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1.
J Biol Regul Homeost Agents ; 32(5): 1323-1328, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30334433

RESUMO

Oral bacteria that degrade sulphur-containing amino acids (cysteine, cystine, and methionine) produce volatile sulphur compounds (VSCs = hydrogen sulphide, methyl mercaptan, and dimethyl sulphide) highly correlated with halitosis. When these bacteria are given the right environment, i.e. periodontal disease, cariogenic biofilm or food source they can grow in number very quickly and will start to convert proteins to VSC that, together with volatile fatty acids are largely responsible for oral malodor. Recently, the prevention of dental caries and periodontal diseases using various probiotics has been attempted. The purpose of this study was to investigate the effects of probiotics based on in vitro analysis, such as antibacterial activity, and to evaluate the neutralizing effect of probiotics on halitosis, the levels of VSCs were measured by gas chromatography. .


Assuntos
Halitose/dietoterapia , Halitose/microbiologia , Doenças Periodontais/dietoterapia , Doenças Periodontais/microbiologia , Probióticos/uso terapêutico , Compostos de Enxofre/análise , Cromatografia Gasosa , Halitose/metabolismo , Humanos , Técnicas In Vitro , Odorantes/análise , Odorantes/prevenção & controle , Doenças Periodontais/metabolismo
2.
J Biol Regul Homeost Agents ; 32(5): 1329-1334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30334434

RESUMO

Dental plaque-related diseases (cavities, gingivitis, periodontitis and halitosis) have been traditionally controlled by mechanical non-specific removal of plaque. However, many novel treatment approaches aim to inhibit the growth of pathogenic bacteria or to remove their toxins. Probiotics are viable microorganisms which, when administered in adequate amounts, provide a health benefit to the host. Recently, probiotics have been applied as new tools for the improvement of dental health. They have been used to substitute existing antibiotic treatments due to increased resistant bacteria. Probiotics not only have antibacterial activity, but they also have inhibitory effects on the reappearance of oral pathogenic bacteria. The aim of this study was to assess the clinical effect of the administration of probiotics agents in the treatment of mild to moderate periodontitis.


Assuntos
Saúde Bucal , Doenças Periodontais/dietoterapia , Doenças Periodontais/microbiologia , Probióticos/uso terapêutico , Humanos , Probióticos/administração & dosagem
3.
J Biol Regul Homeost Agents ; 31(4): 901-910, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29254292

RESUMO

Dental tissues represent an alternative and promising source of post-natal Mesenchymal stem cells (MSCs) for tissue engineering. Furthermore, dental stem cells from apical papilla (SCAPs) cells can be obtained from the wisdom tooth which is unnecessary for human masticatory function and frequently extracted for orthodontic reasons or dysodontiasis. More precisely, apical papilla is the immature, mostly uncalcified, precursor of the tooth root, therefore is composed of more undifferentiated cells than dental pulp. In addition, tooth extraction, especially by piezosurgery technique, can be considered less invasive in comparison to bone marrow or other tissues biopsy. Our work is aimed to investigate the safety of and predictable procedure on surgical immature third molar extraction and to provide new insight on SCAP research for future biomedical applications. The isolated cells were examined for stem cell properties by analyzing their colony-forming efficiency, differentiation characteristics and the expression of MSC markers.


Assuntos
Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Osteogênese/genética , Raiz Dentária/citologia , Adolescente , Biomarcadores/metabolismo , Diferenciação Celular , Proliferação de Células , Separação Celular , Criança , Ensaio de Unidades Formadoras de Colônias , Polpa Dentária/metabolismo , Feminino , Expressão Gênica , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Dente Molar/cirurgia , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Engenharia Tecidual , Extração Dentária , Raiz Dentária/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Phys Rev Lett ; 110(1): 012301, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23383780

RESUMO

Measurements of charge-dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudorapidity range |η| < 0.8 are presented as a function of the collision centrality, particle separation in pseudorapidity, and transverse momentum. A clear signal compatible with a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. This provides a new insight for understanding the nature of the charge-dependent azimuthal correlations observed at RHIC and LHC energies.

7.
Phys Rev Lett ; 110(3): 032301, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23373913

RESUMO

The charged-particle pseudorapidity density measured over four units of pseudorapidity in nonsingle-diffractive p+Pb collisions at a center-of-mass energy per nucleon pair √(s(NN))=5.02 TeV is presented. The average value at midrapidity is measured to be 16.81±0.71 (syst), which corresponds to 2.14±0.17 (syst) per participating nucleon, calculated with the Glauber model. This is 16% lower than in nonsingle-diffractive pp collisions interpolated to the same collision energy and 84% higher than in d+Au collisions at s√(s(NN))=0.2 TeV. The measured pseudorapidity density in p+Pb collisions is compared to model predictions and provides new constraints on the description of particle production in high-energy nuclear collisions.

8.
9.
Phys Rev Lett ; 111(23): 232302, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24476260

RESUMO

The directed flow of charged particles at midrapidity is measured in Pb-Pb collisions at √(s(NN))=2.76 TeV relative to the collision symmetry plane defined by the spectator nucleons. A negative slope of the rapidity-odd directed flow component with approximately 3 times smaller magnitude than found at the highest RHIC energy is observed. This suggests a smaller longitudinal tilt of the initial system and disfavors the strong fireball rotation predicted for the LHC energies. The rapidity-even directed flow component is measured for the first time with spectators and found to be independent of pseudorapidity with a sign change at transverse momenta p(T) between 1.2 and 1.7 GeV/c. Combined with the observation of a vanishing rapidity-even p(T) shift along the spectator deflection this is strong evidence for dipolelike initial density fluctuations in the overlap zone of the nuclei. Similar trends in the rapidity-even directed flow and the estimate from two-particle correlations at midrapidity, which is larger by about a factor of 40, indicate a weak correlation between fluctuating participant and spectator symmetry planes. These observations open new possibilities for investigation of the initial conditions in heavy-ion collisions with spectator nucleons.

10.
Phys Rev Lett ; 111(16): 162301, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24182258

RESUMO

We report on the first measurement of inclusive J/ψ elliptic flow v2 in heavy-ion collisions at the LHC. The measurement is performed with the ALICE detector in Pb-Pb collisions at √(s(NN))=2.76 TeV in the rapidity range 2.5

11.
Phys Rev Lett ; 111(22): 222301, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24329443

RESUMO

The ALICE measurement of K(S)(0) and Λ production at midrapidity in Pb-Pb collisions at √(s(NN))=2.76 TeV is presented. The transverse momentum (p(T)) spectra are shown for several collision centrality intervals and in the p(T) range from 0.4 GeV/c (0.6 GeV/c for Λ) to 12 GeV/c. The p(T) dependence of the Λ/K(S)(0) ratios exhibits maxima in the vicinity of 3 GeV/c, and the positions of the maxima shift towards higher p(T) with increasing collision centrality. The magnitude of these maxima increases by almost a factor of three between most peripheral and most central Pb-Pb collisions. This baryon excess at intermediate p(T) is not observed in pp interactions at √s=0.9 TeV and at √s=7 TeV. Qualitatively, the baryon enhancement in heavy-ion collisions is expected from radial flow. However, the measured p(T) spectra above 2 GeV/c progressively decouple from hydrodynamical-model calculations. For higher values of p(T), models that incorporate the influence of the medium on the fragmentation and hadronization processes describe qualitatively the p(T) dependence of the Λ/K(S)(0) ratio.

12.
Phys Rev Lett ; 111(10): 102301, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-25166659

RESUMO

Azimuthally anisotropic distributions of D0, D+, and D*+ mesons were studied in the central rapidity region (|y|<0.8) in Pb-Pb collisions at a center-of-mass energy sqrt[sNN]=2.76 TeV per nucleon-nucleon collision, with the ALICE detector at the LHC. The second Fourier coefficient v2 (commonly denoted elliptic flow) was measured in the centrality class 30%-50% as a function of the D meson transverse momentum pT, in the range 2-16 GeV/c. The measured v2 of D mesons is comparable in magnitude to that of light-flavor hadrons. It is positive in the range 2

13.
Phys Rev Lett ; 110(15): 152301, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-25167254

RESUMO

We report the first measurement of the net-charge fluctuations in Pb-Pb collisions at sqrt[sNN]=2.76 TeV, measured with the ALICE detector at the CERN Large Hadron Collider. The dynamical fluctuations per unit entropy are observed to decrease when going from peripheral to central collisions. An additional reduction in the amount of fluctuations is seen in comparison to the results from lower energies. We examine the dependence of fluctuations on the pseudorapidity interval, which may account for the dilution of fluctuations during the evolution of the system. We find that the fluctuations at the LHC are smaller compared to the measurements at the BNL Relativistic Heavy Ion Collider, and as such, closer to what has been theoretically predicted for the formation of a quark-gluon plasma.

15.
Phys Rev Lett ; 109(25): 252301, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23368453

RESUMO

In this Letter we report the first results on π(±), K(±), p, and p production at midrapidity (|y|<0.5) in central Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV, measured by the ALICE experiment at the LHC. The p(T) distributions and yields are compared to previous results at sqrt[s(NN)] = 200 GeV and expectations from hydrodynamic and thermal models. The spectral shapes indicate a strong increase of the radial flow velocity with sqrt[s(NN)], which in hydrodynamic models is expected as a consequence of the increasing particle density. While the K/π ratio is in line with predictions from the thermal model, the p/π ratio is found to be lower by a factor of about 1.5. This deviation from thermal model expectations is still to be understood.

16.
Phys Rev Lett ; 109(25): 252302, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23368454

RESUMO

The first measurement of neutron emission in electromagnetic dissociation of ^{208}Pb nuclei at the LHC is presented. The measurement is performed using the neutron zero degree calorimeters of the ALICE experiment, which detect neutral particles close to beam rapidity. The measured cross sections of single and mutual electromagnetic dissociation of Pb nuclei at sqrt[s(NN)]=2.76 TeV with neutron emission are σ(singleEMD)=187.4 ± 0.2(stat)(-11.2)(+13.2) (syst) b and σ(mutualEMD) = 5.7 ± 0.1(stat) ± 0.4(syst) b, respectively. The experimental results are compared to the predictions from a relativistic electromagnetic dissociation model.

18.
Phys Rev Lett ; 109(7): 072301, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-23006362

RESUMO

The ALICE experiment has measured the inclusive J/ψ production in Pb-Pb collisions at √s(NN) = 2.76 TeV down to zero transverse momentum in the rapidity range 2.5 < y < 4. A suppression of the inclusive J/ψ yield in Pb-Pb is observed with respect to the one measured in pp collisions scaled by the number of binary nucleon-nucleon collisions. The nuclear modification factor, integrated over the 0%-80% most central collisions, is 0.545 ± 0.032(stat) ± 0.083(syst) and does not exhibit a significant dependence on the collision centrality. These features appear significantly different from measurements at lower collision energies. Models including J/ψ production from charm quarks in a deconfined partonic phase can describe our data.

19.
Phys Rev Lett ; 108(8): 082001, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22463524

RESUMO

The ALICE Collaboration has studied J/ψ production in pp collisions at √s=7 TeV at the LHC through its muon pair decay. The polar and azimuthal angle distributions of the decay muons were measured, and results on the J/ψ polarization parameters λ(θ) and λ(φ) were obtained. The study was performed in the kinematic region 2.5

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