Abstract Introduction The nasopharynx and oropharynx are the main colonization sites of coronavirus. Therefore, patients with paranasal sinuses and pharyngeal problems (ear, nose, and throat [ENT] patients) predispose coronavirus infection. Ear, nose, and throat patients with concomitant asymptomatic coronavirus infection may develop severe pneumonia following surgical procedures. As a result, presurgical screening for coronavirus infection is a substantial concern. Objective We evaluated the usefulness of a spiral chest computed tomography (CT) scan in the diagnosis of asymptomatic coronavirus infection in the presurgical assessment of ENT patients Methods In this study, candidates of paranasal sinus or pharyngeal surgery were evaluated for coronavirus infection. Patients with neither history of coronavirus disease 2019 (COVID-19) nor compatible symptoms and signs were screened for asymptomatic coronavirus infection. These patients composed two groups: the first group underwent a reverse transcription polymerase chain reaction (RT-PCR) test of nasopharyngeal sample and spiral chest CTscan, but for the second one, only the latter was performed. Results In the first group, which consisted of 106 patients, 11 (10.4%) cases had positive RT-PCR test results, and 17 (16%) patients showed positive findings in favor of coronavirus infection in the spiral chest CT scan. In the second group, which consisted of 173 patients, 34 (19.7%) cases had positive chest CT scan results. Conclusion The chest CT scan has a valuable role in the early diagnosis of asymptomatic coronavirus carriers in patients highly predisposed to infection, especially in low resource areas, where the RT-PCR test is unavailable.

Abstract Dichlorvos (DDVP) is one of the most consumption chlorinated organophosphate insecticide used on tomato. The knowledge about the influence of postharvest household processes on the levels of DDVP residues in vegetables is required to estimate dietary exposure. In this study, the removal of sprayed dichlorvos (DDVP) on tomato by washing with tap, ozonated water (in dosages of 2, 4 and 6 mg ozone/L), a commercial detergent solution (in concentration of 1, 2 and 3%) and ultrasonic cleaner (with power of 100, 200 and 300 W) was investigated. DDVP residue was determined by gas chromatography with electron capture detector. Washing processes led to the significant reduction of DDVP. The gradual increase in the percentage of the removal was observed due to increment of washing time, ozone dosage, and concentration of detergent solution as well as ultrasonic power. The maximum removal percentage of DDVP after 15 min of washing with tap and ozonated water, a detergent solution and ultrasonic cleaner was 30.7, 91.9, 70.7, and 88.9%, respectively. In general, results indicated washing with tap, ozonated water, a detergent solution and ultrasonic cleaning are effective methods for removal of DDVP from tomato and reduction of its dietary exposure without influence on product quality.

Uma grande variedade de nanomateriais tem demonstrado aplicações médicas promissoras, tais como liberação de fármacos e em imagens. Nestas aplicações, a superfície química dos materiais é crítica, uma vez que exerce papel importante na determinação da toxicidade e comportamento de biodistribuição do material. Aqui, nós revisamos a funcionalização de nanomateriais, como dendrons, como método eficiente de alterar a superfície química destes compostos, introduzindo novas propriedades e funções. Descritos aqui estão nanopartículas superparamagnéticas de óxido de ferro (do inglês, SPIO), com guanidinas dendríticas para aumentar seu transporte para o interior das células, úteis em imagens de ressonância magnética. A introdução de dendrons contendo hidroxilas, aminas, guanidinas, carboidratos e quelatos de Gd(III) periféricos em vesículas poliméricas (polymersomes) também está descrita. Esses grupos dendríticos permitem a modulação de toxicidade, captura celular, ligação à proteína e eficiência como agente de contraste, enquanto que, ao mesmo tempo, permitem a manutenção da estabilidade das vesículas poliméricas. Assim, essa abordagem é promissora para o desenvolvimento de grande variedade de materiais multifuncionais para aplicações farmacêuticas.

A wide variety of nanomaterials have demonstrated promise in medical applications such as drug delivery and imaging. In these applications, the surface chemistry of the materials is critical as it plays an important role in determining the toxicity and biodistribution behavior of the material. We review here the functionalization of nanomaterials with dendrons as an efficient method to alter the surface chemistry of the materials, introducing new properties and functions. Described here is the functionalization of superparamagnetic iron oxide nanoparticles (SPIO) with dendritic guanidines to enhance their transport into cells for magnetic resonance imaging applications. The introduction of dendrons bearing peripheral hydroxyls, amines, guanidines, carbohydrates and Gd(III) chelates to polymer vesicles (polymersomes) is also described. These dendritic moieties allow for modulation of toxicity, cell uptake, protein binding, and contrast agent efficiency, while at the same time allowing the stabilities of the polymersomes to be maintained. Thus, this approach holds promise for the development of a wide range of multifunctional materials for pharmaceutical applications.