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2.
Eur J Clin Microbiol Infect Dis ; 31(2): 185-92, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21744281

RESUMO

The purpose of this study was to compare clinical features of Clostridium difficile infection (CDI) to toxin gene profiles of the strains isolated from Danish hospitalized patients. C. difficile isolates were characterized by PCR based molecular typing methods including toxin gene profiling and analysis of deletions and truncating mutations in the toxin regulating gene tcdC. Clinical features were obtained by questionnaire. Thirty percent of the CDI cases were classified as community-acquired. Infection by C. difficile with genes encoding both toxin A, toxin B and the binary toxin was significantly associated with hospital-acquired/healthcare-associated CDI compared to community-acquired CDI. Significantly higher leukocyte counts and more severe clinical manifestations were observed in patients infected by C. difficile containing genes also encoding the binary toxin together with toxin A and B compared to patients infected by C. difficile harbouring only toxin A and B. In conclusion, infection by C. difficile harbouring genes encoding both toxin A, toxin B and the binary toxin were associated with hospital acquisition, higher leukocyte counts and severe clinical disease.


Assuntos
Clostridioides difficile/classificação , Clostridioides difficile/genética , Infecções por Clostridium/microbiologia , Enterocolite Pseudomembranosa/microbiologia , Adolescente , Adulto , Idoso , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Criança , Pré-Escolar , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/patologia , Estudos de Coortes , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/patologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/patologia , Dinamarca , Enterocolite Pseudomembranosa/patologia , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Repressoras/genética , Índice de Gravidade de Doença , Adulto Jovem
3.
Food Microbiol ; 26(2): 136-41, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19171254

RESUMO

Sago starch is an important dietary carbohydrate in lowland Papua New Guinea (PNG). An investigation was conducted to determine whether microbes play a role in its preservation using traditional methods. In 12 stored sago samples collected from PNG villages, lactic acid bacteria (LAB) were present (> or = 3.6 x 10(4)cfu/g) and pH ranged from 6.8 to 4.2. Acetic and propionic acids were detected in all samples, while butyric, lactic and valeric acids were present in six or more. In freshly prepared sago, held in sealed containers in the laboratory at 30 degrees C, spontaneous fermentation by endogenous microflora of sago starch was observed. This was evident by increasing concentrations of acetic, butyric and lactic acids over 4 weeks, and pH reducing from 4.9 to 3.1: both LAB and yeasts were involved. Survival of potential bacterial pathogens was monitored by seeding sago starch with approximately 10(4)/g of selected organisms. Numbers of Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus fell to < 30/g within 7 days. Salmonella sp. was present only in low numbers after 7 days (< 36/g), but Escherichia coli was still detectable after three weeks (> 10(2)/g). Fermentation appeared to increase the storability and safety of the product.


Assuntos
Antibiose , Qualidade de Produtos para o Consumidor , Fermentação , Lactobacillus/metabolismo , Amido/metabolismo , Leveduras/metabolismo , Bacillus cereus/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/fisiologia , Listeria monocytogenes/crescimento & desenvolvimento , Papua Nova Guiné , Staphylococcus aureus/crescimento & desenvolvimento , Fatores de Tempo , Leveduras/crescimento & desenvolvimento , Leveduras/fisiologia
4.
Phys Rev Lett ; 101(11): 112003, 2008 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-18851276

RESUMO

Inclusive K_{S};{0}K_{S};{0} production in ep collisions at the DESY ep collider HERA was studied with the ZEUS detector using an integrated luminosity of 0.5 fb;{-1}. Enhancements in the mass spectrum were observed and are attributed to the production of f_{2}(1270)/a_{2};{0}(1320), f_{2};{'}(1525) and f_{0}(1710). Masses and widths were obtained using a fit which takes into account theoretical predictions based on SU(3) symmetry arguments, and are consistent with the Particle Data Group values. The f_{0}(1710) state, which has a mass consistent with a glueball candidate, was observed with a statistical significance of 5 standard deviations. However, if this state is the same as that seen in gammagamma-->K_{S};{0}K_{S};{0}, it is unlikely to be a pure glueball state.

5.
Phys Rev Lett ; 96(15): 152001, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16712149

RESUMO

Using 420 pb(-1) of data collected on the upsilon(5S) resonance with the CLEO III detector, we reconstruct B mesons in 25 exclusive decay channels to measure or set upper limits on the decay rate of upsilon(5S) into B meson final states. We measure the inclusive B cross section to be sigma(upsilon(5S) --> BB(X)) = (0.177 +/- 0.030 +/- 0.016) nb and make the first measurements of the production rates of sigma(upsilon(5S) --> B*B*) = (0.131 +/- 0.025 +/- 0.014) nb and sigma(upsilon(5S) --> BB*) = (0.043 +/- 0.016 +/- 0.006) nb, respectively. We set 90% confidence level limits of sigma(upsilon(5S) -->BB) < 0.038 nb, sigma(upsilon(5S) --> B(*)B(*)pi) < 0.055 nb and sigma(upsilon(5S) --> BBpipi) < 0.024 nb. We also extract the most precise value of the B(s)* mass to date, M(B(s)*) = (5411.7 +/- 1.6 +/- 0.6) MeV/c2.

6.
Phys Rev Lett ; 96(16): 162003, 2006 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-16712216

RESUMO

Using data collected with the CLEO detector operating at the CESR e+e- collider at sqrt[s]=3.97-4.26 GeV, we investigate 15 charmonium decay modes of the psi(4040), psi(4160), and Y(4260) resonances. We confirm, at 11 sigma significance, the BABAR Y(4260)-->pi+pi- J/psi discovery, make the first observation of Y(4260)--> pi(0)pi(0) J/psi (5.1 sigma), and find the first evidence for Y(4260)-->K+K- J/psi(3.7 sigma). We measure e+e- cross sections at sqrt[s]=4.26 GeV as sigma(pi+pi- J/psi)=58(+12)(-10)+/-4 pb, sigma(pi(0)pi(0) J/psi)=23(+12)(-8)+/-1 pb, and sigma(K+K- J/psi)=9(+9)(-5)+/-1 pb, in which the uncertainties are statistical and systematic, respectively. Upper limits are placed on other decay rates from all three resonances.

7.
Int J Tuberc Lung Dis ; 5(5): 462-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11336278

RESUMO

OBJECTIVE: To evaluate the QuantiFERON-TB test in BCG-vaccinated, non-BCG-vaccinated and tuberculosis (TB) patient donor groups, and to compare its diagnostic performance with that of a blood test based on the Mycobacterium tuberculosis specific antigens ESAT-6 and CFP-10. DESIGN: Analysis of the IFN-gamma responses of whole blood cells from BCG-vaccinated or non-BCG-vaccinated donors or patients with tuberculosis, stimulated with PPD, ESAT-6 or CFP-10 antigens, and evaluation of the specificity and sensitivity of the test. RESULTS: None of the non-vaccinated donors showed positive responses to M. tuberculosis-PPD, ESAT-6 or CFP-10. In BCG-vaccinated donors, 9/19 (47%) donors responded to the QuantiFERON-TB test based on M. tuberculosis-PPD, whereas 2/19 (10.5%) responded to either ESAT-6 or CFP-10. Comparable levels of sensitivity were obtained with the QuantiFERON-TB test based on M. tuberculosis-PPD (79%) and ESAT-6 or CFP-10 antigens (72%). CONCLUSION: Our results demonstrate that the whole blood test based on M. tuberculosis-PPD did not efficiently distinguish BCG-vaccinated donors from individuals with disease due to M. tuberculosis. The introduction of new recombinant antigens specific for M. tuberculosis, such as ESAT-6 or CFP-10, should increase the specificity of the whole blood test and enable discrimination between TB infection, atypical mycobacterial reactivity and reactivity due to BCG vaccination. Such a test would provide a quantum improvement over the current practice of using the tuberculin skin test for TB control and elimination.


Assuntos
Antígenos de Bactérias , Proteínas de Bactérias , Interferon gama/sangue , Tuberculina , Tuberculose/diagnóstico , Adulto , Vacina BCG , Biomarcadores , Humanos , Sensibilidade e Especificidade
10.
Infect Immun ; 68(1): 214-20, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10603390

RESUMO

Culture filtrate from Mycobacterium tuberculosis contains protective antigens of relevance for the generation of a new antituberculosis vaccine. We have identified two previously uncharacterized M. tuberculosis proteins (TB7.3 and TB10.4) from the highly active low-mass fraction of culture filtrate. The molecules were characterized, mapped in a two-dimensional electrophoresis reference map of short-term culture filtrate, and compared with another recently identified low-mass protein, CFP10 (F. X. Berthet, P. B. Rasmussen, I. Rosenkrands, P. Andersen, and B. Gicquel. Microbiology 144:3195-3203, 1998), and the well-described ESAT-6 antigen. Genetic analyses demonstrated that TB10.4 as well as CFP10 belongs to the ESAT-6 family of low-mass proteins, whereas TB7.3 is a low-molecular-mass protein outside this family. The proteins were expressed in Escherichia coli, and their immunogenicity was tested in cultures of peripheral blood mononuclear cells from human tuberculosis (TB) patients, Mycobacterium bovis BCG-vaccinated donors, and nonvaccinated donors. The two ESAT-6 family members, TB10.4 and CFP10, were very strongly recognized and induced gamma interferon release at the same level (CFP10) as or at an even higher level (TB10.4) than ESAT-6. The non-ESAT-6 family member, TB7.3, for comparison, was recognized at a much lower level. CFP10 was found to distinguish TB patients from BCG-vaccinated donors and is, together with ESAT-6, an interesting candidate for the diagnosis of TB. The striking immunodominance of antigens within the ESAT-6 family is discussed, and hypotheses are presented to explain this targeting of the immune response during TB infection.


Assuntos
Antígenos de Bactérias/química , Proteínas de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Bactérias/genética , Vacina BCG/genética , Vacina BCG/isolamento & purificação , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sequência de Bases , Primers do DNA/genética , Humanos , Epitopos Imunodominantes/química , Epitopos Imunodominantes/genética , Técnicas In Vitro , Interferon gama/biossíntese , Ativação Linfocitária , Dados de Sequência Molecular , Peso Molecular , Mycobacterium tuberculosis/genética , Coelhos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Homologia de Sequência de Aminoácidos , Tuberculose/imunologia , Tuberculose/prevenção & controle
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