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1.
Neurol Sci ; 42(5): 1995-2003, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32997282

RESUMO

BACKGROUND: Fingolimod, an oral sphingosine 1-phosphate receptor modulator, is approved by EMA for relapsing-remitting multiple sclerosis (RRMS). OBJECTIVES: To assess the effectiveness and safety of fingolimod in patients with RRMS in real-world clinical practice in Portugal. METHODS: Retrospective, multicentre, non-interventional study, reporting 3 years follow-up of data collected from October 2015 to July 2016. Sociodemographic data and previous treatments at baseline and data regarding disease evolution, including number of relapses, annualised relapse rates (ARR) and Expanded Disability Status Scale (EDSS), were collected. RESULTS: Two-hundred and seventy-five participants were enrolled in the REALMS study. Results showed that the main reason to switch to fingolimod was failure of previous treatment (56.7%) and only 3.6% were naïve patients. In the total population, there was a significant decrease in ARR of 64.6% in the first year of treatment, 79.7% in the second year and 82.3% in the third year, compared with baseline. More than 67.0% of patients had no relapses during the 3 years after switching to fingolimod. EDSS remained stable throughout the study. CONCLUSIONS: Therapy with fingolimod showed a sustained effectiveness and safety over the 3 years, particularly on patients switched from first-line drugs (BRACE). No new safety issues were reported.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Cloridrato de Fingolimode/efeitos adversos , Humanos , Imunossupressores/efeitos adversos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Portugal/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento
2.
Med Oral Patol Oral Cir Bucal ; 26(5): e611-e618, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34162823

RESUMO

BACKGROUND: Implantoplasty (IP) involves polishing of the exposed surface of implants affected by peri-implantitis (PI). A study was made to determine whether the degree of bone loss influences the fracture resistance of implants with or without IP. MATERIAL AND METHODS: An in vitro study was carried out on 32 narrow (3.5 mm) dental implants with a rough surface and external hexagonal connection. Implantoplasty was performed in half of the implants of the sample. Both the IP and control implants were divided into two subgroups according to the amount of bone loss (3 mm or 7.5 mm). Standardized radiographic assessment of implant width was performed using specific software. The main outcome variable was the maximum compression force (Fmax) of implants when subjected to static resistance to fracture tests. Implant fractures were subsequently analyzed by scanning electron microscopy. A descriptive and bivariate analysis of the data was performed. RESULTS: Significant changes in implant width were observed after IP (p<0.05). No significant differences between IP and control implants were recorded in terms of the Fmax values in the two bone loss subgroups (3 mm: control 854.37N 195.08 vs. IP 752.12N 186.13; p=0.302, and 7.5 mm: control 548.82N 80.02 vs. IP 593.69N 111.07; p=0.370). Greater bone loss was associated to a decrease in Fmax, which proved significant for the control implants (p=0.001). Fractures were more frequently located in the platform (n=13). CONCLUSIONS: Implants with more apical bone levels appear to be more susceptible to fracture. On the other hand, IP does not seem to significantly decrease the fracture resistance of narrow (3.5 mm) platform dental implants with external hexagonal connections. The fact that most fractures occur in the platform area indicates that the latter is exposed to more mechanical stress.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Peri-Implantite , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Implantes Dentários/efeitos adversos , Humanos , Estresse Mecânico
3.
Phys Chem Chem Phys ; 22(24): 13418-13430, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32515438

RESUMO

The elementary steps of photocleavage in (coumarin-4-yl)methyl photoremovable protecting groups (PPGs) are elucidated by a combined electronic structure and time-resolved visible pump infrared probe (VIS-pump IR-probe) spectroscopic study. We specifically focus on the [7-(diethylamino)coumarin-4-yl]methyl (DEACM) PPG which has found increasing interest in biological applications over recent years. A series of leaving groups (LGs) are investigated, including azide (DEACM-N3), thiocyanate (DEACM-SCN), carbonate (DEACM-Carb), and a thymine nucleobase (DEACM-T) representing a model system for caged DNA. These systems are found to exhibit vastly different photocleavage time scales, ranging from the subpicosecond scale in the case of DEACM-SCN to ∼35 picoseconds in the case of DEACM-N3 and ∼540 picoseconds in the case of DEACM-Carb. In the case of DEACM-SCN, the appearance of the product is biphasic, with a fast (

4.
Ecotoxicol Environ Saf ; 164: 100-108, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30098505

RESUMO

Oxytetracycline (OTC) is a tetracycline antibiotic, widely used in human and veterinary medicines, including in aquaculture. Given this use, OTC has been detected in different aquatic environments. Some recent works have demonstrated unintentional biological activity of OTC in non-target aquatic organisms. This study investigated the acute and chronic effects of OTC on the physiology of the fish species Oncorhynchus mykiss (rainbow trout), namely through the quantification of the activity of enzymes involved in different biochemical pathways, such as detoxification (phase II - glutathione S-transferases - GSTs, uridine-diphosphate-glucuronosyltransferases - UGTs), neurotransmission (acetylcholinesterase - AChE) and energy production (lactate dehydrogenase - LDH). The here-obtained data demonstrated the induction of GSTs activity in gills, and inhibition of AChE activity in eyes tissue, in chronically exposed organisms, as well as alterations in LDH activity following both exposures. Considering this set of results, we can infer that OTC exposure may have induced the glutathione pathway of detoxification in gills with the involvement of GSTs, or indirectly due to the metabolites that may have been produced. In turn, these metabolites may have interfered with the mechanism of neurotransmission, also causing physiological and biochemical disturbances in rainbow trout after OTC exposure, namely disturbances in energetic metabolism. In addition, it is important to stress that such occurrences took place at low, environmentally realistic levels of OTC, suggesting that organisms exposed in the wild may be putative targets of toxic effects by commonly used drugs such as antibiotics.


Assuntos
Antibacterianos/toxicidade , Exposição Ambiental/efeitos adversos , Oncorhynchus mykiss/metabolismo , Oxitetraciclina/toxicidade , Transmissão Sináptica/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Animais , Biomarcadores , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glucuronosiltransferase/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , L-Lactato Desidrogenase/metabolismo , Qualidade da Água
5.
Phys Chem Chem Phys ; 19(9): 6487-6496, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28197598

RESUMO

The light-induced ultrafast uncaging process of the [7-(diethylamino)coumarin-4-yl]methyl (DEACM) cage is measured by time-resolved visible-pump-infrared-probe spectroscopy, and supported by steady-state absorption spectroscopy in the visible and infrared spectral regions. Understanding the uncaging process is important because its favorable properties make DEACM an interesting case for chemical and biological applications. It has a convenient absorption in the visible spectral range, and is relatively easily modified to carry leaving groups (LGs) such as nucleotides, substrates or inhibitors, which are inactive when bound and active when released. Previous work suggested a lower limit for the uncaging rate, which places it among the fastest available cages. Here, we determine the photodissociation directly to occur on the picosecond time scale by monitoring the appearance of the released LG in the infrared spectral region. In the present study, azide (N3) is chosen as an LG to monitor photodissociation because its vibrational mode is spectrally isolated (hence easy to follow) and its absorption wavenumber is sensitive to local structural rearrangements. The uncaging process is recorded up to 3 nanoseconds and compared to the collected steady-state spectra. The free LG appears on a picosecond time scale, rendering this one of the fastest known cages. No evidence is found for a tight-ion pair (TIP) preceding the free LG. The uncaging mechanism is found to be slowed down upon the addition of water to acetonitrile.

7.
J Fish Biol ; 88(5): 1796-810, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27020945

RESUMO

Sixty Centropomus parallelus juveniles were collected in March 2013 in two locations (Tromomó and Guaraguaçu) inside the Paranaguá estuarine complex, southern Brazil. The habitat residency and movement patterns of the individuals were inferred from Sr:Ca ratios and age recorded in the otoliths. Data suggest that the species spawns preferentially in brackish areas mainly from October to January, and that growth rate during the early juvenile stage could be influenced by environmental salinity. Furthermore, the data also show that C. parallelus can occupy diverse salinity habitats and migrate among marine, brackish and freshwater areas within the Paranaguá estuarine complex, showing a high environmental plasticity and adaptation.


Assuntos
Distribuição Animal , Ecossistema , Peixes/fisiologia , Animais , Brasil , Peixes/crescimento & desenvolvimento , Água Doce , Internato e Residência , Salinidade
8.
J Helminthol ; 90(4): 410-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26121918

RESUMO

Blue jack mackerel, Trachurus picturatus, is a carangid fish which constitutes an important commercial resource in the north-east Atlantic. Its metazoan parasite community from Portuguese mainland waters was investigated here for the first time. Nine parasite taxa were found, most of which are common parasites of Trachurus spp. The parasite community was broadly similar to that of the Atlantic horse mackerel, T. trachurus, from the same region, but two digenean species were detected in blue jack mackerel, Monascus filiformis and Tergestia sp., which did not occur in horse mackerel from this region. A comparison with the two previous studies of T. picturatus parasite communities shows that continental-shelf regions are characterized by higher prevalences of digenean trematodes and an absence of trypanorhynch cestodes, in contrast with oceanic regions.


Assuntos
Biodiversidade , Doenças dos Peixes/parasitologia , Parasitos/classificação , Parasitos/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Perciformes/parasitologia , Animais , Portugal , Água
9.
Lett Appl Microbiol ; 60(3): 288-97, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25443157

RESUMO

UNLABELLED: The aim of this study was to investigate the presence and the phenotypic expression of a gene coding for a putative collagenase. This gene (AHA_0517) was identified in Aeromonas hydrophila ATCC 7966 genome and named colAh. We constructed and characterized an Aeromonas piscicola AH-3::colAh knockout mutant. Collagenolytic activity of the wild-type and mutant strains was determined, demonstrating that colAh encodes for a collagenase. ColAh-collagen interaction was assayed by Far-Western blot, and cytopathic effects were investigated in Vero cells. We demonstrated that ColAh is a gluzincin metallopeptidase (approx. 100 kDa), able to cleave and physically interact with collagen, that contributes for Aeromonas collagenolytic activity and cytotoxicity. ColAh possess the consensus HEXXH sequence and a glutamic acid as the third zinc binding positioned downstream the HEXXH motif, but has low sequence similarity and distinct domain architecture to the well-known clostridial collagenases. In addition, these results highlight the importance of exploring new microbial collagenases that may have significant relevance for the health and biotechnological industries. SIGNIFICANCE AND IMPACT OF THE STUDY: Collagenases play a central role in processes where collagen digestion is needed, for example host invasion by pathogenic micro-organisms. We identified a new collagenase from Aeromonas using an integrated in silico/in vitro strategy. This enzyme is able to bind and cleave collagen, contributes for AH-3 cytotoxicity and shares low similarity with known bacterial collagenases. This is the first report of an enzyme belonging to the gluzincin subfamily of the M9 family of peptidases in Aeromonas. This study increases the current knowledge on collagenolytic enzymes bringing new perspectives for biotechnology/medical purposes.


Assuntos
Aeromonas hydrophila/enzimologia , Colágeno/metabolismo , Colagenase Microbiana/genética , Colagenase Microbiana/metabolismo , Aeromonas hydrophila/genética , Aeromonas hydrophila/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Chlorocebus aethiops , Clostridium/enzimologia , Clostridium/metabolismo , DNA Bacteriano/genética , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Análise de Sequência de DNA , Células Vero
10.
Ecotoxicology ; 24(9): 1896-905, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26298705

RESUMO

Currently diverse biocidal agents can be used for distinct applications, such as personal hygiene, disinfection, antiparasitic activity, and antifouling effects. Zinc pyrithione is an organometallic biocide, with bactericidal, algicidal and fungicidal activities. It has been recently incorporated in antifouling formulas, such as paints, which prevent the establishment of a biofilm on surfaces exposed to the aquatic environment. It has also been used in cosmetics, such as anti-dandruff shampoos and soaps. Previously reported data has shown the presence of this substance in the aquatic compartment, a factor contributing to the potential exertion of toxic effects, and there is also evidence that photodegradation products of zinc pyrithione were involved in neurotoxic effects, namely by inhibiting cholinesterases in fish species. Additional evidence points to the involvement of zinc pyrithione in alterations of metal homeostasis and oxidative stress, in both aquatic organisms and human cell models. The present work assesses the potential ecotoxicity elicited by zinc pyrithione in the freshwater fish Gambusia holbrooki after an acute (96 h) exposure. The oxidative stress was assessed by the quantification of the activities of specific enzymes from the antioxidant defense system, such as catalase, and glutathione-S-transferases; and the extent of peroxidative damage was quantified by measuring the thiobarbituric acid reactive substances levels. Neurotoxicity was assessed through measurement of acetylcholinesterase activity; and a standardized method for the description and assessment of histological changes in liver and gills of was also used. Zinc pyrithione caused non-specific and reversible tissue alterations, both in liver and gills of exposed organisms. However, histopathological indices were not significantly different from the control group. In terms of oxidative stress biomarkers, none of the tested biomarkers indicated the occurrence of pro-oxidative effects, suggesting that the oxidative pathway is not the major toxicological outcome of exposure to zinc pyrithione.


Assuntos
Ciprinodontiformes/metabolismo , Compostos Organometálicos/toxicidade , Piridinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Feminino , Masculino , Estresse Oxidativo/efeitos dos fármacos
11.
Arch Environ Contam Toxicol ; 68(2): 371-81, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25475590

RESUMO

A large body of evidence was compiled in the recent decades showing a noteworthy increase in the detection of pharmaceutical drugs in aquatic ecosystems. Due to its ubiquitous presence, chemical nature, and practical purpose, this type of contaminant can exert toxic effects in nontarget organisms. Exposure to pharmaceutical drugs can result in adaptive alterations, such as changes in tissues, or in key homeostatic mechanisms, such as antioxidant mechanisms, biochemical/physiological pathways, and cellular damage. These alterations can be monitored to determine the impact of these compounds on exposed aquatic organisms. Among pharmaceutical drugs in the environment, antibiotics are particularly important because they include a variety of substances widely used in medical and veterinary practice, livestock production, and aquaculture. This wide use constitutes a decisive factor contributing for their frequent detection in the aquatic environment. Tetracyclines are the individual antibiotic subclass with the second highest frequency of detection in environmental matrices. The characterization of the potential ecotoxicological effects of tetracycline is a much-required task; to attain this objective, the present study assessed the acute toxic effects of tetracycline in the freshwater fish species Gambusia holbrooki by the determination of histological changes in the gills and liver, changes in antioxidant defense [glutathione S-transferase (GST), catalase (CAT), and lipoperoxidative damage] as well as potential neurotoxicity (acetylcholinesterase activity). The obtained results suggest the existence of a cause-and-effect relationship between the exposure to tetracycline and histological alterations (more specifically in gills) and enzymatic activity (particularly the enzyme CAT in liver and GST in gills) indicating that this compound can exert a pro-oxidative activity.


Assuntos
Antibacterianos/toxicidade , Tetraciclina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Ciprinodontiformes/metabolismo , Água Doce/química , Glutationa Transferase/metabolismo
12.
J Econ Entomol ; 107(1): 144-53, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24665696

RESUMO

The combination of essential oils and Bacillus thuringiensis Berliner may represent an interesting control strategy. Thus, the study tested the following hypothesis: the combination of long pepper oil (Piper hispidinervum L.) and clove (Syzygium aromaticum L.) oils in two concentrations with Xentari WG (Bta) yields a more effective control of Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) affecting biological and reproductive parameters and leading to changes in the levels of phenoloxidase and nitric oxide in the hemolymph of the pest. The results demonstrate that only long pepper oil, at the highest concentration with Xentari WG (Bta), promotes reduced larval survival. However, both oils with or without the insecticide interfere in the biology and humoral immunity of S.frugiperda. All treatments caused a decrease in the amount of eggs, except for the clove oil at both concentrations without Bta. Therefore, the use of these oils is a promising alternative for the integrated management of S. frugiperda; however, its association with Bta demonstrated no significant increase in their efficiency.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Óleos Voláteis/toxicidade , Piper/química , Syzygium/química , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias , Endotoxinas , Fertilidade/efeitos dos fármacos , Hemolinfa/metabolismo , Proteínas Hemolisinas , Inseticidas , Monofenol Mono-Oxigenase/metabolismo , Mariposas/enzimologia , Mariposas/crescimento & desenvolvimento , Óxido Nítrico/metabolismo , Óleos Voláteis/química
13.
ScientificWorldJournal ; 2014: 170187, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24574867

RESUMO

In the present study, core-reinforced braided composite rods (BCRs) were developed and characterized for strain sensing capability. A mixture of carbon and glass fibre was used in the core, which was surrounded by a braided cover of polyester fibres. Three compositions of core with different carbon fibre/glass fibre weight ratios (23/77, 47/53, and 100/0) were studied to find out the optimum composition for both strain sensitivity and mechanical performance. The influence of carbon fibre positioning in BCR cross-section on the strain sensing behaviour was also investigated. Strain sensing property of BCRs was characterized by measuring the change in electrical resistance with flexural strain. It was observed that BCRs exhibited increase (positive response) or decrease (negative response) in electrical resistance depending on carbon fibre positioning. The BCR with lowest amount of carbon fibre was found to give the best strain sensitivity as well as the highest tensile strength and breaking extension. The developed BCRs showed reversible strain sensing behaviour under cyclic flexural loading with a maximum gauge factor of 23.4 at very low strain level (0.55%). Concrete beams reinforced with the optimum BCR (23/77) also exhibited strain sensing under cyclic flexural strain, although the piezoresistive behaviour in this case was irreversible.


Assuntos
Carbono , Materiais de Construção , Vidro , Estresse Mecânico , Fibra de Carbono , Indústria da Construção/instrumentação , Indústria da Construção/métodos , Suporte de Carga
14.
J Fish Biol ; 84(4): 1234-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24588781

RESUMO

To assess the periodicity of micro-increment formation in otoliths of Lipophrys pholis, 90 early juveniles were immersed in alizarin red S or tetracycline hydrochloride for 24 h and sacrificed after 10, 20 and 30 days. The number of micro-increments viewed under light microscopy was significantly related to the duration of the experimental period, and the slopes of the linear regressions were not significantly different from 1. This study indicates that micro-increments in sagittae were deposited daily and can be used as reliable sources of age information for L. pholis.


Assuntos
Peixes/anatomia & histologia , Membrana dos Otólitos/anatomia & histologia , Animais , Antraquinonas , Corantes Fluorescentes , Modelos Lineares , Tetraciclina
15.
Acta Ortop Mex ; 38(1): 57-59, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38657153

RESUMO

Acute calcific periarthritis (ACP) in the interphalangeal joints of the hand is rare, with less than 100 cases reported. A rare case of ACP in a proximal interphalangeal (PIP) joint of the hand, in a young black woman, after acute trauma, is presented. She experienced severe pain and limited range of motion, and was medicated with an oral corticoid, which was followed by a rapid resolution of the symptoms. At six months, there were no signs of clinical or radiographic recurrence. Recognition of ACP allows for avoiding unnecessary treatments. In this case, treatment with corticoids might have played a role in a faster recovery.


La periartritis calcificada aguda (PCA) en las articulaciones interfalángicas de la mano es rara, con menos de 100 casos reportados. Se presenta un caso raro de PCA en una articulación interfalángica proximal (IFP) de la mano, en una mujer joven de raza negra, después de un traumatismo agudo. Experimentó dolor intenso y rango de movimiento limitado, y fue medicada con un corticoide oral, lo que fue seguido por una rápida resolución de los síntomas. A los seis meses no hubo signos de recurrencia clínica ni radiológica. El reconocimiento de PCA permite evitar tratamientos innecesarios. En este caso, el tratamiento con corticoides podría haber contribuido a una recuperación más rápida.


Assuntos
Calcinose , Articulações dos Dedos , Periartrite , Humanos , Feminino , Calcinose/etiologia , Doença Aguda , Traumatismos dos Dedos , Adulto
16.
Int J Pharm ; 664: 124631, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39182742

RESUMO

Epilepsy is a highly prevalent neurological disease and valproic acid (VPA) is used as a first-line chronic treatment. However, this drug has poor oral bioavailability, which requires the administration of high doses, resulting in adverse effects. Alternative routes of VPA administration have therefore been investigated, such as the nose-to-brain route, which allows the drug to be transported directly from the nasal cavity to the brain. Here, the use of nanostructured lipid carriers (NLC) to encapsulate drugs administered in the nasal cavity has proved advantageous. The aim of this work was to optimise a mucoadhesive formulation of VPA-loaded NLC for intranasal administration to improve the treatment of epilepsy. The Design of Experiment (DoE) was used to optimise the formulation, starting with component optimisation using Mixture Design (MD), followed by optimisation of the manufacturing process parameters using Central Composite Design (CCD). The optimised VPA-loaded NLC had a particle size of 76.1 ± 2.8 nm, a polydispersity index of 0.190 ± 0.027, a zeta potential of 28.1 ± 2.0 mV and an encapsulation efficiency of 85.4 ± 0.8%. The in vitro release study showed VPA release from the NLC of 50 % after 6 h and 100 % after 24 h. The in vitro biocompatibility experiments in various cell lines have shown that the optimised VPA-loaded NLC formulation is safe up to 75 µg/mL, in neuronal (SH-SY5Y), nasal (RPMI 2650) and hepatic (HepG2) cells. Finally, the interaction of the optimised VPA-loaded NLC formulation with nasal mucus was investigated and mucoadhesive properties were observed. The results of this study suggest that the use of intranasal VPA-loaded NLC may be a promising alternative to promote VPA targeting to the brain, thereby improving bioavailability and minimising adverse effects.


Assuntos
Administração Intranasal , Anticonvulsivantes , Encéfalo , Portadores de Fármacos , Lipídeos , Nanoestruturas , Mucosa Nasal , Ácido Valproico , Ácido Valproico/administração & dosagem , Ácido Valproico/farmacocinética , Ácido Valproico/química , Portadores de Fármacos/química , Lipídeos/química , Humanos , Mucosa Nasal/metabolismo , Mucosa Nasal/efeitos dos fármacos , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/química , Nanoestruturas/química , Nanoestruturas/administração & dosagem , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Liberação Controlada de Fármacos , Tamanho da Partícula , Adesividade , Animais , Sobrevivência Celular/efeitos dos fármacos
17.
Sci Rep ; 14(1): 7479, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553528

RESUMO

Maneuvering a spacecraft in the cislunar space is a complex problem, since it is highly perturbed by the gravitational influence of both the Earth and the Moon, and possibly also the Sun. Trajectories minimizing the needed fuel are generally preferred in order to decrease the mass of the payload. A classical method to constrain maneuvers is mathematically modeling them using the Two Point Boundary Value Problem (TPBVP), defining spacecraft positions at the start and end of the trajectory. Solutions to this problem can then be obtained with optimization techniques like the nonlinear least squares conjugated with the Theory of Functional Connections (TFC) to embed the constraints, which recently became an effective method for deducing orbit transfers. In this paper, we propose a tangential velocity (TV) type of constraints to design orbital maneuvers. We show that the technique presented in this paper can be used to transfer a spacecraft (e.g. from the Earth to the Moon) and perform gravity assist maneuvers (e.g. a swing-by with the Moon). In comparison with the TPBVP, solving the TV constraints via TFC offers several advantages, leading to a significant reduction in computational time. Hence, it proves to be an efficient technique to design these maneuvers.

18.
Plant Dis ; 97(4): 560, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30722251

RESUMO

Quercus robur L., commonly known as "pedunculate oak," is a long-lived deciduous tree native to most of Europe. It is of great ecological and forestry importance. It is also commonly cultivated as an ornamental tree in parks and gardens. Since 2009 and most likely related to increased drought periods, diseased ornamental trees have been observed in the campus of the University of Aveiro, Portugal. More than 50% of the trees are already damaged by the disease. The symptoms included twig and branch dieback and sunken necrotic bark lesions that could progress to the trunk, resulting in the death of large sections of the tree. Ascomata and conidiomata typical of Botryosphaeriaceae were observed on branches of symptomatic trees. Ascospores were hyaline, aseptate, ovoid to fusoid, and conidia were hyaline, aseptate, smooth, thin-walled, and fusiform with base truncate. Single spore isolates were obtained from samples. In culture, single ascospore isolates produced conidia similar to the ones found on the host. Diseased branch tissues were surface sterilized with 5% NaOCl, plated on potato dextrose agar (PDA), and incubated at 25°C. Fungal isolates recovered produced white aerial mycelium that darkened with age becoming grey to dark grey and conidia that were similar in all aspects to the ones produced by single spore isolates. All isolates produced on PDA a yellow pigment that diffused into the agar and disappeared after 6 to 7 days. Morphological and cultural aspects of the isolates were similar to the species Neofusicoccum luteum (Pennycook & Samuels) Crous, Slippers & A.J.L. Phillips and N. australe (Slippers, Crous & M.J. Wingf.) Crous, Slippers & A.J.L. Phillips (2). Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR fingerprinting divided the isolates into two groups (1). Two isolates (CAA352 and CAA392), one from each group, were selected for further identification by sequencing of the internal transcribed spacer (ITS) region of the rDNA and part of the elongation factor 1-alpha gene (EF1-α) (Accession No. ITS: JX975212 JX975213; EF1-α: JX975210 JX975211). BLAST analysis showed that ITS and EF1-α sequences from group 1 and 2 had 99 to 100% similarity to reference cultures (including ex-type) of N. luteum and N. australe, respectively. To confirm pathogenicity and fulfill Koch's postulates, six 2-year-old seedlings of Q. robur were artificially infected with isolates CAA352 and CAA392 and kept at approximately 20 to 25°C. A shallow wound was done with a scalpel on the basal part of the stem of each seedling, a bark portion was removed aseptically and a PDA disc (0.5 cm) of an actively growing culture was placed on the wound. Control seedlings received sterile PDA discs. The inoculation site was wrapped in Parafilm to prevent desiccation. Within 8 weeks, infected seedlings developed canker lesions associated with vascular necrosis around the inoculation point. A third of the seedlings died and developed abundant pycnidia on the stem. Control seedlings remained symptomless. Both pathogens were successfully reisolated from the infected tissue. N. luteum and N. australe are increasingly reported as causing diseases to a wide range of woody hosts of economic and forestry importance (3). To our knowledge, this is the first report of both species causing dieback and canker disease on Q. robur. References: (1) A. Alves et al. Res. Microbiol. 158:112, 2007. (2) P. W. Crous et al. Stud. Mycol. 55:235, 2006. (3) B. Slippers et al. Fungal Biol. Rev. 21:90, 2007.

19.
Eur J Prosthodont Restor Dent ; 21(3): 127-34, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24261105

RESUMO

The aim of this study was to investigate the current guidelines used for the undergraduate course subject Removable Partial Denture in Portuguese Dental Schools following the Bologna Process. All Dental Schools were sent a questionnaire, divided into the following areas: (I) organization and syllabus; (II) teaching methods; (III) materials and techniques; Answers about organization and syllabus of course subjects showed the most variability; teaching methods were identical regarding principal textbook and live demonstrations of laboratory/clinical procedures; the same techniques and materials are used in all the schools' dental clinics. The majority of Dental Schools present similar guidelines for removable partial dentures.


Assuntos
Planejamento de Dentadura , Prótese Parcial Removível , Educação em Odontologia , Prostodontia/educação , Currículo , Educação em Odontologia/métodos , Humanos , Portugal , Faculdades de Odontologia , Inquéritos e Questionários
20.
SAR QSAR Environ Res ; 34(12): 1023-1039, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38047444

RESUMO

A study of Quantitative Structure Activity Relationship (QSAR) was performed to assess the possible adverse effects of 25 pharmaceuticals commonly found in the Brazilian water compartments and to establish a ranking of environmental concern. The occurrence (O), the persistence (P), the mobility (M), and the toxicity (T) of these compounds in the Brazilian drinking water reservoirs were evaluated. Moreover, to verify the predicted OPMT dataset outcomes, a quality index (QI) was also developed and applied. The main results showed that: (i) after in silico predictions through VEGA QSAR, 19 from 25 pharmaceuticals consumed in Brazil were classified as persistent; (ii) moreover, after in silico predictions through OPERA QSAR, 15 among those 19 compounds considered persistent, were also classified as mobile or very mobile. On the other hand, the results of toxicity indicate that only 9 pharmaceuticals were classified with the highest toxicity level. Ultimately, the QI of 7 from 25 pharmaceuticals were categorized as 'optimal'; 15 pharmaceuticals were categorized as 'good'; and only 3 pharmaceuticals were categorized as 'regular'. Therefore, based on the QI criteria used, it is possible to assume that this OPMT prediction dataset had a good reliability. Efforts to reduce emissions of OPMT-pharmaceuticals in Brazilian drinking water reservoirs are encouraged.


Assuntos
Água Potável , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Brasil , Reprodutibilidade dos Testes , Relação Quantitativa Estrutura-Atividade , Preparações Farmacêuticas , Medição de Risco
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