mutants, Ba1961 and Ba3679. Thus, these multiple N-deactylase activities would constitute excellent drug targets in B. anthracis by simultaneously affecting its resistance to lysozyme and to phagocytosis impairing B. anthracis survival in the host.

  19. Modulation of Kingella kingae Adherence to Human Epithelial Cells by Type IV Pili, Capsule, and a Novel Trimeric Autotransporter

    PubMed Central

    Porsch, Eric A.; Kehl-Fie, Thomas E.; Geme, Joseph W. St.

    2012-01-01

    ABSTRACT Kingella kingae is an emerging bacterial pathogen that is being recognized increasingly as an important etiology of septic arthritis, osteomyelitis, and bacteremia, especially in young children. Colonization of the posterior pharynx is a key step in the pathogenesis of K. kingae disease. Previous work established that type IV pili are necessary for K. kingae adherence to the respiratory epithelium. In this study, we set out to identify additional factors that influence K. kingae interactions with human epithelial cells. We found that genetic disruption of the gene encoding a predicted trimeric autotransporter protein called Knh (Kingella NhhA homolog) resulted in reduced adherence to human epithelial cells. In addition, we established that K. kingae elaborates a surface-associated polysaccharide capsule that requires a predicted ABC-type transporter export operon called ctrABCD for surface presentation. Furthermore, we discovered that the presence of a surface capsule interferes with Knh-mediated adherence to human epithelial cells by nonpiliated organisms and that maximal adherence in the presence of a capsule requires the predicted type IV pilus retraction machinery, PilT/PilU. On the basis of the data presented here, we propose a novel adherence mechanism that allows K. kingae to adhere efficiently to human epithelial cells while remaining encapsulated and more resistant to immune clearance. PMID:23093386

  20. N-Acetylglucosamine Deacetylases Modulate the Anchoring of the Gamma-Glutamyl Capsule to the Cell Wall of Bacillus anthracis

    PubMed Central

    Candela, Thomas; Balomenou, Stavroula; Aucher, Willy; Bouriotis, Vassilis; Simore, Jean-Pierre; Fouet, Agnes

    2014-01-01

    Bacillus anthracis has a complex cell wall structure composed of a peptidoglycan (PG) layer to which major structures are anchored such as a neutral polysaccharide, an S-layer, and a poly-γ-D-glutamate (PDGA) capsule. Many of these structures have central roles in the biology of B. anthracis, particularly, in virulence. However, little attention has been devoted to structurally study the PG and how it is modified in the presence of these secondary cell wall components. We present here the fine structure of the PG of the encapsulated RPG1 strain harboring both pXO1 and pXO2 virulence plasmids. We show that B. anthracis has a high degree of cross-linking and its GlcNAc residues are highly modified by N-deacetylation. The PG composition is not dependent on the presence of either LPXTG proteins or the capsule. Using NMR analysis of the PG-PDGA complex, we provide evidence for the anchoring of the PDGA to the glucosamine residues. We show that anchoring of the PDGA capsule is impaired in two PG N-deacetylase mutants, Ba1961 and Ba3679. Thus, these multiple N-deactylase activities would constitute excellent drug targets in B. anthracis by simultaneously affecting its resistance to lysozyme and to phagocytosis impairing B. anthracis survival in the host. PMID:24833281

  1. [Improvement of Digital Capsule Endoscopy System and Image Interpolation].

    PubMed

    Zhao, Shaopeng; Yan, Guozheng; Liu, Gang; Kuang, Shuai

    2016-01-01

    Traditional capsule image collects and transmits analog image, with weak anti-interference ability, low frame rate, low resolution. This paper presents a new digital image capsule, which collects and transmits digital image, with frame rate up to 30 frames/sec and pixels resolution of 400 x 400. The image is compressed in the capsule, and is transmitted to the outside of the capsule for decompression and interpolation. A new type of interpolation algorithm is proposed, which is based on the relationship between the image planes, to obtain higher quality colour images. capsule endoscopy, digital image, SCCB protocol, image interpolation

  2. Oligodeoxynucleotide Probes for Detecting Intact Cells

    NASA Technical Reports Server (NTRS)

    Rosson, Reinhardt A.; Maurina-Brunker, Julie; Langley, Kim; Pynnonen, Christine M.

    2004-01-01

    A rapid, sensitive test using chemiluminescent oligodeoxynucleotide probes has been developed for detecting, identifying, and enumerating intact cells. The test is intended especially for use in detecting and enumerating bacteria and yeasts in potable water. As in related tests that have been developed recently for similar purposes, the oligodeoxynucleotide probes used in this test are typically targeted at either singlecopy deoxyribonucleic acid (DNA) genes (such as virulence genes) or the multiple copies (10,000 to 50,000 copies per cell) of 16S ribosomal ribonucleic acids (rRNAs). Some of those tests involve radioisotope or fluorescent labeling of the probes for reporting hybridization of probes to target nucleic acids. Others of those tests involve labeling with enzymes plus the use of chemiluminescent or chromogenic substrates to report hybridization via color or the emission of light, respectively. The present test is of the last-mentioned type. The chemiluminescence in the present test can be detected easily with relatively simple instrumentation. In developing the present test, the hybridization approach was chosen because hybridization techniques are very specific. Hybridization detects stable, inheritable genetic targets within microorganisms. These targets are not dependent on products of gene expression that can vary with growth conditions or physiological states of organisms in test samples. Therefore, unique probes can be designed to detect and identify specific genera or species of bacteria or yeast (in terms of rRNA target sequences) or can be designed to detect and identify virulence genes (genomic target sequences). Because of the inherent specificity of this system, there are few problems of cross-reactivity. Hybridization tests are rapid, but hybridization tests now available commercially lack sensitivity; typically, between 10(exp 6) and 10(exp 7) cells of the target organism are needed to ensure a reliable test. Consequently, the numbers of

  3. The IntAct molecular interaction database in 2012

    PubMed Central

    Kerrien, Samuel; Aranda, Bruno; Breuza, Lionel; Bridge, Alan; Broackes-Carter, Fiona; Chen, Carol; Duesbury, Margaret; Dumousseau, Marine; Feuermann, Marc; Hinz, Ursula; Jandrasits, Christine; Jimenez, Rafael C.; Khadake, Jyoti; Mahadevan, Usha; Masson, Patrick; Pedruzzi, Ivo; Pfeiffenberger, Eric; Porras, Pablo; Raghunath, Arathi; Roechert, Bernd; Orchard, Sandra; Hermjakob, Henning

    2012-01-01

    IntAct is an open-source, open data molecular interaction database populated by data either curated from the literature or from direct data depositions. Two levels of curation are now available within the database, with both IMEx-level annotation and less detailed MIMIx-compatible entries currently supported. As from September 2011, IntAct contains approximately 275 000 curated binary interaction evidences from over 5000 publications. The IntAct website has been improved to enhance the search process and in particular the graphical display of the results. New data download formats are also available, which will facilitate the inclusion of IntAct's data in the Semantic Web. IntAct is an active contributor to the IMEx consortium (http://www.imexconsortium.org). IntAct source code and data are freely available at http://www.ebi.ac.uk/intact. PMID:22121220

  4. Biochemical properties of polysaccharides from black pepper.

    PubMed

    Chun, Hyug; Shin, Dong Hoon; Hong, Bum Shik; Cho, Won Dai; Cho, Hong Yon; Yang, Han Chul

    2002-09-01

    The purified polysaccharides from Piper nigrum were prepared as follows: a hot water extract of pepper seeds was fractionated by ultrafiltration with a 5-kDa-membrane cartridge. A fraction with 5 kDa or bigger molecules was successively purified by open column chromatography on DEAE-Toyopearl 650C and Bio-gel P-60 with each active fraction, resulting in PN-Ib and PN-IIa, purified anti-complementary polysaccharides. None of the anti-complementary activity of any polysaccharide was changed by pronase digestion or polymyxin B treatment, but they were decreased by periodate oxidation. Analysis of component sugar and molecular mass determination of the anti-complementary polysaccharides indicated that PN-Ib with an average molecular mass of 21 kDa contained 88.5% glucose and other negligible minor monosaccharides, while PN-IIa showed a different monosaccharide composition, which contained a significant proportion of galactose, arabinose, galacturonic acid and rhamnose. The molar ratio of galactose and arabinose of PN-IIa (48 kDa) was 1.93:1. PN-1 did not react with beta-glucosyl Yariv reagent, however, PN-IIa did react, which indicated that PN-IIa might be an arabinogalactan. Based upon these results, the usefulness of purified anti-complementary polysaccharides from Piper nigrum is suggested as a supplement for immune enhancement.

  5. Structural studies of CV-70 polysaccharide.

    PubMed

    Scamparini, A; Mariuzzo, D; Fujihara, H; Jacobusi, R; Vendruscolo, C

    1997-08-01

    The goal of this paper is the characterization of the chemical structure of the water-soluble polysaccharide, CV-70, produced by bacteria Beijerinckia sp. Beijerinckia sp. is a genus of gram-negative, aerobic bacteria, usually found in sugar cane root. The CV-70 polysaccharide was produced in a fermentation medium containing 5% sucrose as the carbon source, tryptose and salts, at 25 degrees C [1]. The polysaccharide was hydrolyzed with 2 N trifluoroacetic acid at 100 degrees C for 16 h, purified, and analyzed by HPLC. Index of refraction was used for the detection of sugars. For GC-MS analysis, the CV-70 polysaccharide was derivatized through methylation and acetylation. Together with the GC-MS data, periodate oxidation studies were used to determine the possible glucosidic linkages. Carbon-13 NMR studies were carried out with hydrolyzed and silylated samples. Glucose, galactose and fucose were identified as the components in the CV-70 polysaccharide, in a 3:1:3 ratio.

  6. Preparation of green and gelatin-free nanocrystalline cellulose capsules.

    PubMed

    Zhang, Yapei; Zhao, Qing; Wang, Huashan; Jiang, Xingyu; Cha, Ruitao

    2017-05-15

    The ambiguous source and uncontrolled solubility of gelatin make it crucial to develop gelatin capsule substitutes. Nanocrystalline cellulose (NCC) of excellent mechanical performance, good biocompatibility and green origin has drawn many attentions as a new class of biomaterials. In this work, NCC capsule was prepared by dipping method with PEG and glycerol as plasticizer. The effect of PEG and glycerol on the rheological property of NCC gel and the surface morphology of NCC capsule was evaluated. The disintegration time of NCC capsule meet the criteria in United States Pharmacopoeia (USP32-701).There is no significant difference in the release of sulfuric acid between gelatin capsule and NCC capsule. NCC capsule thus has the potential as a green platform for biomedical applications in drug delivery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Experimental measurement on movement of spiral-type capsule endoscope

    PubMed Central

    Yang, Wanan; Dai, Houde; He, Yong; Qin, Fengqing

    2016-01-01

    Wireless capsule endoscope achieved great success, however, the maneuvering of wireless capsule endoscope is challenging at present. A magnetic driving instrument, including two bar magnets, a stepper motor, a motor driver, a motor controller, and a power supplier, was developed to generate rotational magnetic fields. Permanent magnet ring, magnetized as S and N poles radially and mounted spiral structure on the surface, acted as a capsule. The maximum torque passing to the capsule, rotational synchronization of capsule and motor, and the translational speed of capsule, were measured in ex vivo porcine large intestine. The experimental results illustrate that the rotational movement of the spiral-type capsule in the intestine is feasible and the cost of the magnetic driving equipment is low. As a result, the solution is promising in the future controllability. PMID:26848279

  8. Experimental measurement on movement of spiral-type capsule endoscope.

    PubMed

    Yang, Wanan; Dai, Houde; He, Yong; Qin, Fengqing

    2016-01-01

    Wireless capsule endoscope achieved great success, however, the maneuvering of wireless capsule endoscope is challenging at present. A magnetic driving instrument, including two bar magnets, a stepper motor, a motor driver, a motor controller, and a power supplier, was developed to generate rotational magnetic fields. Permanent magnet ring, magnetized as S and N poles radially and mounted spiral structure on the surface, acted as a capsule. The maximum torque passing to the capsule, rotational synchronization of capsule and motor, and the translational speed of capsule, were measured in ex vivo porcine large intestine. The experimental results illustrate that the rotational movement of the spiral-type capsule in the intestine is feasible and the cost of the magnetic driving equipment is low. As a result, the solution is promising in the future controllability.

  9. Mass Spectrometry of Intact Membrane Protein Complexes

    PubMed Central

    Laganowsky, Arthur; Reading, Eamonn; Hopper, Jonathan T.S.; Robinson, Carol V.

    2014-01-01

    Mass spectrometry of intact soluble protein complexes has emerged as a powerful technique to study the stoichiometry, structure-function and dynamics of protein assemblies. Recent developments have extended this technique to the study of membrane protein complexes where it has already revealed subunit stoichiometries and specific phospholipid interactions. Here, we describe a protocol for mass spectrometry of membrane protein complexes. The protocol begins with preparation of the membrane protein complex enabling not only the direct assessment of stoichiometry, delipidation, and quality of the target complex, but also evaluation of the purification strategy. A detailed list of compatible non-ionic detergents is included, along with a protocol for screening detergents to find an optimal one for mass spectrometry, biochemical and structural studies. This protocol also covers the preparation of lipids for protein-lipid binding studies and includes detailed settings for a Q-ToF mass spectrometer after introduction of complexes from gold-coated nanoflow capillaries. PMID:23471109

  10. Protein methylation reactions in intact pea chloroplasts

    SciTech Connect

    Niemi, K.J. )

    1989-04-01

    Post-translational protein methylation was investigated in Pisum sativum chloroplasts. Intact pea chloroplasts were incubated with ({sup 3}H-methyl)-S-adenosylmethionine under various conditions. The chloroplasts were then separated into stromal and thylakoid fractions and analyzed for radioactivity transferred to protein. Light enhanced the magnitude of labeling in both fractions. One thylakoid polypeptide with an apparent molecular mass of 43 kDa was labeled only in the light. Several other thylakoid and stromal proteins were labeled in both light and dark-labeling conditions. Both base-labile methylation, carboxy-methylesters and base-stable groups, N-methylations were found. Further characterization of the methyl-transfer reactions will be presented.

  11. Drilling to gabbro in intact ocean crust.

    PubMed

    Wilson, Douglas S; Teagle, Damon A H; Alt, Jeffrey C; Banerjee, Neil R; Umino, Susumu; Miyashita, Sumio; Acton, Gary D; Anma, Ryo; Barr, Samantha R; Belghoul, Akram; Carlut, Julie; Christie, David M; Coggon, Rosalind M; Cooper, Kari M; Cordier, Carole; Crispini, Laura; Durand, Sedelia Rodriguez; Einaudi, Florence; Galli, Laura; Gao, Yongjun; Geldmacher, Jörg; Gilbert, Lisa A; Hayman, Nicholas W; Herrero-Bervera, Emilio; Hirano, Nobuo; Holter, Sara; Ingle, Stephanie; Jiang, Shijun; Kalberkamp, Ulrich; Kerneklian, Marcie; Koepke, Jürgen; Laverne, Christine; Vasquez, Haroldo L Lledo; Maclennan, John; Morgan, Sally; Neo, Natsuki; Nichols, Holly J; Park, Sung-Hyun; Reichow, Marc K; Sakuyama, Tetsuya; Sano, Takashi; Sandwell, Rachel; Scheibner, Birgit; Smith-Duque, Chris E; Swift, Stephen A; Tartarotti, Paola; Tikku, Anahita A; Tominaga, Masako; Veloso, Eugenio A; Yamasaki, Toru; Yamazaki, Shusaku; Ziegler, Christa

    2006-05-19

    Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D.

  12. Neisseria meningitidis serogroup A capsular polysaccharide acetyltransferase, methods and compositions

    DOEpatents

    Stephens, David S [Stone Mountain, GA; Gudlavalleti, Seshu K [Kensington, MD; Tzeng, Yih-Ling [Atlanta, GA; Datta, Anup K [San Diego, CA; Carlson, Russell W [Athens, GA

    2011-02-08

    Provided are methods for recombinant production of an O-acetyltransferase and methods for acetylating capsular polysaccharides, especially those of a Serogroup A Neisseria meningitidis using the recombinant O-acetyltransferase, and immunogenic compositions comprising the acetylated capsular polysaccharide.

  13. Immobilized phosphorylase for synthesis of polysaccharides from glucose

    NASA Technical Reports Server (NTRS)

    Marshall, D. L.

    1972-01-01

    Continuous processes for enzymatic production of carbohydrates from glucose are discussed. Key reactant in process is identified as phosphorylase which catalyzes reversible formation or degradation of polysaccharide. Chemical compounds and reactions to synthesize polysaccharides are analyzed.

  14. Ice nucleation activity of polysaccharides

    NASA Astrophysics Data System (ADS)

    Bichler, Magdalena; Felgitsch, Laura; Haeusler, Thomas; Seidl-Seiboth, Verena; Grothe, Hinrich

    2015-04-01

    Heterogeneous ice nucleation is an important process in the atmosphere. It shows direct impact on our climate by triggering ice cloud formation and therefore it has much influence on the radiation balance of our planet (Lohmann et al. 2002; Mishchenko et al. 1996). The process itself is not completely understood so far and many questions remain open. Different substances have been found to exhibit ice nucleation activity (INA). Due to their vast differences in chemistry and morphology it is difficult to predict what substance will make good ice nuclei and which will not. Hence simple model substances must be found and be tested regarding INA. Our work aims at gaining to a deeper understanding of heterogeneous ice nucleation. We intend to find some reference standards with defined chemistry, which may explain the mechanisms of heterogeneous ice nucleation. A particular focus lies on biological carbohydrates in regards to their INA. Biological carbohydrates are widely distributed in all kingdoms of life. Mostly they are specific for certain organisms and have well defined purposes, e.g. structural polysaccharides like chitin (in fungi and insects) and pectin (in plants), which has also water-binding properties. Since they are widely distributed throughout our biosphere and mostly safe to use for nutrition purposes, they are well studied and easily accessible, rendering them ideal candidates as proxies. In our experiments we examined various carbohydrates, like the already mentioned chitin and pectin, as well as their chemical modifications. Lohmann U.; A Glaciation Indirect Aerosol Effect Caused by Soot Aerosols; J. Geoph. Res.; Vol. 24 No.4; pp 11-1 - 11-4; 2002 Mishchenko M.I., Rossow W.B., Macke A., Lacis A. A.; Sensitivity of Cirrus Cloud Albedo, Bidirectional Reflectance and Optical Thickness Retrieval Accuracy to Ice Particle Shape, J. Geoph. Res.; Vol. 101, No D12; pp. 16,973 - 16,985; 1996

  15. Capsular polysaccharide of Erysipelothrix rhusiopathiae, the causative agent of swine erysipelas, and its modification with phosphorylcholine.

    PubMed

    Shi, Fang; Harada, Tomoyuki; Ogawa, Yohsuke; Ono, Hiroshi; Ohnishi-Kameyama, Mayumi; Miyamoto, Toru; Eguchi, Masahiro; Shimoji, Yoshihiro

    2012-11-01

    The capsule has been implicated in the virulence of the swine pathogen Erysipelothrix rhusiopathiae, a rod-shaped, intracellular Gram-positive bacterium that has a unique phylogenetic position in the phylum Firmicutes and is a close relative of Mollicutes (mycoplasma species). In this study, we analyzed the genetic locus and composition of the capsular polysaccharide (CPS) of the Fujisawa strain of E. rhusiopathiae. Genome analysis of the Fujisawa strain revealed that the genetic locus for capsular polysaccharide synthesis (cps) is located next to an lic operon, which is involved in the incorporation and expression of phosphorylcholine (PCho). Reverse transcription-PCR analysis showed that cps and lic are transcribed as a single mRNA, indicating that the loci form an operon. Using the cell surface antigen-specific monoclonal antibody (MAb) ER21 as a probe, the capsular materials were isolated from the Fujisawa strain by hot water extraction and treatment with DNase, RNase, pronase, and N-acetylmuramidase SG, followed by anion-exchange and gel filtration chromatography. The materials were then analyzed by high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance (NMR) spectroscopy. The CPS of E. rhusiopathiae is heterogeneous and consists of the major monosaccharides galacturonic acid, galactose, mannose, glucose, arabinose, xylose, and N-acetylglucosamine and some minor monosaccharides containing ribose, rhamnose, and N-acetylgalactosamine. In addition, the capsule is modified by PCho, which comigrates with the capsular materials, as determined by Western immunoblotting, and colocalizes on the cell surface, as determined by immunogold electron microscopy. Virulence testing of PCho-defective mutants in mice demonstrated that PCho is critical for the virulence of this organism.

  16. Capsular Polysaccharide of Erysipelothrix rhusiopathiae, the Causative Agent of Swine Erysipelas, and Its Modification with Phosphorylcholine

    PubMed Central

    Shi, Fang; Harada, Tomoyuki; Ogawa, Yohsuke; Ono, Hiroshi; Ohnishi-Kameyama, Mayumi; Miyamoto, Toru; Eguchi, Masahiro

    2012-01-01

    The capsule has been implicated in the virulence of the swine pathogen Erysipelothrix rhusiopathiae, a rod-shaped, intracellular Gram-positive bacterium that has a unique phylogenetic position in the phylum Firmicutes and is a close relative of Mollicutes (mycoplasma species). In this study, we analyzed the genetic locus and composition of the capsular polysaccharide (CPS) of the Fujisawa strain of E. rhusiopathiae. Genome analysis of the Fujisawa strain revealed that the genetic locus for capsular polysaccharide synthesis (cps) is located next to an lic operon, which is involved in the incorporation and expression of phosphorylcholine (PCho). Reverse transcription-PCR analysis showed that cps and lic are transcribed as a single mRNA, indicating that the loci form an operon. Using the cell surface antigen-specific monoclonal antibody (MAb) ER21 as a probe, the capsular materials were isolated from the Fujisawa strain by hot water extraction and treatment with DNase, RNase, pronase, and N-acetylmuramidase SG, followed by anion-exchange and gel filtration chromatography. The materials were then analyzed by high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance (NMR) spectroscopy. The CPS of E. rhusiopathiae is heterogeneous and consists of the major monosaccharides galacturonic acid, galactose, mannose, glucose, arabinose, xylose, and N-acetylglucosamine and some minor monosaccharides containing ribose, rhamnose, and N-acetylgalactosamine. In addition, the capsule is modified by PCho, which comigrates with the capsular materials, as determined by Western immunoblotting, and colocalizes on the cell surface, as determined by immunogold electron microscopy. Virulence testing of PCho-defective mutants in mice demonstrated that PCho is critical for the virulence of this organism. PMID:22949554

  17. The Copper Active Site of CBM33 Polysaccharide Oxygenases

    PubMed Central

    2013-01-01

    The capacity of metal-dependent fungal and bacterial polysaccharide oxygenases, termed GH61 and CBM33, respectively, to potentiate the enzymatic degradation of cellulose opens new possibilities for the conversion of recalcitrant biomass to biofuels. GH61s have already been shown to be unique metalloenzymes containing an active site with a mononuclear copper ion coordinated by two histidines, one of which is an unusual τ-N-methylated N-terminal histidine. We now report the structural and spectroscopic characterization of the corresponding copper CBM33 enzymes. CBM33 binds copper with high affinity at a mononuclear site, significantly stabilizing the enzyme. X-band EPR spectroscopy of Cu(II)-CBM33 shows a mononuclear type 2 copper site with the copper ion in a distorted axial coordination sphere, into which azide will coordinate as evidenced by the concomitant formation of a new absorption band in the UV/vis spectrum at 390 nm. The enzyme’s three-dimensional structure contains copper, which has been photoreduced to Cu(I) by the incident X-rays, confirmed by X-ray absorption/fluorescence studies of both aqueous solution and intact crystals of Cu-CBM33. The single copper(I) ion is ligated in a T-shaped configuration by three nitrogen atoms from two histidine side chains and the amino terminus, similar to the endogenous copper coordination geometry found in fungal GH61. PMID:23540833

  18. Learning from microbial strategies for polysaccharide degradation.

    PubMed

    Hemsworth, Glyn R; Déjean, Guillaume; Davies, Gideon J; Brumer, Harry

    2016-02-01

    Complex carbohydrates are ubiquitous in all kingdoms of life. As major components of the plant cell wall they constitute both a rich renewable carbon source for biotechnological transformation into fuels, chemicals and materials, and also form an important energy source as part of a healthy human diet. In both contexts, there has been significant, sustained interest in understanding how microbes transform these substrates. Classical perspectives of microbial polysaccharide degradation are currently being augmented by recent advances in the discovery of lytic polysaccharide monooxygenases (LPMOs) and polysaccharide utilization loci (PULs). Fundamental discoveries in carbohydrate enzymology are both advancing biological understanding, as well as informing applications in industrial biomass conversion and modulation of the human gut microbiota to mediate health benefits.

  19. Influence of polysaccharides on wine protein aggregation.

    PubMed

    Jaeckels, Nadine; Meier, Miriam; Dietrich, Helmut; Will, Frank; Decker, Heinz; Fronk, Petra

    2016-06-01

    Polysaccharides are the major high-molecular weight components of wines. In contrast, proteins occur only in small amounts in wine, but contribute to haze formation. The detailed mechanism of aggregation of these proteins, especially in combination with other wine components, remains unclear. This study demonstrates the different aggregation behavior between a buffer and a model wine system by dynamic light scattering. Arabinogalactan-protein, for example, shows an increased aggregation in the model wine system, while in the buffer system a reducing effect is observed. Thus, we could show the importance to examine the behavior of wine additives under conditions close to reality, instead of simpler buffer systems. Additional experiments on melting points of wine proteins reveal that only some isoforms of thaumatin-like proteins and chitinases are involved in haze formation. We can confirm interactions between polysaccharides and proteins, but none of these polysaccharides is able to prevent haze in wine. Copyright © 2016. Published by Elsevier Ltd.

  20. Recalcitrant polysaccharide degradation by novel oxidative biocatalysts.

    PubMed

    Dimarogona, Maria; Topakas, Evangelos; Christakopoulos, Paul

    2013-10-01

    The classical hydrolytic mechanism for the degradation of plant polysaccharides by saprophytic microorganisms has been reconsidered after the recent landmark discovery of a new class of oxidases termed lytic polysaccharide monooxygenases (LPMOs). LPMOs are of increased biotechnological interest due to their implication in lignocellulosic biomass decomposition for the production of biofuels and high-value chemicals. They act on recalcitrant polysaccharides by a combination of hydrolytic and oxidative function, generating oxidized and non-oxidized chain ends. They are copper-dependent and require molecular oxygen and an external electron donor for their proper function. In this review, we present the recent findings concerning the mechanism of action of these oxidative enzymes and identify issues and questions to be addressed in the future.

  1. Antioxidant activity of medicinal plant polysaccharides.

    PubMed

    Kardosová, A; Machová, E

    2006-07-01

    Eleven polysaccharides have been isolated from the leaves of Arctium lappa var. herkules, Aloe barbadensis, Althaea officinalis var. robusta, Plantago lanceolata var. libor, aerial parts and roots of Rudbeckia fulgida var. sullivantii, stems of Mahonia aquifolium, and peach-tree (Prunus persica) gum exudates. The polysaccharides were investigated for their ability to inhibit peroxidation of soyabean lecithin liposomes by OH radicals. The highest inhibition was found with glucuronoxylans of A. officinalis var. robusta and P. lanceolata var. libor, aerial parts. Their antioxidant activity accounted for approximately 69% of the activity of the reference compound alpha-tocopherol. The activity of eight polysaccharides ranged from 20 to 45%, while the fructofuranan from P. lanceolata var. libor roots was practically inactive.

  2. Electroformation of Janus and patchy capsules

    NASA Astrophysics Data System (ADS)

    Rozynek, Zbigniew; Mikkelsen, Alexander; Dommersnes, Paul; Fossum, Jon Otto

    2014-05-01

    Janus and patchy particles have designed heterogeneous surfaces that consist of two or several patches with different materials properties. These particles are emerging as building blocks for a new class of soft matter and functional materials. Here we introduce a route for forming heterogeneous capsules by producing highly ordered jammed colloidal shells of various shapes with domains of controlled size and composition. These structures combine the functionalities offered by Janus or patchy particles, and those given by permeable shells such as colloidosomes. The simple assembly route involves the synergetic action of electro-hydrodynamic flow and electro-coalescence. We demonstrate that the method is robust and straightforwardly extendable to production of multi-patchy capsules. This forms a starting point for producing patchy colloidosomes with domains of anisotropic chemical surface properties, permeability or mixed liquid-solid phase domains, which could be exploited to produce functional emulsions, light and hollow supra-colloidosome structures, or scaffolds.

  3. Electroformation of Janus and patchy capsules

    PubMed Central

    Rozynek, Zbigniew; Mikkelsen, Alexander; Dommersnes, Paul; Fossum, Jon Otto

    2014-01-01

    Janus and patchy particles have designed heterogeneous surfaces that consist of two or several patches with different materials properties. These particles are emerging as building blocks for a new class of soft matter and functional materials. Here we introduce a route for forming heterogeneous capsules by producing highly ordered jammed colloidal shells of various shapes with domains of controlled size and composition. These structures combine the functionalities offered by Janus or patchy particles, and those given by permeable shells such as colloidosomes. The simple assembly route involves the synergetic action of electro-hydrodynamic flow and electro-coalescence. We demonstrate that the method is robust and straightforwardly extendable to production of multi-patchy capsules. This forms a starting point for producing patchy colloidosomes with domains of anisotropic chemical surface properties, permeability or mixed liquid–solid phase domains, which could be exploited to produce functional emulsions, light and hollow supra-colloidosome structures, or scaffolds. PMID:24853057

  4. Capsule- and disk-filter procedure

    USGS Publications Warehouse

    Skrobialowski, Stanley C.

    2016-01-01

    Capsule and disk filters are disposable, self-contained units composed of a pleated or woven filter medium encased in a polypropylene or other plastic housing that can be connected inline to a sample-delivery system (such as a submersible or peristaltic pump) that generates sufficient pressure (positive or negative) to force water through the filter. Filter media are available in several pore sizes, but 0.45 µm is the pore size used routinely for most studies at this time. Capsule or disk filters (table 5.2.1.A.1) are required routinely for most studies when filtering samples for trace-element analyses and are recommended when filtering samples for major-ion or other inorganic-constituent analyses.

  5. Adhesive capsulitis of the hip: a review.

    PubMed

    Looney, Colin G; Raynor, Brett; Lowe, Rebecca

    2013-12-01

    Adhesive capsulitis of the hip (ACH) is a rare clinical entity. Similar to adhesive capsulitis of the shoulder, ACH is characterized by a painful decrease in active and passive range of motion as synovial inflammation in the acute stages of the disease progresses to capsular fibrosis in the chronic stages. Once other diagnoses have been ruled out, management of ACH is tailored to reduce inflammation in the acute stages with NSAIDs, intra-articular steroid injections, and targeted physical therapy while biomechanical dysfunction in the spine, hip, sacroiliac joint, or lower limb joints is addressed. In chronic stages of the disease, intervention should focus on decreasing the progression of fibrotic changes and regaining range of motion through aggressive physical therapy. Interventions described for chronic ACH include manipulation under anesthesia; pressure dilatation; and open or arthroscopic synovectomy, lysis of adhesions, and capsular release. Surgical intervention should be considered only after failure of a minimum 3-month course of nonsurgical treatment.

  6. [Component analysis on polysaccharides in exocarp of Ginkgo biloba].

    PubMed

    Song, G; Xu, A; Chen, H; Wang, X

    1997-09-01

    This paper reports the content and component analysis on polysaccharides in exocarp of Ginkgo biloba. The results show that the content of total saccharides is 89.7%; content of polysaccharides is 84.6%; content of reductic saccharides is 5.1%; the polysaccharides are composed of glucose, fructose, galactose and rhamnose.

  7. Capsule endoscopy: Present status and future expectation

    PubMed Central

    Goenka, Mahesh K; Majumder, Shounak; Goenka, Usha

    2014-01-01

    Video capsule endoscopy (CE) since its introduction 13 years back, has revolutionized our approach to small intestinal diseases. Obscure gastrointestinal bleed (OGIB) continues to be the most important indication for CE with a high sensitivity, specificity as well as positive and negative predictive values. It is best performed during ongoing bleed or immediately thereafter. Overt OGIB has a higher diagnostic yield than occult OGIB. However, even in iron deficiency anemia, CE is emerging as important investigation after initial negative work up. In suspected Crohn’s disease (CD), CE has been shown superior to traditional imaging and endoscopic technique and should be considered after a negative ileocolonoscopy. Although CE has also been used for evaluating established CD, a high capsule retention rate precludes its use ahead of cross-sectional imaging. Celiac disease, particularly where gastro-duodenoscopy cannot be performed or is normal, can also be investigated by CE. Small bowel tumor, hereditary polyposis syndrome, and non-steroidal anti-inflammatory drugs induced intestinal damage are other indications for CE. Capsule retention is the only significant adverse outcome of CE and occurs mostly in presence of intestinal obstruction. This can be prevented by use of Patency capsule prior to CE examination. Presence of cardiac pacemaker and intracardiac devices continue to be relative contraindications for CE, though data do not suggest interference of CE with these devices. Major limitations of CE today include failure to control its movement from outside, inability of CE to acquire tissue for diagnosis, and lack of therapeutic help. With ongoing interesting and exciting developments taking place in these areas, these issues would be solved in all probability in near future. CE has the potential to become one of the most important tools in diagnostic and possibly in the therapeutic field of gastrointestinal disorder. PMID:25110430

  8. [Quality control of zhuanggu shenjin capsules].

    PubMed

    Ni, G; Chen, X; Zhang, Y; Liu, Z; Gao, Y; Quan, R; Sun, Q; Ni, H

    1996-01-01

    Studies have been made on the microscopic identification of red jinseng, dog bone, indian bread, yanhusuo and datura flower in Zhuanggu Shenjin Capsules, as well as on the identification of ginsengside and tetrahydropalmatine by TLC and the determination of icariin by dual wavelength TLC-scanning. The content of the latter compound should be no less than 0.380mg/g and the average rate of recovery 97.62% (n = 5).

  9. Rarefied Flows of Planetary Entry Capsules

    NASA Technical Reports Server (NTRS)

    Moss, James N.

    1997-01-01

    The impact of rarefaction on entry capsules and spacecraft aerothermodynamics is emphasized for various aeroassist missions. The capability of the direct simulation Monte Carlo (DSMC) method to simulate such flows is demonstrated through examples of validation studies and applications. Several space flight projects and ground-based experiments are reviewed for which rarefaction effects have significant effect on spacecraft performance or experimental measurements. This review clearly demonstrates the significant role that the DSMC method plays in characterizing such flows.

  10. Effects of food on a gastrically degraded drug: azithromycin fast-dissolving gelatin capsules and HPMC capsules.

    PubMed

    Curatolo, William; Liu, Ping; Johnson, Barbara A; Hausberger, Angela; Quan, Ernest; Vendola, Thomas; Vatsaraj, Neha; Foulds, George; Vincent, John; Chandra, Richa

    2011-07-01

    Commercial azithromycin gelatin capsules (Zithromax®) are known to be bioequivalent to commercial azithromycin tablets (Zithromax®) when dosed in the fasted state. These capsules exhibit a reduced bioavailability when dosed in the fed state, while tablets do not. This gelatin capsule negative food effect was previously proposed to be due to slow and/or delayed capsule disintegration in the fed stomach, resulting in extended exposure of the drug to gastric acid, leading to degradation to des-cladinose-azithromycin (DCA). Azithromycin gelatin capsules were formulated with "superdisintegrants" to provide fast-dissolving capsules, and HPMC capsule shells were substituted for gelatin capsule shells, in an effort to eliminate the food effect. Healthy volunteers were dosed with these dosage forms under fasted and fed conditions; pharmacokinetics were evaluated. DCA pharmacokinetics were also evaluated for the HPMC capsule subjects. In vitro disintegration of azithromycin HPMC capsules in media containing food was evaluated and compared with commercial tablets and commercial gelatin capsules. When the two fast-dissolving capsule formulations were dosed to fed subjects, the azithromycin AUC was 38.9% and 52.1% lower than after fasted-state dosing. When HPMC capsules were dosed to fed subjects, the azithromycin AUC was 65.5% lower than after fasted-state dosing. For HPMC capsules, the absolute fasting-state to fed-state decrease in azithromycin AUC (on a molar basis) was similar to the increase in DCA AUC. In vitro capsule disintegration studies revealed extended disintegration times for commercial azithromycin gelatin capsules and HPMC capsules in media containing the liquid foods milk and Ensure®. Interaction of azithromycin gelatin and HPMC capsules with food results in slowed disintegration in vitro and decreased bioavailability in vivo. Concurrent measurement of serum azithromycin and the acid-degradation product DCA demonstrates that the loss of azithromycin

  11. Physical, Rheological, Functional, and Film Properties of a Novel Emulsifier: Frost Grape Polysaccharide from Vitis riparia Michx.

    PubMed

    Hay, William T; Vaughn, Steven F; Byars, Jeffrey A; Selling, Gordon W; Holthaus, Derek M; Price, Neil P J

    2017-10-04

    A novel emulsifier, Frost grape polysaccharide (FGP), isolated from natural exudate of the species Vitis riparia Michx, was physically and rheologically characterized. The determination of the physical, structural, thermodynamic, emulsification, film, and rheological properties of FGP provide essential details for the commercial adoption of this novel plant polysaccharide. FGP is capable of producing exceptionally stable emulsions when compared with the industrially ubiquitous gum arabic (GA). The FGP isolate contained a negligible amount of nitrogen (0.03%), indicating that it does not contain an associated glycoprotein, unlike GA. Solutions of FGP have a high degree of thermostability, displaying no loss in viscosity with temperature cycling and no thermal degradation when held at 90 °C. FGP is an excellent film former, producing high tensile strength films which remain intact at temperatures up to 200 °C. This work identified a number of potential food and pharmaceutical applications where FGP is significantly superior to GA.

  12. Capsule Design for Hybrid Shock Ignition

    NASA Astrophysics Data System (ADS)

    Baumgaertel, J. A.; Dodd, E. S.; Loomis, E. N.

    2014-10-01

    Hybrid Shock-Ignition (HSI) is an alternate fusion energy concept that combines indirect drive and shock ignition schemes in order to access new regimes in National Ignition Facility (NIF) hohlraum physics. Building off of tetrahedral hohlraum experiments at the OMEGA laser facility, we have preliminary designs for spherical hohlraums that combine symmetrically arranged laser entrance holes for indirect-drive beams (to initially compress the capsule) and holes for direct-drive beams to drive a strong ignitor shock (to further compress and ignite the fuel). A LANL Eulerian hydrodynamic code is being used to find optimal laser drive, hohlraum, and capsule specifications, via criteria such as implosion symmetry, implosion time, and neutron yield. At first, drive will be modeled using a radiation source to mimic the hohlraum drive, and later, ignitor beams will be added. Initial capsule designs will be presented for experiments to develop the HSI platform on the sub-ignition scale OMEGA laser facility in FY15. Supported under the U.S. Department of Energy by the Los Alamos National Security, LLC under Contract DE-AC52-06NA25396. LA-UR-14-25071.

  13. Aerodynamics for the Mars Phoenix Entry Capsule

    NASA Technical Reports Server (NTRS)

    Edquist, Karl T.; Desai, Prasun N.; Schoenenberger, Mark

    2008-01-01

    Pre-flight aerodynamics data for the Mars Phoenix entry capsule are presented. The aerodynamic coefficients were generated as a function of total angle-of-attack and either Knudsen number, velocity, or Mach number, depending on the flight regime. The database was constructed using continuum flowfield computations and data from the Mars Exploration Rover and Viking programs. Hypersonic and supersonic static coefficients were derived from Navier-Stokes solutions on a pre-flight design trajectory. High-altitude data (free-molecular and transitional regimes) and dynamic pitch damping characteristics were taken from Mars Exploration Rover analysis and testing. Transonic static coefficients from Viking wind tunnel tests were used for capsule aerodynamics under the parachute. Static instabilities were predicted at two points along the reference trajectory and were verified by reconstructed flight data. During the hypersonic instability, the capsule was predicted to trim at angles as high as 2.5 deg with an on-axis center-of-gravity. Trim angles were predicted for off-nominal pitching moment (4.2 deg peak) and a 5 mm off-axis center-ofgravity (4.8 deg peak). Finally, hypersonic static coefficient sensitivities to atmospheric density were predicted to be within uncertainty bounds.

  14. Analysis of 2011 Defect Imaging Capsule Implosions

    NASA Astrophysics Data System (ADS)

    Bradley, Paul; Cobble, James; Hsu, Scott; Magelssen, Glenn; Murphy, Thomas; Obery, Kimberly; Schmitt, Mark; Tregillis, Ian; Krasheninnikova, Natalia; Wysocki, Frederick

    2011-10-01

    Los Alamos is engaged in a project to design high neutron fluence feature-driven mix experiments for the National Ignition Facility in 2012. These results will be relevant for determining how much imperfection capsules can have in inertial fusion energy. To prepare for NIF, we fielded shots on the Omega laser in January and July 2011 with a 40 beam polar direct drive configuration similar to what we will employ on NIF. The capsules were 15 to 17 micron CH plastic shells about 880 microns in diameter filled with 5 atm of D2 gas. We fielded capsules with different dopant layers and different depth equatorial grooves that were about 30 microns wide. We obtained radius versus time plots, radiographs, neutron yields, ion temperatures, burn widths, streak spectra, among other data. Preliminary calculations show that we match the radius versus time plots within about the data error and we have reasonable matches to the other data. We will will present these results and additional detailed comparisons of calculations to data. Work performed by Los Alamos National Laboratory under contract DE-AC52-06NA25396 for the National Nuclear Security Administration of the U.S. Department of Energy.

  15. Analysis of the Protein Kinase A-Regulated Proteome of Cryptococcus neoformans Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation

    PubMed Central

    Geddes, J. M. H.; Caza, M.; Croll, D.; Stoynov, N.; Foster, L. J.

    2016-01-01

    ABSTRACT The opportunistic fungal pathogen Cryptococcus neoformans causes life-threatening meningitis in immunocompromised individuals. The expression of virulence factors, including capsule and melanin, is in part regulated by the cyclic-AMP/protein kinase A (cAMP/PKA) signal transduction pathway. In this study, we investigated the influence of PKA on the composition of the intracellular proteome to obtain a comprehensive understanding of the regulation that underpins virulence. Through quantitative proteomics, enrichment and bioinformatic analyses, and an interactome study, we uncovered a pattern of PKA regulation for proteins associated with translation, the proteasome, metabolism, amino acid biosynthesis, and virulence-related functions. PKA regulation of the ubiquitin-proteasome pathway in C. neoformans showed a striking parallel with connections between PKA and protein degradation in chronic neurodegenerative disorders and other human diseases. Further investigation of proteasome function with the inhibitor bortezomib revealed an impact on capsule production as well as hypersusceptibility for strains with altered expression or activity of PKA. Parallel studies with tunicamycin also linked endoplasmic reticulum stress with capsule production and PKA. Taken together, the data suggest a model whereby expression of PKA regulatory and catalytic subunits and the activation of PKA influence proteostasis and the function of the endoplasmic reticulum to control the elaboration of the polysaccharide capsule. Overall, this study revealed both broad and conserved influences of the cAMP/PKA pathway on the proteome and identified proteostasis as a potential therapeutic target for the treatment of cryptococcosis. PMID:26758180

  16. The Crystal Structure of Escherichia coli Group 4 Capsule Protein GfcC Reveals a Domain Organization Resembling That of Wza

    SciTech Connect

    Sathiyamoorthy, Karthik; Mills, Erez; Franzmann, Titus M.; Rosenshine, Ilan; Saper, Mark A.

    2012-03-15

    We report the 1.9 {angstrom} resolution crystal structure of enteropathogenic Escherichia coli GfcC, a periplasmic protein encoded by the gfc operon, which is essential for assembly of group 4 polysaccharide capsule (O-antigen capsule). Presumed gene orthologs of gfcC are present in capsule-encoding regions of at least 29 genera of Gram-negative bacteria. GfcC, a member of the DUF1017 family, is comprised of tandem {beta}-grasp (ubiquitin-like) domains (D2 and D3) and a carboxyl-terminal amphipathic helix, a domain arrangement reminiscent of that of Wza that forms an exit pore for group 1 capsule export. Unlike the membrane-spanning C-terminal helix from Wza, the GfcC C-terminal helix packs against D3. Previously unobserved in a {beta}-grasp domain structure is a 48-residue helical hairpin insert in D2 that binds to D3, constraining its position and sequestering the carboxyl-terminal amphipathic helix. A centrally located and invariant Arg115 not only is essential for proper localization but also forms one of two mostly conserved pockets. Finally, we draw analogies between a GfcC protein fused to an outer membrane {beta}-barrel pore in some species and fusion proteins necessary for secreting biofilm-forming exopolysaccharides.

  17. Basic ammonothermal GaN growth in molybdenum capsules

    NASA Astrophysics Data System (ADS)

    Pimputkar, S.; Speck, J. S.; Nakamura, S.

    2016-12-01

    Single crystal, bulk gallium nitride (GaN) crystals were grown using the basic ammonothermal method in a high purity growth environment created using a non-hermetically sealed molybdenum (Mo) capsule and compared to growths performed in a similarly designed silver (Ag) capsule and capsule-free René 41 autoclave. Secondary ion mass spectrometry (SIMS) analysis revealed transition metal free (<1×1017 cm-3) GaN crystals. Anomalously low oxygen concentrations ((2-6)×1018 cm-3) were measured in a {0001} seeded crystal boule grown using a Mo capsule, despite higher source material oxygen concentrations ((1-5)×1019 cm-3) suggesting that molybdenum (or molybdenum nitrides) may act to getter oxygen under certain conditions. Total system pressure profiles from growth runs in a Mo capsule system were comparable to those without a capsule, with pressures peaking within 2 days and slowly decaying due to hydrogen diffusional losses. Measured Mo capsule GaN growth rates were comparable to un-optimized growth rates in capsule-free systems and appreciably slower than in Ag-capsule systems. Crystal quality replicated that of the GaN seed crystals for all capsule conditions, with high quality growth occurring on the (0001) Ga-face. Optical absorption and impurity concentration characterization suggests reduced concentrations of hydrogenated gallium vacancies (VGa-Hx).

  18. Characterization of novel lactoferrin loaded capsules prepared with polyelectrolyte complexes.

    PubMed

    Wu, Qing-Xi; Zhang, Qi-Lei; Lin, Dong-Qiang; Yao, Shan-Jing

    2013-10-15

    Novel capsules loaded with lactoferrin (LF) were prepared using polyelectrolyte complexes that were formed by water soluble chitosan (WSC), sodium cellulose sulfate (NaCS) and sodium polyphosphate (PPS). Normal chitosan (soluble in acidic conditions) was chosen as a control to prepare similar capsules with NaCS and PPS. (1)H NMR and FTIR spectra analysis showed that WSC was in a form of chitosan hydrochloride which can be directly dissolved and protonated in acid-free water. SEM results showed that the capsules had a typical wall-capsule structure with a regular spherical shape and an average diameter of 1.97 mm. TGA studies revealed that the thermal stability of the capsules were enhanced and the moisture content of the drug-free/loaded capsules were 6.3% and 3.2%. SDS-PAGE results showed that the primary structures of the processed LF in the capsules were unchanged. Drug loading (LE%) and encapsulation efficiency (EE%) analysis showed that the capsules had a higher LE% (45.6%) and EE% (70.7%) than that of the control. In vitro release studies showed that the capsules had a regular and sustainable release profiles in simulated colonic fluid. All of these results indicated that the capsules prepared could be used as a candidate protein drug carrier for colon. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. High-speed precision weighing of pharmaceutical capsules

    NASA Astrophysics Data System (ADS)

    Bürmen, Miran; Pernuš, Franjo; Likar, Boštjan

    2009-11-01

    In this paper, we present a cost-effective method for fast and accurate in-line weighing of hard gelatin capsules based on the optimized capacitance sensor and real-time processing of the capsule capacitance profile resulting from 5000 capacitance measurements per second. First, the effect of the shape and size of the capacitive sensor on the sensitivity and stability of the measurements was investigated in order to optimize the performance of the system. The method was tested on two types of hard gelatin capsules weighing from 50 mg to 650 mg. The results showed that the capacitance profile was exceptionally well correlated with the capsule weight with the correlation coefficient exceeding 0.999. The mean precision of the measurements was in the range from 1 mg to 3 mg, depending on the size of the capsule and was significantly lower than the 5% weight tolerances usually used by the pharmaceutical industry. Therefore, the method was found feasible for weighing pharmaceutical hard gelatin capsules as long as certain conditions are met regarding the capsule fill properties and environment stability. The proposed measurement system can be calibrated by using only two or three sets of capsules with known weight. However, for most applications it is sufficient to use only empty and nominally filled capsules for calibration. Finally, a practical application of the proposed method showed that a single system is capable of weighing around 75 000 capsules per hour, while using multiple systems could easily increase the inspection rate to meet almost any requirements.

  20. Induction of functional secretory IgA responses in breast milk, by pneumococcal capsular polysaccharides.

    PubMed

    Finn, Adam; Zhang, Qibo; Seymour, Lynn; Fasching, Claudine; Pettitt, Emily; Janoff, Edward N

    2002-11-15

    Capsule-specific secretory IgA (s-IgA) in breast milk may enhance protection against pneumococcal disease in infants. After immunization of 3 lactating mothers with 23-valent polysaccharide vaccine, specific s-IgA, but not IgG, increased by >2-fold in milk of at least 1 subject for 6 of 7 serotypes. The s-IgA was predominantly IgA1, in secretory form, and highly specific with avidity distinct from serum IgA and IgG. Milk whey from 2 immunized women supported dose- and complement-dependent killing of Streptococcus pneumoniae serotypes 19F and 14 by human neutrophils, as did purified s-IgA to serotype 19F. These data reveal that capsule-specific human s-IgA in breast milk can initiate killing of S. pneumoniae, providing proof of concept that vaccine-induced human mucosal s-IgA can support functional bactericidal activity. Determining the biologic role for s-IgA in killing and inhibiting adherence of S. pneumoniae in vivo will contribute to the development of mucosal vaccines against S. pneumoniae.

  1. Evidence for Branching in Cryptococcal Capsular Polysaccharides and Consequences on its Biological Activity

    PubMed Central

    Cordero, Radames J.B.; Frases, Susana; Guimaräes, Allan J.; Rivera, Johanna; Casadevall, Arturo

    2011-01-01

    SUMMARY The encapsulated fungus Cryptococcus neoformans is a common cause of life-threatening disease in immunocompromised individuals. Its major virulence determinant is the polysaccharide (PS) capsule. An unsolved problem in cryptococcal biology is whether the PSs composing the capsule are linear or complex branched polymers, as well as the implications of this structural composition in pathogenesis. In this study we approached the problem by combining static and dynamic light scattering, viscosity analysis, and high-resolution microscopy and correlated the findings with biological properties. Analysis of the dependence of capsular PS molecular mass and the radius of gyration provided strong evidence against a simple linear PS configuration. Shape factors calculated from light scattering measurements in solution revealed values consistent with polymer branching. Furthermore, viscosity measurements provided complementary evidence for structural branching. Electron microscopy showed PS spherical-like structures similar to other branched PS. Finally, we show that the capacity of capsular PS to interfere in complement-mediated phagocytosis, inhibit nitric oxide production by macrophage-like cells, protect against reactive oxygen species, antibody reactivity and half-life in serum were influenced by the degree of branching, providing evidence for the notion that PS branching is an important parameter in determining the biological activity of C. neoformans PS. PMID:21208301

  2. Evidence for branching in cryptococcal capsular polysaccharides and consequences on its biological activity.

    PubMed

    Cordero, Radames J B; Frases, Susana; Guimaräes, Allan J; Rivera, Johanna; Casadevall, Arturo

    2011-02-01

    The encapsulated fungus Cryptococcus neoformans is a common cause of life-threatening disease in immunocompromised individuals. Its major virulence determinant is the polysaccharide (PS) capsule. An unsolved problem in cryptococcal biology is whether the PSs composing the capsule are linear or complex branched polymers, as well as the implications of this structural composition in pathogenesis. In this study we approached the problem by combining static and dynamic light scattering, viscosity analysis, and high-resolution microscopy and correlated the findings with biological properties. Analysis of the dependence of capsular PS molecular mass and the radius of gyration provided strong evidence against a simple linear PS configuration. Shape factors calculated from light scattering measurements in solution revealed values consistent with polymer branching. Furthermore, viscosity measurements provided complementary evidence for structural branching. Electron microscopy showed PS spherical-like structures similar to other branched PS. Finally, we show that the capacity of capsular PS to interfere in complement-mediated phagocytosis, inhibit nitric oxide production by macrophage-like cells, protect against reactive oxygen species, antibody reactivity and half-life in serum were influenced by the degree of branching, providing evidence for the notion that PS branching is an important parameter in determining the biological activity of C. neoformans PS.

  3. A unique capsular polysaccharide structure from the psychrophilic marine bacterium Colwellia psychrerythraea 34H that mimics antifreeze (glyco)proteins.

    PubMed

    Carillo, Sara; Casillo, Angela; Pieretti, Giuseppina; Parrilli, Ermenegilda; Sannino, Filomena; Bayer-Giraldi, Maddalena; Cosconati, Sandro; Novellino, Ettore; Ewert, Marcela; Deming, Jody W; Lanzetta, Rosa; Marino, Gennaro; Parrilli, Michelangelo; Randazzo, Antonio; Tutino, Maria L; Corsaro, M Michela

    2015-01-14

    The low temperatures of polar regions and high-altitude environments, especially icy habitats, present challenges for many microorganisms. Their ability to live under subfreezing conditions implies the production of compounds conferring cryotolerance. Colwellia psychrerythraea 34H, a γ-proteobacterium isolated from subzero Arctic marine sediments, provides a model for the study of life in cold environments. We report here the identification and detailed molecular primary and secondary structures of capsular polysaccharide from C. psychrerythraea 34H cells. The polymer was isolated in the water layer when cells were extracted by phenol/water and characterized by one- and two-dimensional NMR spectroscopy together with chemical analysis. Molecular mechanics and dynamics calculations were also performed. The polysaccharide consists of a tetrasaccharidic repeating unit containing two amino sugars and two uronic acids bearing threonine as substituent. The structural features of this unique polysaccharide resemble those present in antifreeze proteins and glycoproteins. These results suggest a possible correlation between the capsule structure and the ability of C. psychrerythraea to colonize subfreezing marine environments.

  4. Escherichia coli Resistance to Nonbiocidal Antibiofilm Polysaccharides Is Rare and Mediated by Multiple Mutations Leading to Surface Physicochemical Modifications

    PubMed Central

    Travier, Laetitia; Rendueles, Olaya; Ferrières, Lionel; Herry, Jean-Marie

    2013-01-01

    Antivirulence strategies targeting bacterial behavior, such as adhesion and biofilm formation, are expected to exert low selective pressure and have been proposed as alternatives to biocidal antibiotic treatments to avoid the rapid occurrence of bacterial resistance. Here, we tested this hypothesis using group 2 capsule polysaccharide (G2cps), a polysaccharidic molecule previously shown to impair bacterium-surface interactions, and we investigated the nature of bacterial resistance to a nonbiocidal antibiofilm strategy. We screened an Escherichia coli mutant library for an increased ability to form biofilm in the presence of G2cps, and we identified several mutants displaying partial but not total resistance to this antibiofilm polysaccharide. Our genetic analysis showed that partial resistance to G2cps results from multiple unrelated mutations leading to modifications in surface physicochemical properties that counteract the changes in ionic charge and Lewis base properties induced by G2cps. Moreover, some of the identified mutants harboring improved biofilm formation in the presence of G2cps were also partially resistant to other antibiofilm molecules. This study therefore shows that alterations of bacterial surface properties mediate only partial resistance to G2cps. It also experimentally validates the potential value of nonbiocidal antibiofilm strategies, since full resistance to antibiofilm compounds is rare and potentially unlikely to arise in clinical settings. PMID:23733462

  5. Differential Regulation of Protein- and Polysaccharide-Specific Ig Isotype Production In Vivo in Response to Intact Streptococcus pneumoniae

    DTIC Science & Technology

    2006-01-01

    response [3]. More recently, a normal pathogen-specific IgG isotype response to Borrelia burgdorferi was observed in TLR2-/- mice, although this...was associated with a higher burden of pathogen [113]. However, MyD88-/- mice infected with B. burgdorferi demonstrated elevated B. burgdorferi

  6. Lifting the mask: identification of new small molecule inhibitors of uropathogenic Escherichia coli group 2 capsule biogenesis.

    PubMed

    Goller, Carlos C; Arshad, Mehreen; Noah, James W; Ananthan, Subramaniam; Evans, Carrie W; Nebane, N Miranda; Rasmussen, Lynn; Sosa, Melinda; Tower, Nichole A; White, E Lucile; Neuenswander, Benjamin; Porubsky, Patrick; Maki, Brooks E; Rogers, Steven A; Schoenen, Frank; Seed, Patrick C

    2014-01-01

    Uropathogenic Escherichia coli (UPEC) is the leading cause of community-acquired urinary tract infections (UTIs), with over 100 million UTIs occurring annually throughout the world. Increasing antimicrobial resistance among UPEC limits ambulatory care options, delays effective treatment, and may increase overall morbidity and mortality from complications such as urosepsis. The polysaccharide capsules of UPEC are an attractive target a therapeutic, based on their importance in defense against the host immune responses; however, the large number of antigenic types has limited their incorporation into vaccine development. The objective of this study was to identify small-molecule inhibitors of UPEC capsule biogenesis. A large-scale screening effort entailing 338,740 compounds was conducted in a cell-based, phenotypic screen for inhibition of capsule biogenesis in UPEC. The primary and concentration-response assays yielded 29 putative inhibitors of capsule biogenesis, of which 6 were selected for further studies. Secondary confirmatory assays identified two highly active agents, named DU003 and DU011, with 50% inhibitory concentrations of 1.0 µM and 0.69 µM, respectively. Confirmatory assays for capsular antigen and biochemical measurement of capsular sugars verified the inhibitory action of both compounds and demonstrated minimal toxicity and off-target effects. Serum sensitivity assays demonstrated that both compounds produced significant bacterial death upon exposure to active human serum. DU011 administration in mice provided near complete protection against a lethal systemic infection with the prototypic UPEC K1 isolate UTI89. This work has provided a conceptually new class of molecules to combat UPEC infection, and future studies will establish the molecular basis for their action along with efficacy in UTI and other UPEC infections.

  7. Lifting the Mask: Identification of New Small Molecule Inhibitors of Uropathogenic Escherichia coli Group 2 Capsule Biogenesis

    PubMed Central

    Noah, James W.; Ananthan, Subramaniam; Evans, Carrie W.; Nebane, N. Miranda; Rasmussen, Lynn; Sosa, Melinda; Tower, Nichole A.; White, E. Lucile; Neuenswander, Benjamin; Porubsky, Patrick; Maki, Brooks E.; Rogers, Steven A.; Schoenen, Frank; Seed, Patrick C.

    2014-01-01

    Uropathogenic Escherichia coli (UPEC) is the leading cause of community-acquired urinary tract infections (UTIs), with over 100 million UTIs occurring annually throughout the world. Increasing antimicrobial resistance among UPEC limits ambulatory care options, delays effective treatment, and may increase overall morbidity and mortality from complications such as urosepsis. The polysaccharide capsules of UPEC are an attractive target a therapeutic, based on their importance in defense against the host immune responses; however, the large number of antigenic types has limited their incorporation into vaccine development. The objective of this study was to identify small-molecule inhibitors of UPEC capsule biogenesis. A large-scale screening effort entailing 338,740 compounds was conducted in a cell-based, phenotypic screen for inhibition of capsule biogenesis in UPEC. The primary and concentration-response assays yielded 29 putative inhibitors of capsule biogenesis, of which 6 were selected for further studies. Secondary confirmatory assays identified two highly active agents, named DU003 and DU011, with 50% inhibitory concentrations of 1.0 µM and 0.69 µM, respectively. Confirmatory assays for capsular antigen and biochemical measurement of capsular sugars verified the inhibitory action of both compounds and demonstrated minimal toxicity and off-target effects. Serum sensitivity assays demonstrated that both compounds produced significant bacterial death upon exposure to active human serum. DU011 administration in mice provided near complete protection against a lethal systemic infection with the prototypic UPEC K1 isolate UTI89. This work has provided a conceptually new class of molecules to combat UPEC infection, and future studies will establish the molecular basis for their action along with efficacy in UTI and other UPEC infections. PMID:24983234

  8. SURGICAL INTERVENTION AND ACCOMMODATIVE RESPONSES: I. CENTRIPETAL CILIARY BODY, CAPSULE AND LENS MOVEMENT IN RHESUS MONKEYS OF VARYING AGE

    PubMed Central

    Croft, Mary Ann; Mcdonald, Jared P.; James, Rebecca J.; Heatley, Gregg A.; Lin, Ting-Li; Lütjen-Drecoll, Elke; Kaufman, Paul L.

    2009-01-01

    Purpose To determine how surgically altering the normal relationship between the lens and the ciliary body in rhesus monkeys affects centripetal ciliary body and lens movement. Methods In 18 rhesus monkey eyes (aged 6–27 years), accommodation was induced before and after surgery by electrical stimulation of the Edinger-Westphal (E–W) nucleus. Accommodative amplitude was measured by coincidence refractometry. Goniovideography was performed before and after intra- and extra-capsular lens extraction (ICLE, ECLE) and anterior regional zonulolysis. Centripetal lens/capsule movements, centripetal ciliary process (CP) movements, and circumlental space were measured by computerized image analysis of the goniovideography images. Results Centripetal accommodative CP and capsule movement increased in velocity and amplitude post-ECLE compared to pre-ECLE regardless of age (n=5). The presence of the lens substance retarded capsule movement by ~21% in the young eyes and by ~62% in the older eyes. Post-ICLE compared to pre-ICLE centripetal accommodative CP movement was dampened in all eyes in which the anterior vitreous was disturbed (n=7), but not in eyes in which the anterior vitreous was left intact (n=2). Following anterior regional zonulolysis (n=4), lens position shifted toward the lysed quadrant during accommodation. Conclusions The presence of the lens substance, capsule zonular attachments, and Wiegers ligament may play a role in centripetal CP movement. The capsule is still capable of centripetal movement in the older eye (although at a reduced capacity) and may have the ability to produce ~6 diopters of accommodation in the presence of a normal young crystalline lens or a similar surrogate. PMID:18552393

  9. NASA Hubble Sees Comet ISON Intact

    NASA Image and Video Library

    2013-10-09

    This image from NASA Hubble Space Telescope of the sunward plunging comet ISON suggests that the comet is intact despite some predictions that the fragile icy nucleus might disintegrate as the sun warms it. In this NASA Hubble Space Telescope image taken on October 9, 2013 the comet's solid nucleus is unresolved because it is so small. If the nucleus broke apart then Hubble would have likely seen evidence for multiple fragments. Moreover, the coma or head surrounding the comet's nucleus is symmetric and smooth. This would probably not be the case if clusters of smaller fragments were flying along. What's more, a polar jet of dust first seen in Hubble images taken in April is no longer visible and may have turned off. This color composite image was assembled using two filters. The comet's coma appears cyan, a greenish-blue color due to gas, while the tail is reddish due to dust streaming off the nucleus. The tail forms as dust particles are pushed away from the nucleus by the pressure of sunlight. The comet was inside Mars' orbit and 177 million miles from Earth when photographed. Comet ISON is predicted to make its closest approach to Earth on 26 December, at a distance of 39.9 million miles. http://photojournal.jpl.nasa.gov/catalog/PIA18153

  10. Ureide degradation pathways in intact soybean leaves.

    PubMed

    Vadez, V; Sinclair, T R

    2000-08-01

    Ureides dramatically accumulate in shoots of N(2)-fixing soybean (Glycine max L. Merr.) under water deficit and this accumulation is higher in cultivars that have N(2) fixation that is sensitive to water deficit. One possible explanation is that ureide accumulation is associated with a feedback inhibition of nitrogenase activity. A critical factor involved in ureide accumulation is likely to be the rate of ureide degradation in the leaves. There exists, however, a controversy concerning the pathway of allantoic acid degradation in soybean. Allantoate amidinohydrolase was reported to be the pathway of degradation in studies using the cultivar Maple Arrow and allantoate amidohydrolase was the pathway that existed in the cultivar Williams. This investigation was undertaken to resolve the existence of these two pathways. An in situ technique was developed to examine the response of ureide degradation in leaf tissue to various treatments. In addition, the response of ureide accumulation and N(2) fixation activity was measured for intact plants in response to treatments that differentially influenced the two degradation pathways. The results from these studies confirmed that Maple Arrow and Williams degraded allantoic acid by different pathways as originally reported. The existence of two degradation pathways within the soybean germplasm opens the possibility of modifying ureide degradation to minimize the influence of soil water deficits on N(2) fixation activity.

  11. [Pulmonary atresia with an intact interventricular septum].

    PubMed

    Godart, F; Fall, A L; Francart, C; Brevière, G M; Cajot, M A; Rey, C

    2005-05-01

    We report this centre's experience of the treatment and follow up of pulmonary atresia with an intact septum. 35 infants were seen during the neonatal period. Opening via catheterisation was attempted in 21 patients with initial success in 10, and 11 failures leading to urgent surgery (surgical opening, n=9) and isolated Blalock-Taussig anastomosis (n=2). Fourteen other patients underwent immediate surgery: surgical opening, n=3, and Blalock alone, n=11. Four patients died in the neonatal period: 1 after successful opening via catheterisation, 3 others after Blalock anastomosis. Five others with a Blalock anastomosis died suddenly later. By the end of follow up, 16 patients had undergone biventricular type repair, of which 7 required additional procedures. 10 others had undergone cavo-pulmonary type repair, including 4 infants in whom the initial strategy of biventricular repair had failed. The only predictive factors at birth for subsequent progression to biventricular type repair were: larger tricuspid diameter at echography (10.9 +/- 2.25 mm versus 6.34 +/- 1.74 mm, p = 0.0007) or at angiography (10.07 +/- 2.09 mm versus 8.04 +/- 2.42 mm, p = 0.039), and the right ventricular morphology (p = 0.0011) with more tripartite ventricles, and less bipartite or even unipartite ones in the biventricular group.

  12. Uranium migration through intact sandstone cores

    NASA Astrophysics Data System (ADS)

    Read, D.; Lawless, T. A.; Sims, R. J.; Butter, K. R.

    1993-06-01

    Uranium is often considered to be a mobile radioelement in the natural environment owing to its tendency to form stable complexes with a number of aqueous anions, particularly in oxidising milieu. A series of infiltration experiments were devised to investigate this migration behaviour under rigidly controlled laboratory conditions. Intact cores of Permo-Triassic Clashach Sandstone were pre-equilibrated with synthetic groundwater solutions and continuous flow-through of uranium monitored together with pH and concentrations of other ions. Prior to performing each experiment a simulation was carried out using a one-dimensional coupled chemical transport code, encompassing a thermodynamic description of the electrical double layer. These calculations together with electron microscopy indicated the potential role played by iron oxyhydroxide grain coatings in retarding the uranium plume. Thus, a second series of experiments was initiated on pre-acidified cores from which all surface exposed iron had been removed, allowing an assessment of the retention capacity of non-ferric components. Taken together, the data clearly illustrate the strong affinity of aqueous uranium species for natural surfaces even under strongly oxidising conditions. The success of the model in predicting a priori the dominant trends in uranium migration behaviour is encouraging and may aid in prioritising analytical requirements for investigations in more complex geochemical situations than those studied here.

  13. Polysaccharide-based strategies for heart tissue engineering.

    PubMed

    Silva, Amanda K A; Juenet, Maya; Meddahi-Pellé, Anne; Letourneur, Didier

    2015-02-13

    Polysaccharides are abundant biomolecules in nature presenting important roles in a wide variety of living systems processes. Considering the structural and biological functions of polysaccharides, their properties have raised interest for tissue engineering. Herein, we described the latest advances in cardiac tissue engineering mediated by polysaccharides. We reviewed the data already obtained in vitro and in vivo in this field with several types of polysaccharides. Cardiac injection, intramyocardial in situ polymerization strategies, and scaffold-based approaches involving polysaccharides for heart tissue engineering are thus discussed.

  14. Motion of an elastic capsule in a square microfluidic channel.

    PubMed

    Kuriakose, S; Dimitrakopoulos, P

    2011-07-01

    In the present study we investigate computationally the steady-state motion of an elastic capsule along the centerline of a square microfluidic channel and compare it with that in a cylindrical tube. In particular, we consider a slightly over-inflated elastic capsule made of a strain-hardening membrane with comparable shearing and area-dilatation resistance. Under the conditions studied in this paper (i.e., small, moderate, and large capsules at low and moderate flow rates), the capsule motion in a square channel is similar to and thus governed by the same scaling laws with the capsule motion in a cylindrical tube, even though in the channel the cross section in the upstream portion of large capsules is nonaxisymmetric (i.e., square-like with rounded corners). When the hydrodynamic forces on the membrane increase, the capsule develops a pointed downstream edge and a flattened rear (possibly with a negative curvature) so that the restoring tension forces are increased as also happens with droplets. Membrane tensions increase significantly with the capsule size while the area near the downstream tip is the most probable to rupture when a capsule flows in a microchannel. Because the membrane tensions increase with the interfacial deformation, a suitable Landau-Levich-Derjaguin-Bretherton analysis reveals that the lubrication film thickness h for large capsules depends on both the capillary number Ca and the capsule size a; our computations determine the latter dependence to be (in dimensionless form) h ~ a(-2) for the large capsules studied in this work. For small and moderate capsule sizes a, the capsule velocity Ux and additional pressure drop ΔP+ are governed by the same scaling laws as for high-viscosity droplets. The velocity and additional pressure drop of large thick capsules also follow the dynamics of high-viscosity droplets, and are affected by the lubrication film thickness. The motion of our large thick capsules is characterized by a Ux-U ~ h ~ a(-2

  15. Motion of an elastic capsule in a square microfluidic channel

    PubMed Central

    Kuriakose, S.; Dimitrakopoulos, P.

    2013-01-01

    In the present study we investigate computationally the steady-state motion of an elastic capsule along the centerline of a square microfluidic channel and compare it with that in a cylindrical tube. In particular, we consider a slightly over-inflated elastic capsule made of a strain-hardening membrane with comparable shearing and area-dilatation resistance. Under the conditions studied in this paper (i.e. small, moderate and large capsules at low and moderate flow rates), the capsule motion in a square channel is similar to, and thus governed by the same scaling laws with the capsule motion in a cylindrical tube, even though in the channel the cross-section in the upstream portion of large capsules is non-axisymmetric (i.e. square-like with rounded corners). When the hydrodynamic forces on the membrane increase, the capsule develops a pointed downstream edge and a flattened rear (possibly with a negative curvature) so that the restoring tension forces are increased as also happens with droplets. Membrane tensions increase significantly with the capsule size while the area near the downstream tip is the most probable to rupture when a capsule flows in a microchannel. Because the membrane tensions increase with the interfacial deformation, a suitable Landau-Levich-Derjaguin-Bretherton analysis reveals that the lubrication film thickness h for large capsules depends on both the capillary number Ca and the capsule size a; our computations determine the latter dependence to be (in dimensionless form) h ~ a−2 for the large capsules studied in this work. For small and moderate capsule sizes a, the capsule velocity Ux and additional pressure drop ΔP+ are governed by the same scaling laws as for high-viscosity droplets. The velocity and additional pressure drop of large thick capsules also follow the dynamics of high-viscosity droplets, and are affected by the lubrication film thickness. The motion of our large thick capsules is characterized by a Ux−u~h~a−2

  16. Bacillus subtilis biofilm induction by plant polysaccharides

    PubMed Central

    Beauregard, Pascale B.; Chai, Yunrong; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2013-01-01

    Bacillus subtilis is a plant-beneficial Gram-positive bacterium widely used as a biofertilizer. However, relatively little is known regarding the molecular processes underlying this bacterium's ability to colonize roots. In contrast, much is known about how this bacterium forms matrix-enclosed multicellular communities (biofilms) in vitro. Here, we show that, when B. subtilis colonizes Arabidopsis thaliana roots it forms biofilms that depend on the same matrix genes required in vitro. B. subtilis biofilm formation was triggered by certain plant polysaccharides. These polysaccharides served as a signal for biofilm formation transduced via the kinases controlling the phosphorylation state of the master regulator Spo0A. In addition, plant polysaccharides are used as a source of sugars for the synthesis of the matrix exopolysaccharide. The bacterium's response to plant polysaccharides was observed across several different strains of the species, some of which are known to have beneficial effects on plants. These observations provide evidence that biofilm genes are crucial for Arabidopsis root colonization by B. subtilis and provide insights into how matrix synthesis may be triggered by this plant. PMID:23569226

  17. Fucoidans — sulfated polysaccharides of brown algae

    NASA Astrophysics Data System (ADS)

    Usov, Anatolii I.; Bilan, M. I.

    2009-08-01

    The methods of isolation of fucoidans and determination of their chemical structures are reviewed. The fucoidans represent sulfated polysaccharides of brown algae, the composition of which varies from simple fucan sulfates to complex heteropolysaccharides. The currently known structures of such biopolymers are presented. A variety of the biological activities of fucoidans is briefly summarised.

  18. Aldehyde-containing urea-absorbing polysaccharides

    NASA Technical Reports Server (NTRS)

    Mueller, W. A.; Hsu, G. C.; Marsh, H. E., Jr. (Inventor)

    1977-01-01

    A novel aldehyde containing polymer (ACP) is prepared by reaction of a polysaccharide with periodate to introduce aldehyde groups onto the C2 - C3 carbon atoms. By introduction of ether and ester groups onto the pendant primary hydroxyl solubility characteristics are modified. The ACP is utilized to absorb nitrogen bases such as urea in vitro or in vivo.

  19. Extraction and characterization of sugar beet polysaccharides

    USDA-ARS?s Scientific Manuscript database

    Sugar Beet Pulp (SBP), contains 65 to 80% (dry weight) of potentially valuable polysaccharides. We separated SBP into three fractions. The first fraction, extracted under acid conditions, was labeled pectin, the second was comprised of two sub fractions solubilized under alkaline conditions and wa...

  20. Capsular polysaccharide of Clostridium perfringens Hobbs 10.

    PubMed

    Lee, L; Cherniak, R

    1974-02-01

    A capsular polysaccharide was isolated from a strain of Clostridium perfringens Hobbs 10 type A by cold-water extraction of whole, heavily encapsulated cells. The water-soluble polymer was isolated by alcohol precipitation and purified by treatment with chloroform-butanol, cetytrimethylammonium bromide, and column gel permeation chromatography by using Bio-Gel A-5m agarose. The formation of a single precipitin line, when the isolated polysaccharide was reacted with its homologous antisera by double diffusion in gel, was considered a criterion of immunochemical purity. The purified polymer appeared as a single peak when eluted from diethylaminoethyl-Sephadex with a linear gradient of NaCl. The polysaccharide was composed of glucose, galactose, galactosamine, and iduronic acid in a molar ratio of 4.1:5.1.7:1, respectively. These constituents accounted for 83% of the dry weight. The polysaccharide appeared to have a molecular weight of 40,000 and exhibited aggregation up to 120,000. A trace of peptide material could not be removed during purification.

  1. Capsular Polysaccharide of Clostridium perfringens Hobbs 10

    PubMed Central

    Lee, Linda; Cherniak, Robert

    1974-01-01

    A capsular polysaccharide was isolated from a strain of Clostridium perfringens Hobbs 10 type A by cold-water extraction of whole, heavily encapsulated cells. The water-soluble polymer was isolated by alcohol precipitation and purified by treatment with chloroform-butanol, cetytrimethylammonium bromide, and column gel permeation chromatography by using Bio-Gel A-5m agarose. The formation of a single precipitin line, when the isolated polysaccharide was reacted with its homologous antisera by double diffusion in gel, was considered a criterion of immunochemical purity. The purified polymer appeared as a single peak when eluted from diethylaminoethyl-Sephadex with a linear gradient of NaCl. The polysaccharide was composed of glucose, galactose, galactosamine, and iduronic acid in a molar ratio of 4.1:5.1.7:1, respectively. These constituents accounted for 83% of the dry weight. The polysaccharide appeared to have a molecular weight of 40,000 and exhibited aggregation up to 120,000. A trace of peptide material could not be removed during purification. PMID:4361293

  2. Anticorrosive Microbial Polysaccharides: Structure-Function Relationships

    USDA-ARS?s Scientific Manuscript database

    Water-soluble microbial polysaccharides are often implicated in biofilm formation and are believed to mediate cell-cell aggregation and adhesion to surfaces. Generally, biofilm formation is considered harmful or undesirable, as it leads to increased drag, plugging of pores, dimished heat transfer, ...

  3. Plant-Polysaccharide-Degrading Enzymes from Basidiomycetes

    PubMed Central

    Rytioja, Johanna; Hildén, Kristiina; Yuzon, Jennifer; Hatakka, Annele; de Vries, Ronald P.

    2014-01-01

    SUMMARY Basidiomycete fungi subsist on various types of plant material in diverse environments, from living and dead trees and forest litter to crops and grasses and to decaying plant matter in soils. Due to the variation in their natural carbon sources, basidiomycetes have highly varied plant-polysaccharide-degrading capabilities. This topic is not as well studied for basidiomycetes as for ascomycete fungi, which are the main sources of knowledge on fungal plant polysaccharide degradation. Research on plant-biomass-decaying fungi has focused on isolating enzymes for current and future applications, such as for the production of fuels, the food industry, and waste treatment. More recently, genomic studies of basidiomycete fungi have provided a profound view of the plant-biomass-degrading potential of wood-rotting, litter-decomposing, plant-pathogenic, and ectomycorrhizal (ECM) basidiomycetes. This review summarizes the current knowledge on plant polysaccharide depolymerization by basidiomycete species from diverse habitats. In addition, these data are compared to those for the most broadly studied ascomycete genus, Aspergillus, to provide insight into specific features of basidiomycetes with respect to plant polysaccharide degradation. PMID:25428937

  4. Analysis Of Wetted-Foam ICF Capsule Perormance

    NASA Astrophysics Data System (ADS)

    Peterson, R.; Olson, R.; Zylstra, A.; Haines, B.; Yi, A.; Bradley, P.; Yin, L.; Leeper, R.; Kline, J.

    2016-10-01

    The performance of wetted-foam ICF capsules is investigated with the RAGE Eulerian radiation-hydrodynamics computer code. We are developing an experimental platform on NIF that employs a wetted foam liquid DT fuel layer ICF capsules. By varying the capsule temperature, the vapor density in the capsule can be prescribed, and the hot spot convergence ratio (CR) of the capsule implosion can be controlled. This allows us to investigate the fidelity of RAGE in modeling of capsule implosions as the value of CR is varied. In the NIF experiments, CR can be varied from 12 to 25. This presentation will cover simulations with RAGE of three NIF shots performed in 2016; a DD and a DT liquid fuel shot with CR =14 and a DT shot with CR =16. It will also discuss analysis of future experiments. This work was performed under auspices of the U. S. DOE by LANL.

  5. Comprehensive and Systematic Analysis of the Immunocompatibility of Polyelectrolyte Capsules.

    PubMed

    Zyuzin, Mikhail V; Díez, Paula; Goldsmith, Meir; Carregal-Romero, Susana; Teodosio, Cristina; Rejman, Joanna; Feliu, Neus; Escudero, Alberto; Almendral, María Jesús; Linne, Uwe; Peer, Dan; Fuentes, Manuel; Parak, Wolfgang J

    2017-02-15

    The immunocompability of polyelectrolyte capsules synthesized by layer-by-layer deposition has been investigated. Capsules of different architecture and composed of either non-degradable or biodegradable polymers, with either positively or negatively charged outer surface, and with micrometer size, have been used, and the capsule uptake by different cell lines has been studied and quantified. Immunocompatibility studies were performed with peripheral blood mononuclear cells (PBMCs). Data demonstrate that incubation with capsules, at concentrations relevant for practical applications, did not result in a reduced viability of cells, as it did not show an increased apoptosis. Presence of capsules also did not result in an increased expression of TNF-α, as detected with antibody staining, as well as at mRNA level. It also did not result in increased expression of IL-6, as detected at mRNA level. These results indicate that the polyelectrolyte capsules used in this study are immunocompatible.

  6. Reorientation of a Nonspherical Capsule in Creeping Shear Flow

    NASA Astrophysics Data System (ADS)

    Omori, Toshihiro; Imai, Yohsuke; Yamaguchi, Takami; Ishikawa, Takuji

    2012-03-01

    The dynamics of a capsule and a biological cell is of great interest in chemical engineering and bioengineering. Although the dynamics of a rigid spheroid is well understood by Jeffery’s theory, that of a spheroidal capsule remains unclear. In this Letter, the motion of a spheroidal capsule or a red blood cell in creeping shear flow is investigated. The results show that the orientation of a nonspherical capsule is variant under time reversal, though that of a rigid spheroid is invariant. Surprisingly, the alignment of a nonspherical capsule over a long time duration shows a transition depending on the shear rate, which can be utilized for a particle-alignment technique. These findings form a fundamental basis of the suspension mechanics of capsules and biological cells.

  7. Role of shocks and mix caused by capsule defects

    NASA Astrophysics Data System (ADS)

    Bradley, P. A.; Cobble, J. A.; Tregillis, I. L.; Schmitt, M. J.; Obrey, K. D.; Glebov, V.; Batha, S. H.; Magelssen, G. R.; Fincke, J. R.; Hsu, S. C.; Krasheninnikova, N. S.; Murphy, T. J.; Wysocki, F. J.

    2012-09-01

    An Eulerian code with a turbulent mix model is used to model a set of plastic (CH) ablator capsules with and without equatorial grooves. The "perfect" capsule results were used to calibrate simulations of capsules with equatorial grooves of different depths that provided information on increasingly perturbed implosions. Simulations with a turbulence model were able to calculate the same yield over mix (YOM) ratio (experiment/mix simulation) of 0.2 to 0.3 for thin (8-μm thick) and thick shell (15-μm thick) capsules with no grooves and thin capsules with shallow grooves. When the capsules have deep grooves, the YOM ratio increases to greater than unity, probably because the deformed shocks focus too strongly on the symmetry axis in our two-dimensional simulations. This is supported by a comparison of simulated and experimental x-ray images.

  8. Gross anatomy of the elbow capsule: a cadaveric study.

    PubMed

    Reichel, Lee M; Morales, Omar A

    2013-01-01

    The elbow is an inherently stable joint because of its bony articulation and surrounding capsuloligamentous structures. Anatomic and biomechanical studies have focused on the medial and lateral collateral ligamentous contributions to stability. In 1918, Gray provided a qualitative description of the elbow capsule and its fibers. Our study was performed to detail the gross anatomy of the elbow capsule. We evaluated the elbow capsule of 6 paired, fresh-frozen cadaveric specimens to detail gross capsular anatomy. We identified 3 distinct bands within the anterior capsule and 3 distinct bands within the posterior capsule. Further study is needed to delineate the functional meaning of these anatomic findings. Greater understanding of elbow capsule gross anatomy may lead to improved understanding of acute and chronic elbow pathoanatomy and treatment modalities. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  9. [The release of immobilized substances from Symplex capsules].

    PubMed

    Götze, M; Torner, H; Kauffold, P; König, I; Dautzenberg, H; Loth, F

    1986-04-01

    A new procedure of microencapsulation was studied with regard to substance release and quantification of diffusion processes on the capsule membrane. The permeability behaviour on the capsule membrane was especially studied in metabolites, which are essential for immobilized biological objects (i.g. preimplantative mammal embryos). Peptide and proteohormones, cyanmethemoglobin and proteins were enclosed in simple and multiple Symplex Capsules. All substances examined are able to pass the Symplex membrane. The speed of release is influenced by the size of the capsule, the ion force, temperature, concentration of immobilized substances as well as their linear and globular structur. Compared with simple capsules the release of substances from multiple capsules was delayed. Corresponding to the results found under the experimental design described the Symplex membrane can be considered as coating for the compartmentation of cells, that allows the passage of essential substances for the immobilized objects. The method of microencapsulation used and described has various ways of application.

  10. Wireless communication link for capsule endoscope at 600 MHz.

    PubMed

    Khaleghi, A; Balasingham, I

    2015-01-01

    Simulation of a wireless communication link for a capsule endoscopy is presented for monitoring of small intestine in humans. The realized communication link includes the transmitting capsule antenna, the outside body receiving antenna and the model of the human body. The capsule antenna is designed for operating at the frequency band of 600 MHz with an impedance bandwidth of 10 MHz and omnidirectional radiation pattern. The quality of the communication link is improved by using directive antenna outside body inside matching layer for electromagnetic wave tuning to the body. The outside body antenna has circular polarization that guaranteeing the communication link for different orientations of the capsule inside intestine. It is shown that the path loss for the capsule in 60 mm from the abdomen surface varies between 37-47 dB in relation to the antenna orientation. This link can establish high data rate wireless communications for capsule endoscopy.

  11. Design of a slow-release capsule using laser drilling.

    PubMed

    Jain, N K; Naik, S U

    1984-12-01

    Conventional hard gelatin capsules were made GI-tract resistant by formalin vapor treatment. The residual formalin content was 80 micrograms/capsule 24 h after treatment, which decreased with increased storage time. An in vitro GI-tract resistance test was performed by exposing the capsules to simulated gastric fluid for 4 h and then to simulated intestinal fluid for 4 h at 37 degrees C. The resistance was further confirmed by in vivo X-ray studies in human volunteers. Minute pores were drilled on the hardened shells of the capsules with a carbon dioxide gas laser. This permitted the slow passage of the encapsulated tetracycline hydrochloride when subjected to 0.1 M HCl in in vitro dissolution studies. In vitro drug release from these capsules followed zero-order kinetics after an initial lag period of 30 min. The factors influencing the in vitro release rate of tetracycline hydrochloride from these capsules are discussed.

  12. Role of shocks and mix caused by capsule defects

    SciTech Connect

    Bradley, P. A.; Cobble, J. A.; Tregillis, I. L.; Schmitt, M. J.; Obrey, K. D.; Batha, S. H.; Magelssen, G. R.; Fincke, J. R.; Hsu, S. C.; Krasheninnikova, N. S.; Murphy, T. J.; Wysocki, F. J.; Glebov, V.

    2012-09-15

    An Eulerian code with a turbulent mix model is used to model a set of plastic (CH) ablator capsules with and without equatorial grooves. The 'perfect' capsule results were used to calibrate simulations of capsules with equatorial grooves of different depths that provided information on increasingly perturbed implosions. Simulations with a turbulence model were able to calculate the same yield over mix (YOM) ratio (experiment/mix simulation) of 0.2 to 0.3 for thin (8-{mu}m thick) and thick shell (15-{mu}m thick) capsules with no grooves and thin capsules with shallow grooves. When the capsules have deep grooves, the YOM ratio increases to greater than unity, probably because the deformed shocks focus too strongly on the symmetry axis in our two-dimensional simulations. This is supported by a comparison of simulated and experimental x-ray images.

  13. Polar tent for reduced perturbation of NIF ignition capsules

    NASA Astrophysics Data System (ADS)

    Hammel, B. A.; Pickworth, L.; Stadermann, M.; Field, J.; Robey, H.; Scott, H. A.; Smalyuk, V.

    2016-10-01

    In simulations, a tent that contacts the capsule near the poles and departs tangential to the capsule surface greatly reduces the capsule perturbation, and the resulting mass injected into the hot-spot, compared to current capsule support methods. Target fabrication appears feasible with a layered tent (43-nm polyimide + 8-nm C) for increased stiffness. We are planning quantitative measurements of the resulting shell- ρR perturbation near peak implosion velocity (PV) using enhanced self-emission backlighting, achieved by adding 1% Ar to the capsule fill in Symcaps (4He + H). Layered DT implosions are also planned for an integrated test of capsule performance. We will describe the design and simulation predictions. Prepared by LLNL under Contract DE-AC52-07NA27344.

  14. Expression of nestin, desmin and vimentin in intact and regenerating muscle spindles of rat hind limb skeletal muscles.

    PubMed

    Cízková, Dana; Soukup, Tomás; Mokrý, Jaroslav

    2009-02-01

    We describe the expression and distribution patterns of nestin, desmin and vimentin in intact and regenerating muscle spindles of the rat hind limb skeletal muscles. Regeneration was induced by intramuscular isotransplantation of extensor digitorum longus (EDL) or soleus muscles from 15-day-old rats into the EDL muscle of adult female inbred Lewis rats. The host muscles with grafts were excised after 7-, 16-, 21- and 29-day survival and immunohistochemically stained. Nestin expression in intact spindles in host muscles was restricted to Schwann cells of sensory and motor nerves. In transplanted muscles, however, nestin expression was also found in regenerating "spindle fibers", 7 and 16 days after grafting. From the 21st day onwards, the regenerated spindle fibers were devoid of nestin immunoreactivity. Desmin was detected in spindle fibers at all developmental stages in regenerating as well as in intact spindles. Vimentin was expressed in cells of the outer and inner capsules of all muscle spindles and in newly formed myoblasts and myotubes of regenerating spindles 7 days after grafting. Our results show that the expression pattern of these intermediate filaments in regenerating spindle fibers corresponds to that found in regenerating extrafusal fibers, which supports our earlier suggestion that they resemble small-diameter extrafusal fibers.

  15. Positive Youth Development, Life Satisfaction, and Problem Behaviors of Adolescents in Intact and Non-Intact Families in Hong Kong

    PubMed Central

    Shek, Daniel T. L.; Leung, Hildie

    2013-01-01

    This study investigated whether Chinese adolescents living in intact and non-intact families differed in their positive development, life satisfaction, and risk behavior. A total of 3,328 Secondary 1 students responded to measures of positive youth development (such as resilience and psychosocial competencies), life satisfaction, and risk behavior (substance abuse, delinquency, Internet addiction, consumption of pornographic materials, self-harm, and behavioral intention to engage in problem behavior). Findings revealed that adolescents growing up in intact families reported higher levels of positive developmental outcomes and life satisfaction as compared with adolescents from non-intact families. Adolescents in non-intact families also reported higher levels of risk behaviors than those growing up in intact families. PMID:24400264

  16. Structure-function relationships of immunostimulatory polysaccharides: A review.

    PubMed

    Ferreira, Sónia S; Passos, Cláudia P; Madureira, Pedro; Vilanova, Manuel; Coimbra, Manuel A

    2015-11-05

    Immunostimulatory polysaccharides are compounds capable of interacting with the immune system and enhance specific mechanisms of the host response. Glucans, mannans, pectic polysaccharides, arabinogalactans, fucoidans, galactans, hyaluronans, fructans, and xylans are polysaccharides with reported immunostimulatory activity. The structural features that have been related with such activity are the monosaccharide and glycosidic-linkage composition, conformation, molecular weight, functional groups, and branching characteristics. However, the establishment of structure-function relationships is possible only if purified and characterized polysaccharides are used and selective structural modifications performed. Aiming at contributing to the definition of the structure-function relationships necessary to design immunostimulatory polysaccharides with potential for preventive or therapeutical purposes or to be recognized as health-improving ingredients in functional foods, this review introduces basic immunological concepts required to understand the mechanisms that rule the potential claimed immunostimulatory activity of polysaccharides and critically presents a literature survey on the structural features of the polysaccharides and reported immunostimulatory activity.

  17. Polysaccharide-producing bacteria isolated from paper machine slime deposits.

    PubMed

    Rättö, M; Suihko, M-L; Siika-aho, M

    2005-03-01

    Development of novel enzymatic methods for slime deposit control in paper mills requires knowledge of polysaccharide-producing organisms and the polysaccharide structures present in deposits. In this work, 27 polysaccharide-producing bacteria were isolated from slime samples collected from different parts of a paper machine. Most of the isolates produced polysaccharides in liquid culture and nine of them were selected for production of polysaccharides for characterisation. The selected isolates belonged to seven different genera: Bacillus, Brevundimonas, Cytophaga, Enterobacter, Klebsiella, Paenibacillus and Starkeya. Using ribotyping, partial 16S rDNA sequencing, physiological tests and fatty acid analysis, four of the nine isolates: Bacillus cereus, Brevundimonas vesicularis, K. pneumoniae and P. stellifer were identified to the species level. Production of polysaccharides by the selected isolates varied between 0.07 and 1.20 g L(-1), the highest amount being produced by B. vesicularis. The polysaccharides were heteropolysaccharides with varying proportions of galactose, glucose mannose, rhamnose fucose and uronic acids.

  18. Application of residual polysaccharide-degrading enzymes in dried shiitake mushrooms as an enzyme preparation in food processing.

    PubMed

    Tatsumi, E; Konishi, Y; Tsujiyama, S

    2016-11-01

    To examine the activities of residual enzymes in dried shiitake mushrooms, which are a traditional foodstuff in Japanese cuisine, for possible applications in food processing. Polysaccharide-degrading enzymes remained intact in dried shiitake mushrooms and the activities of amylase, β-glucosidase and pectinase were high. A potato digestion was tested using dried shiitake powder. The enzymes reacted with potato tuber specimens to solubilize sugars even under a heterogeneous solid-state condition and that their reaction modes were different at 38 and 50 °C. Dried shiitake mushrooms have a potential use in food processing as an enzyme preparation.

  19. Scanning Parameter Space for NIF capsules in HYDRA

    SciTech Connect

    Fetterman, A; Herrmann, M C; Haan, S

    2004-11-10

    The authors have implemented an automated pulse shaper for NIF capsules in HYDRA. We have developed the infrastructure to do scans using the automatic pulse shaper across any n-dimensions of capsule parameter space. Using this infrastructure, we have performed several scans examining parameters for uniformly doped Beryllium capsules. To coordinate more closely with the anticipated experimental shock timing strategy, we have started to develop an automated pulse shaper which uses planar geometry and liquid DD.

  20. Multicomposite ultrathin capsules for sustained ocular delivery of ciprofloxacin hydrochloride.

    PubMed

    Bhadra, Dipankar; Gupta, Girish; Bhadra, Sulekha; Umamaheshwari, R B; Jain, Narendra

    2004-07-16

    The present work is intended to develop a sustained bioadhesive drug delivery system for delivery of Ciprofloxacin Hydrochloride in Cul-de-Sac for sustained and effective antimicrobial chemotherapy. For this, ultrathin multicomposite capsular systems were selected. Multicomposite ultrathin capsules are molecular assemblies of tailored architecture having layer-by-layer adsorption of oppositely charged macromolecules onto colloidal particles. In the present study colloidal calcium phosphate core and gluateraldehyde fixed RBCs were used as core on which alginate (-vely charged) and polyallylamine hydrochloride (+vely charged) polyelectrolyte coating was deposited alternatively upto 10th layer. The coating in each subsequent layer was determined by changes in zeta potential. Ciprofloxacin hydrochloride was loaded in the capsules by incubation with the capsules suspended in phosphate buffer saline pH 7.4. The cores of the capsules were then removed by treatment with 0.1N HCl for calcium phosphate core and by sodium hypochlorite for RBC cored capsules. The hollow ciprofloxacin HCl loaded capsules were the evaluated in-vitro for pattern of layer-by-layer drug loading, drug release, stability at various temperatures and ionic concentrations and corneal retention. The core removal process was found to have minimal effects on drug loading in capsules. The drug loading was found to be higher for RBC cored hollow capsules and hence release rate was lower as compared to calcium cored hollow capsules. Draize test for corneal irritancy proved that the capsules were not irritating. The capsules were found to deliver the ciprofloxacin in cul-de-sac of rabbit's eyes for prolonged period. Based on corneal retention studies and tear drug concentration, the capsules can be considered for suitable and safe use for sustained ocular delivery of drugs.