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Sample records for serotype 19f polysaccharide

  1. Antibiofilm activity of Actinobacillus pleuropneumoniae serotype 5 capsular polysaccharide.

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    Michael T Karwacki

    Full Text Available 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.

  2. Emerging pneumococcal carriage serotypes in a high-risk population receiving universal 7-valent pneumococcal conjugate vaccine and 23-valent polysaccharide vaccine since 2001

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    Stubbs Liz

    2009-08-01

    Full Text Available Abstract Background In Australia in June 2001, a unique pneumococcal vaccine schedule commenced for Indigenous infants; seven-valent pneumococcal conjugate vaccine (7PCV given at 2, 4, and 6 months of age and 23-valent pneumococcal polysaccharide vaccine (23PPV at 18 months of age. This study presents carriage serotypes following this schedule. Methods We conducted cross sectional surveys of pneumococcal carriage in Aboriginal children 0 to 6 years of age living in remote Aboriginal communities (RACs in 2003 and 2005. Nasal secretions were collected and processed according to published methods. Results 902 children (mean age 25 months living in 29 communities in 2003 and 818 children (mean age 35 months in 17 communities in 2005 were enrolled. 87% children in 2003 and 96% in 2005 had received two or more doses of 7PCV. From 2003 to 2005, pneumococcal carriage was reduced from 82% to 76% and reductions were apparent in all age groups; 7PCV-type carriage was reduced from 11% to 8%, and 23PPV-non-7PCV-type carriage from 31% to 25% respectively. Thus non-23PPV-type carriage increased from 57% to 67%. All these changes were statistically significant, as were changes for some specific serotypes. Shifts could not be attributed to vaccination alone. The top 10 of 40 serotypes identified were (in descending order 16F, 19A, 11A, 6C, 23B, 19F, 6A, 35B, 6B, 10A and 35B. Carriage of penicillin non-susceptible (MIC > = 0.12 μg/mL strains (15% overall was detected in serotypes (descending order 19A, 19F, 6B, 16F, 11A, 9V, 23B, and in 4 additional serotypes. Carriage of azithromycin resistant (MIC > = 2 μg/mL strains (5% overall, was detected in serotypes (descending order 23B, 17F, 9N, 6B, 6A, 11A, 23F, and in 10 additional serotypes including 6C. Conclusion Pneumococcal carriage remains high (~80% in this vaccinated population. Uptake of both pneumococcal vaccines increased, and carriage was reduced between 2003 and 2005. Predominant serotypes in combined

  3. Clonal distribution of pneumococcal serotype 19F isolates from Ghana

    DEFF Research Database (Denmark)

    Sparding, Nadja; Dayie, Nicholas Tete Kwaku Dzifa; Mills, Richael O.

    2015-01-01

    Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. Pneumococcal strains are classified according to their capsular polysaccharide and more than 90 different serotypes are currently known. In this project, three distinct groups of pneumococcal carriage isolates from Gh...... in Ghana in that many new clones were identified. This supports the importance of continued monitoring of pneumococcal carriage in Ghana and elsewhere when vaccines, e.g., PCV-13, have been introduced to monitor the possible future spread of antimicrobial resistant clones....

  4. Determination of saccharide content in pneumococcal polysaccharides and conjugate vaccines by GC-MSD.

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    Kim, John S; Laskowich, Erin R; Arumugham, Rasappa G; Kaiser, Raymond E; MacMichael, Gregory J

    2005-12-15

    A simple and sensitive gas chromatographic method was designed for quantitative analysis of Streptococcus pneumoniae capsular polysaccharides, activated polysaccharides, and polysaccharide conjugates. Pneumococcal serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F polysaccharide or conjugate were subjected to methanolysis in 3N hydrochloric acid in methanol followed by re-N-acetylation and trimethylsilylation. Derivatized samples were chromatographed and detected using gas chromatography with mass selective detector. Gas chromatographic results were compared with colorimetric values with agreement of 92 to 123% over the range of all samples tested. Monosaccharides released during methanolysis included hexoses, uronic acids, 6-deoxy-hexoses, amino sugars, and alditols. Quantitative recovery of monosaccharides was achieved for all serotypes by the use of a single methanolysis, derivatization, and chromatography procedure. Response factors generated from authentic monosaccharide standards were used for quantitation of pneumococcal polysaccharides and conjugates with confirmation of peak assignments by retention time and mass spectral analysis. This method allows saccharide quantitation in multivalent pneumococcal vaccine intermediates and final drug products with low-level detection (10 pg) and peak purity.

  5. Recurrent Invasive Pneumococcal Disease Serotype 12F in a Vaccinated Splenectomized Patient

    DEFF Research Database (Denmark)

    Blaabjerg, Anne Katrine; Schumacher, Anna Holst; Kantsø, Bjørn

    2016-01-01

    This is the first case report of recurrent invasive pneumococcal disease (IPD), specifically, due to serotype 12F. The patient described here was vaccinated with the 23-valent pneumococcal polysaccharide vaccine (PPV23) due to previous splenectomy, and an anti-pneumococcal IgG test concluded...

  6. The Pneumococcal Serotype 15C Capsule Is Partially O-Acetylated and Allows for Limited Evasion of 23-Valent Pneumococcal Polysaccharide Vaccine-Elicited Anti-Serotype 15B Antibodies.

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    Spencer, Brady L; Shenoy, Anukul T; Orihuela, Carlos J; Nahm, Moon H

    2017-08-01

    As a species, Streptococcus pneumoniae (the pneumococcus) utilizes a diverse array of capsular polysaccharides to evade the host. In contrast to large variations in sugar composition and linkage formation, O-acetylation is a subtle capsular modification that nonetheless has a large impact on capsular shielding and recognition of the capsule by vaccine-elicited antibodies. Serotype 15B, which is included in the 23-valent pneumococcal polysaccharide vaccine (PPV23), carries the putative O-acetyltransferase gene wciZ The coding sequence of wciZ contains eight consecutive TA repeats [(TA) 8 ]. Replication slippage is thought to result in the addition or loss of TA repeats, subsequently causing frameshift and truncation of WciZ to yield a nonacetylated serotype, 15C. Using sensitive serological tools, we show that serotype 15C isolates whose wciZ contains seven or nine TA repeats retain partial O-acetylation, while serotype 15C isolates whose wciZ contains six TA repeats have barely detectable O-acetylation. We confirmed by inhibition enzyme-linked immunosorbent assay that (TA) 7 serotype 15C is ∼0.1% as acetylated as serotype 15B, while serotype 15X is nonacetylated. To eliminate the impact of genetic background, we created isogenic serotype 15B, (TA) 7 serotype 15C, and 15BΔ wciZ (15X) strains and found that reduction or absence of WciZ-mediated O-acetylation did not affect capsular shielding from phagocytes, biofilm formation, adhesion to nasopharyngeal cells, desiccation tolerance, or murine colonization. Sera from PPV23-immunized persons opsonized serotype 15B significantly but only slightly better than serotypes 15C and 15X; thus, PPV23 may not result in expansion of serotype 15C. Copyright © 2017 American Society for Microbiology.

  7. Effect of Serotype on Pneumococcal Competition in a Mouse Colonization Model.

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    Trzciński, Krzysztof; Li, Yuan; Weinberger, Daniel M; Thompson, Claudette M; Cordy, Derrick; Bessolo, Andrew; Malley, Richard; Lipsitch, Marc

    2015-09-15

    Competitive interactions between Streptococcus pneumoniae strains during host colonization could influence the serotype distribution in nasopharyngeal carriage and pneumococcal disease. We evaluated the competitive fitness of strains of serotypes 6B, 14, 19A, 19F, 23F, and 35B in a mouse model of multiserotype carriage. Isogenic variants were constructed using clinical strains as the capsule gene donors. Animals were intranasally inoculated with a mixture of up to six pneumococcal strains of different serotypes, with separate experiments involving either clinical isolates or isogenic capsule-switch variants of clinical strain TIGR4. Upper-respiratory-tract samples were repeatedly collected from animals in order to monitor changes in the serotype ratios using quantitative PCR. A reproducible hierarchy of capsular types developed in the airways of mice inoculated with multiple strains. Serotype ranks in this hierarchy were similar among pneumococcal strains of different genetic backgrounds in different strains of mice and were not altered when tested under a range of host conditions. This rank correlated with the measure of the metabolic cost of capsule synthesis and in vitro measure of pneumococcal cell surface charge, both parameters considered to be predictors of serotype-specific fitness in carriage. This study demonstrates the presence of a robust competitive hierarchy of pneumococcal serotypes in vivo that is driven mainly, but not exclusively, by the capsule itself. Streptococcus pneumoniae (pneumococcus) is the leading cause of death due to respiratory bacterial infections but also a commensal frequently carried in upper airways. Available vaccines induce immune responses against polysaccharides coating pneumococcal cells, but with over 90 different capsular types (serotypes) identified, they can only target strains of the selected few serotypes most prevalent in disease. Vaccines not only protect vaccinated individuals against disease but also protect by

  8. Validation of an immunodiagnostic assay for detection of 13 Streptococcus pneumoniae serotype-specific polysaccharides in human urine.

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    Pride, Michael W; Huijts, Susanne M; Wu, Kangjian; Souza, Victor; Passador, Sherry; Tinder, Chunyan; Song, Esther; Elfassy, Arik; McNeil, Lisa; Menton, Ronald; French, Roger; Callahan, Janice; Webber, Chris; Gruber, William C; Bonten, Marc J M; Jansen, Kathrin U

    2012-08-01

    To improve the clinical diagnosis of pneumococcal infection in bacteremic and nonbacteremic community-acquired pneumonia (CAP), a Luminex technology-based multiplex urinary antigen detection (UAD) diagnostic assay was developed and validated. The UAD assay can simultaneously detect 13 different serotypes of Streptococcus pneumoniae by capturing serotype-specific S. pneumoniae polysaccharides (PnPSs) secreted in human urine. Assay specificity is achieved by capturing the polysaccharides with serotype-specific monoclonal antibodies (MAbs) on spectrally unique microspheres. Positivity for each serotype was based on positivity cutoff values calculated from a standard curve run on each assay plate together with positive- and negative-control urine samples. The assay is highly specific, since significant signals are detected only when each PnPS was paired with its homologous MAb-coated microspheres. Validation experiments demonstrated excellent accuracy and precision. The UAD assay and corresponding positivity cutoff values were clinically validated by assessing 776 urine specimens obtained from patients with X-ray-confirmed CAP. The UAD assay demonstrated 97% sensitivity and 100% specificity using samples obtained from patients with bacteremic, blood culture-positive CAP. Importantly, the UAD assay identified Streptococcus pneumoniae (13 serotypes) in a proportion of individuals with nonbacteremic CAP, a patient population for which the pneumococcal etiology of CAP was previously difficult to assess. Therefore, the UAD assay provides a specific, noninvasive, sensitive, and reproducible tool to support vaccine efficacy as well as epidemiological evaluation of pneumococcal disease, including CAP, in adults.

  9. The Pneumococcal Serotype 15C Capsule Is Partially O-Acetylated and Allows for Limited Evasion of 23-Valent Pneumococcal Polysaccharide Vaccine-Elicited Anti-Serotype 15B Antibodies

    OpenAIRE

    Spencer, Brady L.; Shenoy, Anukul T.; Orihuela, Carlos J.; Nahm, Moon H.

    2017-01-01

    As a species, Streptococcus pneumoniae (the pneumococcus) utilizes a diverse array of capsular polysaccharides to evade the host. In contrast to large variations in sugar composition and linkage formation, O-acetylation is a subtle capsular modification that nonetheless has a large impact on capsular shielding and recognition of the capsule by vaccine-elicited antibodies. Serotype 15B, which is included in the 23-valent pneumococcal polysaccharide vaccine (PPV23), carries the putative O-acety...

  10. Antibodies to Staphylococcus aureus Serotype 8 Capsular Polysaccharide React with and Protect against Serotype 5 and 8 Isolates

    OpenAIRE

    Park, Saeyoung; Gerber, Sabina; Lee, Jean C.

    2014-01-01

    Most Staphylococcus aureus isolates produce either a serotype 5 (CP5) or 8 (CP8) capsular polysaccharide, and the CP antigens are targets for vaccine development. Since CP5 and CP8 have similar trisaccharide repeating units, it is important to identify an epitope shared by both CP5 and CP8. To characterize cross-reactivity between CP5 and CP8, the immunogenicity of CP5 and CP8 conjugate vaccines in mice and rabbits was evaluated by serological assays. Immune sera were also tested for function...

  11. PCR deduction of invasive and colonizing pneumococcal serotypes from Venezuela: a critical appraisal.

    Science.gov (United States)

    Bello Gonzalez, Teresita; Rivera-Olivero, Ismar Alejandra; Sisco, María Carolina; Spadola, Enza; Hermans, Peter W; de Waard, Jacobus H

    2014-04-15

    Serotype surveillance of Streptococcus pneumoniae is indispensable for evaluating the potential impact of pneumococcal conjugate vaccines. Serotyping by the standard Quellung reaction is technically demanding, time consuming, and expensive. A simple and economical strategy is multiplex PCR-based serotyping. We evaluated the cost effectiveness of a modified serial multiplex PCR (mPCR), resolving 24 serotypes in four PCR reactions and optimally targeting the most prevalent invasive and colonizing pneumococcal serotypes found in Venezuela. A total of 223 pneumococcal isolates, 140 invasive and 83 carriage isolates, previously serotyped by the Quellung reaction and representing the 18 most common serotypes/groups identified in Venezuela, were serotyped with the adapted mPCR. The mPCR serotyped 76% of all the strains in the first two PCR reactions and 91% after four reactions, correctly identifying 17 serotypes/groups. An isolate could be serotyped with mPCR in less than 2 minutes versus 15 minutes for the Quellung reaction, considerably lowering labor costs. A restrictive weakness of mPCR was found for the detection of 19F strains. Most Venezuelan 19F strains were not typeable using the mPCR, and two 19F cps serotype variants were identified. The mPCR assay is an accurate, rapid, and economical method for the identification of the vast majority of the serotypes from Venezuela and can be used in place of the standard Quellung reaction. An exception is the identification of serotype 19F. In this setting, most 19F strains were not detectable with mPCR, demonstrating a need of serology-based quality control for PCR-based serotyping.

  12. Immune response to pneumococcal polysaccharides 4 and 14 in elderly and young adults. I Antibody concentrations, avidity and functional activity

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    Carlone George M

    2005-06-01

    Full Text Available Abstract Streptococcus pneumoniae is a serious worldwide pathogen and the focus of numerous vaccine development projects. Currently the most widely accepted surrogate marker for evaluating the efficacy of a given vaccine is to utilize ELISA. Measurement of antibody concentration by ELISA without reduction in cross-reactive antibodies causes an overestimation of antibody concentration and therefore protection, this is most notable in the aged, an at risk group for this infection. We compared the immune response to the pneumococcal polysaccharides (PPS 4 and 14 of 20 young to 20 elderly adults. Pre-and post-vaccination IgG antibody concentrations and antibody avidity against PPS4 and PPS14 were measured using two different enzyme-linked immunosorbant assay (ELISA absorption protocols. All sera were pre-absorbed with either cell-wall polysaccharide (CPS, or CPS and serotype 22F polysaccharide. Pre- and post-vaccination IgG antibody concentrations for serotype 4, but not 14, were significantly lowered with the additional absorption with serotype 22F polysaccharide in both age groups. Young and elderly demonstrated a significant increase from pre- to post-immunization antibody concentration, using either absorption method; and opsonophagocytic antibody titers in response to both PPS4 and PPS14. The correlation coefficients between ELISA and opsonophagocytic assays were improved by additional absorption with serotype 22F in response to serotype 4, but not serotype 14 in all age groups. Opsonophagocytic antibody titers in a sub-group of elderly (>77 years of age were significantly lower than the opsonophagocytic antibody concentrations in young adults. These results suggest the importance of eliminating cross-reactive antibodies from ELISA measurements by absorption of serum and an age-related impairment in the antibody response to pneumococcal polysaccharides.

  13. Quantitative determination of pneumococcal capsular polysaccharide serotype 14 using a modification of phenol-sulfuric acid method.

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    Cuesta, Gabriela; Suarez, Norma; Bessio, Maria I; Ferreira, Fernando; Massaldi, Hugo

    2003-01-01

    The capsular polysaccharide of Streptococcus pneumoniae, serotype 14, is part of every pneumococcal vaccine presently in the market or under development. A strategy for the quantitative determination of this polysaccharide by the phenol-sulfuric acid method is described. The modality of acid addition is shown to be the critical step for obtaining reproducible test results between different technicians. Raising the incubation temperature above 80 degrees C increased the consistency of the method by more than 60% regardless of the acid addition modality, but at the expense of some loss of sensitivity. Incubation at 110 degrees C was found necessary to obtain reproducible results within 3% for this technique, which was used to follow the enrichment of the polysaccharide during the last steps of purification. A model mixture of the component polysaccharide sugars provided an adequate and economic standard to construct the calibration curve for this assay, with absorbance reading either in the reaction tubes or in a microplate. A similar procedure may be applied to the determination of other bacterial polysaccharides as well.

  14. Serotype-specific immunoglobulin G antibody responses to pneumococcal polysaccharide vaccine in children with sickle cell anemia : Effects of continued penicillin prophylaxis

    NARCIS (Netherlands)

    Bjornson, AB; Falletta, JM; Verter, JI; Buchanan, GR; Miller, ST; Pegelow, CH; Iyer, RV; Johnstone, HS; DeBaun, MR; Wethers, DL; Woods, GM; Holbrook, CT; Becton, DL; Kinney, TR; Reaman, GH; Kalinyak, K; Grossman, NJ; Vichinsky, E; Reid, CD

    1996-01-01

    Objectives: (1) To determine serotype-specific IgG antibody responses to reimmunization with pneumococcal polysaccharide vaccine at age 5 years ski children with sickle cell anemia and (2) to determine whether continued penicillin prophylaxis had any adverse effects on these responses. Study design:

  15. MOLECULAR TYPING OF STREPTOCOCCUS PNEUMONIAE BY THE MULTIPLEX POLYMERASE CHAIN REACTION ASSAY IN ACCORDANCE TO THE PREVALENCE OF SEROTYPES IN THE RUSSIAN FEDERATION

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    N. M. Alyab'eva

    2013-01-01

    Full Text Available Aim: to compare two methods of S. pneumoniae molecular typing: classic serological method and the multiplex polymerase chain reaction (M-PCR assay modified in accordance to the date on the serotypes circulating in Russian Federation. Patients and methods: 420 pneumococcal isolates mainly from non-sterile loci were analyzed. After microbiological identification pneumococci were serologically typed with the means of specific antiserum produced by Staten Serum Institute (Denmark in latex agglutination test and/or capsular swelling method. At the same time we performed series of the M-PCR, which consisted of 7 consecutive reactions at the most. Results: serotype was identified by the means of serological method in all 420 strains of S. pneumoniae; in total we determined 24 different serotypes. By the means of the M-PCR we succeeded in identification of 95% (399/420 examined strains, and 90% of them were typed during the first 3 reactions. All isolates failed to be typed by M-PCR (n =21 have serotypes not included into the composition of the M-PCR. The results of serological and molecular typing were identical in 99,2% (396/399 of the isolates; 3 strains showed contradictory results: serotype 19A was found on serological assay and serotype 19F — on PCR assay. Conclusions: the introduced modification of M-PCR allows correct identification of pneumococcal serotype more than in 90% of strains circulating in the Russian Federation, including all serotypes of pneumococcal polysaccharide conjugate vaccine.

  16. Redistribution of Streptococcus pneumoniae Serotypes After Nationwide 13-valent Pneumococcal Conjugate Vaccine Program in Children in Northern Taiwan.

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    Cho, Ying-Chun; Chiu, Nan-Chang; Lu, Chun-Yi; Huang, Daniel Tsung-Ning; Huang, Fu-Yuan; Chang, Luan-Yin; Huang, Li-Min; Chi, Hsin

    2017-12-01

    After the introduction of 13-valent pneumococcal conjugate vaccine (PCV13) against Streptococcus pneumoniae, public health officials in Taiwan monitored a decline in circulating vaccine serotypes and the emergence of nonvaccine serotypes in children with invasive pneumococcal disease. A gradually expanded PCV13 national immunization program was launched in 2013 in Taiwan. Here, we evaluate the changes in the distribution of pneumococcal serotypes and antimicrobial nonsusceptibility in children during the evolution of vaccination policy. S. pneumoniae isolates from children with pneumococcal disease were collected and serotyped from 2010 to 2015 in northern Taiwan. PCVs were administered at the recipients' expense between 2010 and 2012, and then PCV13 was partially reimbursed by the government beginning in 2013. The distribution and diversity of serotypes were analyzed along with their antimicrobial susceptibilities. Among a total of 498 isolates, the proportion of invasive pneumococcal disease isolates declined (47.1%-10.6%) during the study period, and serotype diversity increased after 2011. Between 2010 and 2012, the dominant serotypes were 19A, 19F, 3, 6B and 14, and serotype 19A rose from 44.1% to 57.5%. Serotypes 19A, 15A, 19F and 15B were more prevalent from 2013 to 2015, and serotype 19A decreased from 42.1% to 4.5%. Serotypes 19F and 15A became the most commonly detected serotypes in 2015. Overall, PCV13 additional serotypes were reduced by 80% (P program is effective against pneumococcal disease in Taiwanese children, mainly by reducing PCV13 additional serotypes.

  17. Structural determination of Streptococcus pneumoniae repeat units in serotype 41A and 41F capsular polysaccharides to probe gene functions in the corresponding capsular biosynthetic loci

    DEFF Research Database (Denmark)

    Petersen, Bent O.; Skovsted, Ian C.; Paulsen, Berit Smestad

    2014-01-01

    (1) by anambitionto help close the remaining gaps in S. pneumoniaecapsular polysaccharide structures, and (2)by the attempt to derive functional annotationsof carbohydrate active enzymes in the biosynthesis of bacterial polysaccharides from the determined structures. Anactivitypresent in 41F...

  18. Total synthesis of a Streptococcus pneumoniae serotype 12F CPS repeating unit hexasaccharide

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    Peter H. Seeberger

    2017-01-01

    Full Text Available The Gram-positive bacterium Streptococcus pneumoniae causes severe disease globally. Vaccines that prevent S. pneumoniae infections induce antibodies against epitopes within the bacterial capsular polysaccharide (CPS. A better immunological understanding of the epitopes that protect from bacterial infection requires defined oligosaccharides obtained by total synthesis. The key to the synthesis of the S. pneumoniae serotype 12F CPS hexasaccharide repeating unit that is not contained in currently used glycoconjugate vaccines is the assembly of the trisaccharide β-D-GalpNAc-(1→4-[α-D-Glcp-(1→3]-β-D-ManpNAcA, in which the branching points are equipped with orthogonal protecting groups. A linear approach relying on the sequential assembly of monosaccharide building blocks proved superior to a convergent [3 + 3] strategy that was not successful due to steric constraints. The synthetic hexasaccharide is the starting point for further immunological investigations.

  19. Replication, neurotropism, and pathogenicity of avian paramyxovirus serotypes 1-9 in chickens and ducks.

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    Shin-Hee Kim

    Full Text Available Avian paramyxovirus (APMV serotypes 1-9 have been isolated from many different avian species. APMV-1 (Newcastle disease virus is the only well-characterized serotype, because of the high morbidity, mortality, and economic loss caused by highly virulent strains. Very little is known about the pathogenesis, replication, virulence, and tropism of the other APMV serotypes. Here, this was evaluated for prototypes strains of APMV serotypes 2-9 in cell culture and in chickens and ducks. In cell culture, only APMV-1, -3 and -5 induced syncytium formation. In chicken DF1 cells, APMV-3 replicated with an efficiency approaching that of APMV-1, while APMV-2 and -5 replicated to lower, intermediate titers and the others were much lower. Mean death time (MDT assay in chicken eggs and intracerebral pathogenicity index (ICPI test in 1-day-old SPF chicks demonstrated that APMV types 2-9 were avirulent. Evaluation of replication in primary neuronal cells in vitro as well as in the brains of 1-day-old chicks showed that, among types 2-9, only APMV-3 was neurotropic, although this virus was not neurovirulent. Following intranasal infection of 1-day-old and 2-week-old chickens, replication of APMV types 2-9 was mostly restricted to the respiratory tract, although APMV-3 was neuroinvasive and neurotropic (but not neurovirulent and also was found in the spleen. Experimental intranasal infection of 3-week-old mallard ducks with the APMVs did not produce any clinical signs (even for APMV-1 and exhibited restricted viral replication of the APMVs (including APMV-1 to the upper respiratory tract regardless of their isolation source, indicating avirulence of APMV types 1-9 in mallard ducks. The link between the presence of a furin cleavage site in the F protein, syncytium formation, systemic spread, and virulence that has been well-established with APMV-1 pathotypes was not evident with the other APMV serotypes.

  20. Epidemiology and population structure of serotypes 1, 5 and 7f carried by children in Portugal from 1996-2010 before introduction of the 10-valent and 13-valent pneumococcal conjugate vaccines.

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    Sónia T Almeida

    Full Text Available Among the over 90 serotypes of Streptococcus pneumoniae described, serotypes 1, 5, and 7F account for a significant proportion of invasive disease worldwide and are now covered by the most recent 10- and 13-valent pneumococcal conjugate vaccines (PCVs. The epidemiology of these serotypes in carriage remains poorly studied because they are rarely detected. We aimed to gain insights into the epidemiology and population structure of serotypes 1, 5 and 7F carried by children in Portugal before PCV10 and PCV13 became widely used. Isolates obtained in cross-sectional studies carried out over a 15-year period (1996-2010 were retrospectively pooled and characterized. Of 5,123 pneumococci obtained, 70 were associated with serotypes 1 (n = 21, 5 (n = 7, and 7F (n = 42. The highest prevalence detected was 3.3% for serotype 1 in 2006, 1% for serotype 5 in 2009, and 3.3% for serotype 7F in 2006; Serotype 1 was associated with PMEN international clones Sweden(1-28(ST306 and Sweden(1-40(ST304; serotype 5 was associated with Colombia(5-19(ST289; and serotype 7F was associated with Netherlands(7F-39(ST191. All these isolates were fully susceptible. Most carriers of serotypes 1 (86%, 5 (86%, and 7F (91% were older than two years but a significant association with older age was only observed for serotype 7F (p = 0.006. Evidence for cross-transmission was obtained. In conclusion, we were able to detect and characterize the rarely carried serotypes 1, 5, and 7F among healthy children in Portugal. These data will constitute an important baseline for upcoming surveillance studies aimed to establish the impact of novel PCVs targeting these serotypes in carriage.

  1. An Increase in Streptococcus pneumoniae Serotype 12F

    Centers for Disease Control (CDC) Podcasts

    2018-02-08

    Dr. Cynthia Whitney, a CDC medical doctor and Epidemiologist, discusses serotype 12F pneumoniae.  Created: 2/8/2018 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/8/2018.

  2. The diversity of Klebsiella pneumoniae surface polysaccharides.

    Science.gov (United States)

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

    2016-08-01

    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.

  3. Genetic analysis of the capsular biosynthetic locus from all 90 pneumococcal serotypes.

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    Stephen D Bentley

    2006-03-01

    Full Text Available Several major invasive bacterial pathogens are encapsulated. Expression of a polysaccharide capsule is essential for survival in the blood, and thus for virulence, but also is a target for host antibodies and the basis for effective vaccines. Encapsulated species typically exhibit antigenic variation and express one of a number of immunochemically distinct capsular polysaccharides that define serotypes. We provide the sequences of the capsular biosynthetic genes of all 90 serotypes of Streptococcus pneumoniae and relate these to the known polysaccharide structures and patterns of immunological reactivity of typing sera, thereby providing the most complete understanding of the genetics and origins of bacterial polysaccharide diversity, laying the foundations for molecular serotyping. This is the first time, to our knowledge, that a complete repertoire of capsular biosynthetic genes has been available, enabling a holistic analysis of a bacterial polysaccharide biosynthesis system. Remarkably, the total size of alternative coding DNA at this one locus exceeds 1.8 Mbp, almost equivalent to the entire S. pneumoniae chromosomal complement.

  4. Validation of the World Health Organization Enzyme-Linked Immunosorbent Assay for the Quantitation of Immunoglobulin G Serotype-Specific Anti-Pneumococcal Antibodies in Human Serum.

    Science.gov (United States)

    Lee, Hyunju; Lim, Soo Young; Kim, Kyung Hyo

    2017-10-01

    The World Health Organization (WHO) enzyme-linked immunosorbent assay (ELISA) guideline is currently accepted as the gold standard for the evaluation of immunoglobulin G (IgG) antibodies specific to pneumococcal capsular polysaccharide. We conducted validation of the WHO ELISA for 7 pneumococcal serotypes (4, 6B, 9V, 14, 18C, 19F, and 23F) by evaluating its specificity, precision (reproducibility and intermediate precision), accuracy, spiking recovery test, lower limit of quantification (LLOQ), and stability at the Ewha Center for Vaccine Evaluation and Study, Seoul, Korea. We found that the specificity, reproducibility, and intermediate precision were within acceptance ranges (reproducibility, coefficient of variability [CV] ≤ 15%; intermediate precision, CV ≤ 20%) for all serotypes. Comparisons between the provisional assignments of calibration sera and the results from this laboratory showed a high correlation > 94% for all 7 serotypes, supporting the accuracy of the ELISA. The spiking recovery test also fell within an acceptable range. The quantification limit, calculated using the LLOQ, for each of the serotypes was 0.05-0.093 μg/mL. The freeze-thaw stability and the short-term temperature stability were also within an acceptable range. In conclusion, we showed good performance using the standardized WHO ELISA for the evaluation of serotype-specific anti-pneumococcal IgG antibodies; the WHO ELISA can evaluate the immune response against pneumococcal vaccines with consistency and accuracy. © 2017 The Korean Academy of Medical Sciences.

  5. Phylogenetic analysis of emergent Streptococcus pneumoniae serotype 22F causing invasive pneumococcal disease using whole genome sequencing.

    Directory of Open Access Journals (Sweden)

    Walter H B Demczuk

    Full Text Available Since implementation of the 13-valent polyvalent conjugate vaccine (PCV13 in Canada during 2010, the proportion of PCV13 serotypes causing invasive pneumococcal disease (IPD has declined from 55% (n = 1492 in 2010 to 31% (n = 764 in 2014. A concurrent increase of non-PCV13 serotypes has occurred and 22F has become the most prevalent serotype in Canada increasing from 7% (n = 183 to 11% (n = 283. Core single nucleotide variant phylogenetic analysis was performed on 137 Streptococcus pneumoniae serotype 22F isolates collected across Canada from 2005-2015. Six phylogenetic lineages (n = 117 were identified among a serotype 22F/ST433 clonal complex (CC, including a recently expanding erythromycin-resistant clone. Erythromycin-resistance was observed in 25 isolates possessing ermB, mef or a 23S rRNA A2061G point mutation; 2 penicillin-resistant isolates had recombinant pbp1a, pbp2a and/or pbp2x; 3 tetracycline-resistant isolates contained tetM; and 1 isolate was multidrug-resistant. Virulence factor analysis indicated a high level of homogeneity among the 22F/ST433 clonal complex strains. A group of 6 phylogenetic outlier strains had differing MLST, antimicrobial resistance and molecular profiles suggestive of capsule switching events. While capsule switch events among S. pneumoniae serotype 22F has been observed, increasing prevalence of S. pneumoniae serotype 22F can be attributed to an evolving homogenous clone expanding nationally through local transmission events.

  6. Phylogenetic variation of Aggregatibacter actinomycetemcomitans serotype e reveals an aberrant distinct evolutionary stable lineage

    NARCIS (Netherlands)

    van der Reijden, Wil A.; Brunner, Jorg; Bosch-Tijhof, Carolien J.; van Trappen, Stefanie; Rijnsburger, Martine C.; de Graaff, Marcel P. W.; van Winkelhoff, Arie J.; Cleenwerck, Ilse; de Vos, Paul

    2010-01-01

    The periodontal pathogen Aggregatibacter actinomycetemcomitans that comprises six serotypes (a-f), is often identified by PCR-based techniques targeting the 16S rRNA gene. In this study, 16S rRNA gene sequence analysis revealed an aberrant cluster of 19 strains within serotype e, denoted as serotype

  7. Fully human monoclonal antibodies from antibody secreting cells after vaccination with Pneumovax®23 are serotype specific and facilitate opsonophagocytosis.

    Science.gov (United States)

    Smith, Kenneth; Muther, Jennifer J; Duke, Angie L; McKee, Emily; Zheng, Nai-Ying; Wilson, Patrick C; James, Judith A

    2013-05-01

    B lymphocyte memory generates antibody-secreting cells (ASCs) that represent a source of protective antibodies that may be exploited for therapeutics. Here we vaccinated four donors with Pneumovax®23 and produced human monoclonal antibodies (hmAbs) from ASCs. We have cloned 137 hmAbs and the specificities of these antibodies encompass 19 of the 23 serotypes in the vaccine, as well as cell wall polysaccharide (CWPS). Although the majority of the antibodies are serotype specific, 12% cross-react with two serotypes. The Pneumovax®23 ASC antibody sequences are highly mutated and clonal, indicating an anamnestic response, even though this was a primary vaccination. Hmabs from 64% of the clonal families facilitate opsonophagocytosis. Although 9% of the total antibodies bind to CWPS impurity in the vaccine, none of these clonal families showed opsonophagocytic activity. Overall, these studies have allowed us to address unanswered questions in the field of human immune responses to polysaccharide vaccines, including the cross-reactivity of individual antibodies between serotypes and the percentage of antibodies that are protective after vaccination with Pneumovax®23. Copyright © 2012 Elsevier GmbH. All rights reserved.

  8. Selective and genetic constraints on pneumococcal serotype switching.

    Directory of Open Access Journals (Sweden)

    Nicholas J Croucher

    2015-03-01

    Full Text Available Streptococcus pneumoniae isolates typically express one of over 90 immunologically distinguishable polysaccharide capsules (serotypes, which can be classified into "serogroups" based on cross-reactivity with certain antibodies. Pneumococci can alter their serotype through recombinations affecting the capsule polysaccharide synthesis (cps locus. Twenty such "serotype switching" events were fully characterised using a collection of 616 whole genome sequences from systematic surveys of pneumococcal carriage. Eleven of these were within-serogroup switches, representing a highly significant (p < 0.0001 enrichment based on the observed serotype distribution. Whereas the recombinations resulting in between-serogroup switches all spanned the entire cps locus, some of those that caused within-serogroup switches did not. However, higher rates of within-serogroup switching could not be fully explained by either more frequent, shorter recombinations, nor by genetic linkage to genes involved in β-lactam resistance. This suggested the observed pattern was a consequence of selection for preserving serogroup. Phenotyping of strains constructed to express different serotypes in common genetic backgrounds was used to test whether genotypes were physiologically adapted to particular serogroups. These data were consistent with epistatic interactions between the cps locus and the rest of the genome that were specific to serotype, but not serogroup, meaning they were unlikely to account for the observed distribution of capsule types. Exclusion of these genetic and physiological hypotheses suggested future work should focus on alternative mechanisms, such as host immunity spanning multiple serotypes within the same serogroup, which might explain the observed pattern.

  9. Virulence of six capsular serotypes of Porphyromonas gingivalis in a mouse model

    NARCIS (Netherlands)

    Laine, ML; van Winkelhoff, AJ

    1998-01-01

    Capsular structures of Porphyromonas gingivalis have been correlated to the pathogenicity in animal models. Six polysaccharide capsular serotypes have recently been described in P. gingivalis. In the present study, virulence of the P. gingivalis strains of the six capsular serotypes was compared

  10. Capsular polysaccharide typing of domestic mastitis-causing Staphylococcus aureus strains and its potential exploration of bovine mastitis vaccine development. I. Capsular polysaccharide typing, isolation and purification of the strains.

    Science.gov (United States)

    Han, H R; Pak, S I; Kang, S W; Jong, W S; Youn, C J

    2000-06-01

    One hundred seven isolates of Staphylococcus aureus from bovine mastitis were investigated for colony morphology in serum-soft agar (SSA), autoagglutination in salt, and capsular serotype. Capsular polysaccharide (CP) was purified and quantified from the extracts of clinical isolates. Overall, 89 isolates (83.2%) were diffuse in the SSA, without any difference in the proportion of diffuse colony between type 5 and type 8 strains. Some strains exhibited compact colonies in the SSA and expressed CP as determined by an enzyme-linked immunosorbent assay, indicating that compact morphology does not exclude encapsulation. The majority of the strains (11/12) showed autoagglutination in the salt aggregation test. The serotype 336 accounted for 46.7% of the isolates followed by serotype 5 (12.1%) and serotype 8 (12.1%). Particularly, twenty-six (24.3%) isolates reacted with two serotypes; 7 for type 8/336 and 19 for type 5/336. Five isolates (4.7%) were nontypeable with monoclonal antibodies specific for CP serotype 5, 8, or 336. The CP concentration in culture supernatants varied with the serotypes, and the total amount of CP produced by cells grown in a liquid medium was much less than that produced by cells grown on a solid medium. The Western blotting indicated that the CP bands of S. aureus serotype 5 and 8 were ranged in the molecular mass of 58-84 kilodalton (kDa), with additional bands in the region of approximately >/= 48 or

  11. [Increase in the incidence of invasive pneumococcal disease caused by serotype 19A prior to the implementation of the expanded pneumococcal vaccines].

    Science.gov (United States)

    González Martínez, F; Saavedra Lozano, J; Navarro Gómez, M L; Santos Sebastián, M M; Rodríguez Fernández, R; González Sánchez, M; Hernández-Sampelayo Matos, T

    2013-11-01

    To describe the epidemiology, clinical syndromes and microbiological characteristics of serotype 19A as the main cause of invasive pneumococcal disease (IPD) in children admitted to a tertiary hospital in Spain. A retrospective (1998-2004) and prospective (2005-2009) study was conducted on children with IPD produced by serotype 19A. The study was divided into three periods (P): P1 (1998-2001) when PCV7 had not been commercialized; P2 (2002-2005) with 40% vaccine coverage among children; and P3 (2006-2009) when the vaccine was added to the Childhood Immunization Schedule in Madrid. A total of 155 isolates of Streptococcus pneumoniae (SP) producing IPD were analysed, with 21 of them being serotype 19A (14%). An increased prevalence of serotype 19A was found: 2/45 cases (4.4%) in P1, 3/41 cases (7.3%) in P2 and 16/69 cases (23.2%) in P3. It occurred mostly in children younger than 2 years (16/21; 76%). This serotype was the main cause of meningitis (5/20; 25%), pleural empyema (3/22; 14%) and bacteraemic mastoiditis (2/4; 50%). Thirteen isolates (61.5%) had an MIC ≥ 0.12μ/ml for penicillin in extra-meningeal infections, and 3 of the 5 isolates causing meningitis (60%) had an MIC ≥ 1μ/ml for cefotaxime. Serotype 19A was the main causal agent of IPD in the PCV7 era (P3), with high antibiotic resistance rates. This serotype was responsible for all types of IPD, being the main cause of meningitis. Copyright © 2012 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  12. Clonal relationship of recent invasive Haemophilus influenzae serotype f isolates from Denmark and the United States

    DEFF Research Database (Denmark)

    Bruun, B; Gahrn-Hansen, B; Westh, H

    2004-01-01

    Surveillance performed after the introduction of general Haemophilus influenzae serotype b (Hib) vaccination in Denmark identified 13 cases of invasive bacteraemic H. influenzae serotype f (Hif) disease in adults over a period of 7 years. Bacteraemic respiratory tract infections accounted for 61...... sequences. Multilocus enzyme electrophoresis typing revealed that recent Danish and American isolates belonged to a single Hif clone, which may be undergoing expansion. The need for accurate serotyping of H. influenzae to enable reliable monitoring for Hib replacement by other capsular types is emphasized....

  13. Establishment of a Molecular Serotyping Scheme and a Multiplexed Luminex-Based Array for Enterobacter aerogenes.

    Science.gov (United States)

    Guo, Xi; Wang, Min; Wang, Lu; Wang, Yao; Chen, Tingting; Wu, Pan; Chen, Min; Liu, Bin; Feng, Lu

    2018-01-01

    Serotyping based on surface polysaccharide antigens is important for the clinical detection and epidemiological surveillance of pathogens. Polysaccharide gene clusters (PSgcs) are typically responsible for the diversity of bacterial surface polysaccharides. Through whole-genome sequencing and analysis, eight putative PSgc types were identified in 23 Enterobacter aerogenes strains from several geographic areas, allowing us to present the first molecular serotyping system for E. aerogenes . A conventional antigenic scheme was also established and correlated well with the molecular serotyping system that was based on PSgc genetic variation, indicating that PSgc-based molecular typing and immunological serology provide equally valid results. Further, a multiplex Luminex-based array was developed, and a double-blind test was conducted with 97 clinical specimens from Shanghai, China, to validate our array. The results of these analyses indicated that strains containing PSgc4 and PSgc7 comprised the predominant groups. We then examined 86 publicly available E. aerogenes strain genomes and identified an additional seven novel PSgc types, with PSgc10 being the most abundant type. In total, our study identified 15 PSgc types in E. aerogenes , providing the basis for a molecular serotyping scheme. From these results, differing epidemic patterns were identified between strains that were predominant in different regions. Our study highlights the feasibility and reliability of a serotyping system based on PSgc diversity, and for the first time, presents a molecular serotyping system, as well as an antigenic scheme for E. aerogenes , providing the basis for molecular diagnostics and epidemiological surveillance of this important emerging pathogen.

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

    International Nuclear Information System (INIS)

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

    1986-01-01

    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 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

  15. Streptococcus pneumoniae from Palestinian nasopharyngeal carriers: serotype distribution and antimicrobial resistance.

    Directory of Open Access Journals (Sweden)

    Abedelmajeed Nasereddin

    Full Text Available Infections of Streptococcus pneumoniae in children can be prevented by vaccination; left untreated, they cause high morbidity and fatalities. This study aimed at determining the nasopharyngeal carrier rates, serotype distribution and antimicrobial resistance patterns of S. pneumoniae in healthy Palestinian children under age two prior to the full introduction of the pneumococcal 7-valent conjugate vaccine (PCV7, which was originally introduced into Palestine in a pilot trial in September, 2010. In a cross sectional study, nasopharyngeal specimens were collected from 397 healthy children from different Palestinian districts between the beginning of November 2012 to the end of January 2013. Samples were inoculated into blood agar and suspected colonies were examined by amplifying the pneumococcal-specific autolysin gene using a real-time PCR. Serotypes were identified by a PCR that incorporated different sets of specific primers. Antimicrobial susceptibility was measured by disk diffusion and MIC methods. The resulting carrier rate of Streptococcus pneumoniae was 55.7% (221/397. The main serotypes were PCV7 serotypes 19F (12.2%, 23F (9.0%, 6B (8.6% and 14 (4% and PCV13 serotypes 6A (13.6% and 19A (4.1%. Notably, serotype 6A, not included in the pilot trial (PCV7 vaccine, was the most prevalent. Resistance to more than two drugs was observed for bacteria from 34.1% of the children (72/211 while 22.3% (47/211 carried bacteria were susceptible to all tested antibiotics. All the isolates were sensitive to cefotaxime and vancomycin. Any or all of these might impinge on the type and efficacy of the pneumococcal conjugate vaccines and antibiotics to be used for prevention and treatment of pneumococcal disease in the country.

  16. Group B streptococcus serotype prevalence in reproductive-age women at a tertiary care military medical center relative to global serotype distribution

    Directory of Open Access Journals (Sweden)

    Williams Julie

    2010-11-01

    Full Text Available Abstract Background Group B Streptococcus (GBS serotype (Ia, Ib, II-IX correlates with pathogen virulence and clinical prognosis. Epidemiological studies of seroprevalence are an important metric for determining the proportion of serotypes in a given population. The purpose of this study was to evaluate the prevalence of individual GBS serotypes at Madigan Healthcare System (Madigan, the largest military tertiary healthcare facility in the Pacific Northwestern United States, and to compare seroprevalences with international locations. Methods To determine serotype distribution at Madigan, we obtained GBS isolates from standard-of-care anogenital swabs from 207 women of indeterminate gravidity between ages 18-40 during a five month interval. Serotype was determined using a recently described molecular method of polymerase chain reaction by capsular polysaccharide synthesis (cps genes associated with pathogen virulence. Results Serotypes Ia, III, and V were the most prevalent (28%, 27%, and 17%, respectively. A systematic review of global GBS seroprevalence, meta-analysis, and statistical comparison revealed strikingly similar serodistibution at Madigan relative to civilian-sector populations in Canada and the United States. Serotype Ia was the only serotype consistently higher in North American populations relative to other geographic regions (p Conclusion This study establishes PCR-based serotyping as a viable strategy for GBS epidemiological surveillance. Our results suggest that GBS seroprevalence remains stable in North America over the past two decades.

  17. Immunogenicity of simultaneous versus sequential administration of a 23-valent pneumococcal polysaccharide vaccine and a quadrivalent influenza vaccine in older individuals: A randomized, open-label, non-inferiority trial.

    Science.gov (United States)

    Nakashima, Kei; Aoshima, Masahiro; Ohfuji, Satoko; Yamawaki, Satoshi; Nemoto, Masahiro; Hasegawa, Shinya; Noma, Satoshi; Misawa, Masafumi; Hosokawa, Naoto; Yaegashi, Makito; Otsuka, Yoshihito

    2018-03-21

    It is unclear whether simultaneous administration of a 23-valent pneumococcal polysaccharide vaccine (PPSV23) and a quadrivalent influenza vaccine (QIV) produces immunogenicity in older individuals. This study tested the hypothesis that the pneumococcal antibody response elicited by simultaneous administration of PPSV23 and QIV in older individuals is not inferior to that elicited by sequential administration of PPSV23 and QIV. We performed a single-center, randomized, open-label, non-inferiority trial comprising 162 adults aged ≥65 years randomly assigned to either the simultaneous (simultaneous injections of PPSV23 and QIV) or sequential (control; PPSV23 injected 2 weeks after QIV vaccination) groups. Pneumococcal immunoglobulin G (IgG) titers of serotypes 23F, 3, 4, 6B, 14, and 19A were assessed. The primary endpoint was the serotype 23F response rate (a ≥2-fold increase in IgG concentrations 4-6 weeks after PPSV23 vaccination). With the non-inferiority margin set at 20% fewer patients, the response rate of serotype 23F in the simultaneous group (77.8%) was not inferior to that of the sequential group (77.6%; difference, 0.1%; 90% confidence interval, -10.8% to 11.1%). None of the pneumococcal IgG serotype titers were significantly different between the groups 4-6 weeks after vaccination. Simultaneous administration did not show a significant decrease in seroprotection odds ratios for H1N1, H3N2, or B/Phuket influenza strains other than B/Texas. Additionally, simultaneous administration did not increase adverse reactions. Hence, simultaneous administration of PPSV23 and QIV shows an acceptable immunogenicity that is comparable to sequential administration without an increase in adverse reactions. (This study was registered with ClinicalTrials.gov [NCT02592486]).

  18. Multiplex PCR to determine Streptococcus pneumoniae serotypes causing otitis media in the Republic of Ireland with further characterisation of antimicrobial susceptibilities and genotypes.

    LENUS (Irish Health Repository)

    Vickers, I

    2011-03-01

    The purpose of this study was to determine the serotypes, genotypes and antimicrobial susceptibilities of Streptococcus pneumoniae causing otitis media (OM) in children in Dublin, Ireland. S. pneumoniae isolates (n = 28) from spontaneously discharging OM were studied. Serotyping was performed using a previously undescribed multiplex polymerase chain reaction (PCR) scheme in combination with serological methods. Multilocus sequence typing (MLST) was performed using standard procedures. Antimicrobial susceptibility testing was performed using the Etest method. Fourteen different S. pneumoniae serotypes were identified. The five most common serotypes were 3, 19F, 19A, 14 and 6A, which accounted for 68% of all infections. The 7-valent pneumococcal conjugate vaccine (PCV7), 10-valent pneumococcal conjugate vaccine (PHiD-CV) and 13-valent pneumococcal conjugate vaccine (PCV13) provided potential coverages of 43%, 46% and 86%, respectively. Reduced susceptibility to penicillin was evident for 25% of isolates and was associated with serotypes 14, 19A, 19F and 9V. A total of 21 different sequence types (STs) were identified. Pneumococcal Molecular Epidemiology Network (PMEN) clones or their variants represented 54% (15\\/28) of all isolates. Continued monitoring and characterisation of S. pneumoniae causing OM in Ireland is warranted in order to guide future vaccine and treatment policies.

  19. Study of 19F and 19Ne mirror nuclei

    International Nuclear Information System (INIS)

    Lebrun, Claude.

    1976-01-01

    The electromagnetic properties of the mirror nuclei 19 F and 19 Ne were studied using the 18 O(d,nγ) 19 F, 17 O( 3 He,nγ) 19 Ne and 19 F(p,nγ) 19 Ne reactions. Lifetimes of 8 levels in 19 F and 11 levels in 19 Ne have been measured using the Doppler shift attenuation method. Weak and strong components of M 1 , E 1 and E 2 transition strengths are compared with shell model predictions. M 1 and E 2 transition strengths of conjugated nuclei (A=18 to A=34) are compiled and compared with wide configuration space shell models [fr

  20. Serological characterization of Actinobacillus pleuropneumoniae biotype 1 strains antigenically related to both serotypes 2 and 7

    DEFF Research Database (Denmark)

    Nielsen, R.; Andresen, Lars Ole; Plambeck, Tamara

    1996-01-01

    Nine Danish Actinobacillus pleuropneumoniae biotype 1 isolates were shown by latex agglutination and indirect haemagglutination to possess capsular polysaccharide epitopes identical to those of serotype 2 strain 1536 (reference strain of serotype 2) and strain 4226 (Danish serotype 2 strain). Imm...... in the LPS of strains 1536 and 7317 were revealed. Since an antigenic determinant specific for the 9 isolates could not be demonstrated with the methods used, the strains are proposed to be designated K2:O7....

  1. Pediatric invasive pneumococcal disease caused by vaccine serotypes following the introduction of conjugate vaccination in Denmark

    DEFF Research Database (Denmark)

    Harboe, Zitta B; Valentiner-Branth, Palle; Ingels, Helene

    2013-01-01

    A seven-valent pneumococcal conjugate vaccine (PCV7) was introduced in the Danish childhood immunization program (2+1 schedule) in October 2007, followed by PCV13 starting from April 2010. The nationwide incidence of IPD among children younger than 5 years nearly halved after the introduction...... of children suspected to present with a vaccine failure. The period between April 19 and December 31, 2010 was considered a PCV7/PCV13 transitional period, where both vaccines were offered. We identified 45 episodes of IPD caused by a PCV7 serotype (23% of the total number) and 105 (55%) caused by one...... of the 6 additional serotypes in PCV13. Ten children had received at least one PCV7 dose before the onset of IPD caused by a PCV7 serotype. Seven children were considered to be incompletely vaccinated before IPD, but only three cases fulfilled the criteria of vaccine failure (caused by serotypes 14, 19F...

  2. A structural investigation of the capsular antigens of some Klebsiella and E. coli serotypes

    International Nuclear Information System (INIS)

    Parolis, L.A.S.

    1985-11-01

    The work described in this thesis forms part of a program concerned with the study of exocellular capsular polysaccharides of some Enterobacteriaceae. 1 H- and 13 C-n.m.r. spectroscopy have been used in this study. Klebsiella and Escherichia coli are of interest because they are often pathogenic to man; E. coli are commensal bacteria as well as opportunistic pathogens. The bacterial capsule is the first line of defence of the bacterial cell against attack by the host's immunological defences and administered antibiotics, and thus knowledge of its composition and characteristics is of importance in devising ways of combating infection by these organisms. The structure of the capsular polysaccharide has been investigated employing a combination of chemical and spectroscopic methods. Several oligo-saccharides were isolated and characterized by high resolution 1 H-n.m.r. spectroscopy and methylation analysis. The E. coli group of bacteria possesses seventy-four recognized polysaccharide capsules and the structures of approximately twenty percent of these have been reported. The emphasis of this research group is centered on the elucidation of the structures of E. coli capsules. The acidic capsular polysaccharide isolated from E. coli K9 has been investigated using the techniques of methylation analysis periodate oxidation, bacteriophage degradation and n.m.r. spectroscopy. This thesis however represents a transition period in the study of Enterobacteriaceae capsular polysaccharides and so includes the structure elucidation of two Klebsiella polysaccharides, that of the K14 and K68 serotypes, and one E. coli polysaccharide, that of the K9 serotype. Bacteriophage-borne enzyme degradations of Klebsiella K14 and E. coli K9 polysaccharides have been performed and are presented. The thesis also includes a comparative study of the 0-specific side-chains of the lipo-polysaccharides of E. coli 09 and 09a serogroups

  3. [Quantitive variation of polysaccharides and alcohol-soluble extracts in F1 generation of Dendrobium officinale].

    Science.gov (United States)

    Zhang, Xiao-Ling; Liu, Jing-Jing; Wu, Ling-Shang; Si, Jin-Ping; Guo, Ying-Ying; Yu, Jie; Wang, Lin-Hua

    2013-11-01

    Using phenol-sulfuric acid method and hot-dip method of alcohol-soluble extracts, the contents of polysaccharides and alcohol-soluble extracts in 11 F1 generations of Dendrobium officinale were determined. The results showed that the polysaccharides contents in samples collected in May and February were 32.89%-43.07% and 25.77%-35.25%, respectively, while the extracts contents were 2.81%-4.85% and 7.90%-17.40%, respectively. They were significantly different among families. The content of polysaccharides in offspring could be significantly improved by hybridization between parents with low and high polysaccharides contents, and the hybrid vigor was obvious. Cross breeding was an effective way for breeding new varieties with higher polysaccharides contents. Harvest time would significantly affect the contents of polysaccharides and alcohol-soluble extracts. The contents of polysaccharides in families collected in May were higher than those of polysaccharides in families collected in February, but the extracts content had the opposite variation. The extents of quantitative variation of polysaccharides and alcohol-soluble extracts were different among families, and each family had its own rules. It would be significant in giving full play to their role as the excellent varieties and increasing effectiveness by studying on the quantitative accumulation regularity of polysaccharides and alcohol-soluble extracts in superior families (varieties) of D. officinale to determine the best harvesting time.

  4. Capsular Polysaccharide Expression in Commensal Streptococcus Species

    DEFF Research Database (Denmark)

    Skov Sørensen, Uffe B; Yao, Kaihu; Yang, Yonghong

    2016-01-01

    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....... 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...... of Streptococcus pneumoniae and is the basis for successful vaccines against infections caused by this important pathogen. Contrasting with previous assumptions, this study showed that expression of capsular polysaccharides by the same genetic mechanisms is a general property of closely related species...

  5. [Emergence of invasive pneumococcal disease caused by non-vaccine serotypes in the era of the 7-valent conjugate vaccine].

    Science.gov (United States)

    González Martínez, F; Navarro Gómez, M L; Saavedra Lozano, J; Santos Sebastián, M M; Rodríguez Fernández, R; González Sanchéz, M; Cercenado Mansilla, E; Hernández-Sampelayo Matos, T

    2014-03-01

    There has been an increased incidence in invasive pneumococcal disease (IPD) produced by non-vaccine serotype (NVS) of Streptococcus pneumoniae after the introduction of PCV7. Our objective was to describe the epidemiological, clinical and microbiological characteristics of IPD caused by NVS in a tertiary hospital in Madrid. Retrospective (1998-2004) and prospective (2005-2009) study evaluating IPD caused by NVS in children. The study was divided into three periods: P1 (1998-2001) when PCV7 was not commercialized; P2 (2002-2005) with 40% vaccine coverage among children; and P3 (2006-2009) when the vaccine was added to the Childhood Immunization Schedule in Madrid. We analyzed 155 cases of IPD. One hundred and fifty of these isolates were serotyped (100 were NVS). There was an increase in the prevalence of IPD from P1 (31%) to P2 (54%) and P3 (91%). The most relevant emerging serotypes were 19A, 7F, 1, 5, 3 and 15C. The most significant clinical syndromes produced by some specific serotypes were as follows: lower respiratory tract infection (LRTI) by serotypes 1, 3, 5 and 15C; LRTI, primary bacteremia and meningitis by serotype 19A; and primary bacteremia by serotype 7F (66%). The large majority (83.8%) of NVS were sensitive to penicillin. There has been an increased prevalence of IPD caused by NVS since the introduction of PCV7. These changes should prompt the introduction of new pneumococcal vaccines, which include most of the NVS, in the childhood immunization calendar to prevent IPD in children. Copyright © 2012 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  6. Serotype distribution and antibiotic susceptibility of Streptococcus pneumoniae strains in the south of Tunisia: A five-year study (2012–2016 of pediatric and adult populations

    Directory of Open Access Journals (Sweden)

    Sonia Ktari

    2017-12-01

    Full Text Available Objectives: To analyze the serotype distribution of Streptococcus pneumoniae clinical isolates collected in the south of Tunisia over a 5-year period in different age groups and to assess their antimicrobial susceptibility patterns. Methods: A total of 305 non-duplicate S. pneumoniae isolates were collected between January 2012 and December 2016 at the university hospital in Sfax, Tunisia. All isolates were serotyped by multiplex PCR. The antibiotic susceptibility of all isolates was determined using the disk diffusion test or Etest assay. Results: Among the 305 pneumococcal isolates, 76 (24.9% were invasive and 229 (75.1% were non-invasive. The most common serotypes were 19F (20%, 14 (16.7%, 3 (9.2%, 23F (7.5%, 19A (5.9%, and 6B (5.9%. Potential immunization coverage rates for pneumococcal conjugate vaccines PCV7, PCV10, and PCV13 were 58%, 59.3%, and 78.7%, respectively. Three-quarters (75.3% of pneumococcal isolates were non-susceptible to penicillin. The resistance rate to erythromycin was 71.4%. Only two isolates were resistant to levofloxacin. Conclusions: 19F and 14 were the most prevalent serotypes in the south of Tunisia. The inclusion of a PCV in the immunization program could be useful for reducing the burden of pneumococcal diseases. The high resistance rate to penicillin and macrolides is alarming. Prudent use of antibiotics is crucial to prevent the selection of multidrug-resistant pneumococci. Keywords: Streptococcus pneumoniae, Antibiotic, Serotype, PCV, Tunisia

  7. Protection against Streptococcus suis Serotype 2 Infection Using a Capsular Polysaccharide Glycoconjugate Vaccine

    Science.gov (United States)

    Calzas, Cynthia; Shiao, Tze Chieh; Neubauer, Axel; Kempker, Jennifer; Roy, René; Gottschalk, Marcelo

    2016-01-01

    Streptococcus suis serotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. Despite decades of research for an efficient vaccine, none is currently available. Based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-CPS) IgG antibodies. In this work, glycoconjugate prototypes were prepared by coupling S. suis type 2 CPS to tetanus toxoid, and the immunological features of the postconjugation preparations were evaluated in vivo. In mice, experiments evaluating three different adjuvants showed that CpG oligodeoxyribonucleotide (ODN) induces very low levels of anti-CPS IgM antibodies, while the emulsifying adjuvants Stimune and TiterMax Gold both induced high levels of IgGs and IgM. Dose-response trials comparing free CPS with the conjugate vaccine showed that free CPS is nonimmunogenic independently of the dose used, while 25 μg of the conjugate preparation was optimal in inducing high levels of anti-CPS IgGs postboost. With an opsonophagocytosis assay using murine whole blood, sera from immunized mice showed functional activity. Finally, the conjugate vaccine showed immunogenicity and induced protection in a swine challenge model. When conjugated and administered with emulsifying adjuvants, S. suis type 2 CPS is able to induce potent IgM and isotype-switched IgGs in mice and pigs, yielding functional activity in vitro and protection against a lethal challenge in vivo, all features of a T cell-dependent response. This study represents a proof of concept for the potential of glycoconjugate vaccines in veterinary medicine applications against invasive bacterial infections. PMID:27113360

  8. The use of oligonucleotide probes for meningococcal serotype characterization

    Directory of Open Access Journals (Sweden)

    SACCHI Claudio Tavares

    1998-01-01

    Full Text Available In the present study we examine the potential use of oligonucleotide probes to characterize Neisseria meningitidis serotypes without the use of monoclonal antibodies (MAbs. Antigenic diversity on PorB protein forms the bases of serotyping method. However, the current panel of MAbs underestimated, by at least 50% the PorB variability, presumably because reagents for several PorB variable regions (VRs are lacking, or because a number of VR variants are not recognized by serotype-defining MAbs12. We analyzed the use of oligonucleotide probes to characterize serotype 10 and serotype 19 of N. meningitidis. The porB gene sequence for the prototype strain of serotype 10 was determined, aligned with 7 other porB sequences from different serotypes, and analysis of individual VRs were performed. The results of DNA probes 21U (VR1-A and 615U (VR3-B used against 72 N. meningitidis strains confirm that VR1 type A and VR3 type B encode epitopes for serotype-defined MAbs 19 and 10, respectively. The use of probes for characterizing serotypes possible can type 100% of the PorB VR diversity. It is a simple and rapid method specially useful for analysis of large number of samples.

  9. Genomic Characterization of Flavobacterium psychrophilum Serotypes and Development of a Multiplex PCR-Based Serotyping Scheme

    Directory of Open Access Journals (Sweden)

    Tatiana Rochat

    2017-09-01

    Full Text Available Flavobacterium psychrophilum is a devastating bacterial pathogen of salmonids reared in freshwater worldwide. So far, serological diversity between isolates has been described but the underlying molecular factors remain unknown. By combining complete genome sequence analysis and the serotyping method proposed by Lorenzen and Olesen (1997 for a set of 34 strains, we identified key molecular determinants of the serotypes. This knowledge allowed us to develop a robust multiplex PCR-based serotyping scheme, which was applied to 244 bacterial isolates. The results revealed a striking association between PCR-serotype and fish host species and illustrate the use of this approach as a simple and cost-effective method for the determination of F. psychrophilum serogroups. PCR-based serotyping could be a useful tool in a range of applications such as disease surveillance, selection of salmonids for bacterial coldwater disease resistance and future vaccine formulation.

  10. Determination of Serotypes and Antibiotic Resistance in Streptococcus Pneumoniae

    Directory of Open Access Journals (Sweden)

    Deniz Akgun Karapinar

    2016-01-01

    Full Text Available Aim: In this study, the distribution of serogroup/serotype and antibiotic susceptibility testing of Streptococcus pneumoniae strains, recovered from pediatric and adult patients were evaluated. Material and Method: A total of 80 clinical isolates recovered from 19 pediatric and 61 adult patients were performed by latex aglutination method and antibiotic susceptibility tests in Istanbul University, Istanbul Faculty of Medicine, Medical Microbiology Laboratories. Results: Sixty-two strains (76 %, were serogroup/serotyped and 18 (23 % strains couldn%u2019t serogroup/serotyped. The most frequent identified serogroups were 19, 14, 23, 6, 4 in pediatrics, and 3, 19, 23 and 9 in adults. In adults, serogroups 3, 9, 5, 8, 18, 1, 15 were determined, but these serogroups weren%u2019t found in pediatrics. Vaccine serotypes rates were found as 53 % in pediatric and as 85 % in adults. The serogroups 2, 7, 10, 11, 12, 17, 20, 22, 33 were not detected, which are available in vaccine serotypes. Only 1 (1 % strain was found to exhibit low level resistance to penicillin and high level resistance wasn%u2019t found in any strain. Resistant results for trimethoprim-sulfamethoxazole, erythromycin, chloramphenicol and ofloxacin were found as 45 (56 %, 22 (27.5 %, 7 (9 %, 2 (2.5 %, respectively. All strains were found susceptible to vancomycin, linezolid and levofloxacin. The most resistant serogroups were 19, 23, 9 and 14 in the tested antibiotics. Multidrug resistance was found in 9 (11 % strains and these strains were found as serogroups 19, 23, 9, 6 and 14. Discussion: The epidemiological studies are important that the distribution of serotype and antibiotic resistance vary depending on many factors like age, and geographic region.

  11. Differential cytokine expression by human dendritic cells in response to different Porphyromonas gingivalis capsular serotypes

    NARCIS (Netherlands)

    Vernal, Rolando; León, Rubén; Silva, Augusto; van Winkelhoff, Arie J; Garcia-Sanz, Jose A; Sanz, Mariano

    2009-01-01

    AIM: Capsular polysaccharides play an important role in the virulence of Gram-positive and Gram-negative bacteria. In Porphyromonas gingivalis, six serotypes have been described based on capsular antigenicity and its pathogenicity has been correlated both in vitro and in animal models. This study

  12. Dominance of multidrug-resistant Denmark(14)-32 (ST230) clone among Streptococcus pneumoniae serotype 19A isolates causing pneumococcal disease in Bulgaria from 1992 to 2013.

    Science.gov (United States)

    Setchanova, Lena Petrova; Alexandrova, Alexandra; Dacheva, Daniela; Mitov, Ivan; Kaneva, Radka; Mitev, Vanio

    2015-02-01

    A pneumococcal conjugate vaccine (PCV10) was introduced in Bulgarian national immunization program since April 2010. Clonal composition based on pulsed-field gel electrophoresis and multilocus sequence typing genotyping of 52 serotype 19A Streptococcus pneumoniae isolates was analyzed. These were invasive and respiratory isolates collected between 1992 and 2013 from both children (78.8% clone. The most frequent sequence type (ST) was ST230 (48.1%) and together with four other closely related STs (15.4%), belonging to ST1611, ST276, ST7466, and ST2013, which were single- and double-locus variants; they were included in the main CC230. The disappearance of highly drug-resistant ST663 clone and emergence of new clones as CC320 and CC199 was also observed among the rest 19A isolates. A comparison of clonal composition between invasive and noninvasive isolates did not show a great genetic diversity among both kinds of isolates. Continuous surveillance of serotype 19A population following the introduction of PCV10 is essential to evaluate the impact of the vaccine on the epidemiology of this serotype.

  13. Development of a Colloidal Gold-Based Immunochromatographic Strip for Rapid Detection of Klebsiella pneumoniae Serotypes K1 and K2.

    Science.gov (United States)

    Siu, L Kristopher; Tsai, Yu-Kuo; Lin, Jung-Chung; Chen, Te-Li; Fung, Chang-Phone; Chang, Feng-Yee

    2016-12-01

    In this study, a novel colloidal gold-based immunochromatographic strip (ICS) containing anti-Klebsiella pneumoniae capsular polysaccharide polyclonal antibodies was developed to specifically detect K. pneumoniae serotypes K1 and K2. Capsular polysaccharide K1 and K2 antigens were first used to produce polyclonal anti-K1 and anti-K2 antibodies. Reference strains with different serotypes, nontypeable K. pneumoniae strains, and other bacterial species were then used to assess the sensitivity and specificity of these test strips. The detection limit was found to be 10 5 CFU, and the ICSs were stable for 6 months when stored at room temperature. No false-positive or false-negative results were observed, and equivalent results were obtained compared to those of more conventional test methods, such as PCR or serum agglutination. In conclusion, the ICS developed here requires no technical expertise and allows for the specific, rapid, and simultaneous detection of K. pneumoniae serotypes K1 and K2. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  14. Outer membrane protein complex of Meningococcus enhances the antipolysaccharide antibody response to pneumococcal polysaccharide-CRM₁₉₇ conjugate vaccine.

    Science.gov (United States)

    Lai, Zengzu; Schreiber, John R

    2011-05-01

    Bacterial polysaccharides (PS) are T cell-independent antigens that do not induce immunologic memory and are poor immunogens in infants. Conjugate vaccines in which the PS is covalently linked to a carrier protein have enhanced immunogenicity that resembles that of T cell-dependent antigens. The Haemophilus influenzae type b (Hib) conjugate vaccine, which uses the outer membrane protein complex (OMPC) from meningococcus as a carrier protein, elicits protective levels of anti-capsular PS antibody (Ab) after a single dose, in contrast to other conjugate vaccines, which require multiple doses. We have previously shown that OMPC robustly engages Toll-like receptor 2 (TLR2) and enhances the early anti-Hib PS Ab titer associated with an increase in TLR2-mediated induction of cytokines. We now show that the addition of OMPC to the 7-valent pneumococcal PS-CRM₁₉₇ conjugate vaccine during immunization significantly increases the anti-PS IgG and IgM responses to most serotypes of pneumococcus contained in the vaccine. The addition of OMPC also increased the likelihood of anti-PS IgG3 production against serotypes 4, 6B, 9V, 18C, 19F, and 23F. Splenocytes from mice who had received OMPC with the pneumococcal conjugate vaccine produced significantly more interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) than splenocytes from mice who received phosphate-buffered saline (PBS) plus the conjugate vaccine. We conclude that OMPC enhances the anti-PS Ab response to pneumococcal PS-CRM₁₉₇ conjugate vaccine, an effect associated with a distinct change in cytokine profile. It may be possible to reduce the number of conjugate vaccine doses required to achieve protective Ab levels by priming with adjuvants that are TLR2 ligands.

  15. Septic arthritis of shoeulder caused by Streptococcus pneumoniae serotype 23F in a female infant. Report of a case

    Directory of Open Access Journals (Sweden)

    Flores Nava Gerardo

    2014-07-01

    Full Text Available We present the case of a female infant previously vaccinated against Streptococcus pneumoniae who developed a septic arthritis in the right shoulder. An artrothomy was performed. The culture of the sy- novial fluid was positive for serotype 23F Streptococcus pneumonia.

  16. Multidrug resistance among different serotypes of clinical Salmonella isolates in Taiwan

    DEFF Research Database (Denmark)

    Lauderdale, T. L.; Aarestrup, Frank Møller; Chen, P. C.

    2006-01-01

    (41%) and was highly prevalent in Salmonella enterica serotype Typhimurium (72.7%, 176/242) the most common serotype. Additional resistance to trimethoprim was present in 155 (19.4% overall) of the ACSSuT R-type isolates from several serotypes. Reduced susceptibility to fluoroquinolone (FQ...... multiresistant to other antimicrobials. Studies are needed to determine the sources of different multidrug-resistant serotypes. Continued national surveillance is underway to monitor changes in resistance trends and to detect further emergence of resistant Salmonella serotypes in Taiwan. (c) 2006 Elsevier Inc...

  17. Transverse excitations of 19F

    International Nuclear Information System (INIS)

    Donne, A.J.H.

    1985-01-01

    In this thesis aspects of the structure of the nucleus 19 F are discussed as a result of transverse electron-scattering experiments, with emphasis on the ground state. The magnetization distribution of this state has been obtained from the measurement of electrons scattered from 19 F at backward angles. An introduction to the electron-scattering formalism is presented briefly together with the interpretation of electron-scattering results in terms of the nuclear shell model. The experimental apparatus for the measurement of electron scattering through an angle of 180 0 is described. This instrumentation has been installed in the low-energy facility (LEF) at NIKHEF-K. Simultaneously with the study of the magnetic ground state distribution of 19 F, also excited states of this nucleus up to an energy of 4.4 MeV have been investigated, mainly from data obtained in the EMIN station. Also for these states, the shell-model calculations have been the guide to determine their structure. (Auth.)

  18. Detection sensitivity of fluorine in dental enamel through the 19F(p,psup(')γ)19F reaction

    International Nuclear Information System (INIS)

    Papper, C.S.; Chittleborough, G.; Kennett, S.R.; Chaudhri, M.A.

    1978-01-01

    The total cross sections for production of 109 and 197 keV gamma rays in the reaction 19 F(p,psup(')γ) 19 F have been measured, over a range of energies up to 4.3 MeV. From these cross sections, the thick detection sensitivities for a uniform distribution of fluorine in dental enamel have been calculated

  19. NbF5 and TaF5: Assignment of 19F NMR resonances and chemical bond analysis from GIPAW calculations

    International Nuclear Information System (INIS)

    Biswal, Mamata; Body, Monique; Legein, Christophe; Sadoc, Aymeric; Boucher, Florent

    2013-01-01

    The 19 F isotropic chemical shifts (δ iso ) of two isomorphic compounds, NbF 5 and TaF 5 , which involve six nonequivalent fluorine sites, have been experimentally determined from the reconstruction of 1D 19 F MAS NMR spectra. In parallel, the corresponding 19 F chemical shielding tensors have been calculated using the GIPAW method for both experimental and DFT-optimized structures. Furthermore, the [M 4 F 20 ] units of NbF 5 and TaF 5 being held together by van der Waals interactions, the relevance of Grimme corrections to the DFT optimization processes has been evaluated. However, the semi-empirical dispersion correction term introduced by such a method does not show any significant improvement. Nonetheless, a complete and convincing assignment of the 19 F NMR lines of NbF 5 and TaF 5 is obtained, ensured by the linearity between experimental 19 F δ iso values and calculated 19 F isotropic chemical shielding σ iso values. The effects of the geometry optimizations have been carefully analyzed, confirming among other matters, the inaccuracy of the experimental structure of NbF 5 . The relationships between the fluorine chemical shifts, the nature of the fluorine atoms (bridging or terminal), the position of the terminal ones (opposite or perpendicular to the bridging ones), the fluorine charges, the ionicity and the length of the M–F bonds have been established. Additionally, for three of the 19 F NMR lines of NbF 5 , distorted multiplets, arising from 1 J-coupling and residual dipolar coupling between the 19 F and 93 Nb nuclei, were simulated yielding to values of 93 Nb– 19 F 1 J-coupling for the corresponding fluorine sites. - Graphical abstract: The complete assignment of the 19 F NMR lines of NbF 5 and TaF 5 allow establishing relationships between the 19 F δ iso values, the nature of the fluorine atoms (bridging or terminal), the position of the terminal ones (opposite or perpendicular to the bridging ones), the fluorine charges, the ionicity and the

  20. Antidiabetic activity of Ganoderma lucidum polysaccharides F31 down-regulated hepatic glucose regulatory enzymes in diabetic mice.

    Science.gov (United States)

    Xiao, Chun; Wu, Qingping; Zhang, Jumei; Xie, Yizhen; Cai, Wen; Tan, Jianbin

    2017-01-20

    Ganoderma lucidum (Lin Zhi) has been used to treat diabetes in Chinese folk for centuries. Our laboratory previously demonstrated that Ganoderma lucidum polysaccharides (GLPs) had hypoglycemic effects in diabetic mice. Our aim was to identify the main bioactives in GLPs and corresponding mechanism of action. Four polysaccharide-enriched fraction were isolated from GLPs and the antidiabetic activities were evaluated by type 2 diabetic mice. Fasting serum glucose (FSG), fasting serum insulin (FSI) and epididymal fat/BW ratio were measured at the end of the experiment. In liver, the mRNA levels of hepatic glucose regulatory enzymes were determined by quantitative polymerase chain reaction (qPCR) and the protein levels of phospho-AMP-activated protein kinase (p-AMPK)/AMPK were determined by western blotting test. In epididymal fat tissue, the mRNA and protein levels GLUT4, resistin, fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC1) were determined by qPCR and immuno-histochemistry. The structure of polysaccharide F31 was obtained from GPC, FTIR NMR and GC-MS spectroscopy, RESULTS: F31 significantly decreased FSG (P<0.05), FSI and epididymal fat/BW ratio (P<0.01). In liver, F31 decreased the mRNA levels of hepatic glucose regulatory enzymes, and up-regulated the ratio of phospho-AMP-activated protein kinase (p-AMPK)/AMPK. In epididymal fat tissue, F31 increased the mRNA levels of GLUT4 but decreased fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC1) and resistin. Immuno-histochemistry results revealed F31 increased the protein levels of GLUT4 and decreased resistin. Data suggested that the main bioactives in GLPs was F31, which was determined to be a β-heteropolysaccharide with the weight-average molecular weight of 15.9kDa. The possible action mechanism of F31 may be associated with down-regulation of the hepatic glucose regulated enzyme mRNA levels via AMPK activation, improvement of insulin resistance and decrease of epididymal fat/BW ratio. These

  1. ^2H(^18F,p)^19F Study at 6 MeV/u

    Science.gov (United States)

    Kozub, R. L.; Nesaraja, C. D.; Moazen, B. H.; Scott, J. P.; Bardayan, D. W.; Blackmon, J. C.; Gross, C. J.; Shapira, D.; Smith, M. S.; Batchelder, J. C.; Brune, C. R.; Champagne, A. E.; Sahin, L.; Cizewski, J. A.; Thomas, J. S.; Davinson, T.; Woods, P. J.; Greife, U.; Jewett, C.; Livesay, R. J.; Ma, Z.; Parker, P. D.

    2003-04-01

    The degree to which the (p,α) and (p,γ) reactions destroy ^18F at temperatures ˜1-4 x 10^8 K is important for understanding the synthesis of nuclei in nova explosions and for using ^18F as a monitor of nova mechanisms in gamma ray astronomy. The reactions are dominated by low-lying proton resonances near the ^18F+p threshold (E_x=6.411 MeV excitation energy in ^19Ne). To gain further information about these resonances, we have used the inverse ^18F(d,p)^19F neutron transfer reaction at the Holifield Radioactive Ion Beam Facility to selectively populate corresponding mirror states in ^19F. Proton angular distributions were measured for states in ^19F in the excitation energy range 0-9 MeV. Results and implications for the ^18F+p reactions and nuclear structure will be presented. ^1Supported by DOE. ^2ORNL is managed by UT-Battelle, LLC, for the USDOE.

  2. Fluorinated Polyurethane Scaffolds for 19F Magnetic Resonance Imaging

    NARCIS (Netherlands)

    Lammers, Twan; Mertens, Marianne E.; Schuster, Philipp; Rahimi, Khosrow; Shi, Yang; Schulz, Volkmar; Kuehne, Alexander J.C.; Jockenhoevel, Stefan; Kiessling, Fabian

    2017-01-01

    Researchers used fluorinated polyurethane scaffolds for 19F magnetic resonance imaging. They generated a novel fluorinated polymer based on thermoplastic polyurethane (19F -TPU) which possesses distinct properties rendering it suitable for fluorine-based MRI. The 19F -TPU is synthesized from a

  3. Development of 19F-NMR chemical shift detection of DNA B-Z equilibrium using 19F-NMR.

    Science.gov (United States)

    Nakamura, S; Yang, H; Hirata, C; Kersaudy, F; Fujimoto, K

    2017-06-28

    Various DNA conformational changes are in correlation with biological events. In particular, DNA B-Z equilibrium showed a high correlation with translation and transcription. In this study, we developed a DNA probe containing 5-trifluoromethylcytidine or 5-trifluoromethylthymidine to detect DNA B-Z equilibrium using 19 F-NMR. Its probe enabled the quantitative detection of B-, Z-, and ss-DNA based on 19 F-NMR chemical shift change.

  4. Antibiotic of resistence profile of Salmonella spp. serotypes isolated from retail beef in Mexico City.

    Directory of Open Access Journals (Sweden)

    Nova Nayarit-Ballesteros

    2016-05-01

    Full Text Available Objective. To determine the serotype and antibiotic resistance profile of Salmonella spp. isolated from retail ground beef in Mexico City. Materials and methods. A total of 100 samples of ground beef were analyzed. The pathogen was isolated by conventional methods and confirmed by PCR (invA gene, 284 bp. The antibiotic resistance profile was determined by the Kirby-Bauer method while serotyping was performed according to the Kauffman-White scheme. Results. We isolated a total of 19 strains of Lomita (6, Derby (4, Senftenberg (2, Javiana and Cannsttat (1 and undeter- mined (5 serotypes. The strains showed a high resistance rate to ampicillin (18/19, carbenicillin (16/19, tetracyclin (13/19, and trimethoprim-sulfamethoxazole (13/19. Multidrug resistance was observed in 14 isolates. Conclusions. Several Salmonella spp. serotypes of public health significance are circulating in ground beef sold in the major Mexican city. Some of these strains are multi-drug resistance.

  5. Dynamics of Streptococcus pneumoniae serotypes causing acute otitis media isolated from children with spontaneous middle-ear drainage over a 12-year period (1999-2010 in a region of northern Spain.

    Directory of Open Access Journals (Sweden)

    Marta Alonso

    Full Text Available The aim of this study was to determine the serotype and clonal distribution of pneumococci causing acute otitis media (AOM and their relationship with recurrences and mixed infections with other microorganisms under the influence of the 7-valent pneumococcal conjugate vaccine (PCV7. To do this, all pneumococcal isolates collected from the spontaneous middle-ear drainage of children <5 years old diagnosed of AOM by their pediatrician or their general practitioner from 1999 to 2010 were phenotypically characterized and the most frequent serotypes were genotyped. In the 12-year study, 818 episodes of pneumococcal AOM were detected, mostly (70.5% in children younger than 2 years old. In 262 episodes (32%, the pneumococci were isolated with another bacterium, mainly (n=214 Haemophilus influenzae. Mixed infections were similar in children under or over 2 years old. The most frequent serotypes were 19A (n=227, 27.8%, 3 (n=92, 11.2% and 19F (n=74, 9%. Serotypes included in the PCV7 sharply decreased from 62.4% in the pre-vaccination (1999-2001 to 2.2% in the late post-vaccination period (2008-2010. Serotype diversity steadily increased after the introduction of the PCV7 but decreased from 2008-2010 due to the predominant role of serotype 19A isolates, mostly ST276 and ST320. The prevalence of serotype 3 doubled from 6.1% (20/326 in 1999-2004 to 14.6% (72/492 in 2005-2010. Relapses mainly occurred in male infants infected with isolates with diminished antimicrobial susceptibility. Reinfections caused by isolates with the same serotype but different genotype were frequent, highlighting the need for genetic studies to differentiate among similar strains. In conclusion, the main change in pneumococcal AOM observed after the introduction of the PCV7 was the sharp decrease in vaccine serotypes. Also notable was the high burden of serotype 19A in total pneumococcal AOM before and especially after the introduction of the PCV7, as well as in relapses and

  6. Serotype markers in a Streptococcus agalactiae strain collection from Zimbabwe

    Directory of Open Access Journals (Sweden)

    Mavenyengwa R

    2010-01-01

    Full Text Available Objective: Group B streptococci (GBS from Southern African areas have been less well characterized. Our objective was to study serotype and serovariant distribution of carrier GBS strains as part of a study of the epidemiology of GBS carriage in pregnant women from Zimbabwe. Materials and Methods: We studied GBS isolated from 121 healthy pregnant women living in Harare and surrounding areas, Zimbabwe. Capsular polysaccharide (CPS testing for serotype determination and surface-anchored protein testing for serosubtype determination were done by gene-based serotyping (PCR, except for the proteins R3 and a novel protein called Z, which were detected by antibody-based methods. Results: Strains of the CPS types Ia (15.7%, Ib (11.6%, II (8.3%, III (38.8%, V (24.0% and NT (1.7% were detected along with the strain-variable proteins Cί (15.7% of isolates, Cα (19.8%, Alp1 (epsilon-22.3%, Alp3 (5.0%, R4/Rib (46.3%, R3 (27.3%, Z (27.3%, and SAR5 (28.9%, which encodes the R5 protein. Up to four of the protein genes could be possessed or the gene product expressed by one and the same isolate. A total of 32 serovariants were detected. The findings assessed by us as most important were the very low prevalence of the gene Alp3 (Alp3 - 4.9%, high prevalence of R4 (Rib - 46.2%, the proteins R3 (27.3%, Z (27.3%, and of SAR5 (R5 - 28.9%. The low prevalence of Alp3, notably in GBS type V strains, differed from findings with CPS type V GBS from non-African areas. Bacteria of the various CPS types showed distinct CPS/protein-marker associations. Conclusion: The results are of importance in relation to regional variations of GBS phenotypes and genotypes and thus, of importance in planning and research in the context of future vaccine formulations.

  7. Visualizing arthritic inflammation and therapeutic response by fluorine-19 magnetic resonance imaging (19F MRI

    Directory of Open Access Journals (Sweden)

    Balducci Anthony

    2012-06-01

    Full Text Available Abstract Background Non-invasive imaging of inflammation to measure the progression of autoimmune diseases, such as rheumatoid arthritis (RA, and to monitor responses to therapy is critically needed. V-Sense, a perfluorocarbon (PFC contrast agent that preferentially labels inflammatory cells, which are then recruited out of systemic circulation to sites of inflammation, enables detection by 19F MRI. With no 19F background in the host, detection is highly-specific and can act as a proxy biomarker of the degree of inflammation present. Methods Collagen-induced arthritis in rats, a model with many similarities to human RA, was used to study the ability of the PFC contrast agent to reveal the accumulation of inflammation over time using 19F MRI. Disease progression in the rat hind limbs was monitored by caliper measurements and 19F MRI on days 15, 22 and 29, including the height of clinically symptomatic disease. Naïve rats served as controls. The capacity of the PFC contrast agent and 19F MRI to assess the effectiveness of therapy was studied in a cohort of rats administered oral prednisolone on days 14 to 28. Results Quantification of 19F signal measured by MRI in affected limbs was linearly correlated with disease severity. In animals with progressive disease, increases in 19F signal reflected the ongoing recruitment of inflammatory cells to the site, while no increase in 19F signal was observed in animals receiving treatment which resulted in clinical resolution of disease. Conclusion These results indicate that 19F MRI may be used to quantitatively and qualitatively evaluate longitudinal responses to a therapeutic regimen, while additionally revealing the recruitment of monocytic cells involved in the inflammatory process to the anatomical site. This study may support the use of 19F MRI to clinically quantify and monitor the severity of inflammation, and to assess the effectiveness of treatments in RA and other diseases with an inflammatory

  8. In vivo19F MR imaging and spectroscopy for the BNCT optimization

    International Nuclear Information System (INIS)

    Porcari, P.; Capuani, S.; D'Amore, E.; Lecce, M.; La Bella, A.; Fasano, F.; Migneco, L.M.; Campanella, R.; Maraviglia, B.; Pastore, F.S.

    2009-01-01

    The aim of this study was to evaluate in vivo the boron biodistribution and pharmacokinetics of 4-borono-2-fluorophenylalanine ( 19 F-BPA) using 19 F MR Imaging ( 19 F MRI) and Spectroscopy ( 19 F MRS). The correlation between the results obtained by both techniques, 19 F MRI on rat brain and 19 F MRS on blood samples, showed the maximum 19 F-BPA uptake in C6 glioma model at 2.5 h after infusion determining the optimal irradiation time. Moreover, the effect of L-DOPA as potential enhancer of 19 F-BPA tumour intake was assessed using 19 F MRI.

  9. Opsonization of Cryptococcus neoformans by a family of isotype-switch variant antibodies specific for the capsular polysaccharide.

    Science.gov (United States)

    Schlageter, A M; Kozel, T R

    1990-06-01

    A family of immunoglobulin isotype-switch variants was isolated by sib selection from a murine hybridoma which produced an immunoglobulin G subclass 1 (IgG1) antibody specific for the capsular polysaccharide of Cryptococcus neoformans. Antibodies of the IgG1, IgG2a, and IgG2b isotypes had similar serotype specificity patterns in double immunodiffusion assays which used polysaccharides of the four cryptococcal serotypes as antigens. A quantitative difference in the ability of the isotypes to form a precipitate with the polysaccharide was observed in a double immunodiffusion assay and confirmed in a quantitative precipitin assay. The relative precipitating activity of the antibodies was IgG2a greater than IgG1 much greater than IgG2b. Analysis by enzyme-linked immunosorbent assay of the reactivity of the three isotypes with cryptococcal polysaccharide showed identical titers and slopes, suggesting that the variable region of the class-switch antibodies was unaltered. This system allowed us to examine the effect of the Fc portion of the antibody on opsonization of encapsulated cryptococci. Yeast cells were precoated with antibodies of each isotype and incubated with murine macrophages or cultured human monocytes. Antibodies of all three isotypes exhibited a dose-dependent opsonization for phagocytosis by both human and murine phagocytes. The relative opsonic activity of the antibodies was IgG2a greater than IgG1 greater than IgG2b.

  10. Polysaccharides in fungi. XXXII. Hypoglycemic activity and chemical properties of a polysaccharide from the cultural mycelium of Cordyceps sinensis.

    Science.gov (United States)

    Kiho, T; Hui, J; Yamane, A; Ukai, S

    1993-12-01

    Crude polysaccharides were obtained from a hot-water extract and alkaline extracts of the cultural mycelium of Cordyceps sinensis. They showed significant activity in normal mice and streptozotocin-induced diabetic mice as a result of intraperitoneal (i.p.) injection. A crude polysaccharide (CS-OHEP) obtained from 5% sodium hydroxide extract slightly lowered the plasma glucose level in normal mice by oral (p.o.) administration. A neutral polysaccharide (CS-F30) exhibited higher hypoglycemic activity than its crude polysaccharide (CS-OHEP), exhibited by i.p. injection, and it significantly lowered the glucose level by p.o. administration (50 mg/kg). However, it hardly affected the plasma insulin level in normal mice. CS-F30 ([alpha]D + 21 degrees in water) is composed of galactose, glucose and mannose (molar percent, 62:28:10), and its molecular weight is about 45000.

  11. Novel 19F MRS/I nanoprobe based on pH-responsive PEGylated nanogel. pH-dependent 19F magnetic resonance studies

    International Nuclear Information System (INIS)

    Oishi, Motoi; Sumitani, Shogo; Nagasaki, Yukio; Bronich, Tatiana K.; Kabanov, Alexander V.; Boska, Michael D.

    2009-01-01

    The pH-responsive PEGylated nanogels composed of the cross-linked poly[2-(N,N-diethylamino)ethyl methacrylate]-co-poly(2,2,2-trifluoroethyl methacrylate) gel core showed a remarkable on-off regulation of 19 F magnetic resonance signal intensity (T 2 values) as well as signal-to-noise ratios in response to extracellular pH 6.5 of tumor environment under 19 F magnetic resonance spectroscopic imaging (MRS/I), demonstrating the utility of the PEGylated nanogels as solid tumor-specific 19 F MRI/S nanoprobes. (author)

  12. Transport of Streptococcus pneumoniae capsular polysaccharide in MHC Class II tubules.

    Directory of Open Access Journals (Sweden)

    Tom Li Stephen

    2007-03-01

    Full Text Available Bacterial capsular polysaccharides are virulence factors and are considered T cell-independent antigens. However, the capsular polysaccharide Sp1 from Streptococcus pneumoniae serotype 1 has been shown to activate CD4(+ T cells in a major histocompatibility complex (MHC class II-dependent manner. The mechanism of carbohydrate presentation to CD4(+ T cells is unknown. We show in live murine dendritic cells (DCs that Sp1 translocates from lysosomal compartments to the plasma membrane in MHCII-positive tubules. Sp1 cell surface presentation results in reduction of self-peptide presentation without alteration of the MHCII self peptide repertoire. In DM-deficient mice, retrograde transport of Sp1/MHCII complexes resulting in T cell-dependent immune responses to the polysaccharide in vitro and in vivo is significantly reduced. The results demonstrate the capacity of a bacterial capsular polysaccharide antigen to use DC tubules as a vehicle for its transport as an MHCII/saccharide complex to the cell surface for the induction of T cell activation. Furthermore, retrograde transport requires the functional role of DM in self peptide-carbohydrate exchange. These observations open new opportunities for the design of vaccines against microbial encapsulated pathogens.

  13. Distribución de serotipos de Streptococcus pneumoniae aislados de infecciones invasoras en el Hospital de Niños de Santa Fe Serotype distribution of Streptococcus pneumoniae isolated from invasive infections at the Hospital de Niños of Santa Fe.

    Directory of Open Access Journals (Sweden)

    C. Mayoral

    2008-03-01

    Full Text Available Con la introducción de vacunas conjugadas antineumocócicas se observó, en muchos países, disminución de aislamientos de Streptococcus pneumoniae del serotipo 14 y aumento de aislamientos correspondientes a serotipos no incluidos en esas vacunas. En 1993, el Hospital de Niños de Santa Fe comenzó la vigilancia de la distribución de serotipos de Streptococcus pneumoniae invasores. En este trabajo se estudió la correlación entre serotipo y a patología (neumonía/meningitis, b edad (menor o mayor de dos años, y c CIM de penicilina, para los serotipos aislados en el período 2003-2005. El serotipo predominante fue el 14, seguido del 1, 6B, 18C, 7F, 19F y 5. El serotipo 14 mostró asociación estadísticamente significativa con valores de CIM de penicilina entre 0,5 y 2 mg/l, no así con alguna patología, aunque se lo halló con mayor frecuencia en neumonías que en meningitis. Los serotipos 14 y 1 prevalecieron en niños menores y mayores de 2 años, respectivamente. La CIM de penicilina = 2 mg/l se observó más en neumonías que en meningitis. La frecuencia relativa de los diferentes serotipos hallados fue semejante a la observada en el período 1993-99; no obstante, los serotipos 18C, 4, 12F y 22F no se habían encontrado antes. La aparición de nuevos serotipos convierte en importante la vigilancia, dada la necesidad de formular vacunas que los incluyan y que efectivamente prevengan las infecciones neumocócicas más comunes.The serotype distribution of Streptococcus pneumoniae varies through time. The introduction of pneumococcal conjugate vaccines showed a decreased prevalence of pneumococcal invasive isolates belonging to serotype 14 and an increase of serotypes not therein included. In 1993, the Hospital de Niños of Santa Fe began surveillance of the serotype distribution of invasive S. pneumoniae disease. In the period 2003 - 2005, 76 isolates were analysed by studying the correlation between serotype and pathology, age and MIC

  14. [Isolation of Haemophilus influenzae serotypes from deep sites in sick children].

    Science.gov (United States)

    Gatti, B M; Ramirez Gronda, G A; Etchevarría, M; Vescina, C M; Varea, A M; González Ayala, S E

    2004-01-01

    Haemophilus influenzae (Hi) is the causative agent of several human diseases such as sepsis, meningitis, celulitis, and osteoarthritis. We investigated the isolation of Hi serotypes from sterile sites in sick children. One hundred and seventy nine strains from 146 patients were studied, period 1996-2002, at the Microbiology Laboratory, Hospital de Niños Superiora Sor María Ludovica, Argentina. The serotype distribution was:1 a, 112 b,1 c,1 d, 4 e, 3 f y 24 no typable. Since the beginning of universal Hi b vaccination in 1998, we have observed the fast decrease of serotype b and a relative increase of other serotypes.

  15. Automated glycan assembly of a S. pneumoniae serotype 3 CPS antigen

    Directory of Open Access Journals (Sweden)

    Markus W. Weishaupt

    2016-07-01

    Full Text Available Vaccines against S. pneumoniae, one of the most prevalent bacterial infections causing severe disease, rely on isolated capsular polysaccharide (CPS that are conjugated to proteins. Such isolates contain a heterogeneous oligosaccharide mixture of different chain lengths and frame shifts. Access to defined synthetic S. pneumoniae CPS structures is desirable. Known syntheses of S. pneumoniae serotype 3 CPS rely on a time-consuming and low-yielding late-stage oxidation step, or use disaccharide building blocks which limits variability. Herein, we report the first iterative automated glycan assembly (AGA of a conjugation-ready S. pneumoniae serotype 3 CPS trisaccharide. This oligosaccharide was assembled using a novel glucuronic acid building block to circumvent the need for a late-stage oxidation. The introduction of a washing step with the activator prior to each glycosylation cycle greatly increased the yields by neutralizing any residual base from deprotection steps in the synthetic cycle. This process improvement is applicable to AGA of many other oligosaccharides.

  16. NbF{sub 5} and TaF{sub 5}: Assignment of {sup 19}F NMR resonances and chemical bond analysis from GIPAW calculations

    Energy Technology Data Exchange (ETDEWEB)

    Biswal, Mamata, E-mail: Mamata.Biswal-Susanta_Kumar_Nayak.Etu@univ-lemans.fr [LUNAM Université, Université du Maine, CNRS UMR 6283, Institut des Molécules et des Matériaux du Mans, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France); Body, Monique, E-mail: monique.body@univ-lemans.fr [LUNAM Université, Université du Maine, CNRS UMR 6283, Institut des Molécules et des Matériaux du Mans, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France); Legein, Christophe, E-mail: christophe.legein@univ-lemans.fr [LUNAM Université, Université du Maine, CNRS UMR 6283, Institut des Molécules et des Matériaux du Mans, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France); Sadoc, Aymeric, E-mail: Aymeric.Sadoc@cnrs-imn.fr [Institut des Matériaux Jean Rouxel (IMN), Université de Nantes, CNRS, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France); Boucher, Florent, E-mail: Florent.Boucher@cnrs-imn.fr [Institut des Matériaux Jean Rouxel (IMN), Université de Nantes, CNRS, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France)

    2013-11-15

    The {sup 19}F isotropic chemical shifts (δ{sub iso}) of two isomorphic compounds, NbF{sub 5} and TaF{sub 5}, which involve six nonequivalent fluorine sites, have been experimentally determined from the reconstruction of 1D {sup 19}F MAS NMR spectra. In parallel, the corresponding {sup 19}F chemical shielding tensors have been calculated using the GIPAW method for both experimental and DFT-optimized structures. Furthermore, the [M{sub 4}F{sub 20}] units of NbF{sub 5} and TaF{sub 5} being held together by van der Waals interactions, the relevance of Grimme corrections to the DFT optimization processes has been evaluated. However, the semi-empirical dispersion correction term introduced by such a method does not show any significant improvement. Nonetheless, a complete and convincing assignment of the {sup 19}F NMR lines of NbF{sub 5} and TaF{sub 5} is obtained, ensured by the linearity between experimental {sup 19}F δ{sub iso} values and calculated {sup 19}F isotropic chemical shielding σ{sub iso} values. The effects of the geometry optimizations have been carefully analyzed, confirming among other matters, the inaccuracy of the experimental structure of NbF{sub 5}. The relationships between the fluorine chemical shifts, the nature of the fluorine atoms (bridging or terminal), the position of the terminal ones (opposite or perpendicular to the bridging ones), the fluorine charges, the ionicity and the length of the M–F bonds have been established. Additionally, for three of the {sup 19}F NMR lines of NbF{sub 5}, distorted multiplets, arising from {sup 1}J-coupling and residual dipolar coupling between the {sup 19}F and {sup 93}Nb nuclei, were simulated yielding to values of {sup 93}Nb–{sup 19}F {sup 1}J-coupling for the corresponding fluorine sites. - Graphical abstract: The complete assignment of the {sup 19}F NMR lines of NbF{sub 5} and TaF{sub 5} allow establishing relationships between the {sup 19}F δ{sub iso} values, the nature of the fluorine atoms

  17. Ring current shifts in {sup 19}F-NMR of membrane proteins

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dongsheng, E-mail: liudsh@shanghaitech.edu.cn; Wüthrich, Kurt, E-mail: kwuthrich@shanghaitech.edu.cn [ShanghaiTech University, iHuman Institute (China)

    2016-05-15

    Fluorine-19 NMR markers are attractive reporter groups for use in studies of complex biomacromolecular systems, in particular also for studies of function-related conformational equilibria and rate processes in membrane proteins. Advantages of {sup 19}F-NMR probes include high sensitivity of the {sup 19}F chemical shifts to variations in the non-covalent environment. Nonetheless, in studies of G protein-coupled receptors (GPCR) we encountered situations where {sup 19}F chemical shifts were not responsive to conformational changes that had been implicated by other methods. This prompted us to examine possible effects of aromatic ring current fields on the chemical shifts of {sup 19}F-NMR probes used in GPCRs. Analysis of previously reported {sup 19}F-NMR data on the β{sub 2}-adrenergic receptor and mammalian rhodopsin showed that all {sup 19}F-labeling sites which manifested conformational changes are located near aromatic residues. Although ring current effects are small when compared to other known non-covalent effects on {sup 19}F chemical shifts, there is thus an indication that their contributions are significant when studying activation processes in GPCRs, since the observed activation-related {sup 19}F-NMR chemical shifts are comparable in size to the calculated ring current shifts. Considering the impact of ring current shifts may thus be helpful in identifying promising indigenous or engineered labeling sites for future {sup 19}F-NMR studies of GPCR activation, and novel information may be obtained on the nature of conformational rearrangements near the {sup 19}F-labels. It will then also be interesting to see if the presently indicated role of ring current shifts in membrane protein studies with {sup 19}F-NMR markers can be substantiated by a more extensive data base resulting from future studies.

  18. Structural studies of some bacterial capsular polysaccharides from the family enterobacteriaceae: Klebsiella serotypes K79 and K35 and Escherichia coli serotype K44

    Energy Technology Data Exchange (ETDEWEB)

    Lim, A.V.S.

    1986-01-01

    The techniques of sugar analysis, methylation, chromic acid oxidation, deamination, base-catalyzed uronic acid degradation, Smith degradation and partial hydrolysis were used in the structural elucidation of bacterial capsular polysaccharides. Methods such as gas-liquid chromatography, gas chromatography-mass spectrometry, gel permeation, ion-exchange and paper-chromatography were used to isolate and characterize oligosaccharides obtained from degradative procedures. N.m.r. spectroscopy (/sup 1/H and /sup 13/C) was widely used in the characterization of the polysaccharides and of derived poly- and oligo-saccharides. In a few instances, n.m.r. spectroscopy and mass spectrometry were used to delineate the sequence of the sugars in the structure of the poly- and oligo-saccharides. The bacteriophage-induced depolymerizations of the capsular polysaccharides of Klebsiella K79 and E. coli K44 are also reported in this thesis. The sum of these experiments demonstrated that the endoglycanase associated with Klebsiella Phi 79 had ..beta..-galactosidase activity. The endoglycanase from E. coli Phi 44 exhibited ..beta..-N-acetyl-galactosaminidase activity which is novel, in that it is the first reported action of this nature in the bacteriophages isolated for the species E. coli.

  19. Optimal serotype compositions for Pneumococcal conjugate vaccination under serotype replacement.

    Science.gov (United States)

    Nurhonen, Markku; Auranen, Kari

    2014-02-01

    Pneumococcal conjugate vaccination has proved highly effective in eliminating vaccine-type pneumococcal carriage and disease. However, the potential adverse effects of serotype replacement remain a major concern when implementing routine childhood pneumococcal conjugate vaccination programmes. Applying a concise predictive model, we present a ready-to-use quantitative tool to investigate the implications of serotype replacement on the net effectiveness of vaccination against invasive pneumococcal disease (IPD) and to guide in the selection of optimal vaccine serotype compositions. We utilise pre-vaccination data on pneumococcal carriage and IPD and assume partial or complete elimination of vaccine-type carriage, its replacement by non-vaccine-type carriage, and stable case-to-carrier ratios (probability of IPD per carriage episode). The model predicts that the post-vaccination IPD incidences in Finland for currently available vaccine serotype compositions can eventually decrease among the target age group of children replacement through herd effects, the decrease among the older population is predicted to be much less (20-40%). We introduce a sequential algorithm for the search of optimal serotype compositions and assess the robustness of inferences to uncertainties in data and assumptions about carriage and IPD. The optimal serotype composition depends on the age group of interest and some serotypes may be highly beneficial vaccine types in one age category (e.g. 6B in children), while being disadvantageous in another. The net effectiveness will be improved only if the added serotype has a higher case-to-carrier ratio than the average case-to-carrier ratio of the current non-vaccine types and the degree of improvement in effectiveness depends on the carriage incidence of the serotype. The serotype compositions of currently available pneumococcal vaccines are not optimal and the effectiveness of vaccination in the population at large could be improved by including

  20. Emerging, Non-PCV13 Serotypes 11A and 35B of Streptococcus pneumoniae Show High Potential for Biofilm Formation In Vitro.

    Directory of Open Access Journals (Sweden)

    Mirian Domenech

    Full Text Available Since the use of pneumococcal conjugate vaccines PCV7 and PCV13 in children became widespread, invasive pneumococcal disease (IPD has dramatically decreased. Nevertheless, there has been a rise in incidence of Streptococcus pneumoniae non-vaccine serotypes (NVT colonising the human nasopharynx. Nasopharyngeal colonisation, an essential step in the development of S. pneumoniae-induced IPD, is associated with biofilm formation. Although the capsule is the main pneumococcal virulence factor, the formation of pneumococcal biofilms might, in fact, be limited by the presence of capsular polysaccharide (CPS.We used clinical isolates of 16 emerging, non-PCV13 serotypes as well as isogenic transformants of the same serotypes. The biofilm formation capacity of isogenic transformants expressing CPSs from NVT was evaluated in vitro to ascertain whether this trait can be used to predict the emergence of NVT. Fourteen out of 16 NVT analysed were not good biofilm formers, presumably because of the presence of CPS. In contrast, serotypes 11A and 35B formed ≥45% of the biofilm produced by the non-encapsulated M11 strain.This study suggest that emerging, NVT serotypes 11A and 35B deserve a close surveillance.

  1. Collective effects in {sup 17}F and {sup 19}Ne; Effets collectifs dans {sup 17}F et {sup 19}Ne

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, P; Leveque, A; Grjebine, T; Barloutaud, R [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    The quadrupolar transition periods {sup 17}F1/2+ {yields} 5/2+ and {sup 19}Ne5/2+ {yields} 1/2+ have been measured, and are compatible with the model of a weak coupling between core and external nucleons. (author) [French] Les periodes des transitions quadrupolaires {sup 17}F1/2+ {yields} 5/2+ et {sup 19}Ne5/2+ {yields} 1/2+ ont ete mesurees et sont compatibles avec le modele d'un couplage faible entre coeur et nucleons exterieures. (auteur)

  2. Preparation, characterization and antioxidant activity of polysaccharide from spent Lentinus edodes substrate.

    Science.gov (United States)

    Zhu, Hongji; Tian, Li; Zhang, Lei; Bi, Jingxiu; Song, Qianqian; Yang, Hui; Qiao, Jianjun

    2018-06-01

    This study explored the potential of spent Lentinus edodes substrate, a by-product of mushroom industries causing environmental pollution, serving as materials to produce antioxidant polysaccharide. The extraction process of spent Lentinus edodes substrate polysaccharide (SLSP) was optimized and the effects of drying methods on chemical composition, morphological property and antioxidant activity were investigated. Results showed that freeze-dried SLSP (SLSP-F) exhibited the best quality in terms of the polysaccharide yield (13.00%) and antioxidant activity. The EC 50 values of SLSP-F on DPPH, ABTS and superoxide anion radicals was 0.051mg/mL, 0.379mg/mL, 0.719mg/mL, respectively, which was significantly lower than that of freeze-dried Lentinus edodes polysaccharide (LP-F). After purification by Sephadex G-150, the purified SLSP-F (PSP) has a molecular weight of 16.77kDa. Compared with LP-F, PSP has more reducing sugars and uronic acids in chemical composition and higher contents of xylose, glucose and galactose in monosaccharide composition. FT-IR and NMR spectroscopy analysis revealed that PSP has both α and β glycosidic bonds and massive acetyl groups, which is different from LP-F mainly composed of 1, 3 linked α-D-Manp residue with some acetyl groups. The findings provided a reliable approach for the development of antioxidant polysaccharide from spent Lentinus edodes substrate. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Carriage and serotype distribution of Streptococcus agalactiae in third trimester pregnancy in southern Ghana

    DEFF Research Database (Denmark)

    Slotved, Hans-Christian; Dayie, Nicholas T K D; Banini, Josephine A N

    2017-01-01

    was performed on a single subcultured colony. Gram staining was performed, and isolates were evaluated for beta-haemolytic reactions. Furthermore, the isolates were serotyped using the GBS latex serotyping kit. RESULTS: The carriage rates were found to be 25.5% (95% CI: 19.6-32.1) to 28.0% (95% CI: 21...... of this study revealed that prevalence of GBS colonization in pregnant women in Greater Accra region is high and comparable to rates observed in South Africa and Western countries. The most prevalent serotypes were serotypes VII and IX, which have not been observed before in West Africa....

  4. Isolation, characterization and investigation of Plantago ovata husk polysaccharide as superdisintegrant.

    Science.gov (United States)

    Pawar, Harshal; Varkhade, Chhaya

    2014-08-01

    Psyllium husk (Plantago ovata, Family: Plantaginaceae) contains a high proportion of hemicellulose, composed of a xylan backbone linked with arabinose, rhamnose, and galacturonic acid units (arabinoxylans). Polysaccharide was isolated from Psyllium husk using solvent precipitation method. The isolated polysaccharide was evaluated for various physicochemical parameters. The rheological behavior of polysaccharide (1% w/v in water) was studied using Brookfield viscometer. Polysaccharide derived from the husk of P. ovata was investigated as superdisintegrant in the fast dissolving tablets. Valsartan, an antihypertensive drug, was selected as a model drug. The tablets of Valsartan were prepared separately using different concentrations (1, 2.5, 5, 7.5% w/w) of isolated Plantago ovata (P. ovata) husk polysaccharide (Natural) and crospovidone as a synthetic superdisintegrant by direct compression method. The prepared tablets were evaluated for various pre-compression and post-compression parameters. The drug excipient interactions were characterized by FTIR studies. The formulation F4 containing7.5% polysaccharide showed rapid wetting time and disintegration time as compared to formulation prepared using synthetic superdisintegrant at the same concentration level. Hence batch F4 was considered as optimized formulation. The stability studies were performed on formulation F4. The disintegration time and in vitro drug release of the optimized formulation was compared with the marketed formulation (Conventional tablets). Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Molecular serotyping, virulence gene profiling and pathogenicity of Streptococcus agalactiae isolated from tilapia farms in Thailand by multiplex PCR.

    Science.gov (United States)

    Kannika, K; Pisuttharachai, D; Srisapoome, P; Wongtavatchai, J; Kondo, H; Hirono, I; Unajak, S; Areechon, N

    2017-06-01

    This study aimed to biotype Streptococcus agalactiae isolated from tilapia farms in Thailand based on molecular biotyping methods and to determine the correlation between the serotype and virulence of bacteria. In addition to a biotyping (serotyping) technique based on multiplex PCR of cps genes, in this study, we developed multiplex PCR typing of Group B streptococcus (GBS) virulence genes to examine three clusters of virulence genes and their correlation with the pathogenicity of S. agalactiae. The epidemiology of S. agalactiae in Thailand was analysed to provide bacterial genetic information towards a future rational vaccine strategy for tilapia culture systems. Streptococcus agalactiae were isolated from diseased tilapia from different areas of Thailand. A total of 124 S. agalactiae isolates were identified by phenotypic analysis and confirmed by 16S rRNA PCR. Bacterial genotyping was conducted based on (i) molecular serotyping of the capsular polysaccharide (cps) gene cluster and (ii) virulence gene profiling using multiplex PCR analysis of 14 virulence genes (lmb, scpB, pavA, cspA, spb1, cyl, bca, rib, fbsA, fbsB, cfb, hylB, bac and pbp1A/ponA). Only serotypes Ia and III were found in this study; serotype Ia lacks the lmb, scpB and spb1 genes, whereas serotype III lacks only the bac gene. Virulence tests in juvenile Nile tilapia demonstrated a correlation between the pathogenicity of the bacteria and their virulence gene profile, with serotype III showing higher virulence than serotype Ia. Epidemiological analysis showed an almost equal distribution in all regions of Thailand, except serotype III was found predominantly in the southern areas. Only two serotypes of S. agalactiae were isolated from diseased tilapia in Thailand. Serotype Ia showed fewer virulence genes and lower virulence than serotype III. Both serotypes showed a similar distribution throughout Thailand. We identified two major serotypes of S. agalactiae isolates associated with the outbreak in

  6. Towards the development of a DNA-sequence based approach to serotyping of Salmonella enterica

    Directory of Open Access Journals (Sweden)

    Logan Julie MJ

    2004-08-01

    Full Text Available Abstract Background The fliC and fljB genes in Salmonella code for the phase 1 (H1 and phase 2 (H2 flagellin respectively, the rfb cluster encodes the majority of enzymes for polysaccharide (O antigen biosynthesis, together they determine the antigenic profile by which Salmonella are identified. Sequencing and characterisation of fliC was performed in the development of a molecular serotyping technique. Results FliC sequencing of 106 strains revealed two groups; the g-complex included those exhibiting "g" or "m,t" antigenic factors, and the non-g strains which formed a second more diverse group. Variation in fliC was characterised and sero-specific motifs identified. Furthermore, it was possible to identify differences in certain H antigens that are not detected by traditional serotyping. A rapid short sequencing assay was developed to target serotype-specific sequence motifs in fliC. The assay was evaluated for identification of H1 antigens with a panel of 55 strains. Conclusion FliC sequences were obtained for more than 100 strains comprising 29 different H1 alleles. Unique pyrosequencing profiles corresponding to the H1 component of the serotype were generated reproducibly for the 23 alleles represented in the evaluation panel. Short read sequence assays can now be used to identify fliC alleles in approximately 97% of the 50 medically most important Salmonella in England and Wales. Capability for high throughput testing and automation give these assays considerable advantages over traditional methods.

  7. Characterization and biological role of the O-polysaccharide gene cluster of Yersinia enterocolitica serotype O : 9

    DEFF Research Database (Denmark)

    Skurnik, Mikael; Biedzka-Sarek, Marta; Lubeck, Peter S.

    2007-01-01

    Yersinia enterocolitica serotype O:9 is a gram-negative enteropathogen that infects animals and humans. The role of lipopolysaccharide (LPS) in Y. enterocolitica O:9 pathogenesis, however, remains unclear. The O:9 LPS consists of lipid A to which is linked the inner core oligosaccharide, serving...

  8. 2-Fluoro-L-Fucose Is a Metabolically Incorporated Inhibitor of Plant Cell Wall Polysaccharide Fucosylation

    Science.gov (United States)

    Wallace, Ian S.

    2015-01-01

    The monosaccharide L-fucose (L-Fuc) is a common component of plant cell wall polysaccharides and other plant glycans, including the hemicellulose xyloglucan, pectic rhamnogalacturonan-I (RG-I) and rhamnogalacturonan-II (RG-II), arabinogalactan proteins, and N-linked glycans. Mutations compromising the biosynthesis of many plant cell wall polysaccharides are lethal, and as a result, small molecule inhibitors of plant cell wall polysaccharide biosynthesis have been developed because these molecules can be applied at defined concentrations and developmental stages. In this study, we characterize novel small molecule inhibitors of plant fucosylation. 2-fluoro-L-fucose (2F-Fuc) analogs caused severe growth phenotypes when applied to Arabidopsis seedlings, including reduced root growth and altered root morphology. These phenotypic defects were dependent upon the L-Fuc salvage pathway enzyme L-Fucose Kinase/ GDP-L-Fucose Pyrophosphorylase (FKGP), suggesting that 2F-Fuc is metabolically converted to the sugar nucleotide GDP-2F-Fuc, which serves as the active inhibitory molecule. The L-Fuc content of cell wall matrix polysaccharides was reduced in plants treated with 2F-Fuc, suggesting that this molecule inhibits the incorporation of L-Fuc into these polysaccharides. Additionally, phenotypic defects induced by 2F-Fuc treatment could be partially relieved by the exogenous application of boric acid, suggesting that 2F-Fuc inhibits RG-II biosynthesis. Overall, the results presented here suggest that 2F-Fuc is a metabolically incorporated inhibitor of plant cellular fucosylation events, and potentially suggest that other 2-fluorinated monosaccharides could serve as useful chemical probes for the inhibition of cell wall polysaccharide biosynthesis. PMID:26414071

  9. Surface antigens contribute differently to the pathophysiological features in serotype K1 and K2 Klebsiella pneumoniae strains isolated from liver abscesses.

    Science.gov (United States)

    Yeh, Kuo-Ming; Chiu, Sheng-Kung; Lin, Chii-Lan; Huang, Li-Yueh; Tsai, Yu-Kuo; Chang, Jen-Chang; Lin, Jung-Chung; Chang, Feng-Yee; Siu, Leung-Kei

    2016-01-01

    The virulence role of surface antigens in a single serotype of Klebsiella pneumoniae strain have been studied, but little is known about whether their contribution will vary with serotype. To investigate the role of K and O antigen in hyper-virulent strains, we constructed O and K antigen deficient mutants from serotype K1 STL43 and K2 TSGH strains from patients with liver abscess, and characterized their virulence in according to the abscess formation and resistance to neutrophil phagocytosis, serum, and bacterial clearance in liver. Both of K1 and K2-antigen mutants lost their wildtype resistance to neutrophil phagocytosis and hepatic clearance, and failed to cause abscess formation. K2-antigen mutant became serum susceptible while K1-antigen mutant maintained its resistance to serum killing. The amount of glucuronic acid, indicating the amount of capsular polysaccharide (CPS, K antigen), was inversed proportional to the rate of phagocytosis. O-antigen mutant of serotype K1 strains had significantly more amount of CPS, and more resistant to neutrophil phagocytosis than its wildtype counterpart. O-antigen mutants of serotype K1 and K2 strains lost their wildtype serum resistance, and kept resistant to neutrophil phagocytosis. While both mutants lacked the same O1 antigen, O-antigen mutant of serotype K1 became susceptible to liver clearance and cause mild abscess formation, but its serotype K2 counterpart maintained these wildtype virulence. We conclude that the contribution of surface antigens to virulence of K. pneumoniae strains varies with serotypes.

  10. A monoclonal antibody based capture ELISA for botulinum neurotoxin serotype B: toxin detection in food

    Science.gov (United States)

    Botulism is a serious foodborne neuroparalyic disease caused by botulinum neurotoxin (BoNT) produced by the anaerobic bacterium Clostridium botulinum. Seven toxin serotypes (A-H) have been described. The majority of human cases of botulism are caused by serotypes A and B followed by E and F. We repo...

  11. Serotype Distribution and Antimicrobial Sensitivity Profile of Streptococcus pneumoniae Carried in Healthy Toddlers before PCV13 Introduction in Niamey, Niger.

    Directory of Open Access Journals (Sweden)

    Sani Ousmane

    Full Text Available To mitigate the burden of pneumococcal infections in Niger, a 13-valent pneumococcal vaccine, PCV13, was introduced for routine child vaccination in July 2014. In order to provide pre-vaccine baseline data and allow appreciation of changes on carriage due to vaccination, we analyzed retrospectively pneumococcal isolates obtained from healthy, 0 to 2 year old children prior to the vaccine introduction.From June 5, 2007, to May 26, 2008, 1200 nasopharyngeal swabs were collected from healthy 0 to 2 year old children and analyzed by standard microbiological methods. Serotyping was done by SM-PCR and the data were analyzed with R version 2.15.0 (2012-03-30.Streptococcus pneumoniae was detected in 654/1200 children (54.5% among whom 339 (51.8% were males. The ages of the study subjects varied from few days to 26 months (mean = 7.1, median = 6, 95% CI [6.8-7.4]. Out of 654 frozen isolates, 377 (54.8% were able to be re-grown and analyzed. In total, 32 different serogroups/serotypes were detected of which, the most prevalent were 6/(6A/6B/6C/6D (15.6%, 23F (10.6%, 19F (9.3%, 14 (9%, 19A (5.6%, 23B (4.0%, 25F/38 (3.7%, 18/(18A/18B/18C/18F (2.9% and PCR non-typeable (16.4%. Eleven serogroups/serotypes accounting for 57.3% (216/377 were of PCV13 types. Of the 211/377 (56% isolates tested for drug sensitivity, 23/211 (10.9%, 24/211 (11.4%, 9/211(4.3% and 148/210 (70.5% were respectively resistance to oxacillin, chloramphenicol, erythromycin and tetracycline. Thirteen of the oxacillin resistant isolates were additionally multidrug-resistant. No resistance was however detected to gentamycin500μg and to fluoroquinolones (ø Norfloxacin5μg 3 months and presence in family of more than one sibling aged 3 months and presence in family of children aged < 6 years were significant factors for pneumococcal carriage. The present data should help understanding post vaccine introduction changes in pneumococcal carriage and infections for better action.

  12. Genotyping and serotyping of macrolide and multidrug resistant Streptococcus pneumoniae isolated from carrier children

    Directory of Open Access Journals (Sweden)

    S F Swedan

    2016-01-01

    Full Text Available Aims: Streptococcus pneumoniae, an opportunistic pathogen commonly carried asymptomatically in the nasopharynx of children, is associated with increasing rates of treatment failures due to a worldwide increase in drug resistance. We investigated the carriage of S. pneumoniae in children 5 years or younger, the identity of prevalent serotypes, the rates of resistance to macrolides and other antimicrobial agents and the genotypes responsible for macrolide resistance. Materials and Methods: Nasopharyngeal swabs were collected from 157 children under 5 years for cultural isolation of S. pneumoniae. Antibiogram of isolates  was determined using the disk diffusion test, and the minimal inhibitory concentration to macrolides was determined using the E-test. Isolate serotypes and macrolide resistance genes, erm(B and mef(E, were identified using multiplex polymerase chain reactions. Results: S. pneumoniae was recovered from 33.8% of children; 41.9% among males and 21.9% among females (P = 0.009. The highest carriage rate occurred among age groups 7-12 months and 49-60 months. Most frequent serotypes were 19F, 6A/B, 11A, 19A, 14 and 15B/C.  Resistance to macrolides was 60.4%. Resistance to oxacillin, trimethoprim/sulfamethoxazole and clindamycin was present among 90.6%, 54.7% and 32.1% of isolates, respectively. All isolates were susceptible to chloramphenicol, levofloxacin and vancomycin. Isolates resistant to one or more macrolide drugs were more likely to be multidrug resistant. Resistance to clindamycin or oxacillin coexisted with macrolide resistance. Among the erythromycin-resistant isolates, erm(B, mef(E and erm(B and mef(E genes were present at rates of 43.8%, 37.5% and 6.3%, respectively. Erm(B and mef(E were associated with very high level and moderate-to-high level resistance to macrolides, respectively. Conclusion: A significant proportion of children harboured macrolide and multidrug-resistant S. pneumoniae.

  13. 2-Fluoro-L-Fucose Is a Metabolically Incorporated Inhibitor of Plant Cell Wall Polysaccharide Fucosylation.

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    Jose A Villalobos

    Full Text Available The monosaccharide L-fucose (L-Fuc is a common component of plant cell wall polysaccharides and other plant glycans, including the hemicellulose xyloglucan, pectic rhamnogalacturonan-I (RG-I and rhamnogalacturonan-II (RG-II, arabinogalactan proteins, and N-linked glycans. Mutations compromising the biosynthesis of many plant cell wall polysaccharides are lethal, and as a result, small molecule inhibitors of plant cell wall polysaccharide biosynthesis have been developed because these molecules can be applied at defined concentrations and developmental stages. In this study, we characterize novel small molecule inhibitors of plant fucosylation. 2-fluoro-L-fucose (2F-Fuc analogs caused severe growth phenotypes when applied to Arabidopsis seedlings, including reduced root growth and altered root morphology. These phenotypic defects were dependent upon the L-Fuc salvage pathway enzyme L-Fucose Kinase/ GDP-L-Fucose Pyrophosphorylase (FKGP, suggesting that 2F-Fuc is metabolically converted to the sugar nucleotide GDP-2F-Fuc, which serves as the active inhibitory molecule. The L-Fuc content of cell wall matrix polysaccharides was reduced in plants treated with 2F-Fuc, suggesting that this molecule inhibits the incorporation of L-Fuc into these polysaccharides. Additionally, phenotypic defects induced by 2F-Fuc treatment could be partially relieved by the exogenous application of boric acid, suggesting that 2F-Fuc inhibits RG-II biosynthesis. Overall, the results presented here suggest that 2F-Fuc is a metabolically incorporated inhibitor of plant cellular fucosylation events, and potentially suggest that other 2-fluorinated monosaccharides could serve as useful chemical probes for the inhibition of cell wall polysaccharide biosynthesis.

  14. Structural Studies of Bcl-xL/ligand Complexes using {sup 19}F NMR

    Energy Technology Data Exchange (ETDEWEB)

    Yu Liping; Hajduk, Philip J.; Mack, Jamey; Olejniczak, Edward T. [GPRD, Abbott Laboratories, Pharmaceutical Discovery Division (United States)], E-mail: Edward.olejniczak@abbott.com

    2006-04-15

    Fluorine atoms are often incorporated into drug molecules as part of the lead optimization process in order to improve affinity or modify undesirable metabolic and pharmacokinetic profiles. From an NMR perspective, the abundance of fluorinated drug leads provides an exploitable niche for structural studies using {sup 19}F NMR in the drug discovery process. As {sup 19}F has no interfering background signal from biological sources, {sup 19}F NMR studies of fluorinated drugs bound to their protein receptors can yield easily interpretable and unambiguous structural constraints. {sup 19}F can also be selectively incorporated into proteins to obtain additional constraints for structural studies. Despite these advantages, {sup 19}F NMR has rarely been exploited for structural studies due to its broad lines in macromolecules and their ligand complexes, leading to weak signals in {sup 1}H/{sup 19}F heteronuclear NOE experiments. Here we demonstrate several different experimental strategies that use {sup 19}F NMR to obtain ligand-protein structural constraints for ligands bound to the anti-apoptotic protein Bcl-xL, a drug target for anti-cancer therapy. These examples indicate the applicability of these methods to typical structural problems encountered in the drug development process.

  15. Fred Neufeld and pneumococcal serotypes: foundations for the discovery of the transforming principle.

    Science.gov (United States)

    Eichmann, Klaus; Krause, Richard M

    2013-07-01

    During the first decade of the twentieth century, the German bacteriologist Fred Neufeld, later Director of the Robert Koch-Institute in Berlin, first described the differentiation of pneumococci into serotypes on the basis of type-specific antisera. This finding was essential for subsequent research at the Rockefeller Institute of Medical Research (RIMR) in New York, and elsewhere, aiming for the conquest of human pneumococcal pneumonia, including antiserum therapy, the discovery that the type-specific antigens were carbohydrates, and the development of effective multivalent pneumococcal polysaccharide vaccines. Moreover, on the basis of pneumococcal serotypes Fred Griffith, in 1928 in London, discovered pneumococcal transformation, and Oswald T. Avery and coworkers, in 1944 at RIMR, identified DNA as the transforming substance. This sequence of events, leading to today's knowledge that genes consist of DNA, was initiated by a farsighted move of Simon Flexner, first Director of the RIMR, who asked Neufeld to send his pneumococcal typing strains, thus setting the stage for pneumococcal research at RIMR. Here, we describe Fred Neufeld's contributions in this development, which have remained largely unknown.

  16. Serotyping of Actinobacillus pleuropneumoniae serotype 5 strains using a monoclonal-based polystyrene agglutination test

    DEFF Research Database (Denmark)

    Dubreuil, J.D.; Letellier, A.; Stenbæk, Eva

    1996-01-01

    A polystyrene agglutination test has been developed for serotyping Actinobacillus pleuropneumoniae serotype 5a and 5b strains. Protein A-coated polystyrene microparticles were sensitized with a murine monoclonal antibody recognizing an epitope on serotype 5 LPS-O chain as shown by SDS-PAGE and We......A polystyrene agglutination test has been developed for serotyping Actinobacillus pleuropneumoniae serotype 5a and 5b strains. Protein A-coated polystyrene microparticles were sensitized with a murine monoclonal antibody recognizing an epitope on serotype 5 LPS-O chain as shown by SDS...... suspension of bacterial cells grown for 18 h. All A, pleuropneumoniae strains had been previously serotyped using standard procedures, The polystyrene agglutination test was rapid (less than 3 min) and easy to perform. Overall a very good correlation (97.3%) with the standard techniques was found...

  17. Double-tuned radiofrequency coil for (19)F and (1)H imaging.

    Science.gov (United States)

    Otake, Yosuke; Soutome, Yoshihisa; Hirata, Koji; Ochi, Hisaaki; Bito, Yoshitaka

    2014-01-01

    We developed a double-tuned radiofrequency (RF) coil using a novel circuit method to double tune for fluorine-19 (19F) and 1H magnetic resonance imaging, whose frequencies are very close to each other. The RF coil consists of 3 parallel-connected series inductor capacitor circuits. A computer simulation for our double-tuned RF coil with a phantom demonstrated that the coil has tuned resonant frequency and high sensitivity for both 19F and 1H. Drug distribution was visualized at 7 tesla using this RF coil and a rat administered perfluoro 15-crown-5-ether emulsion. The double-tune RF coil we developed may be a powerful tool for 19F and 1H imaging.

  18. Evaluation of cross-protection of bluetongue virus serotype 4 with other serotypes in sheep

    Directory of Open Access Journals (Sweden)

    Gcwalisile B. Zulu

    2014-10-01

    Full Text Available Bluetongue (BT is a non-contagious disease of sheep and other domestic and wild ruminants caused by the bluetongue virus (BTV. Currently 26 serotypes of the virus have been identified. In South Africa, 22 serotypes have been identified and BT is controlled mainly by annual vaccinations using a freeze-dried live attenuated polyvalent BTV vaccine. The vaccine is constituted of 15 BTV serotypes divided into three separate bottles and the aim is to develop a vaccine using fewer serotypes without compromising the immunity against the disease. This study is based on previously reported cross-neutralisation of specific BTV serotypes in in vitro studies. Bluetongue virus serotype 4 was selected for this trial and was tested for cross-protection against serotype 4 (control, 1 (unrelated serotype, 9, 10 and 11 in sheep using the serum neutralisation test. The purpose of the study was to determine possible cross-protection of different serotypes in sheep. Of those vaccinated with BTV-4 and challenged with BTV-1, which is not directly related to BTV-4, 20% were completely protected and 80% showed clinical signs, but the reaction was not as severe as amongst the unvaccinated animals. In the group challenged with BTV-10, some showed good protection and some became very sick. Those challenged with BTV-9 and BTV-11 had good protection. The results showed that BTV-4 does not only elicit a specific immune response but can also protect against other serotypes.

  19. Measurement of the fluorine content of three NBS standard reference materials by use of the /sup 19/F(p, p'. gamma. )/sup 19/F reaction

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, A L; Kraner, H W; Shroy, R E; Jones, K W [Brookhaven National Lab., Upton, NY (USA)

    1984-08-01

    The fluorine contents of National Bureau of Standards (NBS) Standard Reference Materials (SRM) 91, opal glass; 120b, phosphate rock; and 2671a, freeze-dried urine; have been measured using the /sup 19/F(p,p'..gamma..)/sup 19/F reaction at a proton energy of 3.1 MeV. The results are in good agreement with the values certified by the NBS.

  20. Streptococcus iniae cpsG alters capsular carbohydrate composition and is a cause of serotype switching in vaccinated fish.

    Science.gov (United States)

    Heath, Candice; Gillen, Christine M; Chrysanthopoulos, Panagiotis; Walker, Mark J; Barnes, Andrew C

    2016-09-25

    Streptococcus iniae causes septicaemia and meningitis in marine and freshwater fish wherever they are farmed in warm-temperate and tropical regions. Although serotype specific, vaccination with bacterins (killed bacterial cultures) is largely successful and vaccine failure occurs only occasionally through emergence of new capsular serotypes. Previously we showed that mutations in vaccine escapes are restricted to a limited repertoire of genes within the 20-gene capsular polysaccharide (cps) operon. cpsG, a putative UDP-galactose 4-epimerase, has three sequence types based on the insertion or deletion of the three amino acids leucine, serine and lysine in the substrate binding site of the protein. To elucidate the role of cpsG in capsular polysaccharide (CPS) biosynthesis and capsular composition, we first prepared isogenic knockout and complemented mutants of cpsG by allelic exchange mutagenesis. Deletion of cpsG resulted in changes to colony morphology and cell buoyant density, and also significantly decreased galactose content relative to glucose in the capsular polysaccharide as determined by GC-MS, consistent with epimerase activity of CpsG. There was also a metabolic penalty of cpsG knockout revealed by slower growth in complex media, and reduced proliferation in whole fish blood. Moreover, whilst antibodies raised in fish against the wild type cross-reacted in whole cell and cps ELISA, they did not cross-opsonise the mutant in a peripheral blood neutrophil opsonisation assay, consistent with reported vaccine escape. We have shown here that mutation in cpsG results in altered CPS composition and this in turn results in poor cross-opsonisation that explains some of the historic vaccination failure on fish farms in Australia. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  1. Analysis of phenotype, genotype and serotype distribution in erythromycin-resistant group B streptococci isolated from vaginal flora in Southern Ireland.

    LENUS (Irish Health Repository)

    Kiely, R A

    2010-02-01

    The screening of 2000 women of childbearing age in Cork between 2004 and 2006 produced 37 erythromycin-resistant group B streptococcus (GBS) isolates. PCR analysis was performed to determine the basis for erythromycin resistance. The ermTR gene was most frequently expressed (n = 19), followed by the ermB gene (n = 8). Four isolates harboured the mefA gene. Six isolates yielded no PCR products. Some phenotype-genotype correlation was observed. All isolates expressing the mefA gene displayed the M phenotype whilst all those expressing ermB displayed the constitutive macrolide resistance (cMLS(B)) phenotype. Of 19 isolates that expressed the ermTR gene, 16 displayed the inducible macrolide resistance (iMLS(B)) phenotype. Serotype analysis revealed that serotypes III and V predominated in these isolates. The identification of two erythromycin-resistant serotype VIII isolates among this collection represents the first reported finding of erythromycin resistance in this serotype. A single isolate was non-typable using two latex agglutination serotyping kits.

  2. Direct mapping of 19F in 19FDG-6P in brain tissue at subcellular resolution using soft X-ray fluorescence

    Science.gov (United States)

    Poitry-Yamate, C.; Gianoncelli, A.; Kourousias, G.; Kaulich, B.; Lepore, M.; Gruetter, R.; Kiskinova, M.

    2013-10-01

    Low energy x-ray fluorescence (LEXRF) detection was optimized for imaging cerebral glucose metabolism by mapping the fluorine LEXRF signal of 19F in 19FDG, trapped as intracellular 19F-deoxyglucose-6-phosphate (19FDG-6P) at 1μm spatial resolution from 3μm thick brain slices. 19FDG metabolism was evaluated in brain structures closely resembling the general cerebral cytoarchitecture following formalin fixation of brain slices and their inclusion in an epon matrix. 2-dimensional distribution maps of 19FDG-6P were placed in a cytoarchitectural and morphological context by simultaneous LEXRF mapping of N and O, and scanning transmission x-ray (STXM) imaging. A disproportionately high uptake and metabolism of glucose was found in neuropil relative to intracellular domains of the cell body of hypothalamic neurons, showing directly that neurons, like glial cells, also metabolize glucose. As 19F-deoxyglucose-6P is structurally identical to 18F-deoxyglucose-6P, LEXRF of subcellular 19F provides a link to in vivo 18FDG PET, forming a novel basis for understanding the physiological mechanisms underlying the 18FDG PET image, and the contribution of neurons and glia to the PET signal.

  3. Direct mapping of 19F in 19FDG-6P in brain tissue at subcellular resolution using soft X-ray fluorescence

    International Nuclear Information System (INIS)

    Poitry-Yamate, C; Lepore, M; Gruetter, R; Gianoncelli, A; Kourousias, G; Kiskinova, M; Kaulich, B

    2013-01-01

    Low energy x-ray fluorescence (LEXRF) detection was optimized for imaging cerebral glucose metabolism by mapping the fluorine LEXRF signal of 19 F in 19 FDG, trapped as intracellular 19 F-deoxyglucose-6-phosphate ( 19 FDG-6P) at 1μm spatial resolution from 3μm thick brain slices. 19 FDG metabolism was evaluated in brain structures closely resembling the general cerebral cytoarchitecture following formalin fixation of brain slices and their inclusion in an epon matrix. 2-dimensional distribution maps of 19 FDG-6P were placed in a cytoarchitectural and morphological context by simultaneous LEXRF mapping of N and O, and scanning transmission x-ray (STXM) imaging. A disproportionately high uptake and metabolism of glucose was found in neuropil relative to intracellular domains of the cell body of hypothalamic neurons, showing directly that neurons, like glial cells, also metabolize glucose. As 19 F-deoxyglucose-6P is structurally identical to 18 F-deoxyglucose-6P, LEXRF of subcellular 19 F provides a link to in vivo 18 FDG PET, forming a novel basis for understanding the physiological mechanisms underlying the 18 FDG PET image, and the contribution of neurons and glia to the PET signal

  4. Effect of pneumococcal conjugate vaccination on serotype-specific carriage and invasive disease in England: a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Stefan Flasche

    2011-04-01

    Full Text Available BACKGROUND: We investigated the effect of the 7-valent pneumococcal conjugate vaccine (PCV7 programme in England on serotype-specific carriage and invasive disease to help understand its role in serotype replacement and predict the impact of higher valency vaccines. METHODS AND FINDINGS: Nasopharyngeal swabs were taken from children <5 y old and family members (n=400 2 y after introduction of PCV7 into routine immunization programs. Proportions carrying Streptococcus pneumoniae and serotype distribution among carried isolates were compared with a similar population prior to PCV7 introduction. Serotype-specific case carrier ratios (CCRs were estimated using national data on invasive disease. In vaccinated children and their contacts vaccine-type (VT carriage decreased, but was offset by an increase in non-VT carriage, with no significant overall change in carriage prevalence, odds ratio 1.06 (95% confidence interval 0.76-1.49. The lower CCRs of the replacing serotypes resulted in a net reduction in invasive disease in children. The additional serotypes covered by higher valency vaccines had low carriage but high disease prevalence. Serotype 11C emerged as predominant in carriage but caused no invasive disease whereas 8, 12F, and 22F emerged in disease but had very low carriage prevalence. CONCLUSION: Because the additional serotypes included in PCV10/13 have high CCRs but low carriage prevalence, vaccinating against them is likely to significantly reduce invasive disease with less risk of serotype replacement. However, a few serotypes with high CCRs could mitigate the benefits of higher valency vaccines. Assessment of the effect of PCV on carriage as well as invasive disease should be part of enhanced surveillance activities for PCVs. Please see later in the article for the Editors' Summary.

  5. The changing epidemiology of invasive pneumococcal disease in aboriginal and non-aboriginal western Australians from 1997 through 2007 and emergence of nonvaccine serotypes.

    Science.gov (United States)

    Lehmann, Deborah; Willis, Judith; Moore, Hannah C; Giele, Carolien; Murphy, Denise; Keil, Anthony D; Harrison, Catherine; Bayley, Kathy; Watson, Michael; Richmond, Peter

    2010-06-01

    BACKGROUND. In 2001, Australia introduced a unique 7-valent pneumococcal conjugate vaccine (7vPCV) 2-, 4-, and 6-month schedule with a 23-valent pneumococcal polysaccharide vaccine (23vPPV) booster for Aboriginal children, and in 2005, 7vPCV alone in a 2-, 4-, and 6-month schedule for non-Aboriginal children. Aboriginal adults are offered 23vPPV but coverage is poor. We investigated trends in invasive pneumococcal disease (IPD) in Western Australia (WA). METHODS. Enhanced IPD surveillance has been ongoing since 1996. We calculated IPD incidence rates for Aboriginal and non-Aboriginal Australians before and after introduction of 7vPCV. RESULTS. A total of 1792 cases occurred during the period 1997-2007; the IPD incidence rate was 47 cases per 100,000 population per year among Aboriginal people and 7 cases per 100,000 population per year in non-Aboriginal people. After introduction of 7vPCV, IPD rates among Aboriginal children decreased by 46% for those Aboriginal children. IPD rates decreased by >30% in non-Aboriginal people 50 years of age but increased among Aboriginal adults (eg, from 59.1 to 109.6 cases per 100,000 population per year among those 30-49 years of age). Although IPD due to 7vPCV serotypes decreased in all age groups, IPD incidence due to non-7vPCV serotypes increased, and it almost doubled among Aboriginal adults 30-49 years of age (from 48.3 to 97.0 cases per 100,000 population per year). Among non-Aboriginal children, 37% of IPD is now due to serotype 19A. CONCLUSIONS. IPD incidence rates have decreased markedly among children and non-Aboriginal adults with a 3-dose infant 7vPCV schedule. However, IPD due to non-7vPCV serotypes has increased and is of particular concern among young Aboriginal adults, for whom an intensive 23vPPV campaign is needed. An immunization register covering all age groups should be established.

  6. Pneumococcal serotypes and serogroups causing invasive disease in Pakistan, 2005-2013.

    Directory of Open Access Journals (Sweden)

    Sadia Shakoor

    Full Text Available While pneumococcal conjugate vaccines have been implemented in most countries worldwide, use in Asia has lagged in part because of a lack of data on the amount of disease that is vaccine preventable in the region. We describe pneumococcal serotypes elicited from 111 episodes of invasive pneumococcal disease (IPD from 2005 to 2013 among children and adults in Pakistan. Seventy-three percent (n = 81 of 111 IPD episodes were cases of meningitis (n = 76 in children 0-15 years and n = 5 among adults. Serotypes were determined by target amplification of DNA extracted from pneumococcal isolates (n = 52 or CSF specimens (n = 59. Serogroup 18 was the most common serogroup causing meningitis in children <5 years, accounting for 21% of cases (n = 13. The 10-valent pneumococcal conjugate vaccine (PCV 10 or PCV10- related serotypes were found in 61% (n = 47 of childhood (age 0-15 years meningitis episodes. PCV-13 increased this coverage to 63% (one additional serotype 19A; n = 48. Our data indicate that use of PCVs would prevent a large proportion of serious pneumococcal disease.

  7. Properties of polysaccharides in several seaweeds from Atlantic Canada and their potential anti-influenza viral activities

    Science.gov (United States)

    Jiao, Guangling; Yu, Guangli; Wang, Wei; Zhao, Xiaoliang; Zhang, Junzeng; Ewart, Stephen H.

    2012-06-01

    To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae ( Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae ( Ascophyllum nodosum and Fucus vesiculosus), and one green alga ( Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were analyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties.

  8. Antimicrobial resistance and serotyping of Streptococcus pneumoniae isolated from pediatric patients in Belo Horizonte, MG, Brazil Resistência antimicrobiana e sorotipagem de Streptococcus pneumoniae isolado de pacientes pediátricos em Belo Horizonte, MG

    Directory of Open Access Journals (Sweden)

    Ana Paula Gomes de Oliveira Magalhães

    2003-07-01

    Full Text Available Thirty one Streptococcus pneumoniae invasive strains were isolated from a pediatric population in Belo Horizonte from June, 1999 to May, 2001. Penicillin, trimethoprim-sulfamethoxazole, tetracycline and chloramphenicol resistance rates for the isolates were 41.9, 58.1, 25.8 and 3.2%, respectively. Intermediate penicillin resistant (MICs between 0.1 and 1.0 µg/ml and resistant (MICs > 2.0 µg/ml isolates occured at rates of 38.7 and 3.2%, respectively. Resistance to erythromycin, ofloxacin, rifampin or vancomicyn was not detected. Ten S. pneumoniae serotypes (14, 5, 10 A, 6B, 15B, 18C, 6 A, 18 A, 19 A and 19 F were identified. Serotype 14 (12 out of 31 was predominant among the isolates. Penicillin and trimethoprim-sulfamethoxazole resistance was more common in 14 and 6B serotypes.Trinta e três linhagens invasivas do S. pneumoniae foram isoladas a partir de pacientes pediátricos em Belo Horizonte, MG, Brasil, de junho de 1999 a maio de 2001. As taxas de resistência à penicilina, ao trimetoprim-sultametoxazol, tetraciclina e cloranfenicol foram respectivamente, 41, 9; 58,1 e 3,2%. A resistência intermediária à penicilina (MICs entre 0,1 e 1,0 µg/ml e resistência total (MICs>2.0 µg/ml ocorreram, respectivamente, nas porcentagens de 38,7 e 3,2%. Não foi detectada resistência à eritromicina, ofloxacin, rifampina e vancomicina. Foram identificados 9 sorotipos do S. pneumoniae (14, 5, 10 , 6B, 15B, 18C, 6 A, 18 19 A e 19F entre os isolados. O sorotipo 14 (12 de 31 foi predominate entre os isolados. A resistência à penicilina e ao trimetoprim-sulfametoxazol estava sempre associada aos sorotipos 14 e 6B.

  9. Polyarticular Septic Arthritis Caused by Haemophilus influenzae Serotype f in an 8-Month-Old Immunocompetent Infant: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Raheel Ahmed Ali

    2015-01-01

    Full Text Available Background. The standard use of vaccinations against pathogens has resulted in a decreased incidence of musculoskeletal infections caused by these previously common bacterial pathogens. Consequently, the incidence of infections caused by atypical bacteria is rising. This report presents a case of septic arthritis caused by non-type b H. influenzae in a pediatric patient. Methods. We report a case of an infant with polyarticular septic arthritis caused by H. influenzae serotype f. A literature review was conducted with the inclusion criteria of case reports and studies published between 2004 and 2013 addressing musculoskeletal H. influenzae infections. Results. An 8-month-old female presented with pain and swelling in her right ankle and left elbow. The patient was diagnosed with septic arthritis and underwent incision and drainage. Wound and blood cultures were positive for Haemophilus influenzae serotype f. In addition to treatment with IV antibiotics, the patient underwent immunocompetency studies, which were normal. Subsequent follow-up revealed eradication of the infection. Conclusions. Haemophilus influenzae non-type b may cause serious invasive infections such as sepsis or septic arthritis in children with or without predisposing factors such as immunodeficiency or asplenia. Optimal treatment includes surgical management, culture driven IV antibiotics, and an immunologic workup.

  10. Measurement of the 19F(n,2n)18F cross section from 18 to 27 MeV

    International Nuclear Information System (INIS)

    Hartmann, C.L.; DeLuca, P.M. Jr.

    1990-01-01

    the 19 F(n,2n) 18 F cross section was measured at neutron energies of 18, 21, 23, and 27 MeV. Nearly monoenergetic neutrons bombarded teflon (CF 2 ), Zr, and Au samples. 19 F(n,2n) 18 F cross section values were determined relative to nat Zr(n,xn) 89 Zr and 197 Au(n,2n) 196 Au from measurements of the 18 F, 89 Zr, and 196 Au activities. Our results are in agreement with previous measurements below 20 MeV and extend the usefulness of this reaction to 27 MeV. 22 refs., 1 fig., 2 tabs

  11. Genesis of a novel Shigella flexneri serotype by sequential infection of serotype-converting bacteriophages SfX and SfI

    Directory of Open Access Journals (Sweden)

    Sun Qiangzheng

    2011-12-01

    Full Text Available Abstract Background Shigella flexneri is the major pathogen causing bacillary dysentery. Fifteen serotypes have been recognized up to now. The genesis of new S. flexneri serotypes is commonly mediated by serotype-converting bacteriophages. Untypeable or novel serotypes from natural infections had been reported worldwide but have not been generated in laboratory. Results A new S. flexneri serotype-serotype 1 d was generated when a S. flexneri serotype Y strain (native LPS was sequentially infected with 2 serotype-converting bacteriophages, SfX first and then SfI. The new serotype 1 d strain agglutinated with both serotype X-specific anti-7;8 grouping serum and serotype 1a-specific anti- I typing serum, and differed from subserotypes 1a, 1b and 1c. Twenty four S. flexneri clinical isolates of serotype X were all converted to serotype 1 d by infection with phage SfI. PCR and sequencing revealed that SfI and SfX were integrated in tandem into the proA-yaiC region of the host chromosome. Conclusions These findings suggest a new S. flexneri serotype could be created in nature. Such a conversion may be constrained by susceptibility of a strain to infection by a given serotype-converting bacteriophage. This finding has significant implications in the emergence of new S. flexneri serotypes in nature.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Chrispin Chaguza

    2016-09-01

    Full Text Available 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.

  14. Theoretical conformational analysis of the tetrasaccharide repeating units of the O-antigenic polysaccharide of Shigella flexneri

    International Nuclear Information System (INIS)

    Lipkind, G.M.; Kochetkov, N.K.

    1986-01-01

    A theoretical conformational analysis has been made of the four tetrasaccharide repeating units of the polysaccharide of Shigella flexneri, serotype Y. The interdependence of the conformation states of the neighboring disaccharide units and the oligosaccharides has been investigated. The distribution of the tetrasaccharides over the conformations in solution obtained by calculating the free energies of the optimum structures is given. It has been shown that a substantial correction of the results relating to oligosaccharide chains is achieved when the entropy factors is taken into account

  15. Characteristic of resistant ionization-radiation and its relationship with polysaccharide contents in spirulina

    International Nuclear Information System (INIS)

    Wang Zhiping; Xu Bujin

    2001-01-01

    The anti-radiation capacities of intact filaments, no-sheath filaments and cells of 4 kinds of Spiralina strains (Ss-V, Sp-F, Sp-Z and Sp-D) treated by "6"0Co γ-rays were studied. The relationship between polysaccharide contents and anti-radiation capacity of 4 strains were also detected. The results showed that Spirulina is highly resistant toγ-radiation, however there were significant differences with various strains. The order of anti-radiation capacity is Ss-V > Sp-F > Sp-Z > Sp-D. Moreover, the anti-radiation capacity were remarkably related with polysaccharide contents in the 4 strains. This showed that polysaccharide is very important for raising and maintain-ing super anti-radiation capacity in Spiralina. (authors)

  16. Chemical profile of a polysaccharide from Psidium guajava leaves and it's in vivo antitussive activity.

    Science.gov (United States)

    Khawas, Sadhana; Sivová, Veronika; Anand, Namrata; Bera, Kaushik; Ray, Bimalendu; Nosáľová, Gabriela; Ray, Sayani

    2018-04-01

    Decoction of Psidium guajava leaves has been used as medication for chronic coughs and breathlessness for ages. Despite demonstration of antitussive activity, the specific molecule responsible for this remains unidentified. Herein, we report chemical profile and antitussive activity of its water extract (WE) and a polysaccharide (F1) present therein. This polysaccharide (F1), purified from WE by precipitation with ethanol and then through Cu(II)acetate, contains Ara, Gal, Rha, Glc and GalA residues, and has a molecular mass of 156 kDa. It comprises of terminal-, (1,5)- and (1,3,5)-linked Araf; (1,3)-, (1,6)- and (1,3,6)-linked Galp alongside (1,2)- and (1,2,4)-linked Rhap residues. Oligosaccharides indicating polysaccharide structure have been generated by Smith degradation and characterized. The WE fraction suppressed citric acid induced cough efforts in guinea pigs in the dose of 50 mg kg -1 . Assessment of antitussive activity of fractions prepared from WE namely F1 (polysaccharide) and F2 (ethanol soluble fraction) revealed that polysaccharide is the active component. Remarkably, tested samples do not alter the specific airway smooth muscle reactivity in animals significantly. The simple extraction method, prominent activity and favorable reactions profile suggest that this macromolecule could be an antitussive drug candidate. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. 19F labelled dextrans and antibodies as NMR imaging and spectroscopy agents

    International Nuclear Information System (INIS)

    Antich, P.P.; Kulkarni, P.V.

    1993-01-01

    A method is described of NMR imaging or spectroscopy, comprising the steps of administering to a living subject a 19 F labelled NMR agent, the NMR agent comprising (a) a transport polymer selected from the group consisting of dextran polymers and amino dextrans, having a molecular weight between approximately 100 d and 500 kd, and antibodies and fragments thereof, and (b) a 19F-containing sensor moiety selected from the group consisting of fluorinated alkyls, fluorinated acetates, fluoroaniline, and fluoroalkyl phosphonates, in an amount effective to provide a detectable NMR signal; and then detecting the 19 F NMR signal produced

  18. [Primary study on fluro [ 19F] berberine derivative for human hepatocellular carcinoma targetting in vitro].

    Science.gov (United States)

    Zhang, Tong; Wu, Xiaoai; Cai, Huawei; Liang, Meng; Fan, Chengzhong

    2017-04-01

    [ 18 F]HX-01, a Fluorine-18 labeled berberine derivative, is a potential positron emission tomography (PET) tumor imaging agent, while [ 19 F]HX-01 is a nonradioactive reference substance with different energy state and has the same physical and chemical properties. In order to collect data for further study of [ 18 F]HX-01 PET imaging of hepatocellular carcinoma in vivo , this study compared the uptake of [ 19 F]HX-01 by human hepatocellular carcinoma and normal hepatocytes in vitro . The target compound, [ 19 F]HX-01, was synthesized in one step using berberrubine and 3-fluoropropyl 4-methylbenzenesulfonate. Cellular uptake and localization of [ 19 F]HX-01 were performed by a fluorescence microscope in human hepatocellular carcinoma HepG2, SMMC-7721 and human normal hepatocyte HL-7702. Cellular proliferation inhibition and cell cytotoxicity assay of the [ 19 F]HX-01 were conducted using cell counting kit-8 (CCK-8) on HepG2, SMMC-7721 and HL-7702 cells. Fluorescent microscopy showed that the combining ability of [ 19 F]HX-01 to the carcinoma SMMC-7721 and HepG2 was higher than that to the normal HL-7702. Cellular proliferation inhibition assay demonstrated that [ 19 F]HX-01 leaded to a dose-dependent inhibition on SMMC-7721, HepG2, and HL-7702 proliferation. Cell cytotoxicity assay presented that the cytotoxicity of [ 19 F]HX-01 to SMMC-7721 and HepG2 was obviously higher than that to HL-7702. This in vitro study showed that [ 19 F]HX-01 had a higher selectivity on human hepatocellular carcinoma cells (SMMC-7721, HepG2) but has less toxicity to normal hepatocytes (HL-7702). This could set up the idea that the radioactive reference substance [ 18 F]HX-01 may be worthy of further development as a potential molecular probe targeting human hepatocellular carcinoma using PET.

  19. Improved antimelanogenesis and antioxidant effects of polysaccharide from Cuscuta chinensis Lam seeds after enzymatic hydrolysis.

    Science.gov (United States)

    Liu, Zi-Jun; Wang, Ya-Lan; Li, Qi-Ling; Yang, Liu

    2018-01-01

    Cuscuta chinensis polysaccharide (CPS) was extracted using hot water and enzymatically hydrolyzed C. chinensis polysaccharide (ECPS) was produced by the mannase enzymatic hydrolysis process. The purpose of this research was to investigate the antimelanogenic activity of ECPS and CPS in B16F10 melanoma cells. The in vitro antioxidant activity was assessed by their ferric iron reducing power and DPPH free radical scavenging activities. The molecular mass distribution of polysaccharides was determined using SEC-MALLS-RI. CPS was successfully enzymatically degraded using mannase and the weighted average molecular weights of CPS and ECPS were 434.6 kDa and 211.7 kDa. The results of biological activity assays suggested that the enzymatically hydrolyzed polysaccharide had superior antimelanogenic activity and antioxidant effect than the original polysaccharide. ECPS exhibited antimelanogenic activity by down-regulating the expression of tyrosinase, MITF, and TRP-1 without cytotoxic effects in B16F10 melanoma cells. In conclusion, ECPS have the potential to become a skin whitening product.

  20. Tank 18-F And 19-F Tank Fill Grout Scale Up Test Summary

    International Nuclear Information System (INIS)

    Stefanko, D.; Langton, C.

    2012-01-01

    High-level waste (HLW) tanks 18-F and 19-F have been isolated from FTF facilities. To complete operational closure the tanks will be filled with grout for the purpose of: (1) physically stabilizing the tanks, (2) limiting/eliminating vertical pathways to residual waste, (3) entombing waste removal equipment, (4) discouraging future intrusion, and (5) providing an alkaline, chemical reducing environment within the closure boundary to control speciation and solubility of select radionuclides. This report documents the results of a four cubic yard bulk fill scale up test on the grout formulation recommended for filling Tanks 18-F and 19-F. Details of the scale up test are provided in a Test Plan. The work was authorized under a Technical Task Request (TTR), HLE-TTR-2011-008, and was performed according to Task Technical and Quality Assurance Plan (TTQAP), SRNL-RP-2011-00587. The bulk fill scale up test described in this report was intended to demonstrate proportioning, mixing, and transportation, of material produced in a full scale ready mix concrete batch plant. In addition, the material produced for the scale up test was characterized with respect to fresh properties, thermal properties, and compressive strength as a function of curing time.

  1. TANK 18-F AND 19-F TANK FILL GROUT SCALE UP TEST SUMMARY

    Energy Technology Data Exchange (ETDEWEB)

    Stefanko, D.; Langton, C.

    2012-01-03

    High-level waste (HLW) tanks 18-F and 19-F have been isolated from FTF facilities. To complete operational closure the tanks will be filled with grout for the purpose of: (1) physically stabilizing the tanks, (2) limiting/eliminating vertical pathways to residual waste, (3) entombing waste removal equipment, (4) discouraging future intrusion, and (5) providing an alkaline, chemical reducing environment within the closure boundary to control speciation and solubility of select radionuclides. This report documents the results of a four cubic yard bulk fill scale up test on the grout formulation recommended for filling Tanks 18-F and 19-F. Details of the scale up test are provided in a Test Plan. The work was authorized under a Technical Task Request (TTR), HLE-TTR-2011-008, and was performed according to Task Technical and Quality Assurance Plan (TTQAP), SRNL-RP-2011-00587. The bulk fill scale up test described in this report was intended to demonstrate proportioning, mixing, and transportation, of material produced in a full scale ready mix concrete batch plant. In addition, the material produced for the scale up test was characterized with respect to fresh properties, thermal properties, and compressive strength as a function of curing time.

  2. ROLE OF STREPTOCOCCUS PNEUMONIAE IN THE STRUCTURE OF BACTERIAL INFECTIONS IN THE CHILDREN HOSPITALIZED TO INPATIENT HOSPITALS IN MOSCOW IN 2011–2012

    Directory of Open Access Journals (Sweden)

    A. A. Baranov

    2013-01-01

    Full Text Available Data on the spread of Streptococcus pneumoniae serotypes in the RF are extremely limited. 3 pneumococcal conjugated vaccines are approved inRussia; however, neither has yet been employed in the framework of the national population immunization program. At the same time, it is the dataon the serotype range of pneumococcal infections that may be considered the prognostic efficacy criterion for the national vaccination programs.The objective of this research is identification of the circulating S. pneumoniae serotypes and spread of pneumococcal etiology infections in the structure of bacterial infections in the infants hospitalized to 5 inpatient hospital of Moscow in 2011–2012. The trial involved 864 patients in tote. Vast majority of patients (86% had acute purulent otitis media and sinusitis. Community-acquired pneumonia was diagnosed in 9% of patients, sepsis and bacteremia — in 3.6%; purulent meningitis — 1.2% of patients. It has been revealed that S. pneumoniae is the primary pathogen in the structure of nasopharyngeal carriage in the children under 5 years of age hospitalized with acute bacterial infections, and the primary bacterial causative agent of acute otitis media at this age. Nasopharyngeal pneumococcal carriage analysis revealed the prevalent serotypes19F, 14, 23F, 3, 6A and B; they were present in 3/4 of all cases; 19F was the most frequent (> 20%. Diversity of the S. pneumoniae serotypes detected in middle ear liquid was less significant — 17 serotypes (in comparison with 24 serotypes in nasopharynx. The 5 prevalent serotypes were 19F, 3, 14, 23F, 6B and 19A (> 75% in tote. Detection rate of serotypes 3 and 19A in middle ear liquid significantly exceeded the detection rate of these serotypes in case of nasopharyngeal carriage. The study of invasive infections revealed serotypes 14, 23F, 3 and 15C. These data may be used as a benchmark for future monitoring and evaluation of effect of PCV vaccines on epidemiology of

  3. Serotipos prevalentes de Streptococcus pneumoniae colonizadores de nasofaringe, en niños del Distrito Federal Prevalence of Streptococcus pneumoniae serotypes on nasopharyngeal colonization in children of Mexico City

    Directory of Open Access Journals (Sweden)

    Fortino Solórzano-Santos

    2005-07-01

    Full Text Available OBJETIVO: Determinar frecuencia, serotipos y susceptibilidad a ocho antimicrobianos en Streptococcus pneumoniae aislados de la nasofaringe de una muestra representativa de niños menores de cinco años de edad residentes en el Distrito Federal. MATERIAL Y MÉTODOS: Estudio transversal, hecho de febrero de 2002 a enero de 2003. Se incluyeron niños de 2 meses a 5 años. A los seleccionados se les tomó una muestra de exudado faríngeo con hisopo de alginato de calcio. Bajo técnicas ya establecidas se realizó identificación, tipificación y susceptibilidad a ocho antimicrobianos de los aislamientos de S. pneumoniae. Se utilizó estadística descriptiva, prueba de Ji cuadrada y razón de momios (IC 95% para los factores de riesgo. RESULTADOS: Se estudiaron 573 niños. En 122/573 (21.4% niños se aisló S. pneumoniae. Los serotipos más frecuentes fueron el 23F, 35, 19F, 11A y 15A; 46% de los serotipos encontrados no son cubiertos con la vacuna heptavalente. Se encontró 12% de susceptibilidad reducida a la penicilina, con 3% de cepas con alta resistencia; la resistencia a eritromicina fue >30% y para trimetoprim-sulfametoxazol (TMP/SMX >40%. No hubo cepas resistentes a vancomicina, cefotaxima, amoxicilina-clavulanato, cloranfenicol o ampicilina. CONCLUSIONES: El porcentaje de serotipos de S. pneumoniae en portadores nasofaríngeos no cubiertos por la vacuna heptavalente es alto, y la resistencia a macrólidos y TMP/SMX es elevada, lo que debe alertar al grupo médico.OBJECTIVE: To determine the frequency, serotypes and susceptibility profiles to eight antimicrobials in Streptococcus pneumoniae nasopharyngeal isolates from a representative sample of children under 5 years of age, residents of Mexico City. PATIENTS AND METHODS: A cross-sectional survey was conducted in 573 children aged 2 months to 5 years. A nasopharyngeal sample was taken. S. pneumoniae identification, capsular serotyping and antimicrobial susceptibility to eight antimicrobials

  4. Analysis of the capsular polysaccharide biosynthesis locus of Porphyromonas gingivalis and development of a K1-specific polymerase chain reaction-based serotyping assay

    NARCIS (Netherlands)

    Brunner, J.; Crielaard, W.; Winkelhoff A.J. van

    2008-01-01

    Background and Objective: Porphyromonas gingivalis is a gram-negative obligate anaerobe that is strongly associated with severe periodontitis. Previous reports showed an association of P. gingivalis capsular polysaccharide with virulence. The K1 capsular polysaccharide was found to be more

  5. Streptococcus agalactiae isolates of serotypes Ia, III and V from human and cow are able to infect tilapia.

    Science.gov (United States)

    Chen, Ming; Wang, Rui; Luo, Fu-Guang; Huang, Yan; Liang, Wan-Wen; Huang, Ting; Lei, Ai-Ying; Gan, Xi; Li, Li-Ping

    2015-10-22

    Recent studies have shown that group B streptococcus (GBS) may be infectious across hosts. The purpose of this study is to investigate the pathogenicity of clinical GBS isolates with serotypes Ia, III and V from human and cow to tilapia and the evolutionary relationship among these GBS strains of different sources. A total of 27 clinical GBS isolates from human (n=10), cow (n=2) and tilapia (n=15) were analyzed using serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Among them, 15 isolates were tested for their pathogenicity to tilapia. The results showed that five human GBS strains (2 serotype III, 2 serotype Ia and 1 serotype V) infected tilapia with mortality rate ranging from 56.67% to 100%, while the other five human GBS strains tested were unable to infect tilapia. In addition, two cow GBS strains C001 and C003 of serotype III infected tilapia. However, they had significantly lower pathogenicity than the five human strains. Furthermore, human GBS strains H005 and H008, which had very strong ability to infect tilapia, had the same PFGE pattern. MLST analysis showed that the five human and the two cow GBS strains that were able to infect tilapia belonged to clonal complexes CC19, CC23 and CC103. The study for the first time confirmed that human or cow GBS clonal complexes CC19, CC23 and CC103 containing strains with serotypes Ia, III and V could infect tilapia and induce clinical signs under experimental conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Identification and characterization of multidrug-resistant Salmonella enterica serotype Albert isolates in the United States.

    Science.gov (United States)

    Folster, Jason P; Campbell, Davina; Grass, Julian; Brown, Allison C; Bicknese, Amelia; Tolar, Beth; Joseph, Lavin A; Plumblee, Jodie R; Walker, Carrie; Fedorka-Cray, Paula J; Whichard, Jean M

    2015-05-01

    Salmonella enterica is one of the most common causes of bacterial foodborne illness in the United States. Although most Salmonella infections are self-limiting, antimicrobial treatment of invasive salmonellosis is critical. The primary antimicrobial treatment options include fluoroquinolones or extended-spectrum cephalosporins, and resistance to these antimicrobial drugs may complicate treatment. At present, S. enterica is composed of more than 2,600 unique serotypes, which vary greatly in geographic prevalence, ecological niche, and the ability to cause human disease, and it is important to understand and mitigate the source of human infection, particularly when antimicrobial resistance is found. In this study, we identified and characterized 19 S. enterica serotype Albert isolates collected from food animals, retail meat, and humans in the United States during 2005 to 2013. All five isolates from nonhuman sources were obtained from turkeys or ground turkey, and epidemiologic data suggest poultry consumption or live-poultry exposure as the probable source of infection. S. enterica serotype Albert also appears to be geographically localized to the midwestern United States. All 19 isolates displayed multidrug resistance, including decreased susceptibility to fluoroquinolones and resistance to extended-spectrum cephalosporins. Turkeys are a likely source of multidrug-resistant S. enterica serotype Albert, and circulation of resistance plasmids, as opposed to the expansion of a single resistant strain, is playing a role. More work is needed to understand why these resistance plasmids spread and how their presence and the serotype they reside in contribute to human disease. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  7. Antibiotic of resistence profile of Salmonella spp. serotypes isolated from retail beef in Mexico City.

    OpenAIRE

    Nova Nayarit-Ballesteros; María Salud Rubio-Lozano; Enrique Delgado-Suárez; Danilo Méndez-Medina; Diego Braña-Varela; Oscar Rodas-Suárez

    2016-01-01

    Objective. To determine the serotype and antibiotic resistance profile of Salmonella spp. isolated from retail ground beef in Mexico City. Materials and methods. A total of 100 samples of ground beef were analyzed. The pathogen was isolated by conventional methods and confirmed by PCR (invA gene, 284 bp). The antibiotic resistance profile was determined by the Kirby-Bauer method while serotyping was performed according to the Kauffman-White scheme. Results. We isolated a total of 19 strains o...

  8. Extraction and antioxidation of polysaccharide from porphyra haitanensis using response surface method

    International Nuclear Information System (INIS)

    Cai, C.; Yang, Y.; Zhao, M.; Jia, R.; He, P.

    2017-01-01

    This paper deals with the preparation and antioxidation of polysaccharide from Porphyra haitanensis. The ratio of water to raw material, extraction temperature and extraction time were taken in sequence as independent variables in single factor test, and polysaccharide yield as response value. Using Box-Benhnken central combination experimental design principles and response surface methodology, interactions of variables and their influence on polysaccharide yield of P. haitanensis were studied and the prediction model of quadratic polynomial regression equation was inferred by simulation, in which the optimum parameters for preparing polysaccharide from P. haitanensis were 88.4°C of extraction temperature, 1.97 h of extraction time and 40:1 (ml/g) of ratio of water to raw material, and polysaccharide of 15.19 % in yield from P. haitanensis was verified after two parallel test. Furthermore, the polysaccharide of P. haitanensis showed good antioxidant capacity which could be used as potential natural antioxidant products in food additives industries. (author)

  9. Production and characterization of the polysaccharide ''xanthan gum ...

    African Journals Online (AJOL)

    use

    2011-11-23

    Nov 23, 2011 ... microbial polysaccharide (Paul et al., 1986) is produced by microbial ... production basic medium composed of the following (g/l), K2HPo4, .... Dubois M, Gilles KA, Hamilton JK, Roberts PA, Smith F (1956). ... John Wiley and.

  10. Synthesis and Characterization of a Magnetically Active 19F Molecular Beacon.

    Science.gov (United States)

    Dempsey, Megan E; Marble, Hetal D; Shen, Tun-Li; Fawzi, Nicolas L; Darling, Eric M

    2018-02-21

    Gene expression is used extensively to describe cellular characteristics and behaviors; however, most methods of assessing gene expression are unsuitable for living samples, requiring destructive processes such as fixation or lysis. Recently, molecular beacons have become a viable tool for live-cell imaging of mRNA molecules in situ. Historically, beacon-mediated imaging has been limited to fluorescence-based approaches. We propose the design and synthesis of a novel molecular beacon for magnetic resonance detection of any desired target nucleotide sequence. The biologically compatible synthesis incorporates commonly used bioconjugation reactions in aqueous conditions and is accessible for laboratories without extensive synthesis capabilities. The resulting beacon uses fluorine ( 19 F) as a reporter, which is broadened, or turned "off", via paramagnetic relaxation enhancement from a stabilized nitroxide radical spin label when the beacon is not bound to its nucleic acid target. Therefore, the 19 F NMR signal of the beacon is quenched in its hairpin conformation when the spin label and the 19 F substituent are held in proximity, but the signal is recovered upon beacon hybridization to its specific complementary nucleotide sequence by physical separation of the radical from the 19 F reporter. This study establishes a path for magnetic resonance-based assessment of specific mRNA expression, providing new possibilities for applying molecular beacon technology in living systems.

  11. Serotipos de neumococo en niños portadores antes de la vacunación antineumocócica en el Perú Pneumococcal serotypes in carrier children prior to the introduction of anti-pneumococcal vaccines in Peru

    Directory of Open Access Journals (Sweden)

    Erik H. Mercado

    2012-03-01

    Full Text Available Objetivos. Determinar la frecuencia y distribución de serotipos de S. pneumoniae en portadores nasofaríngeos sanos menores de dos años previa al uso universal de la vacuna conjugada antineumocócica en el Perú. Materiales y métodos. Entre los años 2007 y 2009 se tomaron muestras de hisopado nasofaríngeo a 2123 niños sanos entre 2 y 24 meses de edad en los consultorios de crecimiento y desarrollo o vacunación de hospitales y centros de salud de siete ciudades del Perú: costa (Lima, Piura; sierra (Cusco, Abancay, Arequipa y Huancayo y selva (Iquitos. Las cepas de neumococo fueron aisladas e identificadas en el laboratorio central del proyecto en Lima y serotipificadas por reacción de Quellung en el Laboratorio de Referencia de Neumococo del Centro de Control y Prevención de Enfermedades. Resultados. Se encontró 27,0% (573/2123 de portadores nasofaríngeos sanos de neumococo. En las 526 cepas analizadas se encontraron 42 serotipos; los más frecuentes fueron: 19F (18,1%, 6B (14,3%; 23F (8,9% y 14 (6,5%. Conclusiones. La distribución de serotipos vacunales en las cepas analizadas fue de 50,0% para los serotipos presentes en la vacuna conjugada heptavalente; 50,2% para los serotipos presentes en la vacuna decavalente y 57,2% para la vacuna 13-valente.Objectives. To determine the carriage rate and serotype distribution of Streptococcus pneumoniae in the nasopharynx of healthy children younger than 2 years prior to the universal use of the pneumococcal conjugate vaccines in Peru. Materials and methods. Between 2007 and 2009 we collected nasopharyngeal swab samples from 2,123 healthy children aged 2 to 24 months in the vaccination and healthy children consultation offices of pediatric hospitals and health centers in 7 cities in Peru: on the coast (Lima, Piura, highlands (Cusco, Abancay, Arequipa and Huancayo and amazon basin (Iquitos. The pneumococcal strains were isolated and identified at the central laboratory of the project in Lima

  12. Population biology of Streptococcus pneumoniae in West Africa: multilocus sequence typing of serotypes that exhibit different predisposition to invasive disease and carriage.

    Directory of Open Access Journals (Sweden)

    Eric S Donkor

    Full Text Available Little is known about the population biology of Streptococcus pneumoniae in developing countries, although the majority of pneumococcal infections occur in this setting. The aim of the study was to apply MLST to investigate the population biology of S. pneumoniae in West Africa.Seventy three invasive and carriage S. pneumoniae isolates from three West African countries including The Gambia, Nigeria and Ghana were investigated. The isolates covered seven serotypes (1, 3, 5, 6A, 11, 14, 23F and were subjected to multilocus sequence typing and antibiotic susceptibility testing.Overall, 50 different sequence types (STs were identified, of which 38% (29 were novel. The most common ST was a novel clone-ST 4012 (6.5%, and some clones including STs 913, 925, 1737, 2160 and 3310 appeared to be specific to the study region. Two STs including ST 63 and ST 4012 were associated with multiple serotypes indicating a history of serotype switching. ST 63 was associated with serotypes 3 and 23F, while ST 4012 was associated with serotypes 6A and 23. eBURST analyses using the stringent 6/7 identical loci definition grouped the 50 STs into 5 clonal complexes and 65 singletons, expressing a high level of genetic diversity among the isolates. Compared to the other serotypes, serotypes 1 and 5 isolates appeared to be more clonal. Internationally recognized antibiotic resistant clones of S. pneumoniae were generally absent in the population investigated and the only multidrug resistant isolate identified (1/66 belong to the Pneumocococcal Epidemiology Network clone ST 63.The pneumococcal population in West Africa is quite divergent, and serotypes that are common in invasive disease (such as serotypes 1 and 5 are more likely to be clonal than serotypes that are common in carriage.

  13. No long-term evidence of hyporesponsiveness after use of pneumococcal conjugate vaccine in children previously immunized with pneumococcal polysaccharide vaccine.

    Science.gov (United States)

    Licciardi, Paul V; Toh, Zheng Quan; Clutterbuck, Elizabeth A; Balloch, Anne; Marimla, Rachel A; Tikkanen, Leena; Lamb, Karen E; Bright, Kathryn J; Rabuatoka, Uraia; Tikoduadua, Lisi; Boelsen, Laura K; Dunne, Eileen M; Satzke, Catherine; Cheung, Yin Bun; Pollard, Andrew J; Russell, Fiona M; Mulholland, Edward K

    2016-06-01

    A randomized controlled trial in Fiji examined the immunogenicity and effect on nasopharyngeal carriage after 0, 1, 2, or 3 doses of 7-valent pneumococcal conjugate vaccine (PCV7; Prevnar) in infancy followed by 23-valent pneumococcal polysaccharide vaccine (23vPPV; Pneumovax) at 12 months of age. At 18 months of age, children given 23vPPV exhibited immune hyporesponsiveness to a micro-23vPPV (20%) challenge dose in terms of serotype-specific IgG and opsonophagocytosis, while 23vPPV had no effect on vaccine-type carriage. This follow-up study examined the long-term effect of the 12-month 23vPPV dose by evaluating the immune response to 13-valent pneumococcal conjugate vaccine (PCV13) administration 4 to 5 years later. Blood samples from 194 children (now 5-7 years old) were taken before and 28 days after PCV13 booster immunization. Nasopharyngeal swabs were taken before PCV13 immunization. We measured levels of serotype-specific IgG to all 13 vaccine serotypes, opsonophagocytosis for 8 vaccine serotypes, and memory B-cell responses for 18 serotypes before and after PCV13 immunization. Paired samples were obtained from 185 children. There were no significant differences in the serotype-specific IgG, opsonophagocytosis, or memory B-cell response at either time point between children who did or did not receive 23vPPV at 12 months of age. Nasopharyngeal carriage of PCV7 and 23vPPV serotypes was similar among the groups. Priming with 1, 2, or 3 PCV7 doses during infancy did not affect serotype-specific immunity or carriage. Immune hyporesponsiveness induced by 23vPPV in toddlers does not appear to be sustained among preschool children in this context and does not affect the pneumococcal carriage rate in this age group. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  14. Otitis-Prone Children Produce Functional Antibodies to Pneumolysin and Pneumococcal Polysaccharides.

    Science.gov (United States)

    Kirkham, Lea-Ann S; Wiertsema, Selma P; Corscadden, Karli J; Mateus, Tulia; Mullaney, Gemma L; Zhang, Guicheng; Richmond, Peter C; Thornton, Ruth B

    2017-03-01

    The pneumococcus is a major otitis media (OM) pathogen, but data are conflicting regarding whether otitis-prone children have impaired humoral immunity to pneumococcal antigens. We and others have shown that otitis-prone and healthy children have similar antibody titers to pneumococcal proteins and polysaccharides (vaccine and nonvaccine types); however, the quality of antibodies from otitis-prone children has not been investigated. Antibody function, rather than titer, is considered to be a better correlate of protection from pneumococcal disease. Therefore, we compared the capacities of antibodies from otitis-prone (cases) and healthy (controls) children to neutralize pneumolysin, the pneumococcal toxin currently in development as a vaccine antigen, and to opsonize pneumococcal vaccine and nonvaccine serotypes. A pneumolysin neutralization assay was conducted on cholesterol-depleted complement-inactivated sera from 165 cases and 61 controls. A multiplex opsonophagocytosis assay (MOPA) was conducted on sera from 20 cases and 20 controls. Neutralizing and opsonizing titers were calculated with antigen-specific IgG titers to determine antibody potency for pneumolysin, pneumococcal conjugate vaccine (PCV) polysaccharides, and non-PCV polysaccharides. There was no significant difference in antibody potencies between cases and controls for the antigens tested. Antipneumolysin neutralizing titers increased with the number of episodes of acute OM, but antibody potency did not. Pneumolysin antibody potency was lower in children colonized with pneumococci than in noncarriers, and this was significant for the otitis-prone group ( P otitis-prone children demonstrates that they respond to the current PCV and are likely to respond to pneumolysin-based vaccines as effectively as healthy children. Copyright © 2017 Kirkham et al.

  15. Electronic stopping powers for fluorine ions in 19F+-implanted silver gallium diselenide

    International Nuclear Information System (INIS)

    Liu Xiangdong; Xia Yueyuan; Li Feng; Lu Qingming; Huang Boda

    2004-01-01

    Electronic stopping powers for 80-350 keV 19 F ions in AgGaSe 2 were obtained by range measurement. Depth profiles of 19 F in AgGaSe 2 were measured by using the 19 F(p,αγ) 16 O resonant nuclear reaction at E R =872.1 keV. A proper convolution calculation method was used to extract the true distribution of fluorine from the experimental excitation yield curves. The electronic stopping powers were derived through fitting the projected range distributions, simulated by using the TRIM/XLL code, to the experimentally measured range distributions. The electronic stopping cross-sections were compared with those obtained from Monte Carlo simulation codes

  16. Rachmaninoff. Sonate für Violoncello und Klavier op. 19 / Giselher Schubert

    Index Scriptorium Estoniae

    Schlüren, Christoph

    1995-01-01

    Uuest heliplaadist "Rachmaninoff. Sonate für Violoncello und Klavier op. 19; Schnittke. Sonate für Violoncello und Klavier; Pärt. Fratres für Violoncello und Klavier. Jiri Barta (Violoncello), Marian Lap£ansky (Klavier). Supraphon/Koch CD 11 2156-2 (WD: 73'13")

  17. Polysaccharides purified from wild Cordyceps activate FGF2/FGFR1c signaling

    Science.gov (United States)

    Zeng, Yangyang; Han, Zhangrun; Yu, Guangli; Hao, Jiejie; Zhang, Lijuan

    2015-02-01

    Land animals as well as all organisms in ocean synthesize sulfated polysaccharides. Fungi split from animals about 1.5 billion years ago. As fungi make the evolutionary journey from ocean to land, the biggest changes in their living environment may be a sharp decrease in salt concentration. It is established that sulfated polysaccharides interact with hundreds of signaling molecules and facilitate many signaling transduction pathways, including fibroblast growth factor (FGF) and FGF receptor signaling pathway. The disappearance of sulfated polysaccharides in fungi and plants on land might indicate that polysaccharides without sulfation might be sufficient in facilitating protein ligand/receptor interactions in low salinity land. Recently, it was reported that plants on land start to synthesize sulfated polysaccharides in high salt environment, suggesting that fungi might be able to do the same when exposed in such environment. Interestingly, Cordyceps, a fungus habituating inside caterpillar body, is the most valued traditional Chinese Medicine. One of the important pharmaceutical active ingredients in Cordyceps is polysaccharides. Therefore, we hypothesize that the salty environment inside caterpillar body might allow the fungi to synthesize sulfated polysaccharides. To test the hypothesis, we isolated polysaccharides from both lava and sporophore of wild Cordyceps and also from Cordyceps militaris cultured without or with added salts. We then measured the polysaccharide activity using a FGF2/FGFR1c signaling-dependent BaF3 cell proliferation assay and found that polysaccharides isolated from wild Cordyceps activated FGF2/FGFR signaling, indicating that the polysaccharides synthesized by wild Cordyceps are indeed different from those by the cultured mycelium.

  18. Projectile fragmentation in reactions induced by 19F at low energy

    International Nuclear Information System (INIS)

    Pop, A.; Cenja, M.; Duma, M.; Dumitrescu, R.; Isbasescu, A.; Magda, M.T.

    1984-09-01

    Light-particle emission was studied in 19 F + 12 C and 19 F + 27 Al reactions at 72 MeV. The spectral shape shows an important breakup component in the case of 2 H, 3 H and 3 He while in the case of 1 H and 4 He the statistical contribution is predominant. The emission of 6 He, 6 Li, 7 Li and 9 Be was also observed and explained by the projectile breakup mechanism within the Serber model. The experimental isotope yields are in good agreement with the theoretical predictions of the Friedman model. (authors)

  19. Serotypes, antibiotic susceptibilities, and multi-locus sequence type profiles of Streptococcus agalactiae isolates circulating in Beijing, China.

    Science.gov (United States)

    Wang, Ping; Tong, Jing-jing; Ma, Xiu-hua; Song, Feng-li; Fan, Ling; Guo, Cui-mei; Shi, Wei; Yu, Sang-jie; Yao, Kai-hu; Yang, Yong-hong

    2015-01-01

    To investigate the serotypes, antibiotic susceptibilities, and multi-locus sequence type (MLST) profiles of Streptococcus agalactiae (S. agalactiae) in Beijing to provide references for the prevention and treatment of S. agalactiae infections. All isolates were identified using the CAMP test and the latex-agglutination assay and serotyped using a Strep-B-Latex kit, after which they were assessed for antibiotic susceptibility, macrolide-resistance genes, and MLST profiles. In total, 56 S. agalactiae isolates were identified in 863 pregnant women (6.5%). Serotypes Ia, Ib, II, III, and V were identified, among which types III (32.1%), Ia (17.9%), Ib (16.1%), and V (14.3%) were the predominant serotypes. All isolates were susceptible to penicillin and ceftriaxone. The nonsusceptiblity rates measured for erythromycin, clarithromycin, azithromycin, telithromycin, clindamycin, tetracycline, and levofloxacin were 85.7%, 92.9%, 98.2%, 30.4%, 73.2%, 91%, and 39.3%, respectively. We identified 14 sequence types (STs) for the 56 isolates, among which ST19 (30.4%) was predominant. The rate of fluoroquinolone resistance was higher in serotype III than in the other serotypes. Among the 44 erythromycin-resistant isolates, 32 (72.7%) carried ermB. S. agalactiae isolates of the serotypes Ia, Ib, III, and V are common in Beijing. Among the S. agalactiae isolates, the macrolide and clindamycin resistance rates are extremely high. Most of the erythromycin-resistant isolates carry ermB.

  20. Application of NMR Screening Methods with 19F Detection to Fluorinated Compounds Bound to Proteins

    Directory of Open Access Journals (Sweden)

    Kazuo Furihata

    2017-12-01

    Full Text Available The combinational use of one-dimensional (1D NMR-based screening techniques with 1H and 19F detections were applied to a human serum albumin–diflunisal complex. Since most NMR screening methods observe 1H spectra, the overlapped 1H signals were unavailable in the binding epitope mapping. However, the NMR experiments with 19F detection can be used as an effective complementary method. For the purpose of identifying the 1H and 19F binding epitopes of diflunisal, this paper carries out a combinatorial analysis using 1H{1H} and 19F{1H} saturation transfer difference experiments. The differences of the 1H-inversion recovery rates with and without target irradiation are also analyzed for a comprehensive interpretation of binding epitope mapping.

  1. Molecular epidemiology of pneumococcal isolates from children in China

    Directory of Open Access Journals (Sweden)

    Li-Hua Kang

    2016-04-01

    Full Text Available Objectives: To investigate the molecular epidemiology of pneumococcal isolates in Chongqing, China. Methods: In this cross-sectional study, 51 invasive Streptococcus pneumoniae (S. pneumoniae strains were from children with invasive pneumococcal disease (IPD and 32 carriage strains from healthy children from January 2010 to December 2013 at the Children’s Hospital of Chongqing Medical University, Chongqing, China. Multilocus sequence typing was used to identify the sequence types (STs. Capsular serotypes were determined by multiplex polymerase chain reaction. Drug susceptibility and resistance was determined by minimum inhibitory concentrations. Results: In this study, 11 serotypes were identified among the 83 S. pneumoniae clinical isolates tested. Prevalent serotypes were 19A (20.4%, 6A/B (20.4%, 19F (15.7%, 14 (14.5%, and 23F (10.8%. Serotype 19F was the most frequent carriage strain, and serotype 19A was the most frequent invasive strain. The ST983 was the most prevalent ST for carriage strains, and ST320 was the most prevalent ST for invasive strains. For gene analysis, psaA (99.5% and piaA (98.6% were present and much conserved in all pneumococci tested. The cps2A and pcsB genes were more frequent in invasive isolates than carriage strains. Antimicrobial resistance rates of invasive pneumococcal isolates to erythromycin, penicillin, meropenem, cefotaxime, and clindamycin were higher than the carriage isolates from children. Conclusion: Our epidemiological evidence shows that 19A, 6A/B, 19F, 14, and 23F remain the most prevalent serotypes, which can be targeted by PCV13. Genotypes and drug resistance varied between carriage and invasive strains. The PsaA and PiaA may be good protein vaccine candidates.

  2. Serotype distribution of pneumococci isolated from pediatric patients with acute otitis media and invasive infections, and potential coverage of pneumococcal conjugated vaccines Distribución de serotipos de neumococos aislados de pacientes pediátricos con otitis media aguda e infecciones invasivas y su cobertura potencial a través de vacunas conjugadas

    Directory of Open Access Journals (Sweden)

    Vanesa Reijtman

    2013-03-01

    Full Text Available A 16-month prospective, descriptive study was conducted on pneumococcal serotype distribution isolated from children with acute otitis media (AÜM and invasive infections (INV. Eighty-nine children with pneumococcal INV and 324 with a first episode of AOM were included. Bacterial pathogens (N = 326 were isolated from the middle-ear fluid of 250 patients. A total of 30 pneumococcal serotypes were identified. Prevalent serotypes were 14, 19A, 9V, 3, 19F, 6A, 23F, and 18C in AOM and 14, 1, 19A, 5, 12F, 6B, and 18C in INV. Potential coverage with PCV10 vaccine would be 46.5 % and 60.7 % for pneumococci involved in AOM and INV, respectively; it would be 71.7 % and 73 % with PCV13. PCV10, conjugated with a Haemophilus protein, would have an immunologic coverage of 39.9 % for AOM vs. 18.5 % with PCV13. However, differences in the prevention of INV were crucial for the decision to include the 13-valent vaccine in the national calendar for children less than two years old in Argentina.Se realizó un estudio prospectivo descriptivo sobre la distribución de serotipos de neumococos aislados de niños con otitis media aguda (OMA y con infecciones invasivas (INV en un período de 16 meses. Se incluyeron 89 niños con INV neumocócicas y 324 con un primer episodio de OMA. Trescientos cuarenta y seis patógenos se aislaron de las secreciones de oído medio obtenidas de 250 pacientes. Se identificaron 30 serotipos y los más prevalentes fueron el 14, 19A, 9V, 3, 19F, 6A, 23F y 18C en OMA y el 14, 1, 19A, 5, 12F, 6B y 18C en INV. La cobertura potencial con la vacuna PCV10 sería de 46,5 % y 60,7 % para neumococos involucrados en OMA y en INV, respectivamente; con la PCV13, esta sería de 71,7 % y 73 %. La PCV10 conjugada con una proteína de Haemophilus tendría una cobertura inmunológica del 39,9 % para OMA, contra una cobertura del 18,5 % de la PCV13. Sin embargo, las diferencias en la prevención de INV fueron determinantes a la hora de considerar

  3. First evidences for 19F(α, p)22Ne at astrophysical energies

    International Nuclear Information System (INIS)

    D’Agata, G.; Spitaleri, C.; Pizzone, R.G.; Figuera, P.; Guardo, G.L.; Gulino, M.; Indelicato, I.; La Cognata, M.; Lattuada, M.; Sergi, M.L.; Blagus, S.; Mijatović, T.; Milin, M.; Miljanic, D.; Prepolec, L.; Skukan, N.; Grassi, L.; Lamia, L.; Hayakawa, S.; Kshetri, R.

    2016-01-01

    19 F experimental abundances is overestimated in respect to the theoretical one: it is therefore clear that further investigations are needed. We focused on the 19 F(α, p) 22 Ne reaction, representing the main destruction channel in He-rich environments. The lowest energy at which this reaction has been studied with direct methods is E C.M. ≈ 0.91 MeV, while the Gamow region is between 0.39 ÷ 0.8 MeV, far below the Coulomb barrier (3.8 MeV). For this reason, an experiment at Rudjer Boskovic Institute (Zagreb) was performed, applying the Trojan Horse Method. Following this method we selected the quasi-free contribution coming from 6 Li( 19 F,p 22 Ne) 2 H at E beam =6 MeV at kinematically favourable angles, and the cross section at energies 0 < E C.M. < 1.4 MeV was extracted in arbitrary units, covering the astrophysical region of interest. (paper)

  4. Polyguluronate sulfate and its oligosaccharides but not heparin promotes FGF19/FGFR1c signaling

    Science.gov (United States)

    Lan, Ying; Zeng, Xuan; Guo, Zhihua; Zeng, Pengjiao; Hao, Cui; Zhao, Xia; Yu, Guangli; Zhang, Lijuan

    2017-06-01

    Fibroblast growth factor 19(FGF19) functions as a hormone by affecting glucose metabolism. FGF19 improves glucose tolerance when overexpressed in mice with impaired glucose tolerance or diabetes. A functional cellular FGF19 receptor consists of FGF receptor (FGFR) and glycosaminoglycan complexed with either α Klotho or β Klotho. Interestingly, in mice with diet-induced diabetes, a single injection of FGF1 is enough to restore blood sugar levels to a healthy range. FGF1 binds heparin with high affinity whereas FGF19 does not, indicating that polysaccharides other than heparin might enhance FGF19/FGFR signaling. Using a FGFs/FGFR1c signaling-dependent BaF3 cell proliferation assay, we discovered that polyguluronate sulfate (PGS) and its oligosaccharides, PGS12 and PGS25, but not polyguluronate (PG), a natural marine polysaccharide, enhanced FGF19/FGFR1c signaling better than that of heparin based on 3H-thymidine incorporation. Interestingly, PGS6, PGS8, PGS10, PGS12, PGS25, and PGS, but not PG, had comparable FGF1/FGFR1c signal-stimulating activity compared to that of heparin. These results indicated that PGS and its oligosaccharides were excellent FGF1/FGFR1c and FGF19/FGFR1c signaling enhancers at cellular level. Since the inexpensive PGS and PGS oligosaccharides can be absorbed through oral route, these seaweed-derived compounds merit further investigation as novel agents for the treatment of type 2 diabetes through enhancing FGF1/FGFR1c and FGF19/FGFR1c signaling in future.

  5. Preliminary study of the 19F(7Li,7Be)19O reaction at 52 MeV with MAGNEX

    CERN Document Server

    Cavallaro, M; Cappuzzello, F; Carbone, D; Foti, A; Orrigo, S E A; Rodrigues, M R D; Schillaci, M; Borello-Lewin, T; Petrascu, H

    2010-01-01

    The 19F(7Li,7Be)19O charge-exchange reaction at 52 MeV incident energy has been performed at INFN-LNS in Catania using the MAGNEX spectrometer. The use of an algebraic ray-reconstruction technique has allowed to extract the 19O excitation energy spectrum and the experimental angular distributions obtained with a single angular setting of the spectrometer.

  6. Serotype distribution in non-bacteremic pneumococcal pneumonia

    DEFF Research Database (Denmark)

    Benfield, Thomas Lars Vibe; Skovgaard, Marlene; Schønheyder, Henrik Carl

    2013-01-01

    There is limited knowledge of serotypes that cause non-bacteremic pneumococcal pneumonia (NBP). Here we report serotypes, their associated disease potential and coverage of pneumococcal conjugate vaccines (PCV) in adults with NBP and compare these to bacteremic pneumonia (BP).......There is limited knowledge of serotypes that cause non-bacteremic pneumococcal pneumonia (NBP). Here we report serotypes, their associated disease potential and coverage of pneumococcal conjugate vaccines (PCV) in adults with NBP and compare these to bacteremic pneumonia (BP)....

  7. Monitoring 5-fluorouracil in patients undergoing chemotherapy by means of F-19 MR spectroscopy

    International Nuclear Information System (INIS)

    Wolf, W.; Albright, M.J.; Silver, M.S.; Starewicz, P.M.; Weber, H.; Reichardt, U.; Saver, R.

    1986-01-01

    F-19 MR spectroscopy allows direct observation of fluorinated drugs and their metabolites in the human body without background signal from the tissue. In addition, unlike F-18, specific chemical structure information is available in vivo. The behavior of a well-known fluorinated chemotherapeutic drug, 5-fluorouracil (5-FU), and its metabolites was observed noninvasively in patients undergoing cancer chemotherapy. The time course of the drug's metabolism was examined and half-life values of the unmetabolized 5-FU in the liver were calculated from the F-19 peak intensity. Half-life values of the unmetabolized 5-FU in the liver were in the range of 15-30 minutes. Interpatient variations were correlated with the chemotherapy results. F-19 MR spectroscopy is feasible in humans and allows determination of the time course of the metabolism of fluorinated drugs in individual patients

  8. Immunogenicity of a 23-valent pneumococcal polysaccharide vaccine in elderly residents of a long-term care facility

    Directory of Open Access Journals (Sweden)

    M. Teresa Valenzuela B.

    Full Text Available S. pneumoniae is a significant cause of community-acquired pneumonia in the elderly, and accounts for the majority of the pneumonia deaths among the elderly. We conducted this randomized double-blind study to evaluate the immune response to a 23-valent pneumococcal polysaccharide vaccine and the persistence of antibodies two years after the vaccination in an elderly population in Santiago, Chile. A total of 118 elderly nursing home residents received either the pneumococcal or a tetanus control vaccine. Serum samples were taken at enrolment, at two months, and at two years post-vaccination. Pre-vaccination anti-pneumococcal antibody geometric mean concentrations (GMC were similar in both study groups, with increased levels of antibodies found only against serotype 14. The pneumococcal vaccine was highly immunogenic at 2 months, and titers remained high two years after the vaccination for the 10 serotypes studied in this elderly population. The results thus support the benefits of this pneumococcal vaccine in this elderly population who are at increased risk of invasive pneumococcal disease.

  9. Boosting the growth of the probiotic strain Lactobacillus paracasei ssp. paracasei F19.

    Science.gov (United States)

    Brignone, Desideria; Radmann, Pia; Behr, Jürgen; Vogel, Rudi F

    2017-08-01

    Single so-called booster substances were added to the fermentation medium of the probiotic strain Lactobacillus (L.) paracasei ssp. paracasei F19 to enhance its growth. A wide screening was carried out in microtiter plates and a statistical analysis of the growth parameters was performed. CFU counts were used to correlate the increase in OD 590nm with the increase in viable cell number. Sodium ascorbate, sodium pyruvate, manganese sulfate and cysteine had a remarkable boosting effect on the growth of L. paracasei F19. Three of the boosters increased the growth rate of the strain and led to a higher cell density and biomass yield in laboratory conditions. Cysteine significantly shortened the lag phase, therefore reducing the fermentation times. The boosters were tested on four additional Lactobacillus species and their growth boosting activity was retained. To investigate whether the growth boosters could improve the tolerance of L. paracasei F19 to the adverse condition in the GI tract, additional tests were performed. Sodium ascorbate and sodium pyruvate exerted a certain antioxidant effect, as they improved the tolerance of L. paracasei F19 to H 2 O 2 . Sodium ascorbate enhanced the growth of the strain in low pH.

  10. [Nasopharyngeal carriage of pneumococcal serotypes in healthy pre-school aged children after 7-valent pneumococcal vaccine].

    Science.gov (United States)

    García-Vera, César; Ruiz Andrés, María Ángeles; Arana Navarro, Teresa; Moneo Hernández, Isabel; Castillo Laita, José Antonio; Macipe Costa, Rosa; Revillo Pinilla, María José

    2011-06-11

    To determine the characteristics influencing pneumococcal serotype colonization in healthy pre-school aged children, the distribution of serotypes and their antimicrobial susceptibility, after the introduction of pneumococcal 7-valent conjugate vaccine (VNC-7 v). SUJETOS AND METHODS: Nasopharyngeal samples were collected from children under 6 years of age attending well-child examinations in the province of Zaragoza (Spain). Logistic regression was used to study different variables related to the status of the carriers. Of the 371 children studied 30.7% were found to be carriers. With a vaccine coverage rate of 66%, factors related with presence of pneumococcal carriage were found to be the number of siblings (OR 1.44; CI 95% 1.05-1.97 for each sibling), attending a school or child day care centre (OR 3.99; CI 95% 2.00-7.96) and suffering from a minor upper respiratory tract infection (URTI) (OR 1.72; CI 95% 1.02-2.90). Only 8.7% corresponded to VNC-7 v serotypes. The most common non VNC-7 v serotypes isolated were 19A, 6A, 15B, 11, and 15A. Significantly greater resistance was detected among VNC-7 v serotypes. Children in the setting of this study carried pneumococci more commonly when they have siblings, attend school or day care, or suffer from minor URTI. In the VNC-7 v vaccine era, VNC-7 v serotypes have become rare occurrences (8.7%) and emerging serotypes present better susceptibility to antibiotics. Copyright © 2010 Elsevier España, S.L. All rights reserved.

  11. High occurrence and unusual serotype diversity of non-typhoidal Salmonella in non-clinical niches, Angola.

    Science.gov (United States)

    Antunes, P; Campos, J; Mourão, J; Ribeiro, T G; Novais, C; Peixe, L

    2017-04-01

    Non-typhoidal Salmonella is an important burden, particularly in developing countries of the African region. We report for the first time in Angola, a sub-Saharan African country with commercial/travel relationships with Europe, an unexpectedly high occurrence of Salmonella (n = 12/63, 19%) from a high diversity of sources, particularly farm and wild animals. The detection of diverse serotypes (n = 12), involving putative new S. enterica subsp. salamae serotypes, is also of note, reinforcing the need for a comprehensive surveillance in Angola critical to identify animal/food/environmental sources of salmonellosis with impact on animal health, local people, tourists and exported products.

  12. Nuclear quadrupole interaction measurements of 19F* and 22Na* on Graphite

    International Nuclear Information System (INIS)

    Djoko-Surono, Th; Martin, Peter W

    1996-01-01

    Time differential perturbed angular distribution (TDPAD) technique has been used to investigate nuclear quadrupole interactions of 19 F * and 22 Na * in graphite. We concentrated the measurements on pseudo single crystal graphite called Highly Oriented Pyrolytic Graphite for it has an ordered structure in which the c-axes of the microcrystals aligned in a certain direction with the mosaic spread less than 1 o , while the a- and b-axes randomly oriented on a plane perpendicular to the c-axes. Interactions between quadrupole moment of 19 F * and 22 Na * with its surroundings electric field gradient were studied by detecting the γ-rays distribution, W(Θ,t). For 1 9F * we found one static interaction. The corresponding electric field gradient was V zz =3.24(19)x10 22 V/m 2 . In the case of 22 Na * we found no evidence of nuclear quadrupole interaction, however, we were able to conclude that |QV 22 | 19 bV/m 2 . Using theoretical calculation Q=0.06 barn, we find that |V zz | 20 V/m 2 . These results indicate that the value efg depend on two factors, the host crystal and the core electrons. The core electrons contribution to the total efg is considerably large

  13. Incidence and serotype characterisation of Streptococcus agalactiae in a Portuguese hospital.

    Science.gov (United States)

    Pinto, Ana Mafalda; Pereira, Tamegão Aires; Alves, Valquíria; Araújo, António; Lage, Olga Maria

    2018-06-01

    Streptococcus agalactiae, commonly known as group B Streptococcus (GBS), has been recognised as a worldwide causative pathogenic agent of neonatal sepsis, meningitis and pneumonia. To better understand the behaviour of S. agalactiae in pregnant women from a hospital from the North of Portugal, retrospective analyses were performed to describe epidemiological, clinical and microbiological characteristics of the isolates obtained. Based on laboratorial records and the hospital's patient files, a 6-year retrospective study was performed to analyse S. agalactiae isolates from screened pregnant women between 35 and 37 weeks of gestation and hospitalised neonates from pregnant women between 24 and 41 weeks of gestation admitted in Hospital Pedro Hispano. Serotype characterisation was also performed in 67 GBS strains. In 6692 pregnant women between 35 and 37 weeks of gestation screened between 2011 and 2016, a total of 1377 S. agalactiae isolates (21%) were found. A high percentage (40%) of unknown colonisation status among hospitalised neonates from pregnant women between 24 and 41 weeks of gestations was also found. The incidence of neonatal sepsis was 8.7 (95% CI 7.0 to 10.8) cases per 1000 live births. Regarding serotype characterisation, serotype III (22.4%) was the most frequent, followed by serotype Ia (19.4%) and serotypes Ib and V (both with 17.9%). High epidemiological values of GBS colonisation and incidence were found in this study. In Portugal studies on the epidemiology and behaviour of S. agalactiae remain limited, reinforcing the importance and need for S. agalactiae screening across the country. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. Human Parvovirus B19 NS1 Protein Aggravates Liver Injury in NZB/W F1 Mice

    Science.gov (United States)

    Tsai, Chun-Chou; Chiu, Chun-Ching; Hsu, Jeng-Dong; Hsu, Huai-Sheng; Tzang, Bor-Show; Hsu, Tsai-Ching

    2013-01-01

    Human parvovirus B19 (B19) has been associated with a variety of diseases. However, the influence of B19 viral proteins on hepatic injury in SLE is still obscure. To elucidate the effects of B19 viral proteins on livers in SLE, recombinant B19 NS1, VP1u or VP2 proteins were injected subcutaneously into NZB/W F1 mice, respectively. Significant expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected in NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Markedly hepatocyte disarray and lymphocyte infiltration were observed in livers from NZB/WF 1 mice receiving B19 NS1 as compared to those mice receiving PBS. Additionally, significant increases of Tumor Necrosis Factor –α (TNF-α), TNF-α receptor, IκB kinase –α (IKK-α), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor (IκB) and nuclear factor-kappa B (NF-κB) were detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Accordingly, significant increases of matrix metalloproteinase-9 (MMP9) and U-plasminogen activator (uPA) were also detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Contrarily, no significant variation on livers from NZB/W F1 mice receiving B19 VP1u or VP2 was observed as compared to those mice receiving PBS. These findings firstly demonstrated the aggravated effects of B19 NS1 but not VP1u or VP2 protein on hepatic injury and provide a clue in understanding the role of B19 NS1 on hepatic injury in SLE. PMID:23555760

  15. Metabolic 19F MRI an dynamic 18F PET for chemotherapy monitoring in experimental tumors

    International Nuclear Information System (INIS)

    Brix, G.; Haberkorn, U.; Bellemann, M.E.

    1999-01-01

    The efficient clinical use of chemotherapeutic agents requires the assessment of the uptake and metabolism of the drugs in the tumor as well as in the various organs of the body by using noninvasive imaging techniques such as magnetic resonance imaging (MRI) and positron emission tomography (PET). In this overview, we present different metabolic 19 F MRI and dynamic 18 F PET techniques for noninvasive monitoring of fluorine-containing anticancer drugs and evaluate their potentials and limitations within the framework of experimental animal studies. (orig.) [de

  16. Synthesis of Intrinsically Disordered Fluorinated Peptides for Modular Design of High-Signal 19 F MRI Agents.

    Science.gov (United States)

    Kirberger, Steven E; Maltseva, Sofia D; Manulik, Joseph C; Einstein, Samuel A; Weegman, Bradley P; Garwood, Michael; Pomerantz, William C K

    2017-06-01

    19 F MRI is valuable for in vivo imaging due to the only trace amounts of fluorine in biological systems. Because of the low sensitivity of MRI however, designing new fluorochemicals remains a significant challenge for achieving sufficient 19 F signal. Here, we describe a new class of high-signal, water-soluble fluorochemicals as 19 F MRI imaging agents. A polyamide backbone is used for tuning the proteolytic stability to avoid retention within the body, which is a limitation of current state-of-the-art perfluorochemicals. We show that unstructured peptides containing alternating N-ϵ-trifluoroacetyllysine and lysine provide a degenerate 19 F NMR signal. 19 F MRI phantom images provide sufficient contrast at micromolar concentrations, showing promise for eventual clinical applications. Finally, the degenerate high signal characteristics were retained when conjugated to a large protein, indicating potential for in vivo targeting applications, including molecular imaging and cell tracking. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. In-Vivo Detection and Tracking of T Cells in Various Organs in a Melanoma Tumor Model by 19F-Fluorine MRS/MRI.

    Directory of Open Access Journals (Sweden)

    Christine Gonzales

    Full Text Available 19F-MRI and 19F-MRS can identify specific cell types after in-vitro or in-vivo 19F-labeling. Knowledge on the potential to track in-vitro 19F-labeled immune cells in tumor models by 19F-MRI/MRS is scarce.To study 19F-based MR techniques for in-vivo tracking of adoptively transferred immune cells after in-vitro 19F-labeling, i.e. to detect and monitor their migration non-invasively in melanoma-bearing mice.Splenocytes (SP were labeled in-vitro with a perfluorocarbon (PFC and IV-injected into non-tumor bearing mice. In-vitro PFC-labeled ovalbumin (OVA-specific T cells from the T cell receptor-transgenic line OT-1, activated with anti-CD3 and anti-CD28 antibodies (Tact or OVA-peptide pulsed antigen presenting cells (TOVA-act, were injected into B16 OVA melanoma-bearing mice. The distribution of the 19F-labelled donor cells was determined in-vivo by 19F-MRI/MRS. In-vivo 19F-MRI/MRS results were confirmed by ex-vivo 19F-NMR and flow cytometry.SP, Tact, and TOVA-act were successfully PFC-labeled in-vitro yielding 3x1011-1.4x1012 19F-atoms/cell in the 3 groups. Adoptively transferred 19F-labeled SP, TOVA-act, and Tact were detected by coil-localized 19F-MRS in the chest, abdomen, and left flank in most animals (corresponding to lungs, livers, and spleens, respectively, with highest signal-to-noise for SP vs TOVA-act and Tact, p<0.009 for both. SP and Tact were successfully imaged by 19F-MRI (n = 3; liver. These in-vivo data were confirmed by ex-vivo high-resolution 19F-NMR-spectroscopy. By flow cytometric analysis, however, TOVA-act tended to be more abundant versus SP and Tact (liver: p = 0.1313; lungs: p = 0.1073; spleen: p = 0.109. Unlike 19F-MRI/MRS, flow cytometry also identified transferred immune cells (SP, Tact, and TOVA-act in the tumors.SP, Tact, and TOVA-act were successfully PFC-labeled in-vitro and detected in-vivo by non-invasive 19F-MRS/MRI in liver, lung, and spleen. The portion of 19F-labeled T cells in the adoptively transferred cell

  18. Direct Comparison of 19F qNMR and 1H qNMR by Characterizing Atorvastatin Calcium Content

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2016-01-01

    Full Text Available Quantitative nuclear magnetic resonance (qNMR is a powerful tool in measuring drug content because of its high speed, sensitivity, and precision. Most of the reports were based on proton qNMR (1H qNMR and only a few fluorine qNMR (19F qNMR were reported. No research has been conducted to directly compare the advantage and disadvantage between these two methods. In the present study, both 19F and 1H qNMR were performed to characterize the content of atorvastatin calcium with the same internal standard. Linearity, precision, and results from two methods were compared. Results showed that 19F qNMR has similar precision and sensitivity to 1H qNMR. Both methods generate similar results compared to mass balance method. Major advantage from 19F qNMR is that the analyte signal is with less or no interference from impurities. 19F qNMR is an excellent approach to quantify fluorine-containing analytes.

  19. A 19F NMR study of C-I....pi- halogen bonding

    DEFF Research Database (Denmark)

    Hauchecorne, Dieter; vand er Veken, Benjamin J.; Herrebout, Wouter A.

    2011-01-01

    The formation of halogen bonded complexes between toluene-d8 and the perfluoroiodopropanes 1-C3F7I and 2-C3F7I has been investigated using 19F NMR spectroscopy. For both Lewis acids, evidence was found for the formation of a C–I⋯π halogen bonded complex. The complex formed is a 1:1 type. Using sp...... results are supported by ab initio calculations at the B3LYP-PCM/6-311++G(d,p) + LanL2DZ∗ level....

  20. Pneumococcal Serotypes Colonise the Nasopharynx in Children at Different Densities.

    Directory of Open Access Journals (Sweden)

    Fernanda Rodrigues

    Full Text Available Prevalence of pneumococcal serotypes in carriage and disease has been described but absolute serotype colonisation densities have not been reported. 515 paediatric nasal swab DNA extracts were subjected to lytA qPCR and molecular serotyping by microarray. Absolute serotype densities were derived from total pneumococcal density (qPCR cycle threshold and standard curve and relative abundance (microarray and varied widely. Compared to all serotype densities observed, the strongest evidence of differences was seen for serotypes 21 and 35B (higher and 3, 38 and non-typeables (lower (p<0.05 with a similar hierarchy when only a single serotype carriage was assessed. There was no evidence of any overall density differences between children with single or multiple serotypes detected but serotypes with mid-range densities were more prevalent. The hierarchy of distinct pneumococcal serotype carriage densities described here for the first time, may help explain the dynamics of transmission between children.

  1. 19F NMR studies of 5-fluorouracil-substituted Escherichia coli transfer RNAs: solution structure and codon-anticodon interaction

    International Nuclear Information System (INIS)

    Gollnick, P.D.

    1986-01-01

    19 F NMR was used to study E. coli tRNA 1 /sup Val/, tRNA/sub f//sup Met/, and tRNA/sub m//Met/, in which 5-fluorouracil (FUra) has replaced uracil and uracil-derived minor bases. 19 F NMR spectra of these tRNAs resolve resonances from nearly all the incorporated FUra residues. Each of the three tRNAs can be resolved into two isoaccepting species, termed forms A and B, whose 19 F spectra differ in the shift of one 19 F peak from ca. 4.5 ppm in form B, upfield to -15 ppm in form A. Because the two isoacceptors of each tRNA differ only at one position, the peaks at 4.5 ppm in the spectra of (FUra)tRNA 1 /sup Val/ and (FUra)tRNA/sub m//sup Met/; are assigned to FUra 17 and Fura 20 respectively. Bisulfate modification and pH dependence indicate that 19 F signals in the central region of the spectrum of (FUra)tRNA 1 /sup Val/ correspond to fluorouracils in non-base-paired regions. Photoreaction with psoralen indicates upfield 19 F signals arise from residues in helical environments. Removal of magnesium or addition of NaCl produces major, reversible changes in the 19 F spectrum of fluorinated tRNAs. Studies of manganese and spermine binding to (FUra)tRNA 1 /sup Val/ allow localization of several resonances in the 18 F spectrum to regions near putative binding sites for these ions. Binding of the codon G/sub p/U/sub p/A causes an upfield shift of a 19 F resonance at 3.9 ppm in the spectrum of (FUra)tRNA 1 /sup Val/. G/sub p/U/sub p/A/sub p/A, which is complementary to the anticodon and 5'-adjacent FUra 33, shifts an additional 19 F peak at 4.5 ppm. 1 H NMR and RNase H digestion studies show that the oligonucleotides bind to the anticodon

  2. Maternal Colonization With Group B Streptococcus and Serotype Distribution Worldwide: Systematic Review and Meta-analyses.

    Science.gov (United States)

    Russell, Neal J; Seale, Anna C; O'Driscoll, Megan; O'Sullivan, Catherine; Bianchi-Jassir, Fiorella; Gonzalez-Guarin, Juan; Lawn, Joy E; Baker, Carol J; Bartlett, Linda; Cutland, Clare; Gravett, Michael G; Heath, Paul T; Le Doare, Kirsty; Madhi, Shabir A; Rubens, Craig E; Schrag, Stephanie; Sobanjo-Ter Meulen, Ajoke; Vekemans, Johan; Saha, Samir K; Ip, Margaret

    2017-11-06

    Maternal rectovaginal colonization with group B Streptococcus (GBS) is the most common pathway for GBS disease in mother, fetus, and newborn. This article, the second in a series estimating the burden of GBS, aims to determine the prevalence and serotype distribution of GBS colonizing pregnant women worldwide. We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus), organized Chinese language searches, and sought unpublished data from investigator groups. We applied broad inclusion criteria to maximize data inputs, particularly from low- and middle-income contexts, and then applied new meta-analyses to adjust for studies with less-sensitive sampling and laboratory techniques. We undertook meta-analyses to derive pooled estimates of maternal GBS colonization prevalence at national and regional levels. The dataset regarding colonization included 390 articles, 85 countries, and a total of 299924 pregnant women. Our adjusted estimate for maternal GBS colonization worldwide was 18% (95% confidence interval [CI], 17%-19%), with regional variation (11%-35%), and lower prevalence in Southern Asia (12.5% [95% CI, 10%-15%]) and Eastern Asia (11% [95% CI, 10%-12%]). Bacterial serotypes I-V account for 98% of identified colonizing GBS isolates worldwide. Serotype III, associated with invasive disease, accounts for 25% (95% CI, 23%-28%), but is less frequent in some South American and Asian countries. Serotypes VI-IX are more common in Asia. GBS colonizes pregnant women worldwide, but prevalence and serotype distribution vary, even after adjusting for laboratory methods. Lower GBS maternal colonization prevalence, with less serotype III, may help to explain lower GBS disease incidence in regions such as Asia. High prevalence worldwide, and more serotype data, are relevant to prevention efforts. © The Author 2017. Published by

  3. Detection of psychoactive drugs using 19F MR spectroscopy

    International Nuclear Information System (INIS)

    Bartels, M.; Albert, K.

    1995-01-01

    In vivo 19 F resonance spectroscopy measurements of tri fluorinated neuroleptics (flu phenazine and tri fluoperazine) and later tri fluorinated antidepressants (fluoxetine and fluvoxamine) began with animal experiments in 1983. Using rats which have been treated with high oral doses of flu phenazine over a period of three weeks at the beginning of these experiments the measurement time was very long (up to 10 h). The application of better techniques using surface coils led to a marked improvement of the signal noise ratio and measurement times in animal experiments could be reduced to minutes. These results encouraged us and other groups to perform experiments in humans to detect and try to estimate brain levels of tri fluorinated neuroleptics and antidepressants. The present data of several research groups demonstrate that 19 F MR spectroscopy has the potential of becoming a valuable tool for monitoring drug levels at the site of action. The extension of the animal studies to humans might facilitate a better treatment of schizophrenic and depressive patients. (author)

  4. Three enzymatically active neurotoxins of Clostridium botulinum strain Af84: BoNT/A2, /F4, and /F5.

    Science.gov (United States)

    Kalb, Suzanne R; Baudys, Jakub; Smith, Theresa J; Smith, Leonard A; Barr, John R

    2014-04-01

    Botulinum neurotoxins (BoNTs) are produced by various species of clostridia and are potent neurotoxins which cause the disease botulism, by cleaving proteins needed for successful nerve transmission. There are currently seven confirmed serotypes of BoNTs, labeled A-G, and toxin-producing clostridia typically only produce one serotype of BoNT. There are a few strains (bivalent strains) which are known to produce more than one serotype of BoNT, producing either both BoNT/A and /B, BoNT/A and /F, or BoNT/B and /F, designated as Ab, Ba, Af, or Bf. Recently, it was reported that Clostridium botulinum strain Af84 has three neurotoxin gene clusters: bont/A2, bont/F4, and bont/F5. This was the first report of a clostridial organism containing more than two neurotoxin gene clusters. Using a mass spectrometry based proteomics approach, we report here that all three neurotoxins, BoNT/A2, /F4, and /F5, are produced by C. botulinum Af84. Label free MS(E) quantification of the three toxins indicated that toxin composition is 88% BoNT/A2, 1% BoNT/F4, and 11% BoNT/F5. The enzymatic activity of all three neurotoxins was assessed by examining the enzymatic activity of the neurotoxins upon peptide substrates, which mimic the toxins' natural targets, and monitoring cleavage of the substrates by mass spectrometry. We determined that all three neurotoxins are enzymatically active. This is the first report of three enzymatically active neurotoxins produced in a single strain of Clostridium botulinum.

  5. The application of in vivo 19F-NMR to biological systems

    International Nuclear Information System (INIS)

    Higuchi, Toshihiro

    1989-01-01

    The potential application of in vivo F-19 NMR spectroscopy in the clinical setting was evaluated with Wistar rats and Mongolian gerbils. Halothane was inhalated and perfluorochemical (FC-43) was administered to rats. Fluorine-19 NMR spectra from halothane were obtained in both the brain and liver 5 min after inhalation, and the signal intensity increased with time. Although the intensity decreased immediately after cessation of inhalation, it was detectable even at 24 hr. The signal intensity from the liver was twice that from the brain. As for FC-43, the signal intensity was 8 times larger in the liver than the brain. At 24 hr after administration of FC-43, FC-43 spectra from the liver were increased, while those from the brain were decreased. An experiment with gerbils with experimentally induced cerebral ischemia revealed a definitive correlation between brain energy metabolism disorder as measured by p-31 NMR spectra and a decreased signal intensity for FC-43 as measured by F-19 NMR spectra. FC-43 signal intesntity obtained from the ischemic brain was reduced to 60-64% of the level of the normal brain. A linear correlation between 1/T1 and PO2 was reconfirmed by in vitro studies of T1 measurements of FC-43 mixed in human blood. In vivo F-19 NMR spectroscopy has potential for non-invasive evaluation not only of pharmacokinetics of administered fluoric compounds, but also of cerebral circulation or cerebral blood volume and tissue PO2. (Namekawa, K)

  6. Characterization of Co-Cultivation of Cyanobacteria on Growth, Productions of Polysaccharides and Extracellular Proteins, Nitrogenase Activity, and Photosynthetic Activity.

    Science.gov (United States)

    Xue, Chuizhao; Wang, Libo; Wu, Tong; Zhang, Shiping; Tang, Tao; Wang, Liang; Zhao, Quanyu; Sun, Yuhan

    2017-01-01

    Cyanobacteria as biofertilizers are benefit to reduce the use of chemical fertilizers and reestablish the ecological system in soil. In general, several strains of cyanobacteria were involved in the biofertilizers. The co-cultivation of cyanobacteria were characterized on growth profile, production of polysaccharides and extracellular proteins, nitrogenase activity, and photosynthetic activity for three selected N 2 -fixing cyanobacteria, Anabaena cylindrica (B1611 and F243) and Nostoc sp. (F280). After eight-day culture, the highest dry weights were obtained in F280 pure culture and co-cultivation of B1611 and F280. Higher production of extracellular proteins and cell-bonding polysaccharides (CPS) were observed in co-cultivations compared with pure culture. The highest released polysaccharides (RPS) contents were obtained in pure culture of F280 and co-cultivation of F280 and F243. Galactose and glucose were major components of CPS and RPS in all samples. Trehalose was a specific component of RPS in F280 pure culture. Based on the monosaccharide contents of CPS and RPS, F280 was the dominant species in the related treatments of co-cultivation. The nitrogenase activities in all treatments exhibited a sharp rise at the late stage while a significant decrease existed when three cyanobacteria strains were mixed. Photosynthetic activities for all treatments were determined with rapid light curve, and the related parameters were estimated.

  7. Highly efficient F-19 heteronuclear decoupling in solid-state NMR spectroscopy using supercycled refocused-CW irradiation

    DEFF Research Database (Denmark)

    Equbal, Asif; Basse, Kristoffer; Nielsen, Niels Christian

    2016-01-01

    We present heteronuclear F-19 refocused CW (rCW) decoupling pulse sequences for solid-state magic-angle- spinning NMR applications. The decoupling sequences have been designed specifically to ensure suppression of the pertinent C-13-F-19 dipolar coupling interactions while simultaneously suppress...

  8. Electronic stopping powers for fluorine ions in 19F+-implanted AgGaS2 crystal

    International Nuclear Information System (INIS)

    Liu Xiangdong; Xia Yueyuan; Lu Qingming; Li Feng; Huang Boda

    2004-01-01

    Electronic stopping powers for 80-350 keV 19 F ions in AgGaS 2 were obtained by range measurement. Depth profiles of 19 F in AgGaS 2 were measured by using the 19 F(p,αγ) 16 O resonant nuclear reaction at E R =872.1 keV. A proper convolution calculation method was used to extract the true distribution of fluorine from the experimental excitation yield curves. The electronic stopping powers were derived through fitting the projected range distributions, simulated by using the TRIM/XLL code, to the experimentally measured range distributions. The electronic stopping cross sections were compared with those obtained from Monte Carlo simulation codes

  9. Anti-Inflammatory Activity of Polysaccharide Fraction of Curcuma longa Extract (NR-INF-02).

    Science.gov (United States)

    Illuri, Ramanaiah; Bethapudi, Bharathi; Anandakumar, Senthilkumar; Murugan, Sasikumar; Joseph, Joshua A; Mundkinajeddu, Deepak; Agarwal, Amit; Chandrasekaran, C V

    2015-01-01

    The aim of the study was to investigate the safety and anti-inflammatory effects of polysaccharide fraction (F1) of Curcuma longa extract (NR-INF-02) in classical rodent models of inflammation. F1 was evaluated for its acute oral toxicity and found to be safe upto 5000 mg/kg body weight in rats. The anti-inflammatory activity of F1 was evaluated in acute (carrageenan - induced paw edema; xylene - induced ear edema) and chronic (cotton pellet - induced granuloma) models of inflammation. The results of the study demonstrated that F1 significantly (p ≤ 0.05) inhibited carrageenan-induced paw edema at 1 h and 3 h at doses of 11.25, 22.5 and 45 mg/kg body weight in rats. Also, F1 at doses of 15.75, 31.5 and 63 mg/kg significantly inhibited the xylene induced ear edema in mice. In a chronic model, F1 at 11.25, 22.5 and 45 mg/kg doses produced significant reduction of wet and dry weights of cotton pellets in rats. Overall results indicated that F1 of NR-INF-02 significantly attenuated acute and chronic inflammation in rodent models. This study emphasizes on the importance of Curcuma longa polysaccharide's role in acute and chronic inflammation.

  10. Exacerbating effects of human parvovirus B19 NS1 on liver fibrosis in NZB/W F1 mice.

    Directory of Open Access Journals (Sweden)

    Tsai-Ching Hsu

    Full Text Available Systemic lupus erythematosus (SLE is an autoimmune disorder with unknown etiology that impacts various organs including liver. Recently, human parvovirus B19 (B19 is recognized to exacerbate SLE. However, the effects of B19 on liver in SLE are still unclear. Herein we aimed to investigate the effects of B19 on liver in NZB/W F1 mice by injecting subcutaneously with PBS, recombinant B19 NS1, VP1u or VP2, respectively. Our experimental results revealed that B19 NS1 protein significantly enhanced the TGF-β/Smad fibrotic signaling by increasing the expressions of TGF-β, Smad2/3, phosphorylated Smad2/3, Smad4 and Sp1. The consequent fibrosis-related proteins, PAI-1 and α-SMA, were also significantly induced in livers of NZB/W F1 mice receiving B19 NS1 protein. Accordingly, markedly increased collagen deposition was also observed in livers of NZB/W F1 mice receiving B19 NS1 protein. However, no significant difference was observed in livers of NZB/W F1 mice receiving B19 VP1u or VP2 as compared to the controls. These findings indicate that B19 NS1 plays a crucial role in exacerbating liver fibrosis in NZB/W F1 mice through enhancing the TGF-â/Smad fibrotic signaling.

  11. Exacerbating Effects of Human Parvovirus B19 NS1 on Liver Fibrosis in NZB/W F1 Mice

    Science.gov (United States)

    Hsu, Tsai-Ching; Tsai, Chun-Chou; Chiu, Chun-Ching; Hsu, Jeng-Dong; Tzang, Bor-Show

    2013-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disorder with unknown etiology that impacts various organs including liver. Recently, human parvovirus B19 (B19) is recognized to exacerbate SLE. However, the effects of B19 on liver in SLE are still unclear. Herein we aimed to investigate the effects of B19 on liver in NZB/W F1 mice by injecting subcutaneously with PBS, recombinant B19 NS1, VP1u or VP2, respectively. Our experimental results revealed that B19 NS1 protein significantly enhanced the TGF-β/Smad fibrotic signaling by increasing the expressions of TGF-β, Smad2/3, phosphorylated Smad2/3, Smad4 and Sp1. The consequent fibrosis-related proteins, PAI-1 and α-SMA, were also significantly induced in livers of NZB/W F1 mice receiving B19 NS1 protein. Accordingly, markedly increased collagen deposition was also observed in livers of NZB/W F1 mice receiving B19 NS1 protein. However, no significant difference was observed in livers of NZB/W F1 mice receiving B19 VP1u or VP2 as compared to the controls. These findings indicate that B19 NS1 plays a crucial role in exacerbating liver fibrosis in NZB/W F1 mice through enhancing the TGF-â/Smad fibrotic signaling. PMID:23840852

  12. Transplacental Transmission of Bluetongue Virus Serotype 1 and Serotype 8 in Sheep: Virological and Pathological Findings

    NARCIS (Netherlands)

    Sluijs, van der M.T.W.; Schroer-Joosten, D.P.H.; Fid-Fourkour, A.; Vrijenhoek, M.P.; Debyser, I.; Moulin, V.; Moormann, R.J.M.; Smit, de A.J.

    2013-01-01

    The Bluetongue virus serotype 8 (BTV-8) strain, which emerged in Europe in 2006, had an unusually high ability to cause foetal infection in pregnant ruminants. Other serotypes of BTV had already been present in Europe for more than a decade, but transplacental transmission of these strains had never

  13. 19F-nuclear magnetic resonance spectroscopy as a tool to ...

    African Journals Online (AJOL)

    19F-nuclear magnetic resonance spectroscopy as a tool to investigate host-guest complexation of some antidepressant drugs with natural and modified cyclodextrins. Leila Shafiee Dastjerdi1* and Mojtaba Shamsipur2. 1Faculty of Science, Roudehen Branch, Islamic Azad University, Tehran, 2Department of Chemistry, ...

  14. Electronic stopping powers for fluorine ions in {sup 19}F{sup +}-implanted silver gallium diselenide

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xiangdong E-mail: xdliu@sdu.edu.cn; Xia Yueyuan; Li Feng; Lu Qingming; Huang Boda

    2004-08-01

    Electronic stopping powers for 80-350 keV {sup 19}F ions in AgGaSe{sub 2} were obtained by range measurement. Depth profiles of {sup 19}F in AgGaSe{sub 2} were measured by using the {sup 19}F(p,{alpha}{gamma}){sup 16}O resonant nuclear reaction at E{sub R}=872.1 keV. A proper convolution calculation method was used to extract the true distribution of fluorine from the experimental excitation yield curves. The electronic stopping powers were derived through fitting the projected range distributions, simulated by using the TRIM/XLL code, to the experimentally measured range distributions. The electronic stopping cross-sections were compared with those obtained from Monte Carlo simulation codes.

  15. Polysaccharide-producing microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Braud, J.P.; Chaumont, D.; Gudin, C.; Thepenier, C.; Chassin, P.; Lemaire, C.

    1982-11-01

    The production of extracellular polysaccharides is studied with Nostoc sp (cyanophycus), Porphiridium cruentum, Rhodosorus marinus, Rhodella maculata (rhodophyci) and Chlamydomonas mexicana (chlorophycus). The polysaccharides produced are separated by centrifugation of the culture then precipitation with alcohol. Their chemical structure was studied by infrared spectrometry and acid hydrolysis. By their rheological properties and especially their insensitivity to temperatrure and pH variations the polysaccharides produced by Porphryridium cruentum and Rhodella maculata appear as suitable candidates for industrial applications.

  16. Immunochemical studies and genetic background of two Neisseria meningitidis isolates expressing unusual capsule polysaccharide antigens with specificities of both serogroup Y and W135.

    Science.gov (United States)

    Tsang, Raymond S W; Tsai, Chao Ming; Henderson, Averil M; Tyler, Shaun; Law, Dennis K S; Zollinger, Wendell; Jamieson, Frances

    2008-03-01

    We described 2 unusual Neisseria meningitidis strains isolated from epidemiologically unrelated invasive meningococcal disease cases in Ontario, Canada. Both isolates have features typical of serogroup Y N. meningitidis: are of serotype 2c, are of the multi-locus sequence types typical of the serogroup Y strains in Canada, and are genotyped as serogroup Y based on a previously described PCR-ELISA method that detects the serogroup-Y-specific siaD gene. However, both strains were poly-agglutinable in both anti-Y and anti-W135 antisera. Further studies on 1 of these 2 isolates showed the presence of glucose and galactose as well as sialic acids in its purified capsular polysaccharide, suggesting the presence of both serogroup Y and serogroup W135 polysaccharides. Rabbit antisera produced to this strain contained antibodies to both purified serogroup Y and serogroup W135 capsular polysaccharides. Absorption experiments with either serogroup Y or serogroup W135 bacteria confirmed the presence of antibodies to these 2 different polysaccharides. DNA sequencing of the cps operon from both isolates revealed a siaD gene with 99.7% homology to the published siaD sequence from a serogroup Y strain but with 3 point mutations that all resulted in amino acid changes. How these strains may affect results of routine surveillance, PCR diagnosis, and immuno-protection by vaccination are discussed.

  17. Identification and differentiation of the twenty six bluetongue virus serotypes by RT-PCR amplification of the serotype-specific genome segment 2.

    Directory of Open Access Journals (Sweden)

    Narender S Maan

    Full Text Available Bluetongue (BT is an arthropod-borne viral disease, which primarily affects ruminants in tropical and temperate regions of the world. Twenty six bluetongue virus (BTV serotypes have been recognised worldwide, including nine from Europe and fifteen in the United States. Identification of BTV serotype is important for vaccination programmes and for BTV epidemiology studies. Traditional typing methods (virus isolation and serum or virus neutralisation tests (SNT or VNT are slow (taking weeks, depend on availability of reference virus-strains or antisera and can be inconclusive. Nucleotide sequence analyses and phylogenetic comparisons of genome segment 2 (Seg-2 encoding BTV outer-capsid protein VP2 (the primary determinant of virus serotype were completed for reference strains of BTV-1 to 26, as well as multiple additional isolates from different geographic and temporal origins. The resulting Seg-2 database has been used to develop rapid (within 24 h and reliable RT-PCR-based typing assays for each BTV type. Multiple primer-pairs (at least three designed for each serotype were widely tested, providing an initial identification of serotype by amplification of a cDNA product of the expected size. Serotype was confirmed by sequencing of the cDNA amplicons and phylogenetic comparisons to previously characterised reference strains. The results from RT-PCR and sequencing were in perfect agreement with VNT for reference strains of all 26 BTV serotypes, as well as the field isolates tested. The serotype-specific primers showed no cross-amplification with reference strains of the remaining 25 serotypes, or multiple other isolates of the more closely related heterologous BTV types. The primers and RT-PCR assays developed in this study provide a rapid, sensitive and reliable method for the identification and differentiation of the twenty-six BTV serotypes, and will be updated periodically to maintain their relevance to current BTV distribution and

  18. 19F-labeling of the adenine H2-site to study large RNAs by NMR spectroscopy

    International Nuclear Information System (INIS)

    Sochor, F.; Silvers, R.; Müller, D.; Richter, C.; Fürtig, B.; Schwalbe, H.

    2016-01-01

    In comparison to proteins and protein complexes, the size of RNA amenable to NMR studies is limited despite the development of new isotopic labeling strategies including deuteration and ligation of differentially labeled RNAs. Due to the restricted chemical shift dispersion in only four different nucleotides spectral resolution remains limited in larger RNAs. Labeling RNAs with the NMR-active nucleus 19 F has previously been introduced for small RNAs up to 40 nucleotides (nt). In the presented work, we study the natural occurring RNA aptamer domain of the guanine-sensing riboswitch comprising 73 nucleotides from Bacillus subtilis. The work includes protocols for improved in vitro transcription of 2-fluoroadenosine-5′-triphosphat (2F-ATP) using the mutant P266L of the T7 RNA polymerase. Our NMR analysis shows that the secondary and tertiary structure of the riboswitch is fully maintained and that the specific binding of the cognate ligand hypoxanthine is not impaired by the introduction of the 19 F isotope. The thermal stability of the 19 F-labeled riboswitch is not altered compared to the unmodified sequence, but local base pair stabilities, as measured by hydrogen exchange experiments, are modulated. The characteristic change in the chemical shift of the imino resonances detected in a 1 H, 15 N-HSQC allow the identification of Watson–Crick base paired uridine signals and the 19 F resonances can be used as reporters for tertiary and secondary structure transitions, confirming the potential of 19 F-labeling even for sizeable RNAs in the range of 70 nucleotides

  19. In vivo imaging of stepwise vessel occlusion in cerebral photothrombosis of mice by 19F MRI.

    Directory of Open Access Journals (Sweden)

    Gesa Weise

    Full Text Available (19F magnetic resonance imaging (MRI was recently introduced as a promising technique for in vivo cell tracking. In the present study we compared (19F MRI with iron-enhanced MRI in mice with photothrombosis (PT at 7 Tesla. PT represents a model of focal cerebral ischemia exhibiting acute vessel occlusion and delayed neuroinflammation.Perfluorocarbons (PFC or superparamagnetic iron oxide particles (SPIO were injected intravenously at different time points after photothrombotic infarction. While administration of PFC directly after PT induction led to a strong (19F signal throughout the entire lesion, two hours delayed application resulted in a rim-like (19F signal at the outer edge of the lesion. These findings closely resembled the distribution of signal loss on T2-weighted MRI seen after SPIO injection reflecting intravascular accumulation of iron particles trapped in vessel thrombi as confirmed histologically. By sequential administration of two chemically shifted PFC compounds 0 and 2 hours after illumination the different spatial distribution of the (19F markers (infarct core/rim could be visualized in the same animal. When PFC were applied at day 6 the fluorine marker was only detected after long acquisition times ex vivo. SPIO-enhanced MRI showed slight signal loss in vivo which was much more prominent ex vivo indicative for neuroinflammation at this late lesion stage.Our study shows that vessel occlusion can be followed in vivo by (19F and SPIO-enhanced high-field MRI while in vivo imaging of neuroinflammation remains challenging. The timing of contrast agent application was the major determinant of the underlying processes depicted by both imaging techniques. Importantly, sequential application of different PFC compounds allowed depiction of ongoing vessel occlusion from the core to the margin of the ischemic lesions in a single MRI measurement.

  20. The combined application of 1H MRI and 19F MRS to the study of cerebroprotection

    International Nuclear Information System (INIS)

    Haga, K.K.

    2000-01-01

    The research presented in this thesis focuses on the application of 1 H and 19 F nuclear magnetic resonance techniques to the evaluation of the neuroprotective and pharmacokinetic properties of a novel, nitric oxide synthase inhibitor in a rat model of stroke. Although there is a growing body of research on the application of 19 F magnetic resonance spectroscopy techniques to the study of psychotropic agents, this is the first attempt to apply these methods to the evaluation of an agent being developed for cerebroprotection. TRIM, 1-(2-trifluoromethylphenyl) imidazole, is a selective inhibitor of the neuronal form of nitric oxide synthase in the rat and mouse brain. The first portion of this thesis demonstrates TRIM's neuroprotective properties when administered post-occlusion in the middle cerebral artery occlusion model of focal cerebral ischaemia. In addition, these neuroprotective effects may be eliminated by the co-administration of L-arginine, a nitric oxide precursor, indicating a role for neuronal nitric oxide synthase in ischaemic damage. 1 H magnetic resonance imaging at 24 hours post-occlusion indicates a 40% reduction in lesion volume following TRIM administration as compared to the saline control group. The second part of this thesis pertains to the development and application of 19 F MRS methods, in vivo and in vitro, to enable the investigator to monitor and quantify TRIM in the rat CNS pre and post-occlusion. In this section, 19 F MRS studies were conducted to measure the in vivo T 1 and T 2 relaxation parameters and subsequently, the concentration of TRIM achieved in the rat CNS over an 8 hour measuring period. From this data, the in vivo pharmacokinetics of TRIM were evaluated and applied to the neuroprotective strategy in cerebral ischaemia. In vitro measurements of TRIM concentrations in the rat CNS were compared to the in vivo concentration calculations to evaluate the reliability of TRIM quantification using the combined coils system. Finally

  1. Biochemical And Genetic Modification Of Polysaccharides

    Science.gov (United States)

    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.

  2. Group B streptococcal carriage, serotype distribution and antibiotic susceptibilities in pregnant women at the time of delivery in a refugee population on the Thai-Myanmar border

    Directory of Open Access Journals (Sweden)

    Turner Claudia

    2012-02-01

    Full Text Available Abstract Background Group B Streptococcus (GBS is the leading cause of neonatal sepsis in the developed world. Little is known about its epidemiology in the developing world, where the majority of deaths from neonatal infections occur. Maternal carriage of GBS is a prerequisite for the development of early onset GBS neonatal sepsis but there is a paucity of carriage data published from the developing world, in particular South East Asia. Methods We undertook a cross sectional study over a 13 month period in a remote South East Asian setting on the Thai-Myanmar border. During labour, 549 mothers had a combined vaginal rectal swab taken for GBS culture. All swabs underwent both conventional culture as well as PCR for GBS detection. Cultured GBS isolates were serotyped by latex agglutination, those that were negative or had a weak positive reaction and those that were PCR positive but culture negative were additionally tested using multiplex PCR based on the detection of GBS capsular polysaccharide genes. Results The GBS carriage rate was 12.0% (95% CI: 9.4-15.0, with 8.6% positive by both culture and PCR and an additional 3.5% positive by PCR alone. Serotypes, Ia, Ib, II, III, IV, V, VI and VII were identified, with II the predominant serotype. All GBS isolates were susceptible to penicillin, ceftriaxone and vancomycin and 43/47 (91.5% were susceptible to erythromycin and clindamycin. Conclusions GBS carriage is not uncommon in pregnant women living on the Thai-Myanmar border with a large range of serotypes represented.

  3. The metabolism of 2-trifluormethylaniline and its acetanilide in the rat by 19F NMR monitored enzyme hydrolysis and 1H/19F HPLC-NMR spectroscopy.

    Science.gov (United States)

    Tugnait, M; Lenz, E M; Hofmann, M; Spraul, M; Wilson, I D; Lindon, J C; Nicholson, J K

    2003-01-01

    The urinary excretion profile and identity of the metabolites of 2-trifluoromethyl aniline (2-TFMA) and 2-trifluoromethyl acetanilide (2-TFMAc), following i.p. administration to the rat at 50 mg kg(-1), were determined using a combination of 19F NMR monitored enzyme hydrolysis, SPEC-MS and 19F/1H HPLC-NMR. A total recovery of approximately 96.4% of the dose was excreted into the urine as seven metabolites. The major routes of metabolism were N-conjugation (glucuronidation), and ring-hydroxylation followed by sulphation (and to a lesser extent glucuronidation). The major metabolites excreted into the urine for both compounds were a labile N-conjugated metabolite (a postulated N-glucuronide) and a sulphated ring-hydroxylated metabolite (a postulated 4-amino-5-trifluoromethylphenyl sulphate) following dosing of 2-TFMA. These accounted for approximately 53.0 and 31.5% of the dose, respectively. This study identifies problems on sample component instability in the preparation and analysis procedures.

  4. Anti-biofilm activity: a function of Klebsiella pneumoniae capsular polysaccharide.

    Directory of Open Access Journals (Sweden)

    Marina Dos Santos Goncalves

    Full Text Available Competition and cooperation phenomena occur within highly interactive biofilm communities and several non-biocides molecules produced by microorganisms have been described as impairing biofilm formation. In this study, we investigated the anti-biofilm capacities of an ubiquitous and biofilm producing bacterium, Klebsiella pneumoniae. Cell-free supernatant from K. pneumoniae planktonic cultures showed anti-biofilm effects on most Gram positive bacteria tested but also encompassed some Gram negative bacilli. The anti-biofilm non-bactericidal activity was further investigated on Staphylococcus epidermidis, by determining the biofilm biomass, microscopic observations and agglutination measurement through a magnetic bead-mediated agglutination test. Cell-free extracts from K. pneumoniae biofilm (supernatant and acellular matrix also showed an influence, although to a lesser extend. Chemical analyses indicated that the active molecule was a high molecular weight polysaccharide composed of five monosaccharides: galactose, glucose, rhamnose, glucuronic acid and glucosamine and the main following sugar linkage residues [→ 2-α-L-Rhap-(1 →]; [→ 4-α-L-Rhap-(1 →]; [α-D-Galp-(1 →]; [→ 2,3-α-D-Galp-(1 →]; [→ 3-β-D-Galp-(1 →] and, [→ 4-β-D-GlcAp-(1 →]. Characterization of this molecule indicated that this component was more likely capsular polysaccharide (CPS and precoating of abiotic surfaces with CPS extracts from different serotypes impaired the bacteria-surface interactions. Thus the CPS of Klebsiella would exhibit a pleiotropic activity during biofilm formation, both stimulating the initial adhesion and maturation steps as previously described, but also repelling potential competitors.

  5. Development and characterization of serotype-specific monoclonal antibodies against the dengue virus-4 (DENV-4) non-structural protein (NS1).

    Science.gov (United States)

    Gelanew, Tesfaye; Hunsperger, Elizabeth

    2018-02-06

    Dengue, caused by one of the four serologically distinct dengue viruses (DENV-1 to - 4), is a mosquito-borne disease of serious global health significance. Reliable and cost-effective diagnostic tests, along with effective vaccines and vector-control strategies, are highly required to reduce dengue morbidity and mortality. Evaluation studies revealed that many commercially available NS1 antigen (Ag) tests have limited sensitivity to DENV-4 serotype compared to the other three serotypes. These studies indicated the need for development of new NS1 Ag detection test with improved sensitivity to DENV-4. An NS1 capture enzyme linked immunoassay (ELISA) specific to DENV-4 may improve the detection of DENV-4 cases worldwide. In addition, a serotype-specific NS1 Ag test identifies both DENV and the infecting serotype. In this study, we used a small-ubiquitin-like modifier (SUMO*) cloning vector to express a SUMO*-DENV-4 rNS1 fusion protein to develop NS1 DENV-4 specific monoclonal antibodies (MAbs). These newly developed MAbs were then optimized for use in an anti-NS1 DENV-4 capture ELISA. The serotype specificity and sensitivity of this ELISA was evaluated using (i) supernatants from DENV (1-4)-infected Vero cell cultures, (ii) rNS1s from all the four DENV (1-4) and, (iii) rNS1s of related flaviviruses (yellow fever virus; YFV and West Nile virus; WNV). From the evaluation studies of the newly developed MAbs, we identified three DENV-4 specific anti-NS1 MAbs: 3H7A9, 8A6F2 and 6D4B10. Two of these MAbs were optimal for use in a DENV-4 serotype-specific NS1 capture ELISA: MAb 8A6F2 as the capture antibody and 6D4B10 as a detection antibody. This ELISA was sensitive and specific to DENV-4 with no cross-reactivity to other three DENV (1-3) serotypes and other heterologous flaviviruses. Taken together these data indicated that our MAbs are useful reagents for the development of DENV-4 immunodiagnostic tests.

  6. Cell Labeling for 19F MRI: New and Improved Approach to Perfluorocarbon Nanoemulsion Design

    Directory of Open Access Journals (Sweden)

    Jonathan Williams

    2013-09-01

    Full Text Available This report describes novel perfluorocarbon (PFC nanoemulsions designed to improve ex vivo cell labeling for 19F magnetic resonance imaging (MRI. 19F MRI is a powerful non-invasive technique for monitoring cells of the immune system in vivo, where cells are labeled ex vivo with PFC nanoemulsions in cell culture. The quality of 19F MRI is directly affected by the quality of ex vivo PFC cell labeling. When co-cultured with cells for longer periods of time, nanoemulsions tend to settle due to high specific weight of PFC oils (1.5–2.0 g/mL. This in turn can decrease efficacy of excess nanoemulsion removal and reliability of the cell labeling in vitro. To solve this problem, novel PFC nanoemulsions are reported which demonstrate lack of sedimentation and high stability under cell labeling conditions. They are monodisperse, have small droplet size (~130 nm and low polydispersity (<0.15, show a single peak in the 19F nuclear magnetic resonance spectrum at −71.4 ppm and possess high fluorine content. The droplet size and polydispersity remained unchanged after 160 days of follow up at three temperatures (4, 25 and 37 °C. Further, stressors such as elevated temperature in the presence of cells, and centrifugation, did not affect the nanoemulsion droplet size and polydispersity. Detailed synthetic methodology and in vitro testing for these new PFC nanoemulsions is presented.

  7. F-19 MR imaging in vivo with FTPA

    International Nuclear Information System (INIS)

    Iriguchi, N.; Miyazaki, T.; Hasegawa, J.; Yamamoto, T.; Yamai, S.; Veshima, Y.; Iwasaki, A.; Toyoshima, H.; Maki, T.

    1986-01-01

    Perfluorotripropylamine (FTPA), together with perfluorodecalin (FDC), makes a blood substitute which has been known to be clinically safe for certain applications. A 1-m-bore, 2-T system (Asahi Mark-J Super 200) was used to image a young rabbit. After intravenous administration of FTPA emulsion, F-19 imaging was carried out. One hour after FTPA administration, a faint but certain image was obtained. Twenty-four hours after the administration of FTPA. the liver, spleen, and bone marrow were clearly recognized. Each image was obtained in 2 minutes

  8. Nasopharyngeal carriage, antibiogram & serotype distribution of Streptococcus pneumoniae among healthy under five children

    Directory of Open Access Journals (Sweden)

    K.L. Ravi Kumar

    2014-01-01

    Full Text Available Background & objectives: Information related to nasopharyngeal carriage of Streptococcus pneumoniae among healthy children is scanty in India. This prospective study was undertaken to determine the presence of asymptomatic nasopharyngeal colonization, assess serogroups/types (SGT and drug resistance of S. pneumoniae in children below five years of age. Methods: A total of 109 male and 81 female children in the age group of three months to five years belonging to different socio-economic classes were enrolled. They were recruited across all age groups from those attending paediatric OPD of a tertiary care and research centre for immunization program. Fifty three isolates identified as pneumococci were tested for their antimicrobial susceptibility pattern by Kirby-Bauer′s disc diffusion and E-Test methods. Serotyping was performed by detection of the quelling reaction with specific antiserum. Result: The pneumococcal carriage rate in the study population was 27.9 per cent. The isolation rate was associated with age being higher (49.2% in smaller children (3-12 months and among male (62.2%. The most prevalent SGTs were 19 followed by 10, 14 and 7; 21 per cent of isolates belonging to serotype 10 (n=7 were 11 (n=4 were not covered in any of the conjugate vaccines currently available in Indian market. Resistance to co-trimoxazole, tetracycline, penicillin and erythromycin was observed in 91 per cent (n=48, 36 per cent (n=19, 17 per cent (n=9 and 9 per cent (n=5 isolates, respectively. All the penicillin resistant isolates were found to be intermediately resistant by E-Test. Multidrug resistance was observed in 19 per cent (n=10 isolates. Interpretation & conclusions: High level of antibiotic resistance was present in S. pneumoniae isolated from healthy children below age five. A pneumococcal conjugate vaccine with the prevailing SGTs would help to reduce the pool of antibiotic resistant pneumococci. Continued surveillance of serotypes and tracking

  9. 19F NMR method for the determination of quality of virgin olive oil

    Directory of Open Access Journals (Sweden)

    Zhou, L. L.

    2015-12-01

    Full Text Available This paper reported a potential analytical technique based on NMR spectroscopy for the determination of quality of olive oil. The model compounds with active hydrogen, including free sterols, free aliphatic alcohols, phenolics, and free fatty acids were determined by 19F NMR upon derivation with 4-fluorobenzoyl chloride. Integration of the appropriate signals of the derivatives of the compounds in the corresponding 19F NMR spectrum allows for the quantification of these compounds. 37 Samples of commercial olive oil and 5 samples of other plant oils were determined by 19F NMR. The amount of diglycerides and the ratio of 1,2-diglycerides to the total amount of diglycerides were analyzed to monitor whether extra virgin olive oil was adulterated with low price olive oil and other plant oils or not. The results showed that the total diglyceride content should not be higher than 2.5% and the ratio (D of 1,2-diglycerides to total diglycerides should be higher than 0.35 for extra virgin olive oil. This method is an easier, simpler, safer, faster and more reliable technique for the determination of the quality of olive oil and can also be extended to monitoring the quality of ordinary edible oils.En este trabajo se describe una técnica analítica basada en la espectroscopía de RMN para determinar la calidad del aceite de oliva. Los compuestos modelo con hidrógeno activo, incluyendo esteroles libres, alcoholes alifáticos libres, compuestos fenólicos, ácidos grasos libres se determinaron por 19F RMN derivatizados con cloruro de 4-fluorobenzoilo. La integración de las señales apropiadas de los derivados de los compuestos en el correspondiente espectro de 19F RMN permite la cuantificación de estos compuestos. 37 muestras de aceites de oliva comerciales y 5 muestras de otros aceites vegetales se determinaron por 19F RMN. La cantidad de diglicéridos y la proporción de los 1,2-diglicéridos a la cantidad total de diglicéridos se analizaron para

  10. A Salmonella Typhimurium-Typhi genomic chimera: a model to study Vi polysaccharide capsule function in vivo.

    Directory of Open Access Journals (Sweden)

    Angela M Jansen

    2011-07-01

    Full Text Available The Vi capsular polysaccharide is a virulence-associated factor expressed by Salmonella enterica serotype Typhi but absent from virtually all other Salmonella serotypes. In order to study this determinant in vivo, we characterised a Vi-positive S. Typhimurium (C5.507 Vi(+, harbouring the Salmonella pathogenicity island (SPI-7, which encodes the Vi locus. S. Typhimurium C5.507 Vi(+ colonised and persisted in mice at similar levels compared to the parent strain, S. Typhimurium C5. However, the innate immune response to infection with C5.507 Vi(+ and SGB1, an isogenic derivative not expressing Vi, differed markedly. Infection with C5.507 Vi(+ resulted in a significant reduction in cellular trafficking of innate immune cells, including PMN and NK cells, compared to SGB1 Vi(- infected animals. C5.507 Vi(+ infection stimulated reduced numbers of TNF-α, MIP-2 and perforin producing cells compared to SGB1 Vi(-. The modulating effect associated with Vi was not observed in MyD88(-/- and was reduced in TLR4(-/- mice. The presence of the Vi capsule also correlated with induction of the anti-inflammatory cytokine IL-10 in vivo, a factor that impacted on chemotaxis and the activation of immune cells in vitro.

  11. Activation of antitumor immune responses by Ganoderma formosanum polysaccharides in tumor-bearing mice.

    Science.gov (United States)

    Wang, Cheng-Li; Lu, Chiu-Ying; Hsueh, Ying-Chao; Liu, Wen-Hsiung; Chen, Chun-Jen

    2014-11-01

    Fungi of the genus Ganoderma are basidiomycetes that have been used as traditional medicine in Asia and have been shown to exhibit various pharmacological activities. We recently found that PS-F2, a polysaccharide fraction purified from the submerged culture broth of Ganoderma formosanum, stimulates the maturation of dendritic cells and primes a T helper 1 (Th1)-polarized adaptive immune response in vivo. In this study, we investigated whether the immune adjuvant function of PS-F2 can stimulate antitumor immune responses in tumor-bearing mice. Continuous intraperitoneal or oral administration of PS-F2 effectively suppressed the growth of colon 26 (C26) adenocarcinoma, B16 melanoma, and sarcoma 180 (S180) tumor cells in mice without adverse effects on the animals' health. PS-F2 did not cause direct cytotoxicity on tumor cells, and it lost the antitumor effect in mice with severe combined immunodeficiency (SCID). CD4(+) T cells, CD8(+) T cells, and serum from PS-F2-treated tumor-bearing mice all exhibited antitumor activities when adoptively transferred to naïve animals, indicating that PS-F2 treatment stimulates tumor-specific cellular and humoral immune responses. These data demonstrate that continuous administration of G. formosanum polysaccharide PS-F2 can activate host immune responses against ongoing tumor growth, suggesting that PS-F2 can potentially be developed into a preventive/therapeutic agent for cancer immunotherapy.

  12. Salmonella serotypes in reptiles and humans, French Guiana.

    Science.gov (United States)

    Gay, Noellie; Le Hello, Simon; Weill, François-Xavier; de Thoisy, Benoit; Berger, Franck

    2014-05-14

    In French Guiana, a French overseas territory located in the South American northern coast, nearly 50% of Salmonella serotypes isolated from human infections belong to serotypes rarely encountered in metropolitan France. A reptilian source of contamination has been investigated. Between April and June 2011, in the area around Cayenne, 151 reptiles were collected: 38 lizards, 37 snakes, 32 turtles, 23 green iguanas and 21 caimans. Cloacal swab samples were collected and cultured. Isolated Salmonella strains were identified biochemically and serotyped. The overall carriage frequency of carriage was 23.2% (95% confidence interval: 16.7-30.4) with 23 serotyped strains. The frequency of Salmonella carriage was significantly higher for wild reptiles. Near two-thirds of the Salmonella serotypes isolated from reptiles were also isolated from patients in French Guiana. Our results highlight the risk associated with the handling and consumption of reptiles and their role in the spread of Salmonella in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Antibiotic Susceptibilities and Serotyping of Clinical Streptococcus Agalactiae Isolates

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    Altay Atalay

    2011-11-01

    Full Text Available Objective: Streptococcus agalactiae (Group B streptococci, GBS are frequently responsible for sepsis and meningitis seen in the early weeks of life. GBS may cause perinatal infection and premature birth in pregnant women. The aim of this study was to serotype GBS strains isolated from clinical samples and evaluate their serotype distribution according to their susceptibilities to antibiotics and isolation sites. Material and Methods: One hundred thirty one S. agalactiae strains isolated from the clinical samples were included in the study. Of the strains, 99 were isolated from urine, 20 from soft tissue, 10 from blood and 2 from vaginal swab. Penicillin G and ceftriaxone susceptibilities of GBS were determined by the agar dilution method. Susceptibilities to erythromycin, clindamycin, vancomycin and tetracycline were determined by the Kirby-Bauer method according to CLSI criteria. Serotyping was performed using the latex aglutination method using specific antisera (Ia, Ib, II-VIII. Results: While in 131 GBS strains, serotypes VII and VIII were not detected, the most frequently isolated serotypes were types Ia (36%, III (30.5% and II (13% respectively. Serotype Ia was the most frequently seen serotype in all samples. All GBS isolates were susceptible to penicilin G, ceftriaxone and vancomycin. Among the strains, tetracycline, erythromycin and clindamycin resistance rates were determined as 90%, 14.5%, and 13% respectively. Conclusion: Penicillin is still the first choice of treatment for the infections with all serotypes of S. agalactiae in Turkey.

  14. Surface-bound capsular polysaccharide of type Ia group B Streptococcus mediates C1 binding and activation of the classic complement pathway

    International Nuclear Information System (INIS)

    Levy, N.J.; Kasper, D.L.

    1986-01-01

    The role of surface-bound type Ia group B Streptococcus (GBS) capsular polysaccharide in anti-body-independent binding of C1 and activation of the classic component pathway was investigated. In a radiolabeled bacterial-polymorphonuclear leukocyte (PMN) association assay, a measure of bacterial opsonization, preincubation of 3 H-type Ia GBS with purified F(ab') 2 to the organism blocked the association of the bacteria with PMN', and the inhibitory effect was dose dependent. The specificity of F(ab') 2 blocking was shown after adsorption of F(ab') 2 with type Ia polysaccharide-sensitized erythrocytes. Polysaccharide-adsorbed F(ab') 2 had a 70% decrease in ability to block the association of bacteria with PMN. Neuraminidase digestion removed 80% of the terminal sialic acid residues from the native polysaccharide. These neuraminidase-digested organisms had a 72% decrease in binding and transfer of purified C1 compared with non-enzyme-treated organisms. Type Ia capsular polysaccharide bound to sheep erythrocytes promoted classic complement pathway-mediated hemolysis of the cells. The role of C1 inhibitor (INH) in modulation of C1 activation by the organisms was investigated. The possibility existed that the C1 INH could be bound by the bacteria, allowing C1 activation to occur in the fluid phase. The inhibitor was purified from human serum, and its activity was measured before and after incubation with type Ia GBS. The organisms had no effect on C1 INH activity. Thus surface-bound capsular polysacchardie of type Ia GBS mediates C1 binding and classic pathway activation, and this does not involve the C1 INH

  15. Polysaccharide charge density regulating protein adsorption to air/water interfaces by protein/polysaccharide complex formation

    NARCIS (Netherlands)

    Ganzevles, R.A.; Kosters, H.; Vliet, T. van; Stuart, M.A.C.; Jongh, H.H.J. de

    2007-01-01

    Because the formation of protein/polysaccharide complexes is dominated by electrostatic interaction, polysaccharide charge density is expected to play a major role in the adsorption behavior of the complexes. In this study, pullulan (a non-charged polysaccharide) carboxylated to four different

  16. Characterization and validation of noninvasive oxygen tension measurements in human glioma xenografts by 19F-MR relaxometry

    International Nuclear Information System (INIS)

    Sanden, Boudewijn P.J. van der; Heerschap, Arend; Simonetti, Arjan W.; Rijken, Paul F.J.W.; Peters, Hans P.W.; Stbeen, Georg; Kogel, Albert J. van der

    1999-01-01

    Purpose: The aim of this study was to characterize and to validate noninvasive 19 F-magnetic resonance relaxometry for the measurement of oxygen tensions in human glioma xenografts in nude mice. The following three questions were addressed: 1. When perfluorocarbon compounds (PFCs) are administrated intravenously, which tumor regions are assessed by 19 F-MR relaxometry? 2. Are oxygen tension as detected by 19 F-MR relaxometry (pO 2/relaxo ) comparable to Eppendorf O 2 -electrode measurements (pO 2/electrode )? 3. Can 19 F-MR relaxometry be used to detect oxygen tension changes in tumor tissue during carbogen breathing? Methods and Materials: Slice-selective 19 F-MR relaxometry was carried out with perfluoro-15-crown-5-ether as oxygen sensor. The PFC was injected i.v. 3 days before the 19 F-MR experiments. Two datasets were acquired before and two after the start of carbogen breathing. The distribution of PFCs and necrotic areas were analyzed in 19 F-Spin Echo (SE) density MR images and T 2 -weighted 1 H-SE MR images, respectively. One day after the MR investigations, oxygen tensions were measured by oxygen electrodes in the same slice along two perpendicular tracks. These measurements were followed by (immuno)histochemical analysis of the 2D distribution of perfused microvessels, hypoxic cells, necrotic areas, and macrophages. Results: The PFCs mainly became sequestered in perfused regions at the tumor periphery; thus, 19 F-MR relaxometry probed mean oxygen tensions in these regions throughout the selected MR slice. In perfused regions of the tumor, mean pO 2/relaxo values were comparable to mean pO 2/electrode values, and varied from 0.03 to 9 mmHg. Median pO 2/electrode values of both tracks were lower than mean pO 2/relaxo values, because low pO 2/electrode values that originate from hypoxic and necrotic areas were also included in calculations of median pO 2/electrode values. After 8-min carbogen breathing, the average pO 2/relaxo increase was 3.3 ± 0.8 (SEM

  17. Sulfated modification and anticoagulant activity of pumpkin (Cucurbita pepo, Lady Godiva) polysaccharide.

    Science.gov (United States)

    Liang, Li; Ao, Le; Ma, Tao; Ni, Yuanying; Liao, Xiaojun; Hu, Xiaosong; Song, Yi

    2018-01-01

    Sulfated modification of pumpkin polysaccharide using CAS with pyridines as catalysts under different conditions was conducted to obtain different degrees of sulfation on a laboratory scale. Anticoagulant activities of pumpkin polysaccharide and its sulfated derivatives were also investigated employing various established in vitro systems. Results showed that addition of high ratio of CAS/pyridine under constant conditions could increase the degree of substitution. Sulfate substitution was further confirmed by the FT-IR and 13 C NMR analysis. The d f values between 2.11-2.73 indicated the relatively expanded conformation of the sulfated derivatives. The sulfated polysaccharides showed higher anticoagulant activities through activated partial thrombosis time (aPTT), thrombin time (TT), prothrombin time (PT) and anti-Xa activity assay, which revealed that better anticoagulant activities could be obtained when DS remained higher and M w maintained in a moderate range. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Detection of site-specific binding and co-binding of ligands to macromolecules using 19F NMR

    International Nuclear Information System (INIS)

    Jenkins, B.G.

    1991-01-01

    Study of ligand-macromolecular interactions by 19 F nuclear magnetic resonance (NMR) spectroscopy affords many opportunities for obtaining molecular biochemical and pharmaceutical information. This is due to the absence of a background fluorine signal, as well as the relatively high sensitivity of 19 F NMR. Use of fluorine-labeled ligands enables one to probe not only binding and co-binding phenomena to macromolecules, but also can provide data on binding constants, stoichiometries, kinetics, and conformational properties of these complexes. Under conditions of slow exchange and macromolecule-induced chemical shifts, multiple 19 F NMR resonances can be observed for free and bound ligands. These shifted resonances are a direct correlate of the concentration of ligand bound in a specific state rather than the global concentrations of bound or free ligand which are usually determined using other techniques such as absorption spectroscopy or equilibrium dialysis. Examples of these interactions are demonstrated both from the literature and from interactions of 5-fluorotryptophan, 5-fluorosalicylic acid, flurbiprofen, and sulindac sulfide with human serum albumin. Other applications of 19 F NMR to study of these interactions in vivo, as well for receptor binding and metabolic tracing of fluorinated drugs and proteins are discussed

  19. Dynamic polarization of 19F in a fluorinated alcohol

    International Nuclear Information System (INIS)

    Hill, D.; Kasprzyk, T.; Jarmer, J.J.; Penttilae, S.; Krumpolc, M.; Hoffmann, G.W.; Purcell, M.

    1988-01-01

    We have studied microwave dynamic cooling of 19 F and 1 H nuclei in mixtures of 1,1,1,3,3,3-hexafluoro-2-propanol and water, doped with Cr(V) complex. Equal spin temperatures of the two nuclei are produced, and the highest spin polarizations (/approximately/80%) are found in mixtures near the eutectic ratio. The high fluorine content and polarization make this a suitable material for polarized nuclear scattering experiments. 11 refs., 3 figs., 1 tab

  20. Biochemical evaluation of antioxidant activity and polysaccharides fractions in seaweeds

    Directory of Open Access Journals (Sweden)

    A. Tariq

    2015-01-01

    Full Text Available In the present study ethanol and water extracts of 15 seaweeds, Dictyota dichotoma var. velutricata, Dictyota indica, Iyengaria stellata, Padina pavonia, Sargassum swartzii, Sargassum variegatum, Stoechospermum marginatum, Stokeyia indica, Jolyna laminarioides, Caulerpa taxifolia, Halimeda tuna, Ulva fasciata, Ulva lactuca, Solieria robusta, and Melanothamnus afaqhusainii, were evaluated for their antioxidant potential by ABTS or 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, superoxide and total antioxidant capacity (TAC assays.  The activity was concentration dependent and the variation in antioxidant potential was also observed by different assays in both extracts.  Ethanol extract of D. dichotoma var. velutricata, D. indica and S. marginatum demonstrated highest activity by TAC assay.  The antioxidant potential in organic solvent fractions of seaweeds namely P. pavonia, S. swartzii, S. marginatum and M. afaqhusainii was also determined and chloroform fraction of all the four seaweeds showed highest activity by superoxide assay.  Antioxidant activity of extracted fractions of polysaccharides from S. indica, C. taxifolia and D. dichotoma var. velutricata was also evaluated by superoxide method.  Polysaccharide fractions of S. indica obtained from HCl (at 700C and room temperature and water extract demonstrated highest activity respectively.  All the polysaccharide fractions of C. taxifolia showed excellent activity except CaClF70°C. Polysaccharide fractions of D. dichotoma var. velutricata also exhibited very good activity.

  1. {sup 19}F-labeling of the adenine H2-site to study large RNAs by NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sochor, F. [Johann Wolfgang Goethe-University Frankfurt, Institut für Organische Chemie und Chemische Biologie, Center for Biomolecular Magnetic Resonance (BMRZ) (Germany); Silvers, R. [Massachusetts Institute of Technology, Department of Chemistry, Francis Bitter Magnet Laboratory (United States); Müller, D.; Richter, C.; Fürtig, B., E-mail: fuertig@nmr.uni-frankfurt.de; Schwalbe, H., E-mail: schwalbe@nmr.uni-frankfurt.de [Johann Wolfgang Goethe-University Frankfurt, Institut für Organische Chemie und Chemische Biologie, Center for Biomolecular Magnetic Resonance (BMRZ) (Germany)

    2016-01-15

    In comparison to proteins and protein complexes, the size of RNA amenable to NMR studies is limited despite the development of new isotopic labeling strategies including deuteration and ligation of differentially labeled RNAs. Due to the restricted chemical shift dispersion in only four different nucleotides spectral resolution remains limited in larger RNAs. Labeling RNAs with the NMR-active nucleus {sup 19}F has previously been introduced for small RNAs up to 40 nucleotides (nt). In the presented work, we study the natural occurring RNA aptamer domain of the guanine-sensing riboswitch comprising 73 nucleotides from Bacillus subtilis. The work includes protocols for improved in vitro transcription of 2-fluoroadenosine-5′-triphosphat (2F-ATP) using the mutant P266L of the T7 RNA polymerase. Our NMR analysis shows that the secondary and tertiary structure of the riboswitch is fully maintained and that the specific binding of the cognate ligand hypoxanthine is not impaired by the introduction of the {sup 19}F isotope. The thermal stability of the {sup 19}F-labeled riboswitch is not altered compared to the unmodified sequence, but local base pair stabilities, as measured by hydrogen exchange experiments, are modulated. The characteristic change in the chemical shift of the imino resonances detected in a {sup 1}H,{sup 15}N-HSQC allow the identification of Watson–Crick base paired uridine signals and the {sup 19}F resonances can be used as reporters for tertiary and secondary structure transitions, confirming the potential of {sup 19}F-labeling even for sizeable RNAs in the range of 70 nucleotides.

  2. Optimization of Alkaline Extraction and Bioactivities of Polysaccharides from Rhizome of Polygonatum odoratum

    Science.gov (United States)

    Chen, Yong; Yin, Luoyi; Zhang, Xuejiao; Wang, Yan; Chen, Qiuzhi; Jin, Chenzhong; Wang, Jihua

    2014-01-01

    The present study is to explore the optimal extraction parameters, antioxidant activity, and antimicrobial activity of alkaline soluble polysaccharides from rhizome of Polygonatum odoratum. The optimal extraction parameters were determined as the following: NaOH concentration (A) 0.3 M, temperature (B) 80°C, ratio of NaOH to solid (C) 10-fold, and extraction time (D) 4 h, in which ratio of NaOH to solid was a key factor. The order of the factors was ratio of NaOH to solid (fold, C) > extraction temperature (°C, B) > NaOH concentration (M, A) > extraction time (h, D). The monosaccharide compositions of polysaccharides from P. odoratum were rhamnose, mannose, xylose, and arabinose with the molecular ratio of 31.78, 31.89, 11.11, and 1.00, respectively. The reducing power, the 1, 1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging rate, the hydroxyl radicals scavenging rate, and the inhibition rate to polyunsaturated fatty acid (PUFA) peroxidation of the alkaline soluble polysaccharides from P. odoratum at 1 mg/mL were 9.81%, 52.84%, 19.22%, and 19.42% of ascorbic acid at the same concentration, respectively. They also showed antimicrobial activity against pathogenic bacteria Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, and Escherichia coli. PMID:25093173

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

    Science.gov (United States)

    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.

  4. TANK 18 AND 19-F TIER 1A EQUIPMENT FILL MOCK UP TEST SUMMARY

    Energy Technology Data Exchange (ETDEWEB)

    Stefanko, D.; Langton, C.

    2011-11-04

    The United States Department of Energy (US DOE) has determined that Tanks 18-F and 19-F have met the F-Tank Farm (FTF) General Closure Plan Requirements and are ready to be permanently closed. The high-level waste (HLW) tanks have been isolated from FTF facilities. To complete operational closure they will be filled with grout for the purpose of: (1) physically stabilizing the tanks, (2) limiting/eliminating vertical pathways to residual waste, (3) discouraging future intrusion, and (4) providing an alkaline, chemical reducing environment within the closure boundary to control speciation and solubility of select radionuclides. Bulk waste removal and heel removal equipment remain in Tanks 18-F and 19-F. This equipment includes the Advance Design Mixer Pump (ADMP), transfer pumps, transfer jets, standard slurry mixer pumps, equipment-support masts, sampling masts, dip tube assemblies and robotic crawlers. The present Tank 18 and 19-F closure strategy is to grout the equipment in place and eliminate vertical pathways by filling voids in the equipment to vertical fast pathways and water infiltration. The mock-up tests described in this report were intended to address placement issues identified for grouting the equipment that will be left in Tank 18-F and Tank 19-F. The Tank 18-F and 19-F closure strategy document states that one of the Performance Assessment (PA) requirements for a closed tank is that equipment remaining in the tank be filled to the extent practical and that vertical flow paths 1 inch and larger be grouted. The specific objectives of the Tier 1A equipment grout mock-up testing include: (1) Identifying the most limiting equipment configurations with respect to internal void space filling; (2) Specifying and constructing initial test geometries and forms that represent scaled boundary conditions; (3) Identifying a target grout rheology for evaluation in the scaled mock-up configurations; (4) Scaling-up production of a grout mix with the target rheology

  5. 19 CFR 12.104f - Temporary disposition of materials and articles.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Temporary disposition of materials and articles... SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Cultural Property § 12.104f Temporary... museum or other cultural or scientific institution in the U.S. if he finds that sufficient safeguards...

  6. The F4 fimbrial antigen of Escherichia coli and its receptors.

    NARCIS (Netherlands)

    Van den Broeck, W; Cox, E; Oudega, B.; Goddeeris, B

    2000-01-01

    F4 or K88 fimbriae are long filamentous polymeric surface proteins of enterotoxigenic Escherichia coli (ETEC), consisting of so-called major (FaeG) and minor (FaeF, FaeH, FaeC, and probably FaeI) subunits. Several serotypes of F4 have been described, namely F4ab, F4ac, and F4ad. The F4 fimbriae

  7. Molecular diagnosis of non-serotypeable Shigella spp.: problems and prospects.

    Science.gov (United States)

    Muthuirulandi Sethuvel, Dhiviya Prabaa; Devanga Ragupathi, Naveen Kumar; Anandan, Shalini; Walia, Kamini; Veeraraghavan, Balaji

    2017-02-01

    It is not always possible to identify Shigella serogroups/serotypes by biochemical properties alone. Specific identification requires serotyping. Occasionally, isolates that resemble Shigella spp. biochemically, but are non-agglutinable with available antisera, have been observed. Several mechanisms have been reported to limit the efficiency of the serotyping assay. Serotype conversion is a major mechanism in Shigella spp. to escape protective host immune responses. This easy conversion through significant modification of the O-antigen backbone results in different serotypes, which makes laboratory identification difficult. Furthermore, members of the family Enterobacteriaceae are closely related and there is antigenic cross-over (intra- and inter-specific cross-reaction) which affects the agglutination reaction. The performance of the available methods for identification of non-serotypeable Shigella is discussed here, and reveals them to be non-reliable. This shows a need for an alternative method for identification and typing of Shigella spp.

  8. K19 capsular polysaccharide of Acinetobacter baumannii is produced via a Wzy polymerase encoded in a small genomic island rather than the KL19 capsule gene cluster.

    Science.gov (United States)

    Kenyon, Johanna J; Shneider, Mikhail M; Senchenkova, Sofya N; Shashkov, Alexander S; Siniagina, Maria N; Malanin, Sergey Y; Popova, Anastasiya V; Miroshnikov, Konstantin A; Hall, Ruth M; Knirel, Yuriy A

    2016-08-01

    Polymerization of the oligosaccharides (K units) of complex capsular polysaccharides (CPSs) requires a Wzy polymerase, which is usually encoded in the gene cluster that directs K unit synthesis. Here, a gene cluster at the Acinetobacter K locus (KL) that lacks a wzy gene, KL19, was found in Acinetobacter baumannii ST111 isolates 28 and RBH2 recovered from hospitals in the Russian Federation and Australia, respectively. However, these isolates produced long-chain capsule, and a wzy gene was found in a 6.1 kb genomic island (GI) located adjacent to the cpn60 gene. The GI also includes an acetyltransferase gene, atr25, which is interrupted by an insertion sequence (IS) in RBH2. The capsule structure from both strains was →3)-α-d-GalpNAc-(1→4)-α-d-GalpNAcA-(1→3)-β-d-QuipNAc4NAc-(1→, determined using NMR spectroscopy. Biosynthesis of the K unit was inferred to be initiated with QuiNAc4NAc, and hence the Wzy forms the β-(1→3) linkage between QuipNAc4NAc and GalpNAc. The GalpNAc residue is 6-O-acetylated in isolate 28 only, showing that atr25 is responsible for this acetylation. The same GI with or without an IS in atr25 was found in draft genomes of other KL19 isolates, as well as ones carrying a closely related CPS gene cluster, KL39, which differs from KL19 only in a gene for an acyltransferase in the QuiNAc4NR synthesis pathway. Isolates carrying a KL1 variant with the wzy and atr genes each interrupted by an ISAba125 also have this GI. To our knowledge, this study is the first report of genes involved in capsule biosynthesis normally found at the KL located elsewhere in A. baumannii genomes.

  9. Update on: Shigella new serogroups/serotypes and their antimicrobial resistance.

    Science.gov (United States)

    Muthuirulandi Sethuvel, D P; Devanga Ragupathi, N K; Anandan, S; Veeraraghavan, B

    2017-01-01

    Shigellosis represents a major burden of disease in developing countries. A low infectious dose allows the disease to be spread effectively. Although shigellosis is mostly a self-limiting disease, antibiotics are recommended to reduce deaths, disease symptoms and organism-shedding time. However, in India, antimicrobial resistance among the genus Shigella is more common than among any other enteric bacteria. Notably, new serotypes or subserotypes in Shigella are reported from various parts of the world. Identification of new subserotypes of Shigella spp. is becoming a major issue as these strains are nontypeable by conventional serotyping. The commercially available antisera may not cover all possible epitopes of the O lipopolysaccharide antigen of Shigella serotypes. Therefore, molecular methods which most closely approach the resolution of full serotyping are necessary to identify such strains. In addition, the knowledge of a prevalent serotype in various geographic regions may assist in formulating strategies such as the development of a vaccine to prevent infection especially when the immunity to disease is serotype specific, and to understand the disease burden caused by new Shigella serotypes. © 2016 The Society for Applied Microbiology.

  10. Serotype diversity of astroviruses in Rawalpindi, Pakistan during 2009-2010.

    Directory of Open Access Journals (Sweden)

    Muhammad Masroor Alam

    Full Text Available Astroviruses are globally known enteropathogens causing gastroenteritis and diarrhea, with eight well defined serotypes. Epidemiological studies have recognized serotype-1 as the most common subtype but no such data is available in Pakistan. During 2009-2010, we found astroviruses in 41 out of 535 (7% samples collected from hospitalized children. Thirty one strains belonged to serotype-1 and clustered into two distinct lineages. Serotype-3, -4 and -6 were detected with 97-98% genetic homology to Indian and Chinese strains.

  11. Lung abscess caused by Streptococcus pneumoniae serotype 6B

    Directory of Open Access Journals (Sweden)

    Yuhei Ito

    Full Text Available Lung abscess has been considered to be a rare complication of pneumococcal infection, and most cases are reported to be Streptococcus pneumoniae serotype 3. A 67-year-old man presented with fever and was diagnosed to have lung abscess caused by S. pneumoniae serotype 6B. The minimal inhibitory concentration (MIC of penicillin for the isolate was 1 μg/mL. He was treated with high-dose intravenous sulbactam/ampicillin as definitive therapy based on susceptibility testing for S. pneumoniae and recovered successfully without surgical intervention. S. pneumoniae serotype 6B can cause lung abscess. Keywords: Streptococcus pneumoniae, Lung abscess, Serotype 6B, Penicillin-resistant Streptococcus pneumoniae

  12. Safety and immunogenicity of neonatal pneumococcal conjugate vaccination in Papua New Guinean children: a randomised controlled trial.

    Directory of Open Access Journals (Sweden)

    William S Pomat

    Full Text Available Approximately 826,000 children, mostly young infants, die annually from invasive pneumococcal disease. A 6-10-14-week schedule of pneumococcal conjugate vaccine (PCV is efficacious but neonatal PCV may provide earlier protection and better coverage. We conducted an open randomized controlled trial in Papua New Guinea to compare safety, immunogenicity and priming for memory of 7-valent PCV (PCV7 given in a 0-1-2-month (neonatal schedule with that of the routine 1-2-3-month (infant schedule.We randomized 318 infants at birth to receive PCV7 in the neonatal or infant schedule or no PCV7. All infants received 23-valent pneumococcal polysaccharide vaccine (PPV at age 9 months. Serotype-specific serum IgG for PCV7 (VT serotypes and non-VT serotypes 2, 5 and 7F were measured at birth and 2, 3, 4, 9, 10 and 18 months of age. Primary outcomes were geometric mean concentrations (GMCs and proportions with concentration ≥ 0.35 µg/ml of VT serotype-specific pneumococcal IgG at age 2 months and one month post-PPV.We enrolled 101, 105 and 106 infants, respectively, into neonatal, infant and control groups. Despite high background levels of maternally derived antibody, both PCV7 groups had higher GMCs than controls at age 2 months for serotypes 4 (p<0.001 and 9V (p<0.05 and at age 3 months for all VTs except 6B. GMCs for serotypes 4, 9V, 18C and 19F were significantly higher (p<0.001 at age 2 months in the neonatal (one month post-dose2 PCV7 than in the infant group (one month post-dose1 PCV7. PPV induced significantly higher VT antibody responses in PCV7-primed than unprimed infants, with neonatal and infant groups equivalent. High VT and non-VT antibody concentrations generally persisted to age 18 months.PCV7 is well-tolerated and immunogenic in PNG neonates and young infants and induces immunologic memory to PPV booster at age 9 months with antibody levels maintained to age 18 months.ClinicalTrials.gov NCT00219401.

  13. Ganoderma lucidum polysaccharides in human monocytic leukemia cells: from gene expression to network construction

    Directory of Open Access Journals (Sweden)

    Ou Chern-Han

    2007-11-01

    Full Text Available Abstract Background Ganoderma lucidum has been widely used as a herbal medicine for promoting health and longevity in China and other Asian countries. Polysaccharide extracts from Ganoderma lucidum have been reported to exhibit immuno-modulating and anti-tumor activities. In previous studies, F3, the active component of the polysaccharide extract, was found to activate various cytokines such as IL-1, IL-6, IL-12, and TNF-α. This gave rise to our investigation on how F3 stimulates immuno-modulating or anti-tumor effects in human leukemia THP-1 cells. Results Here, we integrated time-course DNA microarray analysis, quantitative PCR assays, and bioinformatics methods to study the F3-induced effects in THP-1 cells. Significantly disturbed pathways induced by F3 were identified with statistical analysis on microarray data. The apoptosis induction through the DR3 and DR4/5 death receptors was found to be one of the most significant pathways and play a key role in THP-1 cells after F3 treatment. Based on time-course gene expression measurements of the identified pathway, we reconstructed a plausible regulatory network of the involved genes using reverse-engineering computational approach. Conclusion Our results showed that F3 may induce death receptor ligands to initiate signaling via receptor oligomerization, recruitment of specialized adaptor proteins and activation of caspase cascades.

  14. Ganoderma lucidum polysaccharides in human monocytic leukemia cells: from gene expression to network construction.

    Science.gov (United States)

    Cheng, Kun-Chieh; Huang, Hsuan-Cheng; Chen, Jenn-Han; Hsu, Jia-Wei; Cheng, Hsu-Chieh; Ou, Chern-Han; Yang, Wen-Bin; Chen, Shui-Tein; Wong, Chi-Huey; Juan, Hsueh-Fen

    2007-11-09

    Ganoderma lucidum has been widely used as a herbal medicine for promoting health and longevity in China and other Asian countries. Polysaccharide extracts from Ganoderma lucidum have been reported to exhibit immuno-modulating and anti-tumor activities. In previous studies, F3, the active component of the polysaccharide extract, was found to activate various cytokines such as IL-1, IL-6, IL-12, and TNF-alpha. This gave rise to our investigation on how F3 stimulates immuno-modulating or anti-tumor effects in human leukemia THP-1 cells. Here, we integrated time-course DNA microarray analysis, quantitative PCR assays, and bioinformatics methods to study the F3-induced effects in THP-1 cells. Significantly disturbed pathways induced by F3 were identified with statistical analysis on microarray data. The apoptosis induction through the DR3 and DR4/5 death receptors was found to be one of the most significant pathways and play a key role in THP-1 cells after F3 treatment. Based on time-course gene expression measurements of the identified pathway, we reconstructed a plausible regulatory network of the involved genes using reverse-engineering computational approach. Our results showed that F3 may induce death receptor ligands to initiate signaling via receptor oligomerization, recruitment of specialized adaptor proteins and activation of caspase cascades.

  15. Lessons From Globally Coordinated Cessation of Serotype 2 Oral Poliovirus Vaccine for the Remaining Serotypes.

    Science.gov (United States)

    Thompson, Kimberly M; Duintjer Tebbens, Radboud J

    2017-07-01

    Comparing model expectations with the experience of oral poliovirus vaccine (OPV) containing serotype 2 (OPV2) cessation can inform risk management for the expected cessation of OPV containing serotypes 1 and 3 (OPV13). We compare the expected post-OPV2-cessation OPV2-related viruses from models with the evidence available approximately 6 months after OPV2 cessation. We also model the trade-offs of use vs nonuse of monovalent OPV (mOPV) for outbreak response considering all 3 serotypes. Although too early to tell definitively, the observed die-out of OPV2-related viruses in populations that attained sufficiently intense trivalent OPV (tOPV) use prior to OPV2 cessation appears consistent with model expectations. As expected, populations that did not intensify tOPV use prior to OPV2 cessation show continued circulation of serotype 2 vaccine-derived polioviruses (VDPVs). Failure to aggressively use mOPV to respond to circulating VDPVs results in a high risk of uncontrolled outbreaks that would require restarting OPV. Ensuring a successful endgame requires more aggressive OPV cessation risk management than has occurred to date for OPV2 cessation. This includes maintaining high population immunity to transmission up until OPV13 cessation, meeting all prerequisites for OPV cessation, and ensuring sufficient vaccine supply to prevent and respond to outbreaks. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  16. A generalized strategy for designing (19)F/(1)H dual-frequency MRI coil for small animal imaging at 4.7 Tesla.

    Science.gov (United States)

    Hu, Lingzhi; Hockett, Frank D; Chen, Junjie; Zhang, Lei; Caruthers, Shelton D; Lanza, Gregory M; Wickline, Samuel A

    2011-07-01

    To propose and test a universal strategy for building (19) F/(1) H dual-frequency RF coil that permits multiple coil geometries. The feasibility to design (19) F/(1) H dual-frequency RF coil based on coupled resonator model was investigated. A series capacitive matching network enables robust impedance matching for both harmonic oscillating modes of the coupled resonator. Two typical designs of (19) F/(1) H volume coils (birdcage and saddle) at 4.7T were implemented and evaluated with electrical bench test and in vivo (19) F/(1) H dual-nuclei imaging. For various combinations of internal resistances of the sample coil and secondary resonator, numerical solutions for the tunable capacitors to optimize impedance matching were obtained using a root-seeking program. Identical and homogeneous B1 field distribution at (19) F and (1) H frequencies were observed in bench test and phantom image. Finally, in vivo mouse imaging confirmed the sensitivity and homogeneity of the (19) F/(1) H dual-frequency coil design. A generalized strategy for designing (19) F/(1) H dual-frequency coils based on the coupled resonator approach was developed and validated. A unique feature of this design is that it preserves the B1 field homogeneity of the RF coil at both resonant frequencies. Thus it minimizes the susceptibility effect on image co-registration. Copyright © 2011 Wiley-Liss, Inc.

  17. Radiation processed polysaccharide products

    International Nuclear Information System (INIS)

    Nguyen, Quoc Hien

    2007-01-01

    Radiation crosslinking, degradation and grafting techniques for modification of polymeric materials including natural polysaccharides have been providing many unique products. In this communication, typical products from radiation processed polysaccharides particularly plant growth promoter from alginate, plant protector and elicitor from chitosan, super water absorbent containing starch, hydrogel sheet containing carrageenan/CM-chitosan as burn wound dressing, metal ion adsorbent from partially deacetylated chitin were described. The procedures for producing those above products were also outlined. Future development works on radiation processing of polysaccharides were briefly presented. (author)

  18. Nuclear reactions in AGB nucleosynthesis: the 19F(α, p22Ne at energies of astrophysical relevance

    Directory of Open Access Journals (Sweden)

    D’Agata G.

    2017-01-01

    Full Text Available The abundance of 19F in the universe is strictly related to standard and extra-mixing processes taking place inside AGB-stars, that are considered to be the most important sites for its production. Nevertheless the way in which it is destroyed is far from being well understood. For this reason we studied the 19F(α,p22Ne reaction, that is supposed to be the main destruction channel in the Helium-rich part of the star. In this experiment, the reaction has been studied in the energy range of relevance for astrophysics (0÷1 MeV via the Trojan Horse Method (THM, using the three-body reaction 6Li(19F,p22Ned.

  19. The Widespread Multidrug-Resistant Serotype O12 Pseudomonas aeruginosa Clone Emerged through Concomitant Horizontal Transfer of Serotype Antigen and Antibiotic Resistance Gene Clusters

    DEFF Research Database (Denmark)

    Thrane, Sandra Wingaard; Taylor, Véronique L.; Freschi, Luca

    2015-01-01

    . aeruginosa O12 OSA gene cluster, an antibiotic resistance determinant (gyrAC248T), and other genes that have been transferred between P. aeruginosa strains with distinct core genome architectures. We showed that these genes were likely acquired from an O12 serotype strain that is closely related to P...... in clinical settings and outbreaks. These serotype O12 isolates exhibit high levels of resistance to various classes of antibiotics. Here, we explore how the P. aeruginosa OSA biosynthesis gene clusters evolve in the population by investigating the association between the phylogenetic relationships among 83 P....... aeruginosa strains and their serotypes. While most serotypes were closely linked to the core genome phylogeny, we observed horizontal exchange of OSA biosynthesis genes among phylogenetically distinct P. aeruginosa strains. Specifically, we identified a "serotype island" ranging from 62 kb to 185 kb containing the P...

  20. Serotype determination of Salmonella by xTAG assay.

    Science.gov (United States)

    Zheng, Zhibei; Zheng, Wei; Wang, Haoqiu; Pan, Jincao; Pu, Xiaoying

    2017-10-01

    Currently, no protocols or commercial kits are available to determine the serotypes of Salmonella by using Luminex MAGPIX®. In this study, an xTAG assay for serotype determination of Salmonella suitable for Luminex MAGPIX® is described and 228 Salmonella isolates were serotype determined by this xTAG assay. The xTAG assay consists of two steps: 1) Multiplex PCR to amplify simultaneously O, H and Vi antigen genes of Salmonella, and 2) Magplex-TAG™ microsphere hybridization to identify accurately the specific PCR products of different antigens. Compared with the serotyping results of traditional serum agglutination test, the sensitivity and specificity of the xTAG assay were 95.1% and 100%, respectively. The agreement rate of these two assays was 95.2%. Compared with Luminex xMAP® Salmonella Serotyping Assay (SSA) kit, the advantages of this xTAG assay are: First, the magnetic beads make it applicable to both the Luminex®100/200™ and MAGPIX® systems. Second, only primers rather than both primers and probes are needed in the xTAG assay, and the process of coupling antigen-specific oligonucleotide probes to beads is circumvented, which make the xTAG assay convenient to be utilized by other laboratories. The xTAG assay may serve as a rapid alternative or complementary method for traditional Salmonella serotyping tests, especially for laboratories that utilize the MAGPIX® systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. A comparison of machine learning and Bayesian modelling for molecular serotyping.

    Science.gov (United States)

    Newton, Richard; Wernisch, Lorenz

    2017-08-11

    Streptococcus pneumoniae is a human pathogen that is a major cause of infant mortality. Identifying the pneumococcal serotype is an important step in monitoring the impact of vaccines used to protect against disease. Genomic microarrays provide an effective method for molecular serotyping. Previously we developed an empirical Bayesian model for the classification of serotypes from a molecular serotyping array. With only few samples available, a model driven approach was the only option. In the meanwhile, several thousand samples have been made available to us, providing an opportunity to investigate serotype classification by machine learning methods, which could complement the Bayesian model. We compare the performance of the original Bayesian model with two machine learning algorithms: Gradient Boosting Machines and Random Forests. We present our results as an example of a generic strategy whereby a preliminary probabilistic model is complemented or replaced by a machine learning classifier once enough data are available. Despite the availability of thousands of serotyping arrays, a problem encountered when applying machine learning methods is the lack of training data containing mixtures of serotypes; due to the large number of possible combinations. Most of the available training data comprises samples with only a single serotype. To overcome the lack of training data we implemented an iterative analysis, creating artificial training data of serotype mixtures by combining raw data from single serotype arrays. With the enhanced training set the machine learning algorithms out perform the original Bayesian model. However, for serotypes currently lacking sufficient training data the best performing implementation was a combination of the results of the Bayesian Model and the Gradient Boosting Machine. As well as being an effective method for classifying biological data, machine learning can also be used as an efficient method for revealing subtle biological

  2. Using polysaccharides against cancer

    Directory of Open Access Journals (Sweden)

    E. Azarnoosh

    2017-11-01

    Full Text Available Background and objectives: Nowadays cancer is one of the most important concerns of the society. The adverse effects of common therapeutics and resistance of some cancerous cells to treatment have brought the necessity of new approaches towards the issue. Polysaccharides are a group of carbohydrates found in natural sources. In the present article, our goal was to show the positive effects of carbohydrates (especially polysaccharides in cancer treatment, based on literature review. Methods: The literature review was carried out between 1990 and 2017 inclusive using the following search terms: cancer, carbohydrate and polysaccharide and was performed with use of Google scholar, Medline, Scopus, PubMed, Elsevier and other similar data banks, related to medicine and pharmaceutical fields. Results: Plants like Lyceum barbarum, Astragalus membrannceous, Panax ginseng, and Antrodia camphorate have been studied with promising effects in combating cancerous cells. The polysaccharides from these plants have benefits with numerous mechanisms such as apoptosis, inhibition of angiogenesis, anti-proliferation, immunomodulation, tumor suppression, and increase in macrophage activity. Other studies showed over 200 mushrooms with anticancer effects, especially basidiomycetes (e.g. Ganoderma lucidum. Sulfated polysaccharides found in sea and animals or even a few bacteria like E. coli showed to be useful in cancer. Conclusion: Scientists are realizing the importance of natural drugs and polysaccharide as good and available sources that could give a bright future for prevention, cure and palliative therapy in cancer.

  3. PCR specific for Actinobacillus pleuropneumoniae serotype 3

    DEFF Research Database (Denmark)

    Zhou, L.; Jones, S.C.P.; Angen, Øystein

    2008-01-01

    , but the method has liminations, for example, cross-reactions between serotypes 3, 6, and 8. This study describes the development of a serotype 3-specific PCR, based on the capsule locus, which can be used in a multiplex format with the organism's specific gene apxIV. The PCR test was evaluated on 266 strains...

  4. Antioxidant effects of polysaccharides from traditional Chinese medicines.

    Science.gov (United States)

    Liu, Yang; Huang, Gangliang

    2017-12-07

    Polysaccharides 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 polysaccharides were reviewed. The polysaccharides contain plant polysaccharides, animal polysaccharides and microbial polysaccharides. 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.

  5. Polysaccharide-Based Micelles for Drug Delivery

    Directory of Open Access Journals (Sweden)

    Nan Zhang

    2013-05-01

    Full Text Available Delivery of hydrophobic molecules and proteins has been an issue due to poor bioavailability following administration. Thus, micelle carrier systems are being investigated to improve drug solubility and stability. Due to problems with toxicity and immunogenicity, natural polysaccharides are being explored as substitutes for synthetic polymers in the development of new micelle systems. By grafting hydrophobic moieties to the polysaccharide backbone, self-assembled micelles can be readily formed in aqueous solution. Many polysaccharides also possess inherent bioactivity that can facilitate mucoadhesion, enhanced targeting of specific tissues, and a reduction in the inflammatory response. Furthermore, the hydrophilic nature of some polysaccharides can be exploited to enhance circulatory stability. This review will highlight the advantages of polysaccharide use in the development of drug delivery systems and will provide an overview of the polysaccharide-based micelles that have been developed to date.

  6. Antimicrobial effect of a crude sulfated polysaccharide from the red seaweed Gracilaria ornata

    Directory of Open Access Journals (Sweden)

    Rodrigo das Neves dos Santos Amorim

    2012-04-01

    Full Text Available The aim of this study was to determine the yield, chemical composition, specific rotation (SR, infrared (IR spectroscopy and the effect on bacterial growth of a crude sulfated polysaccharide (SP from the red marine alga G. ornata (Go. Go-1 (25°C, Go-2 (80°C, and Go-3 (80°C were sequentially extracted and yielded 9.2%. The contents of sulfate (5.88-10.3% and proteins (0.1-3.7% were small. The values of SR were [µ]D20°f -19.0, -51.0, and -56.5, respectively. IR spectrums showed the presence of galactose-4 sulfate and absence of 3,6-anydrogalactose-2 sulfate, galactose-6 sulfate and galactose-2 sulfate. SR and IR techniques confirmed SPs. Go-3 was tested on the growth of bacteria (Bacillus subtilis, Staphylococcus aureus, Enterobacter aerogens, Escherichia coli, Pseudomonas aeruginosa, Salmonela choleraesuis and Salmonela typhi, but only E. coli was inhibited.

  7. Spatial pattern of foot-and-mouth disease virus serotypes in North Central Nigeria

    Directory of Open Access Journals (Sweden)

    Yiltawe Simwal Wungak

    2017-04-01

    Full Text Available Aim: This study aimed to determine the foot-and-mouth disease virus (FMDV serotypes circulating, the prevalence of FMDV serotypes, and the spatial distribution of FMDV among sedentary and pastoral cattle herds in the North-Central Nigeria. Materials and Methods: A cross-sectional study was undertaken, during which a total of 155 sera that tested positive for foot-and-mouth disease (FMD 3ABC non-structural protein antibodies were selected and screened for FMD structural protein serotypes, A, O, SAT 1, and SAT 2 using a solid-phase competitive enzyme-linked immunosorbent assay (ELISA. Epithelial tissue specimens were collected during outbreak investigations which were tested for FMD using an antigen capture ELISA for serotype A, O, SAT 1, and SAT 2. Results: An overall serotype-specific prevalence of 79.35 (95% confidence interval [CI]: 72.4-85.18 was recorded for serotype O, 65.2% (95% CI: 57.41-72.3 for serotype A, 52.9% (95% CI: 45.03-60.67 for SAT-2, and 33.55% (95% CI: 26.45-41.26 for SAT-1. Evidence of exposure to multiple FMDV serotypes showed that 12.26% of the sera samples had antibodies against four serotypes circulating, 30.97% had antibodies against three serotypes circulating, 22.58% had antibodies against two serotypes, and 17% showed exposure to only one serotype. Clinical specimens (epithelial tissue collected during outbreak investigations showed that serotype O has the highest proportion of 50% with serotype A - 25%; SAT 2 - 20.8%; and SAT 1 - 4.1%. Conclusion: The study detected diffuse and co-circulation of serotypes A, O, SAT1, and SAT2 within the study area, and hence the need for the appropriately matched multivalent vaccine is strongly advocated for FMD control in Nigeria.

  8. Immunosuppressive drugs impairs antibody response of the polysaccharide and conjugated pneumococcal vaccines in patients with Crohn's disease

    DEFF Research Database (Denmark)

    Kantsø, Bjørn; Halkjær, Sofie Ingdam; Thomsen, Ole Østergaard

    2015-01-01

    BACKGROUND: Patients with Crohn's disease (CD) have a higher risk of infectious diseases including pneumococcal infections, and the risk increases with immunotherapy. The primary endpoint of this study was to investigate the specific antibody response to two pneumococcal vaccines in CD patients...... with and without immunosuppressive treatment four weeks post vaccination. METHODS: In a randomized trial of the 23-valent pneumococcal polysaccharide vaccine (PPV23) and the 13-valent pneumococcal conjugated vaccine (PCV13), a group of CD patients treated with immunosuppressive drugs (IS) alone or in combination...... with TNF-α antagonists were compared to a group of CD patients not treated with any of these drugs (untreated). Specific pneumococcal antibody concentrations were measured against 12 serotypes common to the two vaccines before and 4 week after vaccination. RESULTS: PCV13 induced a significantly higher...

  9. The astrophysical S-factor of the direct 18O(p, γ)19F capture by the ANC method

    Science.gov (United States)

    Burjan, V.; Hons, Z.; Kroha, V.; Mrázek, J.; Piskoř, Š.; Mukhamedzhanov, A. M.; Trache, L.; Tribble, R. E.; La Cognata, M.; Lamia, L.; Pizzone, G. R.; Romano, S.; Spitaleri, C.; Tumino, A.

    2018-01-01

    We attempted to determine the astrophysical S-factor of the direct part of the 18O(p, γ)19F capture by the indirect method of asymptotic normalization coefficients (ANC). We measured the differential cross section of the transfer reaction 18O(3He, d)19F at a 3He energy of 24.6 MeV. The measurement was realized on the cyclotron of the NPI in Řež, Czech Republic, with the gas target consisting of the high purity 18O (99.9 %). The reaction products were measured by eight ΔE-E telescopes composed from thin and thick silicon surface-barrier detectors. The parameters of the optical model for the input channel were deduced by means of the code ECIS and the analysis of transfer reactions to 12 levels of the 19F nucleus up to 8.014 MeV was made by the code FRESCO. The deduced ANCs were then used to specify the direct contribution to the 18O(p, γ)19F capture process and were compared with the mutually different results of two works.

  10. Correlation of Serotype-Specific Dengue Virus Infection with Clinical Manifestations

    Science.gov (United States)

    Halsey, Eric S.; Marks, Morgan A.; Gotuzzo, Eduardo; Fiestas, Victor; Suarez, Luis; Vargas, Jorge; Aguayo, Nicolas; Madrid, Cesar; Vimos, Carlos; Kochel, Tadeusz J.; Laguna-Torres, V. Alberto

    2012-01-01

    Background Disease caused by the dengue virus (DENV) is a significant cause of morbidity throughout the world. Although prior research has focused on the association of specific DENV serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) with the development of severe outcomes such as dengue hemorrhagic fever and dengue shock syndrome, relatively little work has correlated other clinical manifestations with a particular DENV serotype. The goal of this study was to estimate and compare the prevalence of non-hemorrhagic clinical manifestations of DENV infection by serotype. Methodology and Principal Findings Between the years 2005–2010, individuals with febrile disease from Peru, Bolivia, Ecuador, and Paraguay were enrolled in an outpatient passive surveillance study. Detailed information regarding clinical signs and symptoms, as well as demographic information, was collected. DENV infection was confirmed in patient sera with polyclonal antibodies in a culture-based immunofluorescence assay, and the infecting serotype was determined by serotype-specific monoclonal antibodies. Differences in the prevalence of individual and organ-system manifestations were compared across DENV serotypes. One thousand seven hundred and sixteen individuals were identified as being infected with DENV-1 (39.8%), DENV-2 (4.3%), DENV-3 (41.5%), or DENV-4 (14.4%). When all four DENV serotypes were compared with each other, individuals infected with DENV-3 had a higher prevalence of musculoskeletal and gastrointestinal manifestations, and individuals infected with DENV-4 had a higher prevalence of respiratory and cutaneous manifestations. Conclusions/Significance Specific clinical manifestations, as well as groups of clinical manifestations, are often overrepresented by an individual DENV serotype. PMID:22563516

  11. Correlation of serotype-specific dengue virus infection with clinical manifestations.

    Directory of Open Access Journals (Sweden)

    Eric S Halsey

    Full Text Available Disease caused by the dengue virus (DENV is a significant cause of morbidity throughout the world. Although prior research has focused on the association of specific DENV serotypes (DENV-1, DENV-2, DENV-3, and DENV-4 with the development of severe outcomes such as dengue hemorrhagic fever and dengue shock syndrome, relatively little work has correlated other clinical manifestations with a particular DENV serotype. The goal of this study was to estimate and compare the prevalence of non-hemorrhagic clinical manifestations of DENV infection by serotype.Between the years 2005-2010, individuals with febrile disease from Peru, Bolivia, Ecuador, and Paraguay were enrolled in an outpatient passive surveillance study. Detailed information regarding clinical signs and symptoms, as well as demographic information, was collected. DENV infection was confirmed in patient sera with polyclonal antibodies in a culture-based immunofluorescence assay, and the infecting serotype was determined by serotype-specific monoclonal antibodies. Differences in the prevalence of individual and organ-system manifestations were compared across DENV serotypes. One thousand seven hundred and sixteen individuals were identified as being infected with DENV-1 (39.8%, DENV-2 (4.3%, DENV-3 (41.5%, or DENV-4 (14.4%. When all four DENV serotypes were compared with each other, individuals infected with DENV-3 had a higher prevalence of musculoskeletal and gastrointestinal manifestations, and individuals infected with DENV-4 had a higher prevalence of respiratory and cutaneous manifestations.Specific clinical manifestations, as well as groups of clinical manifestations, are often overrepresented by an individual DENV serotype.

  12. (19)F-heptuloses as tools for the non-invasive imaging of GLUT2-expressing cells

    DEFF Research Database (Denmark)

    Malaisse, Willy J; Zhang, Ying; Louchami, Karim

    2012-01-01

    Suitable analogs of d-mannoheptulose are currently considered as possible tools for the non-invasive imaging of pancreatic islet insulin-producing cells. Here, we examined whether (19)F-heptuloses could be used for non-invasive imaging of GLUT2-expressing cells. After 20 min incubation, the uptake......-mannoheptulose in inhibiting insulin release. The 1-deoxy-1-fluoro-d-mannoheptulose and 3-deoxy-3-fluoro-d-mannoheptulose only marginally affected INS-1 cell viability. These findings are compatible with the view that selected (19)F-heptuloses may represent suitable tools for the non-invasive imaging of hepatocytes...

  13. 19F-MRI of stomach and intestine using 50% FTPA emulsion under 2T MRI system

    International Nuclear Information System (INIS)

    Shimizu, Masahiro; Kobayashi, Teturou; Mishima, Hideyuki

    1991-01-01

    1 H-MRI is of clinical value in many lesions, but imaging of gastrointestinal lesions is still difficult by 1 H-MRI. To overcome this weak point of 1 H-MRI, rabbit stomachs were examined by 19 F-MRI using 50% FTPA emulsion. We also examined the stability of 50% FTPA emulsion in the stomach and its absorption from the gastrointestinal tract. We found that 50% FTPA emulsion was very stable at pH 1.5, and only a very small amount was absorbed. A rabbit (weighing 2 kg) was anesthetized, and 100 ml of 50% FTPA emulsion was infused into the stomach by catheter. 19 F-MRI was performed in this rabbit using a 2 T superconducting MRI system designed for human use, and clear pictures of the stomach were obtained. From our results we conclude that 19 F-MRI of the stomach using 50% FTPA emulsion is of practical value. (author)

  14. Genomic Evolution Of The Mdr Serotype O12 Pseudomonas Aeruginosa Clone

    DEFF Research Database (Denmark)

    Thrane, Sandra Wingaard; Taylor, Véronique L.; Freschi, Luca

    2015-01-01

    that serotype switching in combination with an antibiotic resistance determinant contributed to the dissemination of the O12 serotype in the clinic. This selective advantage coincides with the introduction of fluoroquinolones in the clinic. With the PAst program isolates can be serotyped using WGS data......Introduction: Since the 1980’s the serotype O12 of Pseudomonas aeruginosa has emerged as the predominant serotype in clinical settings and in epidemic outbreaks. These serotype O12 isolates exhibit high levels of resistance to various classes of antibiotics.Methods: In this study, we explore how......).Results: While most serotypes were closely linked to the core genome phylogeny we observed horizontal exchange of LPS genes among distinct P. aeruginosa strains. Specifically, we identified a ‘serotype island’ containing the P. aeruginosa O12 LPS gene cluster and an antibiotic resistance determinant (gyrAC248T...

  15. Salmonella serotype distribution in the Dutch broiler supply chain.

    Science.gov (United States)

    van Asselt, E D; Thissen, J T N M; van der Fels-Klerx, H J

    2009-12-01

    Salmonella serotype distribution can give insight in contamination routes and persistence along a production chain. Therefore, it is important to determine not only Salmonella prevalence but also to specify the serotypes involved at the different stages of the supply chain. For this purpose, data from a national monitoring program in the Netherlands were used to estimate the serotype distribution and to determine whether this distribution differs for the available sampling points in the broiler supply chain. Data covered the period from 2002 to 2005, all slaughterhouses (n = 22), and the following 6 sampling points: departure from hatchery, arrival at the farm, departure from the farm, arrival at the slaughterhouse, departure from the slaughterhouse, and end of processing. Furthermore, retail data for 2005 were used for comparison with slaughterhouse data. The following serotypes were followed throughout the chain: Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Paratyphi B var. Java (Salmonella Java), Salmonella Infantis, Salmonella Virchow, and Salmonella Mbandaka. Results showed that serotype distribution varied significantly throughout the supply chain (P supply chain up to the retail phase.

  16. Polysaccharides and their depolymerized fragments from Costaria costata: Molecular weight and sulfation-dependent anticoagulant and FGF/FGFR signal activating activities.

    Science.gov (United States)

    Hou, Ningning; Zhang, Meng; Xu, Yingjie; Sun, Zhongmin; Wang, Jing; Zhang, Lijuan; Zhang, Quanbin

    2017-12-01

    Crude polysaccharides from Costaria costata were extracted by hot water and further fractionated by anion exchange chromatography into three polysaccharide fractions. Three low molecular weight fragments were then prepared by degradation of the polysaccharides with hydrogen peroxide and ascorbic acid. The structural features of the polysaccharides and their low molecular weight fragments were elucidated for the first time based on the HGPC, FT-IR, NMR, MS, monosaccharide composition, and other chemical analyses. Their anticoagulant and FGF-1, -2, -7, -8, -9, -10/FGFR1c signaling activation activities in BaF3 cells were also examined. Our studies showed that the polysaccharides were sulfated at different positions of galactose and fucose residues. The APTT-, PT- and TT-based anticoagulant assay results indicated that a high molecular weight and a higher degree of sulfation were essential for their anticoagulant activities. In contrast, not only the polysaccharides but also the depolymerized fragments showed significant FGF/FGFR signal activating activities in a FGF-, molecular weight-, and sulfation-dependent manner. The results presented in current study demonstrated the potential use of the polysaccharides and their fragments as anticoagulants and FGF signal regulators. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Electron correlation effects on geometries and 19F shieldings of fluorobenzenes

    International Nuclear Information System (INIS)

    Webb, G.A.; Karadakov, P.B.; England, J.A.

    2000-01-01

    In order to include the effects of electron correlation in ab initio molecular orbital calculations it is necessary to go beyond the single determinant Hartree-Fock (HF) level of theory. In the present investigation the influences of both dynamic and non-dynamic correlation effects on the optimised geometries and 19 F nuclear shielding calculations of the twelve fluorobenzenes are reported.The non-dynamic electron correlation effects are represented by complete-active space self-consistent field (CASSCF) calculations. Second- and fourth-order Moller-Plesset (MP2 and MP4) calculations are used to describe the dynamic electron correlation effects. Some density-functional (DFT) results are also reported which do not distinguish between dynamic and non-dynamic electron correlation. Following the correlated geometry optimisations 19 F nuclear shielding calculations were performed using the gauge-included atomic orbitals (GIAO) procedure, these were undertaken with wave functions which include various levels of electron correlation including HF, CASSCF and MP2. For the calculations of the optimised geometries, and some of the nuclear shieldings the 6-13G** basis set s used whereas the locally-dense [6-13G** on C and H and 6-311++G(2d,2p) on F] set is used for some of the shielding calculations. A comparison of the results of HF shielding calculations using other basis sets is included. Comparison of the calculated geometry and shielding results with relevant, reported, experimental data is made. (author)

  18. Serotype tracking of Salmonella through integrated broiler chicken operations.

    Science.gov (United States)

    Bailey, J S; Cox, N A; Craven, S E; Cosby, D E

    2002-05-01

    The widespread presence of Salmonella in all phases of broiler chicken production and processing is well documented. However, little information is available to indicate the identity and movement of specific serotypes of Salmonella through the different phases of an integrated operation. In this study, samples were collected from the breeder farm, from the hatchery, from the previous grow-out flock, from the flock during grow-out, and from carcasses after processing. Salmonella were recovered from 6, 98, 24, 60, and 7% of the samples, respectively, in the first trial and from 7, 98, 26, 22, and 36% of the samples, respectively, in the second trial. Seven different serotypes were identified in the first trial, and 12 different serotypes were identified in the second trial. For both trials there was poor correlation between the serotypes found in the breeder farms and those found in the hatchery. This finding and the fact that similar serotypes were found in the hatchery in both trials suggests that there was an endemic population of Salmonella in the hatchery. An association between the serotypes found in the hatchery and those found on the final processed carcasses was observed in both trials. This study confirms that a successful intervention program for broiler production operations must be multifaceted, with one component being disinfection in the hatchery.

  19. Qualitative and quantitative analysis of specific polysaccharides in Dendrobium huoshanense by using saccharide mapping and chromatographic methods.

    Science.gov (United States)

    Deng, Yong; Chen, Ling-Xiao; Han, Bang-Xing; Wu, Ding-Tao; Cheong, Kit-Leong; Chen, Nai-Fu; Zhao, Jing; Li, Shao-Ping

    2016-09-10

    Qualitative and quantitative analysis of specific polysaccharides from ten batches of Dendrobium huoshanense were performed using high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RID), gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR) and saccharide mapping based on polysaccharides analysis by using carbohydrate gel electrophoresis (PACE) and high performance thin layer chromatography (HPTLC). Results showed that molecular weights, the radius of gyrations, and contents of specific polysaccharides in D. huoshanense were ranging from 1.16×10(5) to 2.17×10(5)Da, 38.8 to 52.1nm, and 9.9% to 19.9%, respectively. Furthermore, the main monosaccharide compositions were Man and Glc. Indeed, the main glycosidic linkages were β-1,4-Manp and β-1,4-Glcp, and substituted with acetyl groups at O-2 and O-3 of 1,4-linked Manp. Moreover, results showed that PACE and HPTLC fingerprints of partial acidic and enzymatic hydrolysates of specific polysaccharides were similar, which are helpful to better understand the specific polysaccharides in D. huoshanense and beneficial to improve their quality control. These approaches could also be routinely used for quality control of polysaccharides in other medicinal plants. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Structures of Preferred Human IgV Genes-Based Protective Antibodies Identify How Conserved Residues Contact Diverse Antigens and Assign Source of Specificity to CDR3 Loop Variation.

    Science.gov (United States)

    Bryson, Steve; Thomson, Christy A; Risnes, Louise F; Dasgupta, Somnath; Smith, Kenneth; Schrader, John W; Pai, Emil F

    2016-06-01

    The human Ab response to certain pathogens is oligoclonal, with preferred IgV genes being used more frequently than others. A pair of such preferred genes, IGVK3-11 and IGVH3-30, contributes to the generation of protective Abs directed against the 23F serotype of the pneumonococcal capsular polysaccharide of Streptococcus pneumoniae and against the AD-2S1 peptide of the gB membrane protein of human CMV. Structural analyses of Fab fragments of mAbs 023.102 and pn132p2C05 in complex with portions of the 23F polysaccharide revealed five germline-encoded residues in contact with the key component, l-rhamnose. In the case of the AD-2S1 peptide, the KE5 Fab fragment complex identified nine germline-encoded contact residues. Two of these germline-encoded residues, Arg91L and Trp94L, contact both the l-rhamnose and the AD-2S1 peptide. Comparison of the respective paratopes that bind to carbohydrate and protein reveals that stochastic diversity in both CDR3 loops alone almost exclusively accounts for their divergent specificity. Combined evolutionary pressure by human CMV and the 23F serotype of S. pneumoniae acted on the IGVK3-11 and IGVH3-30 genes as demonstrated by the multiple germline-encoded amino acids that contact both l-rhamnose and AD-2S1 peptide. Copyright © 2016 by The American Association of Immunologists, Inc.

  1. Polysaccharide components from the scape of Musa paradisiaca: main structural features of water-soluble polysaccharide component.

    Science.gov (United States)

    Anjaneyalu, Y V; Jagadish, R L; Raju, T S

    1997-06-01

    Polysaccharide components present in the pseudo-stem (scape) of M. paradisiaca were purified from acetone powder of the scape by delignification followed by extraction with aqueous solvents into water soluble polysaccharide (WSP), EDTA-soluble polysaccharide (EDTA-SP), alkali-soluble polysaccharide (ASP) and alkali-insoluble polysaccharide (AISP) fractions. Sugar compositional analysis showed that WSP and EDTA-SP contained only D-Glc whereas ASP contained D-Glc, L-Ara and D-Xyl in approximately 1:1:10 ratio, respectively, and AISP contained D-Glc, L-Ara and D-Xyl in approximately 10:1:2 ratio, respectively. WSP was further purified by complexation with iso-amylalcohol and characterized by specific rotation, IR spectroscopy, Iodine affinity, ferricyanide number, blue value, hydrolysis with alpha-amylase and glucoamylase, and methylation linkage analysis, and shown to be a amylopectin type alpha-D-glucan.

  2. Electronic stopping powers for fluorine ions in {sup 19}F{sup +}-implanted AgGaS{sub 2} crystal

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xiangdong; Xia Yueyuan; Lu Qingming; Li Feng; Huang Boda

    2004-01-15

    Electronic stopping powers for 80-350 keV {sup 19}F ions in AgGaS{sub 2} were obtained by range measurement. Depth profiles of {sup 19}F in AgGaS{sub 2} were measured by using the {sup 19}F(p,{alpha}{gamma}){sup 16}O resonant nuclear reaction at E{sub R}=872.1 keV. A proper convolution calculation method was used to extract the true distribution of fluorine from the experimental excitation yield curves. The electronic stopping powers were derived through fitting the projected range distributions, simulated by using the TRIM/XLL code, to the experimentally measured range distributions. The electronic stopping cross sections were compared with those obtained from Monte Carlo simulation codes.

  3. First environmental isolation of Cryptococcus gattii serotype B, from Cúcuta, Colombia.

    Science.gov (United States)

    Firacative, Carolina; Torres, Germán; Rodríguez, María Claudia; Escandón, Patricia

    2011-03-01

    In Cúcuta, Cryptococcus gattii serotype B is commonly recovered from immunocompetent patients with cryptococcosis, but it has not been recovered from the environment in spite of its high incidence which is 77% out of reported cases. The aim of this work was to carry out an extensive environmental sampling in Cúcuta, in an attempt to isolate C. gattii serotype B and to expand our knowledge about the ecology and epidemiology of this important yeast. Samples associated with 3,634 trees from 40 zones of Cúcuta were collected and processed with 28 samples collected near the houses of four patients with cryptococcosis caused by C. gattii serotype B. The serotype of the recovered isolates was done using multiplex PCR, molecular patterns were determined by RFLP of the URA5 gene and mating type was determined using the primers MfαU, MfαL, MFa2U and MFa2L. In total, 4,389 samples were processed and one isolate of C. gattii serotype B (VGI/a), two isolates of C. gattii serotype C (VGIII/α) and three isolates of C. neoformans var. grubii, serotype A (VNI/α), were recovered. The density of the recovered isolates varied from 50 to 350 cfu/g of soil. This is the first report on the environmental isolation of C. gattii serotype B from Cúcuta. However, because of the low rate of recovery of isolates from soil only, the environmental niche of C. gattii has not been established and further environmental studies in Cúcuta are necessary, owing that this serotype is not only causing cryptococcosis but also has shown a higher virulence after the Vancouver outbreak.

  4. Advances on Bioactive Polysaccharides from Medicinal Plants.

    Science.gov (United States)

    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.

  5. Association of meningococcal serotypes with the course of disease: serotypes 2a and 2b in the Netherlands, 1959-1981

    NARCIS (Netherlands)

    Spanjaard, L.; Bol, P.; de Marie, S.; Zanen, H. C.

    1987-01-01

    Case histories of 692 patients with meningococcal disease due to serogroup B, C, or W (W-135) were reviewed to study the association of the serotypes 2a and 2b with the course of disease. The case-fatality rate in group B disease was significantly associated with serotype 2b (B:2b) strains (P =

  6. Structural analysis of cell wall polysaccharides using PACE

    Energy Technology Data Exchange (ETDEWEB)

    Mortimer, Jennifer C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint BioEnergy Institute

    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.

  7. Reactogenicity, safety and immunogenicity of a protein-based pneumococcal vaccine in Gambian children aged 2-4 years: A phase II randomized study.

    Science.gov (United States)

    Odutola, A; Ota, M O; Ogundare, E O; Antonio, M; Owiafe, P; Worwui, A; Greenwood, B; Alderson, M; Traskine, M; Verlant, V; Dobbelaere, K; Borys, D

    2016-01-01

    Pneumococcal conjugate vaccines (PCVs) have been successful in preventing invasive pneumococcal disease but effectiveness has been challenged by replacement of vaccine serotypes with non-vaccine serotypes. Vaccines targeting common pneumococcal protein(s) found in most/all pneumococci may overcome this limitation. This phase II study assessed safety and immunogenicity of a new protein-based pneumococcal vaccine containing polysaccharide conjugates of 10 pneumococcal serotypes combined with pneumolysin toxoid(dPly) and pneumococcal histidine triad protein D(PhtD) (PHiD-CV/dPly/PhtD-30) in African children. 120 Gambian children (2-4 years, not previously vaccinated against Streptococcus pneumoniae) randomized (1:1) received a single dose of PHiD-CV/dPly/PhtD-30 or PCV13. Adverse events occurring over 4 d post-vaccination were reported, and blood samples obtained pre- and 1-month post-vaccination. Serious adverse events were reported for 6 months post-vaccination. Solicited local and systemic adverse events were reported at similar frequency in each group. One child (PHiD-CV/dPly/PhtD-30 group) reported a grade 3 local reaction to vaccination. Haematological and biochemical parameters seemed similar pre- and 1-month post-vaccination in each group. High pre-vaccination Ply and PhtD antibody concentrations were observed in each group, but only increased in PHiD-CV/dPly/PhtD-30 vaccinees one month post-vaccination. One month post-vaccination, for each vaccine serotype ≥96.2% of PHiD-CV/dPly/PhtD-30 vaccinees had serotype-specific polysaccharide antibody concentrations ≥0.20µg/mL except serotypes 6B (80.8%) and 23F (65.4%), and ≥94.1% had OPA titres of ≥8 except serotypes 1 (51.9%), 5 (38.5%) and 6B (78.0%), within ranges seen in PCV13-vaccinated children. A single dose of PHiD-CV/dPly/PhtD-30 vaccine, administered to Gambian children aged 2-4 y not previously vaccinated with a pneumococcal vaccine, was well-tolerated and immunogenic.

  8. An exocellular polysaccharide and its interactions with proteins

    NARCIS (Netherlands)

    Tuinier, R.

    1999-01-01

    In the food industry polysaccharides are used as thickening or gelling agents. Polysaccharides are usually extracted from plants. Micro-organisms are also capable of excreting polysaccharides: exocellular polysaccharides (EPSs). In some cases EPSs are produced in-situ in food products,

  9. Nasopharyngeal Carriage of Streptococcus Pneumoniae and Serotypes Indentified among Nursing Home Residents in Comparison to the Elderly and Patients Younger than 65 Years Living in Domestic Environment.

    Science.gov (United States)

    Kolšek-Šušteršič, Maja; Beg Krasnič, Andreja; Mioč, Verica; Paragi, Metka; Rifel, Janez

    2017-09-01

    In Slovenia, there is little data available on pneumococcal vaccination rates and no data on asymptomatic NPCR and serotypes in the population of nursing home residents in comparison to the elderly living in domestic environment, therefore the goal was to gain these data. A cross sectional epidemiological study was performed. Nasopharyngeal swabs from 151 nursing home residents, 150 elderly living in domestic environment, and 38 adults less than 65 years old were collected twice (in two consecutive years). The swabs were analysed for pneumococcal identification and serotyping. Patient data were collected from medical files and medical history. No statistically significant differences in NPCR were seen between compared groups in two consecutive years. An average NPCR in two consecutive years in nursing home residents was 1.45%, in the elderly living in domestic environment 0.85%, and in adults less than 65 years old 7.05%. Serotypes identified among nursing home residents were 6B and 9N, among the group of elderly living in domestic environment, 6A and among adults less than 65 years old, 35F, 18C and 3. Pneumococcal vaccination rates were low (3.3% in nursing home residents, 6% in the elderly from domestic environment and 0% in the group of adults less than 65 years old). Our data suggests that NPCR and the proportion of people vaccinated with pneumococcal vaccine among the elderly are low. We identified different serotypes in all groups, only one person was a chronic carrier (serotype 35F).

  10. Three-dimensional structure of Wza, the protein required for translocation of group 1 capsular polysaccharide across the outer membrane of Escherichia coli.

    Science.gov (United States)

    Beis, Konstantinos; Collins, Richard F; Ford, Robert C; Kamis, Alhaji B; Whitfield, Chris; Naismith, James H

    2004-07-02

    Wza is a highly conserved multimeric outer membrane protein complex required for the surface expression of the serotype K30 group 1 capsular polysaccharide in Escherichia coli. Here we present the first three-dimensional structure of this type of polysaccharide exporter at a 15.5-A resolution obtained using single particle averaging on a dataset of cryo-negatively stained protein. Previous structural studies on purified Wza have revealed a homo-oligomeric ring structure that is most probably composed of eight subunits. Symmetry analysis of the three-dimensional structure combined with biochemical two- and three-dimensional crystallographic data strongly suggest that Wza is an octameric complex with a C4 quasi-rotational symmetry and is organized as a tetramer of dimeric subunits. Wza is best described as a stack of two 4-A high rings with differing diameters providing a mushroom-like aspect from the side. The larger ring has a distinctive square shape with a diameter of 115 A, whereas the smaller is almost circular with a diameter of 90 A. In the center of the complex and enclosed by the four symmetrical arms is a small elliptical cagelike cavity of approximately 40 A in diameter. The central cavity is effectively sealed at the top and bottom of the complex but has small inter-arm holes when viewed from the side. We discuss the structure of this complex and implications in the surface translocation of cell-surface polysaccharide.

  11. Three-Dimensional Structural Aspects of Protein–Polysaccharide Interactions

    Directory of Open Access Journals (Sweden)

    Masamichi Nagae

    2014-03-01

    Full Text Available Linear polysaccharides are typically composed of repeating mono- or disaccharide units and are ubiquitous among living organisms. Polysaccharide diversity arises from chain-length variation, branching, and additional modifications. Structural diversity is associated with various physiological functions, which are often regulated by cognate polysaccharide-binding proteins. Proteins that interact with linear polysaccharides have been identified or developed, such as galectins and polysaccharide-specific antibodies, respectively. Currently, data is accumulating on the three-dimensional structure of polysaccharide-binding proteins. These proteins are classified into two types: exo-type and endo-type. The former group specifically interacts with the terminal units of polysaccharides, whereas the latter with internal units. In this review, we describe the structural aspects of exo-type and endo-type protein-polysaccharide interactions. Further, we discuss the structural basis for affinity and specificity enhancement in the face of inherently weak binding interactions.

  12. The combined application of {sup 1}H MRI and {sup 19}F MRS to the study of cerebroprotection

    Energy Technology Data Exchange (ETDEWEB)

    Haga, K.K

    2000-07-01

    The research presented in this thesis focuses on the application of {sup 1}H and {sup 19}F nuclear magnetic resonance techniques to the evaluation of the neuroprotective and pharmacokinetic properties of a novel, nitric oxide synthase inhibitor in a rat model of stroke. Although there is a growing body of research on the application of {sup 19}F magnetic resonance spectroscopy techniques to the study of psychotropic agents, this is the first attempt to apply these methods to the evaluation of an agent being developed for cerebroprotection. TRIM, 1-(2-trifluoromethylphenyl) imidazole, is a selective inhibitor of the neuronal form of nitric oxide synthase in the rat and mouse brain. The first portion of this thesis demonstrates TRIM's neuroprotective properties when administered post-occlusion in the middle cerebral artery occlusion model of focal cerebral ischaemia. In addition, these neuroprotective effects may be eliminated by the co-administration of L-arginine, a nitric oxide precursor, indicating a role for neuronal nitric oxide synthase in ischaemic damage. {sup 1}H magnetic resonance imaging at 24 hours post-occlusion indicates a 40% reduction in lesion volume following TRIM administration as compared to the saline control group. The second part of this thesis pertains to the development and application of {sup 19}F MRS methods, in vivo and in vitro, to enable the investigator to monitor and quantify TRIM in the rat CNS pre and post-occlusion. In this section, {sup 19}F MRS studies were conducted to measure the in vivo T{sub 1} and T{sub 2} relaxation parameters and subsequently, the concentration of TRIM achieved in the rat CNS over an 8 hour measuring period. From this data, the in vivo pharmacokinetics of TRIM were evaluated and applied to the neuroprotective strategy in cerebral ischaemia. In vitro measurements of TRIM concentrations in the rat CNS were compared to the in vivo concentration calculations to evaluate the reliability of TRIM

  13. Photoproton cross section for /sup 19/F

    Energy Technology Data Exchange (ETDEWEB)

    Tsubota, H [Tohoku Univ., Sendai (Japan). Coll. of General Education; Kawamura, N; Oikawa, S; Uegaki, J I

    1975-02-01

    Proton energy spectra have been measured at 90/sup 0/ for the /sup 19/F(e,e'p)/sup 18/O reaction in the giant resonance region. The (..gamma..,p/sub 0/) and (..gamma..,p/sub 1/) differential cross sections are extracted from the proton energy spectra by using virtual-photon spectra. The integrated differential cross section of the (..gamma..,p/sub 0/) and (..gamma..,p/sub 1/) reactions are 1.80+-0.27 and 0.50+-0.45 MeV-mb/sr, respectively. The results are discussed with the shell model theory by comparing with the (..gamma..,p/sub 0/) cross section of the neighboring 4n-nucleus /sup 20/Ne. A significant increase of the proton yield leaving the non-ground states is found at 25 MeV of the incident electron energy. This is discussed in terms of the core excitation effect.

  14. Tanks 18 And 19-F Structural Flowable Grout Fill Material Evaluation And Recommendations

    International Nuclear Information System (INIS)

    Langton, C. A.; Stefanko, D. B.

    2013-01-01

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: 1) physically stabilize the final landfill by filling the empty volume in the tanks with a non-compressible material; 2) provide a barrier for inadvertent intrusion into the tank; 3) reduce contaminant mobility by a) limiting the hydraulic conductivity of the closed tank and b) reducing contact between the residual waste and infiltrating water; and 4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: 1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). 2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. 3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix design. 4

  15. Tanks 18 And 19-F Structural Flowable Grout Fill Material Evaluation And Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C. A.; Stefanko, D. B.

    2013-04-23

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: 1) physically stabilize the final landfill by filling the empty volume in the tanks with a non-compressible material; 2) provide a barrier for inadvertent intrusion into the tank; 3) reduce contaminant mobility by a) limiting the hydraulic conductivity of the closed tank and b) reducing contact between the residual waste and infiltrating water; and 4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: 1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). 2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. 3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix design. 4

  16. 2H{ 19F} REDOR for distance measurements in biological solids using a double resonance spectrometer

    Science.gov (United States)

    Grage, Stephan L.; Watts, Jude A.; Watts, Anthony

    2004-01-01

    A new approach for distance measurements in biological solids employing 2H{ 19F} rotational echo double resonance was developed and validated on 2H, 19F- D-alanine and an imidazopyridine based inhibitor of the gastric H +/K +-ATPase. The 2H- 19F double resonance experiments presented here were performed without 1H decoupling using a double resonance NMR spectrometer. In this way, it was possible to benefit from the relatively longer distance range of fluorine without the need of specialized fluorine equipment. A distance of 2.5 ± 0.3 Å was measured in the alanine derivative, indicating a gauche conformation of the two labels. In the case of the imidazopyridine compound a lower distance limit of 5.2 Å was determined and is in agreement with an extended conformation of the inhibitor. Several REDOR variants were compared, and their advantages and limitations discussed. Composite fluorine dephasing pulses were found to enhance the frequency bandwidth significantly, and to reduce the dependence of the performance of the experiment on the exact choice of the transmitter frequency.

  17. Exposure of a 23F Serotype Strain of Streptococcus pneumoniae to Cigarette Smoke Condensate Is Associated with Selective Upregulation of Genes Encoding the Two-Component Regulatory System 11 (TCS11

    Directory of Open Access Journals (Sweden)

    Riana Cockeran

    2014-01-01

    Full Text Available Alterations in whole genome expression profiles following exposure of the pneumococcus (strain 172, serotype 23F to cigarette smoke condensate (160 μg/mL for 15 and 60 min have been determined using the TIGR4 DNA microarray chip. Exposure to CSC resulted in the significant (P<0.014–0.0006 upregulation of the genes encoding the two-component regulatory system 11 (TCS11, consisting of the sensor kinase, hk11, and its cognate response regulator, rr11, in the setting of increased biofilm formation. These effects of cigarette smoke on the pneumococcus may contribute to colonization of the airways by this microbial pathogen.

  18. Two dimensional NMR studies of polysaccharides

    International Nuclear Information System (INIS)

    Byrd, R.A.; Egan, W.; Summers, M.F.

    1987-01-01

    Polysaccharides are very important components in the immune response system. Capsular polysaccharides and lipopolysaccharides occupy cell surface sites of bacteria, play key roles in recognition and some have been used to develop vaccines. Consequently, the ability to determine chemical structures of these systems is vital to an understanding of their immunogenic action. The authors have been utilizing recently developed two-dimensional homonuclear and heteronuclear correlation spectroscopy for unambiguous assignment and structure determination of a number of polysaccharides. In particular, the 1 H-detected heteronuclear correlation experiments are essential to the rapid and sensitive determination of these structures. Linkage sites are determined by independent polarization transfer experiments and multiple quantum correlation experiments. These methods permit the complete structure determination on very small amounts of the polysaccharides. They present the results of a number of structural determinations and discuss the limits of these experiments in terms of their applications to polysaccharides

  19. Botanical polysaccharides: macrophage immunomodulation and therapeutic potential.

    Science.gov (United States)

    Schepetkin, Igor A; Quinn, Mark T

    2006-03-01

    Botanical polysaccharides exhibit a number of beneficial therapeutic properties, and it is thought that the mechanisms involved in these effects are due to the modulation of innate immunity and, more specifically, macrophage function. In this review, we summarize our current state of understanding of the macrophage modulatory effects of botanical polysaccharides isolated from a wide array of different species of flora, including higher plants, mushrooms, lichens and algae. Overall, the primary effect of botanical polysaccharides is to enhance and/or activate macrophage immune responses, leading to immunomodulation, anti-tumor activity, wound-healing and other therapeutic effects. Furthermore, botanical and microbial polysaccharides bind to common surface receptors and induce similar immunomodulatory responses in macrophages, suggesting that evolutionarily conserved polysaccharide structural features are shared between these organisms. Thus, the evaluation of botanical polysaccharides provides a unique opportunity for the discovery of novel therapeutic agents and adjuvants that exhibit beneficial immunomodulatory properties.

  20. In vitro fermentation of mulberry fruit polysaccharides by human fecal inocula and impact on microbiota.

    Science.gov (United States)

    Chen, Chun; Huang, Qiang; Fu, Xiong; Liu, Rui Hai

    2016-11-09

    This study investigated the in vitro fermentation of polysaccharides from Morus alba L., the contribution of its carbohydrates to the fermentation, and the effect on the composition of gut microbiota. Over 48 h of fermentation, the pH value in the fecal culture decreased from 7.12 to 6.14, and the total short chain fatty acids (SCFA) and acetic, propionic, and butyric acids all significantly increased. After 48 h of fermentation, 45.36 ± 1.36% of the total carbohydrates in the polysaccharide, including 35.72 ± 1.51% of arabinose, 23.1 ± 1.19% of galactose, 41.43 ± 1.52% of glucose, 26.36 ± 1.93% of rhamnose and 65.57 ± 1.07% of galacturic acid, were consumed. The increase in acetic and butyric acids was primarily due to the fermentation of galactose and galacturonic acid in the polysaccharide, while the increase in propionic acid resulted mainly from the fermentation of arabinose and glucose. In addition, the polysaccharide could modulate the gut microbiota composition by increasing the Bacteroidetes population and decreasing the Firmicutes population. The results may facilitate the development of food products known as prebiotics, aimed at improving gastrointestinal health.

  1. Probe-Specific Procedure to Estimate Sensitivity and Detection Limits for 19F Magnetic Resonance Imaging.

    Directory of Open Access Journals (Sweden)

    Alexander J Taylor

    Full Text Available Due to low fluorine background signal in vivo, 19F is a good marker to study the fate of exogenous molecules by magnetic resonance imaging (MRI using equilibrium nuclear spin polarization schemes. Since 19F MRI applications require high sensitivity, it can be important to assess experimental feasibility during the design stage already by estimating the minimum detectable fluorine concentration. Here we propose a simple method for the calibration of MRI hardware, providing sensitivity estimates for a given scanner and coil configuration. An experimental "calibration factor" to account for variations in coil configuration and hardware set-up is specified. Once it has been determined in a calibration experiment, the sensitivity of an experiment or, alternatively, the minimum number of required spins or the minimum marker concentration can be estimated without the need for a pilot experiment. The definition of this calibration factor is derived based on standard equations for the sensitivity in magnetic resonance, yet the method is not restricted by the limited validity of these equations, since additional instrument-dependent factors are implicitly included during calibration. The method is demonstrated using MR spectroscopy and imaging experiments with different 19F samples, both paramagnetically and susceptibility broadened, to approximate a range of realistic environments.

  2. Probe-Specific Procedure to Estimate Sensitivity and Detection Limits for 19F Magnetic Resonance Imaging.

    Science.gov (United States)

    Taylor, Alexander J; Granwehr, Josef; Lesbats, Clémentine; Krupa, James L; Six, Joseph S; Pavlovskaya, Galina E; Thomas, Neil R; Auer, Dorothee P; Meersmann, Thomas; Faas, Henryk M

    2016-01-01

    Due to low fluorine background signal in vivo, 19F is a good marker to study the fate of exogenous molecules by magnetic resonance imaging (MRI) using equilibrium nuclear spin polarization schemes. Since 19F MRI applications require high sensitivity, it can be important to assess experimental feasibility during the design stage already by estimating the minimum detectable fluorine concentration. Here we propose a simple method for the calibration of MRI hardware, providing sensitivity estimates for a given scanner and coil configuration. An experimental "calibration factor" to account for variations in coil configuration and hardware set-up is specified. Once it has been determined in a calibration experiment, the sensitivity of an experiment or, alternatively, the minimum number of required spins or the minimum marker concentration can be estimated without the need for a pilot experiment. The definition of this calibration factor is derived based on standard equations for the sensitivity in magnetic resonance, yet the method is not restricted by the limited validity of these equations, since additional instrument-dependent factors are implicitly included during calibration. The method is demonstrated using MR spectroscopy and imaging experiments with different 19F samples, both paramagnetically and susceptibility broadened, to approximate a range of realistic environments.

  3. Lung abscess caused by Streptococcus pneumoniae serotype 6B.

    Science.gov (United States)

    Ito, Yuhei; Toyoshima, Hirokazu; Suzuki, Takehiro; Iwamoto, Keisuke; Sasano, Hajime; Itani, Hidetoshi; Kondo, Shigeto; Tanigawa, Motoaki

    2018-01-01

    Lung abscess has been considered to be a rare complication of pneumococcal infection, and most cases are reported to be Streptococcus pneumoniae serotype 3. A 67-year-old man presented with fever and was diagnosed to have lung abscess caused by S. pneumoniae serotype 6B. The minimal inhibitory concentration (MIC) of penicillin for the isolate was 1 μg/mL. He was treated with high-dose intravenous sulbactam/ampicillin as definitive therapy based on susceptibility testing for S. pneumoniae and recovered successfully without surgical intervention. S. pneumoniae serotype 6B can cause lung abscess.

  4. Causative species and serotypes of shigellosis in mainland China: systematic review and meta-analysis.

    Science.gov (United States)

    Chang, Zhili; Lu, Shuting; Chen, Lihong; Jin, Qi; Yang, Jian

    2012-01-01

    Shigella, the causative agent of shigellosis, is a major global public health concern, particularly in developing countries with poor sanitation. A comprehensive and current understanding of the prevalent species and serotypes of shigellosis is essential for both disease prevention and vaccine development. However, no current data are available on the causative species/serotypes of shigellosis in mainland China during the past decade. Relevant studies addressing the prevalent species of shigellosis in mainland China from January 2001 to December 2010 were identified from PubMed and the Chinese BioMedical Literature Database (in Chinese) until April 2012. A total of 131 eligible articles (136 studies) were included in this review. Meta-analyses showed that the prevalences of S. flexneri and S. sonnei were 76.2% (95% CI, 73.7%-78.5%) and 21.3% (95% CI, 19.0%-23.7%), respectively. Stratified analyses indicated a decrease in the prevalence of S. flexneri cases and an increase in the prevalence of S. sonnei cases concurrent with the rapid economic growth experienced by China in recent years. Moreover, significantly higher rates of S. sonnei were observed in the East, North and Northeast regions of China, as compared to the rest of the country. These phenomena imply the possible association between the prevalent species of Shigella and regional economic status; however, additional factors also exist and require further investigations. Moreover, the two major serotypes S. flexneri 2a and 4c accounted for 21.5% (95% CI, 16.7%-27.4%) and 12.9% (95% CI 9.8%-16.9%) of S. flexneri infections, respectively, in the past decade. However, these results were found to be frequently heterogeneous (p for Q tests review of the causative agents of shigellosis in mainland China and focuses on the importance of strengthening prevention and research efforts on S. sonnei and the newly emerged S. flexneri serotype 4c.

  5. Production of bacterial polysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Ellwood, D C; Evans, C G.T.; Yeo, R G

    1978-06-01

    A process for the biochemical synthesis of polysaccharides comprises growing polysaccharide-producing bacteria of the genus Xanthomonas in a single stage continuous culture in a chemically-defined medium. The term chemically-defined medium denotes a culture medium wherein nutrients other than carbon are provided as inorganic salts or single organic compounds of known molecular structure rather than as complex naturally-derived mixtures. Normally the only organic component of the chemically-defined medium will be a conventional carbon source such as a carbohydrate, especially glucose, or glycerol. Preferably the medium should contain only one nitrogen source, since the use of multiple nitrogen sources, as present in complex media, appears to promote changes in the nature of the culture resulting in loss of polysaccharide production. 22 claims.

  6. Preliminary 19F-MRS Study of Tumor Cell Proliferation with 3′-deoxy-3′-fluorothymidine and Its Metabolite (FLT-MP

    Directory of Open Access Journals (Sweden)

    In Ok Ko

    2017-01-01

    Full Text Available The thymidine analogue 3′-deoxy-3′-[18F]fluorothymidine, or [18F]fluorothymidine ([18F]FLT, is used to measure tumor cell proliferation with positron emission tomography (PET imaging technology in nuclear medicine. FLT is phosphorylated by thymidine kinase 1 (TK1 and then trapped inside cells; it is not incorporated into DNA. Imaging with 18F-radiolabeled FLT is a noninvasive technique to visualize cellular proliferation in tumors. However, it is difficult to distinguish between [18F]FLT and its metabolites by PET imaging, and quantification has not been attempted using current imaging methods. In this study, we successfully acquired in vivo F19 spectra of natural or nonradioactive 3′-deoxy-3′-fluorothymidine ([19F]FLT and its monophosphate metabolite (FLT-MP in a tumor xenograft mouse model using 9.4T magnetic resonance imaging (MRI. This preliminary result demonstrates that 19F magnetic resonance spectroscopy (MRS with FLT is suitable for the in vivo assessment of tumor aggressiveness and for early prediction of treatment response.

  7. Serotype distribution of Streptococcus pneumoniae causing invasive disease in the Republic of Ireland.

    LENUS (Irish Health Repository)

    Vickers, I

    2011-05-01

    The 7-valent pneumococcal conjugate vaccine (PCV7) was included in the routine infant immunization schedule in Ireland in September 2008. We determined the serotype of 977 S. pneumoniae isolates causing invasive disease between 2000-2002 and 2007-2008, assessed for the presence of the recently described serotype 6C and determined the susceptibility of isolates during 2007-2008 to penicillin and cefotaxime. Serotype 14 was the most common serotype during both periods and 7·7% of isolates previously typed as serotype 6A were serotype 6C. During 2000-2002 and 2007-2008, PCV7 could potentially have prevented 85% and 74% of invasive pneumococcal disease in the target population (i.e. children aged <2 years), respectively. The level of penicillin non-susceptibility was 17% in 2007-2008. Ongoing surveillance of serotypes is required to determine the impact of PCV7 in the Irish population and to assess the potential of new vaccines with expanded valency.

  8. Structural modification of polysaccharides: A biochemical-genetic approach

    Science.gov (United States)

    Kern, Roger G.; Petersen, Gene R.

    1991-01-01

    Polysaccharides have a wide range of industrial and biomedical applications. An industry trend is underway towards the increased use of bacteria to produce polysaccharides. Long term goals of this work are the adaptation and enhancement of saccharide properties for electronic and optic applications. In this report we illustrate the application of enzyme-bearing bacteriophage on strains of the enteric bacterium Klebsiella pneumoniae, which produces a polysaccharide with the relatively rare rheological property of drag-reduction. This has resulted in the production of new polysaccharides with enhanced rheological properties. Our laboratory is developing techniques for processing and structurally modifying bacterial polysaccharides and oligosaccharides which comprise their basic polymeric repeat units. Our research has focused on bacteriophage which produce specific polysaccharide degrading enzymes. This has lead to the development of enzymes generated by bacteriophage as tools for polysaccharide modification and purification. These enzymes were used to efficiently convert the native material to uniform-sized high molecular weight polymers, or alternatively into high-purity oligosaccharides. Enzyme-bearing bacteriophage also serve as genetic selection tools for bacteria that produce new families of polysaccharides with modified structures.

  9. Streptococcus pneumoniae serotype-2 childhood meningitis in Bangladesh: a newly recognized pneumococcal infection threat.

    Directory of Open Access Journals (Sweden)

    Samir K Saha

    Full Text Available BACKGROUND: Streptococcus pneumoniae is a leading cause of meningitis in countries where pneumococcal conjugate vaccines (PCV targeting commonly occurring serotypes are not routinely used. However, effectiveness of PCV would be jeopardized by emergence of invasive pneumococcal diseases (IPD caused by serotypes which are not included in PCV. Systematic hospital based surveillance in Bangladesh was established and progressively improved to determine the pathogens causing childhood sepsis and meningitis. This also provided the foundation for determining the spectrum of serotypes causing IPD. This article reports an unprecedented upsurge of serotype 2, an uncommon pneumococcal serotype, without any known intervention. METHODS AND FINDINGS: Cases with suspected IPD had blood or cerebrospinal fluid (CSF collected from the beginning of 2001 till 2009. Pneumococcal serotypes were determined by capsular swelling of isolates or PCR of culture-negative CSF specimens. Multicenter national surveillance, expanded from 2004, identified 45,437 patients with suspected bacteremia who were blood cultured and 10,618 suspected meningitis cases who had a lumber puncture. Pneumococcus accounted for 230 culture positive cases of meningitis in children <5 years. Serotype-2 was the leading cause of pneumococcal meningitis, accounting for 20.4% (45/221; 95% CI 15%-26% of cases. Ninety eight percent (45/46 of these serotype-2 strains were isolated from meningitis cases, yielding the highest serotype-specific odds ratio for meningitis (29.6; 95% CI 3.4-256.3. The serotype-2 strains had three closely related pulsed field gel electrophoresis types. CONCLUSIONS: S. pneumoniae serotype-2 was found to possess an unusually high potential for causing meningitis and was the leading serotype-specific cause of childhood meningitis in Bangladesh over the past decade. Persisting disease occurrence or progressive spread would represent a major potential infection threat since serotype-2

  10. Direct Comparison of Immunogenicity Induced by 10- or 13-Valent Pneumococcal Conjugate Vaccine around the 11-Month Booster in Dutch Infants.

    Directory of Open Access Journals (Sweden)

    Alienke J Wijmenga-Monsuur

    Full Text Available Since 2009/10, a 10- and a 13-valent pneumococcal conjugate vaccine (PCV are available, but only the 10-valent vaccine is now being used for the children in the Netherlands. As the vaccines differ in number of serotypes, antigen concentration, and carrier proteins this study was designed to directly compare quantity and quality of the antibody responses induced by PCV10 and PCV13 before and after the 11-month booster.Dutch infants (n = 132 were immunized with either PCV10 or PCV13 and DTaP-IPV-Hib-HepB at the age of 2, 3, 4 and 11 months. Blood samples were collected pre-booster and post-booster at one week and one month post-booster for quantitative and qualitative immunogenicity against 13 pneumococcal serotypes, as well as quantitative immunogenicity against diphtheria, tetanus, pertussis and Haemophilus influenzae type b. We compared immunogenicity induced by PCV13 and PCV10 for their ten shared serotypes.One month post-booster, pneumococcal serotype-specific IgG geometric mean concentrations (GMCs for the PCV13 group were higher compared with the PCV10 group for six serotypes, although avidity was lower. Serotype 19F showed the most distinct difference in IgG and, in contrast to other serotypes, its avidity was higher in the PCV13 group. One week post-booster, opsonophagocytosis for serotype 19F did not differ significantly between the PCV10- and the PCV13 group.Both PCV10 and PCV13 were immunogenic and induced a booster response. Compared to the PCV10 group, the PCV13 group showed higher levels for serotype 19F GMCs and avidity, pre- as well as post-booster, although opsonophagocytosis did not differ significantly between groups. In our study, avidity is not correlated to opsonophagocytotic activity (OPA and correlations between IgG and OPA differ per serotype. Therefore, besides assays to determine IgG GMCs, assays to detect opsonophagocytotic activity, i.e., the actual killing of the pneumococcus, are important for PCV evaluation. How

  11. Liposome-Based Delivery Systems in Plant Polysaccharides

    International Nuclear Information System (INIS)

    Meiwan, C.; Yitao, W.; Yanfang, Z.; Xinsheng, P.; Jingjing, H.; Ping, Z.

    2012-01-01

    Plant polysaccharides consist of many monosaccharide by α or β glycosidic bond which can be extracted by the water, alcohol, lipophile liquid from a variety of plants including Cordyceps sinensis, astragalus, and mushrooms. Recently, many evidences illustrate that natural plant polysaccharides possess various biological activities including strengthening immunity, lowering blood sugar, regulating lipid metabolism, anti oxidation, anti aging, and antitumour. Plant polysaccharides have been widely used in the medical field due to their special features and low toxicity. As an important drug delivery system, liposomes can not only encapsulate small-molecule compound but also big-molecule drug; therefore, they present great promise for the application of plant polysaccharides with unique physical and chemical properties and make remarkable successes. This paper summarized the current progress in plant polysaccharides liposomes, gave an overview on their experiment design method, preparation, and formulation, characterization and quality control, as well as in vivo and in vitro studies. Moreover, the potential application of plant polysaccharides liposomes was prospected as well.

  12. The prevalence of dengue virus serotypes in asymptomatic blood donors reveals the emergence of serotype 4 in Saudi Arabia.

    Science.gov (United States)

    Ashshi, Ahmed Mohamed

    2017-06-09

    Transmission of dengue virus (DENV) through blood transfusion has been documented and hence screening for DENV during blood donation has been recently recommended by the American Association of Blood Banks and Centres of Disease Control and Prevention. DENV is endemic in the Western province of the Kingdom of Saudi Arabia (KSA) and serotypes 1, 2 and 3, but not 4, have been detected. However, little is known regarding the rates of DENV during blood donation in the kingdom. The aim of this study was therefore to measure the prevalence of dengue virus and its serotypes in eligible Saudi blood donors in the endemic Western region of KSA. This was a cross-sectional study and serum samples were collected from 910 eligible Saudi male blood donors. DENV IgM and IgG antibodies were measured serologically by ELISA while viral serotypes were detected by a single step IVD CE certified multiplex RT-PCR kit. The overall prevalence was 39 and 5.5% for IgG+ and IgM+, respectively. There were 12 (1.3%) with exclusively IgM+, 317 (34.8%) exclusively IgG+ and 38 (4.2%) with dual IgM+/IgG+ donors. The overall prevalence was 3.2% (n = 29) and 2.3% (n = 21) for primary and secondary infections. PCR was positive in 5.5% (n = 50) and, DENV-2 (n = 24; 48%) was the most frequent serotype and was significantly higher than DENV-1 (20%; P = 0.02) and DENV-3 (2%; P = 0.1 × 10 -5 ) but not DENV-4 (30%; P = 0.2). There was no significant difference between both DENV-4 and DENV-1 (P = 0.4). The combination of the PCR and serology findings showed that 22 (2.4%) and 28 (3.1%) donors had primary and secondary viremic infections, respectively. The detected rates of DENV by PCR suggest a potential high risk of viral transmission by blood transfusion. To the best of our knowledge, this study is the first to report the detection of DENV-4 serotype in Saudi Arabia. More studies are required to measure the precise prevalence of DENV serotypes and their potential

  13. Fast and simultaneous determination of 1 H-1 H and 1 H-19 F scalar couplings in complex spin systems: Application of PSYCHE homonuclear broadband decoupling.

    Science.gov (United States)

    Kakita, Veera Mohana Rao; Rachineni, Kavitha; Hosur, Ramakrishna V

    2017-07-21

    The present manuscript focuses on fast and simultaneous determination of 1 H- 1 H and 1 H- 19 F scalar couplings in fluorinated complex steroid molecules. Incorporation of broadband PSYCHE homonuclear decoupling in the indirect dimension of zero-quantum filtered diagonal experiments (F1-PSYCHE-DIAG) suppresses 1 H- 1 H scalar couplings; however, it retains 1 H- 19 F scalar couplings (along F1 dimension) for the 19 F coupled protons while preserving the pure-shift nature for 1 H resonances uncoupled to 19 F. In such cases, along the direct dimensions, 1 H- 1 H scalar coupling multiplets deconvolute and they appear as duplicated multiplets for the 19 F coupled protons, which facilitates unambiguous discrimination of 19 F coupled 1 H chemical sites from the others. Further, as an added advantage, data acquisition has been accelerated by invoking the known ideas of spectral aliasing in the F1-PSYCHE-DIAG scheme and experiments demand only ~10 min of spectrometer times. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Sources of carrier F-19 in F-18 fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Link, J. M.; Shoner, S. C.; Krohn, K. A. [University of Washington, Department of Radiology, Molecular Imaging Center, 1959 NE Pacific St., Box 356004, Seattle, WA 98195-6004 (United States)

    2012-12-19

    Fluorine-18 is used for many PET radiopharmaceuticals. Theoretically {sup 18}F should be carrier free and a good candidate for nanochemistry. However, {sup 18}F has 10 to 1000 times more stable fluorine atoms than radioactive atoms. In order to understand the source of carrier fluoride and other ions associated with {sup 18}F radiosynthesis, anion concentrations of different components of {sup 18}F target systems as well as solvents and chemicals used in radiosynthesis were measured. Results: The enriched water used for production of {sup 18}F had low levels of anions. In general, the sources of anions, particularly of fluoride, were the chemical reagents used for synthesis and trace contaminants in tubing, valves and fittings. A major component of contamination was nitrate from irradiation of dissolved nitrogen gas in the target water.

  15. Aislamiento de distintos serotipos de Haemophilus influenzae en muestras profundas de pacientes pediátricos Isolation of Haemophilus influenzae serotypes from sterile sites in sick children

    Directory of Open Access Journals (Sweden)

    B.M. Gatti

    2004-03-01

    Full Text Available Haemophilus influenzae (Hi es responsable de diversas enfermedades humanas como sepsis, meningitis, celulitis y osteoartritis. En este trabajo se investigó la recuperación de distintos serotipos de Hi en muestras profundas de pacientes pediátricos. Se estudiaron 179 aislamientos de 146 niños durante el periodo 1996-2002 en el Laboratorio de Microbiología del Hospital de Niños Superiora Sor María Ludovica, Argentina. La distribución de los serotipos fue la siguiente: 1 a, 112 b, 1 c,1 d, 4 e, 3 f y 24 no tipificables. A partir del establecimiento de la estrategia de vacunación universal anti Hi b en 1998 se observa una disminución notable del serotipo b y un aumento relativo de otros y no tipificables.Haemophilus influenzae (Hi is the causative agent of several human diseases such as sepsis, meningitis, celulitis, and osteoarthritis. We investigated the isolation of Hi serotypes from sterile sites in sick children. One hundred and seventy nine strains from 146 patients were studied, period 1996-2002, at the Microbiology Laboratory, Hospital de Niños Superiora Sor María Ludovica, Argentina. The serotype distribution was:1 a, 112 b,1 c,1 d, 4 e, 3 f y 24 no typable. Since the beginning of universal Hi b vaccination in 1998, we have observed the fast decrease of serotype b and a relative increase of other serotypes.

  16. Antigen processing of glycoconjugate vaccines; the polysaccharide portion of the pneumococcal CRM(197) conjugate vaccine co-localizes with MHC II on the antigen processing cell surface.

    Science.gov (United States)

    Lai, Zengzu; Schreiber, John R

    2009-05-21

    Pneumococcal (Pn) polysaccharides (PS) are T-independent (TI) antigens and do not induce immunological memory or antibodies in infants. Conjugation of PnPS to the carrier protein CRM(197) induces PS-specific antibody in infants, and memory similar to T-dependent (Td) antigens. Conjugates have improved immunogenicity via antigen processing and presentation of carrier protein with MHC II and recruitment of T cell help, but the fate of the PS attached to the carrier is unknown. To determine the location of the PS component of PnPS-CRM(197) in the APC, we separately labeled PS and protein and tracked their location. The PS of types 14-CRM(197) and 19F-CRM(197) was specifically labeled by Alexa Fluor 594 hydrazide (red). The CRM(197) was separately labeled red in a reaction that did not label PS. Labeled antigens were incubated with APC which were fixed, permeabilized and incubated with anti-MHC II antibody labeled green by Alexa Fluor 488, followed by confocal microscopy. Labeled CRM(197) was presented on APC surface and co-localized with MHC II (yellow). Labeled unconjugated 14 or 19F PS did not go to the APC surface, but PS labeled 14-CRM(197) and 19F-CRM(197) was internalized and co-localized with MHC II. Monoclonal antibody to type 14 PS bound to intracellular type 14 PS and PS-CRM(197). Brefeldin A and chloroquine blocked both CRM(197) and PS labeled 14-CRM(197) and 19F-CRM(197) from co-localizing with MHC II. These data suggest that the PS component of the CRM(197) glycoconjugate enters the endosome, travels with CRM(197) peptides to the APC surface and co-localizes with MHC II.

  17. Isolation of a bacteriophage specific for a new capsular type of Klebsiella pneumoniae and characterization of its polysaccharide depolymerase.

    Directory of Open Access Journals (Sweden)

    Chun-Ru Hsu

    Full Text Available BACKGROUND: Klebsiella pneumoniae is one of the major pathogens causing hospital-acquired multidrug-resistant infections. The capsular polysaccharide (CPS is an important virulence factor of K. pneumoniae. With 78 capsular types discovered thus far, an association between capsular type and the pathogenicity of K. pneumoniae has been observed. METHODOLOGY/PRINCIPAL FINDINGS: To investigate an initially non-typeable K. pneumoniae UTI isolate NTUH-K1790N, the cps gene region was sequenced. By NTUH-K1790N cps-PCR genotyping, serotyping and determination using a newly isolated capsular type-specific bacteriophage, we found that NTUH-K1790N and three other isolates Ca0507, Ca0421 and C1975 possessed a new capsular type, which we named KN2. Analysis of a KN2 CPS(- mutant confirmed the role of capsule as the target recognized by the antiserum and the phage. A newly described lytic phage specific for KN2 K. pneumoniae, named 0507-KN2-1, was isolated and characterized using transmission electron microscopy. Whole-genome sequencing of 0507-KN2-1 revealed a 159 991 bp double-stranded DNA genome with a G+C content of 46.7% and at least 154 open reading frames. Based on its morphological and genomic characteristics, 0507-KN2-1 was classified as a member of the Myoviridae phage family. Further analysis of this phage revealed a 3738-bp gene encoding a putative polysaccharide depolymerase. A recombinant form of this protein was produced and assayed to confirm its enzymatic activity and specificity to KN2 capsular polysaccharides. KN2 K. pneumoniae strains exhibited greater sensitivity to this depolymerase than these did to the cognate phage, as determined by spot analysis. CONCLUSIONS/SIGNIFICANCE: Here we report that a group of clinical strains possess a novel Klebsiella capsular type. We identified a KN2-specific phage and its polysaccharide depolymerase, which could be used for efficient capsular typing. The lytic phage and depolymerase also have potential as

  18. A Monoclonal Antibody Based Capture ELISA for Botulinum Neurotoxin Serotype B: Toxin Detection in Food

    Directory of Open Access Journals (Sweden)

    Larry H. Stanker

    2013-11-01

    Full Text Available Botulism is a serious foodborne neuroparalytic disease, caused by botulinum neurotoxin (BoNT, produced by the anaerobic bacterium Clostridium botulinum. Seven toxin serotypes (A–H have been described. The majority of human cases of botulism are caused by serotypes A and B followed by E and F. We report here a group of serotype B specific monoclonal antibodies (mAbs capable of binding toxin under physiological conditions. Thus, they serve as capture antibodies for a sandwich (capture ELISA. The antibodies were generated using recombinant peptide fragments corresponding to the receptor-binding domain of the toxin heavy chain as immunogen. Their binding properties suggest that they bind a complex epitope with dissociation constants (KD’s for individual antibodies ranging from 10 to 48 × 10−11 M. Assay performance for all possible combinations of capture-detector antibody pairs was evaluated and the antibody pair resulting in the lowest level of detection (L.O.D., ~20 pg/mL was determined. Toxin was detected in spiked dairy samples with good recoveries at concentrations as low as 0.5 pg/mL and in ground beef samples at levels as low as 2 ng/g. Thus, the sandwich ELISA described here uses mAb for both the capture and detector antibodies (binding different epitopes on the toxin molecule and readily detects toxin in those food samples tested.

  19. A monoclonal antibody based capture ELISA for botulinum neurotoxin serotype B: toxin detection in food.

    Science.gov (United States)

    Stanker, Larry H; Scotcher, Miles C; Cheng, Luisa; Ching, Kathryn; McGarvey, Jeffery; Hodge, David; Hnasko, Robert

    2013-11-18

    Botulism is a serious foodborne neuroparalytic disease, caused by botulinum neurotoxin (BoNT), produced by the anaerobic bacterium Clostridium botulinum. Seven toxin serotypes (A-H) have been described. The majority of human cases of botulism are caused by serotypes A and B followed by E and F. We report here a group of serotype B specific monoclonal antibodies (mAbs) capable of binding toxin under physiological conditions. Thus, they serve as capture antibodies for a sandwich (capture) ELISA. The antibodies were generated using recombinant peptide fragments corresponding to the receptor-binding domain of the toxin heavy chain as immunogen. Their binding properties suggest that they bind a complex epitope with dissociation constants (KD's) for individual antibodies ranging from 10 to 48 × 10-11 M. Assay performance for all possible combinations of capture-detector antibody pairs was evaluated and the antibody pair resulting in the lowest level of detection (L.O.D.), ~20 pg/mL was determined. Toxin was detected in spiked dairy samples with good recoveries at concentrations as low as 0.5 pg/mL and in ground beef samples at levels as low as 2 ng/g. Thus, the sandwich ELISA described here uses mAb for both the capture and detector antibodies (binding different epitopes on the toxin molecule) and readily detects toxin in those food samples tested.

  20. Chromosome sizes and phylogenetic relationships between serotypes of Actinobacillus pleuropneumoniae

    OpenAIRE

    Chevallier, Bruno; Dugourd, Dominique; Tarasiuk, Kazimirez; Harel, Josée; Gottschalk, Marcelo; Kobisch, Marylène; Frey, Joachim

    2017-01-01

    The genome size of Actinobacillus pleuropneumoniae was determined by pulsed field gel electrophoresis of AscI and ApaI digested chromosomal DNA. The genome size of the type strain 4074T (serotype 1) was determined to be 2404±40 kb. The chromosome sizes for the reference strains of the other serotypes range between 2.3 and 2.4 Mb. The restriction pattern profiles of AscI, ApaI and NheI digested chromosomes showed a high degree of polymorphism among the different serotype reference strains and ...

  1. Antimicrobial susceptibility and serotypes of Actinobacillus (Haemophilus) pleuropneumoniae recovered from Missouri swine.

    Science.gov (United States)

    Fales, W H; Morehouse, L G; Mittal, K R; Bean-Knudsen, C; Nelson, S L; Kintner, L D; Turk, J R; Turk, M A; Brown, T P; Shaw, D P

    1989-01-01

    The antimicrobial susceptibility of 73 Actinobacillus (Haemophilus) pleuropneumoniae isolates from swine in Missouri was determined with a microdilution minimal inhibitory concentration test system. Serotyping was accomplished by means of co-agglutination. Serotype 1 (39/73) and serotype 5 (30/73) were commonly found, whereas serotype 7 (4/73) was infrequently encountered. Most isolates (MIC90) were found susceptible to ampicillin (amoxicillin), cephalothin, penicillin, erythromycin, gentamicin, and kanamycin. Marked resistance was found with oxytetracycline, tylosin, and sulfadimethoxine. The data indicate that use of ampicillin (amoxicillin) or penicillin may correlate well with the favorable outcome of treatment.

  2. Cytochemical Localization of Polysaccharides in Dendrobium officinale and the Involvement of DoCSLA6 in the Synthesis of Mannan Polysaccharides

    OpenAIRE

    He, Chunmei; Wu, Kunlin; Zhang, Jianxia; Liu, Xuncheng; Zeng, Songjun; Yu, Zhenming; Zhang, Xinghua; Teixeira da Silva, Jaime A.; Deng, Rufang; Tan, Jianwen; Luo, Jianping; Duan, Jun

    2017-01-01

    Dendrobium officinale is a precious traditional Chinese medicinal plant because of its abundant polysaccharides found in stems. We determined the composition of water-soluble polysaccharides and starch content in D. officinale stems. The extracted water-soluble polysaccharide content was as high as 35% (w/w). Analysis of the composition of monosaccharides showed that the water-soluble polysaccharides were dominated by mannose, to a lesser extent glucose, and a small amount of galactose, in a ...

  3. Different metabolic profiles of K1 serotype and non-serotype K1 and K2 Klebsiella pneumoniae isolates in oral infection mice model.

    Science.gov (United States)

    Chen, Nan; Wang, Lin-Lin; Xue, Juan; Ma, Xiang-Bo; Zhao, Sheng; Rong, Rui-Xue; Li, Hong-Quan; Ding, Liang; Zheng, Ming-Zhi; Chen, Ying-Ying; Duan, Fei; Shen, Yue-Liang

    2014-10-01

    K1 or K2 serotype Klebsiella pneumoniae isolate caused clinical pyogenic liver abscess (KLA) infection is prevalent in many areas. It has been identified that K1 or K2 serotype K. pneumoniae isolates caused KLA infection in mice by oral inoculation. In our study, K1 serotype K. pneumoniae isolate Kp1002 with hypermucoviscosity (HV)-positive phenotype caused KLA infection in C57BL/6 mice by oral inoculation. Simultaneously, non-serotype K1 and K2 isolate Kp1014 with HV-negative phenotype failed to cause KLA infection in the same manner. It seems that gastrointestinal tract translocation is the pathway by which K1 or K2 serotype K. pneumoniae caused KLA infection. Liquid chromatography-tandem mass spectrometry was used to further analyze metabolic profile changes in mice with KLA infection. Data showed that after Kp1002 or Kp1014 oral inoculation, serum Phosphatidylcholine (PC) and Lysophosphatidylcholine (LPC) levels significantly changed in mice. Some PC and LPC molecules showed changes both in the Kp1002 KLA group and the Kp1014 no-KLA group compared with the control group. The level of 18:1/18:2-PC significantly changed in the Kp1002 KLA group compared with the control group, but showed no change between the Kp1014 no-KLA group and the control group. The level of 18:1/18:2-PC might have been particularly affected by KLA infection caused by K1 serotype K. pneumoniae Kp1002. It may be a potential biomarker for KLA infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Research of polysaccharide complexes from asteraceae family plants

    Directory of Open Access Journals (Sweden)

    Світлана Михайлівна Марчишин

    2015-10-01

    Full Text Available Aim of research. Depth study of polysaccharides in some little-known plant species of Asteraceae family is pressing question, considering that polysaccharides are important biologically active compounds widely used in pharmaceutical and medical practice as remedies and preventive medications. The aim of research was to determinate both quantitative content and monomeric composition of polysaccharide complexes from Asteraceae family plant species – Tagetes genus, Arnica genus, and Bellis genus.Materials and methods. Determination of polysaccharides was carried out by the precipitation reaction, using 96 % ethyl alcohol P and Fehling's solution after acid hydrolysis; quantitative content of this group of compounds was determined by gravimetric analysis. On purpose to identify the monomeric composition hydrolysis under sulfuric acid conditions was conducted. Qualitative monomeric composition of polysaccharides after hydrolysis was carried out by paper chromatography method in n-Butanol – Pyridine – Distilled water P (6:4:3 system along with saccharides reference samples.Results. Polysaccharide complexes from Tagetes erecta, Tagetes patula, Tagetes tenuifolia, Arnica montana, Arnica foliosa, wild and cultivated Bellis perennis herbs were studied. Water-soluble polysaccharides and pectin fractions were isolated from studied objects; their quantitative content and monomeric composition were determined.Conclusion. The highest amount of water-soluble polysaccharides was found in cultivated Bellis perennis herb (10,13 %, the highest amount of pectin compounds – in Tagetes tenuifolia herb (13,62 %; the lowest amount of water-soluble polysaccharides and pectin compounds was found in Arnica montana herb (4,61 % and Tagetes patula herb (3,62 %, respectively. It was found that polysaccharide complexes from all studied species include glucose and arabinose

  5. Determination of tea fluorine concentration with 19F(p, αγ)16O prompt nuclear reaction analysis

    International Nuclear Information System (INIS)

    Liang Daihua; Shen Guantao; Li Deyi; Wu Junheng

    1987-01-01

    Experiments of 19 F(p, αγ) 16 O prompt nuclear reaction analyses of tea F contents were performed on a Cockroft-Walton accelerator. The principle and apparatus are described. More than 150 varieties tea samples were examined. Results show that for the same variety of tea samples, the higher the grade of the tea, the higher the F concentration it contains, and for different varieties, the better the tea, the lower the F concentration of the tea

  6. Regional tumor oximetry: 19F NMR spectroscopy of hexafluorobenzene

    International Nuclear Information System (INIS)

    Hunjan, Sandeep; Mason, Ralph P.; Constantinescu, Anca; Peschke, Peter; Hahn, Eric W.; Antich, Peter P.

    1998-01-01

    Purpose: An accurate method for monitoring oxygen tension (pO 2 ) of individual tumors could be valuable for optimizing treatment plans. We have recently shown that 19 F nuclear magnetic resonance (NMR) spin-lattice relaxometry of hexafluorobenzene (HFB) provides a highly sensitive indicator of tumor oxygenation. We have now refined the methodology to provide enhanced precision, and applied the method to investigate dynamic changes in tumor oxygenation. Methods and Materials: Dunning prostate adenocarcinoma R3327-AT1 was grown in the form of pedicles on the foreback of male Copenhagen rats. When the tumors reached ≅1 cm diameter, HFB (20 μl) was administered, either centrally or peripherally, by direct intratumoral (IT) injection. Local pO 2 was determined using pulse-burst saturation recovery (PBSR) 19 F NMR spectroscopy on the basis of the spin-lattice relaxation rate, R1. Results: Interrogation of the central region of tumors provided typical values in the range pO 2 = 1.4-6.4 mmHg, with a typical stability of ±2 mmHg over a period of 20 min, when rats breathed 33% O 2 . Altering the inhaled gas to oxygen or carbogen (95% O 2 /5% CO 2 ) produced no significant change. In contrast, interrogation of tumor periphery indicated baseline pO 2 in the range 7.9-78.9 mmHg. Altering inspired gas produced significant changes (p 2 or carbogen, although the change was generally greater with carbogen. In each case, pO 2 returned to baseline within 16 min of returning the inhaled gas to baseline. Conclusion: We believe this method provides a valuable new approach with the requisite precision and accuracy to investigate tumor pO 2

  7. Statistical Analysis Of Tank 19F Floor Sample Results

    International Nuclear Information System (INIS)

    Harris, S.

    2010-01-01

    Representative sampling has been completed for characterization of the residual material on the floor of Tank 19F as per the statistical sampling plan developed by Harris and Shine. Samples from eight locations have been obtained from the tank floor and two of the samples were archived as a contingency. Six samples, referred to in this report as the current scrape samples, have been submitted to and analyzed by SRNL. This report contains the statistical analysis of the floor sample analytical results to determine if further data are needed to reduce uncertainty. Included are comparisons with the prior Mantis samples results to determine if they can be pooled with the current scrape samples to estimate the upper 95% confidence limits (UCL95%) for concentration. Statistical analysis revealed that the Mantis and current scrape sample results are not compatible. Therefore, the Mantis sample results were not used to support the quantification of analytes in the residual material. Significant spatial variability among the current scrape sample results was not found. Constituent concentrations were similar between the North and South hemispheres as well as between the inner and outer regions of the tank floor. The current scrape sample results from all six samples fall within their 3-sigma limits. In view of the results from numerous statistical tests, the data were pooled from all six current scrape samples. As such, an adequate sample size was provided for quantification of the residual material on the floor of Tank 19F. The uncertainty is quantified in this report by an UCL95% on each analyte concentration. The uncertainty in analyte concentration was calculated as a function of the number of samples, the average, and the standard deviation of the analytical results. The UCL95% was based entirely on the six current scrape sample results (each averaged across three analytical determinations).

  8. Familias de la proteína de superficie PspA de Streptococcus pneumoniae: Relación con serotipos y localización Pneumococcal surface protein A (PspA families: Relation with serotypes and clinical site of infection

    Directory of Open Access Journals (Sweden)

    Clara Mayoral

    2010-10-01

    Full Text Available PspA, proteína de superficie de Streptococcus pneumoniae es un factor de virulencia, fuertemente inmunogénica y común a todos los serotipos. Aunque el gen que codifica para esta proteína presenta una marcada heterogeneidad en la región correspondiente al N-terminal, la PspA contiene epitopes conservados de manera tal que la inmunización genera protección contra neumococos pertenecientes a diversos tipos capsulares y con distintas PspA. A pesar del marcado polimorfismo del gen pspA es posible agrupar las distintas variantes en 3 familias mayoritarias. Estas propiedades las convierten en candidatas ideales para elaborar vacunas. Debido a que la mayoría de los trabajos sobre identificación de familias fueron realizados sobre serotipos frecuentes en otros países, el objetivo fue identificar las familias de PspA de aislamientos de pacientes de nuestra región y relacionarlas con los serotipos prevalentes y patologías. Se estudiaron 70 aislamientos, provenientes de niños con infecciones invasoras. Se aplicó una PCR utilizando cebadores específicos de cada familia. El 60% fueron familia 1 y 34% familia 2. En un 6% no se identificó ninguna de las familias de PspA. Los serotipos 1 y 5 presentaron familia 1 únicamente; los serotipos 14, 6B, 19F y 18C mostraron genes de ambas familias. La familia 1 se observó en 60% de las neumonías y 50% de las meningitis. La familia 2 en 33% de neumonías y 50% de meningitis. Esta información podría ser un valioso aporte para la formulación de una vacuna regional efectiva utilizando PspA recombinante como inmunógeno.PspA, a pneumococcal surface protein, is highly immunogenic and common to all serotypes. Although pspA gene shows a great heterogeneity at the N-terminal region, PspA protein has conserved epytopes which are able to elicit protective cross-reaction against various serotypes presenting different PspA. In spite of the high polimorfism of the PspA, three majority families can be identified

  9. [Ability of procalcitonin to predict bacteremia in patients with community acquired pneumonia].

    Science.gov (United States)

    Julián-Jiménez, Agustín; Timón Zapata, Jesús; Laserna Mendieta, Emilio José; Parejo Miguez, Raquel; Flores Chacartegui, Manuel; Gallardo Schall, Pablo

    2014-04-07

    To analyze the usefulness and ability of procalcitonin (PCT) to predict the presence of bacteremia in patients with community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae (S. pneumoniae) or other bacteria. This is an observational, prospective and descriptive study involving patients who were diagnosed with CAP in our Emergency Department. Data collected included socio-demographic and comorbidity variables, Charlson index, stage in the Pneumonia Severity Index and criteria of severe NAC, microbiologic studies and biomarker determinations (PCT and C reactive protein). The follow-up was carried out during 30 days to calculate the predictive power and the diagnostic performance for bacteremia caused or not by S. pneumoniae. Four hundred and seventy-four patients were finally included in the study. Blood cultures were positive in 85 individuals (17.9%) and S. pneumoniae was identified as the responsible pathogen in 75 of them (88.4%) (in 5 cases together with another agent). The area under the Receiver Operating Characteristic curve for PCT to predict bacteremia (caused by S. pneumoniae or not) was 0.988 (95% confidence interval 0.908-0.995; P98% and>10, respectively. The most frequently isolated serotypes of S. pneumoniae were 19A, 7F, 1 and 3. The highest mean levels of PCT were found in serotypes 7F, 19A, 3 and 1, which showed statistically significant differences with regard to the others serotypes considered (P=.008). Serotypes associated with the highest percentage of severe sepsis-septic shock, 30-days mortality and multi-lobe or bilateral affection were 3, 1 and 19A; 1, 3 and 19A; and 3, 19A and 6A, respectively. PCT had a remarkable diagnostic ability to discard or suspect bacteremia and to guide the etiology of CAP caused by S. pneumoniae. Serotypes 1, 3, 19A and 7F showed greater frequency, systemic inflammatory response and clinical severity. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  10. Structure resolution of Ba5Al3F19 and Iivestigation of fluorine ion dynamics by synchrotron powder diffraction, variable-temperature solid-state NMR, and quantum computations

    International Nuclear Information System (INIS)

    Martineau, C.; Fayon, F.; Suchomel, M.R.; Allix, M.; Massiot, D.; Taulelle, F.

    2011-01-01

    The room temperature structure of Ba 5 Al 3 F 19 has been solved using electron microscopy and synchrotron powder diffraction data. One-dimensional (1D) 27 Al and ultrafast magic-angle-spinning (MAS) 19 F NMR spectra have been recorded and are in agreement with the proposed structural model for Ba 5 Al 3 F 19 . The 19 F isotropic chemical shift and 27 Al quadrupolar parameters have been calculated using the CASTEP code from the experimental and density functional theory geometry-optimized structures. After optimization, the calculated NMR parameters of both the 19 F and 27 Al nuclei show improved consistency with the experimental values, demonstrating that the geometry optimization step is necessary to obtain more accurate and reliable structural data. This also enables a complete and unambiguous assignment of the 19 F MAS NMR spectrum of Ba 5 Al 3 F 19 . Variable-temperature 1D MAS 19 F NMR experiments have been carried out, showing the occurrence of fluorine ion mobility. Complementary insights were obtained from both two-dimensional (2D) exchange and 2D double-quantum dipolar recoupling NMR experiments, and a detailed analysis of the anionic motion in Ba 5 Al 3 F 19 is proposed, including the distinction between reorientational processes and chemical exchange involving bond breaking and re-formation.

  11. Imported dengue from 2013 Angola outbreak: Not just serotype 1 was detected.

    Science.gov (United States)

    Abreu, Cândida; Silva-Pinto, André; Lazzara, Daniela; Sobrinho-Simões, Joana; Guimarães, João Tiago; Sarmento, António

    2016-06-01

    All the reports from Angola's 2013 dengue outbreak revealed serotype 1. However, previously dengue serotypes 1-4 have been reported in Africa and in 2014 serotype 4 was reported in Angola. To report dengue serotypes in patients returning from Angola during 2013 outbreak. Retrospective, cross-sectional study. We serotyped the dengue by an in house Polymerase Chain Reaction technique in randomly selected cases. From the 2013 Angola's dengue outbreak we treated 47 adult patients. None had history of past dengue. A combo kit test for dengue revealed positive NS1 antigen in 39 and IgM antibodies in 8. From 17 randomly patients tested by RNA Real Time-PCR, 11 were positive: 7 for DENV-1, 2 for DENV-2, 1 for DENV-3 (co-infected with DENV-1) and 1 for DENV-4. None had a complicated or fatal evolution. Unlike previous reports the 4 serotypes were detected, and this resulted in a different epidemiological situation, raising the risk of future outbreaks of severe dengue. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Functions of some capsular polysaccharide biosynthetic genes in Klebsiella pneumoniae NTUH K-2044.

    Directory of Open Access Journals (Sweden)

    Jin-Yuan Ho

    Full Text Available The growing number of Klebsiella pneumoniae infections, commonly acquired in hospitals, has drawn great concern. It has been shown that the K1 and K2 capsular serotypes are the most detrimental strains, particularly to those with diabetes. The K1 cps (capsular polysaccharide locus in the NTUH-2044 strain of the pyogenic liver abscess (PLA K. pneumoniae has been identified recently, but little is known about the functions of the genes therein. Here we report characterization of a group of cps genes and their roles in the pathogenesis of K1 K. pneumoniae. By sequential gene deletion, the cps gene cluster was first re-delimited between genes galF and ugd, which serve as up- and down-stream ends, respectively. Eight gene products were characterized in vitro and in vivo to be involved in the syntheses of UDP-glucose, UDP-glucuronic acid and GDP-fucose building units. Twelve genes were identified as virulence factors based on the observation that their deletion mutants became avirulent or lost K1 antigenicity. Furthermore, deletion of kp3706, kp3709 or kp3712 (ΔwcaI, ΔwcaG or Δatf, respectively, which are all involved in fucose biosynthesis, led to a broad range of transcriptional suppression for 52 upstream genes. The genes suppressed include those coding for unknown regulatory membrane proteins and six multidrug efflux system proteins, as well as proteins required for the K1 CPS biosynthesis. In support of the suppression of multidrug efflux genes, we showed that these three mutants became more sensitive to antibiotics. Taken together, the results suggest that kp3706, kp3709 or kp3712 genes are strongly related to the pathogenesis of K. pneumoniae K1.

  13. Extraction, characterisation and antioxidant activity of Allium sativum polysaccharide.

    Science.gov (United States)

    Cheng, Hao; Huang, Gangliang

    2018-07-15

    Extraction and antioxidant activity of polysaccharide from Allium sativum were investigated. The crude polysaccharide was obtained by the hot-water extraction method. The molecular weight of polysaccharide deproteinized with CaCl 2 was 7.35×10 3 . It indicated that polysaccharide from Allium sativum consisted of three monosaccharides, namely fructose, glucose, and galactose by HPLC. The polysaccharide had the β-glycosidic bond. Moreover, it was proved that the polysaccharide had the potential scavenging ability to superoxide anions and hydroxyl radicals. So, it should be a potential antioxidant. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. European bluetongue serotype 8

    NARCIS (Netherlands)

    Drolet, Barbara S.; Reister-Hendricks, Lindsey M.; Podell, Brendan K.; Breitenbach, Jonathan E.; Mcvey, D.S.; Rijn, van Piet A.; Bowen, Richard A.

    2016-01-01

    Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive

  15. An atypical biotype I Actinobacillus pleuropneumoniae serotype 13 is present in North America

    DEFF Research Database (Denmark)

    Perry, Malcolm B.; Angen, Øystein; MacLean, Leann L.

    2012-01-01

    Atypical Actinobacillus pleuropneumoniae serotype 13 strains present in North America are described here for the first time. Different from serotype 13 strains described in Europe, North America strains are biotype I and antigenically related to both, serotypes 13 and 10. Chemical and structural...

  16. Bio-inspired materials engineering using polysaccharide based biotemplates

    International Nuclear Information System (INIS)

    Zollfrank, C.

    2007-01-01

    Nano-structured materials with a controlled microstructure and tailored properties at a scale below 100 nm are of interest for applications in micro-mechanical, sensor and biomedical devices. In contrast to top-down manufacturing processes the formation of solid matter structures in nature is templated and directed by biomacromolecules such as polysaccharides and polypeptides. A promising biomimetic route for the directed deposition of ceramic materials is the application of anisotropically structured biomacromolecules as patterned templates. The polysaccharides exhibit a hierarchical multi scale order as well as self-assembly properties. The bio-inspired deposition and formation of ceramic phases on biomolecular polysaccharide templates was investigated. The polysaccharides were used at various structural levels from the molecular scale up to three-dimensional parts in the millimetre range. The versatility of polysaccharide shaping capabilities was explored using dissolved polysaccharide molecules as well as thin films for the or simultaneous or successive formation of inorganic mineral phases. Microalgae with a spherical appearance of 5 micro-m were applied in mineralisation studies. The extracellular polysaccharide (EPS) layers on the microalgae were used as biotemplates for manufacturing of functional ceramics. The obtained results on the mineralisation of inorganic phases on polysaccharides are adapted for novel biomimetic routes used in the fabrication for functional and biomedical ceramics. (author)

  17. Immunogenicity and Safety of the 13-Valent Pneumococcal Conjugate Vaccine versus the 23-Valent Polysaccharide Vaccine in Unvaccinated HIV-Infected Adults: A Pilot, Prospective Controlled Study.

    Directory of Open Access Journals (Sweden)

    Francesca Lombardi

    Full Text Available Definition of the optimal pneumococcal vaccine strategy in HIV-infected adults is still under evaluation. We aimed to compare immunogenicity and safety of the 13-valent pneumococcal conjugate vaccine (PCV13 versus the 23-valent polysaccharide vaccine (PPSV23 in HIV-infected adults.We performed a pilot, prospective controlled study enrolling HIV-infected pneumococcal vaccine-naïve outpatients, aged 18-65 years with CD4 counts ≥200 cells/μL. Eligible subjects were recruited into two parallel groups: group 1 (n = 50 received two doses of PCV13 eight weeks apart, and group 2 (n = 50 received one dose of PPSV23, as part of their standard of care. Anti-pneumococcal capsular polysaccharide immunoglobulin G concentrations were quantified by ELISA at baseline, 8, 24 and 48 weeks. Clinical and viro-immunological follow-up was performed at the same time points. Unvaccinated, age-matched HIV-negative adults (n = 100 were also enrolled as baseline controls.Pre-vaccination specific IgG titers for each pneumococcal antigen did not differ between study groups but they were constantly lower than those from the HIV-negative controls. After immunization, significant increases in IgG titers were observed in both study groups at each time point compared to baseline, but response to serotype 3 was blunted in group 1. Antibody titers for each antigen did not differ between study groups at week 48. Overall, the proportion of subjects achieving seroprotection and seroconversion to all serotypes was comparable between groups. A marked decrease in IgG levels over time was observed with both vaccines. No relevant adverse reactions were reported in either group.In this population with favorable immune profile, no relevant differences were observed in immunogenicity between PCV13 and PPSV23. Both vaccines were safe and well tolerated.ClinicalTrials.gov NCT02123433.

  18. A DNA Microarray-Based Assay to Detect Dual Infection with Two Dengue Virus Serotypes

    Directory of Open Access Journals (Sweden)

    Alvaro Díaz-Badillo

    2014-04-01

    Full Text Available Here; we have described and tested a microarray based-method for the screening of dengue virus (DENV serotypes. This DNA microarray assay is specific and sensitive and can detect dual infections with two dengue virus serotypes and single-serotype infections. Other methodologies may underestimate samples containing more than one serotype. This technology can be used to discriminate between the four DENV serotypes. Single-stranded DNA targets were covalently attached to glass slides and hybridised with specific labelled probes. DENV isolates and dengue samples were used to evaluate microarray performance. Our results demonstrate that the probes hybridized specifically to DENV serotypes; with no detection of unspecific signals. This finding provides evidence that specific probes can effectively identify single and double infections in DENV samples.

  19. Sequestration of a fluorinated analog of 2,4-dichlorophenol and metabolic products by L. minor as evidenced by 19F NMR

    International Nuclear Information System (INIS)

    Tront, Jacqueline M.; Saunders, F. Michael

    2007-01-01

    Fate of halogenated phenols in plants was investigated using nuclear magnetic resonance (NMR) to identify and quantify contaminants and their metabolites. Metabolites of 4-chloro-2-fluorophenol (4-Cl-2-FP), as well as the parent compound, were detected in acetonitrile extracts using 19 F NMR after various exposure periods. Several fluorinated metabolites with chemical shifts ∼3.5 ppm from the parent compound were present in plant extracts. Metabolites isolated in extracts were tentatively identified as fluorinated-chlorophenol conjugates through examination of signal-splitting patterns and relative chemical shifts. Signal intensity was used to quantify contaminant and metabolite accumulation within plant tissues. The quantity of 4-Cl-2-F metabolites increased with time and mass balance closures of 90-110% were achieved. In addition, solid phase 19 F NMR was used to identify 4-Cl-2-FP which was chemically bound to plant material. This work used 19 F NMR for developing a time series description of contaminant accumulation and transformation in aquatic plant systems. - The aquatic plant L. minor accumulates, sequesters and binds 4-chloro-2-fluorophenol and its metabolites, as was demonstrated using 19 F-NMR

  20. A molecular scheme for Yersinia enterocolitica patho-serotyping derived from genome-wide analysis.

    Science.gov (United States)

    Garzetti, Debora; Susen, Rosa; Fruth, Angelika; Tietze, Erhard; Heesemann, Jürgen; Rakin, Alexander

    2014-05-01

    Yersinia enterocolitica is a food-borne, gastro-intestinal pathogen with world-wide distribution. Only 11 serotypes have been isolated from patients, with O:3, O:9, O:8 and O:5,27 being the serotypes most commonly associated with human yersiniosis. Serotype is an important characteristic of Y. enterocolitica strains, allowing differentiation for epidemiology, diagnosis and phylogeny studies. Conventional serotyping, performed by slide agglutination, is a tedious and laborious procedure whose interpretation tends to be subjective, leading to poor reproducibility. Here we present a PCR-based typing scheme for molecular identification and patho-serotyping of Y. enterocolitica. Genome-wide comparison of Y. enterocolitica sequences allowed analysis of the O-antigen gene clusters of different serotypes, uncovering their formerly unknown genomic locations, and selection of targets for serotype-specific amplification. Two multiplex PCRs and one additional PCR were designed and tested on various reference strains and isolates from different origins. Our genotypic assay proved to be highly specific for identification of Y. enterocolitica species, discrimination between virulent and non-virulent strains, distinguishing the main human-related serotypes, and typing of conventionally untypeable strains. This genotyping scheme could be applied in microbiology laboratories as an alternative or complementary method to the traditional phenotypic assays, providing data for epidemiological studies. Copyright © 2013 Elsevier GmbH. All rights reserved.

  1. Probing spin dynamics and quantum relaxation in Li Y0.998 Ho0.002 F4 via 19F NMR

    Science.gov (United States)

    Graf, M. J.; Lascialfari, A.; Borsa, F.; Tkachuk, A. M.; Barbara, B.

    2006-01-01

    We report measurements of F19 nuclear spin-lattice relaxation 1/T1 as a function of temperature and external magnetic field in a LiY0.998Ho0.002F4 single crystal, a single-ion magnet exhibiting interesting quantum effects. The F19 1/T1 is found to depend on the coupling with the diluted rare-earth (RE) moments, making it an effective probe of the rare-earth spin dynamics. The results for 1/T1 show a behavior similar to that observed in molecular nanomagnets, a result which we attribute to the discreteness of the energy levels in both cases. At intermediate temperatures the lifetime broadening of the crystal field split RE magnetic levels follows a T3 power law. At low temperature the field dependence of 1/T1 shows peaks in correspondence to the critical magnetic fields for energy level crossings (LC). A key result of this study is that the broadening of the levels at LC is found to become extremely small at low temperatures, about 1.7mT , a value which is comparable to the weak dipolar fields at the RE lattice positions. Thus, unlike the molecular magnets, decoherence effects are strongly suppressed, and it may be possible to measure directly the level repulsions at avoided level crossings.

  2. Immobilization of Aspergillus niger F7-02 Lipase in Polysaccharide Hydrogel Beads of Irvingia gabonensis Matrix

    Directory of Open Access Journals (Sweden)

    Safaradeen Olateju Kareem

    2014-01-01

    Full Text Available The potential of polysaccharide Irvingia gabonensis matrix as enzyme immobilization support was investigated. Lipase of Aspergillus niger F7-02 was immobilized by entrapment using glutaraldehyde as the cross-linking agent and stabilized in ethanolic-formaldehyde solution. The pH and temperature stability and activity yield of the immobilized enzyme were determined. Such parameters as enzyme load, bead size, number of beads, and bead reusability were also optimized. Adequate gel strength to form stabilized beads was achieved at 15.52% (w/v Irvingia gabonensis powder, 15% (v/v partially purified lipase, 2.5% (v/v glutaraldehyde, and 3 : 1 (v/v ethanolic-formaldehyde solution. There was 3.93-fold purification when the crude enzyme was partially purified in two-step purification using Imarsil and activated charcoal. Optimum lipase activity 75.3 Ug−1 was achieved in 50 mL test solution containing 15 beads of 7 mm bead size. Relative activity 80% was retained at eight repeated cycles. The immobilization process gave activity yield of 59.1% with specific activity of 12.3 Umg−1 and stabilized at optimum pH 4.5 and temperature 55°C. Thus the effectiveness and cost-efficiency of I. gabonensis as a polymer matrix for lipase immobilization have been established.

  3. Structures of two cell wall-associated polysaccharides of a Streptococcus mitis biovar 1 strain. A unique teichoic acid-like polysaccharide and the group O antigen which is a C-polysaccharide in common with pneumococci

    DEFF Research Database (Denmark)

    Bergström, N; Jansson, P.-E.; Kilian, Mogens

    2000-01-01

    The cell wall of Streptococcus mitis biovar 1 strain SK137 contains the C-polysaccharide known as the common antigen of a closely related species Streptococcus pneumoniae, and a teichoic acid-like polysaccharide with a unique structure. The two polysaccharides are different entities and could...... be partially separated by gel chromatography. The structures of the two polysaccharides were determined by chemical methods and by NMR spectroscopy. The teichoic acid-like polymer has a heptasaccharide phosphate repeating unit with the following structure: The structure neither contains ribitol nor glycerol...... phosphate as classical teichoic acids do, thus we have used the expression teichoic acid-like for this polysaccharide. The following structure of the C-polysaccharide repeating unit was established: where AAT is 2-acetamido-4-amino-2,4, 6-trideoxy-D-galactose. It has a carbohydrate backbone identical...

  4. A kinematically complete, interdisciplinary, and co-institutional measurement of the 19F(α,n) cross section for nuclear safeguards science

    Energy Technology Data Exchange (ETDEWEB)

    Peters, W. A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Smith, M. S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pittman, S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Thompson, S. J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Clement, R. R. C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cizewski, J. A. [Rutgers Univ., New Brunswick, NJ (United States); Pain, S. D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Febbraro, M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Michigan, Ann Arbor, MI (United States); Chipps, K. A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burcher, S. [Rutgers Univ., New Brunswick, NJ (United States); Manning, B. [Rutgers Univ., New Brunswick, NJ (United States); Reingold, C. [Rutgers Univ., New Brunswick, NJ (United States); Avetisyan, R. [Univ. of Notre Dame, IN (United States); Battaglia, A. [Univ. of Notre Dame, IN (United States); Chen, Y. [Univ. of Notre Dame, IN (United States); Long, A. [Univ. of Notre Dame, IN (United States); Lyons, S. [Univ. of Notre Dame, IN (United States); Marley, S. T. [Univ. of Notre Dame, IN (United States); Seymour, C. [Univ. of Notre Dame, IN (United States); Siegl, K. T. [Univ. of Notre Dame, IN (United States); Smith, M. K. [Univ. of Notre Dame, IN (United States); Strauss, S. [Univ. of Notre Dame, IN (United States); Talwar, R. [Univ. of Notre Dame, IN (United States); Bardayan, D. W. [Univ. of Notre Dame, IN (United States); Gyurjinyan, A. [Univ. of Notre Dame, IN (United States); Smith, K. [Univ. of Tennessee, Knoxville, TN (United States); Thornsberry, C.; Thompson, P.; Madurga, M. [Univ. of Tennessee, Knoxville, TN (United States); Stech, E. [Univ. of Notre Dame, IN (United States); Tan, W. P. [Univ. of Notre Dame, IN (United States); Wiescher, M. [Univ. of Notre Dame, IN (United States); Ilyushkin, S. [Colorado School of Mines, Golden, CO (United States); Tully, Z. [Tennessee Technological Univ., Cookeville, TN (United States); Grinder, M. M. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-05-01

    Alpha particles emitted from the decay of uranium in a UF6 matrix can interact with fluorine and generate neutrons via the 19F(α,n)22Na reaction. These neutrons can be used to determine the uranium content in a UF6 storage cylinder. The accuracy of this self-interrogating, non-destructive assay (NDA) technique is, however, limited by the uncertainty of the 19F(α,n)22Na cross section. We have performed complementary measurements of the 19F(α,n)22Na reaction with both 4He and 19F beams to improve the precision of the 19F(α,n)22Na cross section over the alpha energy range that encompasses common actinide alpha decay needed for NDA studies. We have determined an absolute cross section for the 19F(α,n)22Na reaction to an average precision of 7.6% over the alpha energy range of 3.9 – 6.7 MeV. We utilized this cross section in a simulation of a 100 g spherical UF6 assembly and obtained a change in neutron emission rate values of approximately 10-12%, and a significant (factor of 3.6) decrease in the neutron emission rate uncertainty (from 50-51% to 13-14%), compared to simulations using the old cross section. Our new absolute cross section enables improved interpretations of NDAs of containers of arbitrary size and configuration.

  5. Characterization of active polysaccharides of HemoHIM

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kwang Sun; Shin, Myeong Suk; Bae, Beom Seon; Hwang, Yong Cheol [Kyonggi University, Suwon (Korea, Republic of); Ryu, Kwang Won [Chungju University, Chungju (Korea, Republic of)

    2007-07-15

    In this study, we aimed to elucidate the detailed structure and active moiety of polysaccharide, one of the active constituents of immune and hematopoietic modulating activities of HemoHIM. We first isolated the polysaccharide fractions from the hot water extracts of the each ingredient herbs (A. gigas, P. janonica, C. officinale) of HemoHIM and their mixture. These polysaccharides were composed of neutral (85.32-92.73%) and acidic (4.25-7.88%) saccharides, proteins (0.16-4.02%), and polyphenols (2.09-5.37%). The hydrolytic analysis of polysaccharide fractions showed that they commonly showed higher arabinose, galactose, and galacturonic acid contents. These result suggested that these polysaccharides may have higher contents of rhamnogalacturonan among pectic substances and the main active moiety is composed of polysaccharides. The anion exchange chromatography of HemoHIM and each ingredient herb extract using DEAE-Sepharose FF (Cl- form) column resulted in 1 non-adsorption and 8 adsorption fractions. The analysis of immune activity (lymphocyte proliferation) on these fractions showed that the fractions obtained by higher salt concentration carried the higher activity, but all fractions showed considerable immune activity

  6. Characterization of active polysaccharides of HemoHIM

    International Nuclear Information System (INIS)

    Shin, Kwang Sun; Shin, Myeong Suk; Bae, Beom Seon; Hwang, Yong Cheol; Ryu, Kwang Won

    2007-07-01

    In this study, we aimed to elucidate the detailed structure and active moiety of polysaccharide, one of the active constituents of immune and hematopoietic modulating activities of HemoHIM. We first isolated the polysaccharide fractions from the hot water extracts of the each ingredient herbs (A. gigas, P. janonica, C. officinale) of HemoHIM and their mixture. These polysaccharides were composed of neutral (85.32-92.73%) and acidic (4.25-7.88%) saccharides, proteins (0.16-4.02%), and polyphenols (2.09-5.37%). The hydrolytic analysis of polysaccharide fractions showed that they commonly showed higher arabinose, galactose, and galacturonic acid contents. These result suggested that these polysaccharides may have higher contents of rhamnogalacturonan among pectic substances and the main active moiety is composed of polysaccharides. The anion exchange chromatography of HemoHIM and each ingredient herb extract using DEAE-Sepharose FF (Cl- form) column resulted in 1 non-adsorption and 8 adsorption fractions. The analysis of immune activity (lymphocyte proliferation) on these fractions showed that the fractions obtained by higher salt concentration carried the higher activity, but all fractions showed considerable immune activity

  7. Listeria monocytogenes serotype prevalence and biodiversity in diverse food products.

    Science.gov (United States)

    Hadjilouka, Agni; Andritsos, Nikolaos D; Paramithiotis, Spiros; Mataragas, Marios; Drosinos, Eleftherios H

    2014-12-01

    The aim of this study was to assess serotype prevalence and biodiversity of Listeria monocytogenes strains isolated from diverse food products, i.e., minced pork, fruits, and vegetables. Three hundred twenty-six samples previously purchased from supermarkets and street markets within the Athens area were studied for L. monocytogenes prevalence. A total of 121 strains were isolated from the 36 samples that were positive for L. monocytogenes. Serotyping was performed with multiplex PCR, and biodiversity was assessed with random amplified polymorphic DNA (RAPD) PCR analysis using M13, UBC155, and HLWL85 as primers and with repetitive element palindromic (rep) PCR analysis using (GTG)5 as the primer. The majority (17 of 22) of the contaminated minced pork samples contained strains identified as serotype 1/2a, either alone or in combination with strains belonging to serotypes 1/2b, 4a, 4c, or 4ab. However, all L. monocytogenes isolates from fruits and vegetables belonged to serotype 4b. Rep-PCR provided better differentiation of the isolates than did RAPD PCR and resulted in discrimination of the isolates into a larger number of unique profiles. Complete differentiation was achieved only with the combination of these subtyping techniques.

  8. Kinetics of biological decolorisation of anthraquinone based Reactive Blue 19 using an isolated strain of Enterobacter sp.F NCIM 5545.

    Science.gov (United States)

    Holkar, Chandrakant R; Pandit, Aniruddha B; Pinjari, Dipak V

    2014-12-01

    In the present study, an attempt was made to evaluate the bacterial decolorisation of Reactive Blue 19 by an Enterobacter sp.F which was isolated from a mixed culture from anaerobic digester for biogas production. Phenotypic characterization and phylogenetic analysis based on DNA sequencing comparisons indicate that Enterobacter sp.F was 99.7% similar to Enterobacter cloacae ATCC13047. The kinetics of Reactive Blue 19 dye decolorisation by bacterium had been estimated. Effects of substrate concentration, oxygen, temperature, pH, glucose and glucose to microbe weight ratio on the rate of decolorisation were investigated to understand key factor that determines the performance of dye decolorisation. The maximum decolorisation efficiency of Reactive Blue 19 was 90% over period of 24 h for optimized parameter. To the best of our knowledge, this research study is the report where Enterobacter sp.F has been reported with about 90% decolorizing ability against anthraquinone based Reactive Blue 19 dye. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Modified polysaccharides as alternative binders for foundry industry

    Directory of Open Access Journals (Sweden)

    K. Kaczmarska

    2016-10-01

    Full Text Available Polysaccharides constitute a wide group of important polymers with many commercial applications, for example food packaging, fibres, coatings, adhesives etc. This review is devoted to the presentation of polysaccharide application in foundry industry. In this paper the selected properties of foundry moulding sand and core sand containing modified polysaccharides as binders are presented according to foreign literature data. Also, author’s own research about effect of using moulding sand binder consisting of modified polysaccharide (modified starch or its composition with non-toxic synthetic polymers are discussed. Based on technologies taken under consideration in this paper, it could be concluded that polysaccharides are suitable as an alternative for use as binder in foundry moulding applications.

  10. Static and dynamic 18F-FET PET for the characterization of gliomas defined by IDH and 1p/19q status.

    Science.gov (United States)

    Verger, Antoine; Stoffels, Gabriele; Bauer, Elena K; Lohmann, Philipp; Blau, Tobias; Fink, Gereon R; Neumaier, Bernd; Shah, Nadim J; Langen, Karl-Josef; Galldiks, Norbert

    2018-03-01

    The molecular features isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion have gained major importance for both glioma typing and prognosis and have, therefore, been integrated in the World Health Organization (WHO) classification in 2016. The aim of this study was to characterize static and dynamic O-(2- 18 F-fluoroethyl)-L-tyrosine ( 18 F-FET) PET parameters in gliomas with or without IDH mutation or 1p/19q co-deletion. Ninety patients with newly diagnosed and untreated gliomas with a static and dynamic 18 F-FET PET scan prior to evaluation of tumor tissue according to the 2016 WHO classification were identified retrospectively. Mean and maximum tumor-to-brain ratios (TBR mean/max ), as well as dynamic parameters (time-to-peak and slope) of 18 F-FET uptake were calculated. Sixteen (18%) oligodendrogliomas (IDH mutated, 1p/19q co-deleted), 27 (30%) astrocytomas (IDH mutated only), and 47 (52%) glioblastomas (IDH wild type only) were identified. TBR mean , TBR max , TTP and slope discriminated between IDH mutated astrocytomas and IDH wild type glioblastomas (P dynamic 18 F-FET PET parameters may allow determining non-invasively the IDH mutation status. However, IDH mutated and 1p/19q co-deleted oligodendrogliomas cannot be differentiated from glioblastomas and astrocytomas by 18 F-FET PET.

  11. The immunostimulating role of lichen polysaccharides: a review.

    Science.gov (United States)

    Shrestha, Gajendra; St Clair, Larry L; O'Neill, Kim L

    2015-03-01

    The immune system has capacity to suppress the development or progression of various malignancies including cancer. Research on the immunomodulating properties of polysaccharides obtained from plants, microorganisms, marine organisms, and fungi is growing rapidly. Among the various potential sources, lichens, symbiotic systems involving a fungus and an alga and/or a cyanobacterium, show promise as a potential source of immunomodulating compounds. It is well known that lichens produce an abundance of structurally diverse polysaccharides. However, only a limited number of studies have explored the immunostimulating properties of lichen polysaccharides. Published studies have shown that some lichen polysaccharides enhance production of nitrous oxide (NO) by macrophages and also alter the production levels of various proinflammatory and antiinflammatory cytokines (IL-10, IL-12, IL-1β, TNF-α, and IFN-α/β) by macrophages and dendritic cells. Although there are only a limited number of studies examining the role of lichen polysaccharides, all results suggest that lichen polysaccharides can induce immunomodulatory responses in macrophages and dendritic cells. Thus, a detailed evaluation of immunomodulatory capacity of lichen polysaccharides could provide a unique opportunity for the discovery of novel therapeutic agents. Copyright © 2014 John Wiley & Sons, Ltd.

  12. The OsO(3)F(+) and mu-F(OsO(3)F)(2)(+) cations: their syntheses and study by Raman and (19)F NMR spectroscopy and electron structure calculations and X-ray crystal structures of [OsO(3)F][PnF(6)] (Pn = As, Sb), [OsO(3)F][HF](2)[AsF(6)], [OsO(3)F][HF][SbF(6)], and [OsO(3)F][Sb(3)F(16)].

    Science.gov (United States)

    Gerken, Michael; Dixon, David A; Schrobilgen, Gary J

    2002-01-28

    The fluoride ion donor properties of OsO(3)F(2) have been investigated. The salts [OsO(3)F][AsF(6)], [OsO(3)F][HF](2)[AsF(6)], mu-F(OsO(3)F)(2)[AsF(6)], [OsO(3)F][HF](2)[SbF(6)], and [OsO(3)F][HF][SbF(6)] have been prepared by reaction of OsO(3)F(2) with AsF(5) and SbF(5) in HF solvent and have been characterized in the solid state by Raman spectroscopy. The single-crystal X-ray diffraction studies of [OsO(3)F][AsF(6)] (P2(1)/n, a = 7.0001(11) A, c = 8.8629(13) A, beta = 92.270(7) degrees, Z = 4, and R(1) = 0.0401 at -126 degrees C), [OsO(3)F][SbF(6)] (P2(1)/c, a = 5.4772(14) A, b = 10.115(3) A, c = 12.234(3) A, beta = 99.321(5) degrees, Z = 4, and R(1) = 0.0325 at -173 degrees C), [OsO(3)F][HF](2)[AsF(6)] (P2(1)/n, a = 5.1491(9) A, b = 8.129(2) A, c = 19.636(7) A, beta = 95.099(7) degrees, Z = 4, and R(1) = 0.0348 at -117 degrees C), and [OsO(3)F][HF][SbF(6)] (Pc, a = 5.244(4) A, b = 9.646(6) A, c = 15.269(10) A, beta = 97.154(13) degrees, Z = 4, and R(1) = 0.0558 at -133 degrees C) have shown that the OsO(3)F(+) cations exhibit strong contacts to the anions and HF solvent molecules giving rise to cyclic, dimeric structures in which the osmium atoms have coordination numbers of 6. The reaction of OsO(3)F(2) with neat SbF(5) yielded [OsO(3)F][Sb(3)F(16)], which has been characterized by (19)F NMR spectroscopy in SbF(5) and SO(2)ClF solvents and by Raman spectroscopy and single-crystal X-ray diffraction in the solid state (P4(1)m, a = 10.076(6) A, c = 7.585(8) A, Z = 2, and R(1) = 0.0858 at -113 degrees C). The weak fluoride ion basicity of the Sb(3)F(16)(-) anion resulted in an OsO(3)F(+) cation (C(3)(v) point symmetry) that is well isolated from the anion and in which the osmium is four-coordinate. The geometrical parameters and vibrational frequencies of OsO(3)F(+), ReO(3)F, mu-F(OsO(3)F)(2)(+), (FO(3)Os--FPnF(5))(2), and (FO(3)Os--(HF)(2)--FPnF(5))(2) (Pn = As, Sb) have been calculated using density functional theory methods.

  13. The comparative study on screening of pleurotus polysaccharide high-yield strains by use of ion beam implantation and composite mutagenesis

    International Nuclear Information System (INIS)

    Wang Lianfeng; Chen Henglei; Zhang Jun; Zeng Xianxian

    2009-01-01

    In order to screen pleurotus mycelium polysaccharide high-yield strains, the comparative study was made by use of ion beam implantation and composite mutagenesis before screening. The treating mycelium pellet of pleurotus ferulae tentatively with ion beam implantation was performed at the first. Two polysaccharide high-yield strains, PFPH-1and PFPH-2, were selected using fermentation quantitative screening after auxotrophy qualitative primary screening. It has been found that the polysaccharide yield of the mutants is 551.80mg/L and 659.46mg/L respectively,which increases by 46.55% and 75.14% respectively compared to that of initial strain. Then PFPH-1and PFPH-2, as the original strain, is exposed to ultraviolet light and is suffered by additive of LiCl respectively. The results indicate that the polysaccharide yield of strains 1,9 and 10 decreases by 27%, 38% and 37% respectively compared to that of PFPH-1 meanwhile the polysaccharide yield of strain 17 decreases by 28% compared to that of PFPH-2 after high-flux qualitative primary screening. In this study, composite mutagenesis with exposure of ultra-violet and additive of lithium chloride shows some negative effects. (authors)

  14. Evaporation residue excitation function measurement for 19F + 194,198Pt reactions

    International Nuclear Information System (INIS)

    Singh, Varinderjit; Behera, B.R.; Kaur, Maninder

    2012-01-01

    Nuclear dissipation is one of the active fields in the present day nuclear physics research. Experimental signatures for dissipation are observed through large excess in pre-fission neutrons, γ-ray multiplicities from the compound nucleus, giant dipole resonance (GDR) γ-rays, light charged particles and evaporation residues in comparison to standard statistical model, for the heavy-ion induced fusion-fission or fusion-evaporation reactions (ERs). From the analysis of a large set of experimental data, it is well established that there exists a large dissipation at nuclear temperature above 1 MeV. But most of these probes are not sensitive to the dissipation within saddle. The ER cross-section is a probe which is sensitive to dissipation within the saddle point. Hence, the study of ER cross-section can be helpful in estimating the dissipation effects inside the saddle point. Also the other motivation for these measurements is to see the effect of shell closure on dissipation. With this motivation the evaporation cross-sections for 19 F + 194,198 Pt are measured at beam energy of 101 to 137.3 MeV. Of the above systems 19 F + 194 Pt populates 213 Fr (N = 126) shell closed compound nucleus (CN) whereas, other system populate 217 Fr (N = 130) non-shell closed CN

  15. Mapping In Vivo Tumor Oxygenation within Viable Tumor by 19F-MRI and Multispectral Analysis

    Directory of Open Access Journals (Sweden)

    Yunzhou Shi

    2013-11-01

    Full Text Available Quantifying oxygenation in viable tumor remains a major obstacle toward a better understanding of the tumor microenvironment and improving treatment strategies. Current techniques are often complicated by tumor heterogeneity. Herein, a novel in vivo approach that combines 19F magnetic resonance imaging (19F-MRIR1 mapping with diffusionbased multispectral (MS analysis is introduced. This approach restricts the partial pressure of oxygen (pO2 measurements to viable tumor, the tissue of therapeutic interest. The technique exhibited sufficient sensitivity to detect a breathing gas challenge in a xenograft tumor model, and the hypoxic region measured by MS 19F-MRI was strongly correlated with histologic estimates of hypoxia. This approach was then applied to address the effects of antivascular agents on tumor oxygenation, which is a research question that is still under debate. The technique was used to monitor longitudinal pO2 changes in response to an antibody to vascular endothelial growth factor (B20.4.1.1 and a selective dual phosphoinositide 3-kinase/mammalian target of rapamycin inhibitor (GDC-0980. GDC-0980 reduced viable tumor pO2 during a 3-day treatment period, and a significant reduction was also produced by B20.4.1.1. Overall, this method provides an unprecedented view of viable tumor pO2 and contributes to a greater understanding of the effects of antivascular therapies on the tumor's microenvironment.

  16. Epidemiology of Streptococcus pneumoniae causing acute otitis media among children in Southern Catalonia throughout 2007-2013: Incidence, serotype distribution and vaccine's effectiveness.

    Science.gov (United States)

    Ochoa-Gondar, O; Figuerola-Massana, E; Vila-Corcoles, A; Aguirre, C A; de Diego, C; Satue, E; Gomez, F; Raga, X

    2015-12-01

    This study investigated incidence and serotype distribution of Streptococcus pneumoniae causing acute otitis media (AOM) in Catalonian children, evaluating vaccination effectiveness in the current era of extended valency pneumococcal conjugate vaccines (PCVs). Population-based surveillance study that included all AOM cases with isolation of pneumococcus (from otic fluids/otorrea) identified among children ≤14 years in the region of Tarragona (Southern Catalonia, Spain) from 01/01/2007 to 31/12/2013. Prevalence of infections caused by serotypes covered by the different PCVs formulations were calculated for the periods before and after 30/06/2010 (date of PCV7/PCV13 replacement). The indirect cohort method was used to estimate PCV7/13 effectiveness against vaccine-type infections. A total of 78 children with a pneumococcal AOM were identified across study period, which meant an incidence rate of 23 cases per 100,000 population-year. Thirty-six cases (46.2%) occurred within the late PCV7 era and 42 cases (53.8%) during the early PCV13 era. Overall, the most common serotypes were type 19A (21.7%), type 3 (13.3%) and type 15B (6.7%). Prevalence of cases caused by serotypes included in PCV7 did not substantially change between the first and the second study period (from 10.3% to 12.9%), whereas prevalence of cases caused by PCV13 serotypes showed a decreasing trend between both periods (from 65.5% to 48.4%). The aggregate PCV7/13 effectiveness against vaccine-type infections was 72% (95% confidence interval: -26 to 94). Pneumococcal conjugate vaccination appears an acceptable preventive option to prevent pneumococcal AOM in infants. However, its serotype coverage and clinical effectiveness are not optimal. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. [Comparison on polysaccharide content and PMP-HPLC fingerprints of polysaccharide in stems and leaves of Dendrobium officinale].

    Science.gov (United States)

    Zhou, Gui-Fen; Pang, Min-Xia; Chen, Su-Hong; Lv, Gui-Yuan; Yan, Mei-Qiu

    2014-03-01

    In order to provide scientific basics for exploitation and sufficient application of Dendrobium officinale leaves resources, the phenol-sulfuric acid method was applied to determine the polysaccharide content. The monosaccharides were derivated by PMP and the derivatives were identified by HPLC-DAD-ESI-MS(n) and the contents of mannose and glucose were determined simultaneously. Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004A) was employed to generate the mean chromatogram and similarity analysis of the samples was carried out. The results demonstrated that polysaccharide content, monosaccharide compositions and composition ratio had an obvious difference between stems and leaves. The polysaccharide content of stems was higher than that of leaves. Monosaccharide composition in leaf was significantly different from that in stem. The polysaccharide from stems was composed of mannose and glucose, however the polysaccharide of leaves was acid heteropolysaccharide and was mainly composed of five monosaccharides, including mannose, galacturonic acid, glucose, galactose and arabinose. The similarity value of the 14 batches was above 0.9, indicating that similarity of fingerprints among different samples was high. The study can provide evidence for expanding the medicinal parts of D. officinale.

  18. Extraction Optimization, Preliminary Characterization and Bioactivities in Vitro of Ligularia hodgsonii Polysaccharides

    Directory of Open Access Journals (Sweden)

    Xueping Song

    2016-05-01

    Full Text Available The optimization extraction, preliminary characterization and bioactivities of Ligularia hodgsonii polysaccharides were investigated. Based on single-factor experiments and orthogonal array test, the optimum extraction conditions were obtained as follows: extraction time 3 h, temperature 85 °C, water/raw material ratio 36. Further Sevag deproteinization and dialysis yielded the dialyzed Ligularia hodgsonii polysaccharides (DLHP, 19.2 ± 1.4 mg/g crude herb. Compositional analysis, size-exclusion chromatography connected with multi-angle laser light-scattering and refractive index (SEC-MALLS-RI, Fourier transform infrared (FT-IR and 1H nuclear magnetic resonance (NMR spectroscopy were employed for characterization of the polysaccharides. DLHP was found to have a major component with a weight-average molecular weight of 1.17 × 105 Da, mainly comprising of glucose, galactose, arabinose, mannose, rhamnose, glucuronic acid and galacturonic acid. By in vitro antioxidant activity assays, DLHP presented remarkable scavenging capacities towards 1,1-diphenyl-2-picrylhydrazyl (DPPH, 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS and hydroxyl radicals, and ferrous ions chelating ability. Moreover, it exhibited appreciable anti-hyperglycemic activity as demonstrated by differential inhibition of α-glucosidase and α-amylase. The results indicated that DLHP could potentially be a resource for antioxidant and hypoglycemic agents.

  19. In vitro prebiotic effects of seaweed polysaccharides

    Science.gov (United States)

    Chen, Xiaolin; Sun, Yuhao; Hu, Linfeng; Liu, Song; Yu, Huahua; Xing, Rong'e.; Li, Rongfeng; Wang, Xueqin; Li, Pengcheng

    2017-09-01

    Although prebiotic activities of alginate and agar oligosaccharides isolated from seaweeds have been reported, it remains unknown whether seaweed polysaccharides have prebiotic activity. In this study, we isolated polysaccharides from four species of seaweeds, such as Grateloupia filicina (GFP), Eucheuma spinosum (ESP), Ulva pertusa (UPP), and Ascophyllum nodosum (ANP), and characterized their structures and prebiotic effects in vitro. The results showed that these polysaccharides were different in total sugar and sulfate contents as well as monosaccharide composition. GFP and ESP significantly promoted bifidobacterium proliferation and 0.1% ESP and 0.4% GFP resulted in the highest proliferation rates of beneficial bacteria, whereas UPP and ANP inhibited the growth of beneficial bacteria at all tested concentrations (0.1%-0.5%). The different behaviors of the four seaweed-originated polysaccharides might be reflected by differences in monosaccharide composition and structure. Therefore, polysaccharides isolated from GFP and ESP could be utilized as prebiotics. However, more studies must be carried out in vivo.

  20. E2F1-mediated upregulation of p19INK4d determines its periodic expression during cell cycle and regulates cellular proliferation.

    Science.gov (United States)

    Carcagno, Abel L; Marazita, Mariela C; Ogara, María F; Ceruti, Julieta M; Sonzogni, Silvina V; Scassa, María E; Giono, Luciana E; Cánepa, Eduardo T

    2011-01-01

    A central aspect of development and disease is the control of cell proliferation through regulation of the mitotic cycle. Cell cycle progression and directionality requires an appropriate balance of positive and negative regulators whose expression must fluctuate in a coordinated manner. p19INK4d, a member of the INK4 family of CDK inhibitors, has a unique feature that distinguishes it from the remaining INK4 and makes it a likely candidate for contributing to the directionality of the cell cycle. p19INK4d mRNA and protein levels accumulate periodically during the cell cycle under normal conditions, a feature reminiscent of cyclins. In this paper, we demonstrate that p19INK4d is transcriptionally regulated by E2F1 through two response elements present in the p19INK4d promoter. Ablation of this regulation reduced p19 levels and restricted its expression during the cell cycle, reflecting the contribution of a transcriptional effect of E2F1 on p19 periodicity. The induction of p19INK4d is delayed during the cell cycle compared to that of cyclin E, temporally separating the induction of these proliferative and antiproliferative target genes. Specific inhibition of the E2F1-p19INK4d pathway using triplex-forming oligonucleotides that block E2F1 binding on p19 promoter, stimulated cell proliferation and increased the fraction of cells in S phase. The results described here support a model of normal cell cycle progression in which, following phosphorylation of pRb, free E2F induces cyclin E, among other target genes. Once cyclinE/CDK2 takes over as the cell cycle driving kinase activity, the induction of p19 mediated by E2F1 leads to inhibition of the CDK4,6-containing complexes, bringing the G1 phase to an end. This regulatory mechanism constitutes a new negative feedback loop that terminates the G1 phase proliferative signal, contributing to the proper coordination of the cell cycle and provides an additional mechanism to limit E2F activity.

  1. E2F1-mediated upregulation of p19INK4d determines its periodic expression during cell cycle and regulates cellular proliferation.

    Directory of Open Access Journals (Sweden)

    Abel L Carcagno

    Full Text Available BACKGROUND: A central aspect of development and disease is the control of cell proliferation through regulation of the mitotic cycle. Cell cycle progression and directionality requires an appropriate balance of positive and negative regulators whose expression must fluctuate in a coordinated manner. p19INK4d, a member of the INK4 family of CDK inhibitors, has a unique feature that distinguishes it from the remaining INK4 and makes it a likely candidate for contributing to the directionality of the cell cycle. p19INK4d mRNA and protein levels accumulate periodically during the cell cycle under normal conditions, a feature reminiscent of cyclins. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we demonstrate that p19INK4d is transcriptionally regulated by E2F1 through two response elements present in the p19INK4d promoter. Ablation of this regulation reduced p19 levels and restricted its expression during the cell cycle, reflecting the contribution of a transcriptional effect of E2F1 on p19 periodicity. The induction of p19INK4d is delayed during the cell cycle compared to that of cyclin E, temporally separating the induction of these proliferative and antiproliferative target genes. Specific inhibition of the E2F1-p19INK4d pathway using triplex-forming oligonucleotides that block E2F1 binding on p19 promoter, stimulated cell proliferation and increased the fraction of cells in S phase. CONCLUSIONS/SIGNIFICANCE: The results described here support a model of normal cell cycle progression in which, following phosphorylation of pRb, free E2F induces cyclin E, among other target genes. Once cyclinE/CDK2 takes over as the cell cycle driving kinase activity, the induction of p19 mediated by E2F1 leads to inhibition of the CDK4,6-containing complexes, bringing the G1 phase to an end. This regulatory mechanism constitutes a new negative feedback loop that terminates the G1 phase proliferative signal, contributing to the proper coordination of the cell

  2. Emergence of group B Streptococcus serotype IV in women of child-bearing age in Ireland.

    LENUS (Irish Health Repository)

    Kiely, R A

    2011-02-01

    This study determined the carriage rate and serotype distribution of group B Streptococcus (GBS) in women of child-bearing age in the southern region of Ireland. A total of 2000 vaginal swabs collected in two periods in 2004 and 2006 were examined and revealed a GBS carriage rate of 16·1%. Serotyping of isolates showed that serotypes Ia, II, III, IV, and V were the most prevalent. A high prevalence of serotype IV was found, increasing from 7·6% to 15·2% between 2004 and 2006. Random amplified polymorphic DNA analysis demonstrated considerable genetic heterogeneity in the serotype IV isolates. This serotype should be considered for inclusion in potential vaccines for use in Ireland.

  3. Comparison of Toxicological Properties of Botulinum Neurotoxin Serotypes A and B in Mice

    Science.gov (United States)

    Botulinum neurotoxins (BoNTs) are among the most toxic biological toxins for humans. Of the seven known serotypes (A-G) of BoNT, serotypes A, B and E cause most of the human foodborne intoxications. In this study, we compared the toxicological properties of BoNT serotype A and B holotoxins and compl...

  4. Application of 18F-FDG PET/CT combined with carbohydrate antigen 19-9 for differentiating pancreatic carcinoma from chronic mass-forming pancreatitis in Chinese elderly

    Directory of Open Access Journals (Sweden)

    Gu X

    2016-09-01

    Full Text Available Xinjin Gu,1 Rong Liu2 1Department of Hepatobiliary Surgery, Chinese People’s Liberation Army General Hospital and Hainan Branch, Sanya, 2Department of Hepatobiliary and Pancreatic Surgical Oncology, Chinese People’s Liberation Army General Hospital, Beijing, People’s Republic of China Objective: The current study was designed to analyze the value of 18F-FDG positron emission tomography/computed tomography (PET/CT combined with carbohydrate antigen 19-9 (CA19-9 in differentiating pancreatic carcinoma (PC from chronic mass-forming pancreatitis (CMFP in Chinese elderly. Methods: As it is impossible to differentially diagnose PC from CMFP, 60 participants older than 65 years with focal pancreatic lesions were scanned by 18F-FDG PET/CT and their CA19-9 levels were tested. Diagnoses of all participants were confirmed by comprehensive methods including aspiration biopsy, surgical pathology, and clinical follow-up of 12 months. Twenty participants with CMFP were included in CMFP group and 40 participants with PC in PC group.Results: In CMFP and PC groups, 46 participants showed increased 18F-FDG uptake, 43 had elevated CA19-9 levels, and 38 participants had both increased 18F-FDG uptake and elevated CA19-9 levels. Standardized uptake value maximum of PC group (5.98±2.27 was significantly different from CMFP group (2.58±1.81, P<0.05. Sensitivity, specificity, and accuracy of 18F-FDG PET/CT in differentiating PC from CMFP were 95%, 60%, and 83.3%, respectively. CA19-9 levels of PC group (917.44±1,088.24 were significantly different from CMFP group (19.09±19.54, P<0.05. Sensitivity, specificity, and accuracy of CA19-9 levels in differentiating PC from CMFP were 87.5%, 60%, and 78.3%, respectively. Sensitivity, specificity, and accuracy of 18F-FDG PET/CT combined with CA19-9 levels in differentiating PC from CMFP were 90%, 90%, and 90%, respectively.Conclusion: 18F-FDG PET/CT had reliable sensitivity, specificity, and accuracy in differentiating

  5. Population snapshot of Streptococcus pneumoniae causing invasive disease in South Africa prior to introduction of pneumococcal conjugate vaccines.

    Directory of Open Access Journals (Sweden)

    Kedibone M Ndlangisa

    Full Text Available We determined the sequence types of isolates that caused invasive pneumococcal disease (IPD prior to routine use of pneumococcal conjugate vaccines (PCV in South Africa. PCV-13 serotypes and 6C isolates collected in 2007 (1 461/2 437, 60% from patients of all ages as part of on-going, national, laboratory-based surveillance for IPD, were selected for genetic characterization. In addition, all 134 non-PCV isolates from children <2 years were selected for characterization. Sequence type diversity by serotype and age category (children <5 years vs. individuals ≥5 years was assessed for PCV serotypes using Simpson's index of diversity. Similar genotypes circulated among isolates from children and adults and the majority of serotypes were heterogeneous. While globally disseminated clones were common among some serotypes (e.g., serotype 1 [clonal complex (CC 217, 98% of all serotype 1] and 14 [CC230, 43%], some were represented mainly by clonal complexes rarely reported elsewhere (e.g., serotype 3 [CC458, 60%] and 19A [CC2062, 83%]. In children <2 years, serotype 15B and 8 were the most common serotypes among non-PCV isolates (16% [22/134] and 15% [20/134] isolates, respectively. Sequence type 7052 and 53 were most common among serotypes 15B and 8 isolates and accounted for 58% (7/12 and 64% (9/14 of the isolates, respectively. Serotype 19F, 14, 19A and 15B had the highest proportions of penicillin non-susceptible isolates. Genotypes rarely reported in other parts of the world but common among some of our serotypes highlight the importance of our data as these genotypes may emerge post PCV introduction.

  6. Bioactive polysaccharides and gut microbiome (abstract)

    Science.gov (United States)

    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...

  7. Biochemical Aspects of Non-Starch Polysaccharides

    Directory of Open Access Journals (Sweden)

    Rodica Căpriţă

    2010-05-01

    Full Text Available Polysaccharides are macromolecules of monosaccharides linked by glycosidic bonds. Non-starch polysaccharides (NSP are principally non-α-glucan polysaccharides of the plant cell wall. They are a heterogeneous group of polysaccharides with varying degrees of water solubility, size, and structure. The water insoluble fiber fraction include cellulose, galactomannans, xylans, xyloglucans, and lignin, while the water-soluble fibers are the pectins, arabinogalactans, arabinoxylans, and β-(1,3(1,4-D-glucans (β-glucans. Knowledge of the chemical structure of NSP has permitted the development of enzyme technology to overcome their antinutritional effects. The physiological effects of NSP on the digestion and absorption of nutrients in human and monogastric animals have been attributed to their physicochemical properties: hydration properties, viscosity, cation exchange capacity and organic compound absorptive properties. This paper reviews and presents information on NSPs chemistry, physicochemical properties and physiological effects on the nutrient entrapment.

  8. Direct and indirect transmission of four Salmonella enterica serotypes in pigs

    Directory of Open Access Journals (Sweden)

    Österberg Julia

    2010-05-01

    Full Text Available Abstract Background Feed-borne spread of Salmonella spp. to pigs has been documented several times in recent years in Sweden. Experiences from the field suggest that feed-associated serotypes might be less transmittable and subsequently easier to eradicate from pig herds than other serotypes more commonly associated to pigs. Four Salmonella serotypes were selected for experimental studies in pigs in order to study transmissibility and compare possible differences between feed-assoociated (S Cubana and S Yoruba and pig-associated serotypes (S Derby and S Typhimurium. Methods Direct contact transmission was studied in four groups of pigs formed by six 10-week-old salmonella negative pigs commingled with two fatteners excreting one of the four salmonella serotypes. Indirect transmission was studied by putting six 10-week-old salmonella negative pigs in each of four salmonella contaminated rooms. Each room had previously housed a group of pigs, excreting one of the four selected serotypes. All pigs were monitored for two weeks with respect to the faecal excretion of salmonella and the presence of serum antibodies. At the end of the trial, eight samples from inner tissues and organs were collected from each pig at necropsy. Results In the four direct transmission groups, one pig shed Salmonella (Cubana at one occasion. At necropsy, S Typhimurium was isolated from one pig. In the indirect transmission groups, two pigs in the Yoruba room and one pig in each of the other rooms were excreting detectable levels of Salmonella once during the study period of two weeks. At necropsy, S Derby was isolated from one of six pigs in the Derby room and S Typhimurium was isolated from four of the six pigs in the Typhimurium room. No significant serological response could be detected in any of the 48 pigs. Conclusions These results show that all four selected serotypes were able to be transmitted in at least one of these field-like trials, but the transmission rate

  9. Serotyping and analysis of produced pigments kinds by Pseudomonas aeruginosa clinical isolates

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    Stanković-Nedeljković Nataša

    2011-01-01

    Full Text Available Background/Aim. Pseudomonas aeruginosa (P. aeruginosa is devided into 20 serotypes on the base of the International Antigenic Typing Scheme. P. aeruginosa serotyping is important because of few reasons but epidemiological is the most important. The aim of the study was serotyping of P. aeruginosa clinical isolates, analysing of single clinical isolates P. aeruginosa present in the particular samples, and analysing of pyocianin and fluorescin production in different isolates of P. aeruginosa. Methods. A total of 223 isolates of P. aeruginosa, isolated in the microbiological laboratory of the Health Center “Aleksinac”, Aleksinac, were examinated. P. aeruginosa isolates were put on the pseudomonas isolation agar, pseudomonas agar base, acetamid agar, asparagin prolin broth, pseudomonas asparagin broth, Bushnnell-Haas agar, cetrimid agar base, King A and King B plates, plates for pyocianin production, plates for fluorescin production and tripticasa soya agar (Himedia. Polyvalent and monovalent serums were used in the agglutination (Biorad. Pigment production was analysed on the bases of growth on the plates for pyocianin and fluorescin production. Results. Serologically, we identificated the serovars as follows: O1, O3, O4, O5, O6, O7, O8, O10, O11 and O12. O1 (38% was the most often serovar, then O11 (19% and O6 (8.6%. A total of 18.6% (42 isolates did not agglutinate with any serum, whereas 21 isolates agglutinated only with polyvalent serum. The majority of P. aeruginosa isolates produced fluorescin, 129 (58.54%, 53 (22.94% produced pyocianin whereas 49 (21.21% isolates produced both pigments. Conclusion. P. aeruginosa was isolated most of the from urine, sputum and other materials. The majority often serovars were O1, O6 and O11. The most of isolates produced fluorescin (58.54%, while 22.94% producted pyocianin and 21.21% both pigments.

  10. Epigenetic regulation of serotype expression antagonizes transcriptome dynamics in Paramecium tetraurelia.

    Science.gov (United States)

    Cheaib, Miriam; Dehghani Amirabad, Azim; Nordström, Karl J V; Schulz, Marcel H; Simon, Martin

    2015-08-01

    Phenotypic variation of a single genotype is achieved by alterations in gene expression patterns. Regulation of such alterations depends on their time scale, where short-time adaptations differ from permanently established gene expression patterns maintained by epigenetic mechanisms. In the ciliate Paramecium, serotypes were described for an epigenetically controlled gene expression pattern of an individual multigene family. Paradoxically, individual serotypes can be triggered in Paramecium by alternating environments but are then stabilized by epigenetic mechanisms, thus raising the question to which extend their expression follows environmental stimuli. To characterize environmental adaptation in the context of epigenetically controlled serotype expression, we used RNA-seq to characterize transcriptomes of serotype pure cultures. The resulting vegetative transcriptome resource is first analysed for genes involved in the adaptive response to the altered environment. Secondly, we identified groups of genes that do not follow the adaptive response but show co-regulation with the epigenetically controlled serotype system, suggesting that their gene expression pattern becomes manifested by similar mechanisms. In our experimental set-up, serotype expression and the entire group of co-regulated genes were stable among environmental changes and only heat-shock genes altered expression of these gene groups. The data suggest that the maintenance of these gene expression patterns in a lineage represents epigenetically controlled robustness counteracting short-time adaptation processes. © The Author 2015. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  11. Fourth human parechovirus serotype

    NARCIS (Netherlands)

    Benschop, Kimberley S. M.; Schinkel, Janke; Luken, Manon E.; van den Broek, Peter J. M.; Beersma, Matthias F. C.; Menelik, Negassi; van Eijk, Hetty W. M.; Zaaijer, Hans L.; Vandenbroucke-Grauls, Christina M. J. E.; Beld, Marcel G. H. M.; Wolthers, Katja C.

    2006-01-01

    We identified a novel human parechovirus (HPeV) type (K251176-02) from a neonate with fever. Analysis of the complete genome showed K251176-02 to be a new HPeV genotype. Since K251176-02 could not be neutralized with antibodies against known HPeV serotypes 1-3, it should be classified as a fourth

  12. Analytical applications of 19F (p, αγ)16O reaction

    International Nuclear Information System (INIS)

    Arias Revollo, F.R.

    1977-11-01

    The reaction 19 F (p, αγ) 16 O was used to determine fluorine concentration in various substances. A pronounced resonance at E sub(P) = 672 KeV permitted analysis of samples at various depths. Backscattered protons were used to normalize the number of 6,13 and 7,12 MeV gamma rays emitted during sample irradiation. Comparison with gamma/particle ratios from pure substances of know fluorine concentration permits an absolute interpretation of results. The technique was applied to several human and animal tooth samples and fluorine containing minerals. (Author) [pt

  13. Immunomodulatory dietary polysaccharides: a systematic review of the literature

    Directory of Open Access Journals (Sweden)

    Nelson Erika D

    2010-11-01

    Full Text Available Abstract Background A large body of literature suggests that certain polysaccharides affect immune system function. Much of this literature, however, consists of in vitro studies or studies in which polysaccharides were injected. Their immunologic effects following oral administration is less clear. The purpose of this systematic review was to consolidate and evaluate the available data regarding the specific immunologic effects of dietary polysaccharides. Methods Studies were identified by conducting PubMed and Google Scholar electronic searches and through reviews of polysaccharide article bibliographies. Only articles published in English were included in this review. Two researchers reviewed data on study design, control, sample size, results, and nature of outcome measures. Subsequent searches were conducted to gather information about polysaccharide safety, structure and composition, and disposition. Results We found 62 publications reporting statistically significant effects of orally ingested glucans, pectins, heteroglycans, glucomannans, fucoidans, galactomannans, arabinogalactans and mixed polysaccharide products in rodents. Fifteen controlled human studies reported that oral glucans, arabinogalactans, heteroglycans, and fucoidans exerted significant effects. Although some studies investigated anti-inflammatory effects, most studies investigated the ability of oral polysaccharides to stimulate the immune system. These studies, as well as safety and toxicity studies, suggest that these polysaccharide products appear to be largely well-tolerated. Conclusions Taken as a whole, the oral polysaccharide literature is highly heterogenous and is not sufficient to support broad product structure/function generalizations. Numerous dietary polysaccharides, particularly glucans, appear to elicit diverse immunomodulatory effects in numerous animal tissues, including the blood, GI tract and spleen. Glucan extracts from the Trametes versicolor

  14. Detection of Foot-and-mouth Disease Serotype O by ELISA Using a Monoclonal Antibody

    OpenAIRE

    Chen, Hao-tai; Peng, Yun-hua; Zhang, Yong-guang; Liu, Xiang-tao

    2012-01-01

    An ELISA assay with monoclonal antibody (MELISA) was used to type serotype O of foot-and-mouth disease virus (FMDV). All FMDV serotype O reference strains were positive by MELISA, while other viruses such as FMDV serotypes Asia 1, C, and A and classical swine fever virus, swine vesicular disease virus, and porcine reproductive and respiratory syndrome virus remained negative. Furthermore, FMDV serotype O positive samples were able to be detected by MELISA. This assay may be particularly suita...

  15. The Osmium(VIII) Oxofluoro Cations OsO(2)F(3)(+) and F(cis-OsO(2)F(3))(2)(+): Syntheses, Characterization by (19)F NMR Spectroscopy and Raman Spectroscopy, X-ray Crystal Structure of F(cis-OsO(2)F(3))(2)(+)Sb(2)F(11)(-), and Density Functional Theory Calculations of OsO(2)F(3)(+), ReO(2)F(3), and F(cis-OsO(2)F(3))(2)(+).

    Science.gov (United States)

    Casteel, William J.; Dixon, David A.; Mercier, Hélène P. A.; Schrobilgen, Gary J.

    1996-07-17

    Osmium dioxide tetrafluoride, cis-OsO(2)F(4), reacts with the strong fluoride ion acceptors AsF(5) and SbF(5) in anhydrous HF and SbF(5) solutions to form orange salts. Raman spectra are consistent with the formation of the fluorine-bridged diosmium cation F(cis-OsO(2)F(3))(2)(+), as the AsF(6)(-) and Sb(2)F(11)(-) salts, respectively. The (19)F NMR spectra of the salts in HF solution are exchange-averaged singlets occurring at higher frequency than those of the fluorine environments of cis-OsO(2)F(4). The F(cis-OsO(2)F(3))(2)(+)Sb(2)F(11)(-) salt crystallizes in the orthorhombic space group Imma. At -107 degrees C, a = 12.838(3) Å, b = 10.667(2) Å, c = 11.323(2) Å, V = 1550.7(8) Å(3), and Z = 4. Refinement converged with R = 0.0469 [R(w) = 0.0500]. The crystal structure consists of discrete fluorine-bridged F(cis-OsO(2)F(3))(2)(+) and Sb(2)F(11)(-) ions in which the fluorine bridge of the F(cis-OsO(2)F(3))(2)(+) cation is trans to an oxygen atom (Os-O 1.676 Å) of each OsO(2)F(3) group. The angle at the bridge is 155.2(8) degrees with a bridging Os---F(b) distance of 2.086(3) Å. Two terminal fluorine atoms (Os-F 1.821 Å) are cis to the two oxygen atoms (Os-O 1.750 Å), and two terminal fluorine atoms of the OsO(2)F(3) group are trans to one another (1.813 Å). The OsO(2)F(3)(+) cation was characterized by (19)F NMR and by Raman spectroscopy in neat SbF(5) solution but was not isolable in the solid state. The NMR and Raman spectroscopic findings are consistent with a trigonal bipyramidal cation in which the oxygen atoms and a fluorine atom occupy the equatorial plane and two fluorine atoms are in axial positions. Density functional theory calculations show that the crystallographic structure of F(cis-OsO(2)F(3))(2)(+) is the energy-minimized structure and the energy-minimized structures of the OsO(2)F(3)(+) cation and ReO(2)F(3) are trigonal bipyramidal having C(2)(v)() point symmetry. Attempts to prepare the OsOF(5)(+) cation by oxidative fluorination of cis

  16. Protein-observed (19)F-NMR for fragment screening, affinity quantification and druggability assessment.

    Science.gov (United States)

    Gee, Clifford T; Arntson, Keith E; Urick, Andrew K; Mishra, Neeraj K; Hawk, Laura M L; Wisniewski, Andrea J; Pomerantz, William C K

    2016-08-01

    NMR spectroscopy can be used to quantify the binding affinity between proteins and low-complexity molecules, termed 'fragments'; this versatile screening approach allows researchers to assess the druggability of new protein targets. Protein-observed (19)F-NMR (PrOF NMR) using (19)F-labeled amino acids generates relatively simple spectra that are able to provide dynamic structural information toward understanding protein folding and function. Changes in these spectra upon the addition of fragment molecules can be observed and quantified. This protocol describes the sequence-selective labeling of three proteins (the first bromodomains of Brd4 and BrdT, and the KIX domain of the CREB-binding protein) using commercially available fluorinated aromatic amino acids and fluorinated precursors as example applications of the method developed by our research group. Fragment-screening approaches are discussed, as well as Kd determination, ligand-efficiency calculations and druggability assessment, i.e., the ability to target these proteins using small-molecule ligands. Experiment times on the order of a few minutes and the simplicity of the NMR spectra obtained make this approach well-suited to the investigation of small- to medium-sized proteins, as well as the screening of multiple proteins in the same experiment.

  17. Protective effect of plant polysaccharides against radiation injury

    International Nuclear Information System (INIS)

    Wang Bingji; Huang Shafei; Cheng Lurong

    1989-01-01

    A series of polysaccharides have been isolated from Chinese traditional medicinal herbs and tested in mice subjected to ionizing radiation for their protective action. The polysaccharides from different origins showed various degrees of radioprotection. Those isolated from Hericium erinaceus and Armillaria mellea showed a higher radioprotective effect than some other polysaccharides. They could increase the survival rate of irradiated mice to 60%. But the polysaccheride separated from Apocynum venetum has negligible effect. In general, most of these polysaccharides are effective only on administration before irradiation. No apparent protection was observed when given post irradiation. The polysaccharide isolated from Armillaria venetum could raise the survival rate of mice irradiated by lethal dose of γ-rays to 58%. It is effective even when administered after irradiation. Some work has been carried out to clarify the mechanism of radioprotective action of polysaccharides. Protection of hemapoietic organs, regulation of immunological system, induction of release of some endogeneous bioactive substances in the organism and reduction of oxygen tension in some vital tissues may be correlated with the protection of organism against radiation injury

  18. Interaction between gut immunity and polysaccharides.

    Science.gov (United States)

    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.

  19. Biofilm formation capacity of Salmonella serotypes at different temperature conditions

    Directory of Open Access Journals (Sweden)

    Karen A. Borges

    Full Text Available ABSTRACT: Salmonella spp. are one of the most important agents of foodborne disease in several countries, including Brazil. Poultry-derived products are the most common food products, including meat and eggs, involved in outbreaks of human salmonellosis. Salmonella has the capacity to form biofilms on both biotic and abiotic surfaces. The biofilm formation process depends on an interaction among bacterial cells, the attachment surface and environmental conditions. These structures favor bacterial survival in hostile environments, such as slaughterhouses and food processing plants. Biofilms are also a major problem for public health because breakage of these structures can cause the release of pathogenic microorganisms and, consequently, product contamination. The aim of this study was to determine the biofilm production capacity of Salmonella serotypes at four different temperatures of incubation. Salmonella strains belonging to 11 different serotypes, isolated from poultry or from food involved in salmonellosis outbreaks, were selected for this study. Biofilm formation was investigated under different temperature conditions (37°, 28°, 12° and 3°C using a microtiter plate assay. The tested temperatures are important for the Salmonella life cycle and to the poultry-products process. A total of 92.2% of the analyzed strains were able to produce biofilm on at least one of the tested temperatures. In the testing, 71.6% of the strains produced biofilm at 37°C, 63% at 28°C, 52.3% at 12°C and 39.5% at 3°C, regardless of the serotype. The results indicate that there is a strong influence of temperature on biofilm production, especially for some serotypes, such as S. Enteritidis, S. Hadar and S. Heidelberg. The production of these structures is partially associated with serotype. There were also significant differences within strains of the same serotype, indicating that biofilm production capacity may be strain-dependent.

  20. Ultrasonic extraction of polysaccharides from Laminaria japonica and their antioxidative and glycosidase inhibitory activities

    Science.gov (United States)

    Wan, Peng; Yang, Xiaoman; Cai, Bingna; Chen, Hua; Sun, Huili; Chen, Deke; Pan, Jianyu

    2015-08-01

    In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Laminaria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design (BBD) combined with response surface methodology (RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80°C and ratio of material to solvent at 1:50 (g mL-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield (5.75% ± 0.3%) is close to the predicted result (5.67%) with no significant difference ( P > 0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides (LJP) and two major ethanol precipitated fractions (LJP1 and LJP2) are in a concentration-dependent manner. LJP2 (30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase inhibitory activity and moderate scavenging activity against hydroxyl radicals (66.09% ± 2.19%, 3.0 mg mL-1). Also, the inhibitory activity against α-glucosidase (59.08% ± 3.79%, 5.0 mg mL-1) is close to that of acarbose (63.99% ± 3.27%, 5.0 mg mL-1). LJP1 (30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals (99.80% ± 0.00%, 3.0 mg mL-1) and moderate α-glucosidase inhibitory activity (47.76% ± 1.92%, 5.0 mg mL-1). LJP shows the most remarkable DPPH scavenging activity (66.20% ± 0.11%, 5.0 mg mL-1) but weakest α-glucosidase inhibitory activity (37.77% ± 1.30%, 5.0 mg mL-1). However, all these LJPs exert weak inhibitory effects against α-amylase. These results show that UET is an effective method for extracting bioactive polysaccharides from seaweed materials. LJP1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of

  1. NMR 11B, 19F of hydroxofluoroborate solutions in acetic and peracetic acids

    International Nuclear Information System (INIS)

    Shchetinina, G.P.; Brovkina, O.V.; Chernyshov, B.N.

    1985-01-01

    Hydroxofluoroborate solutions in acetic and peracetic acids are studied by the 11 B, 19 F NMR method. The reactions of substitutions of acetate- and peracetate ions for nucleophilic hydroxogroups with the formation of the respective complexes are shown to occur in these solutions, with monodentate coordination of BF 3 CH 3 COO - - and BF 3 CH 3 COOO - - groups being accomplished in this case

  2. Enzymatic method for improving the injectability of polysaccharides. [US Patent Application

    Science.gov (United States)

    Griffith, W.L.; Compere, A.L.; Holleman, J.W.

    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.

  3. Pediatric Invasive Pneumococcal Disease in Guatemala City: Importance of Serotype 2.

    Science.gov (United States)

    Gaensbauer, James T; Asturias, Edwin J; Soto, Monica; Holt, Elizabeth; Olson, Daniel; Halsey, Neal A

    2016-05-01

    To inform estimations of the potential impact of recently introduced pneumococcal conjugate vaccine (PCV), we report results of 11 years of pre-PCV surveillance for invasive pneumococcal disease (IPD) among children in Guatemala City. Cases of IPD in children younger than 5 years were identified by active surveillance at 3 referral hospitals in Guatemala City from October 1996 through 2007. Clinical and demographic data were obtained, and isolates of Streptococcus pneumoniae from normally sterile sites were serotyped using latex agglutination and confirmed by Quellung reaction. Four hundred fifty-two cases of IPD were identified with a case fatality rate of 21%. Meningitis was the most common cause of death (77% of all deaths) and occurred more often in infancy (median age 5 months) than other clinical syndromes. Of the 137 isolates serotyped, type 1 (26 cases, 17%), type 2 (25 cases, 16%) and type 5 (18 cases, 12%) were the most common. Serotype 2 was associated with a higher case fatality rate (28%), higher rate of meningitis (68%) and occurred in younger infants (median age, 3.5 months) than other common serotypes. Recently introduced PCV13 includes 73% of observed serotypes in the study. Infants with IPD presented at a young age. Serotype 2, rarely reported as a significant cause of IPD and not included in available PCVs, was a common cause of disease in this population. PCV13 introduction in Guatemala, begun in 2013, may not have as great an impact in disease reduction as has been observed in other countries.

  4. Static and dynamic 18F-FET PET for the characterization of gliomas defined by IDH and 1p/19q status

    International Nuclear Information System (INIS)

    Verger, Antoine; Stoffels, Gabriele; Lohmann, Philipp; Neumaier, Bernd; Bauer, Elena K.; Blau, Tobias; Fink, Gereon R.; Shah, Nadim J.; Langen, Karl-Josef; Galldiks, Norbert

    2018-01-01

    The molecular features isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion have gained major importance for both glioma typing and prognosis and have, therefore, been integrated in the World Health Organization (WHO) classification in 2016. The aim of this study was to characterize static and dynamic O-(2- 18 F-fluoroethyl)-L-tyrosine ( 18 F-FET) PET parameters in gliomas with or without IDH mutation or 1p/19q co-deletion. Ninety patients with newly diagnosed and untreated gliomas with a static and dynamic 18 F-FET PET scan prior to evaluation of tumor tissue according to the 2016 WHO classification were identified retrospectively. Mean and maximum tumor-to-brain ratios (TBR mean/max ), as well as dynamic parameters (time-to-peak and slope) of 18 F-FET uptake were calculated. Sixteen (18%) oligodendrogliomas (IDH mutated, 1p/19q co-deleted), 27 (30%) astrocytomas (IDH mutated only), and 47 (52%) glioblastomas (IDH wild type only) were identified. TBR mean , TBR max , TTP and slope discriminated between IDH mutated astrocytomas and IDH wild type glioblastomas (P < 0.01). TBR mean showed the best diagnostic performance (cut-off 1.95; sensitivity, 89%; specificity, 67%; accuracy, 81%). None of the parameters discriminated between oligodendrogliomas (IDH mutated, 1p/19q co-deleted) and glioblastomas or astrocytomas. Furthermore, TBR mean , TBR max , TTP, and slope discriminated between gliomas with and without IDH mutation (p < 0.01). The best diagnostic performance was obtained for the combination of TTP with TBR max or slope (accuracy, 73%). Data suggest that static and dynamic 18 F-FET PET parameters may allow determining non-invasively the IDH mutation status. However, IDH mutated and 1p/19q co-deleted oligodendrogliomas cannot be differentiated from glioblastomas and astrocytomas by 18 F-FET PET. (orig.)

  5. A Selective Neutron Detector in the keV Region Utilizing the {sup 19}F (n, gamma) {sup 20}F Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Konijn, J

    1963-05-15

    The Research Swimming-Pool Reactor R2-0 at Studsvik has been used to investigate some resonance and threshold reactions for neutron flux measurements. This reactor, equipped with MTR type fuel elements, has a maximum neutron flux of about 10{sup 12} n/cm{sup 2}/sec, giving a thermal output of 100 kW. A pneumatic rabbit was constructed to bring the samples in activation position, in which there was 15 cm H{sub 2}O and 1.2 cm Al between reactor and foil. A covering, containing 1.22 g {sup 10}B/cm{sup 2} was pushed over the cadmium-covered Al tube of the rabbit. The activation of the foil was measured with a Nal(Tl)-scintillation spectrometer. From the gamma ray spectrum, recorded on a 256 channel pulse height analyzer, the epithermal neutron flux per unit of In E interval was calculated. The activation cross section for {sup 19}F (n, {gamma}) {sup 20}F in the {sup 10}B-covering was computed to be 16 mb, and about 60 % of the induced activity is due to neutrons in the energy range of 20-70 keV. The experimental results were compared with those obtained from the more known resonance reactions {sup 63}Cu (n, {gamma}) {sup 64}Cu and {sup 27}Al (n, {gamma}) {sup 28}Al. The epithermal neutron flux experiments are in good agreement with each other. The fast neutron flux measurements were carried out with the following threshold detectors: {sup 197}Au (n, n') {sup 197m}Au, {sup 58}Ni (n, p) {sup 58}Co, {sup 27}Al (n, p) {sup 27}Mg and {sup 19}F (n, p) {sup 19}O. From these experiments the ratio of {phi}{sub epi}/{phi}{sub fiss} =0.045 {+-} 0.010 is determined at the activation position. The half-life of {sup 197}Au m was determined to 7.35 {+-} 0.25 sec.

  6. Experimental infection of white-tailed deer with bluetongue virus serotype 8

    NARCIS (Netherlands)

    Drolet, B.S.; Reister, L.M.; Mecham, J.O.; Wilson, W.C.; Nol, P.; Vercauteren, K.C.; Rijn, van P.A.; Bowen, R.A.

    2013-01-01

    Bluetongue (BT) is an insect-transmitted, economically important disease of domestic and wild ruminants. Although only five of the 26 reported bluetongue virus (BTV) serotypes are considered endemic to the USA, 10 exotic serotypes have been isolated primarily in the southeastern region of the

  7. Tanks 18 And 19-F Structural Flowable Grout Fill Material Evaluation And Recommendations

    International Nuclear Information System (INIS)

    Stefanko, D.; Langton, C.

    2011-01-01

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: (1) physically stabilize the final landfill by filling the empty volume in the tanks with a non compressible material; (2) provide a barrier for inadvertent intrusion into the tank; (3) reduce contaminant mobility by (a) limiting the hydraulic conductivity of the closed tank and (b) reducing contact between the residual waste and infiltrating water; and (4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: (1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). (2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. (3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix

  8. TANKS 18 AND 19-F STRUCTURAL FLOWABLE GROUT FILL MATERIAL EVALUATION AND RECOMMENDATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Stefanko, D.; Langton, C.

    2011-11-01

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: (1) physically stabilize the final landfill by filling the empty volume in the tanks with a non compressible material; (2) provide a barrier for inadvertent intrusion into the tank; (3) reduce contaminant mobility by (a) limiting the hydraulic conductivity of the closed tank and (b) reducing contact between the residual waste and infiltrating water; and (4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: (1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). (2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. (3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix

  9. Regulation and diversity of plant polysaccharide utilisation in fungi

    NARCIS (Netherlands)

    Battaglia, E.

    2011-01-01

    Filamentous fungi obtain their nutrients by degrading dead or living plant material. Plant material consists of different cell wall and storage polysaccharides. Due to the complex structure and the variety of plant polysaccharides, filamentous fungi secrete a wide range of plant polysaccharide

  10. Identification of Actinobacillus pleuropneumoniae serotypes 1, 7, and 12 by multiplex PCR based on genes involved in encapsulation

    DEFF Research Database (Denmark)

    Angen, Øystein; Jessing, Stine Graakjær; Ahrens, Peter

    2005-01-01

    . However, a number of isolates show cross-reaction between serotypes and this has urged the development of quick, serotype specific DNA-based methods necessary. Serotype specific tests have until now been described for the serotypes 2, 5, and 6 (Jessing et al, 2003) and serotypes 1, 2 and 8 (Schuchert et...

  11. Comparative genomic analysis uncovers 3 novel loci encoding type six secretion systems differentially distributed in Salmonella serotypes

    Directory of Open Access Journals (Sweden)

    Santiviago Carlos A

    2009-08-01

    Full Text Available Abstract Background The recently described Type VI Secretion System (T6SS represents a new paradigm of protein secretion in bacteria. A number of bioinformatic studies have been conducted to identify T6SS gene clusters in the available bacterial genome sequences. According to these studies, Salmonella harbors a unique T6SS encoded in the Salmonella Pathogenicity Island 6 (SPI-6. Since these studies only considered few Salmonella genomes, the present work aimed to identify novel T6SS loci by in silico analysis of every genome sequence of Salmonella available. Results The analysis of sequencing data from 44 completed or in progress Salmonella genome projects allowed the identification of 3 novel T6SS loci. These clusters are located in differentially-distributed genomic islands we designated SPI-19, SPI-20 and SPI-21, respectively. SPI-19 was identified in a subset of S. enterica serotypes including Dublin, Weltevreden, Agona, Gallinarum and Enteritidis. In the later, an internal deletion eliminated most of the island. On the other hand, SPI-20 and SPI-21 were restricted to S. enterica subspecies arizonae (IIIa serotype 62:z4,z23:-. Remarkably, SPI-21 encodes a VgrG protein containing a C-terminal extension similar to S-type pyocins of Pseudomonas aeruginosa. This is not only the first evolved VgrG described in Salmonella, but also the first evolved VgrG including a pyocin domain described so far in the literature. In addition, the data indicate that SPI-6 T6SS is widely distributed in S. enterica and absent in serotypes Enteritidis, Gallinarum, Agona, Javiana, Paratyphi B, Virchow, IIIa 62:z4,z23:- and IIIb 61:1,v:1,5,(7. Interestingly, while some serotypes harbor multiple T6SS (Dublin, Weltvreden and IIIa 62:z4,z23:- others do not encode for any (Enteritidis, Paratyphi B, Javiana, Virchow and IIIb 61:1,v:1,5,(7. Comparative and phylogenetic analyses indicate that the 4 T6SS loci in Salmonella have a distinct evolutionary history. Finally, we

  12. Radiation degradation of marine polysaccharides by low energy electron beam

    International Nuclear Information System (INIS)

    Yoshii, Fumio; Nagasawa, Naotsugu; Kume, Tamikazu

    2003-01-01

    The radiation degradations of marine polysaccharides by both gamma Co-60 and electron beam irradiations are investigated. Polysaccharides and oligosaccharides can be produced by degradation of corresponding polysaccharides including marine polysaccharides such as alginates, chitin chitosan and carrageenan. The viscosity of alginate, chitosan and carrageenan solution decreases markedly with increase of the low energy electron beam irradiation time and the beam current. Furthermore, the viscosity is reduced sharply in short time for polysaccharide solution with low concentration, for instance carrageenan solution of 1%. (author)

  13. Fragment-Linking Approach Using (19)F NMR Spectroscopy To Obtain Highly Potent and Selective Inhibitors of β-Secretase.

    Science.gov (United States)

    Jordan, John B; Whittington, Douglas A; Bartberger, Michael D; Sickmier, E Allen; Chen, Kui; Cheng, Yuan; Judd, Ted

    2016-04-28

    Fragment-based drug discovery (FBDD) has become a widely used tool in small-molecule drug discovery efforts. One of the most commonly used biophysical methods in detecting weak binding of fragments is nuclear magnetic resonance (NMR) spectroscopy. In particular, FBDD performed with (19)F NMR-based methods has been shown to provide several advantages over (1)H NMR using traditional magnetization-transfer and/or two-dimensional methods. Here, we demonstrate the utility and power of (19)F-based fragment screening by detailing the identification of a second-site fragment through (19)F NMR screening that binds to a specific pocket of the aspartic acid protease, β-secretase (BACE-1). The identification of this second-site fragment allowed the undertaking of a fragment-linking approach, which ultimately yielded a molecule exhibiting a more than 360-fold increase in potency while maintaining reasonable ligand efficiency and gaining much improved selectivity over cathepsin-D (CatD). X-ray crystallographic studies of the molecules demonstrated that the linked fragments exhibited binding modes consistent with those predicted from the targeted screening approach, through-space NMR data, and molecular modeling.

  14. Magnetism in multiferroic Pb.sub.5./sub.Cr.sub.3./sub.F.sub.19./sub..

    Czech Academy of Sciences Publication Activity Database

    Blinc, R.; Cevc, P.; Tavčar, G.; Žemva, B.; Laguta, Valentyn; Trontelj, Z.; Jagodič, M.; Pajič, D.; Balcytis, A.; Scott, J.F.

    2012-01-01

    Roč. 85, č. 5 (2012), "054419-1"-"054419-5" ISSN 1098-0121 Institutional research plan: CEZ:AV0Z10100521 Keywords : multiferroic * magnetism * ferroelectricity * magnetic resonance * Pb 5 Cr 3 F 19 Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.767, year: 2012

  15. Structure of a shear-thickening polysaccharide extracted from the New Zealand black tree fern, Cyathea medullaris.

    Science.gov (United States)

    Wee, May S M; Matia-Merino, Lara; Carnachan, Susan M; Sims, Ian M; Goh, Kelvin K T

    2014-09-01

    A shear-thickening water-soluble polysaccharide was purified from mucilage extracted from the fronds of the New Zealand black tree fern (Cyathea medullaris or 'mamaku' in Māori) and its structure characterised. Constituent sugar analysis by three complementary methods, combined with linkage analysis (of carboxyl reduced samples) and 1H and 13C nuclear magnetic resonance spectroscopy (NMR) revealed a glucuronomannan comprising a backbone of 4-linked methylesterified glucopyranosyl uronic acid and 2-linked mannopyranosyl residues, branched at O-3 of 45% and at both O-3 and O-4 of 53% of the mannopyranosyl residues with side chains likely comprising terminal xylopyranosyl, terminal galactopyranosyl, non-methylesterified terminal glucopyranosyl uronic acid and 3-linked glucopyranosyl uronic acid residues. The weight-average molecular weight of the purified polysaccharide was ∼1.9×10(6) Da as determined by size-exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS). The distinctive rheological properties of this polysaccharide are discussed in relation to its structure. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Highly hindered 2-(aryl-di-tert-butylsilyl)-N-methyl-imidazoles: a new tool for the aqueous 19F- and 18F-fluorination of biomolecule-based structures.

    Science.gov (United States)

    Tisseraud, Marion; Schulz, Jürgen; Vimont, Delphine; Berlande, Murielle; Fernandez, Philippe; Hermange, Philippe; Fouquet, Eric

    2018-05-01

    A new class of silicon-based fluoride acceptors with a C-linked heterocycle as the leaving group was synthesized in one step from commercial chemicals, and linked to biomolecules. The resulting conjugates were efficiently 19F-fluorinated in aqueous mixtures, and switching to 18F-labelling provided nucleoside- and peptide-based bioconjugates with excellent molar activities suitable for biological applications.

  17. pH-Dependent spin state population and 19F NMR chemical shift via remote ligand protonation in an iron(ii) complex.

    Science.gov (United States)

    Gaudette, Alexandra I; Thorarinsdottir, Agnes E; Harris, T David

    2017-11-30

    An Fe II complex that features a pH-dependent spin state population, by virtue of a variable ligand protonation state, is described. This behavior leads to a highly pH-dependent 19 F NMR chemical shift with a sensitivity of 13.9(5) ppm per pH unit at 37 °C, thereby demonstrating the potential utility of the complex as a 19 F chemical shift-based pH sensor.

  18. Biofilm-Forming Abilities of Listeria monocytogenes Serotypes Isolated from Different Sources

    Science.gov (United States)

    Doijad, Swapnil P.; Barbuddhe, Sukhadeo B.; Garg, Sandeep; Poharkar, Krupali V.; Kalorey, Dewanand R.; Kurkure, Nitin V.; Rawool, Deepak B.; Chakraborty, Trinad

    2015-01-01

    A total of 98 previously characterized and serotyped L. monocytogenes strains, comprising 32 of 1/2a; 20 of 1/2b and 46 of 4b serotype, from clinical and food sources were studied for their capability to form a biofilm. The microtiter plate assay revealed 62 (63.26%) strains as weak, 27 (27.55%) strains as moderate, and 9 (9.18%) strains as strong biofilm formers. Among the strong biofilm formers, 6 strains were of serotype 1/2a and 3 strains were of serotype 1/2b. None of the strain from 4b serotype exhibited strong biofilm formation. No firm correlation (p = 0.015) was noticed between any serotype and respective biofilm formation ability. Electron microscopic studies showed that strong biofilm forming isolates could synthesize a biofilm within 24 h on surfaces important in food industries such as stainless steel, ceramic tiles, high-density polyethylene plastics, polyvinyl chloride pipes, and glass. Cell enumeration of strong, moderate, and weak biofilm was performed to determine if the number of cells correlated with the biofilm-forming capabilities of the isolates. Strong, moderate, and weak biofilm showed 570±127× 103 cells/cm2, 33±26× 103 cells/cm2, 5±3× 103 cells/cm2, respectively, indicating that the number of cells was directly proportional to the strength of the biofilm. The hydrophobicity index (HI) analysis revealed higher hydrophobicity with an increased biofilm formation. Fatty acid methyl esterase analysis revealed the amount of certain fatty acids such as iso-C15:0, anteiso-C15:0, and anteiso-C17:0 fatty acids correlated with the biofilm-forming capability of L. monocytogenes. This study showed that different strains of L. monocytogenes form biofilm of different intensities which did not completely correlate with their serotype; however, it correlated with the number of cells, hydrophobicity, and amount of certain fatty acids. PMID:26360831

  19. Biofilm-Forming Abilities of Listeria monocytogenes Serotypes Isolated from Different Sources.

    Directory of Open Access Journals (Sweden)

    Swapnil P Doijad

    Full Text Available A total of 98 previously characterized and serotyped L. monocytogenes strains, comprising 32 of 1/2a; 20 of 1/2b and 46 of 4b serotype, from clinical and food sources were studied for their capability to form a biofilm. The microtiter plate assay revealed 62 (63.26% strains as weak, 27 (27.55% strains as moderate, and 9 (9.18% strains as strong biofilm formers. Among the strong biofilm formers, 6 strains were of serotype 1/2a and 3 strains were of serotype 1/2b. None of the strain from 4b serotype exhibited strong biofilm formation. No firm correlation (p = 0.015 was noticed between any serotype and respective biofilm formation ability. Electron microscopic studies showed that strong biofilm forming isolates could synthesize a biofilm within 24 h on surfaces important in food industries such as stainless steel, ceramic tiles, high-density polyethylene plastics, polyvinyl chloride pipes, and glass. Cell enumeration of strong, moderate, and weak biofilm was performed to determine if the number of cells correlated with the biofilm-forming capabilities of the isolates. Strong, moderate, and weak biofilm showed 570±127× 103 cells/cm2, 33±26× 103 cells/cm2, 5±3× 103 cells/cm2, respectively, indicating that the number of cells was directly proportional to the strength of the biofilm. The hydrophobicity index (HI analysis revealed higher hydrophobicity with an increased biofilm formation. Fatty acid methyl esterase analysis revealed the amount of certain fatty acids such as iso-C15:0, anteiso-C15:0, and anteiso-C17:0 fatty acids correlated with the biofilm-forming capability of L. monocytogenes. This study showed that different strains of L. monocytogenes form biofilm of different intensities which did not completely correlate with their serotype; however, it correlated with the number of cells, hydrophobicity, and amount of certain fatty acids.

  20. Verification of threshold activation detection (TAD) technique in prompt fission neutron detection using scintillators containing 19F

    Science.gov (United States)

    Sibczynski, P.; Kownacki, J.; Moszyński, M.; Iwanowska-Hanke, J.; Syntfeld-Każuch, A.; Gójska, A.; Gierlik, M.; Kaźmierczak, Ł.; Jakubowska, E.; Kędzierski, G.; Kujawiński, Ł.; Wojnarowicz, J.; Carrel, F.; Ledieu, M.; Lainé, F.

    2015-09-01

    In the present study ⌀ 5''× 3'' and ⌀ 2''× 2'' EJ-313 liquid fluorocarbon as well as ⌀ 2'' × 3'' BaF2 scintillators were exposed to neutrons from a 252Cf neutron source and a Sodern Genie 16GT deuterium-tritium (D+T) neutron generator. The scintillators responses to β- particles with maximum endpoint energy of 10.4 MeV from the n+19F reactions were studied. Response of a ⌀ 5'' × 3'' BC-408 plastic scintillator was also studied as a reference. The β- particles are the products of interaction of fast neutrons with 19F which is a component of the EJ-313 and BaF2 scintillators. The method of fast neutron detection via fluorine activation is already known as Threshold Activation Detection (TAD) and was proposed for photofission prompt neutron detection from fissionable and Special Nuclear Materials (SNM) in the field of Homeland Security and Border Monitoring. Measurements of the number of counts between 6.0 and 10.5 MeV with a 252Cf source showed that the relative neutron detection efficiency ratio, defined as epsilonBaF2 / epsilonEJ-313-5'', is 32.0% ± 2.3% and 44.6% ± 3.4% for front-on and side-on orientation of the BaF2, respectively. Moreover, the ⌀ 5'' EJ-313 and side-on oriented BaF2 were also exposed to neutrons from the D+T neutron generator, and the relative efficiency epsilonBaF2 / epsilonEJ-313-5'' was estimated to be 39.3%. Measurements of prompt photofission neutrons with the BaF2 detector by means of data acquisition after irradiation (out-of-beam) of nuclear material and between the beam pulses (beam-off) techniques were also conducted on the 9 MeV LINAC of the SAPHIR facility.

  1. Polysaccharides and paramagnetic ions as a model for the relaxation behavior of hypointense cysts of the head and neck in MR imaging

    International Nuclear Information System (INIS)

    Gibby, W.A.; Hackney, D.B.; Bilaniuk, L.T.; Zimmerman, R.A.; Bogdan, A.R.

    1988-01-01

    Marked hypointensity on the second echo of long repetition time (TR) pulse sequences at 1.5 T has been noted in colloid cysts of the third ventricle and mucous retention cysts of the sinuses. Both are lesions containing a large quantity of material that stains positive for polysaccharide. In an attempt to explain these findings, polysaccharide materials (potato starch) were prepared at 1%, 3%, and 7% (liquid) and 10% (gel) concentrations in distilled deionized water, .01 and .1m mM FeCl3. Imaging at 1.5 T and measurements of T1 and T2 at 1.9 T were performed. Relaxation rates of 10% dextran solutions with average molecular weights of 17,000, 40,000, 70,000, 150,000 and 450,0000 were measured at 1.9 T. The addition of 1% - 10% starch to water shortened T1 and increased the brightness of images obtained at short TR/TE. The addition of FeCl3 increased T1 shortening and image brightness with T1 weighting. T2 was minimally affected by the soluble polysaccharide, but somewhat more decreased in the gelatinous material

  2. Plant-Polysaccharide-Degrading Enzymes from Basidiomycetes

    Science.gov (United States)

    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

  3. Anti-radiation effect of hericium erinaceus polysaccharide

    International Nuclear Information System (INIS)

    Liu Shuchen; Zhang Huijuan; Luo Chuanhuan; Wang Bingji

    1999-01-01

    Objective: To study the anti-radiation effect of hericium erinaceus polysaccharide on irradiated mice. Methods: 520 female mice were randomized to several groups and exposed to 6.25-8.5 Gy whole-body γ-rays. The hericium erinaceus polysaccharide was injected i.p before or after irradiation. The 30-day survival rate of mice was determined, and DNA content of bone marrow was observed as well at seventh day after irradiation. Results: It was showed that the 30-day survival rate and DNA content of bone marrow were all significantly higher in 30 mg or 15 mg hericium erinaceus polysaccharide-treated groups than those in the corresponding irradiated controls (P < 0.01). The 30-day survival rate increased from 35% to 97.5%. Conclusion: The hericium erinaceus polysaccharide has marked anti-radiation effect. Further investigation is worthwhile

  4. Probiotic bacteria inhibit the bovine respiratory pathogen Mannheimia haemolytica serotype 1 in vitro.

    Science.gov (United States)

    Amat, S; Subramanian, S; Timsit, E; Alexander, T W

    2017-05-01

    This study evaluated the potential of probiotic bacteria to inhibit growth and cell adhesion of the bovine respiratory pathogen Mannheimia haemoltyica serotype 1. The inhibitory effects of nine probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus helveticus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis, Streptococcus thermophilus and two Paenibacillus polymyxa strains) against M. haemolytica were evaluated using a spot-on-lawn method. Probiotic strains were then tested for their adherence to bovine bronchial epithelial (BBE) cells and the ability to displace and compete against M. haemolytica on BBE. Except for S. thermophilus, all probiotic strains inhibited the growth of M. haemolytica, with zones of inhibition ranging between 12 and 19 mm. Lactobacillus strains and Lactococcus lactis displayed greater (P probiotics (probiotics. The results of this study suggest that probiotics may have the potential to colonize the bovine respiratory tract, and exert antagonistic effects against M. haemolytica serotype 1. A common method to control bovine respiratory disease (BRD) in feedlots is through mass medication with antibiotics upon cattle entry (i.e. metaphylaxis). Increasingly, antimicrobial resistance in BRD bacterial pathogens has been observed in feedlots, which may have important implications for cattle health. In this study, probiotic strains were shown to adhere to bovine respiratory cells and inhibit the BRD pathogen M. haemolytica serotype 1 through competition and displacement. Probiotics may therefore offer a mitigation strategy to reduce BRD bacterial pathogens, in place of metaphylactic antimicrobials. © 2017 Her Majesty the Queen in Right of Canada Letters in Applied Microbiology © 2017 The Society for Applied Microbiology Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada.

  5. Serotypes and Antimicrobial Susceptibility of Salmonella spp. Isolated from Farm Animals in China

    Directory of Open Access Journals (Sweden)

    Yuan Zong Hui

    2015-06-01

    Full Text Available Salmonella spp. can indirectly infect humans via transfer from animals and animal-derived food products, and thereby cause potentially fatal diseases. Therefore, gaining an understanding of Salmonella infection in farm animals is increasingly important. The aim of this study was to identify the distribution of serotypes in Salmonella samples isolated from chickens (n = 837, pigs (n = 930, and dairy cows (n = 418 in central China (Henan, Hubei, and Hunan provinces in 2010–2011, and investigate the susceptibility of strains to antimicrobial agents. Salmonella isolates were identified by PCR amplification of the invA gene, serotypes were determined by using a slide agglutination test for O and H antigens, and susceptibility to 24 antimicrobials was tested using the agar dilution method. In total, 248 Salmonella strains were identified: 105, 105, and 38 from chickens, dairy cows, and pigs, respectively. Additionally, 209 strains were identified in unhealthy pigs from the Huazhong Agricultural University veterinary hospital. Among these 457 strains, the dominant serotypes were Typhimurium in serogroup B, IIIb in serogroup C, and Enteritidis in serogroup D. In antimicrobial susceptibility tests, 41.14% of Salmonella spp. were susceptible to all antimicrobial agents, 48.14% were resistant to at least one, and 34.72% were resistant to more than three classes. Strains were highly resistant to sulfamethoxazole-trimethoprim (39.61%, nalidixic acid (39.17%, doxycycline (28.22%, and tetracycline (27.58%. Resistance to cephalosporins and fluoroquinolones ranged from 5.25% to 7.44% and 19.04% to 24.51%, respectively. Among penicillin-resistant and cephalosporin-resistant strains, 25 isolates produced extended-spectrum β-lactamases (ESBLs. The multidrug-resistant and ESBL-producing Salmonella strains identified in healthy animals here will present a challenge for veterinary medicine and farm animal husbandry, and could also pose a threat to public health

  6. Genomic characterization of Flavobacterium psychrophilum serotypes and development of a multiplex PCR-based serotyping scheme

    DEFF Research Database (Denmark)

    Rochat, Tatiana; Fujiwara-Nagata, Erina; Calvez, Ségolène

    2017-01-01

    Flavobacterium psychrophilum is a devastating bacterial pathogen of salmonids reared in freshwater worldwide. So far, serological diversity between isolates has been described but the underlying molecular factors remain unknown. By combining complete genome sequence analysis and the serotyping me...... for bacterial coldwater disease resistance and future vaccine formulation....

  7. Differential effects of viroporin inhibitors against feline infectious peritonitis virus serotypes I and II.

    Science.gov (United States)

    Takano, Tomomi; Nakano, Kenta; Doki, Tomoyoshi; Hohdatsu, Tsutomu

    2015-05-01

    Feline infectious peritonitis virus (FIP virus: FIPV), a feline coronavirus of the family Coronaviridae, causes a fatal disease called FIP in wild and domestic cat species. The genome of coronaviruses encodes a hydrophobic transmembrane protein, the envelope (E) protein. The E protein possesses ion channel activity. Viral proteins with ion channel activity are collectively termed "viroporins". Hexamethylene amiloride (HMA), a viroporin inhibitor, can inhibit the ion channel activity of the E protein and replication of several coronaviruses. However, it is not clear whether HMA and other viroporin inhibitors affect replication of FIPV. We examined the effect of HMA and other viroporin inhibitors (DIDS [4,4'-disothiocyano-2,2'-stilbenedisulphonic acid] and amantadine) on infection by FIPV serotypes I and II. HMA treatment drastically decreased the titers of FIPV serotype I strains Black and KU-2 in a dose-dependent manner, but it only slightly decreased the titer of FIPV serotype II strain 79-1146. In contrast, DIDS treatment decreased the titer of FIPV serotype II strain 79-1146 in dose-dependent manner, but it only slightly decreased the titers of FIPV serotype I strains Black and KU-2. We investigated whether there is a difference in ion channel activity of the E protein between viral serotypes using E. coli cells expressing the E protein of FIPV serotypes I and II. No difference was observed, suggesting that a viroporin other than the E protein influences the differences in the actions of HMA and DIDS on FIPV serotypes I and II.

  8. Visualization of bacterial polysaccharides by scanning transmission electron microscopy.

    Science.gov (United States)

    Wolanski, B S; McAleer, W J; Hilleman, M R

    1983-04-01

    Highly purified capsular polysaccharides of Neisseria meningitidis groups A, B, and C have been visualized by high resolution Scanning Transmission Electron Microscopy (STEM). Spheroidal macromolecules approximately 200 A in diameter are characteristic of the Meningococcus A and C polysaccharides whereas filaments that are 400-600 A in length are found in Meningococcus B polysaccharide preparations. Filaments are occasionally found associated with the spheroidal Meningococcus A and C polysaccharides and it is proposed that these structures are composed of a long (1-4 microns) filament or filaments that are arranged in spheroidal molecules or micelles of high molecular weight. The Meningococcus B polysaccharide, by contrast, is a short flexuous filament or strand of relatively low molecular weight. A relationship between morphology and antigenicity is proposed.

  9. Herpes simplex virus serotype and entry receptor availability alter CNS disease in a mouse model of neonatal HSV.

    Science.gov (United States)

    Kopp, Sarah J; Ranaivo, Hantamalala R; Wilcox, Douglas R; Karaba, Andrew H; Wainwright, Mark S; Muller, William J

    2014-12-01

    Outcomes of neonates with herpes simplex virus (HSV) encephalitis are worse after infection with HSV-2 when compared with HSV-1. The proteins herpes virus entry mediator (HVEM) and nectin-1 mediate HSV entry into susceptible cells. Prior studies have shown receptor-dependent differences in pathogenesis that depend on route of inoculation and host developmental age. We investigated serotype-related differences in HSV disease and their relationship to entry receptor availability in a mouse model of encephalitis. Mortality was attenuated in 7-d-old, wild-type (WT) mice inoculated with HSV-1(F) when compared with HSV-2(333). No serotype-specific differences were seen after inoculation of adult mice. HSV-1 pathogenesis was also attenuated relative to HSV-2 in newborn but not adult mice lacking HVEM or nectin-1. HSV-2 requires nectin-1 for encephalitis in adult but not newborn mice; in contrast, nectin-1 was important for HSV-1 pathogenesis in both age groups. Early viral replication was independent of age, viral serotype, or mouse genotype, suggesting host responses influence outcomes. In this regard, significantly greater amounts of inflammatory mediators were detected in brain homogenates from WT newborns 2 d after infection compared with adults and receptor-knockout newborns. Dysregulation of inflammatory responses induced by infection may influence the severity of HSV encephalitis.

  10. Chemical studies on the polysaccharides of Salicornia brachiata.

    Science.gov (United States)

    Sanandiya, Naresh D; Siddhanta, A K

    2014-11-04

    A group of 12 polysaccharide extracts were prepared from the tips, stem and roots of an Indian halophyte Salicornia brachiata Roxb. obtained by sequential extractions with cold water (CW), hot water (HW), aqueous ammonium oxalate (OX) and aqueous sodium hydroxide (ALK) solutions. Monosaccharide composition analysis revealed that all the polysaccharide extract samples consisted primarily of rhamnose, arabinose, mannose, galactose, glucose, whereas ribose and xylose were present only in some of the extracts. All the extracts exhibited low apparent viscosity (1.47-2.02 cP) and sulphate and contained no prominent toxic metal ions. Fucose was detected only in OX extract of the roots. These polysaccharides were found to be heterogeneous and highly branched (glycoside linkage analysis, size-exclusion chromatography, (13)C-NMR, FT-IR, circular dichroism and optical rotation data). Physico-chemical analyses of these polysaccharides including uronic acid, sulphate and protein contents were also carried out. This constitutes the first report on the profiling of Salicornia polysaccharides. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Comparison of polysaccharides from two species of Ganoderma.

    Science.gov (United States)

    Xie, Jing; Zhao, Jing; Hu, De-Jun; Duan, Jin-Ao; Tang, Yu-Ping; Li, Shao-Ping

    2012-01-13

    Ganoderma lucidum and Ganoderma sinense, known as Lingzhi in Chinese, are commonly used Chinese medicines with excellent beneficial health effects. Triterpenes and polysaccharides are usually considered as their main active components. However, the content of triterpenes differs significantly between the two species of Ganoderma. To date, a careful comparison of polysaccharides from the two species of Ganoderma has not been performed. In this study, polysaccharides from fruiting bodies of two species of Lingzhi collected from different regions of China were analyzed and compared based on HPSEC-ELSD and HPSEC-MALLS-RI analyses, as well as enzymatic digestion and HPTLC of acid hydrolysates. The results indicated that both the HPSEC-ELSD profiles and the molecular weights of the polysaccharides were similar. Enzymatic digestion showed that polysaccharides from all samples of Lingzhi could be hydrolyzed by pectinase and dextranase. HPTLC profiles of their TFA hydrolysates colored with different reagents and their monosaccharides composition were also similar.

  12. Comparison of Polysaccharides from Two Species of Ganoderma

    OpenAIRE

    Xie, Jing; Zhao, Jing; Hu, De-Jun; Duan, Jin-Ao; Tang, Yu-Ping; Li, Shao-Ping

    2012-01-01

    Ganoderma lucidum and Ganoderma sinense, known as Lingzhi in Chinese, are commonly used Chinese medicines with excellent beneficial health effects. Triterpenes and polysaccharides are usually considered as their main active components. However, the content of triterpenes differs significantly between the two species of Ganoderma. To date, a careful comparison of polysaccharides from the two species of Ganoderma has not been performed. In this study, polysaccharides from fruiting bodies of two...

  13. Optimized extraction of polysaccharides from Cymbopogon citratus and its biological activities.

    Science.gov (United States)

    Thangam, Ramar; Suresh, Veeraperumal; Kannan, Soundarapandian

    2014-04-01

    In this study the extraction of hot water soluble polysaccharides (HWSPs) from Cymbopogon citratus using hot water decoction was discussed. Response surface methodology (RSM) based on a three level, three variable central composite rotatable design (CCRD), was employed to obtain best possible combination of extraction time (X1: 30-180 min), extraction temperature (X2: 70-100 °C) and water to the raw material ratio (X3: 10-60) for maximum HWSPs extraction. The optimum extraction conditions were as follows: extraction time was around 113.81 min, extraction temperature at 99.66 °C and the ratio of water to raw material was 33.11 g/mL. Under these conditions, the experimental yield was 13.24±0.23%, which is well in close agreement with the value predicted by RSM model yield (13.19%). The basic characterization of HWSPs was determined by using the FTIR. These preliminary in vitro biological studies indicated that lemongrass polysaccharides were useful for anticancer therapy. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. [Gene deletion and functional analysis of the heptyl glycosyltransferase (waaF) gene in Vibrio parahemolyticus O-antigen cluster].

    Science.gov (United States)

    Zhao, Feng; Meng, Songsong; Zhou, Deqing

    2016-02-04

    To construct heptyl glycosyltransferase gene II (waaF) gene deletion mutant of Vibrio parahaemolyticus, and explore the function of the waaF gene in Vibrio parahaemolyticus. The waaF gene deletion mutant was constructed by chitin-based transformation technology using clinical isolates, and then the growth rate, morphology and serotypes were identified. The different sources (O3, O5 and O10) waaF gene complementations were constructed through E. coli S17λpir strains conjugative transferring with Vibrio parahaemolyticus, and the function of the waaF gene was further verified by serotypes. The waaF gene deletion mutant strain was successfully constructed and it grew normally. The growth rate and morphology of mutant were similar with the wild type strains (WT), but the mutant could not occurred agglutination reaction with O antisera. The O3 and O5 sources waaF gene complementations occurred agglutination reaction with O antisera, but the O10 sources waaF gene complementations was not. The waaF gene was related with O-antigen synthesis and it was the key gene of O-antigen synthesis pathway in Vibrio parahaemolyticus. The function of different sources waaF gene were not the same.

  15. Other age groups than children need to be considered as carriers of Streptococcal pneumoniae serotypes.

    Science.gov (United States)

    Slotved, Hans-Christian

    2016-10-02

    We need to raise the issue that focus on children as the only carriage group for pneumococci is not optimal; we need to consider that other age groups might also be carriers of pneumococcal serotypes causing invasive pneumococcal diseases (IPD) in unvaccinated age groups. The pneumococcal conjugate vaccines (PCV) have successfully removed IPD from vaccinated children. Studies have shown an effect of PCV reducing the pneumococcal carriage of PCV serotypes in children. The status for several countries having used PCV for many years is that they do not see PCV serotypes neither carried nor as a cause of IPD in children. PCV vaccination of children has shown a herd protection effect in unvaccinated groups as a reduction in IPD cases caused by PCV serotypes. However, not all PCV serotypes have disappeared as the cause of IPD in the unvaccinated age groups. The author therefore believes that if we are to see PCV serotypes disappear as a cause of IPD in unvaccinated age groups, we need to perform further carriage studies to examine carriage in other age groups. Alternatively, all age groups should be vaccinated against pneumococci to eliminate IPD caused by PCV serotypes from possible hidden carriers.

  16. Radiation-chemical destruction of cellulose and other polysaccharides

    International Nuclear Information System (INIS)

    Ershov, B.G.

    1998-01-01

    The studies concerning the radiation-chemical destruction of cellulose, its ethers and some polysaccharides (xylan, starch, decstrans, chitin, chitosan and geparin) are discussed. Ionising irradiation causes the destruction of these compounds with the decay of pyranose ring, accompanied by the formation of compounds containing carbonyl or carboxyl groups, as well as hydrogen, carbon dioxide, and carbon oxide. The efficiency of radiation degradation increases with increasing the temperature and depends on the structure of polysaccharides and the nature of substituents. The mechanism of radiation-chemical transformations of cellulose and others polysaccharides is proposed. Prospects of the application of radiation-chemical methods of treatment of cellulose and other polysaccharides in industry and agriculture considered [ru

  17. Improved coupling of bacterial polysaccharides to macromolecules and solid supports

    DEFF Research Database (Denmark)

    2013-01-01

    The invention relates to a method of producing a polysaccharide-carrier conjugate comprising coupling a polysaccharide to a carrier, said polysaccharide comprising at least one monosaccharide unit comprising a keto-carboxy group according to the formula -C(=O)COOR, where R is either hydrogen or C1......-alkoxyamine group of the carrier with a keto-carboxy group of said polysaccharide to form a covalent amide bond between the carrier and the polysaccharide. Another aspect of the present invention relates to a compound or solid surface obtained when performing the method of the present invention. A third aspect...

  18. Draft Genome Sequences of Actinobacillus pleuropneumoniae Serotypes 2 and 6

    DEFF Research Database (Denmark)

    Zhan, Bujie; Angen, Øystein; Hedegaard, Jakob

    2010-01-01

    Actinobacillus pleuropneumoniae is a bacterial pathogen that causes highly contagious respiratory infection in pigs and has a serious impact on the production economy and animal welfare. As clear differences in virulence between serotypes have been observed, the genetic basis should be investigat...... at the genomic level. Here, we present the draft genome sequences of the A. pleuropneumoniae serotypes 2 (strain 4226) and 6 (strain Femo)....

  19. Cepas invasivas de pneumococo isoladas de crianças e adolescentes em Salvador Invasive pneumococcal strains isolated from children and adolescents in Salvador

    Directory of Open Access Journals (Sweden)

    Cristiana M. Nascimento-Carvalho

    2003-06-01

    Full Text Available OBJETIVOS: descrever resistência antimicrobiana e sorotipos de cepas de pneumococo. MÉTODOS: durante 57 meses, foi conduzida uma vigilância de cepas invasivas de pneumococo de pacientes com idade OBJECTIVE: describe the antimicrobial resistance and serotype distribution of pneumococcal strains. METHODS: in a 57-month period, a laboratory-based surveillance of invasive pneumococcal strains from patients aged < 20 years was conducted. Pneumococcus was identified by means of tests for solubility in bile and optochin. Pneumococcal resistance to penicillin was screened by 1µg oxacillin disc and minimal inhibitory concentration was determined for the strains not susceptible to penicillin. Disc diffusion and broth microdilution methods were used for surveillance of resistance to other antimicrobials. Pneumococci were serotyped by means of the Neufeld-Quellung reactions. RESULTS: of 70 patients, 57.1% were males. The mean age was 1.92 yrs (mean 3.19 + 3.66 yrs, range 1 month to 19.5 yrs; 52.9% and 81.4% were < 2 yrs and < 5 yrs, respectively. The strains were isolated from blood (91.4%, CSF (2.9%, pleural (2.9%, peritoneal (1.4% and abscess (1.4% fluids from patients with pneumonia (77.1%, fever without localizing signs (10.0%, meningitis (4.3%, others (8.6%. Resistance was detected to penicillin (20.0%, trimethoprim-sulfamethoxazole (65.7%, tetracycline (21.4%, ofloxacin (6.3%, erythromycin (5.7%, clindamycin (2.9%. All tested strains were susceptible to chloramphenicol and vancomycin. Among penicillin-resistant strains, high resistance was detected in one, the same that showed intermediate resistance to cefotaxime. The most frequent serotypes were: 14 (22.9%, 5 and 6A (10.0% each, 6B and 19F (8.6% each, 9V, 18C and 23F (5.7% each. Resistance to penicillin was detected in serotypes 14 (71.4%, 6B and 19F (14.3% each. CONCLUSIONS: of 70 strains, 67.2% were classified as serotypes included in the heptavalent conjugate pneumococcal vaccine as well as

  20. Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited

    DEFF Research Database (Denmark)

    Martens, Pernille; Worm, Signe Westring; Lundgren, Bettina

    2004-01-01

    Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited.Martens P, Worm SW, Lundgren B, Konradsen HB, Benfield T. Department of Infectious Diseases 144, Hvidovre University Hospital, DK-2650 Hvidovre, Denmark. pernillemartens@yahoo.com BACKGROUND: Invasive infection...... with Streptococcus pneumoniae (pneumococci) causes significant morbidity and mortality. Case series and experimental data have shown that the capsular serotype is involved in the pathogenesis and a determinant of disease outcome. METHODS: Retrospective review of 464 cases of invasive disease among adults diagnosed...

  1. Identification of antigenic regions on VP2 of African horsesickness virus serotype 3 by using phage-displayed epitope libraries.

    Science.gov (United States)

    Bentley, L; Fehrsen, J; Jordaan, F; Huismans, H; du Plessis, D H

    2000-04-01

    VP2 is an outer capsid protein of African horsesickness virus (AHSV) and is recognized by serotype-discriminatory neutralizing antibodies. With the objective of locating its antigenic regions, a filamentous phage library was constructed that displayed peptides derived from the fragmentation of a cDNA copy of the gene encoding VP2. Peptides ranging in size from approximately 30 to 100 amino acids were fused with pIII, the attachment protein of the display vector, fUSE2. To ensure maximum diversity, the final library consisted of three sub-libraries. The first utilized enzymatically fragmented DNA encoding only the VP2 gene, the second included plasmid sequences, while the third included a PCR step designed to allow different peptide-encoding sequences to recombine before ligation into the vector. The resulting composite library was subjected to immunoaffinity selection with AHSV-specific polyclonal chicken IgY, polyclonal horse immunoglobulins and a monoclonal antibody (MAb) known to neutralize AHSV. Antigenic peptides were located by sequencing the DNA of phages bound by the antibodies. Most antigenic determinants capable of being mapped by this method were located in the N-terminal half of VP2. Important binding areas were mapped with high resolution by identifying the minimum overlapping areas of the selected peptides. The MAb was also used to screen a random 17-mer epitope library. Sequences that may be part of a discontinuous neutralization epitope were identified. The amino acid sequences of the antigenic regions on VP2 of serotype 3 were compared with corresponding regions on three other serotypes, revealing regions with the potential to discriminate AHSV serotypes serologically.

  2. Characterization of polysaccharides from Ganoderma spp. using saccharide mapping.

    Science.gov (United States)

    Wu, Ding-Tao; Xie, Jing; Hu, De-Jun; Zhao, Jing; Li, Shao-Ping

    2013-09-12

    Polysaccharides from Ganoderma spp. and their adulterants were firstly investigated and compared using saccharide mapping, enzymatic (endo-1,3-β-D-glucanase and pectinase) digestion followed by polysaccharide analysis using carbohydrate gel electrophoresis analysis. The results showed that both 1,3-β-D-glucosidic and 1,4-α-D-galactosiduronic linkages were existed in Lingzhi (Ganoderma lucidum and Ganoderma sinense), and the similarity of polysaccharides from G. lucidum and G. sinense was high, which may contribute to rational use of Lingzhi. Different species of Ganoderma and their adulterants can be differentiated based on the saccharide mapping, which is helpful to well understand the structural characters of polysaccharides from different species of Ganoderma and to improve the quality control of polysaccharides in Lingzhi. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Chemical characteristics and anti-proliferation activities of Ganoderma tsugae polysaccharides.

    Science.gov (United States)

    Chien, Rao-Chi; Yen, Ming-Tsung; Tseng, Yu-Hsiu; Mau, Jeng-Leun

    2015-09-05

    Polysaccharides were extracted by hot-water and hot-alkali from four forms of Ganoderma tsugae including mature and baby Ling chih, mycelium and filtrate. Different profiles of proximate composition and monosaccharide constituents, and element contents were found in the extracted polysaccharides from different extractions and different forms. The molecular weight distributions of polysaccharides were 2.8×10(4)-6.5×10(5)Da and their infrared spectra were comparable. The hot-alkali extracted polysaccharides exhibited better anti-proliferation on IMR32 cells than the hot-water extracted polysaccharides, which were in turn more effective than the hot-water extracts. Besides, most hot-water extracts and both extracted polysaccharides exhibited an anti-proliferation effect on Hep G2 cells. However, the hot-water extracts showed less effective in anti-proliferation of IMR32 and Hep G2 cells. Based on the anti-tumor effects, both polysaccharides could be prepared for use in the formulation of nutraceuticals and functional foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Complete and incomplete fusion dynamics in 19F + 154Sm system

    International Nuclear Information System (INIS)

    Singh, D.; Giri, Pankaj K.; Linda, Sneha B.

    2016-01-01

    Several experimental and theoretical studies based on spin distribution measurement have been carried out by using α-cluster structured projectile with different target nuclei but spin distribution measurement studies to localize the ℓ-window of CF and ICF by using non alpha cluster structured projectile scarcely exist in the literature. Therefore, to reach on some definite conclusion regarding the projectile structure and projectile energy effect on ICF dynamics especially by using non alpha cluster structured projectile, the spin distribution measurement of the evaporation residues produced through CF and ICF dynamics in the 19 F + 154 Sm system at projectile energies 110 and 100 MeV has been done

  5. Structure of polysaccharide antibiotics

    International Nuclear Information System (INIS)

    Matutano, L.

    1966-01-01

    Study of the structure of antibiotics having two or several sugars in their molecule. One may distinguish: the polysaccharide antibiotics themselves, made up of two or several sugars either with or without nitrogen, such as streptomycin, neomycins, paromomycine, kanamycin, chalcomycin; the hetero-polysaccharide antibiotics made up of one saccharide part linked to an aglycone of various type through a glucoside: macrolide, pigment, pyrimidine purine. Amongst these latter are: erythromycin, magnamycin, spiramycin, oleandomycin, cinerubin and amicetin. The sugars can either play a direct role in biochemical reactions or act as a dissolving agent, as far as the anti-microbe power of these antibiotics is concerned. (author) [fr

  6. Prevalence, antimicrobial susceptibility and multiplex PCR-serotyping of Listeria monocytogenes isolated from humans, foods and livestock in Iran.

    Science.gov (United States)

    Lotfollahi, Lida; Chaharbalesh, Ardalan; Ahangarzadeh Rezaee, Mohammad; Hasani, Alka

    2017-06-01

    Listeria monocytogenes is a foodborne pathogen causing listeriosis, which potentially affects all individuals, especially pregnant women and immunocompromised persons. The present study investigated the prevalence, antimicrobial susceptibility and serotypes distribution of the isolated L. monocytogenes from Iran. Twenty two (4.97%) of 442 human, food and livestock samples were found to be positive for L. monocytogenes. L. monocytogenes was identified in 8.8% of 125 human samples, 2.99% of 267 food and 6% of 50 livestock samples. The standard disk diffusion method and minimum inhibitory concentration (MIC) assay were used for antimicrobial susceptibility testing and multiplex PCR for serotyping. Among the 22 isolates tested, 6 (27.2%) displayed resistance to penicillin G, with all of the isolates and 2 (9%) of them showing intermediate susceptibility to clindamycin and rifampicin, respectively. According to the MIC assay, the rate of resistance to penicillin G was the same as that of disk diffusion method, but 16 (72.7%) of isolates showed intermediate susceptibility to clindamycin using E-test. In the multiplex PCR, 19 (86.4%) of isolates belonged to serotype 1/2c or 3c and the remaining 3 isolates were identified as (4b, 4d or 4e) and (1/2a or 3a), respectively. The occurrence of resistance to penicillin G, which can be used in the treatment of listeriosis, is very alarming and more prevalence of 1/2c serotype, in comparison to 3 other important ones (1/2a, 1/2b and 4b), in Iran has been reported for the first time. To the best of our knowledge, this is the first study showing the distribution of various serogroups of L. monocytogenes from human and livestock in Iran. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Prevalence and serotype distribution of Listeria monocytogenes isolated from foods in Montevideo-Uruguay

    Directory of Open Access Journals (Sweden)

    Valeria Braga

    Full Text Available ABSTRACT The aim of this work was to study the prevalence of Listeria monocytogenes in foods obtained in retail shops and food industries located in Montevideo-Uruguay, and to identify the serogroups of the obtained isolates. Three-thousand one-hundred and seventy-five food samples (frozen, deli meats, ready-to-eat and cheese were analyzed. The obtained isolates were serogrouped by multiplex PCR and serotyped by conventional procedure. Genetic comparisons were performed using pulsed-field gel electrophoresis on a sub-set of isolates belonging to the same serotype successively recovered from the same establishment. L. monocytogenes was isolated from 11.2% of samples. The highest prevalence was observed in frozen foods (38%, followed by cheese (10%. 1/2b and 4b were the most frequently identified serotypes. In six of 236 analyzed establishments we successively recovered L. monocytogenes isolates belonging to the same serotype. Most of them corresponded to serotype 1/2b. Pulsed-field gel electrophoresis profiles suggest that at least 33% of L. monocytogenes 1/2b isolates are genetically related and that may remain viable for prolonged periods. The observed prevalence of L. monocytogenes was lower than reported in neighboring countries. Our findings highlight the role that frozen foods may play in the spread of this pathogen, and the relevance of serotypes 1/2b and 4b.

  8. Polysaccharides from Traditional Chinese Medicines: Extraction, Purification, Modification, and Biological Activity.

    Science.gov (United States)

    Chen, Yun; Yao, Fangke; Ming, Ke; Wang, Deyun; Hu, Yuanliang; Liu, Jiaguo

    2016-12-13

    Traditional Chinese Medicine (TCM) has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development.

  9. Administration of polysaccharide from Panax notoginseng prolonged the survival of H22 tumor-bearing mice

    Directory of Open Access Journals (Sweden)

    Li HY

    2016-06-01

    Full Text Available Huaiyu Li,1,* Longlong Gu,1,2,* Yuanyuan Zhong,1 Yajuan Chen,1 Lei Zhang,1 Annie R Zhang,3 Robert W Sobol,4,5 Tong Chen,1,6 Jianfeng Li4,5 1Yunnan Key Laboratory of Pharmacology for Natural Products, School of Pharmaceutical Sciences, 2Haiyuan College, Kunming Medical University, Kunming, Yunnan, People’s Republic of China; 3Graduate School of Applied and Professional Psychology, Rutgers, The State University of New Jersey, Piscataway, NJ, 4Department of Oncologic Sciences, 5Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA; 6Yunnan Panax notoginseng (Burk F.H. Chen Biotechnology and Pharmaceutical Engineering Research Center, Kunming, Yunnan, People’s Republic of China *These authors contributed equally to this work Background: Polysaccharides from various sources are being considered potential sources for the treatment of liver cancer. The aim of this study was to investigate the impact of polysaccharide isolated from Panax notoginseng (PPN on the proliferation of H22 liver cancer cells and the survival of the tumor-bearing mice transplanted with H22 cells.Materials and methods: Polysaccharide from PPN was added to the culture medium of mouse hepatoma H22 cells at different doses. Cell proliferation was assayed with a standard MTT assay. Survival rates of tumor-bearing mice were recorded. Peripheral blood lymphocytes were assayed by flow cytometry. Serum interleukin-2 levels in peripheral blood were measured by enzyme-linked immunosorbent assay.Results: Polysaccharide from PPN inhibited the growth of H22 cells and significantly prolonged the survival of tumor-bearing mice. The increase in activated CD4+ T-cells and the elevation of serum interleukin-2 may contribute to the antitumor activity of PPN.Conclusion: PPN has potential antitumor activity for the treatment of liver cancer. Keywords: polysaccharide, Panax notoginseng, liver cancer, immunotherapy, IL-2

  10. Crosslinked ionic polysaccharides for stimuli-sensitive drug delivery.

    Science.gov (United States)

    Alvarez-Lorenzo, Carmen; Blanco-Fernandez, Barbara; Puga, Ana M; Concheiro, Angel

    2013-08-01

    Polysaccharides are gaining increasing attention as components of stimuli-responsive drug delivery systems, particularly since they can be obtained in a well characterized and reproducible way from the natural sources. Ionic polysaccharides can be readily crosslinked to render hydrogel networks sensitive to a variety of internal and external variables, and thus suitable for switching drug release on-off through diverse mechanisms. Hybrids, composites and grafted polymers can reinforce the responsiveness and widen the range of stimuli to which polysaccharide-based systems can respond. This review analyzes the state of the art of crosslinked ionic polysaccharides as components of delivery systems that can regulate drug release as a function of changes in pH, ion nature and concentration, electric and magnetic field intensity, light wavelength, temperature, redox potential, and certain molecules (enzymes, illness markers, and so on). Examples of specific applications are provided. The information compiled demonstrates that crosslinked networks of ionic polysaccharides are suitable building blocks for developing advanced externally activated and feed-back modulated drug delivery systems. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Pasteurella multocida isolated from wild birds of North America: a serotype and DNA fingerprint study of isolates from 1978 to 1993

    Science.gov (United States)

    Wilson, M.A.; Duncan, R.M.; Nordholm, G.E.; Berlowski, B.M.

    1995-01-01

    Serotype and DNA fingerprint methods were used to study Pasteurella multocida isolated from 320 wild birds of North America. Isolates were collected during 1978-93. The HhaI profiles of 314 isolates matched the HhaI profile of somatic reference type 1, strain X-73; somatic type 1 antigen was expressed by 310 isolates, and the serotype of four isolates was undetected. Differentiation of the 314 isolates was observed by digestion of DNA with HpaII. None of the HpaII profiles matched the HpaII profile of X-73 (designated HhaI 001/HpaII 001). Three HpaII profiles were recognized among the somatic type 1 isolates: HpaII 002 (n = 18), HpaII 003 (n = 122), and HpaII 004 (n = 174). Profile HpaII 002 was found among isolates collected during 1979-83. Profile HpaII 003 was identified from isolates collected during 1979-89, with the exception of two isolates in 1992. The HpaII 004 profile was identified from isolates collected during 1983-93. Of the six remaining isolates, four expressed somatic type 4 and had HhaI profiles identical to the somatic type 4 reference strain P-1662 profile (designated HhaI 004); these isolates were differentiated by digestion of DNA with HpaII. One isolate was identified as serotype F:11, and another was serotype A:3,4. In the present study, 314 of 316 (99.4%) isolates from wild birds in the Central, Mississippi, and Pacific flyways during 1978-93, were P. multocida somatic type 1.

  12. Anticoagulant activity of a sulfated polysaccharide isolated from the green seaweed Caulerpa cupressoides

    Directory of Open Access Journals (Sweden)

    José Ariévilo Gurgel Rodrigues

    2011-08-01

    Full Text Available The aim of this study was to evaluate certain molecular characteristics of a sulfated polysaccharide (SPs with anticoagulant properties, isolated from Caulerpa cupressoides (Chlorophyta. Crude SPs were extracted by proteolytic digestion (papain, followed by ion-exchange chromatography on a DEAE-cellulose column. The fractions obtained were analyzed for molecular mass, 0.5% agarose gel electrophoresis and chemical composition. The activated partial thromboplastin time (APTT test was applied using normal human plasma and standard heparin (HEP (193 IU mg-1. The yield was ~ 3%, and the chromatography procedure separated the material into three different SP fractions (F I, F II and F III, eluted at the concentrations of 0.50, 0.75 and 1.00 M of NaCl, respectively. Only fraction F II was active (24.62 IU mg-1, with high sulfate content (23.79% and number of molecular mass peaks. Therefore, the APTT of a fraction isolated from C. cupressoides was less potent than HEP.

  13. [Effects of tree species on polysaccharides content of epiphytic Dendrobium officinale].

    Science.gov (United States)

    Guo, Ying-Ying; Zhu, Yan; Si, Jin-Ping; Liu, Jing-Jing; Wu, Cheng-Yong; Li, Hui

    2014-11-01

    To reveals the effects of tree species on polysaccharides content of epiphytic Dendrobium officinale. The polysaccharides content of D. officinale attached to living tress in wild or stumps in bionic-facility was determined by phenol-sulfuric acid method. There were extremely significant differences of polysaccharides content of D. officinale attached to different tree species, but the differences had no relationship with the form and nutrition of barks. The polysaccharides content of D. officinale mainly affected by the light intensity of environment, so reasonable illumination favored the accumulation of polysaccharides. Various polysaccharides content of D. officinal from different attached trees is due to the difference of light regulation, but not the form and nutrition of barks.

  14. Application of polymerase chain reaction to differentiate herpes simplex virus 1 and 2 serotypes in culture negative intraocular aspirates

    Directory of Open Access Journals (Sweden)

    Shyamal G

    2005-01-01

    Full Text Available Purpose: To standardize and apply a polymerase chain reaction (PCR on the glycoprotein D gene to differentiate Herpes simplex virus (HSV 1 & 2 serotypes in culture negative intraocular specimens. Methods: Twenty-one intraocular fluids collected from 19 patients were subjected to cultures for HSV and uniplex PCR (uPCR for DNA polymerase gene. To differentiate HSV serotypes, as 1 & 2, a seminested PCR (snPCR targeting the glycoprotein D gene was standardised and applied onto 21 intraocular fluids. The specificity of the snPCR was verified by application onto ATCC strains of HSV 1 and 2, clinical isolates and DNA sequencing of the amplified products. All specimens were also tested for the presence of cytomegalovirus (CMV and varicella zoster virus (VZV by nucleic acid amplification methods. Results: Four of the 21 intraocular fluids were positive for HSV by uPCR. snPCR detected HSV in three additional specimens (total of seven specimens, and identified three as HSV 1 and four as HSV 2. DNA sequencing of PCR products showed 100% homology with the standard strains of HSV 1 and 2 respectively. None of the samples were positive in culture. Among the other patients, CMV DNA was detected in two and VZV DNA in five others. Conclusions: The standardized snPCR can be applied directly onto the culture negative specimens for rapid differentiation of HSV serotypes.

  15. Design and construction of a novel 1H/19F double-tuned coil system using PIN-diode switches at 9.4T.

    Science.gov (United States)

    Choi, Chang-Hoon; Hong, Suk-Min; Ha, YongHyun; Shah, N Jon

    2017-06-01

    A double-tuned 1 H/ 19 F coil using PIN-diode switches was developed and its performance evaluated. The is a key difference from the previous developments being that this design used a PIN-diode switch in series with an additionally inserted inductor in parallel to one of the capacitors on the loop. The probe was adjusted to 19 F when the reverse bias voltage was applied (PIN-diode OFF), whilst it was switched to 1 H when forward current was flowing (PIN-diode ON). S-parameters and Q-factors of single- and double-tuned coils were examined and compared with/without a phantom on the bench. Imaging experiments were carried out on a 9.4T preclinical scanner. All coils were tuned at resonance frequencies and matched well. It is shown that the Q-ratio and SNR of double-tuned coil at 19 F frequency are nearly as good as those of a single-tuned coil. Since the operating frequency was tuned to 19 F when the PIN-diodes were turned off, losses due to PIN-diodes were substantially lower resulting in the provision of excellent image quality of X-nuclei. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Polysaccharides from Traditional Chinese Medicines: Extraction, Purification, Modification, and Biological Activity

    Directory of Open Access Journals (Sweden)

    Yun Chen

    2016-12-01

    Full Text Available Traditional Chinese Medicine (TCM has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development.

  17. Chromatography in characterization of polysaccharides from medicinal plants and fungi.

    Science.gov (United States)

    Hu, De-jun; Cheong, Kit-leong; Zhao, Jing; Li, Shao-ping

    2013-01-01

    Polysaccharides isolated from medicinal plants and fungi exhibit multiple pharmacological activities. The biological activities of polysaccharides depend on their chemical characteristics. However, characterization of polysaccahrides is a challenge because of their complicated structure and macromolecular mass. In this review, chromatography in characterization of polysaccharides, including physicochemical characterization (purity, molecular mass, and distribution), structural characterization (constituent monosaccharide composition and the ratio, the features of glycosidic linkages), and fingerprint of polysaccharides (acidic and enzymatic hydrolysates), from medicinal plants and fungi were reviewed and discussed according to the publications collected in Web of Science since 2007. The perspective for characterization of polysaccharides has also been described. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Lytic polysaccharide monooxygenases from Myceliophthora thermophila C1

    NARCIS (Netherlands)

    Frommhagen, Matthias

    2017-01-01

    Current developments aim at the effective enzymatic degradation of plant biomass polysaccharides into fermentable monosaccharides for biofuels and biochemicals. Recently discovered lytic polysaccharide monooxgygenases (LPMOs) boost the hydrolytic breakdown of lignocellulosic biomass, especially

  19. Direct visualization of in vitro drug mobilization from Lescol XL tablets using two-dimensional (19)F and (1)H magnetic resonance imaging.

    Science.gov (United States)

    Chen, Chen; Gladden, Lynn F; Mantle, Michael D

    2014-02-03

    This article reports the application of in vitro multinuclear ((19)F and (1)H) two-dimensional magnetic resonance imaging (MRI) to study both dissolution media ingress and drug egress from a commercial Lescol XL extended release tablet in a United States Pharmacopeia Type IV (USP-IV) dissolution cell under pharmacopoeial conditions. Noninvasive spatial maps of tablet swelling and dissolution, as well as the mobilization and distribution of the drug are quantified and visualized. Two-dimensional active pharmaceutical ingredient (API) mobilization and distribution maps were obtained via (19)F MRI. (19)F API maps were coregistered with (1)H T2-relaxation time maps enabling the simultaneous visualization of drug distribution and gel layer dynamics within the swollen tablet. The behavior of the MRI data is also discussed in terms of its relationship to the UV drug release behavior.

  20. Structural Characterization and Enzymatic Modification of Soybean Polysaccharides

    DEFF Research Database (Denmark)

    Pierce, Brian; Wichmann, Jesper

    % galacturonic acid, 8% xylose, 3% rhamnose, and 3% fucose. Currently, the majority of this material is disposed of as waste, increasing production costs. Opportunities exist for the develop-ment of novel functional ingredients from this abundant and underutilized ma-terial; however, efforts in this area......The work in this thesis explores the structure of soybean polysaccharides, and examines approaches for the chemical and enzymatic degradation and solu-bilization of this material. Soybean polysaccharides are produced in large quantities globally as a by-product of various soy production processes...... are currently limited by the material’s insol-ubility. A central hypothesis of this work was that by obtaining a more complete understanding of the structure of this material, chemical and enzymatic ap-proaches could be developed to modify the polysaccharides, creating soluble polysaccharide fractions...

  1. E2F1 induces p19INK4d, a protein involved in the DNA damage response, following UV irradiation.

    Science.gov (United States)

    Carcagno, Abel L; Giono, Luciana E; Marazita, Mariela C; Castillo, Daniela S; Pregi, Nicolás; Cánepa, Eduardo T

    2012-07-01

    Central to the maintenance of genomic integrity is the cellular DNA damage response. Depending on the type of genotoxic stress and through the activation of multiple signaling cascades, it can lead to cell cycle arrest, DNA repair, senescence, and apoptosis. p19INK4d, a member of the INK4 family of CDK inhibitors, plays a dual role in the DNA damage response, inhibiting cell proliferation and promoting DNA repair. Consistently, p19INK4d has been reported to become upregulated in response to UV irradiation and a great variety of genotoxic agents. Here, this induction is shown to result from a transcriptional stimulatory mechanism that can occur at every phase of the cell cycle except during mitosis. Moreover, evidence is presented that demonstrates that E2F1 is involved in the induction of p19INK4d following UV treatment, as it is prevented by E2F1 protein ablation and DNA-binding inhibition. Specific inhibition of this regulation using triplex-forming oligonucleotides that target the E2F response elements present in the p19INK4d promoter also block p19INK4d upregulation and sensitize cells to DNA damage. These results constitute the first description of a mechanism for the induction of p19INK4d in response to UV irradiation and demonstrate the physiological relevance of this regulation following DNA damage.

  2. A novel plasmid-encoded serotype conversion mechanism through addition of phosphoethanolamine to the O-antigen of Shigella flexneri.

    Directory of Open Access Journals (Sweden)

    Qiangzheng Sun

    Full Text Available Shigella flexneri is the major pathogen causing bacillary dysentery in developing countries. S. flexneri is divided into at least 16 serotypes based on the combination of antigenic determinants present in the O-antigen. All the serotypes (except for serotype 6 share a basic O-unit containing one N-acetyl-d-glucosamine and three l-rhamnose residues, whereas differences between the serotypes are conferred by phage-encoded glucosylation and/or O-acetylation. Serotype Xv is a newly emerged and the most prevalent serotype in China, which can agglutinate with both MASF IV-1 and 7,8 monoclonal antibodies. The factor responsible for the presence of MASF IV-1 (E1037 epitope has not yet been identified. In this study, we analyzed the LPS structure of serotype Xv strains and found that the MASF IV-1 positive phenotype depends on an O-antigen modification with a phosphoethanolamine (PEtN group attached at position 3 of one of the rhamnose residues. A plasmid carried gene, lpt-O (LPS phosphoethanolamine transferase for O-antigen, mediates the addition of PEtN for serotype Xv and other MASF IV-1 positive strains. These findings reveal a novel serotype conversion mechanism in S. flexneri and show the necessity of further extension of the serotype classification scheme recognizing the MASF IV-1 positive strains as distinctive subtypes.

  3. Characterization and antioxidant activities of polysaccharides from thirteen boletus mushrooms.

    Science.gov (United States)

    Zhang, Lan; Hu, Yu; Duan, Xiaoyu; Tang, Tingting; Shen, Yingbin; Hu, Bin; Liu, Aiping; Chen, Hong; Li, Cheng; Liu, Yuntao

    2018-07-01

    Water-soluble polysaccharides were extracted from the caps and stipes of thirteen boletus mushrooms representing five different species collected in Southwest China. Investigations of their structures and antioxidant activities allowed an evaluation of structure-function relationships. The polysaccharides were composed mainly of the monosaccharides arabinose, xylose, mannose, glucose and galactose. Most samples displayed a broad molecular weight range, with significant differences observed between the molecular weight ranges of the polysaccharides from the caps and the stipes. FT-IR spectral analysis of the polysaccharides revealed that most of polysaccharides from boletus mushrooms (except Boletus edulis) contained a pyranose ring. The antioxidant activities of the polysaccharides in stipes showed a significant correlation with their monosaccharide composition, and were also related to their molecular weight and anomeric configuration. Suillellus luridus collected in Pingwu, Mianyang, Sichuan, China had remarkably superior antioxidant activity and might be developed as a natural antioxidant. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Thermonuclear 19F(p, {{\\boldsymbol{\\alpha }}}_{0})16O reaction rate

    Science.gov (United States)

    He, Jian-Jun; Lombardo, Ivano; Dell'Aquila, Daniele; Xu, Yi; Zhang, Li-Yong; Liu, Wei-Ping

    2018-01-01

    The thermonuclear 19F(p, {{{α }}}0)16O reaction rate in the temperature region 0.007-10 GK has been derived by re-evaluating the available experimental data, together with the low-energy theoretical R-matrix extrapolations. Our new rate deviates by up to about 30% compared to the previous results, although all rates are consistent within the uncertainties. At very low temperature (e.g. 0.01 GK) our reaction rate is about 20% lower than the most recently published rate, because of a difference in the low energy extrapolated S-factor and a more accurate estimate of the reduced mass used in the calculation of the reaction rate. At temperatures above ˜1 GK, our rate is lower, for instance, by about 20% around 1.75 GK, because we have re-evaluated the previous data (Isoya et al., Nucl. Phys. 7, 116 (1958)) in a meticulous way. The present interpretation is supported by the direct experimental data. The uncertainties of the present evaluated rate are estimated to be about 20% in the temperature region below 0.2 GK, and are mainly caused by the lack of low-energy experimental data and the large uncertainties in the existing data. Asymptotic giant branch (AGB) stars evolve at temperatures below 0.2 GK, where the 19F(p, {{α }})16O reaction may play a very important role. However, the current accuracy of the reaction rate is insufficient to help to describe, in a careful way, the fluorine over-abundances observed in AGB stars. Precise cross section (or S factor) data in the low energy region are therefore needed for astrophysical nucleosynthesis studies. Supported by National Natural Science Foundation of China (11490562, 11490560, 11675229) and National Key Research and Development Program of China (2016YFA0400503)

  5. Studies on water soluble polysaccharides from Pithecellobium dulce (Roxb.) Benth. seeds.

    Science.gov (United States)

    Bagchi, S; Kumar, K Jayaram

    2016-03-15

    In this existing experimental work, water soluble PDP polysaccharides were secluded from Pithecellobium dulce (Roxb.) Benth. seeds. The physicochemical properties were analyzed in terms of swelling power, solubility, pH and water holding capacity. Micromeretic studies proved the polysaccharide may be used a potential pharmaceutical adjuvant. The polysaccharide was characterized by FT-IR, SEM, TGA and NMR techniques. Methylation analysis confirmed that the polysaccharide is composed of Arabinose (Araf) units. The chemical shifts of anomeric proton region were found in the region of 4.4-5.5ppm. Thermogravimetric analysis showed that PDP polysaccharide was thermally stable. The in vitro antioxidant capacities of the polysaccharide were investigated in terms of scavenging of hydroxyl radicals, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radicals, hydrogen peroxide (H2O2) and reducing power assay. The polysaccharide fractions showed activity in a concentration dependent manner which was comparable to the standard, ascorbic acid. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Non-cellulosic polysaccharides from cotton fibre are differently impacted by textile processing

    DEFF Research Database (Denmark)

    Runavot, Jean-Luc; Guo, Xiaoyuan; Willats, William George Tycho

    2014-01-01

    -cellulosic cotton fibre polysaccharides during different steps of cotton textile processing using GC-MS, HPLC and comprehensive microarray polymer profiling to obtain monosaccharide and polysaccharide amounts and linkage compositions. Additionally, in situ detection was used to obtain information on polysaccharide......Cotton fibre is mainly composed of cellulose, although non-cellulosic polysaccharides play key roles during fibre development and are still present in the harvested fibre. This study aimed at determining the fate of non-cellulosic polysaccharides during cotton textile processing. We analyzed non...... localization and accessibility. We show that pectic and hemicellulosic polysaccharide levels decrease during cotton textile processing and that some processing steps have more impact than others. Pectins and arabinose-containing polysaccharides are strongly impacted by the chemical treatments, with most being...

  7. Polysaccharides isolated from Açaí fruit induce innate immune responses.

    Directory of Open Access Journals (Sweden)

    Jeff Holderness

    2011-02-01

    Full Text Available The Açaí (Acai fruit is a popular nutritional supplement that purportedly enhances immune system function. These anecdotal claims are supported by limited studies describing immune responses to the Acai polyphenol fraction. Previously, we characterized γδ T cell responses to both polyphenol and polysaccharide fractions from several plant-derived nutritional supplements. Similar polyphenol and polysaccharide fractions are found in Acai fruit. Thus, we hypothesized that one or both of these fractions could activate γδ T cells. Contrary to previous reports, we did not identify agonist activity in the polyphenol fraction; however, the Acai polysaccharide fraction induced robust γδ T cell stimulatory activity in human, mouse, and bovine PBMC cultures. To characterize the immune response to Acai polysaccharides, we fractionated the crude polysaccharide preparation and tested these fractions for activity in human PBMC cultures. The largest Acai polysaccharides were the most active in vitro as indicated by activation of myeloid and γδ T cells. When delivered in vivo, Acai polysaccharide induced myeloid cell recruitment and IL-12 production. These results define innate immune responses induced by the polysaccharide component of Acai and have implications for the treatment of asthma and infectious disease.

  8. Mapping the polysaccharide degradation potential of Aspergillus niger

    Science.gov (United States)

    2012-01-01

    Background The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For each type of hemicellulose, a complex mixture of enzymes is required for complete conversion to fermentable monosaccharides. In plant-biomass degrading fungi, these enzymes are regulated and released by complex regulatory structures. In this study, we present a methodology for evaluating the potential of a given fungus for polysaccharide degradation. Results Through the compilation of information from 203 articles, we have systematized knowledge on the structure and degradation of 16 major types of plant polysaccharides to form a graphical overview. As a case example, we have combined this with a list of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono- and polysaccharide substrates has allowed elucidation of concerted gene expression from this organism. One such example is the identification of a full set of extracellular polysaccharide-acting genes for the degradation of oat spelt xylan. Conclusions The mapping of plant polysaccharide structures along with the corresponding enzymatic activities is a powerful framework for expression analysis of carbohydrate-active enzymes. Applying this network-based approach, we provide the first genome-scale characterization of all genes coding for carbohydrate-active enzymes identified in A. niger. PMID:22799883

  9. escherichia coli serotypes confirmed in experimental mammary ...

    African Journals Online (AJOL)

    DJFLEX

    VARIATIONS IN VIRULENCE OF THREE (3) ESCHERICHIA COLI. SEROTYPES CONFIRMED IN ... ows are susceptible to E. coli infection because. E. coli exist in the .... Coli infections in mice: A laboratory animal model for research in.

  10. Excitation functions of pion reactions on 14N, 16O, and 19F through the (3,3) resonance

    International Nuclear Information System (INIS)

    Jacob, N.P. Jr.; Markowitz, S.S.

    1976-01-01

    Cross sections for pion-induced reactions of the form (π,πN) and more complex spallation reactions of the form (π,X) have been measured from 50--550 MeV on the target nuclei 14 N, 16 O, and 19 F using the secondary pion beams at the Lawrence Berkeley Laboratory 184-inch synchrocyclotron and the Clinton P. Anderson Meson Physics Facility. The dominance of the (3,3) free-particle resonance is seen in all excitation functions determined in this work. Relative to the 12 C(π/sup plus-or-minus/,πN) 11 C reactions, the (π/sup plus-or-minus/,πN) reactions on 14 N, 16 O, and 19 F have magnitudes of 0.2, 1, and 0.7, respectively. The cross section ratio R=sigma (π - ,π - n)/sigma (π + ,π N) =1.68+-0.18 for 14 N at 188+-15 MeV, 1.68+-0.05 for 16 O at 188+-9 MeV, and 1.68+-0.03 for 19 F at 178+-2 MeV incident pion energy. The results from this work are compared to previous pion work, analogous proton-induced reactions, Monte Carlo intranuclear cascade-evaporation calculations, and to a semiclassical nucleon charge-exchange model which convincingly explains the (π,πN) reaction mechanism in the (3,3) resonance region

  11. Trypsin diminishes the rat potency of polio serotype 3.

    Science.gov (United States)

    ten Have, R; Westdijk, J; Levels, L M A R; Koedam, P; de Haan, A; Hamzink, M R J; Metz, B; Kersten, G F A

    2015-11-01

    This study addresses observations made in view of testing in practice the guideline in the European Pharmacopoeia (EP) on omitting the rat potency test for release of polio containing vaccines. In general, use of the guideline is valid and the D-antigen ELISA can indeed be used as an in vitro alternative for the in vivo test. However, the set-up of the ELISA is crucial and should include detection of antigenic site 1 in polio serotype 3 as destruction of that site by trypsin results in a reduced rat potency. Antigenic site 1 in polio serotype 2 may also be modified by trypsin, but the cleavage of viral protein 1 (VP1) did not affect the rat potency. Therefore, any antigenic site, except site 1, can be used for detection of polio serotype 2. It is advised to include testing of the effect of trypsin treatment in the EP-guideline. This allows polio vaccine manufacturers to check whether their in-house ELISA needs improvement. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  12. Bacillus subtilis biofilm induction by plant polysaccharides.

    Science.gov (United States)

    Beauregard, Pascale B; Chai, Yunrong; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2013-04-23

    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.

  13. Vibrio parahaemolyticus Strains of Pandemic Serotypes Identified from Clinical and Environmental Samples from Jiangsu, China

    Directory of Open Access Journals (Sweden)

    Jingjiao eLi

    2016-05-01

    Full Text Available Vibrio parahaemolyticus has emerged as a major foodborne pathogen in China, Japan, Thailand and other Asian countries. In this study, 72 strains of V. parahaemolyticus were isolated from clinical and environmental samples between 2006 and 2014 in Jiangsu, China. The serotypes and six virulence genes including thermostable direct hemolysin (TDR and TDR-related hemolysin (TRH genes were assessed among the isolates. Twenty five serotypes were identified and O3:K6 was one of the dominant serotypes. The genetic diversity was assessed by multilocus sequence typing (MLST analysis, and 48 sequence types (STs were found, suggesting this V. parahaemolyticus group is widely dispersed and undergoing rapid evolution. A total of 25 strains of pandemic serotypes such as O3:K6, O5:K17 and O1:KUT were identified. It is worth noting that the pandemic serotypes were not exclusively identified from clinical samples, rather, nine strains were also isolated from environmental samples; and some of these strains harbored several virulence genes, which may render those strains pathogenicity potential. Therefore, the emergence of these environmental pandemic V. parahaemolyticus strains may poses a new threat to the public health in China. Furthermore, six novel serotypes and 34 novel STs were identified among the 72 isolates, indicating that V. parahaemolyticus were widely distributed and fast evolving in the environment in Jiangsu, China. The findings of this study provide new insight into the phylogenic relationship between V. parahaemolyticus strains of pandemic serotypes from clinical and environmental sources and enhance the MLST database; and our proposed possible O- and K- antigen evolving paths of V. parahaemolyticus may help understand how the serotypes of this dispersed bacterial population evolve.

  14. Extraction, purification and antioxidant activities of the polysaccharides from maca (Lepidium meyenii).

    Science.gov (United States)

    Zha, Shenghua; Zhao, Qingsheng; Chen, Jinjin; Wang, Liwei; Zhang, Guifeng; Zhang, Hong; Zhao, Bing

    2014-10-13

    Water-soluble polysaccharides were separated from maca (Lepidium meyenii) aqueous extract (MAE). The crude polysaccharides were deproteinized by Sevag method. During the preparation process of maca polysaccharides, amylase and glucoamylase effectively removed starch in maca polysaccharides. Four Lepidium meyenii polysaccharides (LMPs) were obtained by changing the concentration of ethanol in the process of polysaccharide precipitation. All of the LMPs were composed of rhamnose, arabinose, glucose and galactose. Antioxidant activity tests revealed that LMP-60 showed good capability of scavenging hydroxyl free radical and superoxide radical at 2.0mg/mL, the scavenging rate was 52.9% and 85.8%, respectively. Therefore, the results showed that maca polysaccharides had a high antioxidant activity and could be explored as the source of bioactive compounds. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Java project on periodontal diseases : serotype distribution of Aggregatibacter actinomycetemcomitans and serotype dynamics over an 8-year period

    NARCIS (Netherlands)

    van der Reijden, Wil A.; Bosch-Tijhof, Carolien J.; van der Velden, Ubele; van Winkelhoff, Arie Jan

    Objective: To investigate the serotype distribution and stability of Aggregatibacter actinomycetemcomitans over an 8-year period in untreated Indonesian subjects. Material and Methods: Clinical periodontal status and the presence of A. actinomycetemcomitans were established in 1994 and 2002 in 107

  16. Static and dynamic {sup 18}F-FET PET for the characterization of gliomas defined by IDH and 1p/19q status

    Energy Technology Data Exchange (ETDEWEB)

    Verger, Antoine [Forschungszentrum Juelich, Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5), Juelich (Germany); Lorraine University, Department of Nuclear Medicine and Nancyclotep Imaging Platform, CHRU Nancy, Nancy (France); Lorraine University, IADI, INSERM, UMR 947, Nancy (France); Service de Medecine Nucleaire, Vandoeuvre-les-Nancy (France); Stoffels, Gabriele; Lohmann, Philipp; Neumaier, Bernd [Forschungszentrum Juelich, Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5), Juelich (Germany); Bauer, Elena K. [University Hospital Cologne, Department of Neurology, Cologne (Germany); Blau, Tobias [University Hospital Cologne, Department of Neuropathology, Cologne (Germany); Fink, Gereon R. [Forschungszentrum Juelich, Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5), Juelich (Germany); University Hospital Cologne, Department of Neurology, Cologne (Germany); Shah, Nadim J. [Forschungszentrum Juelich, Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5), Juelich (Germany); RWTH Aachen University Hospital, Department of Neurology, Aachen (Germany); Section JARA-Brain, Juelich-Aachen Research Alliance (JARA), Juelich (Germany); Langen, Karl-Josef [Forschungszentrum Juelich, Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5), Juelich (Germany); Section JARA-Brain, Juelich-Aachen Research Alliance (JARA), Juelich (Germany); RWTH Aachen University Hospital, Department of Nuclear Medicine, Aachen (Germany); Galldiks, Norbert [Forschungszentrum Juelich, Institute of Neuroscience and Medicine (INM-3, INM-4, INM-5), Juelich (Germany); University Hospital Cologne, Department of Neurology, Cologne (Germany); Universities of Cologne and Bonn, Center of Integrated Oncology (CIO), Cologne (Germany)

    2018-03-15

    The molecular features isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion have gained major importance for both glioma typing and prognosis and have, therefore, been integrated in the World Health Organization (WHO) classification in 2016. The aim of this study was to characterize static and dynamic O-(2-{sup 18}F-fluoroethyl)-L-tyrosine ({sup 18}F-FET) PET parameters in gliomas with or without IDH mutation or 1p/19q co-deletion. Ninety patients with newly diagnosed and untreated gliomas with a static and dynamic {sup 18}F-FET PET scan prior to evaluation of tumor tissue according to the 2016 WHO classification were identified retrospectively. Mean and maximum tumor-to-brain ratios (TBR{sub mean/max}), as well as dynamic parameters (time-to-peak and slope) of {sup 18}F-FET uptake were calculated. Sixteen (18%) oligodendrogliomas (IDH mutated, 1p/19q co-deleted), 27 (30%) astrocytomas (IDH mutated only), and 47 (52%) glioblastomas (IDH wild type only) were identified. TBR{sub mean}, TBR{sub max}, TTP and slope discriminated between IDH mutated astrocytomas and IDH wild type glioblastomas (P < 0.01). TBR{sub mean} showed the best diagnostic performance (cut-off 1.95; sensitivity, 89%; specificity, 67%; accuracy, 81%). None of the parameters discriminated between oligodendrogliomas (IDH mutated, 1p/19q co-deleted) and glioblastomas or astrocytomas. Furthermore, TBR{sub mean}, TBR{sub max}, TTP, and slope discriminated between gliomas with and without IDH mutation (p < 0.01). The best diagnostic performance was obtained for the combination of TTP with TBR{sub max} or slope (accuracy, 73%). Data suggest that static and dynamic {sup 18}F-FET PET parameters may allow determining non-invasively the IDH mutation status. However, IDH mutated and 1p/19q co-deleted oligodendrogliomas cannot be differentiated from glioblastomas and astrocytomas by {sup 18}F-FET PET. (orig.)

  17. Detection of Inulin, a Prebiotic Polysaccharide, in Maple Syrup.

    Science.gov (United States)

    Sun, Jiadong; Ma, Hang; Seeram, Navindra P; Rowley, David C

    2016-09-28

    Maple syrup is a widely consumed plant-derived natural sweetener produced by concentrating xylem sap collected from certain maple (Acer) species. During thermal evaporation of water, natural phytochemical components are concentrated in maple syrup. The polymeric components from maple syrup were isolated by ethanol precipitation, dialysis, and anion exchange chromatography and structurally characterized by glycosyl composition analysis, glycosyl linkage analysis, and nuclear magnetic resonance spectroscopy. Among the maple syrup polysaccharides, one neutral polysaccharide was characterized as inulin with a broad molecular weight distribution, representing the first isolation of this prebiotic carbohydrate from a xylem sap. In addition, two acidic polysaccharides with structural similarity were identified as arabinogalactans derived from rhamnogalacturonan type I pectic polysaccharides.

  18. Life cycle assessment of polysaccharide materials: a review

    NARCIS (Netherlands)

    Shen, L.|info:eu-repo/dai/nl/310872022; Patel, M.K.|info:eu-repo/dai/nl/18988097X

    2008-01-01

    Apart from conventional uses of polysaccharide materials, such as food, clothing, paper packaging and construction, new polysaccharide products and materials have been developed. This paper reviews life cycle assessment (LCA) studies in order to gain insight of the environmental profiles of

  19. Magnetic vacancies; simulations and TDPAD experiments with 19 F in Al(x) Fe(1-x)

    International Nuclear Information System (INIS)

    Ekwall, B.; Johansson, K.; Lidbjoerk, P.; Lindgren, B.; Norlin, L.O.

    1984-04-01

    Al(x) Fe(1-x) alloys with less or equal 4.2 at percent have been studied by the TDPAD method utilising 19 F as probe. The hyperfine field was found to increase with 0.39(6) percent per at percent Al. A Monte Carlo simulation of the dipolar distribution, due to the missing Fe moments, agrees well with the experimental results.(author)

  20. Glycosylation intermediates studied using low temperature 1H- and 19F-DOSY NMR

    DEFF Research Database (Denmark)

    Qiao, Yan; Ge, Wenzhi; Jia, Lingyu

    2016-01-01

    Low temperature 1H- and 19F-DOSY have been used for analyzing reactive intermediates in glycosylation reactions, where a glycosyl trichloroacetimidate donor has been activated using different catalysts. The DOSY protocols have been optimized for low temperature experiments and provided new insight...

  1. Penicillin resistance and serotype distribution of Streptococcus pneumoniae in Ghanaian children less than six years of age

    DEFF Research Database (Denmark)

    Dayie, Nicholas T. K. D.; Arhin, Reuben E.; Newman, Mercy J.

    2013-01-01

    Background: The objective of this study was to determine the prevalence of nasopharyngeal carriage, serotype distribution, and penicillin resistance of Streptococcus pneumoniae in children 2 mu g/ml and were classified as fully penicillin resistant with 45% of the isolates having intermediate...... serotypes detected. The two penicillin resistant isolates (MIC 32 mu g/ml) were serotypes included in both PCV-13 and PPV-23. A nationwide monitoring system of penicillin susceptibility patterns and pneumococcal serotypes is recommended....

  2. L-subshell ionization studies in Au and Bi for 19F and 28Si large-ion bombardment

    International Nuclear Information System (INIS)

    Padhi, H.C.; Dhal, B.B.; Nanal, V.; Prasad, K.G.; Tandon, P.N.; Trautmann, D.

    1996-01-01

    L x-ray production and subshell ionization cross sections of Au and Bi have been measured for the bombardment of 19 F and 28 Si ions in the energy range 30 endash 57 MeV and 36 endash 84 MeV, respectively. Comparison of the Lα x-ray production cross sections of Au with the earlier data by Malhi and Gray [Phys. Rev. A 44, 7199 (1991)] shows reasonable agreement for 19 F impact and their data are consistently higher for 28 Si at all energies. The measured Lα line energy shows a shift towards higher energy, which appears to be proportional to the square of the projectile atomic number at all impact energies. This shift suggests the presence of multiple ionization in the L and M shells with a simultaneous production of four M holes in Au at the impact energy of 3 MeVu -1 of 28 Si. The L-subshell ionization cross sections obtained from the measured x-ray production cross sections have been compared with the semiclassical approximation and perturbed stationary state theory with energy loss, Coulomb deflection, and relativistic correction for the electron motion calculations, which show large deviations for the L 1 subshell. The L 2 - and L 3 -subshell ionization cross sections are underestimated by both the theories by a factor of 1.2 endash 4.0 for 28 Si impact whereas for the 19 F case there is reasonable agreement for the L 3 cross section but the L 2 cross section is underestimated by 20 endash 30%. copyright 1996 The American Physical Society

  3. DFT-GIAO calculation of properties of 19F NMR and stability study of environmentally relevant perfluoroalkylsulfonamides (PFASAmide)

    International Nuclear Information System (INIS)

    Mejia-Urueta, Rafael; Mestre-Quintero, Kleyber; Vivas-Reyes, Ricardo

    2011-01-01

    Perfluorinated organic compounds (POCs), such as perfluorooctanesulfonate (PFOS) and perfluoroalkylsulfonamide (PFASA) are compounds that have recently attracted considerable attention worldwide because of its high persistence and wide distribution in the environment. Among the spectroscopic methods used to study the PFASA, 19 F nuclear magnetic resonance (NMR 19 F) is very effective, due to its ability to determine concentrations of PFASA in biological samples and measure pollution in water samples. For this reason, a theoretical study of the properties of 19 F NMR was performed. In this study we have determined the shielding constant (σ) for different fluorine nucleus of the 18 molecules under study, using density functional theory (DFT) and GIAO method with the B3PW91/6-31+G(d,p) level of calculation. The σ calculations were made at vacuum and in presence of a solvent. The values of chemical shifts (δ), were also calculated in a different level of theory. The best results were obtained with the level of calculation DFT-GIAO/B3PW91/6-31+G(d,p) by considering the solvent such as dimethylsulfoxide (DMSO), chloroform (CHCl 3 ), acetone (CH 3 COCH 3 ) and methanol (CH 3 OH). The results were interpreted in terms of calculated hardness at DFT/B3PW91/6-31+G(d, p) level. The behaviour of the hardness was higher in the molecules of four carbons PFASA than eight carbons. This explain theoretically resistance of four carbons PFAS to be transformed into perfluorobutanesulfonate (PFBS). (author)

  4. Dengue Virus Serotype 2 Established in Northern Mozambique (2015-2016).

    Science.gov (United States)

    Oludele, John; Lesko, Birgitta; Mahumane Gundane, Isabel; de Bruycker-Nogueira, Fernanda; Muianga, Argentina; Ali, Sadia; Mula, Flora; Chelene, Imelda; Falk, Kerstin I; Barreto Dos Santos, Flávia; Gudo, Eduardo Samo

    2017-11-01

    After the report of an outbreak of dengue virus serotype 2 in 2014 in Nampula and Pemba cities, northern Mozambique, a surveillance system was established by the National Institute of Health. A study was performed during 2015-2016 to monitor the trend of the outbreak and confirm the circulating serotype of dengue virus (DENV). After the inclusion of consenting patients who met the case definition, samples from 192 patients were tested for the presence of nonstructural protein 1 antigen, and 60/192 (31%) samples were positive. Further analysis included DENV IgM antibodies, with 39 (20%) IgM positive cases. Reverse transcriptase (RT) PCR was performed for identification of the prevailing DENV serotype; 21/23 tested samples were DENV-2 positive, with DENV-2 present in both affected cities. When sequencing DENV, phenotype Cosmopolitan was identified. The surveillance indicates ongoing spread of DENV-2 in northern Mozambique 2 years after the first report of the outbreak.

  5. Mapping the polysaccharide degradation potential of Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Andersen Mikael R

    2012-07-01

    Full Text Available Abstract Background The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For each type of hemicellulose, a complex mixture of enzymes is required for complete conversion to fermentable monosaccharides. In plant-biomass degrading fungi, these enzymes are regulated and released by complex regulatory structures. In this study, we present a methodology for evaluating the potential of a given fungus for polysaccharide degradation. Results Through the compilation of information from 203 articles, we have systematized knowledge on the structure and degradation of 16 major types of plant polysaccharides to form a graphical overview. As a case example, we have combined this with a list of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono- and polysaccharide substrates has allowed elucidation of concerted gene expression from this organism. One such example is the identification of a full set of extracellular polysaccharide-acting genes for the degradation of oat spelt xylan. Conclusions The mapping of plant polysaccharide structures along with the corresponding enzymatic activities is a powerful framework for expression analysis of carbohydrate-active enzymes. Applying this network-based approach, we provide the first genome-scale characterization of all genes coding for carbohydrate-active enzymes identified in A. niger.

  6. Serotypes and typability of Campylobacter jejuni and Campylobacter coli isolated from poultry products

    DEFF Research Database (Denmark)

    Nielsen, Eva Møller; Nielsen, Niels Ladefoged

    1999-01-01

    to study the serotype distribution of C. jejuni and C. coli isolated from different food products of poultry origin sampled from retail outlets in Denmark. A total of 156 isolates were serotyped, 85% of these were C. jejuni and 15% were C. coli. The most common C. jejuni serotypes were O:2 (30%), O:1...... nontypable. This rate of nontypable isolates is significantly higher than experienced for isolates from other sources than food products, i.e faecal samples from animals and humans. Subculturing and re-typing of the nontypable isolates improved the typability. After two, five and 10 subcultures 16, six...

  7. Porcine aminopeptidase N binds to F4+ enterotoxigenic Escherichia coli fimbriae.

    Science.gov (United States)

    Xia, Pengpeng; Wang, Yiting; Zhu, Congrui; Zou, Yajie; Yang, Ying; Liu, Wei; Hardwidge, Philip R; Zhu, Guoqiang

    2016-02-09

    F4(+) enterotoxigenic Escherichia coli (ETEC) strains cause diarrheal disease in neonatal and post-weaned piglets. Several different host receptors for F4 fimbriae have been described, with porcine aminopeptidase N (APN) reported most recently. The FaeG subunit is essential for the binding of the three F4 variants to host cells. Here we show in both yeast two-hybrid and pulldown assays that APN binds directly to FaeG, the major subunit of F4 fimbriae, from three serotypes of F4(+) ETEC. Modulating APN gene expression in IPEC-J2 cells affected ETEC adherence. Antibodies raised against APN or F4 fimbriae both reduced ETEC adherence. Thus, APN mediates the attachment of F4(+) E. coli to intestinal epithelial cells.

  8. Comparison of high and low virulence serotypes of Actinobacillus pleuropneumoniae by quantitative real-time PCR

    DEFF Research Database (Denmark)

    Schou, Kirstine Klitgaard; Angen, Øystein; Boye, Mette

    PCR data. Preliminary results showed that in both serotype 2 and serotype 6, the toxin producing gene apxIV was the most highly expressed of the investigated genes. The major difference observed between the two serotypes was that apfA, involved in type IV vili production, was significantly upregulated...... of high virulence while serotype 6 strains are normally found to be less pathogenic. To gain an understanding of the differential virulence of serotype 2 and 6, the expression of a panel of Ap genes during infection of porcine epithelial lung cells (SJPL) were examined by quantitative real-time PCR (q...... to be important for early establishment of the bacteria in the host were examined by qPCR. The genes examined were apfA, coding for a subunit of Type IV pili, kdsB coding for a gene involved in lippopolysacceride biosynthesis, and pgaB which is involved in biofilm formation, all three believed to be important...

  9. Direct 19F NMR observation of the conformational selection of optically active rotamers of the antifolate compound fluoronitropyrimethamine bound to enzyme dihydrofolate reductase

    International Nuclear Information System (INIS)

    Tendler, S.J.B.; Birdsall, B.; Feeney, J.; Griffin, R.J.; Stevens, M.F.G.; Roberts, G.C.K.

    1988-01-01

    The molucular basis of the binding of the lipophilic antifolate compound fluoronitropyrimethamine to its target enzyme dihydrofolate reductase has been investigated using a combination of 19 F NMR spectroscopy and molecular mechanical calculations 19 F NMR reveals the presence of two different conformational states for the fluoronitropyrimethamine-Lactobacillus casei enzyme complex. MM2 molecular mechanical calculations predict restricted rotation about the C5-C1 bond of the ligand and this give rise to two slowly interconverting rotamers which are an enantiomeric pair. The results of 19 F NMR spectroscopy reveal that both these isomers bind to the enzyme, with different affinities. There is no detectable interconversion of the bound rotamers themselves on the NMR timescale. The effect of the addition of co-enzyme to the sample is to reverse the preference the enzyme has for each rotamer. (author). 11 refs.; 3 figs

  10. Genetic Characterization of Serotypes A and Asia-1 Foot-and-mouth Disease Viruses in Balochistan, Pakistan, in 2011.

    Science.gov (United States)

    Ullah, A; Jamal, S M; Romey, A; Gorna, K; Kakar, M A; Abbas, F; Ahmad, J; Zientara, S; Bakkali Kassimi, L

    2017-10-01

    This study reports characterization of foot-and-mouth disease virus (FMDV) in samples collected from Balochistan, Pakistan. FMDV was detected by pan-FMDV real-time RT-PCR in 31 samples (epithelial and oral swabs) collected in 2011 from clinical suspect cases. Of these, 29 samples were serotyped by serotype-specific real-time RT-PCR assays and were confirmed by sequencing the VP1 coding region. Sixteen samples were found positive for serotype A and eight for serotype Asia-1, whereas five samples were found positive for both serotypes A and Asia-1. Two serotype A positive samples were found positive for two different strains of serotype A FMDV each. Phylogenetic analyses of serotype A FMDVs showed circulation of at least three different sublineages within the A-Iran05 lineage. These included two earlier reported sublineages, A-Iran05 HER -10 and A-Iran05 FAR -11 , and a new sublineage, designated here as A-Iran05 BAL -11 . This shows that viruses belonging to the A-Iran05 lineage are continuously evolving in the region. Viruses belonging to the A-Iran05 FAR -11 sublineage showed close identity with the viruses circulating in 2009 in Pakistan and Afghanistan. However, viruses belonging to the A-Iran05 HER -10 detected in Balochistan, Pakistan, showed close identity with the viruses circulating in Kyrgyzstan, Iran and Kazakhstan in 2011 and 2012, showing that viruses responsible for outbreak in these countries have a common origin. Serotype Asia-1 FMDVs reported in this study all belonged to the earlier reported Group-VII (Sindh-08), which is currently a dominant strain in the West Eurasian region. Detection of two different serotypes of FMDV or/and two different strains of the same serotype in one animal/sample shows complexity in occurrence of FMD in the region. © 2016 Blackwell Verlag GmbH.

  11. Modulating surface rheology by electrostatic protein/polysaccharide interactions

    NARCIS (Netherlands)

    Ganzevles, R.A.; Zinoviadou, K.; Vliet, van T.; Cohen Stuart, M.A.; Jongh, de H.H.J.

    2006-01-01

    There is a large interest in mixed protein/polysaccharide layers at air-water and oil-water interfaces because of their ability to stabilize foams and emulsions. Mixed protein/polysaccharide adsorbed layers at air-water interfaces can be prepared either by adsorption of soluble protein/

  12. Maca polysaccharides: A review of compositions, isolation, therapeutics and prospects.

    Science.gov (United States)

    Li, Yujuan; Xu, Fangxue; Zheng, Mengmeng; Xi, Xiaozhi; Cui, Xiaowei; Han, Chunchao

    2018-05-01

    Maca polysaccharides, some of the major bioactive substances in Lepidium meyenii (Walp.) (Maca), have various biological properties, including anti-oxidant, anti-fatigue, anti-tumor, and immunomodulatory effects, as well as hepatoprotective activity and regulation function. Although many therapeutics depend on multiple structures of maca polysaccharides in addition to providing sufficient foundations for maca polysaccharide products in industrial applications, the relationships between the pharmacological effects and structures have not been established. Therefore, this article summarizes the extraction and purification methods, compositions, pharmacological effects, prospects and industrial applications of maca polysaccharides. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. First human case report of sepsis due to infection with Streptococcus suis serotype 31 in Thailand.

    Science.gov (United States)

    Hatrongjit, Rujirat; Kerdsin, Anusak; Gottschalk, Marcelo; Takeuchi, Dan; Hamada, Shigeyuki; Oishi, Kazunori; Akeda, Yukihiro

    2015-09-30

    Streptococcus suis is a zoonotic pathogen that causes invasive infections in humans and pigs. It has been reported that S. suis infection in humans is mostly caused by serotype 2. However, human cases caused by other serotypes have rarely been reported. This is the first report of a human case of infection with S. suis serotype 31 in Thailand. A 55-year-old male alcohol misuser with liver cirrhosis was admitted with sepsis to a hospital in the Central Region of Thailand. He had consumed a homemade, raw pork product prior to the onset of illness. He was alive after treatment with ceftriaxone and no complication occurred. An isolate from blood culture at the hospital was suspected as viridans group Streptococcus. It was confirmed at a reference laboratory as S. suis serotype 31 by biochemical tests, 16S rDNA sequencing, and multiplex polymerase chain reaction for serotyping, but it was untypable by the co-agglutination test with antisera against recognized S. suis serotypes, suggesting loss of capsular material. The absence of a capsule was confirmed by transmission electron microscopy. The isolate was confirmed to be sequence type 221, with 13 putative virulence genes that are usually found in serotype 2 strains. We should be aware of the emergence of S. suis infections caused by uncommon serotypes in patients with predisposing conditions. Laboratory capacity to identify S. suis in the hospital is needed in developing countries, which can contribute to enhanced surveillance, epidemiological control, and prevention strategies in the prevalent area.

  14. Molecular characterization of Orientia tsutsugamushi serotypes causing scrub typhus outbreak in southern region of Andhra Pradesh, India.

    Science.gov (United States)

    Usha, K; Kumar, E; Kalawat, Usha; Kumar, B Siddhartha; Chaudhury, A; Gopal, D V R Sai

    2016-10-01

    Scrub typhus is a vector-borne zoonotic infection caused by Orientiatsutsugamushi. Local epidemiology of the circulating serotypes of scrub typhus is not available from most parts of India. We conducted this study for the diagnosis of scrub typhus using IgM ELISA and to detect O. tsutsugamushi serotypes circulating in southern Andhra Pradesh, India. Samples were collected from patients clinically suspected to have scrub typhus and were subjected to IgM ELISA to measure IgM antibodies against O. tsutsugamushi. Nested polymerase chain reaction (PCR) was performed targeting strain-specific regions in ELISA-positive samples. Of a total of 663 samples, 258 (38.91%) were found to be positive by IgM ELISA. Serotypes could be detected in 230 (34.69%) samples only. Only two serotypes, Karp and Kawasaki, were found in the serum samples, with the former being predominant. The dual infection of Karp and Kawasaki serotypes was found in seven patients. Other serotypes such as Gilliam, Kuroki and Kato were not detected in the samples. The nested PCR products proved useful in presumptively identifying the endemic O. tsutsugamushi serotypes. The present study could be significant in understanding scrub typhus epidemiology in this region.

  15. Ulva lactuca polysaccharides prevent Wistar rat breast carcinogenesis through the augmentation of apoptosis, enhancement of antioxidant defense system, and suppression of inflammation

    Directory of Open Access Journals (Sweden)

    Abd-Ellatef GF

    2017-02-01

    Full Text Available Gamal-Eldein F Abd-Ellatef,1 Osama M Ahmed,2 Eman S Abdel-Reheim,2 Abdel-Hamid Z Abdel-Hamid,1 1Pharmaceutical and Drug Industries Research Division, Therapeutic Chemistry Department, National Research Centre, Cairo, Egypt; 2Division of Physiology, Department of Zoology, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt Background: Recently, several research studies have been focused on the isolation and function of the polysaccharides derived from different algal species, which revealed multiple biological activities such as antioxidant and antitumor activities. This study assesses the possible breast cancer chemopreventive properties of common seaweeds, sea lettuce, Ulva lactuca (ulvan polysaccharides using in vitro bioassays on human breast cancer cell line (MCF-7 and an in vivo animal model of breast carcinogenesis. Methods: Cytotoxic effect of ulvan polysaccharides on MCF-7 was tested in vitro. For an in vivo investigation, a single dose of 25 mg/kg body weight 7,12-dimethylbenz[a]anthracene (DMBA and ulvan polysaccharides (50 mg/kg body weight every other day for 10 weeks were administered orally to the Wistar rats. Results: Deleterious histopathological alterations in breast tissues including papillary cyst adenoma and hyperplasia of ductal epithelial lining with intraluminal necrotic materials and calcifications were observed in the DMBA-administered group. These lesions were prevented in the DMBA-administered group treated with ulvan polysaccharides. The immunohistochemical sections depicted that the treatment of DMBA-administered rats with ulvan polysaccharides markedly increased the lowered pro-apoptotic protein, p53, and decreased the elevated anti-apoptotic marker, bcl2, expression in the breast tissue. The elevated lipid peroxidation and the suppressed antioxidant enzyme activities in DMBA-administered control were significantly prevented by the treatment with ulvan polysaccharides. The elevated levels of inflammatory

  16. Extraction, characterization and antioxidant activities of Se-enriched tea polysaccharides.

    Science.gov (United States)

    Wang, Yuanfeng; Li, Yongfu; Liu, Yangyang; Chen, Xueqing; Wei, Xinlin

    2015-01-01

    Se-polysaccharides from Se-enriched tea leaves were purified by DEAE-sepharose fast flow gel column (2.5×60cm) and three polysaccharide fractions (Se-TPS1, Se-TPS2, and Se-TPS3) were isolated and purified with yields of 6.5, 37.14, and 8.57%, respectively. The average sizes of Se-TPS1 and Se-TPS2 were determined by HPGPC system, with molecular weights of 1.1×10(5) and 2.4×10(5)Da, respectively. Se-TPS3 was a polysaccharide polymer with two peaks with molecular weights of 9.2×10(5) and 2.5×10(5)Da. Monosaccharide components analysis by ion chromatography revealed Se-polysaccharides were acidic polysaccharoses and different from each other in monosaccharide kinds and molar ratio. Elements of Se, C, H, N, S, and 14 kinds of mineral elements were analyzed by AFS, EA, and ICP-AES, respectively. Spectral analysis (IR and UV) indicated Se-polysaccharides were typical glycoproteins. Morphological analyses of the samples were determined by SEM and AFM. In addition, the DPPH and superoxide radicals scavenging activities were also discussed to assess antioxidant activities of the samples, and Se-polysaccharides showed higher antioxidant activities compared to the ordinary polysaccharides. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Novel chimeric foot-and-mouth disease virus-like particles harboring serotype O VP1 protect guinea pigs against challenge.

    Science.gov (United States)

    Li, Haitao; Li, Zhiyong; Xie, Yinli; Qin, Xiaodong; Qi, Xingcai; Sun, Peng; Bai, Xingwen; Ma, Youji; Zhang, Zhidong

    2016-02-01

    Foot-and-mouth disease is a highly contagious, acute viral disease of cloven-hoofed animal species causing severe economic losses worldwide. Among the seven serotypes of foot-and-mouth disease virus (FMDV), serotype O is predominant, but its viral capsid is more acid sensitive than other serotypes, making it more difficult to produce empty serotype O VLPs in the low pH insect hemolymph. Therefore, a novel chimeric virus-like particle (VLP)-based candidate vaccine for serotype O FMDV was developed and characterized in the present study. The chimeric VLPs were composed of antigenic VP1 from serotype O and segments of viral capsid proteins from serotype Asia1. These VLPs elicited significantly higher FMDV-specific antibody levels in immunized mice than did the inactivated vaccine. Furthermore, the chimeric VLPs protected guinea pigs from FMDV challenge with an efficacy similar to that of the inactivated vaccine. These results suggest that chimeric VLPs have the potential for use in vaccines against serotype O FMDV infection. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004

    Directory of Open Access Journals (Sweden)

    P. G. Howell

    2008-08-01

    Full Text Available Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6% and 34.7%, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and localized in fections affecting only individual horses. This study of the seasonal prevalence of equine encephalosis virus has a corollary and serves as a useful model in the seasonal incidence of the serotypes of African horse sickness and bluetongue in regions where the respective diseases are endemic.

  19. Production of heterologous storage polysaccharides in potato plants

    NARCIS (Netherlands)

    Huang, X.; Vincken, J.P.; Visser, R.G.F.; Trindade, L.M.

    2011-01-01

    Starch is the most important storage polysaccharide in higher plants. This polysaccharide is used in many industrial applications as it is abundant, renewable and biodegradable and it can be modified into a wide range of products used in food, animal feed, pharmaceuticals and industry. With the

  20. Ultrasonic-assisted extraction and in vitro antioxidant activity of polysaccharides from Agaricus bisporus.

    Science.gov (United States)

    Qiao, De-Liang; Zhao, Feng; Huang, Hai-Zhong; Fan, Chun-Chun; Han, Lei

    2012-08-01

    To optimize ultrasonic-assisted extraction parameters of polysaccharides from Agaricus bisporus and evaluate antioxidant activities of A. bisporus polysaccharides. Polysaccharides from A. bisporus was extracted by using methods of ultrasonic-assisted hot water lixiviation, ethanol precipitation, Sevag's deproteination and ethanol precipitation again. Extraction temperature, extraction time, ratio of water to raw material and ultrasonic power were selected in single-factor tests. Based on the single-factor tests, parameters combination for the ultrasonic-assisted extraction of A. bisporus polysaccharides was optimized by using four-factor-three-level orthogonal test. Antioxidant activities (reductive potential, superoxide anion scavenging activity and H2O2 scavenging activity) of A. bisporus polysaccharides were evaluated in vitro. Optimum conditions for the extracting of A. bisporus polysaccharides were extracting temperature 65 degrees C, extracting time 40 min, ratio of water to raw material 30 mL/g and ultrasonic power 170 w. Practicing this optimal condition, extraction yield of polysaccharides from A. bisporus was 5.6 014%. In crude polysaccharides of A. bisporus, carbohydrates content, determined by applying the phenol-sulfuric acid method, was 75.48%. Polysaccharides of A. bisporus could reduce ferric ion, scavenge superoxide anion and hydrogen peroxide in a dose-dependent manner. Utrasonic-assisted extraction could be used in the extracting of A. bisporus polysaccharides. Polysaccharides of A. bisporus, had direct and potent antioxidant activities, might be developed and utilized as natural antioxidant.

  1. Comparison of Polysaccharides from Two Species of Ganoderma

    Directory of Open Access Journals (Sweden)

    Yu-Ping Tang

    2012-01-01

    Full Text Available Ganoderma lucidum and Ganoderma sinense, known as Lingzhi in Chinese, are commonly used Chinese medicines with excellent beneficial health effects. Triterpenes and polysaccharides are usually considered as their main active components. However, the content of triterpenes differs significantly between the two species of Ganoderma. To date, a careful comparison of polysaccharides from the two species of Ganoderma has not been performed. In this study, polysaccharides from fruiting bodies of two species of Lingzhi collected from different regions of China were analyzed and compared based on HPSEC-ELSD and HPSEC-MALLS-RI analyses, as well as enzymatic digestion and HPTLC of acid hydrolysates. The results indicated that both the HPSEC-ELSD profiles and the molecular weights of the polysaccharides were similar. Enzymatic digestion showed that polyshaccharides from all samples of Lingzhi could be hydrolyzed by pectinase and dextranase. HPTLC profiles of their TFA hydrolysates colored with different reagents and their monosaccharides composition were also similar.

  2. Inhibitory Effects of Various Ratios of Polysaccharides/Alkaloids from ...

    African Journals Online (AJOL)

    and increases survival in endotoxemic mice. Acta. Pharmacol Sin ... secretion in hyperthyroid diarrheic rats. Regul Peptides ... effect of Coptis chinensis polysaccharide in high-fat diet ... polysaccharides decrease blood sugar by inhibition of α-.

  3. Sulfated Polysaccharides in Marine Sponges: Extraction Methods and Anti-HIV Activity

    Directory of Open Access Journals (Sweden)

    Ana I. S. Esteves

    2011-01-01

    Full Text Available The extraction, fractionation and HIV-1 inhibition potential of polysaccharides extracted from three species of marine sponges, Erylus discophorus, Cliona celata and Stelletta sp., collected in the Northeastern Atlantic, is presented in this work. The anti-HIV activity of 23 polysaccharide pellets and three crude extracts was tested. Crude extracts prepared from Erylus discophorus specimens were all highly active against HIV-1 (90 to 95% inhibition. Cliona celata pellets showed low polysaccharide content (bellow 38.5% and almost no anti-HIV activity (<10% inhibition. Stelletta sp. pellets, although quite rich in polysaccharide (up to 97.3%, showed only modest bioactivity (<36% HIV-1 inhibition. Erylus discophorus pellets were among the richest in terms of polysaccharide content (up to 98% and the most active against HIV-1 (up to 95% inhibition. Chromatographic fractionation of the polysaccharide pellet obtained from a specimen of Erylus discophorus (B161 yielded only modestly active fractions. However, we could infer that the active molecule is most probably a high molecular weight sulfated polysaccharide (>2000 kDa, whose mechanism is possibly preventing viral attachment and entry (fusion inhibitor.

  4. Quantitative comparison of intestinal invasion of zoonotic serotypes of Salmonella enterica in poultry

    DEFF Research Database (Denmark)

    Aabo, Søren; Christensen, J.P.; Chadfield, M.S.

    2002-01-01

    A. Two serotypes demonstrated intracellular log(10) counts that differed significantly from all other serotypes tested: Salmonella Enteritidis PT4 being 1.5 log(10) colony forming units (CFU) ( 31-fold) higher, and Salmonella Tennessee being 0.7 log(10) CFU (fivefold) lower than the reference strain (P...

  5. Phenotypes, serotypes and antibiotic susceptibility of Swedish Porphyromonas gingivalis isolates from periodontitis and periodontal abscesses.

    Science.gov (United States)

    Dahlén, G; Gmür, R; Yoshino, T

    2007-04-01

    This study was conducted to reveal phenotypic, serological subtypes and antibiotic susceptibility among fresh isolates of Porphyromonas gingivalis in a Swedish population with periodontitis and periodontal abscess. Fifty-five subgingival strains were isolated and tentatively designated as P. gingivalis from 55 consecutive paper-point samples taken from 51 patients with periodontitis (at least one site with >6-mm pocket depth) in Sweden and were sent in for microbiological evaluation. Eight P. gingivalis strains from periodontal abscesses were also included. Four P. gingivalis strains served as reference and another four type strains were included. The strains were characterized by colony morphology, biochemical tests, enzyme profile, gas-liquid chromatography and antibiotic susceptibility. The strains were further characterized for whole cell protein profiles using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and were identified to serotype by specific monoclonal antibodies. Among the 55 P. gingivalis strains 35 had smooth (S), 13 rough (R) and seven semi-rough colony morphologies. All strains were phenotypically homogeneous in biochemical tests, enzyme profile and antibiotic susceptibility. All strains produced phenylacetic acid and alpha-fucosidase. Almost all (96%) of the subgingival strains, but relatively fewer (62%) of the abscess strains, belonged to serotype A. Two subgingival and three abscess strains were classified as serotype B. No specific SDS-PAGE protein profiles were recorded for the two serotypes. The P. gingivalis strains from Swedish periodontitis cases showed homogeneity in terms of biochemical phenotypes and antibiotic susceptibility patterns. The strains fell into two serotypes, of which serotype A predominated in the periodontitis cases and serotype B was overrepresented in periodontal abscesses.

  6. Genetic diversity of clinical and environmental strains of Salmonella enterica serotype Weltevreden isolated in Malaysia.

    Science.gov (United States)

    Thong, K L; Goh, Y L; Radu, S; Noorzaleha, S; Yasin, R; Koh, Y T; Lim, V K E; Rusul, G; Puthucheary, S D

    2002-07-01

    The incidence of food-borne salmonellosis due to Salmonella enterica serotype Weltevreden is reported to be on the increase in Malaysia. The pulsed-field gel electrophoresis (PFGE) subtyping method was used to assess the extent of genetic diversity and clonality of Salmonella serotype Weltevreden strains from humans and the environment. PFGE of XbaI-digested chromosomal DNA from 95 strains of Salmonella serotype Weltevreden gave 39 distinct profiles with a wide range of Dice coefficients (0.27 to 1.00), indicating that PFGE is very discriminative and that multiple clones of Salmonella serotype Weltevreden exist among clinical and environmental isolates. Strains of one dominant pulsotype (pulsotype X1/X2) appeared to be endemic in this region, as they were consistently recovered from humans with salmonellosis between 1996 and 2001 and from raw vegetables. In addition, the sharing of similar PFGE profiles among isolates from humans, vegetables, and beef provides indirect evidence of the possible transmission of salmonellosis from contaminated raw vegetables and meat to humans. Furthermore, the recurrence of PFGE profile X21 among isolates found in samples of vegetables from one wet market indicated the persistence of this clone. The environment in the wet markets may represent a major source of cross-contamination of vegetables with Salmonella serotype Weltevreden. Antibiotic sensitivity tests showed that the clinical isolates of Salmonella serotype Weltevreden remained drug sensitive but that the vegetable isolates were resistant to at least two antibiotics. To the best of our knowledge, this is the first study to compare clinical and environmental isolates of Salmonella serotype Weltevreden in Malaysia.

  7. Genetic Diversity of Clinical and Environmental Strains of Salmonella enterica Serotype Weltevreden Isolated in Malaysia

    Science.gov (United States)

    Thong, K. L.; Goh, Y. L.; Radu, S.; Noorzaleha, S.; Yasin, R.; Koh, Y. T.; Lim, V. K. E.; Rusul, G.; Puthucheary, S. D.

    2002-01-01

    The incidence of food-borne salmonellosis due to Salmonella enterica serotype Weltevreden is reported to be on the increase in Malaysia. The pulsed-field gel electrophoresis (PFGE) subtyping method was used to assess the extent of genetic diversity and clonality of Salmonella serotype Weltevreden strains from humans and the environment. PFGE of XbaI-digested chromosomal DNA from 95 strains of Salmonella serotype Weltevreden gave 39 distinct profiles with a wide range of Dice coefficients (0.27 to 1.00), indicating that PFGE is very discriminative and that multiple clones of Salmonella serotype Weltevreden exist among clinical and environmental isolates. Strains of one dominant pulsotype (pulsotype X1/X2) appeared to be endemic in this region, as they were consistently recovered from humans with salmonellosis between 1996 and 2001 and from raw vegetables. In addition, the sharing of similar PFGE profiles among isolates from humans, vegetables, and beef provides indirect evidence of the possible transmission of salmonellosis from contaminated raw vegetables and meat to humans. Furthermore, the recurrence of PFGE profile X21 among isolates found in samples of vegetables from one wet market indicated the persistence of this clone. The environment in the wet markets may represent a major source of cross-contamination of vegetables with Salmonella serotype Weltevreden. Antibiotic sensitivity tests showed that the clinical isolates of Salmonella serotype Weltevreden remained drug sensitive but that the vegetable isolates were resistant to at least two antibiotics. To the best of our knowledge, this is the first study to compare clinical and environmental isolates of Salmonella serotype Weltevreden in Malaysia. PMID:12089269

  8. [Analysis of thickening polysaccharides by the improved diethyldithioacetal derivatization method].

    Science.gov (United States)

    Akiyama, Takumi; Yamazaki, Takeshi; Tanamoto, Kenichi

    2011-01-01

    The identification test for thickening polysaccharides containing neutral saccharides and uronic acids was investigated by GC analysis of constituent monosaccharides. The reported method, in which monosaccharides were converted to diethyldithioacetal derivatives with ethanethiol followed by trimethylsilylation, was improved in terms of operability and reproducibility of GC/MS analysis. The suitability of the improved diethyldithioacetal derivatization method was determined for seven thickening polysaccharides, i.e., carob bean gum, guar gum, karaya gum, gum arabic, gum ghatti, tragacanth gum and peach gum. The samples were acid-hydrolyzed to form monosaccharides. The hydrolysates were derivatized and analyzed with GC/FID. Each sugar derivative was detected as a single peak and was well separated from others on the chromatograms. The amounts of constituent monosaccharides in thickening polysaccharides were successfully estimated. Seven polysaccharides were distinguished from each other on the basis of constituent monosaccharides. Further examination of the time period of hydrolysis of polysaccharides using peach gum showed that the optimal times were not the same for all monosaccharides. A longer time was needed to hydrolyze glucuronic acid than neutral saccharides. The findings suggest that hydrolysis time may sometimes affect the analytical results on composition of constituent monosaccharides in polysaccharides.

  9. Recent Advances in Marine Algae Polysaccharides: Isolation, Structure, and Activities.

    Science.gov (United States)

    Xu, Shu-Ying; Huang, Xuesong; Cheong, Kit-Leong

    2017-12-13

    Marine algae have attracted a great deal of interest as excellent sources of nutrients. Polysaccharides are the main components in marine algae, hence a great deal of attention has been directed at isolation and characterization of marine algae polysaccharides because of their numerous health benefits. In this review, extraction and purification approaches and chemico-physical properties of marine algae polysaccharides (MAPs) are summarized. The biological activities, which include immunomodulatory, antitumor, antiviral, antioxidant, and hypolipidemic, are also discussed. Additionally, structure-function relationships are analyzed and summarized. MAPs' biological activities are closely correlated with their monosaccharide composition, molecular weights, linkage types, and chain conformation. In order to promote further exploitation and utilization of polysaccharides from marine algae for functional food and pharmaceutical areas, high efficiency, and low-cost polysaccharide extraction and purification methods, quality control, structure-function activity relationships, and specific mechanisms of MAPs activation need to be extensively investigated.

  10. Two complex, adenovirus-based vaccines that together induce immune responses to all four dengue virus serotypes.

    Science.gov (United States)

    Holman, David H; Wang, Danher; Raviprakash, Kanakatte; Raja, Nicholas U; Luo, Min; Zhang, Jianghui; Porter, Kevin R; Dong, John Y

    2007-02-01

    Dengue virus infections can cause hemorrhagic fever, shock, encephalitis, and even death. Worldwide, approximately 2.5 billion people live in dengue-infested regions with about 100 million new cases each year, although many of these infections are believed to be silent. There are four antigenically distinct serotypes of dengue virus; thus, immunity from one serotype will not cross-protect from infection with the other three. The difficulties that hamper vaccine development include requirements of the natural conformation of the envelope glycoprotein to induce neutralizing immune responses and the necessity of presenting antigens of all four serotypes. Currently, the only way to meet these requirements is to use a mixture of four serotypes of live attenuated dengue viruses, but safety remains a major problem. In this study, we have developed the basis for a tetravalent dengue vaccine using a novel complex adenovirus platform that is capable of expressing multiple antigens de novo. This dengue vaccine is constructed as a pair of vectors that each expresses the premembrane and envelope genes of two different dengue virus serotypes. Upon vaccination, the vaccine expressed high levels of the dengue virus antigens in cells to mimic a natural infection and induced both humoral and cellular immune responses against multiple serotypes of dengue virus in an animal model. Further analyses show the humoral responses were indeed neutralizing against all four serotypes. Our studies demonstrate the concept of mimicking infections to induce immune responses by synthesizing dengue virus membrane antigens de novo and the feasibility of developing an effective tetravalent dengue vaccine by vector-mediated expression of glycoproteins of the four serotypes.

  11. Synthesis, characterization and evaluation of thiolated tamarind seed polysaccharide as a mucoadhesive polymer.

    Science.gov (United States)

    Kaur, Harmanmeet; Yadav, Shikha; Ahuja, Munish; Dilbaghi, Neeraj

    2012-11-06

    In the present study, thiol-functionalization of tamarind seed polysaccharide was carried out by esterification with thioglycolic acid. Thiol-functionalization was confirmed by SH stretch in Fourier-transformed infra-red spectra at 2586 cm(-1). It was found to possess 104.5 mM of thiol groups per gram. The results of differential scanning calorimetry and X-ray diffraction study indicate increase in crystallinity. Polymer compacts of thiolated tamarind seed polysaccharide required 6.85-fold greater force to detach from the mucin coated membrane than that of tamarind seed polysaccharide. Comparative evaluation of Carbopol-based metronidazole gels containing thiolated tamarind seed polysaccharide with gels containing tamarind seed polysaccharide for mucoadhesive strength using chicken ileum by modified balance method revealed higher mucoadhesion of gels containing thiolated tamarind seed polysaccharide. Further, the gels containing tamarind seed polysaccharide and thiolated tamarind seed polysaccharide released the drug by Fickian-diffusion following the first-order and Higuchi's-square root release kinetics, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Polysaccharide-Based Membranes in Food Packaging Applications

    Directory of Open Access Journals (Sweden)

    Ana R. V. Ferreira

    2016-04-01

    Full Text Available Plastic packaging is essential nowadays. However, the huge environmental problem caused by landfill disposal of non-biodegradable polymers in the end of life has to be minimized and preferentially eliminated. The solution may rely on the use of biopolymers, in particular polysaccharides. These macromolecules with film-forming properties are able to produce attracting biodegradable materials, possibly applicable in food packaging. Despite all advantages of using polysaccharides obtained from different sources, some drawbacks, mostly related to their low resistance to water, mechanical performance and price, have hindered their wider use and commercialization. Nevertheless, with increasing attention and research on this field, it has been possible to trace some strategies to overcome the problems and recognize solutions. This review summarizes some of the most used polysaccharides in food packaging applications.

  13. Polysaccharide-Based Membranes in Food Packaging Applications

    Science.gov (United States)

    Ferreira, Ana R. V.; Alves, Vítor D.; Coelhoso, Isabel M.

    2016-01-01

    Plastic packaging is essential nowadays. However, the huge environmental problem caused by landfill disposal of non-biodegradable polymers in the end of life has to be minimized and preferentially eliminated. The solution may rely on the use of biopolymers, in particular polysaccharides. These macromolecules with film-forming properties are able to produce attracting biodegradable materials, possibly applicable in food packaging. Despite all advantages of using polysaccharides obtained from different sources, some drawbacks, mostly related to their low resistance to water, mechanical performance and price, have hindered their wider use and commercialization. Nevertheless, with increasing attention and research on this field, it has been possible to trace some strategies to overcome the problems and recognize solutions. This review summarizes some of the most used polysaccharides in food packaging applications. PMID:27089372

  14. Genetic Diversity of Clinical and Environmental Strains of Salmonella enterica Serotype Weltevreden Isolated in Malaysia

    OpenAIRE

    Thong, K. L.; Goh, Y. L.; Radu, S.; Noorzaleha, S.; Yasin, R.; Koh, Y. T.; Lim, V. K. E.; Rusul, G.; Puthucheary, S. D.

    2002-01-01

    The incidence of food-borne salmonellosis due to Salmonella enterica serotype Weltevreden is reported to be on the increase in Malaysia. The pulsed-field gel electrophoresis (PFGE) subtyping method was used to assess the extent of genetic diversity and clonality of Salmonella serotype Weltevreden strains from humans and the environment. PFGE of XbaI-digested chromosomal DNA from 95 strains of Salmonella serotype Weltevreden gave 39 distinct profiles with a wide range of Dice coefficients (0.2...

  15. The differential impact of oral poliovirus vaccine formulation choices on serotype-specific population immunity to poliovirus transmission.

    Science.gov (United States)

    Thompson, Kimberly M; Duintjer Tebbens, Radboud J

    2015-09-17

    Prior analyses demonstrated the need for some countries and the Global Polio Eradication Initiative (GPEI) to conduct additional supplemental immunization activities (SIAs) with trivalent oral poliovirus vaccine (tOPV) prior to globally-coordinated cessation of all serotype 2-containing OPV (OPV2 cessation) to prevent the creation of serotype 2 circulating vaccine-derived poliovirus (cVDPV2) outbreaks after OPV2 cessation. The GPEI continues to focus on achieving and ensuring interruption of wild poliovirus serotype 1 (WPV1) and making vaccine choices that prioritize bivalent OPV (bOPV) for SIAs, nominally to increase population immunity to serotype 1, despite an aggressive timeline for OPV2 cessation. We use an existing dynamic poliovirus transmission model of northwest Nigeria and an integrated global model for long-term poliovirus risk management to explore the impact of tOPV vs. bOPV vaccine choices on population immunity and cVDPV2 risks. Using tOPV instead of bOPV for SIAs leads to a minimal decrease in population immunity to transmission of serotypes 1 and 3 polioviruses, but a significantly higher population immunity to transmission of serotype 2 polioviruses. Failure to use tOPV in enough SIAs results in cVDPV2 emergence after OPV2 cessation in both the northwest Nigeria model and the global model. Despite perceptions to the contrary, prioritizing the use of bOPV over tOPV prior to OPV2 cessation does not significantly improve serotype 1 population immunity to transmission. Immunization leaders need to focus on all three poliovirus serotypes to appropriately manage the risks of OPV cessation in the polio endgame. Focusing on population immunity to transmission to interrupt WPV1 transmission and manage pre-OPV cessation risks of cVDPVs, all countries performing poliovirus SIAs should use tOPV up until the time of OPV2 cessation, after which time they should continue to use the OPV vaccine formulation with all remaining serotypes until coordinated global

  16. Biophysical functionality in polysaccharides: from Lego-blocks to nano-particles.

    Science.gov (United States)

    Cesàro, Attilio; Bellich, Barbara; Borgogna, Massimiliano

    2012-04-01

    The objective of the paper is to show the very important biophysical concepts that have been developed with polysaccharides. In particular, an attempt will be made to relate "a posteriori" the fundamental aspects, both experimental and theoretical, with some industrial applications of polysaccharide-based materials. The overview of chain conformational aspects includes relationships between topological features and local dynamics, exemplified for some naturally occurring carbohydrate polymers. Thus, by using simulation techniques and computational studies, the physicochemical properties of aqueous solutions of polysaccharides are interpreted. The relevance of conformational disorder-order transitions, chain aggregation, and phase separation to the underlying role of the ionic contribution to these processes is discussed. We stress the importance of combining information from analysis of experimental data with that from statistical-thermodynamic models for understanding the conformation, size, and functional stability of industrially important polysaccharides. The peculiar properties of polysaccharides in industrial applications are summarized for the particularly important example of nanoparticles production, a field of growing relevance and scientific interest.

  17. Structural Features and Healthy Properties of Polysaccharides Occurring in Mushrooms

    Directory of Open Access Journals (Sweden)

    Eva Guillamón

    2012-12-01

    Full Text Available Polysaccharides from mushrooms have attracted a great deal of attention due to the many healthy benefits they have demonstrated, such as immunomodulation, anticancer activity, prevention and treatment of cardiovascular diseases, antiviral and antimicrobial effects, among others. Isolation and purification of polysaccharides commonly involve several steps, and different techniques are actually available in order to increase extraction yield and purity. Studies have demonstrated that the molecular structure and arrangement significantly influence the biological activity; therefore, there is a wide range of analytical techniques for the elucidation of chemical structures. Different polysaccharides have been isolated from mushrooms, most of them consisting of β-linked glucans, such as lentinan from Lentinus edodes, pleuran from Pleurotus species, schizophyllan from Schizophyllum commune, calocyban from Calocybe indica, or ganoderan and ganopoly from Ganoderma lucidum. This article reviews the main methods of polysaccharide isolation and structural characterization, as well as some of the most important polysaccharides isolated from mushrooms and the healthy benefits they provide.

  18. Marine Derived Polysaccharides for Biomedical Applications: Chemical Modification Approaches

    Directory of Open Access Journals (Sweden)

    Paola Laurienzo

    2008-09-01

    Full Text Available Polysaccharide-based biomaterials are an emerging class in several biomedical fields such as tissue regeneration, particularly for cartilage, drug delivery devices and gelentrapment systems for the immobilization of cells. Important properties of the polysaccharides include controllable biological activity, biodegradability, and their ability to form hydrogels. Most of the polysaccharides used derive from natural sources; particularly, alginate and chitin, two polysaccharides which have an extensive history of use in medicine, pharmacy and basic sciences, and can be easily extracted from marine plants (algae kelp and crab shells, respectively. The recent rediscovery of poly-saccharidebased materials is also attributable to new synthetic routes for their chemical modification, with the aim of promoting new biological activities and/or to modify the final properties of the biomaterials for specific purposes. These synthetic strategies also involve the combination of polysaccharides with other polymers. A review of the more recent research in the field of chemical modification of alginate, chitin and its derivative chitosan is presented. Moreover, we report as case studies the results of our recent work concerning various different approaches and applications of polysaccharide-based biomaterials, such as the realization of novel composites based on calcium sulphate blended with alginate and with a chemically modified chitosan, the synthesis of novel alginate-poly(ethylene glycol copolymers and the development of a family of materials based on alginate and acrylic polymers of potential interest as drug delivery systems.

  19. Dot Blot para determinar la identidad antigénica en vacunas conjugadas contra Streptococcus pneumoniae serotipo 19F

    Directory of Open Access Journals (Sweden)

    Osmir Cabrera-Blanco

    2017-04-01

    Full Text Available Las autoridades regulatorias recomiendan el uso de técnicas de Resonancia Magnética Nuclear o técnicas serológicas para la determinación de la identidad de los antígenos presentes en las vacunas conjugadas. Con la aparición de las vacunas conjugadas multivalentes, se ha hecho necesario recurrir a técnicas inmunoquímicas con la utilización de anticuerpos monoclonales para aumentar la sensibilidad en la determinación de la identidad de los antígenos en dichas vacunas conjugadas. El objetivo del presente trabajo fue establecer las condiciones óptimas de trabajo que permitieran utilizar la técnica del Dot Blot para determinar la identidad de los antígenos en vacunas conjugadas de Streptococcus pneumoniae serotipo 19F. Para ello se estudiaron los tiempos de incubación, la influencia del reactivo en la solución de bloqueo; también las concentraciones óptimas del anticuerpo monoclonal y de los ingredientes farmacéuticos activos, así como los volúmenes de aplicación óptimos para estos y vacunas. Se utilizó un anticuerpo monoclonal contra el polisacárido capsular del serotipo 19F de neumococo. Las muestras empleadas en este trabajo fueron lotes de ingredientes farmacéuticos activos de conjugados de polisacárido capsular 19F y lotes de un candidato vacunal cubano conjugado heptavalente contra neumococos. Los resultados mostraron que para la determinación de la identidad antigénica fueron suficientes 10 µL de muestras de los principios activos a una concentración de 125 µg/mL e igual volumen para las vacunas heptavalentes. Quedó demostrado que una concentración de 1 µg/mL para el anticuerpo monoclonal y tiempos de incubación de 30 min a 37 °C fueron suficientes para la determinación. Estos resultados permiten concluir que quedaron establecidas las condiciones óptimas de trabajo para determinar la identidad antigénica por Dot Blot del polisacárido capsular de S. pneumoniae serotipo 19F presente en las vacunas

  20. Unusual monosaccharides: components of O-antigenic polysaccharides of microorganisms

    Science.gov (United States)

    Kochetkov, Nikolai K.

    1996-09-01

    The data on new monosaccharides detected in O-antigenic polysaccharides of Gram-negative bacteria have been surveyed. The results of isolation and structure determination of these unusual monosaccharides have been arranged and described systematically. The NMR spectroscopy techniques are shown to be promising for the O-antigenic polysaccharides structure determination. The information about fine structure of monosaccharides which constitute the base of important class of microbial polysaccharides, is of great significance for applied studies, first of all, the design and synthesis of biologically active substances. The bibliography includes 216 references.

  1. Serotyping and Antibiotic Susceptibility Pattern of Common Bacterial Uropathogens in Urinary Tract Infections in Koohdasht, Lorestan Province

    Directory of Open Access Journals (Sweden)

    Siavash Amraei

    2016-05-01

    Full Text Available Background: Oneof themostcommondiseases worldwide is urinary tract infection (UTI. The main agents causing these infectionsare bacteria. Urinary tract infections occur when uropathogens colonize the urethra, migrate to the bladder and invade urinary tract cells. Objectives: The purpose of this study was the detection of uropathogens causing UTIs, as well as serotyping and antibiotic susceptibility of the most common bacteria. Materials and Methods: The study was performed on 300 urine samples collected from patients referred to Koohdasht Imam Khomeini hospital of Lorestan province. After culturing the samples and determination of uropathogens, antibiotic susceptibility test was performed by the Kirby-Bauer disk diffusion method. Serotyping was performed for the most common uropathogens by polyvalent and monovalent antisera. Results: Of the 300 samples, 61 samples (20.33% were positive for UTIs. Among these, 49 samples (80.33% were Gram-negative bacteria and 12 (19.67% Gram-positive. The most common uropathogens in UTIs were Escherichia coli (55.74%, Proteus species (11.47%, Staphylococcus epidermidis (11.47%, Citrobacter species (8.20%, Staphylococcus aureus (8.20% and Klebsiella species (4.92%, respectively. The rate of UTI in females (83.61% was more than males (16.39%. The highest level of resistance was towards trimethoprim/sulfamethoxazole and the lowest to ampicillin, ciprofloxacin and nitrofurantoin. The most common uropathogen was Escherichia coli and the most common serotypes were O142:K86 and O25:K11, respectively. Conclusions: The treatment of UTIs and resistance control in bacteria should be done based on common strains and choosing an effective antibiotic. Therefore, the determination of prevalent bacterial strains in UTIs of each region based on laboratory tests is very important.

  2. Biodegradation of bacterial polysaccharides adsorbed on montmorillonite

    International Nuclear Information System (INIS)

    Guckert, A.; Tok, H.H.; Jacquin, F.

    1977-01-01

    In this research, by means of a model, a study was made of the biodegradation of microbial organic compounds adsorbed on clays, with a parallel experiment on Fontainebleau sand serving as the control. During incubation the three classes of organic matter ( 14 C-labelled glucose, 14 C-labelled polysaccharides and 14 C-labelled microbial cells) mineralize more actively in the presence of sand than in the presence of clay, since the latter provides protection against biodegradation. Mineralization of the adsorbed organic compounds, however, is marked by clear-cut differences after three weeks - glucose (55%)>polysaccharides (43%)>microbial organisms (7.3%). After incubation, chemical extraction of the organo-mineral complexes by alkaline solvents shows only water-soluble and alkali-soluble products in the case of sand; conversely, in that of montmorillonite the bulk of the 14 C was found in the non-extractable fraction or humin (18.1% of the initial 14 C for glucose, 27.3% for the polysaccharides, and 67.6% for the microbial organisms). A second incubation carried out after a phase in which there was drying and remoistening of the organo-mineral complexes, brings to light the important part played by climatic alternations during the biodegradation process. A new mineralization phase is observed, affecting more the bacterial organisms (14.1%) than the polysaccharides (6.3%), with the glucose-base complexes occupying an intermediate position (11.2%). The chemical fractioning of the organo-mineral complexes following re-incubation shows the stability of 14 C in humin very clearly, especially in the case of polysaccharides, where the mineralization phase relates primarily to the products extractable with alkalis. (author)

  3. [Variation of polysaccharides and alcohol-soluble extracts content of Dendrobium officinale].

    Science.gov (United States)

    Yu, Qiao-xian; Guo, Ying-ying; Si, Jin-ping; Wu, Ling-shang; Wang, Lin-hua

    2014-12-01

    To reveal the variation of polysaccharides and alcohol-soluble extract contents of Dendrobium officinale, the polysaccharides and alcohol-soluble extracts contents of three D. officinale strains were determined by phenol-sulfuric acid method and hot-dip method, respectively. The results showed that the contents of polysaccharides and alcohol-soluble extracts and their total content were significantly different among D. officinale samples collected in different periods, and the variations were closely related to the phenology of D. officinale. Additionally, the quality variation of polysaccharides was closely related to the flowering of D. officinale, while the alcohol-soluble extracts was closely associated to the formation and germination of buds. According to the dynamic variation of these two compounds, it is more reasonable to harvest D. officinale at biennials pre-bloom than at specific harvesting month considering polysaccharides content. It is better to harvest before the germination of buds considering alcohol-soluble extracts. While with regards to both polysaccharides and alcohol-soluble extract, it is better to harvest this plant at the period from the sprouting to pre-bloom next year.

  4. Molecular typing, antibiotic resistance, virulence gene and biofilm formation of different Salmonella enterica serotypes.

    Science.gov (United States)

    Turki, Yousra; Mehr, Ines; Ouzari, Hadda; Khessairi, Amel; Hassen, Abdennaceur

    2014-01-01

    Salmonella enterica isolates representing commonly isolated serotypes in Tunisia were analyzed using genotyping and phenotyping methods. ERIC and ITS-PCR applied to 48 Salmonella spp. isolates revealed the presence of 12 and 10 different profiles, respectively. The distribution of profiles among serotypes demonstrated the presence of strains showing an identical fingerprinting pattern. All Salmonella strains used in this study were positive for the sdiA gene. Three Salmonella isolates belonging to serotypes Anatum, Enteritidis and Amsterdam were negative for the invA gene. The spvC gene was detected in thirteen isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Gallinarum and Montevideo. Antibiotic resistance was frequent among the recovered Salmonella isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Zanzibar and Derby. The majority of these isolates exhibited resistance to at least two antibiotic families. Four multidrug-resistant isolates were recovered from food animals and poultry products. These isolates exhibited not only resistance to tetracycline, sulphonamides, and ampicillin, but also have shown resistance to fluoroquinolones. Common resistance to nalidixic acid, ciprofloxacin and ofloxacin in two S. Anatum and S. Zanzibar strains isolated from raw meat and poultry was also obtained. Furthermore, wastewater and human isolates exhibited frequent resistance to nalidixic acid and tetracycline. Of all isolates, 33.5% were able to form biofilm.

  5. Phenotypic and molecular characterization of Salmonella serotypes ...

    African Journals Online (AJOL)

    The presence of Salmonella and human pathogens in unpasteurized milk remains a public health hazard. The study reported the phenotypic and molecular characterization of Salmonella serotypes in cow raw milk, cheese and traditional yoghurt marketed for man's consumption in Nigeria. Isolation of Salmonella was done ...

  6. DFT-GIAO calculation of properties of {sup 19}F NMR and stability study of environmentally relevant perfluoroalkylsulfonamides (PFASAmide)

    Energy Technology Data Exchange (ETDEWEB)

    Mejia-Urueta, Rafael; Mestre-Quintero, Kleyber; Vivas-Reyes, Ricardo, E-mail: rvivasr@unicartagena.edu.co [Grupo de Quimica Cuantica y Teorica, Facultad de Ciencias Exactas y Naturales, Universidad de Cartagena, Cartagena (Colombia)

    2011-09-15

    Perfluorinated organic compounds (POCs), such as perfluorooctanesulfonate (PFOS) and perfluoroalkylsulfonamide (PFASA) are compounds that have recently attracted considerable attention worldwide because of its high persistence and wide distribution in the environment. Among the spectroscopic methods used to study the PFASA, {sup 19}F nuclear magnetic resonance (NMR {sup 19}F) is very effective, due to its ability to determine concentrations of PFASA in biological samples and measure pollution in water samples. For this reason, a theoretical study of the properties of {sup 19}F NMR was performed. In this study we have determined the shielding constant ({sigma}) for different fluorine nucleus of the 18 molecules under study, using density functional theory (DFT) and GIAO method with the B3PW91/6-31+G(d,p) level of calculation. The {sigma} calculations were made at vacuum and in presence of a solvent. The values of chemical shifts ({delta}), were also calculated in a different level of theory. The best results were obtained with the level of calculation DFT-GIAO/B3PW91/6-31+G(d,p) by considering the solvent such as dimethylsulfoxide (DMSO), chloroform (CHCl{sub 3}), acetone (CH{sub 3}COCH{sub 3}) and methanol (CH{sup 3}OH). The results were interpreted in terms of calculated hardness at DFT/B3PW91/6-31+G(d, p) level. The behaviour of the hardness was higher in the molecules of four carbons PFASA than eight carbons. This explain theoretically resistance of four carbons PFAS to be transformed into perfluorobutanesulfonate (PFBS). (author)

  7. Salmonella serotypes and their antimicrobial susceptibility in apparently healthy dogs in Addis Ababa, Ethiopia.

    Science.gov (United States)

    Kiflu, Bitsu; Alemayehu, Haile; Abdurahaman, Mukarim; Negash, Yohannes; Eguale, Tadesse

    2017-05-19

    The close bond between pet animals and family members poses risk of infection with zoonotic bacterial pathogens such as Salmonella. No data is available on occurrence of Salmonella in dogs in Ethiopia. The aim of this study was therefore to determine the prevalence, serotype distribution and antimicrobial resistance of Salmonella from feces of apparently healthy dogs in Addis Ababa, Ethiopia. Of the total 360 dogs examined, 42 (11.7%; 95% Confidence limit of 8.5%-15.4%) were positive for Salmonella. Fourteen serotypes were detected and the predominant ones were S. Bronx (n = 7; 16.7%), S. Newport (n = 6; 14.3%), followed by S. Typhimurium, S. Indiana, S. Kentucky, S. Saintpaul and S. Virchow (n = 4; 9.5%) each. Salmonella infection status was significantly associated with history of symptom of diarrhea during the past 60 days (OR = 3.78; CI = 1.76-8.13; p = 0). Highest resistance rates were found for oxytetracycline (59.5%), neomycin (50%), streptomycin (38.1%), cephalothin (33.3%), doxycycline (30.9%), ampicillin (30.9%) and amoxicillin + clavulanic acid (26.2%). Thirty eight (90.5%) of the isolates were resistant or intermediately resistant to at least one of the 16 antimicrobials tested. Resistance to two or more antimicrobials was detected in 30 (71.4%) of the isolates. Resistance to three or more antimicrobials was detected in 19 (45.2%) of the isolates. This study demonstrated high carriage rate of Salmonella serotypes known for causing human salmonellosis and large proportion of them were resistant to antimicrobials used in public and veterinary medicine for management of various bacterial infections, suggesting the possible risk of infection of human population in close contact with these dogs by drug resistant pathogens. Therefore, it is vital to work on raising public awareness on zoonotic canine diseases prevention measures and good hygienic practices.

  8. In vitro Antioxidant of a Water-Soluble Polysaccharide from Dendrobium fimhriatum Hook.var.oculatum Hook

    Science.gov (United States)

    Luo, Aoxue; Fan, Yijun

    2011-01-01

    A water-soluble crude polysaccharide (DFHP) obtained from the aqueous extracts of the stem of Dendrobium fimhriatum Hook.var.oculatum Hook through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 209.3 kDa. Monosaccharide analysis revealed that DFHP was composed of mannose, glucose and galactose in a content ratio of 37.52%; 43.16%; 19.32%. The investigation of antioxidant activity in vitro showed that DFHP is a potential antioxidant. PMID:21747725

  9. Shift in serotype distribution of Shigella species in China, 2003-2013.

    Science.gov (United States)

    Qiu, S; Xu, X; Yang, C; Wang, J; Liang, B; Li, P; Li, H; Yi, S; Liu, H; Cui, X; Wu, Z; Xie, J; Jia, L; Wang, L; Hao, R; Jin, H; Wang, Y; Sun, Y; Song, H

    2015-03-01

    We identified 2912 Shigella isolates from diarrhoeal patients in China during 2003-2013. The most common species was Shigella flexneri (55.3%), followed by Shigella sonnei (44.1%); however, S. sonnei is becoming increasingly prevalent. Among the S. flexneri isolates, serotypes 2a and X variant (-:7,8, E1037) were the two most prevalent serotypes, and serologically atypical isolates were also commonly identified. Overall, S. sonnei, S. flexneri 2a and S. flexneri X variant (-:7,8, E1037) accounted for 76.1% of all Shigella isolates, and their prevalence increased from 54.0% during 2003-2004 to 84.1% during 2011-2013. A change was observed in the serotype distribution of Shigella in China during this period, and we propose an ideal strategy to inform the development of a broadly effective Shigella vaccine candidate. Copyright © 2014 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  10. Characterization of Streptococcus suis through serotyping, SE-AFLP and virulence profile

    Directory of Open Access Journals (Sweden)

    Franco F. Calderaro

    Full Text Available Abstract: Streptococcus suis is one of most important pathogens in the swine industry worldwide. Despite its importance, studies of S. suis characterization in South America are still rare. This study evaluates S. suis isolates from distinct Brazilian states, from 1999 to 2004, and its molecular and serological characterization. A total of 174 isolates were studied. S. suis identification was confirmed by PCR and isolates were further serotyped and genotyped by SE-AFLP and amplification of virulence markers. Serotype 1, 2, 3, 4, 7, 18, 22 and 32 were identified among the studied isolates, and only 4% were characterized as non-typeable. The mrp+/epf+/sly+ genotype was the most frequent. The SE-AFLP analysis resulted in 29 patterns distributed in three main clusters with over 65% of genetic similarity. Isolates presented a slight tendency to cluster according to serotype and origin; however, no further correlation with virulence genotypes was observed.

  11. Structural studies of the O-specific polysaccharide(s) from the lipopolysaccharide of Azospirillum brasilense type strain Sp7.

    Science.gov (United States)

    Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

    2013-10-18

    Lipopolysaccharide was obtained by phenol-water extraction from dried bacterial cells of Azospirillum brasilense type strain Sp7. Mild acid hydrolysis of the lipopolysaccharide followed by GPC on Sephadex G-50 resulted in a polysaccharide mixture, which was studied by composition and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy. The following polysaccharide structures were established, where italics indicate a non-stoichiometric (∼40%) 2-O-methylation of l-rhamnose. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Pistachio hull water-soluble polysaccharides as a novel prebiotic agent.

    Science.gov (United States)

    Akbari-Alavijeh, Safoura; Soleimanian-Zad, Sabihe; Sheikh-Zeinoddin, Mahmoud; Hashmi, Sarwar

    2018-02-01

    We isolated and characterized pistachio hull polysaccharides (PHP). The PHP was a heteropolysaccharide mainly contained 75.50% (w/w) total sugar and 9.51% (w/w) uronic acid. As determined by GPC analysis, the polysaccharide with a molecular weight of 3.71×10 6 D (83.2%) was the most dominant fraction. Moreover, HPLC analysis indicated that PHP was predominantly composed of xylose, glucose, arabinose, and fructose with a molar ratio of 1.00:2.50:19.67:28.81. FT-IR and NMR analysis also confirmed the results obtained by HPLC and characterized preliminary structure features of the PHP. Functional properties of the PHP including water holding capacity (WHC: 2.44±0.05g water/g DM), and oil holding capacity (OHC: 11.53±0.04g oil/g DM) were significant compared to inulin used as reference prebiotic (pPHP remained 94.37% undigested in the simulated digestion process and stimulated the growth of L. plantarum PTCC 1896 and L. rhamnosus GG and increased the acetate, propionate and butyrate production over inulin in vitro. Totally, the PHP showed a considerable prebiotic capability and high WHC, OHC suggesting that the PHP is a potent pharmaceutical with good technological properties which can be used in food and drug industries. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Matrix polyelectrolyte capsules based on polysaccharide/MnCO₃ hybrid microparticle templates.

    Science.gov (United States)

    Wei, Qingrong; Ai, Hua; Gu, Zhongwei

    2011-06-15

    An efficient strategy for biomacromolecule encapsulation based on spontaneous deposition into polysaccharide matrix-containing capsules is introduced in this study. First, hybrid microparticles composed of manganese carbonate and ionic polysaccharides including sodium hyaluronate (HA), sodium alginate (SA) and dextran sulfate sodium (DS) with narrow size distribution were synthesized to provide monodisperse templates. Incorporation of polysaccharide into the hybrid templates was successful as verified by thermogravimetric analysis (TGA) and confocal laser scanning microscopy (CLSM). Matrix polyelectrolyte microcapsules were fabricated through layer-by-layer (LbL) self-assembly of oppositely charged polyelectrolytes (PEs) onto the hybrid particles, followed by removal of the inorganic part of the cores, leaving polysaccharide matrix inside the capsules. The loading and release properties of the matrix microcapsules were investigated using myoglobin as a model biomacromolecule. Compared to matrix-free capsules, the matrix capsules had a much higher loading capacity up to four times; the driving force is mostly due to electrostatic interactions between myoglobin and the polysaccharide matrix. From our observations, for the same kind of polysaccharide, a higher amount of polysaccharide inside the capsules usually led to better loading capacity. The release behavior of the loaded myoglobin could be readily controlled by altering the environmental pH. These matrix microcapsules may be used as efficient delivery systems for various charged water-soluble macromolecules with applications in biomedical fields. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. The Effect of Intermolecular Halogen Bond on 19F DNP Enhancement in 1, 4-Diiodotetrafluorobenzene/4-OH-TEMPO Supramolecular Assembly

    Directory of Open Access Journals (Sweden)

    GAO Shan

    2017-12-01

    Full Text Available Halogen bond, as hydrogen bond, is a non-covalent bond. Dynamic nuclear polarization (DNP technique has been used previously to study hydrogen bonds-mediated intermolecular interactions. However, no study has been carried out so far to study the halogen bond-mediated intermolecular interactions with DNP. In this work, 19F DNP polarization efficiency of the halogen bonds existing in supramolecular assembling by 4-OH-TEMPO and 1,4-diiodotetrafluorobenzene (DITFB was studied on a home-made DNP system. The formation of intermolecular halogen bonds appeared to increase 19F DNP polarization efficiency, suggesting that the spin-spin interactions among electrons were weakened by the halogen bonds, resulting in an increased T2e and a larger saturation factor.

  15. Development and Evaluation of a Rapid Antigen Detection and Serotyping Lateral Flow Antigen Detection System for Foot-and-Mouth Disease Virus.

    Directory of Open Access Journals (Sweden)

    Kazuki Morioka

    Full Text Available We developed a lateral flow strip using monoclonal antibodies (MAbs which allows for rapid antigen detection and serotyping of foot-and-mouth disease virus (FMDV. This FMDV serotyping strip was able to detect all 7 serotypes and distinguish serotypes O, A, C and Asia1. Its sensitivities ranged from 10(3 to 10(4 of a 50% tissue culture infectious dose of each FMDV stain; this is equal to those of the commercial product Svanodip (Boehringer Ingelheim Svanova, Uppsala, Sweden, which can detect all seven serotypes of FMDV, but does not distinguish them. Our evaluation of the FMDV serotyping strip using a total of 118 clinical samples (vesicular fluids, vesicular epithelial emulsions and oral and/or nasal swabs showed highly sensitive antigen detection and accuracy in serotyping in accordance with ELISA or RT-PCR. To the best of our knowledge, this is the first report on any FMDV serotyping strip that provides both rapid antigen detection and serotyping of FMDV at the same time on one strip without extra devices. This method will be useful in both FMD-free countries and FMD-infected countries, especially where laboratory diagnosis cannot be carried out.

  16. Virulence, serotype and phylogenetic groups of diarrhoeagenic ...

    African Journals Online (AJOL)

    Dr DADIE Thomas

    2014-02-17

    Feb 17, 2014 ... The virulence, serotype and phylogenetic traits of diarrhoeagenic Escherichia coli were detected in 502 strains isolated during digestive infections. Molecular detection of the target virulence genes, rfb gene of operon O and phylogenetic grouping genes Chua, yjaA and TSPE4.C2 was performed.

  17. Chlamydia trachomatis serotype A infections in the Amazon region of Brazil: prevalence, entry and dissemination

    Directory of Open Access Journals (Sweden)

    Marluísa de Oliveira Guimarães Ishak

    2015-04-01

    Full Text Available INTRODUCTION: Chlamydia infection is associated with debilitating human diseases including trachoma, pneumonia, coronary heart disease and urogenital diseases. Serotypes of C. trachomatis show a fair correlation with the group of diseases they cause, and their distribution follows a well-described geographic pattern. Serotype A, a trachoma-associated strain, is known for its limited dissemination in the Middle East and Northern Africa. However, knowledge on the spread of bacteria from the genus Chlamydia as well as the distribution of serotypes in Brazil is quite limited. METHODS: Blood samples of 1,710 individuals from ten human population groups in the Amazon region of Brazil were examined for antibodies to Chlamydia using indirect immunofluorescence and microimmunofluorescence assays. RESULTS: The prevalence of antibodies to Chlamydia ranged from 23.9% (Wayana-Apalai to 90.7% (Awa-Guaja with a mean prevalence of 50.2%. Seroreactivity was detected to C. pneumoniae and to all serotypes of C. trachomatis tested; furthermore, we report clear evidence of the as-yet-undescribed occurrence of serotype A of C. trachomatis. CONCLUSIONS: Specific seroreactivity not only accounts for the large extent of dissemination of C. trachomatis in the Amazon region of Brazil but also shows an expanded area of occurrence of serotype A outside the epidemiological settings previously described. Furthermore, these data suggest possible routes of Chlamydia introduction into the Amazon region from the massive human migration that occurred during the 1,700s.

  18. New polysaccharide-based polymer electrolytes; Nouveaux electrolytes polymeres a base de polysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Velasquez-Morales, P.; Le Nest, J.F.; Gandini, A. [Ecole Francaise de Papeterie et des Industries Graphique, 38 - Saint Martin d`Heres (France)

    1996-12-31

    Polysaccharides like cellulose and chitosan are known for their filmic properties. This paper concerns the synthesis and the study of chitosan-based polymer electrolytes. A preliminary work concerns the study of glucosamine reactivity. The poly-condensation of chitosan ethers (obtained by reaction with ethylene oxide or propylene oxide) with bifunctional and monofunctional oligo-ethers leads to the formation of thin lattices (10 {mu}m) having excellent mechanical properties. The presence of grafted polyether chains along the polysaccharide skeleton allows to modify the vitreous transition temperature and the molecular disorder of the system. Two type of polymer electrolytes have been synthesized: electrolytes carrying a dissolved alkaline metal salt and ionomers. The analysis of their thermal, dynamical mechanical, nuclear magnetic relaxation, electrical, and electrochemical properties shows that this new class of polymer electrolytes has the same performances as ethylene poly-oxide based amorphous lattices plus the advantage of having good filmic properties. Abstract only. (J.S.)

  19. New polysaccharide-based polymer electrolytes; Nouveaux electrolytes polymeres a base de polysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Velasquez-Morales, P; Le Nest, J F; Gandini, A [Ecole Francaise de Papeterie et des Industries Graphique, 38 - Saint Martin d` Heres (France)

    1997-12-31

    Polysaccharides like cellulose and chitosan are known for their filmic properties. This paper concerns the synthesis and the study of chitosan-based polymer electrolytes. A preliminary work concerns the study of glucosamine reactivity. The poly-condensation of chitosan ethers (obtained by reaction with ethylene oxide or propylene oxide) with bifunctional and monofunctional oligo-ethers leads to the formation of thin lattices (10 {mu}m) having excellent mechanical properties. The presence of grafted polyether chains along the polysaccharide skeleton allows to modify the vitreous transition temperature and the molecular disorder of the system. Two type of polymer electrolytes have been synthesized: electrolytes carrying a dissolved alkaline metal salt and ionomers. The analysis of their thermal, dynamical mechanical, nuclear magnetic relaxation, electrical, and electrochemical properties shows that this new class of polymer electrolytes has the same performances as ethylene poly-oxide based amorphous lattices plus the advantage of having good filmic properties. Abstract only. (J.S.)

  20. Evaluation of recurrent disease in the re-staging of colorectal cancer by 18F-FDG PET/CT: Use of CEA and CA 19-9 in patient selection.

    Science.gov (United States)

    Chiaravalloti, Agostino; Fiorentini, Alessandro; Palombo, Erika; Rinino, Davide; Lacanfora, Annamaria; Danieli, Roberta; Di Russo, Carmen; Di Biagio, Daniele; Squillaci, Ettore; Schillaci, Orazio

    2016-11-01

    The aim of the present retrospective study was to evaluate the sensitivity and specificity of fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) in assessing the recurrence of colorectal cancer (CRC) with regard to carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA 19-9). 18 F-FDG PET/CT was performed in 100 patients for the re-staging of CRC. Therapy was discontinued prior to the examination. The mean (± standard deviation) CEA value (measured ~30 days prior to PET/CT examination) was 23.71 (±107) ng/ml, whereas the CA 19-9 value was 72 (±190.3) U/ml. Differences in CEA and CA 19-9 values in patients with scans that were positive or negative for recurrence were analyzed by means of a receiver operating characteristic (ROC) curve. ROC curves were used for the calculation of the sensitivity and specificity of 18 F-FDG PET/CT for the CEA and CA 19-9 levels. The results of the 18 F-FDG PET/CT were found to be associated with the CEA level (P=0.001), but not with the CA 19-9 level (P=0.43). PET/CT was positive for recurrence in 60 patients (60.0%), whose mean CEA and CA 19-9 values were 33.07±136.7 ng/ml and 75.24±192.3 U/ml, respectively. PET/CT was negative for recurrence in 40 patients (40.0%), whose mean CEA and CA 19-9 values were 10.15±30 ng/ml and 67.76±190 U/ml, respectively. On the basis of ROC curve analysis, the best compromise between sensitivity and specificity was achieved for CEA levels of 3.5 ng/ml [sensitivity, 80%; 95% confidence interval (CI), 67-89%; and specificity, 60%; 95% CI, 45-78%]. The study concluded that the detection of recurrence by 18 F-FDG PET/CT in patients treated for CRC is associated with CEA, but not CA 19-9 serum levels. Moreover, 18 F-FDG PET/CT should be recommended in patients with suspected CRC recurrence even when they present with CEA levels below the normal cut-off.

  1. Metabolism of 5-fluorouracil in human liver: an in vivo 19F NMR study

    International Nuclear Information System (INIS)

    Mohankrishnan, P.; Sprigg, J.; Cardwell, D.; Komoroski, R.A.; Hutchins, L.; Nauke, S.; Williamson, M.R.; Jagannathan, N.R.

    1999-01-01

    In vivo fluorine-19 nuclear magnetic resonance ( 19 F NMR) spectroscopy was used to study the metabolism and pharmacokinetics of 5-fluorouracil (5-FU) in human liver. Nine patients received 5-FU, and additional chemotherapeutic agents (methotrexate, leucovorin, or levamisole) either prophylactically after breast cancer surgery or for colorectal cancer. The time constant for the disappearance of 5-FU from the liver in vivo varied from 5 to 17 min, while the time constant for the appearance of α-fluoro-β-alanine (the major catabolite of 5 FU) varied from 7 to 86 min. The modulators of 5-FU metabolism did not appear to affect the time constant for the disappearance of 5-FU from the liver or for the appearance of α-fluoro-β-alanine. Results obtained indicate that the pharmacokinetics of 5-FU and α-fluoro-β-alanine may vary substantially at different times in a given individual. (author)

  2. A comparison of chemical shift sensitivity of trifluoromethyl tags: optimizing resolution in {sup 19}F NMR studies of proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Libin; Larda, Sacha Thierry; Frank Li, Yi Feng [University of Toronto, UTM, Department of Chemistry (Canada); Manglik, Aashish [Stanford University School of Medicine, Department of Molecular and Cellular Physiology (United States); Prosser, R. Scott, E-mail: scott.prosser@utoronto.ca [University of Toronto, UTM, Department of Chemistry (Canada)

    2015-05-15

    The elucidation of distinct protein conformers or states by fluorine ({sup 19}F) NMR requires fluorinated moieties whose chemical shifts are most sensitive to subtle changes in the local dielectric and magnetic shielding environment. In this study we evaluate the effective chemical shift dispersion of a number of thiol-reactive trifluoromethyl probes [i.e. 2-bromo-N-(4-(trifluoromethyl)phenyl)acetamide (BTFMA), N-(4-bromo-3-(trifluoromethyl)phenyl)acetamide (3-BTFMA), 3-bromo-1,1,1-trifluoropropan-2-ol (BTFP), 1-bromo-3,3,4,4,4-pentafluorobutan-2-one (BPFB), 3-bromo-1,1,1-trifluoropropan-2-one (BTFA), and 2,2,2-trifluoroethyl-1-thiol (TFET)] under conditions of varying polarity. In considering the sensitivity of the {sup 19}F NMR chemical shift to the local environment, a series of methanol/water mixtures were prepared, ranging from relatively non-polar (MeOH:H{sub 2}O = 4) to polar (MeOH:H{sub 2}O = 0.25). {sup 19}F NMR spectra of the tripeptide, glutathione ((2S)-2-amino-4-{[(1R)-1-[(carboxymethyl)carbamoyl] -2-sulfanylethyl]carbamoyl}butanoic acid), conjugated to each of the above trifluoromethyl probes, revealed that the BTFMA tag exhibited a significantly greater range of chemical shift as a function of solvent polarity than did either BTFA or TFET. DFT calculations using the B3LYP hybrid functional and the 6-31G(d,p) basis set, confirmed the observed trend in chemical shift dispersion with solvent polarity.

  3. Optimization of localized 19F magnetic resonance spectroscopy for the detection of fluorinated drugs in the human liver.

    NARCIS (Netherlands)

    Klomp, D.W.J.; Laarhoven, H.W.M. van; Kentgens, A.P.M.; Heerschap, A.

    2003-01-01

    Fluorine MR spectroscopy ((19)F MRS) is an indispensable tool for assessing the pharmacokinetics of fluorinated drugs. Since the metabolism of 5-fluorouracil (5FU), a frequently used cytotoxic drug, is expected to be different in normal liver and in tumor tissue, spatial localization is required for

  4. Optimization of localized 19F magnetic resonance spectroscopy for the detection of fluorinated drugs in the human liver

    NARCIS (Netherlands)

    Klomp, Dennis W. J.; van Laarhoven, Hanneke W. M.; Kentgens, Arno P. M.; Heerschap, Arend

    2003-01-01

    Fluorine MR spectroscopy ((19)F MRS) is an indispensable tool for assessing the pharmacokinetics of fluorinated drugs. Since the metabolism of 5-fluorouracil (5FU), a frequently used cytotoxic drug, is expected to be different in normal liver and in tumor tissue, spatial localization is required for

  5. Immunogold scanning electron microscopy can reveal the polysaccharide architecture of xylem cell walls

    Science.gov (United States)

    Sun, Yuliang; Juzenas, Kevin

    2017-01-01

    Abstract Immunofluorescence microscopy (IFM) and immunogold transmission electron microscopy (TEM) are the two main techniques commonly used to detect polysaccharides in plant cell walls. Both are important in localizing cell wall polysaccharides, but both have major limitations, such as low resolution in IFM and restricted sample size for immunogold TEM. In this study, we have developed a robust technique that combines immunocytochemistry with scanning electron microscopy (SEM) to study cell wall polysaccharide architecture in xylem cells at high resolution over large areas of sample. Using multiple cell wall monoclonal antibodies (mAbs), this immunogold SEM technique reliably localized groups of hemicellulosic and pectic polysaccharides in the cell walls of five different xylem structures (vessel elements, fibers, axial and ray parenchyma cells, and tyloses). This demonstrates its important advantages over the other two methods for studying cell wall polysaccharide composition and distribution in these structures. In addition, it can show the three-dimensional distribution of a polysaccharide group in the vessel lateral wall and the polysaccharide components in the cell wall of developing tyloses. This technique, therefore, should be valuable for understanding the cell wall polysaccharide composition, architecture and functions of diverse cell types. PMID:28398585

  6. O-sulfated bacterial polysaccharides with low anticoagulant activity inhibit metastasis.

    Science.gov (United States)

    Borgenström, Marjut; Wärri, Anni; Hiilesvuo, Katri; Käkönen, Rami; Käkönen, Sanna; Nissinen, Liisa; Pihlavisto, Marjo; Marjamäki, Anne; Vlodavsky, Israel; Naggi, Annamaria; Torri, Giangiacomo; Casu, Benito; Veromaa, Timo; Salmivirta, Markku; Elenius, Klaus

    2007-07-01

    Heparin-like polysaccharides possess the capacity to inhibit cancer cell proliferation, angiogenesis, heparanase-mediated cancer cell invasion, and cancer cell adhesion to vascular endothelia via adhesion receptors, such as selectins. The clinical applicability of the antitumor effect of such polysaccharides, however, is compromised by their anticoagulant activity. We have compared the potential of chemically O-sulfated and N,O-sulfated bacterial polysaccharide (capsular polysaccharide from E. COLI K5 [K5PS]) species to inhibit metastasis of mouse B16-BL6 melanoma cells and human MDA-MB-231 breast cancer cells in two in vivo models. We demonstrate that in both settings, O-sulfated K5PS was a potent inhibitor of metastasis. Reducing the molecular weight of the polysaccharide, however, resulted in lower antimetastatic capacity. Furthermore, we show that O-sulfated K5PS efficiently inhibited the invasion of B16-BL6 cells through Matrigel and also inhibited the in vitro activity of heparanase. Moreover, treatment with O-sulfated K5PS lowered the ability of B16-BL6 cells to adhere to endothelial cells, intercellular adhesion molecule-1, and P-selectin, but not to E-selectin. Importantly, O-sulfated K5PSs were largely devoid of anticoagulant activity. These findings indicate that O-sulfated K5PS polysaccharide should be considered as a potential antimetastatic agent.

  7. Comparative profiling of the transcriptional response to iron restriction in six serotypes of Actinobacillus pleuropneumoniae with different virulence potential

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    Angen Øystein

    2010-12-01

    Full Text Available Abstract Background Comparative analysis of gene expression among serotypes within a species can provide valuable information on important differences between related genomes. For the pig lung pathogen Actinobacillus pleuropneumoniae, 15 serotypes with a considerable variation in virulence potential and immunogenicity have been identified. This serotypic diversity can only partly be explained by amount of capsule and differences in the RTX toxin genes in their genomes. Iron acquisition in vivo is an important bacterial function and in pathogenic bacteria, iron-limitation is often a signal for the induction of virulence genes. We used a pan-genomic microarray to study the transcriptional response to iron restriction in vitro in six serotypes of A. pleuropneumoniae (1, 2, 3, 5b, 6, and 7, representing at least two levels of virulence. Results In total, 45 genes were significantly (p A. pleuropneumoniae was the up-regulation of a putative cirA-like siderophore in all six serotypes. Three genes, recently described in A. pleuropneumoniae as possibly coding for haemoglobin-haptoglobin binding proteins, displayed significant serotype related up-regulation to iron limitation. For all three genes, the expression appeared at its lowest in serotype 3, which is generally considered one of the least virulent serotypes of A. pleuropneumoniae. The three genes share homology with the hmbR haemoglobin receptor of Neisseria meningitidis, a possible virulence factor which contributes to bacterial survival in rats. Conclusions By comparative analysis of gene expression among 6 different serotypes of A. pleuropneumoniae we identified a common set of presumably essential core genes, involved in iron regulation. The results support and expand previous observations concerning the identification of new potential iron acquisition systems in A. pleuropneumoniae, showing that this bacterium has evolved several strategies for scavenging the limited iron resources of the

  8. Optimization of polysaccharides extraction from watermelon rinds: Structure, functional and biological activities.

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    Romdhane, Molka Ben; Haddar, Anissa; Ghazala, Imen; Jeddou, Khawla Ben; Helbert, Claire Boisset; Ellouz-Chaabouni, Semia

    2017-02-01

    In the present work, optimization of hot water extraction, structural characteristics, functional properties, and biological activities of polysaccharides extracted from watermelon rinds (WMRP) were investigated. The physicochemical characteristics and the monosaccharide composition of these polysaccharides were then determined using chemical composition analysis, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and gas chromatography-flame ionization detection (GC-FID). SEM images showed that extracted polysaccharides had a rough surface with many cavities. GC-FID results proved that galactose was the dominant sugar in the extracted polysaccharides, followed by arabinose, glucose, galacturonic acid, rhamnose, mannose, xylose and traces of glucuronic acid. The findings revealed that WMRP displayed excellent antihypertensive and antioxidant activities. Those polysaccharides had also a protection effect against hydroxyl radical-induced DNA damage. Functional properties of extracted polysaccharides were also evaluated. WMRP showed good interfacial dose-dependent proprieties. Overall, the results suggested that WMRP presents a promising natural source of antioxidants and antihypertensive agents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Plant cell wall polysaccharide analysis during cell elongation

    DEFF Research Database (Denmark)

    Guo, Xiaoyuan

    Plant cell walls are complex structures whose composition and architecture are important to various cellular activities. Plant cell elongation requires a high level of rearrangement of the cell wall polymers to enable cell expansion. However, the cell wall polysaccharides dynamics during plant cell...... elongation is poorly understood. This PhD project aims to elucidate the cell wall compositional and structural change during cell elongation by using Comprehensive Microarray Polymer Profiling (CoMPP), microscopic techniques and molecular modifications of cell wall polysaccharide. Developing cotton fibre......, pea and Arabidopsis thaliana were selected as research models to investigate different types of cell elongation, developmental elongation and tropism elongation. A set of comprehensive analysis covering 4 cotton species and 11 time points suggests that non-cellulosic polysaccharides contribute...

  10. Polysaccharides from Probiotics: New Developments as Food Additives

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    Philippe Michaud

    2010-01-01

    Full Text Available Microbial polysaccharides with nutraceutical potential and bioactive properties have been investigated in detail during the last few decades. There is an increasing demand in food industries for live microbes or polysaccharides produced by them which assert health benefits other than dietetic constituents. Although there are a large number of exopolysaccharide (EPS-producing bacteria, the titers are low for commercialization. This manuscript deals with the polysaccharides produced by probiotic strains, with major emphasis on the EPSs, their properties, applications and some of the strategies adopted which would be helpful in better understanding of the process in the near future. Research on the improved EPS biosynthesis is essential for obtaining high yields. Therefore, to reach commercialization, metabolic engineering must be applied.

  11. Antioxidant properties of cell wall polysaccharides of Stevia rebaudiana leaves

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    Mediesse Kengne Francine

    2014-12-01

    Full Text Available Objective: To examine the total phenolic and protein contents, and the antioxidant activities of cell wall polysaccharide fractions of Stevia rebaudiana leaves. Methods: Three different polysaccharide-enriched fractions, namely FPE (extract with 50 mmol/ L ethylene diamine tetra acetic acid, FPK (extract with 0.05 mol/L KOH and FH (extract with 4 mol/L KOH were extracted from Stevia rebaudiana leaves. The antioxidant activity of these fractions was evaluated based on their ability to scavenge DPPH (1, 1-diphenyl-2-picryl hydrazyl free radical, to reduce ferric power, to chelate ferrous ion and to protect human DNA. Results: The results indicated that protein content was found to be higher in FPK polysaccharide enriched fraction (47.48 µg per mg of FPK. Furthermore, the phenolic compound analysis according to the Folin-Ciocalteu method was higher in FPK (17.71 µg ferulic acid. The DPPH maximal inhibition percentage of the three polysaccharide-enriched fractions at 400 µg/mL was 27.66%, 59.90% and 23.21% respectively for FPE, FPK and FH. All the polysaccharide fractions exhibited a ferric reducing power except the FH one. The three fractions also exhibited lipid peroxidation inhibition, and they completely reverted the DNA damage induced by H2O2/FeCl2. FPK showed the strongest scavenging activity against the DPPH radical, the best chelating ability and lipid peroxidation inhibition. Conclusions: Stevia cell wall polysaccharide fractions are potent protective agents against oxidative stress. The analysis revealed major differences in the antioxidant activity in the three polysaccharides fractions. However, the 0.05 mol/L KOH pectin fraction (FPK showed better antioxidant activity.

  12. An adenovirus prime/plasmid boost strategy for induction of equipotent immune responses to two dengue virus serotypes.

    Science.gov (United States)

    Khanam, Saima; Rajendra, Pilankatta; Khanna, Navin; Swaminathan, Sathyamangalam

    2007-02-15

    Dengue is a public health problem of global significance for which there is neither an effective antiviral therapy nor a preventive vaccine. It is a mosquito-borne viral disease, caused by dengue (DEN) viruses, which are members of the Flaviviridae family. There are four closely related serotypes, DEN-1, DEN-2, DEN-3 and DEN-4, each of which is capable of causing disease. As immunity to any one serotype can potentially sensitize an individual to severe disease during exposure to a heterologous serotype, the general consensus is that an effective vaccine should be tetravalent, that is, it must be capable of affording protection against all four serotypes. The current strategy of creating tetravalent vaccine formulations by mixing together four monovalent live attenuated vaccine viruses has revealed the phenomenon of viral interference leading to the manifestation of immune responses biased towards a single serotype. This work stems from the emergence of (i) the DEN virus envelope (E) domain III (EDIII) as the most important region of the molecule from a vaccine perspective and (ii) the adenovirus (Ad) as a promising vaccine vector platform. We describe the construction of a recombinant, replication-defective Ad (rAd) vector encoding a chimeric antigen made of in-frame linked EDIIIs of DEN virus serotypes 2 and 4. Using this rAd vector, in conjunction with a plasmid vector encoding the same chimeric bivalent antigen, in a prime-boost strategy, we show that it is possible to elicit equipotent neutralizing and T cell responses specific to both DEN serotypes 2 and 4. Our data support the hypothesis that a DEN vaccine targeting more than one serotype may be based on a single DNA-based vector to circumvent viral interference. This work lays the foundation for developing a single Ad vector encoding EDIIIs of all four DEN serotypes to evoke a balanced immune response against each one of them. Thus, this work has implications for the development of safe and effective

  13. An adenovirus prime/plasmid boost strategy for induction of equipotent immune responses to two dengue virus serotypes

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    Swaminathan Sathyamangalam

    2007-02-01

    Full Text Available Abstract Background Dengue is a public health problem of global significance for which there is neither an effective antiviral therapy nor a preventive vaccine. It is a mosquito-borne viral disease, caused by dengue (DEN viruses, which are members of the Flaviviridae family. There are four closely related serotypes, DEN-1, DEN-2, DEN-3 and DEN-4, each of which is capable of causing disease. As immunity to any one serotype can potentially sensitize an individual to severe disease during exposure to a heterologous serotype, the general consensus is that an effective vaccine should be tetravalent, that is, it must be capable of affording protection against all four serotypes. The current strategy of creating tetravalent vaccine formulations by mixing together four monovalent live attenuated vaccine viruses has revealed the phenomenon of viral interference leading to the manifestation of immune responses biased towards a single serotype. Results This work stems from the emergence of (i the DEN virus envelope (E domain III (EDIII as the most important region of the molecule from a vaccine perspective and (ii the adenovirus (Ad as a promising vaccine vector platform. We describe the construction of a recombinant, replication-defective Ad (rAd vector encoding a chimeric antigen made of in-frame linked EDIIIs of DEN virus serotypes 2 and 4. Using this rAd vector, in conjunction with a plasmid vector encoding the same chimeric bivalent antigen, in a prime-boost strategy, we show that it is possible to elicit equipotent neutralizing and T cell responses specific to both DEN serotypes 2 and 4. Conclusion Our data support the hypothesis that a DEN vaccine targeting more than one serotype may be based on a single DNA-based vector to circumvent viral interference. This work lays the foundation for developing a single Ad vector encoding EDIIIs of all four DEN serotypes to evoke a balanced immune response against each one of them. Thus, this work has

  14. Antiviral Potential of Algae Polysaccharides Isolated from Marine Sources: A Review

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    Azin Ahmadi

    2015-01-01

    Full Text Available From food to fertilizer, algal derived products are largely employed in assorted industries, including agricultural, biomedical, food, and pharmaceutical industries. Among different chemical compositions isolated from algae, polysaccharides are the most well-established compounds, which were subjected to a variety of studies due to extensive bioactivities. Over the past few decades, the promising results for antiviral potential of algae-derived polysaccharides have advocated them as inordinate candidates for pharmaceutical research. Numerous studies have isolated various algal polysaccharides possessing antiviral activities, including carrageenan, alginate, fucan, laminaran, and naviculan. In addition, different mechanisms of action have been reported for these polysaccharides, such as inhibiting the binding or internalization of virus into the host cells or suppressing DNA replication and protein synthesis. This review strives for compiling previous antiviral studies of algae-derived polysaccharides and their mechanism of action towards their development as natural antiviral agents for future investigations.

  15. Co-circulation of two extremely divergent serotype SAT 2 lineages in Kenya highlights challenges to foot-and-mouth disease control

    DEFF Research Database (Denmark)

    Sangula, Abraham; Belsham, Graham; Muwanika, Vincent

    2010-01-01

    Amongst the SAT serotypes of foot-and-mouth disease virus (FMDV), the SAT 2 serotype is the most widely distributed throughout sub-Saharan Africa. Kenyan serotype SAT 2 viruses have been reported to display the highest genetic diversity for the serotype globally. This complicates diagnosis...... and control, and it is essential that patterns of virus circulation are known in order to overcome these difficulties. This study was undertaken to establish patterns of evolution of FMDV serotype SAT 2 in Kenya using complete VP1 coding sequences in a dataset of 65 sequences from Africa, collected over...

  16. Extraction, Structural Characterization, and Potential Antioxidant Activity of the Polysaccharides from Four Seaweeds

    Science.gov (United States)

    He, Jinzhe; Xu, Yaoyang; Chen, Hongbo; Sun, Peilong

    2016-01-01

    Four seaweed polysaccharides were extracted from Sarcodia ceylonensis, Ulva lactuca L., Gracilaria lemaneiformis, and Durvillaea antarctica, respectively, by microwave-assisted extraction. The effect of three significant variables (extraction time, extraction temperature, and the ratio of water to raw material) on the process for extracting polysaccharides was investigated, along with the optimization of the extraction using the response surface method (RSM) with a Box–Behnken design. The polysaccharide structure, monosaccharide composition, degree of sulfation, and molecular weight (MW) distribution were analyzed by infrared (IR) spectrometry, gas chromatography (GC), and high-performance gel permeation chromatography (HPGPC). IR spectrometry showed that Sarcodia ceylonensis polysaccharide (SCP), Ulva lactuca L. polysaccharide (ULLP), and Durvillaea antarctica polysaccharide (DAP) were all sulfated polysaccharides and, except Gracilaria lemaneiformis polysaccharide (GLP), all belong to β-pyranosidic polysaccharides. The average molecular weight (MW) of SCP, ULLP, GLP, and DAP was 466, 404, 591, and 482 kDa, respectively. The quantitative and comparative results with external standards indicated that the main monosaccharide in SCP and ULLP was mannose; and GLP and DAP were mainly composed of galactose and glucose, respectively. Then the in vitro antioxidant activity of all of the polysaccharides was evaluated using different assays—2,2–azino –bis (3-ethylbenzthiazoline-6- sulfonate) (ABTS), hydroxyl radical, nitrite scavenging capacity, and reducing power—and the relationship between their antioxidant activity and chemical characteristics were also examined. ULLP presented the highest ABTS radical scavenging activity; ULLP, SCP and DAP also showed a strong effect on the ABTS radical scavenging activity. SCP and ULLP exhibited excellent hydroxyl radical scavenging activities, about 83.33% ± 2.31% and 80.07% ± 2.17%, respectively, at 4 mg/mL. The

  17. Extraction, Structural Characterization, and Potential Antioxidant Activity of the Polysaccharides from Four Seaweeds

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    Jinzhe He

    2016-11-01

    Full Text Available Four seaweed polysaccharides were extracted from Sarcodia ceylonensis, Ulva lactuca L., Gracilaria lemaneiformis, and Durvillaea antarctica, respectively, by microwave-assisted extraction. The effect of three significant variables (extraction time, extraction temperature, and the ratio of water to raw material on the process for extracting polysaccharides was investigated, along with the optimization of the extraction using the response surface method (RSM with a Box–Behnken design. The polysaccharide structure, monosaccharide composition, degree of sulfation, and molecular weight (MW distribution were analyzed by infrared (IR spectrometry, gas chromatography (GC, and high-performance gel permeation chromatography (HPGPC. IR spectrometry showed that Sarcodia ceylonensis polysaccharide (SCP, Ulva lactuca L. polysaccharide (ULLP, and Durvillaea antarctica polysaccharide (DAP were all sulfated polysaccharides and, except Gracilaria lemaneiformis polysaccharide (GLP, all belong to β-pyranosidic polysaccharides. The average molecular weight (MW of SCP, ULLP, GLP, and DAP was 466, 404, 591, and 482 kDa, respectively. The quantitative and comparative results with external standards indicated that the main monosaccharide in SCP and ULLP was mannose; and GLP and DAP were mainly composed of galactose and glucose, respectively. Then the in vitro antioxidant activity of all of the polysaccharides was evaluated using different assays—2,2–azino –bis (3-ethylbenzthiazoline-6- sulfonate (ABTS, hydroxyl radical, nitrite scavenging capacity, and reducing power—and the relationship between their antioxidant activity and chemical characteristics were also examined. ULLP presented the highest ABTS radical scavenging activity; ULLP, SCP and DAP also showed a strong effect on the ABTS radical scavenging activity. SCP and ULLP exhibited excellent hydroxyl radical scavenging activities, about 83.33% ± 2.31% and 80.07% ± 2.17%, respectively, at 4 mg/mL. The

  18. Size resolved airborne particulate polysaccharides in summer high Arctic

    Science.gov (United States)

    Leck, C.; Gao, Q.; Mashayekhy Rad, F.; Nilsson, U.

    2013-04-01

    Size-resolved aerosol samples for subsequent determination of polysaccharides (monosaccharides in combined form) were collected in air over the central Arctic Ocean during the biologically most active period between the late summer melt season and into the transition to autumn freeze-up. The analysis was carried out using liquid chromatography coupled with highly selective and sensitive tandem mass spectrometry. Polysaccharides were detected in all sizes ranging from 0.035 to 10 μm in diameter with distinct features of heteropolysaccharides, enriched in xylose, glucose + mannose as well as a substantial fraction of deoxysugars. Polysaccharides containing deoxysugars showed a bimodal structure with about 60% of their mass found in the Aitken mode over the pack ice area. Pentose (xylose) and hexose (glucose + mannose) showed a weaker bimodal character and were largely found in the coarse mode in addition to a minor fraction apportioned in the sub-micrometer size range. The concentration of total hydrolysable neutral sugars (THNS) in the samples collected varied over 3 orders of magnitude (1 to 692 pmol m-3) in the super-micrometer size fraction and to a lesser extent in sub-micrometer particles (4 to 88 pmol m-3). Lowest THNS concentrations were observed in air masses that had spent more than 5 days over the pack ice. Within the pack ice area, about 53% (by mass) of the total mass of polysaccharides were found in sub-micrometer particles. The relative abundance of sub-micrometer polysaccharides was closely related to the length of time that the air mass spent over pack ice, with highest fraction (> 90%) observed for > 7 days of advection. The ambient aerosol particles collected onboard ship showed similar monosaccharide composition, compared to particles generated experimentally in situ at the open lead site. This supports the existence of a primary source of particulate polysaccharides from open leads by bubble bursting at the air-sea interface. We speculate that

  19. [Monosaccharide composition analysis and its content determination of polysaccharides from Rhaponticum uniforum].

    Science.gov (United States)

    Li, Fa-Sheng; Xu, Heng-Gui; Yan, Xiao-Mei; Li, Ming-Yang; Liu, Hui

    2008-06-01

    To analyze the monosaccharide composition in the polysaccharides from Rhaponticum uniforum, determine the content of monosaccharide, and provide some references for further research. The monosaccharide composition was determined by high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Phenol-sulfuric acid method was used for the determination of the content of polysaccharide. The monosaccharides composition in polysaccharides from R. uniforum are glucose, arabonose and fructose. Their molar ratios are 1 : 1.61 : 2.21. The content of polysaccharide is 95.78%, taking the mixture of monosaccharide compositions as reference substances. HPAEC-PAD can be used to analyze the monosaccharide composition in the polysaccharide with high precision, and the method of phenol-sulfuric acid is simple, convenient and reliable.

  20. Longitudinal multiparameter single-cell analysis of macaques immunized with pneumococcal protein-conjugated or unconjugated polysaccharide vaccines reveals distinct antigen specific memory B cell repertoires.

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    Bin Jia

    Full Text Available The efficacy of protein-conjugated pneumococcal polysaccharide vaccines has been well characterized for children. The level of protection conferred by unconjugated polysaccharide vaccines remains less clear, particularly for elderly individuals who have had prior antigenic experience through immunization with unconjugated polysaccharide vaccines or natural exposure to Streptococcus pneumoniae.We compared the magnitude, diversity and genetic biases of antigen-specific memory B cells in two groups of adult cynomolgus macaques that were immunized with a 7-valent conjugated vaccine and boosted after five years with either a 13-valent pneumococcal polysaccharide conjugate vaccine (13vPnC or a 23-valent unconjugated pneumococcal polysaccharide vaccine (23vPS using microengraving (a single-cell analysis method and single-cell RT-PCR.Seven days after boosting, the mean frequency of antigen-specific memory B cells was significantly increased in macaques vaccinated with 13vPnC compared to those receiving 23vPS. The 13vPnC-vaccinated macaques also exhibited a more even distribution of antibody specificities to four polysaccharides in the vaccine (PS4, 6B, 14, 23F that were examined. However, single-cell analysis of the antibody variable region sequences from antigen-specific B cells elicited by unconjugated and conjugated vaccines indicated that both the germline gene segments forming the heavy chains and the average lengths of the Complementary Determining Region 3 (CDR3 were similar.Our results confirm that distinctive differences can manifest between antigen-specific memory B cell repertoires in nonhuman primates immunized with conjugated and unconjugated pneumococcal polysaccharide vaccines. The study also supports the notion that the conjugated vaccines have a favorable profile in terms of both the frequency and breadth of the anamnestic response among antigen-specific memory B cells.