1,324 research outputs found
B Cells Regulate Neutrophilia during Mycobacterium tuberculosis Infection and BCG Vaccination by Modulating the Interleukin-17 Response
We have previously demonstrated that B cells can shape the immune response to Mycobacterium tuberculosis, including the level of neutrophil infiltration and granulomatous inflammation at the site of infection. The present study examined the mechanisms by which B cells regulate the host neutrophilic response upon exposure to mycobacteria and how neutrophilia may influence vaccine efficacy. To address these questions, a murine aerosol infection tuberculosis (TB) model and an intradermal (ID) ear BCG immunization mouse model, involving both the μMT strain and B cell-depleted C57BL/6 mice, were used. IL (interleukin)-17 neutralization and neutrophil depletion experiments using these systems provide evidence that B cells can regulate neutrophilia by modulating the IL-17 response during M. tuberculosis infection and BCG immunization. Exuberant neutrophilia at the site of immunization in B cell-deficient mice adversely affects dendritic cell (DC) migration to the draining lymph nodes and attenuates the development of the vaccine-induced Th1 response. The results suggest that B cells are required for the development of optimal protective anti-TB immunity upon BCG vaccination by regulating the IL-17/neutrophilic response. Administration of sera derived from M. tuberculosis-infected C57BL/6 wild-type mice reverses the lung neutrophilia phenotype in tuberculous μMT mice. Together, these observations provide insight into the mechanisms by which B cells and humoral immunity modulate vaccine-induced Th1 response and regulate neutrophila during M. tuberculosis infection and BCG immunization. © 2013 Kozakiewicz et al
Resposta terapêutica e profilática com ferro e ácido fólico na anemia em crianças de creches públicas em Goiânia, Goiás, Brasil: ensaio clínico randomizado
The objective of this study was to assess the prevalence of anemia and the therapeutic and prophylactic response to ferrous sulfate and folic acid. A double-blind, randomized, controlled clinical trial was conducted with 196 children 6 to 24 months of age enrolled in municipal daycare centers in Goiânia, Goiás State, Brazil. The children were assigned to two treatment groups that received a daily dose (5 times a week) of either 4.2mg/kg/day of ferrous sulfate + folic acid (50µg) or 4.2mg/kg/day of ferrous sulfate + folic acid placebo. One of the prevention groups received 1.4mg/kg/day of ferrous sulfate + folic acid (50µg/day) and the other 1.4mg/kg/day of ferrous sulfate + folic acid placebo. Supplementation lasted approximately three months. Baseline anemia prevalence was 56.1% (95%CI: 48.9-63.1). After treatment, anemia prevalence in the folic acid group (14%) was lower than in the placebo group (34.9%) (p = 0.02). After prophylaxis in the non-anemic children, the incidence of anemia did not differ between the groups, but there was an increase in hemoglobin level in the folic acid group (p = 0.003). Iron plus folic acid was effective for the treatment of anemia and improvement of hemoglobin level in non-anemic children.Avaliar a prevalência de anemia e a resposta terapêutica e profilática do sulfato ferroso e ácido fólico. Realizou-se um ensaio clínico controlado randomizado, duplo-cego, com 196 crianças de 6 a 24 meses, dos Centros Municipais de Educação Infantil de Goiânia, Goiás, Brasil. As crianças foram alocadas em dois grupos de tratamento que receberam dose diária (5x/semana) com 4,2mg/kg/dia de sulfato ferroso + ácido fólico (50µg) ou 4,2mg/kg/dia de sulfato ferroso + placebo de ácido fólico. Um dos grupos de prevenção recebeu 1,4 mg/kg/dia de sulfato ferroso + ácido fólico (50µg/dia) e o outro 1,4mg/kg/dia de sulfato ferroso + placebo de ácido fólico. A suplementação durou cerca de três meses. A prevalência de anemia inicial foi de 56,1% (IC95%: 48,9-63,1). Após o tratamento, a prevalência de anemia no grupo ácido fólico (14%) foi menor que no grupo placebo (34,9%; p = 0,02). Após profilaxia dos não anêmicos, a incidência de anemia não diferiu entre os grupos, porém, houve incremento da hemoglobina no grupo ácido fólico (p = 0,003). O ferro associado com ácido fólico foi eficaz no tratamento da anemia e na melhoria da hemoglobina nos não anêmicos.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de Goiás Faculdade de NutriçãoUniversidade Federal de São Paulo (UNIFESP)Universidade Federal de Goiás Instituto de Patologia Tropical e Saúde PúblicaVila São José Bento CotolengoUNIFESPSciEL
Performance of the CMS Cathode Strip Chambers with Cosmic Rays
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device
in the CMS endcaps. Their performance has been evaluated using data taken
during a cosmic ray run in fall 2008. Measured noise levels are low, with the
number of noisy channels well below 1%. Coordinate resolution was measured for
all types of chambers, and fall in the range 47 microns to 243 microns. The
efficiencies for local charged track triggers, for hit and for segments
reconstruction were measured, and are above 99%. The timing resolution per
layer is approximately 5 ns
Macrofossil evidence for a rapid and severe Cretaceous–Paleogene mass extinction in Antarctica
Debate continues about the nature of the Cretaceous–Paleogene (K–Pg) mass extinction event. An abrupt crisis triggered by a bolide impact contrasts with ideas of a more gradual extinction involving flood volcanism or climatic changes. Evidence from high latitudes has also been used to suggest that the severity of the extinction decreased from low latitudes towards the poles. Here we present a record of the K–Pg extinction based on extensive assemblages of marine macrofossils (primarily new data from benthic molluscs) from a highly expanded Cretaceous–Paleogene succession: the López de Bertodano Formation of Seymour Island, Antarctica. We show that the extinction was rapid and severe in Antarctica, with no significant biotic decline during the latest Cretaceous, contrary to previous studies. These data are consistent with a catastrophic driver for the extinction, such as bolide impact, rather than a significant contribution from Deccan Traps volcanism during the late Maastrichtian
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
Intelligent biofilm detection with ensemble of deep learning networks
Dental biofilm is traditionally identified visually, which can be challenging and time-consuming due to its color similarity with the tooth. The aim of this study was to evaluate the performance of U-Net neural networks for the automatic detection of dental biofilm without disclosing agents on intraoral photographs of deciduous and permanent teeth using an ensemble strategy. This retrospective exploratory study was conducted on two datasets of intraoral images obtained from deciduous and permanent dentitions. The first dataset was used to validate dental biofilm annotations by an expert with disclosing agents. The second dataset, without disclosing agents, was employed to train and evaluate the U-Net neural network in the identification of dental biofilms using an ensemble strategy. The performance of the ensemble method was assessed using a cross-validation procedure, with six groups dedicated to training, one group for validation, and one group exclusively taken as a test set for the final evaluation of the ensemble. The performance of the neural network was evaluated using accuracy, F1 score, sensitivity, and specificity. The U-Net neural network achieved an accuracy of 93.1%, sensitivity of 65.1%, specificity of 95.9%, and an F1 score of 63.0%. The U-Net neural network using the ensemble strategy was able to automatically identify visually detecTable dental biofilms on intraoral photographs. The application of this new knowledge will soon be available in clinical practice
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
Effect of Virulence Factors on the Photodynamic Inactivation of Cryptococcus neoformans
Opportunistic fungal pathogens may cause an array of superficial infections or serious invasive infections, especially in immunocompromised patients. Cryptococcus neoformans is a pathogen causing cryptococcosis in HIV/AIDS patients, but treatment is limited due to the relative lack of potent antifungal agents. Photodynamic inactivation (PDI) uses the combination of non-toxic dyes called photosensitizers and harmless visible light, which produces singlet oxygen and other reactive oxygen species that produce cell inactivation and death. We report the use of five structurally unrelated photosensitizers (methylene blue, Rose Bengal, selenium derivative of a Nile blue dye, a cationic fullerene and a conjugate between poly-L-lysine and chlorin(e6)) combined with appropriate wavelengths of light to inactivate C. neoformans. Mutants lacking capsule and laccase, and culture conditions that favoured melanin production were used to probe the mechanisms of PDI and the effect of virulence factors. The presence of cell wall, laccase and melanin tended to protect against PDI, but the choice of the appropriate photosensitizers and dosimetry was able to overcome this resistance.Fundação de Amparo à Pesquisa do Estado de São Paulo (2010/13313–9
Kallmann syndrome: a hystorical, clinical and molecular review
Kallmann syndrome (KS), the association of hypogonadotropic hypogonadism and anosmia, was described by Maestre de San Juan in 1856 and characterized as a hereditary condition by Franz Josef Kallmann in 1944. Many aspects such as pathogeny, phenotype and genotype in KS were described in the last fifteen years. The knowledge of this condition has grown fast, making it difficult to update. Here we review historical aspects of this condition and its discoverers and describe new findings regarding the embryogenesis of the olfactory bulb and GnRH secreting neuronal tracts that are important for understanding the association of hypogonadism and anosmia. Additionally, we describe the phenotypic and genotypic heterogeneity of KS, including five related genes (KAL-1, FGFR1, PROKR2, PROK2 e NELF), and discuss the function of each codified protein in migration and maturation of the olfactory and GnRH neurons, with data from in vitro and in vivo studies. Finally we describe the clinical phenotype of patients carrying these mutations.A síndrome de Kallmann (SK) é a associação de hipogonadismo hipogonadotrófico (HH) e anosmia descrita por Maestre de San Juan, em 1856, e caracterizada como condição hereditária por Franz Josef Kallmann, em 1944. Muitos aspectos de sua patogenia, variabilidade fenotípica e genotípica foram desvendados nos últimos 15 anos. Conseqüentemente, tem sido difícil manter-se atualizado frente à rapidez que o conhecimento dessa condição é gerado. Nesta revisão, resgatamos aspectos históricos pouco conhecidos sobre a síndrome e seus descobridores; incorporamos novas descobertas relacionadas à embriogênese dos neurônios olfatórios e produtores de GnRH. Esse processo é fundamental para compreender a associação de hipogonadismo e anosmia; descrevemos a heterogeneidade fenotípica e genotípica, incluindo mutações em cinco genes (KAL-1, FGFR1, PROKR2, PROK2 e NELF). Para cada gene, discutimos a função da proteína codificada na migração e maturação dos neurônios olfatórios e GnRH a partir de estudos in vitro e modelos experimentais e descrevemos características clínicas dos portadores dessas mutações.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de MedicinaUNIFESP, EPM, Depto. de MedicinaSciEL
- …
