Desmistificando o atendimento odontológico para paciente soropositivo: Revisão de literatura / Demystifying dental care for hiv-positive patients: Literature review

O Vírus da Imunodeficiência Humana – HIV surgiu na década de 80 no Brasil, sendo desde então considerado um problema de saúde pública e que ainda é estigmatizado pela sociedade atualmente. É uma infecção que pode levar à Síndrome da Imunodeficiência Adquirida (SIDA), quadro mais avançado da doença. Os últimos dados coletados pelo Ministério da Saúde dão conta de que a infecção pelo vírus tem diminuído ao longo dos anos, e diferente do que se pensa, a maior parte dos infectados se declararam heterossexuais. O risco de exposição ocupacional apesar de ser mínimo, tendo em vista o rigor na adoção as normas de biossegurança, ainda há profissionais que se negam a realizar o tratamento odontológico no paciente soropositivo. Ao passo que a doença se instala no organismo, acomete o sistema imunológico, causando imunossupressão. Diante disso ocorrem os primeiros sinais e sintomas da doença, como as manifestações orais. O objetivo deste trabalho é esclarecer através de uma revisão bibliográfica, os aspectos que ainda contribuem para estigmatização das pessoas vivendo com HIV na busca pela assistência odontológica, tal qual, enfatizar a relevância do cirurgião-dentista na identificação das principais lesões da cavidade oral. Neste contexto, pode-se concluir que apesar dos estigmas ainda prevalecerem em torno desta doença, o cirurgião-dentista deve realizar o atendimento dentro dos mesmos preceitos de biossegurança para qualquer paciente e ter o embasamento teórico suficiente para reconhecer as alterações no meio bucal e o tratamento adequado para este público.

Fibrose cística: uma revisão

A fibrose cística é causada por mutações no gene CFTR, que resultam em disfunção na proteína reguladora da passagem de cloreto e sódio, levando à formação de muco espesso que afeta órgãos como pulmões e pâncreas. A prevalência da doença varia globalmente, sendo mais comum em caucasianos e diagnosticada, na maioria dos casos, durante a infância, especialmente em países com rastreamento neonatal. Fisiologicamente, a fibrose cística provoca infecções respiratórias crônicas e complicações digestivas devido à obstrução dos ductos pancreáticos, além de afetar outras glândulas exócrinas. O diagnóstico inclui exames como o teste do suor e análises genéticas, e o tratamento é focado no controle de sintomas respiratórios e gastrointestinais, com avanços recentes no uso de moduladores de CFTR, que oferecem melhorias significativas na qualidade de vida dos pacientes, embora o acesso a essas terapias ainda seja limitado

AVALIAÇÃO DE RISCO AMBIENTAL DA COMERCIALIZAÇÃO DO PESCADO NA REGIÃO PORTUÁRIA DE MANAUS/AMAZONAS

A segurança alimentar é uma preocupação recorrente, pois trata-se da necessidade de ingestão de alimentos que tenham um padrão de qualidade aceitável, sem risco à saúde. Neste trabalho, avaliam-se as condições de risco ambiental, associadas a uma área de livre comércio de pescado situada em uma região portuária localizada na Zona Sul de Manaus-AM, com 150 m de extensão, entre os igarapés do Educandos e São Raimundo, próxima a importantes locais comerciais; e as condições sanitárias do pescado durante sua comercialização, acondicionamento e descarte. No processo de análise foram consideradas as condições sanitárias do ambiente e do manipulador do alimento. O método utilizado foi a Análise de Falhas, Modos e Efeitos (FMEA). Os resultados demonstram que a aplicação do FMEA para cálculo do risco proporciona a identificação dos pontos críticos e a indicação das melhorias possíveis. Quanto ao local de análise, este encontra-se em um grau de risco variando de moderado a alto. Os fatores que podem ocasionar vetores prejudiciais à saúde pública, pelo manuseio inadequado do pescado, pela infra-estrutura local e higiene dos alimentos foram observados em 64% dos casos. E a geração de efluentes líquidos, resíduos sólidos e o consumo de água sem controle de qualidade foi associada a 36% dos casos. Apesar do quadro desfavorável, esta forma de comércio é uma vocação local e por isso deve passar por um processo de revisão do poder público, para busca de uma qualidade ambiental acompanhada da segurança alimentar do pescado comercializado

First M87 Event Horizon Telescope Results. IX. Detection of Near-horizon Circular Polarization

Event Horizon Telescope (EHT) observations have revealed a bright ring of emission around the supermassive black hole at the center of the M87 galaxy. EHT images in linear polarization have further identified a coherent spiral pattern around the black hole, produced from ordered magnetic fields threading the emitting plasma. Here we present the first analysis of circular polarization using EHT data, acquired in 2017, which can potentially provide additional insights into the magnetic fields and plasma composition near the black hole. Interferometric closure quantities provide convincing evidence for the presence of circularly polarized emission on event-horizon scales. We produce images of the circular polarization using both traditional and newly developed methods. All methods find a moderate level of resolved circular polarization across the image (〈|v|〉 &lt; 3.7%), consistent with the low image-integrated circular polarization fraction measured by the Atacama Large Millimeter/submillimeter Array (|vint| &lt; 1%). Despite this broad agreement, the methods show substantial variation in the morphology of the circularly polarized emission, indicating that our conclusions are strongly dependent on the imaging assumptions because of the limited baseline coverage, uncertain telescope gain calibration, and weakly polarized signal. We include this upper limit in an updated comparison to general relativistic magnetohydrodynamic simulation models. This analysis reinforces the previously reported preference for magnetically arrested accretion flow models.</p

The Variability of the Black Hole Image in M87 at the Dynamical Timescale

The black hole images obtained with the Event Horizon Telescope (EHT) are expected to be variable at the dynamical timescale near their horizons. For the black hole at the center of the M87 galaxy, this timescale (5-61 days) is comparable to the 6 day extent of the 2017 EHT observations. Closure phases along baseline triangles are robust interferometric observables that are sensitive to the expected structural changes of the images but are free of station-based atmospheric and instrumental errors. We explored the day-to-day variability in closure-phase measurements on all six linearly independent nontrivial baseline triangles that can be formed from the 2017 observations. We showed that three triangles exhibit very low day-to-day variability, with a dispersion of ∼3°-5°. The only triangles that exhibit substantially higher variability (∼90°-180°) are the ones with baselines that cross the visibility amplitude minima on the u-v plane, as expected from theoretical modeling. We used two sets of general relativistic magnetohydrodynamic simulations to explore the dependence of the predicted variability on various black hole and accretion-flow parameters. We found that changing the magnetic field configuration, electron temperature model, or black hole spin has a marginal effect on the model consistency with the observed level of variability. On the other hand, the most discriminating image characteristic of models is the fractional width of the bright ring of emission. Models that best reproduce the observed small level of variability are characterized by thin ring-like images with structures dominated by gravitational lensing effects and thus least affected by turbulence in the accreting plasmas.</p

First Sagittarius A* Event Horizon Telescope results. I. The shadow of the supermassive black hole in the center of the Milky Way

We present the first Event Horizon Telescope (EHT) observations of Sagittarius A* (Sgr A*), the Galactic center source associated with a supermassive black hole. These observations were conducted in 2017 using a global interferometric array of eight telescopes operating at a wavelength of λ = 1.3 mm. The EHT data resolve a compact emission region with intrahour variability. A variety of imaging and modeling analyses all support an image that is dominated by a bright, thick ring with a diameter of 51.8 ± 2.3 μas (68% credible interval). The ring has modest azimuthal brightness asymmetry and a comparatively dim interior. Using a large suite of numerical simulations, we demonstrate that the EHT images of Sgr A* are consistent with the expected appearance of a Kerr black hole with mass ∼4 × 106 M⊙, which is inferred to exist at this location based on previous infrared observations of individual stellar orbits, as well as maser proper-motion studies. Our model comparisons disfavor scenarios where the black hole is viewed at high inclination (i &gt; 50°), as well as nonspinning black holes and those with retrograde accretion disks. Our results provide direct evidence for the presence of a supermassive black hole at the center of the Milky Way, and for the first time we connect the predictions from dynamical measurements of stellar orbits on scales of 103–105 gravitational radii to event-horizon-scale images and variability. Furthermore, a comparison with the EHT results for the supermassive black hole M87* shows consistency with the predictions of general relativity spanning over three orders of magnitude in central mass

First Sagittarius A* Event Horizon telescope results. VI. testing the black hole metric

Astrophysical black holes are expected to be described by the Kerr metric. This is the only stationary, vacuum, axisymmetric metric, without electromagnetic charge, that satisfies Einstein’s equations and does not have pathologies outside of the event horizon. We present new constraints on potential deviations from the Kerr prediction based on 2017 EHT observations of Sagittarius A* (Sgr A*). We calibrate the relationship between the geometrically defined black hole shadow and the observed size of the ring-like images using a library that includes both Kerr and non-Kerr simulations. We use the exquisite prior constraints on the mass-to-distance ratio for Sgr A*to show that the observed image size is within ∼10% of the Kerr predictions. We use these bounds to constrain metrics that are parametrically different from Kerr, as well as the charges of several known spacetimes. To consider alternatives to the presence of an event horizon, we explore the possibility that Sgr A* is a compact object with a surface that either absorbs and thermally reemits incident radiation or partially reflects it. Using the observed image size and the broadband spectrum of Sgr A*, we conclude that a thermal surface can be ruled out and a fully reflective one is unlikely. We compare our results to the broader landscape of gravitational tests. Together with the bounds found for stellar-mass black holes and the M87 black hole, our observations provide further support that the external spacetimes of all black holes are described by the Kerr metric, independent of their mass

First Sagittarius A* Event Horizon Telescope results. II. EHT and multiwavelength observations, data Processing, and calibration

We present Event Horizon Telescope (EHT) 1.3 mm measurements of the radio source located at the position of the supermassive black hole Sagittarius A* (Sgr A* ), collected during the 2017 April 5–11 campaign. The observations were carried out with eight facilities at six locations across the globe. Novel calibration methods are employed to account for Sgr A* ʼs flux variability. The majority of the 1.3 mm emission arises from horizon scales, where intrinsic structural source variability is detected on timescales of minutes to hours. The effects of interstellar scattering on the image and its variability are found to be subdominant to intrinsic source structure. The calibrated visibility amplitudes, particularly the locations of the visibility minima, are broadly consistent with a blurred ring with a diameter of ∼50 μas, as determined in later works in this series. Contemporaneous multiwavelength monitoring of Sgr A* was performed at 22, 43, and 86 GHz and at near-infrared and X-ray wavelengths. Several X-ray flares from Sgr A* are detected by Chandra, one at low significance jointly with Swift on 2017 April 7 and the other at higher significance jointly with NuSTAR on 2017 April 11. The brighter April 11 flare is not observed simultaneously by the EHT but is followed by a significant increase in millimeter flux variability immediately after the X-ray outburst, indicating a likely connection in the emission physics near the event horizon. We compare Sgr A* ’s broadband flux during the EHT campaign to its historical spectral energy distribution and find that both the quiescent emission and flare emission are consistent with its long-term behavior.We present Event Horizon Telescope (EHT) 1.3 mm measurements of the radio source located at the position ofthe supermassive black hole Sagittarius A* (Sgr A*), collected during the 2017 April 5–11 campaign. Theobservations were carried out with eight facilities at six locations across the globe. Novel calibration methods areemployed to account for Sgr A*ʼs flux variability. The majority of the 1.3 mm emission arises from horizon scales,where intrinsic structural source variability is detected on timescales of minutes to hours. The effects of interstellarscattering on the image and its variability are found to be subdominant to intrinsic source structure. The calibratedvisibility amplitudes, particularly the locations of the visibility minima, are broadly consistent with a blurred ringwith a diameter of ∼50 μas, as determined in later works in this series. Contemporaneous multiwavelengthmonitoring of Sgr A* was performed at 22, 43, and 86 GHz and at near-infrared and X-ray wavelengths. SeveralX-ray flares from Sgr A* are detected by Chandra, one at low significance jointly with Swift on 2017 April 7 and the other at higher significance jointly with NuSTAR on 2017 April 11. The brighter April 11 flare is not observed simultaneously by the EHT but is followed by a significant increase in millimeter flux variability immediately after the X-ray outburst, indicating a likely connection in the emission physics near the event horizon. We compareSgr A* ’s broadband flux during the EHT campaign to its historical spectral energy distribution and find that both the quiescent emission and flare emission are consistent with its long-term behavio

First Sagittarius A* Event Horizon Telescope Results. IV. Variability, Morphology, and Black Hole Mass

In this paper we quantify the temporal variability and image morphology of the horizon-scale emission from Sgr A* , as observed by the EHT in 2017 April at a wavelength of 1.3 mm. We find that the Sgr A* data exhibit variability that exceeds what can be explained by the uncertainties in the data or by the effects of interstellar scattering. The magnitude of this variability can be a substantial fraction of the correlated flux density, reaching ∼100% on some baselines. Through an exploration of simple geometric source models, we demonstrate that ringlike morphologies provide better fits to the Sgr A* data than do other morphologies with comparable complexity. We develop two strategies for fitting static geometric ring models to the time-variable Sgr A* data; one strategy fits models to short segments of data over which the source is static and averages these independent fits, while the other fits models to the full data set using a parametric model for the structural variability power spectrum around the average source structure. Both geometric modeling and image-domain feature extraction techniques determine the ring diameter to be 51.8 ± 2.3 μas (68% credible intervals), with the ring thickness constrained to have an FWHM between ∼30% and 50% of the ring diameter. To bring the diameter measurements to a common physical scale, we calibrate them using synthetic data generated from GRMHD simulations. This calibration constrains the angular size of the gravitational radius to be 4.8 0.7 1.4 - + μas, which we combine with an independent distance measurement from maser parallaxes to determine the mass of Sgr A* to be 4.0 10 0.6 1.1 ´ 6 - + Me