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1.
Sci Total Environ ; 947: 174661, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38992372

RESUMO

The standard techniques for monitoring beach litter focus on the litter that is accumulated on beaches. Therefore, the underwater bathing area is usually overlooked. Our study aims to start the discussion about the litter in the bathing area, an important connection between the exposed beach and the ocean. We aimed to compare sampling methodologies between the underwater bathing area and the exposed beach. We highlighted litter's similarities and differences regarding the amount, material, possible sources, and interaction with the biota. We also performed a brand audit on the underwater bathing area litter. In the underwater region, 106 items were collected while 1706 items were collected from the exposed beach region. Plastic was the dominant type of material in both sites, exposed beach (89.92 %) and bathing area (83.96 %). The litter's possible source was different. In the underwater bathing area was more related to food packages (couscous, rice). On the other hand, litter on the exposed beach was associated with beach use (single-use plastic such as plastic cups). The brand audit identified 21 companies, whereby most brands were Brazilian and food-related. Regarding interactions with the biota, the litter in the bathing area had more bio-fouling (87.73 %) than the litter collected on the exposed beach (10.00 %). Information about bathing area litter can be useful to draw different management strategies. Due to the differences in litter types and behavior between the two sites, the same mitigation strategies might not be equally efficient.


Assuntos
Praias , Monitoramento Ambiental , Plásticos , Praias/estatística & dados numéricos , Monitoramento Ambiental/métodos , Plásticos/análise , Brasil
2.
Artigo em Inglês | MEDLINE | ID: mdl-33392718

RESUMO

Animals that live in changing environments need to adjust their metabolism to maintain body functions, and sensing these changing conditions is essential for mediating the short- and long-term physiological and behavioral responses that make these adjustments. Previous research on nematodes and insects facing changing oxygen levels has shown that these animals rapidly respond using atypical soluble guanylyl cyclases (sGCs) as oxygen sensors connected to downstream cGMP pathways, and they respond more slowly using hypoxia-inducible transcription factors (HIFs) that are further modulated by oxygen-sensing prolyl hydroxylases (PHs). Crustaceans are known to respond in different ways to hypoxia, but the mechanisms responsible for sensing oxygen levels are more poorly understood than in nematodes and insects. Our paper reviews the functions of and mechanisms underlying oxygen sensing in crustaceans. Furthermore, using the oxygen sensing abilities of nematodes and insects as guides in analyzing available crustacean transcriptomes, we identified orthologues of atypical sGCs, HIFs, and PHs in crustaceans, including in their chemosensory organs and neurons. These molecules include atypical sGCs activated by hypoxia (Gyc-88E/GCY-31 and Gyc-89D/GCY-33) but not those activated by hyperoxia (GCY-35, GCY-36), as well as orthologues of HIF-α, HIF-ß, and PH. We offer possible directions for future research on oxygen sensing by crustaceans.


Assuntos
Crustáceos/fisiologia , Animais , Células Quimiorreceptoras/metabolismo , Neurônios/metabolismo , Oxigênio/metabolismo
3.
Pharmaceutics ; 12(9)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933144

RESUMO

Phytol is a diterpene alcohol and can be found as a product of the metabolism of chlorophyll in plants. This compound has been explored as a potential antimicrobial agent, but it is insoluble in water. In this study, we describe a novel approach for an interesting anticandidal drug delivery system containing phytol. Different formulations of phytol-loaded solid lipid nanoparticles (SLN) were designed and tested using a natural lipid, 1,3-distearyl-2-oleyl-glycerol (TG1). Different compositions were considered to obtain three formulations with 1:10, 1:5, and 1:3 w/w phytol/TG1 ratios. All the formulations were prepared by emulsification solvent evaporation method and had their physicochemical properties assessed. The biocompatibility assay was performed in the HEK-293 cell line and the antifungal efficacy was demonstrated in different strains of Candida ssp., including different clinical isolates. Spherical and uniform SLN (<300 nm, PdI < 0.2) with phytol-loading efficiency >65% were achieved. Phytol-loaded SLN showed a dose-dependent cytotoxic effect in the HEK-293 cell line. The three tested formulations of phytol-loaded SLN considerably enhanced the minimal inhibitory concentration of phytol against 15 strains of Candida spp. Considering the clinical isolates, the formulations containing the highest phytol/TG1 ratios showed MICs at 100%. Thus, the feasibility and potential of phytol-loaded SLN was demonstrated in vitro, being a promising nanocarrier for phytol delivery from an anticandidal approach.

4.
J Therm Biol ; 91: 102617, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32716867

RESUMO

An increase in environmental temperature can deleteriously affect organisms. This study investigated whether the semiterrestrial estuarine crab Neohelice granulata uses emersion behavior as a resource to avoid thermal stress and survive higher aquatic temperatures. We also examined whether this behavior is modulated by exposure to high temperature; whether, during the period of emersion, the animal loses heat from the carapace to the medium; and whether this behavior is altered by the temperature at which the animal has been acclimated. The lethal temperature for 50% of the population (LT50) was determined through 96-h mortality curves in animals acclimated at 20 °C and 30 °C. The behavioral profile of N. granulata during thermal stress was based on monitoring crab movement in aerial, intermediary, and aquatic zones. Acclimation at a higher temperature and the possibility of emersion increased the thermotolerance of the crabs and the synergistic effect of acclimation temperature. The possibility of leaving the hot water further increased the resistance of these animals to thermal stress. We observed that when the crab was subjected to thermal stress conditions, it spent more time in the aerial environment, unlike under control conditions. Under the experimental conditions, it made small incursions into the aquatic environment and stayed in the aerial environment for a longer time in order to cool its body temperature. The animals acclimated at 20 °C and placed into water at 35 °C remained in the aerial zone. The animals acclimated and maintained at 30 °C (control) that were placed in water at 35 °C with the possibility of emerging into hot air transited more frequently between the aquatic and aerial zones than did the animals that were put in water at 35 °C with the possibility of emerging into a cooler air environment. We conclude that emergence behavior allows N. granulata to survive high temperatures and that this behavior is influenced by acclimation temperature.


Assuntos
Comportamento Animal , Braquiúros/fisiologia , Termotolerância , Animais , Movimento
5.
Planta Med ; 86(7): 505-515, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32247285

RESUMO

Spondias mobin leaves have been traditionally used for treating cold sores. The study investigated the mechanism of antiherpes action of S. mombin extract, fractions, and geraniin. Different concentrations of samples were used to evaluate the in vitro antiherpes activity (anti-HSV-1) in virucidal, post-infection, attachment, and penetration assays. The mechanism of action of geraniin was investigated considering the glycoproteins gB and gD of HSV-1 surface as potential molecular targets. Molecular docking simulations were carried out for both in order to determine the possible binding mode position of geraniin at the activity sites. The binding mode position was posteriorly optimized considering the flexibility of the glycoproteins. The chemical analysis of samples was performed by LC-MS and revealed the presence of 22 substances, which are hydrolysable tannins, O-glycosylated flavonoids, phenolic acids, and a carbohydrate. The extract, tannin-rich fraction and geraniin showed important in vitro virucidal activity through blocking viral attachment but showed no relevant inhibition of viral penetration. The in silico approaches demonstrated a high number of potential strong intermolecular interactions as hydrogen bonds between geraniin and the activity site of the glycoproteins, particularly the glycoprotein gB. In silico experiments indicated that geraniin is at least partially responsible for the anti-herpes activity through interaction with the viral surface glycoprotein gB, which is responsible for viral adsorption. These results highlight the therapeutic potential of S. mombin anti-herpes treatment and provides support for its traditional purposes. However, further studies are required to validate the antiviral activities in vivo, as well as efficacy in humans.


Assuntos
Anacardiaceae , Antivirais , Herpes Simples , Herpesvirus Humano 1 , Herpesvirus Humano 2 , Humanos , Simulação de Acoplamento Molecular , Extratos Vegetais , Folhas de Planta , Células Vero , Replicação Viral
6.
Pharmaceutics ; 10(4)2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513856

RESUMO

Chloroquine diphosphate (CQ) is a hydrophilic drug with low entrapment efficiency in hydrophobic nanoparticles (NP). Herpes simplex virus type 1 (HSV-1) is an enveloped double-stranded DNA virus worldwide known as a common human pathogen. This study aims to develop chloroquine-loaded poly(lactic acid) (PLA) nanoparticles (CQ-NP) to improve the chloroquine anti- HSV-1 efficacy. CQ-NP were successfully prepared using a modified emulsification-solvent evaporation method. Physicochemical properties of the NP were monitored using dynamic light scattering, atomic force microscopy, drug loading efficiency, and drug release studies. Spherical nanoparticles were produced with modal diameter of <300 nm, zeta potential of -20 mv and encapsulation efficiency of 64.1%. In vitro assays of CQ-NP performed in Vero E6 cells, using the MTT-assay, revealed different cytotoxicity levels. Blank nanoparticles (B-NP) were biocompatible. Finally, the antiviral activity tested by the plaque reduction assay revealed greater efficacy for CQ-NP compared to CQ at concentrations equal to or lower than 20 µg mL-1 (p < 0.001). On the other hand, the B-NP had no antiviral activity. The CQ-NP has shown feasible properties and great potential to improve the antiviral activity of drugs.

7.
An Acad Bras Cienc ; 90(3): 2855-2864, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29947678

RESUMO

The aim of this study was to evaluate the efficacy and safety of several anesthetics in the brachyuran crab Neohelice granulata, an emergent experimental model. The essential oils (EOs) of Lippia alba, Aloysia tryphilla, and Melaleuca alternifolia (tea tree oil; TTO), the isolated compounds eugenol, menthol, terpinen-4-ol, and the nanoencapsulated form of TTO, were administered in one or more of the following ways: added to the water (immersion), through an arthrodial membrane (injected), or by oral gavage. Unexpectedly, most EOs did not produce an anesthetic effect after immersion. Only TTO and eugenol induced anesthesia by immersion, with very long induction and recovery times compared to anesthesia of other crustaceans. However, a good anesthetic effect was observed with the injection of terpinen-4-ol and nanoencapsulated TTO in N. granulata; both demonstrated ideal induction and recovery times. These substances appear to be promising anesthetic alternatives for crustaceans.


Assuntos
Anestésicos/farmacologia , Braquiúros/efeitos dos fármacos , Melaleuca/química , Nanocápsulas , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Animais , Masculino
8.
Trop Med Int Health ; 20(12): 1707-10, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26426773

RESUMO

OBJECTIVE: To present results of virological surveillance and epidemiological aspects of dengue in the State of Rio Grande do Norte, Brazil. METHODS: A total of 1581 cases, reported from 2010 to 2012 at various health centres in the state, were analysed by viral isolation and/or RT-PCR for viral detection and typing. To identify whether different genotypes were circulating in the state during this period, sequencing of the complete E gene for DENV (1485 bp in length) was performed directly from patient serum samples. RESULTS: All four serotypes of dengue virus circulated in Rio Grande do Norte, with the introduction of DENV-4 in the state in 2011. In 2012, DENV-4 represented 100% of positive confirmed cases. 53.97% of cases occurred in Natal. Case numbers peaked in April (21%) and May (23%). Genetic characterisation of circulating strains confirmed the circulation of genotypes V, south-east Asian/American and II, respectively, for DENV-1, DENV-2 and DENV-4. CONCLUSIONS: This work furthers a better understanding of dengue viruses in the State of Rio Grande do Norte. Strengthening control efforts in the region is important considering the impact of dengue.


Assuntos
Vírus da Dengue/genética , Dengue/epidemiologia , Epidemias , Genótipo , Filogenia , Adolescente , Adulto , Brasil/epidemiologia , Criança , Pré-Escolar , Dengue/virologia , Surtos de Doenças , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Vigilância da População , Prevalência , Sorotipagem/métodos , Adulto Jovem
9.
Physiol Behav ; 151: 97-101, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26177544

RESUMO

The air exposure behavior of the semi-terrestrial crab Neohelice granulata during severe hypoxia was studied. This study also verified whether this behavior mitigates possible oxidative damage, namely lipoperoxidation, caused by hypoxia and reoxygenation cycles. The lethal time for 50% of the crabs subjected to severe hypoxia (0.5 mgO2 · L(-1)) with free access to air was compared to that of crabs subjected to severe hypoxia without access to air. Crabs were placed in aquaria divided into three zones: water (when the animal was fully submersed), land (when the animal was completely emerged) and intermediate (when the animal was in contact with both environments) zones. Then the crabs were held in this condition for 270 min, and the time spent in each zone was recorded. Lipid peroxidation (LPO) damage to the walking leg muscles was determined for the following four experimental conditions: a--normoxic water with free access to air; b--hypoxic water without access to air; c--hypoxic water followed by normoxic water without air access; and d--hypoxic water with free access to air. When exposed to hypoxic water, N. granulata spent significantly more time on land, 135.3 ± 17.7 min, whereas control animals (exposed to normoxic water) spent more time submerged, 187.4 ± 20.2 min. By this behavior, N. granulata was able to maintain a 100% survival rate when exposed to severe hypoxia. However, N. granulata must still return to water after periods of air exposure (~ 14 min), causing a sequence of hypoxia/reoxygenation events. Despite increasing the survival rate, hypoxia with air access does not decrease the lipid peroxidation damage caused by the hypoxia and reoxygenation cycle experienced by these crabs.


Assuntos
Ar , Comportamento Animal/fisiologia , Braquiúros/fisiologia , Peroxidação de Lipídeos , Oxigênio/fisiologia , Animais , Extremidades/fisiologia , Masculino , Músculos/fisiologia , Índice de Gravidade de Doença , Análise de Sobrevida , Fatores de Tempo , Água
10.
Rev. bras. enferm ; Rev. bras. enferm;54(2): 253-260, abr.-jun. 2001.
Artigo em Português | LILACS, BDENF - Enfermagem | ID: lil-312552

RESUMO

Estudo histórico social, cujo objetivo é descrever a trajetória de Zaíra Cintra Vidal, sua inserção na Escola de Enfermeiras Rachel Haddock Lobo e sua participação na Associação Brasileira de Enfermagem (ABEn). O estudo fundamenta-se nos conceitos de poder simbólico, habitus e luta simbólica de Pierre Bourdieu. As fontes primárias foram documentos existentes no Centro de Documentação da EEAN/UFRJ e no Centro de Memória da FENF/UERJ. Os dados foram obtidos no período de agosto de 2000 a abril de 2001 mediante um roteiro de análise documental. Os resultados evidenciaram que Zaíra Cintra Vidal, nasceu em 05 de maio de 1903, graduou-se pela Escola de Enfermeiras do Departamento Nacional de Saúde Pública, em 1926; pós-graduou-se nos EUA de 1927 a 1929, retornando em 1943. Criou a Escola de Enfermeiras Rachel Haddock Lobo, sendo a primeira diretora por nove anos e participou na diretoria da ABEn e na redação da Revista Anais de Enfermagem


Assuntos
Humanos , Feminino , Enfermeiras e Enfermeiros , História da Enfermagem , Escolas de Enfermagem , Sociedades
11.
Rev. bras. enfermagem ; 54(2): 253-260, abr.-jun. 2001.
Artigo em Português | HISA - História da Saúde | ID: his-11978

RESUMO

Estudo histórico social, cujo objetivo é descrever a trajetória de Zaíra Cintra Vidal, sua inserçäo na Escola de Enfermeiras Rachel Haddock Lobo e sua participaçäo na Associaçäo Brasileira de Enfermagem (ABEn). O estudo fundamenta-se nos conceitos de poder simbólico, habitus e luta simbólica de Pierre Bourdieu. As fontes primárias foram documentos existentes no Centro de Documentaçäo da EEAN/UFRJ e no Centro de Memória da FENF/UERJ. Os dados foram obtidos no período de agosto de 2000 a abril de 2001 mediante um roteiro de análise documental. Os resultados evidenciaram que Zaíra Cintra Vidal, nasceu em 05 de maio de 1903, graduou-se pela Escola de Enfermeiras do Departamento Nacional de Saúde Pública, em 1926; pós-graduou-se nos EUA de 1927 a 1929, retornando em 1943. Criou a Escola de Enfermeiras Rachel Haddock Lobo, sendo a primeira diretora por nove anos e participou na diretoria da ABEn e na redaçäo da Revista Anais de Enfermagem (AU)


Assuntos
História da Enfermagem , Enfermeiras e Enfermeiros , Sociedades , Escolas de Enfermagem
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