Oral colonization by yeasts in HIV-positive patients in Brazil

INTRODUCTION: In HIV-infected patients, colonization of the oral cavity by potential pathogenic yeast may lead to development of systemic fungemia. We evaluated the prevalence of yeast in the oral cavity of Brazilian HIV-positive patients and verified whether or not the species characterized were enzymatically active. Furthermore, the species identified were tested for their susceptibility to antifungal treatment. METHODS: Patient saliva and oropharyngeal candidiasis samples were collected from 60 seropositive HIV patients and identified by the API20C system. Enzymatic activity was evaluated by the production of proteinase and phospholipase. Susceptibility to antifungal treatments were determined using the broth microdilution method. RESULTS: the most commonly isolated species were C. albicans (51.56%) followed by non-albicans Candida species (43.73%), Trichosporon mucoides (3.12%) and Kodamaea ohmeri (1.56%). Oral colonization by association of different species was observed in 42% of the patients. Enzymatic activity was verified in most of species isolated, except for C. glabrata, C. lusitaniae and C. guilliermondii. Resistance to Fluconazole and Amphotericin B was observed in isolates of C. albicans, C. glabrata, C. parapsilosis, C. krusei, and K. ohmeri. CONCLUSION: HIV-positive patients are orally colonized by single or multiple species of yeast that are occasionally resistant to Fluconazole or Amphotericin B.INTRODUÇÃO: Em pacientes infectados pelo HIV, a colonização da cavidade bucal por leveduras patogênicas pode levar ao desenvolvimento de fungemias. No presente estudo, avaliamos a prevalência de leveduras na cavidade bucal de pacientes HIV-positivos e verificamos se as espécies isoladas foram enzimaticamente ativas. Além disso, as espécies identificadas foram testadas quanto à suscetibilidade a antifúngicos. MÉTODOS: Amostras de saliva e de candidose orofaríngea foram coletadas de 60 pacientes soropositivos para HIV e identificados pelo sistema API20C. A atividade enzimática foi avaliada pela produção de proteinase e fosfolipase. A suscetibilidade a antifúngicos foi determinada utilizando o método de microdiluição em caldo. RESULTADOS: As espécies mais comumente isoladas foram C. albicans (51,56%), seguido por espécies de Candida não-albicans (43,73%), Trichosporon mucoides (3,12%) e Kodamaea ohmeri (1,56%). A colonização bucal por associação de diferentes espécies foi observada em 42% dos pacientes. A atividade enzimática foi verificada na maioria das espécies isoladas, com exceção de C. glabrata, C. lusitaniae e C. guilliermondii. Resistência ao fluconazol e anfotericina B foi observada em isolados de C. albicans, C. glabrata, C. parapsilosis, C. krusei, e K. ohmeri. CONCLUSÃO: Os pacientes HIV-positivos são colonizados por espécies únicas ou múltiplas de levedura que ocasionalmente são resistentes ao fluconazol ou anfotericina B

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum

Observation of Collider Muon Neutrinos with the SND@LHC Experiment

We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at s=13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb-1. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2<8.4, inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 νμ interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed νμ signal

Measurement of the muon flux at the SND@LHC experiment

The Scattering and Neutrino Detector at the LHC (SND@LHC) started taking data at the beginning of Run 3 of the LHC. The experiment is designed to perform measurements with neutrinos produced in proton-proton collisions at the LHC in an energy range between 100 GeV and 1 TeV. It covers a previously unexplored pseudo-rapidity range of 7.2 < η< 8.4 . The detector is located 480 m downstream of the ATLAS interaction point in the TI18 tunnel. It comprises a veto system, a target consisting of tungsten plates interleaved with nuclear emulsion and scintillating fiber (SciFi) trackers, followed by a muon detector (UpStream, US and DownStream, DS). In this article we report the measurement of the muon flux in three subdetectors: the emulsion, the SciFi trackers and the DownStream Muon detector. The muon flux per integrated luminosity through an 18 × 18 cm 2 area in the emulsion is: 1.5±0.1(stat)×104fb/cm2. The muon flux per integrated luminosity through a 31 × 31 cm 2 area in the centre of the SciFi is: 2.06±0.01(stat)±0.12(sys)×104fb/cm2 The muon flux per integrated luminosity through a 52 × 52 cm 2 area in the centre of the downstream muon system is: 2.35±0.01(stat)±0.10(sys)×104fb/cm2 The total relative uncertainty of the measurements by the electronic detectors is 6 % for the SciFi and 4 % for the DS measurement. The Monte Carlo simulation prediction of these fluxes is 20–25 % lower than the measured values

Observation of Collider Muon Neutrinos with the SND@LHC Experiment

We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at √ s = 13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb − 1 . The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2 < η < 8.4 , inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 ν μ interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed ν μ signal

Search for a vector-like quark T′ → tH via the diphoton decay mode of the Higgs boson in proton-proton collisions at s \sqrt{s} = 13 TeV

A search for the electroweak production of a vector-like quark T′, decaying to a top quark and a Higgs boson is presented. The search is based on a sample of proton-proton collision events recorded at the LHC at = 13 TeV, corresponding to an integrated luminosity of 138 fb−1. This is the first T′ search that exploits the Higgs boson decay to a pair of photons. For narrow isospin singlet T′ states with masses up to 1.1 TeV, the excellent diphoton invariant mass resolution of 1–2% results in an increased sensitivity compared to previous searches based on the same production mechanism. The electroweak production of a T′ quark with mass up to 960 GeV is excluded at 95% confidence level, assuming a coupling strength κT = 0.25 and a relative decay width Γ/MT′ < 5%

Search for massive resonances decaying in to WW,WZ or ZZ bosons in proton-proton collisions at root s=13 TeV

Peer reviewe