Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 548
Filtrar
1.
Med Klin Intensivmed Notfmed ; 119(3): 236-248, 2024 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-38441579

RESUMO

Emergency situations involving the ears, nose, and throat (ENT) area can pose considerable challenges for clinicians and often require an interdisciplinary approach due to the involvement of different organ systems. To avoid damage to highly relevant sensory and perception organs and life-threatening bleeding or respiratory complications, strategies that are as quick and targeted as possible are necessary. This article aims to provide an overview of ENT emergency management strategies. The entire spectrum from simple conservative to highly complex surgical measures plays a role here, both diagnostically and therapeutically. Aspects such as bleeding, respiratory problems, inflammation, hearing disorders, vertigo, facial palsy and injuries to the head and neck area are discussed. In addition, important topics such as preventive measures and possible complications are also addressed to ensure optimal patient care.


Assuntos
Emergências , Nariz , Humanos , Nariz/lesões , Inflamação
3.
Waste Manag ; 176: 140-148, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38281345

RESUMO

The effect of operational conditions on the stability of acidogenic fermentation (AF) devoted to volatile fatty acids (VFAs) production still presents numerous gaps to achieve high yields and fully understand the responses of open microbiomes associated to this technology. To cope with that, this investigation was designed to assess the stability of VFAs production via AF of agro-food wastes at high hydraulic retention times (HRTs) (20 and 30 d) and pH oscillations (5.8-6.2). Similar bioconversion efficiencies (∼50 %) were reached regardless of the HRT, revealing that HRT of 20 d can be considered as a threshold from which, no further improvement was achieved. The combination of long HRTs, 25 °C and acid pHs promoted a robust microbiome that resulted in a stable outcome against pH variations, being Clostridiales order identified as key player of AF stability. These conditions mediated a high selectivity in the VFAs production profile, with acetic and butyric acids, prevailing in the VFAs pool (∼80 % of total VFAs) at HRT 20 d. The selection of appropriated conditions was shown to be critical to maximize the hydrolysis and acidogenesis of the substrate and attain a stable effluent against pH oscillations.


Assuntos
Reatores Biológicos , Ácidos Graxos Voláteis , Fermentação , Ácidos , Concentração de Íons de Hidrogênio , Anaerobiose , Esgotos
4.
Rhinology ; 62(1): 55-62, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37772802

RESUMO

BACKGROUND: Although the COVID-19 pandemic has increased the prevalence of cases with olfactory loss, other respiratory viruses can also cause this condition. We aimed to compare the prevalence of acute SARS-CoV-2 infection and other respiratory viruses in patients with sudden smell loss, and to assess the impact of SARS-CoV-2 viral load and co-infection on olfactory symptoms. METHODS: Patients with sudden smell loss were recruited in a multicenter prospective cohort study in 15 hospitals in Brazil. Clinical questionnaire, Connecticut Chemosensory Clinical Research Center (CCCRC) olfactory test and nasopharyngeal swab to perform a PCR-based respiratory viral panel were collected at first visit (day 0) and 30 and 60 days after recruitment. RESULTS: 188 of 213 patients presented positive test result for SARS-CoV-2, among which 65 were co-infected with other respiratory viruses (e.g., rhinovirus, enterovirus, and parainfluenza). 25 had negative test results for SARS-CoV-2. Patients in both SARSCoV-2 and non-SARS-CoV-2 groups had objective anosmia (less than 2 points according to the psychophysical olfactory CCCRC) at day 0, with no significant difference between them. Both groups had significant smell scores improvement after 30 and 60 days, with no difference between them. Co-infection with other respiratory viruses, and SARS-CoV-2 viral load did not impact olfactory scores. CONCLUSION: Patients with sudden smell loss associated with SARS-CoV-2 and other respiratory viruses had similar presentation, with most participants initiating with anosmia, and total or near total recovery after 60 days. SARS-CoV-2 viral load and co-infections with other respiratory viruses were not associated with poorer olfactory outcomes.


Assuntos
COVID-19 , Coinfecção , Transtornos do Olfato , Humanos , SARS-CoV-2 , COVID-19/complicações , Anosmia/complicações , Anosmia/epidemiologia , Estudos Prospectivos , Pandemias , Coinfecção/complicações , Coinfecção/epidemiologia , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/etiologia , Olfato
5.
bioRxiv ; 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38014127

RESUMO

Behavioral interactions within the nuclear family may play a pivotal role in the emergence of autonomy and agency in mammals. While the emergence of a behavior may arise over weeks in line with nervous system maturation, individual events occur on sub-second time scales. This makes it uniquely challenging to track development in the lab where observations are made over minutes to hours or in ecological studies which lack individual specificity and sub-second precision. Here we study families of gerbils, a highly social rodent, raised in enlarged home-cage environments over weeks of development, using continuous video recordings to capture tens of millions of time points per family. Focusing on postnatal day 15 (when pups leave the nest) to day 30 (around the time when pups would disperse) we identify distinct developmental trajectories for both autonomous behaviors (exploration, food and water foraging), and social behaviors (huddling, approach, time spent together). Most of these behaviors emerge in concert with clear diurnal and crepuscular patterns and we find sex differences in both autonomous and social behaviors. Our work supports the emergence of distinct autonomous and social behavior phenotypes as the behavioral correlates of critical developmental periods of maturation of the rodent brain and can form the basis of future research on development from both neuroscience and behavioral biology perspectives.

6.
Sensors (Basel) ; 23(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37896641

RESUMO

This paper presents the concept of a novel adaptable sensing solution currently being developed under the EU Commission-founded PHOTONGATE project. This concept will allow for the quantification of multiple analytes of the same or different nature (chemicals, metals, bacteria, etc.) in a single test with levels of sensitivity and selectivity at/or over those offered by current solutions. PHOTONGATE relies on two core technologies: a biochemical technology (molecular gates), which will confer the specificity and, therefore, the capability to be adaptable to the analyte of interest, and which, combined with porous substrates, will increase the sensitivity, and a photonic technology based on localized surface plasmonic resonance (LSPR) structures that serve as transducers for light interaction. Both technologies are in the micron range, facilitating the integration of multiple sensors within a small area (mm2). The concept will be developed for its application in health diagnosis and food safety sectors. It is thought of as an easy-to-use modular concept, which will consist of the sensing module, mainly of a microfluidics cartridge that will house the photonic sensor, and a platform for fluidic handling, optical interrogation, and signal processing. The platform will include a new optical concept, which is fully European Union Made, avoiding optical fibers and expensive optical components.


Assuntos
Metais , Ressonância de Plasmônio de Superfície , Metais/química , Óptica e Fotônica , Bactérias , Fibras Ópticas
7.
Arch Pharm (Weinheim) ; 356(12): e2300294, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37821361

RESUMO

Natural products belonging to different chemical classes have been established as a promising source of novel anticancer drugs. Several low-molecular-weight compounds from the classes of monoterpenes, phenylpropanoids, and flavonoids were shown to possess anticancer activities in previous studies. In this work, over 20 semisynthetic derivatives of molecules belonging to these classes, namely thymol, eugenol, and 6-hydroxyflavanone were synthesized and tested for their cytotoxicity against two human cancer cell lines, namely AGS cells (gastric adenocarcinoma) and A549 cells (human lung carcinoma). An initial screening based on viability assessment was performed to identify the most cytotoxic compounds at 100 µM. The results evidenced that two 6-hydroxyflavanone derivatives were the most cytotoxic among the compounds tested, being selected for further studies. These derivatives displayed enhanced toxicity when compared with their natural counterparts. Moreover, the lactate dehydrogenase (LDH) assay showed that the loss of cell viability was not accompanied by a loss of membrane integrity, thus ruling out a necrotic process. Morphological studies with AGS cells demonstrated chromatin condensation compatible with apoptosis, confirmed by the activation of caspase 3/7. Furthermore, a viability assay on a noncancer human embryonic lung fibroblast cell line (MRC-5) confirmed that these two derivatives possess selective anticancer activity.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Células A549 , Neoplasias Pulmonares/patologia , Apoptose , Proliferação de Células
8.
Nature ; 621(7980): 716-722, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37758891

RESUMO

Einstein's general theory of relativity from 19151 remains the most successful description of gravitation. From the 1919 solar eclipse2 to the observation of gravitational waves3, the theory has passed many crucial experimental tests. However, the evolving concepts of dark matter and dark energy illustrate that there is much to be learned about the gravitating content of the universe. Singularities in the general theory of relativity and the lack of a quantum theory of gravity suggest that our picture is incomplete. It is thus prudent to explore gravity in exotic physical systems. Antimatter was unknown to Einstein in 1915. Dirac's theory4 appeared in 1928; the positron was observed5 in 1932. There has since been much speculation about gravity and antimatter. The theoretical consensus is that any laboratory mass must be attracted6 by the Earth, although some authors have considered the cosmological consequences if antimatter should be repelled by matter7-10. In the general theory of relativity, the weak equivalence principle (WEP) requires that all masses react identically to gravity, independent of their internal structure. Here we show that antihydrogen atoms, released from magnetic confinement in the ALPHA-g apparatus, behave in a way consistent with gravitational attraction to the Earth. Repulsive 'antigravity' is ruled out in this case. This experiment paves the way for precision studies of the magnitude of the gravitational acceleration between anti-atoms and the Earth to test the WEP.

9.
Eur Rev Med Pharmacol Sci ; 27(8): 3622-3630, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140313

RESUMO

OBJECTIVE: Confocal laser endomicroscopy (CLE) allows the visualization of epithelium in a thousand-fold magnification. This study analyzes the architectural differences at the cellular level of the mucosa and squamous cell carcinoma (SCC). PATIENTS AND METHODS: A total of 60 CLE sequences recorded in 5 patients with SCC undergoing laryngectomy between October 2020 and February 2021 were analyzed. The corresponding histologic sample derived from H&E staining was assigned to each sequence, capturing CLE images of the tumor and healthy mucosa. In addition, the cellular structure analysis was performed to diagnose SCC by measuring the total number of cells and cell size in 60 sequences in a fixed field of view (FOV) with 240 µm in diameter (45,239 µm2). RESULTS: Out of 3,600 images, 1,620 (45%) showed benign mucosa and 1,980 (55%) SCC. The automated analysis yielded a difference in cell size, with healthy epithelial cells being 171.9±82.0 µm2 smaller than SCC cells, which were 246.3±171.9 µm2 and showed greater variability in size (p=0.037). In addition, due to the probe's fixed FOV, there was a difference in cell count with a total of 188.7±38.3 and 124.8±38.6 cells in images of normal epithelium and SCC (p<0.001), respectively. Regarding cell density as a criterion for the differentiation of benign/malign, using a cut-off value of 145.5 cells/FOV, we obtained sensitivity and specificity of 88.0% and 71.9%, respectively. CONCLUSIONS: SCC reveals marked differences at a cellular level compared to the healthy epithelium. Our results further support the importance of this feature for identifying SCC during CLE imaging.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Microscopia Confocal/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carcinoma de Células Escamosas/patologia , Contagem de Células , Lasers
10.
Molecules ; 28(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37049869

RESUMO

Melanoma is the deadliest type of skin cancer, with about 61,000 deaths annually worldwide. Late diagnosis increases mortality rates due to melanoma's capacity to metastasise rapidly and patients' resistance to the available conventional therapies. Consequently, the interest in natural products as a strategy for drug discovery has been emerging. Propolis, a natural product produced by bees, has several biological properties, including anticancer effects. Propolis from Gerês is one of the most studied Portuguese propolis. Our group has previously demonstrated that an ethanol extract of Gerês propolis collected in 2018 (G18.EE) and its fractions (n-hexane, ethyl acetate, and n-butanol) decrease melanoma cell viability. Out of all the fractions, G18.EE-n-BuOH showed the highest potential as a melanoma pharmacological therapy. Thus, in this work, G18.EE-n-BuOH was fractioned into 17 subfractions whose effect was evaluated in A375 BRAF-mutated melanoma cells. The subfractions with the highest cytotoxic activity were analysed by UPLC-DAD-ESI/MSn in an attempt to understand which phenolic compounds could account for the anti-melanoma activity. The compounds identified are typical of the Gerês propolis, and some of them have already been linked with antitumor effectiveness. These results reaffirm that propolis compounds can be a source of new drugs and the isolation of compounds could allow its use in traditional medicine.


Assuntos
Antineoplásicos , Melanoma , Própole , Neoplasias Cutâneas , Humanos , Própole/farmacologia , Portugal , Melanoma/tratamento farmacológico , Antineoplásicos/farmacologia , Fenóis/farmacologia
11.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769330

RESUMO

The demand for new fluorophores for different biological target imaging is increasing. Benzo[a]phenoxazine derivatives are fluorochromophores that show promising optical properties for bioimaging, namely fluorescent emission at the NIR of the visible region, where biological samples have minimal fluorescence emission. In this study, six new benzo[a]phenoxazinium chlorides possessing sulfonamide groups at 5-amino-positions were synthesized and their optical and biological properties were tested. Compared with previous probes evaluated using fluorescence microscopy, using different S. cerevisiae strains, these probes, with sulfonamide groups, stained the vacuole membrane and/or the perinuclear membrane of the endoplasmic reticulum with great specificity, with some fluorochromophores capable of even staining the plasma membrane. Thus, the addition of a sulfonamide group to the benzo[a]phenoxazinium core increases their specificity and attributes for the fluorescent labeling of cell applications and fractions, highlighting them as quite valid alternatives to commercially available dyes.


Assuntos
Corantes Fluorescentes , Vacúolos , Saccharomyces cerevisiae , Retículo Endoplasmático , Coloração e Rotulagem , Membrana Celular , Imagem Óptica
13.
Acta Biomater ; 155: 667-683, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36328124

RESUMO

The host inflammatory response to biomaterials conditions their capacity to promote tissue repair, and macrophage polarization shift from M1 to M2 is determinant in this process. Previous work showed that extracts of a combination between fibrinogen and metallic magnesium materials acted synergistically to reduce macrophage inflammatory phenotype. The hypothesis underlying the current work was that the ability of magnesium-modified fibrinogen scaffolds to modulate macrophage phenotype depends on the concentration of magnesium. Thus, Fibrinogen (Fg) scaffolds incorporating precise concentrations of magnesium sulfate (Mg: 0, 10, 25, 50 mM) were developed and characterized. Mg incorporation in Fg scaffolds increased surface charge, while porosity decreased with increasing Mg concentrations, but only Fg scaffolds with 10 mM of Mg (FgMg10) had significantly improved mechanical properties. Human macrophages cultured on FgMg10 scaffolds, showed increased M2 and decreased M1 polarization, when compared to those cultured on scaffolds with 0, 25 and 50 mM of Mg. Macrophage polarization results were independent of the anion used (chloride or sulfate). Macrophage modulation by FgMg10 scaffolds involved reduced NF-κB p65 nuclear translocation, and impacted production of pro-inflammatory mediators (e.g. IFNγ, IL-12, TNF-⍺, IP-10). Importantly, FgMg10 scaffolds implanted in vivo increased the expression of M2 marker CD163, in macrophages from inflammatory exudates, compared to Sham and Fg-implanted animals, increasing the M2:M1 ratio. A cytokine/chemokine array showed that, while both Fg and FgMg10 scaffolds decreased inflammatory mediators, only FgMg10 decreased IL-1ß, IP-10, MIP-2, MDC and MIP-3⍺, compared to Sham-operated animals. This study demonstrated that incorporation of 10mM of Mg modulated inflammation, promoting M2 macrophage polarization in vitro and in vivo. STATEMENT OF SIGNIFICANCE: Developing biomaterials that can modulate inflammation and promote macrophage phenotype switch from M1 to M2 is crucial to promote a regenerative microenvironment. Our previous work showed that extracts of a combination between fibrinogen (Fg) and metallic magnesium (Mg) materials synergistically reduced macrophage pro-inflammatory phenotype. Herein, we tested the hypothesis that macrophage modulation was dependent on Mg concentration. A new family of Fg porous scaffolds incorporating different amounts of Mg (0, 10, 25 and 50 mM) was produced and characterized. We observed that only the combination of Fg scaffolds with 10 mM of Mg (FgMg10) significantly changed the scaffolds mechanical properties and directed macrophages towards a M2 phenotype, reducing the production of inflammatory mediators, both in vitro and in vivo.


Assuntos
Fibrinogênio , Magnésio , Animais , Humanos , Materiais Biocompatíveis/metabolismo , Quimiocina CXCL10/metabolismo , Fibrinogênio/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Magnésio/farmacologia , Magnésio/metabolismo , Fenótipo
14.
Photochem Photobiol ; 99(5): 1282-1292, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36524439

RESUMO

The antifungal performance and the possible use as fluorescent probes of a series of squarylium dyes derived from indolenine and benzo[e]indole previously synthesized was evaluated. Some photophysical properties were performed in ethanol and phosphate buffer, and the type of aggregates form in phosphate buffer was analyzed. Using the 1,3-diphenylisobenzofuran assay, a qualitative assessment of the capacity of dyes to produce singlet oxygen after irradiation was performed. Regarding the antifungal activity, this was studied through a broth microdilution assay using Saccharomyces cerevisiae PYCC 4072 as a biological model. The effect of irradiation of the dyes, with an appropriate light emitting diode system, on the antifungal activity was also evaluated, and it was verified that some of the dyes improve their activity after irradiation. Using fluorescence microscopy techniques, the colocalization of dyes in S. cerevisae cells was investigated and it was possible to verify that some of the squarylium dyes with a barbituric moiety in the four-membered central ring stained and accumulated preferentially in the mitochondrial web and perinuclear membrane of the cells. The possible use as a fluorescent probe for the detection of HSA was also evaluated for one of the dyes of the series, demonstrating a linear variation in the fluorescence intensity accompanied by the increase in the protein concentration.

15.
Rev. esp. anestesiol. reanim ; 69(10): 680-682, dic. 2022.
Artigo em Espanhol | IBECS | ID: ibc-211946

RESUMO

El manejo del dolor durante una toracotomía y tras ella es difícil en neonatos prematuros. Las técnicas de bloqueo ecoguiado en el plano fascial, tales como el bloqueo en el plano del músculo erector de la columna, son técnicas de anestesia regional relativamente nuevas que han surgido como alternativa a la anestesia epidural torácica, debido a su efectividad clínica, facilidad de administración y ejecución, teóricamente más segura. La facilidad relativa de identificar las referencias anatómicas, en comparación con el bloqueo paravertebral, así como su perfil de seguridad comparado con la anestesia epidural, pueden haber contribuido a la creciente popularidad del bloqueo músculo erector de la columna. Sin embargo, actualmente la evidencia publicada en cuanto a la eficacia de las técnicas de anestesia regional en neonatos de bajo peso intervenidos con esta cirugía es limitada, debido a los pocos informes de casos aislados. Describimos aquí el uso del bloqueo unilateral en el plano del músculo erector de la columna, como parte de la anestesia y la analgesia postoperatoria en la corrección quirúrgica de la atresia esofágica en un recién nacido prematuro.(AU)


Pain management during and after thoracotomy is challenging in premature neonates. Ultrasound-guided fascial plane block techniques, such as the erector spinae plane block are a relatively new regional anesthesia technique and have emerged as an alternative to thoracic epidural due to its clinical effectiveness, ease of administration and theoretically being safer to perform. The relative ease of identifying anatomical landmarks compared to the paravertebral block, as well as its safety profile compared to an epidural, may have contributed to the erector spinae plane Bs growing popularity. Currently, however, the published evidence for the efficacy of regional anesthesia techniques in low birth weight newborns undergoing this surgery is limited to few isolated case reports. Herein we describe the use of unilateral erector spinae plane block as part of anesthesia and postoperative analgesia management of surgical correction of esophageal atresia in a preterm neonate.(AU)


Assuntos
Humanos , Feminino , Adulto , Atresia Esofágica/cirurgia , Recém-Nascido , Manejo da Dor , Toracotomia , Anestesia por Condução , Pacientes Internados , Anestesiologia , Pediatria , Exame Físico
16.
Rev Esp Anestesiol Reanim (Engl Ed) ; 69(10): 680-682, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344410

RESUMO

Pain management during and after thoracotomy is challenging in premature neonates. Ultrasound-guided fascial plane block techniques, such as the erector spinae plane block are a relatively new regional anesthesia technique and have emerged as an alternative to thoracic epidural due to its clinical effectiveness, ease of administration and theoretically being safer to perform. The relative ease of identifying anatomical landmarks compared to the paravertebral block, as well as its safety profile compared to an epidural, may have contributed to the erector spinae plane Bs growing popularity. Currently, however, the published evidence for the efficacy of regional anesthesia techniques in low birth weight newborns undergoing this surgery is limited to few isolated case reports. Herein we describe the use of unilateral erector spinae plane block as part of anesthesia and postoperative analgesia management of surgical correction of esophageal atresia in a preterm neonate.


Assuntos
Atresia Esofágica , Bloqueio Nervoso , Recém-Nascido , Humanos , Dor Pós-Operatória , Atresia Esofágica/cirurgia , Bloqueio Nervoso/métodos , Músculos Paraespinais , Toracotomia
17.
Nanomaterials (Basel) ; 12(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36296773

RESUMO

A recently synthesized new eugenol derivative, ethyl 4-(2-methoxy-4-(oxiran-2-ylmethyl)phenoxy)butanoate, with a high insecticidal activity against Sf9 (Spodoptera frugiperda) insect cells, was encapsulated in the liposomal formulations of egg-phosphatidylcholine/cholesterol (Egg-PC:Ch) 70:30 and 100% dioleoylphosphatidylglycerol (DOPG), aiming at the future application as insecticides. Compound-loaded DOPG liposomes have sizes of 274 ± 12 nm, while Egg-PC:Ch liposomes exhibit smaller hydrodynamic diameters (69.5 ± 7 nm), high encapsulation efficiency (88.8 ± 2.7%), higher stability, and a more efficient compound release, thus, they were chosen for assays in Sf9 insect cells. The compound elicited a loss of cell viability up to 80% after 72 h of incubation. Relevantly, nanoencapsulation maintained the toxicity of the compound toward insect cells while lowering the toxicity toward human cells, thus showing the selectivity of the system. Structure-based inverted virtual screening was used to predict the most likely targets and molecular dynamics simulations and free energy calculations were used to demonstrate that this molecule can form a stable complex with insect odorant binding proteins and/or acetylcholinesterase. The results are promising for the future application of compound-loaded nanoliposome formulations as crop insecticides.

18.
Phys Rev Lett ; 129(2): 024802, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867433

RESUMO

A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.

19.
J Environ Manage ; 311: 114895, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299134

RESUMO

The management of radioactive waste is a worldwide activity based on the guidelines of the International Atomic Energy Agency (IAEA), and all stages of management require scientifically proven methods for possible deployment. The management of radioactive waste is a huge challenge due to the high risk in the collection, gathering, transport, handling, and storage. In this study, a thermal plasma treatment process was evaluated for its efficiency to process solid radioactive waste. Experiments were carried out with the application of stable isotopes of Lead, Iodine, Cobalt, and Cesium. After the thermal plasma treatments, the slag and the residual gas were analyzed to verify the influence of process time and discharge power on the efficiency of the process. The treatment for 25 min and 10 kW was sufficient to reduce the mass by 50% of the slag. When the applied power was increased to 15 kW, an expressive reduction in the treatment time (10 min) was able to promote the same mass reduction. The results indicated that the treatment of radioactive waste by thermal plasma is a promising method to manage and reduce the mass and volume for the final disposal.

20.
Photochem Photobiol ; 98(6): 1402-1417, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35348226

RESUMO

Four squaraine dyes derived from 2,3,3-trimethylindolenine and 1,1,2-trimethyl-1H-benzo[e]indole with different combinations of barbituric groups attach to the central ring, having ester groups and alkyl chains in the nitrogen atoms of heterocyclic rings were synthesized. These dyes were fully characterized, and their photophysical behavior was studied in ethanol and phosphate-buffered solution. Absorption and emission bands between 631 and 712 nm were detected, with the formation of aggregates in aqueous media, which is typical of this class of dyes. Tests carried out with 1,3-diphenylisobenzofuran allowed us to verify the ability of the dyes to produce singlet oxygen. The interaction of synthesized dyes with human serum albumin (HSA) was also evaluated, being demonstrated a linear correlation between fluorescence intensity and protein concentration. The antifungal potential of the dyes against the yeast Saccharomyces cerevisiae was evaluated using a broth microdilution assay. In order to test the photosensitizing capacity of the synthesized dyes, tests were carried out in the dark and with irradiation, using a custom-built light-emitting diode that emits close to the absorption wavelength of the studied dyes. The results showed that the interaction of dyes with HSA and the antifungal activity depends on the different structural modifications of the dyes.


Assuntos
Antifúngicos , Corantes Fluorescentes , Humanos , Corantes Fluorescentes/química , Antifúngicos/farmacologia , Albumina Sérica Humana , Indóis
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...