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1.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279251

RESUMO

Glucose transporter-4 (GLUT4) represents the major glucose transporter isoform responsible for glucose uptake into insulin-sensitive cells, primarily in skeletal muscle and adipose tissues. In insulin-resistant conditions, such as type 2 diabetes mellitus, GLUT4 expression and/or translocation to the cell plasma membrane is reduced, compromising cell energy metabolism. Therefore, the use of synthetic or naturally occurring molecules able to stimulate GLUT4 expression represents a good tool for alternative treatments of insulin resistance. The present study aimed to investigate the effects of essential oils (EOs) derived from Pinus spp. (P. nigra and P. radiata) and of their main terpenoid constituents (α- and ß-pinene) on the expression/translocation of GLUT4 in myoblast C2C12 murine cells. For this purpose, the chemical profiles of the EOs were first analyzed through gas chromatography-mass spectrometry (GC-MS). Cell viability was assessed by MTT assay, and GLUT4 expression/translocation was evaluated through RT-qPCR and flow cytometry analyses. The results showed that only the P. nigra essential oil (PnEO) and α-pinene can increase the transcription of the Glut4/Scl2a4 gene, resulting in a subsequent increase in the amount of GLUT4 produced and its plasma membrane localization. Moreover, the PnEO or α-pinene can induce Glut4 expression both during myogenesis and in myotubes. In summary, the PnEO and α-pinene emulate insulin's effect on the GLUT4 transporter expression and its translocation to the muscle cell surface.


Assuntos
Monoterpenos Bicíclicos , Diabetes Mellitus Tipo 2 , Óleos Voláteis , Camundongos , Animais , Insulina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Óleos Voláteis/farmacologia , Óleos Voláteis/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Insulina Regular Humana/farmacologia , Glucose/metabolismo
2.
Molecules ; 29(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38542941

RESUMO

Ursodeoxycholic acid (UDCA) and acetoacetate are natural compounds present in the human intestine and blood, respectively. A number of studies highlighted that besides their well-known primary biological roles, both compounds possess the ability to influence a variety of cellular processes involved in the etiology of various diseases. These reasons suggested the potential of acetoacetate-UDCA hybrids as possible therapeutic agents and prompted us to develop a synthetic strategy to selectively derivatize the hydroxyl groups of the bile acid with acetoacetyl moieties. 3α-acetoacetoxy UDCA was obtained (60% isolated yield) via the regioselective transesterification of methyl acetoacetate with UDCA promoted by the Candida antarctica lipase B (CAL-B). 3α,7ß-bis-acetoacetoxy UDCA was obtained instead by thermal condensation of methyl acetoacetate and UDCA (80% isolated yield). This bis-adduct was finally converted to the 7ß-acetoacetoxy UDCA (82% isolated yield) via CAL-B catalyzed regioselective alcoholysis of the ester group on the 3α position. In order to demonstrate the value of the above new hybrids as UDCA-based scaffolds, 3α-acetoacetoxy UDCA was subjected to multicomponent Biginelli reaction with benzaldehyde and urea to obtain the corresponding 4-phenyl-3,4-dihydropyrimidin-2-(1H)-one derivative in 65% isolated yield.


Assuntos
Acetoacetatos , Ácido Ursodesoxicólico , Humanos , Ácidos e Sais Biliares
3.
J Environ Manage ; 302(Pt A): 113969, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34715611

RESUMO

Seagrass meadows provide important and valuable ecosystem services. They are affected by several natural and human-induced stressors, but a combination of natural recovery and management actions have recently inverted the worldwide reduction. The main objectives of this study were to provide science-based knowledge on ecology and restoration, framed on environmental-related policies. By coupling the general guidelines with practical experience, obtained from sequential in situ experiments carried out for several months in a show-case study area, this study provides guidelines useful for restoration practitioners. A decision-making approach is proposed to answer the following questions: 1) What is the best Zostera noltei transplanting method? 2) What is the best technique to reduce the bioturbation activity of Arenicola spp.?, 3) Do bioturbation reduction techniques affect the survival rate of Z. noltei transplants?, and finally, 4) What are the key steps to maximize the success of a Z. noltei transplant and increase the species' resilience? Having a Portuguese coastal lagoon as show-case (Mira Channel, Ria de Aveiro), different transplant and restoration methodologies were tested (i.e. metal frames, nails, bamboo sticks, shoots inserted unanchored into the sediment, and intact units of sediment with seagrasses, named as SODs) to assure low environmental impact on donor meadows, high survival rate of transplanted shoots and the recovery of fragmented or lost meadows. Moreover, to potentially reverse a degraded Arenicola spp. colonized seagrass habitat, different types of natural membranes were tested. Results showed that the best transplanting method is the use of SODs as the self-facilitation process of Z. noltei is enhanced, while being the least invasive for the donor population. The use of a natural membrane can significantly decrease the bioturbation stress caused by Arenicola spp., with jute membrane being the best option, given its cost-handling-benefit trade-offs. Enhancing the success of seagrass restoration requires the implementation of effective measures by environmental restoration practitioners. We defined a three-step process to improve the resilience of Z. noltei. This stepwise approach consists on 1) Characterization of the donor population, 2) Identification of the constraints and implementation of measures to prevent them, and 3) Scale-up the restoration plan. The application of this stepwise approach in intertidal coastal and estuarine systems management will, therefore, facilitate the success of Z. noltei restoration plans.


Assuntos
Recuperação e Remediação Ambiental , Zosteraceae , Ecossistema , Humanos
4.
Molecules ; 25(15)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32708013

RESUMO

The present work focused on the use of high-silica commercial zeolites as sorbent media for pharmaceuticals in an aqueous matrix. As drug probes, ketoprofen, hydrochlorothiazide, and atenolol were selected, because of their occurrence in surface waters and effluents from wastewater treatment plants. Pharmaceuticals adsorption was evaluated for two Faujasite topology zeolites with Silica/Alumina Ratio 30 and 200. The selected zeolites were demonstrated to be efficient sorbents towards all investigated pharmaceuticals, thanks to their high saturation capacities (from 12 to 32% w/w) and binding constants. These results were corroborated by thermal and structural analyses, which revealed that adsorption occurred inside zeolite's porosities, causing lattice modifications. Finally, zeolites have been tested as a pre-concentration media in the dispersive-solid phase extraction procedure. Recoveries higher than 95% were gained for ketoprofen and hydrochlorothiazide and approximately 85% for atenolol, at conditions that promoted the dissolution of the neutral solute into a phase mainly organic. The results were obtained by using a short contact time (5 min) and reduced volume of extraction (500 µL), without halogenated solvents. These appealing features make the proposed procedure a cost and time saving method for sample enrichment as well as for the regeneration of exhausted sorbent, rather than the more energetically expensive thermal treatment.


Assuntos
Dióxido de Silício/química , Zeolitas/química , Adsorção , Atenolol/química , Hidroclorotiazida/química , Cetoprofeno/química , Porosidade , Extração em Fase Sólida , Solventes/química , Propriedades de Superfície , Água , Poluentes Químicos da Água/química
5.
Molecules ; 24(3)2019 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-30691170

RESUMO

The growing number of cyclotrons of different sizes installed in the territory has given a strong impulse to the production of conventional and emerging radionuclides for medical applications. In particular, the great advantage of using medical cyclotrons is the possibility to produce on-site, when needed (on-demand), with medical radionuclides of interest encouraging the personalized medicine approach. Radiometals satisfy the ideal characteristics that radionuclides should have for routine employment in nuclear medicine, especially since they have a robust chemistry suitable to synthetize stable in vivo radiopharmaceuticals with high radiochemical yields. In this letter several interdisciplinary aspects involved in the radiometals cyclotron production cycle are summarized focusing the attention on cyclotron production facilities, target material, and chemical processing available for medical applications. As an example, the current status and recent development in the production of the theranostic radionuclide scandium-47 have been reported.


Assuntos
Ciclotrons , Radioisótopos , Compostos Radiofarmacêuticos , Escândio , Humanos , Medicina Nuclear , Cintilografia
6.
Chemphyschem ; 19(17): 2208-2217, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29774636

RESUMO

The adsorption behavior of neodymium (Nd3+ ) and yttrium (Y3+ ) cations on synthetic FAU zeolite X in its sodium form (NaX) has been investigated by means of macroscopic (adsorption isotherm determination and thermal analysis) and microscopic measurements (including solid-state NMR spectroscopy and X-ray powder diffraction). The multidisciplinary study reveals some unexpected features. Firstly, adsorption constants of cations are not correlated to their ionic radii or hydration enthalpy. The adsorption constant of Y3+ on NaX was indeed about twice that of Nd3+ , which is the opposite of what could be expected based on the size of the cations. In addition, adsorption was accompanied by partial dealumination of the zeolite framework. The extent of dealumination changed depending on the exchanged cations, with the extent being more significant on the Nd-exchanged zeolite than on the Y-exchanged one. The most interesting finding of this study, however, is the presence of supramolecular clusters composed of water, Nd3+ , residual sodium ions, and extra-framework aluminum at the interface of Nd-exchanged zeolite. The hypothesis that these host-guest complexes are responsible of the significantly different behavior exhibited by NaX towards the adsorption/desorption of Nd3+ and Y3+ has been formulated.

7.
Anal Bioanal Chem ; 410(10): 2457-2465, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29340722

RESUMO

About ten years after their introduction to the market (happened in 2006), the so-called second generation superficially porous particles (SPPs) have undoubtedly become the benchmark as well as, very often, the preferred choice for many applications in liquid chromatography (LC), when high efficiency and fast separations are required. This trend has interested practically all kinds of separations, with the only exception of chiral chromatography (at least so far). The technology of production of base SPPs is advanced, relatively simple and widely available. The deep investigation of mass transfer mechanisms under reversed-phase (RP) and normal-phase (NP) conditions for achiral separations has shown the advantages in the use of these particles over their fully porous counterparts. In addition, it has been demonstrated that SPPs are extremely suitable for the preparation of efficient packed beds through slurry packing techniques. However, the research in this field is in continual evolution. In this article, some of the most advanced concepts and modern applications based on the use of SPPs, embracing in particular ultrafast chiral chromatography and the design of SPPs with engineered pore structures or very reduced particle diameter, are revised. We describe modern trends in these fields and focus on those aspect where further innovation and research will be required. Graphical Abstract Word cloud of cutting edge applications of superficially porous particles in liquid chromatography.

8.
Chem Biodivers ; 15(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29282856

RESUMO

New drugs would be beneficial to fight resistant HIV strains, in particular those capable of interfering with essential viral functions other than those targeted by highly active antiretroviral therapy drugs. Despite the central role played by Tat protein in HIV transcription, a search for vegetable extracts able to hamper this important viral function was never carried out. In this work, we evaluated the chemical composition and possible interference of essential oil from Thymus vulgaris, Cananga odorata, Cymbopogon citratus, and Rosmarinus officinalis with the Tat/TAR-RNA interaction and with Tat-induced HIV-1 LTR transcription. GC/MS Analysis demonstrated the biodiversity of herbal species translated into essential oils composed of different blends of terpenes. In all of them, 4 - 6 constituents represent from 81.63% to 95.19% of the total terpenes. Essential oils of Thymus vulgaris, Cymbopogon citratus, and Rosmarinus officinalis were active in interfering with Tat functions, encouraging further studies to identify single terpenes responsible for the antiviral activity. In view of the quite different composition of these essential oils, we concluded that their interference on Tat function depends on specific terpene or a characteristic blend.


Assuntos
Cymbopogon/química , HIV-1/efeitos dos fármacos , Óleos Voláteis/farmacologia , Rosmarinus/química , Thymus (Planta)/química , Produtos do Gene tat do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Conformação Molecular , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo
9.
Molecules ; 23(10)2018 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-30347852

RESUMO

Until less than 10 years ago, chiral separations were carried out with columns packed with 5 or 3 µ m fully porous particles (FPPs). Times to resolve enantiomeric mixtures were easily larger than 30 min, or so. Pushed especially by stringent requirements from medicinal and pharmaceutical industries, during the last years the field of chiral separations by liquid chromatography has undergone what can be defined a "true revolution". With the purpose of developing ever faster and efficient method of separations, indeed, very efficient particle formats, such as superficially porous particles (SPPs) or.


Assuntos
Cromatografia Líquida , Cromatografia com Fluido Supercrítico , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Humanos , Cinética , Compostos Fitoquímicos/química , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/uso terapêutico , Porosidade , Estereoisomerismo
10.
Fish Shellfish Immunol ; 39(2): 343-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24882018

RESUMO

The deep-sea hydrothermal vent mussel Bathymodiolus azoricus is a symbiont bearing bivalve that is found in great abundance at the Menez Gwen and Lucky Strike hydrothermal vent sites and in close vicinity of the Azores region near the Mid-Atlantic Ridge (MAR). The physiological relationships that vent mussels have developed with their physical and chemical environments are likely to influence global gene expression profiles providing thus the means to investigate distinct biological markers predicting the origin of Bathymodiolus sp. irrespectively of their geographical localization. Differences found at gene expression levels, and between fluorescence in situ hybridization (FISH) and 16S rRNA amplicon sequencing results provided experimental evidence for the distinction of both Menez Gwen and Lucky Strike vent mussel individuals based on bacterial and vent mussel gene expression signatures and on the constitutive distribution and relative abundance of endosymbiotic bacteria within gill tissues. Our results confirmed the presence of methanotroph endosymbionts in Menez Gwen vent mussels whereas Lucky Strike specimens seem to harbor a different bacterial morphotype when a methane monooxygenase gene specific probe was used. No qualitative differences could be visualized between Menez Gwen and Lucky Strike individuals when tested with a sulfur-oxidizing-related probe. Quantitative PCR (qPCR) studies revealed different gene expression profiles in both Menez Gwen and Lucky Strike mussel gill tissues for the immune genes selected. Genes encoding transcription factors presented noticeably low levels of fold expression whether in Menez Gwen or Lucky Strike animals whereas the genes encoding effector molecules appeared to have higher levels expression in gill tissues from Menez Gwen animals. The peptidoglycan recognition molecule encoding gene, PGRP, presented the highest level of transcriptional activity among the genes analyzed in Menez Gwen mussel gill tissues, seconded by carcinolectin and thus denoting the relevance of immune recognition molecules in early stage of the immune responses onset. Genes regarded as encoding molecules involved in signaling pathways were consistently expressed in both Menez Gwen and Lucky Strike mussel gill tissues. Remarkably, the immunity-related GTPase encoding gene demonstrated, in Lucky Strike samples, the highest level of expression among the signaling molecule encoding genes tested when expressions levels were compared between Menez Gwen and Lucky Strike animals. A differential expression analysis of bacterial genes between Menez Gwen and Lucky Strike mussels indicated a clear expression signature in the latter animal gill tissues. The bacterial community structure ensued from the 16S rRNA sequencing analyses pointed at an unpredicted conservation of endosymbiont bacterial loads between Menez Gwen and Lucky Strike samples. Taken together, our results support the hypothesis that B. azoricus exhibits different transcriptional statuses while living in distinct hydrothermal vent sites may result in distinct gene expressions because of physico-chemical and/or symbiont densities differences.


Assuntos
Bivalves/metabolismo , Bivalves/microbiologia , Ecossistema , Regulação da Expressão Gênica/fisiologia , Fontes Hidrotermais , Microbiota/genética , Simbiose , Animais , Oceano Atlântico , Sequência de Bases , Biologia Computacional , Primers do DNA/genética , Geografia , Brânquias/microbiologia , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Especificidade da Espécie , Transcriptoma
11.
J Hazard Mater ; 474: 134848, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850941

RESUMO

Finding time-efficient and cost-effective data collection methods is a challenge when addressing aquatic litter pollution on a global scale. In this study, we analysed data on aquatic benthic debris collected worldwide by volunteer scuba divers through the Dive Against Debris® citizen science initiative, examining its relationship with spatial and socio-economic factors. Plastic-dominated litter was found in both marine (64 %) and freshwater (48 %) environments, followed by metal and glass. Lower litter abundances have been recorded in high income countries such as in Europe, Central Asia and North America. Plastic fragments and fishing lines were the most abundant seafloor litter items, while takeaway containers (aluminium cans, glass bottles) were dominant in freshwater environments. Single-use plastics, including objects for food and beverage consumption, accounted for about 1/3 of the total benthic aquatic debris. Our findings highlight the need to prioritise the fishing industry and change our fast-paced modern lifestyle. Citizen science initiatives, once data cleanup is conducted to overcome any bias, can provide valuable tools for better understanding and quantifying marine litter pollution. The outcomes gained can be leveraged to improve consumer awareness and inform environmental policies aimed at addressing aquatic litter pollution more effectively.


Assuntos
Plásticos , Monitoramento Ambiental/métodos , Polímeros/química , Poluentes Químicos da Água/análise , Água Doce
12.
Artigo em Inglês | MEDLINE | ID: mdl-38460448

RESUMO

This work reports the characterization of the lipidic fraction of seven species of marine organisms gathered along the shoreline of the Po Delta Park of Emilia-Romagna Region (Italy) and of the north Adriatic Sea. Two species of oysters (Crassostrea gigas and Ostrea edulis), two species of clams (Chamelea gallina and Ruditapes philippinarum), one species of mussel (Mytilus galloprovincialis), one species of macroalgae (Ulva rigida), and one species of spiny dogfish (Squalus acanthias) were analyzed to characterize their fatty acids profile and related nutritional value. The lipid fraction was simultaneously extracted and transesterified into fatty acid methyl esters (FAMEs) by using a recently developed one-step microwave-assisted extraction/derivatization (MAED) method. The obtained FAMEs extract was analyzed by a rapid comprehensive multidimensional gas chromatography (GC × GC) method (30 min). The system was equipped with a reverse set of columns (polar × non-polar) connected through a reversed fill/flush flow modulator. The GC × GC system was coupled with a flame-ionization detector (FID) for both qualitative and quantitative purposes. The MAED- GC × GC-FID methodology was suitable in the context of samples containing high percentages of omega-3 PUFA. A total of 82 FAMEs were tentatively identified using standards, literature data, and the two-dimensional plot location. FAME profiles obtained with the proposed approach were comparable with reference methods (AOCS Ce 2b-11), showing no significant differences. Moreover, to determine the food nutritional value of the samples investigated, the most common nutritional indices (index of atherogenicity, index thrombogenicity, hypocholesterolemic/hypercholesterolemic ratio, health-promoting index, unsaturation index, and the fish lipid quality index) were calculated from FAME profiles. Among the samples investigated, Squalus acanthias presented the best nutritional score, while Ruditapes philippinarum had the worst score in 3 out of 6 indices.


Assuntos
Organismos Aquáticos , Algas Comestíveis , Ácidos Graxos , Ulva , Animais , Ácidos Graxos/análise , Ionização de Chama/métodos , Micro-Ondas , Cromatografia Gasosa/métodos
13.
Arch Environ Contam Toxicol ; 65(4): 642-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23846775

RESUMO

Trace element accumulation is particularly important in coastal and transitional environments, which act as contaminant buffers between the continental and marine systems. We compared trace element transfer to the biota in two locations with different open-sea exposures in a semi-enclosed marine coastal area (Stagnone di Marsala, Sicily, Italy) using isotopically reconstructed food chains. Samples of sediment, macroalgae, seagrasses, invertebrates, fish, and bird feathers were sampled in July 2006 and analysed for stable carbon and nitrogen isotopes (δ(13)C, δ(15)N) and trace elements (arsenic [As], cadmium [Cd], total mercury [THg], and lead [Pb]). Trophic magnification factors were calculated through the relationships between trace elements and δ(15)N in consumers. As and Pb were greater in organic matter sources (sediments and primary producers), whereas Cd and THg were greater in bird feathers. At the food chain level, an insignificant trophic transfer was found for all elements, suggesting biodilution rather than biomagnification. Sediments were more contaminated in the location with lower open-sea exposure. Macroalgae and seagrasses overall mirrored the spatial pattern highlighted in sediments, whereas differences between the two locations became further decreased moving toward higher trophic levels, indicating that trophic transfer of sediment and macrophyte-bound trace elements to the coastal lagoon food chain may be of relatively minor importance.


Assuntos
Monitoramento Ambiental , Cadeia Alimentar , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Isótopos de Carbono/análise , Plumas/química , Peixes/metabolismo , Sedimentos Geológicos/química , Invertebrados/metabolismo , Isótopos de Nitrogênio/análise , Poaceae/química , Alga Marinha/química , Sicília , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo
14.
PeerJ ; 11: e15162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37013142

RESUMO

Background: Hydrothermal vents, cold seeps, pockmarks and seamounts are widely distributed on the ocean floor. Over the last fifty years, the knowledge about these volcanic-associated marine ecosystems has notably increased, yet available information is still limited, scattered, and unsuitable to support decision-making processes for the conservation and management of the marine environment. Methods: Here we searched the Scopus database and the platform Web of Science to collect the scientific information available for these ecosystems in the Mediterranean Sea. The collected literature and the bio-geographic and population variables extracted are provided into a systematic map as an online tool that includes an updated database searchable through a user-friendly R-shiny app. Results: The 433 literature items with almost one thousand observations provided evidence of more than 100 different volcanic-associated marine ecosystem sites, mostly distributed in the shallow waters of the Mediterranean Sea. Less than 30% of these sites are currently included in protected or regulated areas. The updated database available in the R-shiny app is a tool that could guide the implementation of more effective protection measures for volcanic-associated marine ecosystems in the Mediterranean Sea within existing management instruments under the EU Habitats Directive. Moreover, the information provided in this study could aid policymakers in defining the priorities for the future protection measures needed to achieve the targets of the UN Agenda 2030.


Assuntos
Ecossistema , Fontes Hidrotermais , Mar Mediterrâneo , Biodiversidade , Bibliometria
15.
Int J Biol Macromol ; 253(Pt 5): 127145, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37778590

RESUMO

Marine environments represent an incredible source of biopolymers with potential biomedical applications. Recently, drug delivery studies have received great attention for the increasing need to improve site specificity, therapeutic value, and bioavailability, reducing off-target effects. Marine polymers, such as alginate, carrageenan, collagen, chitosan, and silica, have reported unique biochemical features, allowing an efficient binding with drugs, and a controlled release to the target tissue, also obtainable through "green processes". In the present review, we i) analysed the last ten years of scientific peer-reviewed literature; ii) divided the articles based on the achieved experimental phases, tagged as chemistry, drug release, and drug delivery, and iii) compared the best performances among marine polymers extracted from micro- and macro-organisms. Many reviews describe drug carriers from marine organisms, focusing on a single biopolymer or a chemical class. Our study is a groundbreaking literature collection, representing the first thorough investigation of all marine biopolymers described. Most articles report experimental results on the chemical characterisation of marine biopolymers and their in vitro behaviour as drug carriers, although development processes and commercial applications are still in the early stages. Hence, the next efforts should be focused on the sustainable production of marine polymers and final product development.


Assuntos
Sistemas de Liberação de Medicamentos , Dióxido de Silício , Sistemas de Liberação de Medicamentos/métodos , Polissacarídeos/química , Portadores de Fármacos/química , Biopolímeros/química , Polímeros/química , Proteínas , Lipídeos
16.
Stud Health Technol Inform ; 297: 304-311, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36073408

RESUMO

Mobility-as-a-Service and Demand-Responsive-Transport schemes are promoting progressively a user-centered approach, made of modularity, flexibility and tailor-made travel experience, and pandemic emergency has furthermore enhanced this new way of thinking, thus representing an unprecedented occasion to develop a new paradigm for a more sustainable and resilient transport system, thus ensuring a greater level of social and territorial inclusion beyond traditional urban borders and outdated distinctions of targeted services for particular users' categories. This paper discusses the main features of MaaS and DRT schemes in order to assess if they could be able to cope with Universal Design principles and to improve metropolitan accessibility accordingly to the urgent request for social and territorial inclusion as sustainable development pre-requisites, made by different stakeholders in the international and European debate (see UNO SDGs or EU Cork Declaration 2.0), and re-launched by many national initiatives (SNAI for Italy, Espana Vacìa for Spain…). To re-think metropolitan mobility as a service that can be shaped accordingly to user's needs and to redefine transport supply as a complex puzzle made by different and complementary services could represent a unique opportunity to overcome one of traditional public transport dramatic problems: low mobility demand, whether it be due to sparsely populated areas or connected with specific demands of targeted population categories. Hence this paper recalls some of the recent DRT experiences already active in Genova Metropolitan Area -the so-called DRINBUS above all- along with the on-demand mobility strategy for Ligurian internal areas in order to discuss how this new user-centered approach is acting on the marginalization of remote territories and fragile user categories. The choice to develop a MaaS scheme could re-shape metropolitan mobility as a comprehensive and global mosaic made by multiple pieces, thus making more resilient the entire system thanks to its modularity and redundancy. This allows to make more sustainable "niche" services as well, according to the systemic nature of this mobility platform, thus opposing the present unsuccessful approach of creating ad-hoc options, focusing indeed on the user's request to travel from point A to point B, without the need to define him as urban resident, commuter, disabled or not, towards a greater social inclusion and territorial cohesion.


Assuntos
Pessoas com Deficiência , Meios de Transporte , Humanos , Itália , Masculino , Espanha , Viagem
17.
Animals (Basel) ; 12(24)2022 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-36552419

RESUMO

This study is the first to assess the occurrence of micro-litter ingested by marine megafauna in the north-eastern Aegean Sea. A total of 25 specimens from four species of marine mammals, including dolphins and monk seals, and two species of sea turtles, found stranded along the coastline of Samos Island, Greece, were selected for the analysis. Litter particles, identified as microplastics (MPs), were ubiquitous throughout all sections of the gastrointestinal tract (oesophagus, stomach and intestine) in all specimens. Overall, the MPs most frequently found were black fibres 0.21-0.50 mm in size. These results provide insight into the extent of micro-litter ingestion and contamination in marine vertebrates. Here we propose a method of standardisation to establish a baseline for marine taxa in this region of the Mediterranean Sea, where knowledge of the topic is still lacking.

18.
Mar Environ Res ; 171: 105474, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34488069

RESUMO

Seagrass detritus can attract numerous invertebrates as it provides food and substrate within the meadow or in adjacent environments. Nonetheless, several factors could modify the invertebrate response to this habitat. In this study, we tested if epifaunal colonisation of Zostera noltei detritus was related to substrate availability rather than food and whether colonising assemblages were similar according to the meadow structural complexity. Litterbags filled with natural or artificial detritus were deployed within an eelgrass meadow in a Mediterranean coastal lagoon (Thau lagoon, France). Colonisation appeared to be driven by the presence of detritus, with similar assemblages in natural and artificial substrate, but with more individuals than the empty bags, used as controls. There were also no differences according to habitat complexity. These findings show that detritus, acting as a faunal magnet, plays an important role in maintaining biodiversity, as epifauna is a critical trophic link between primary producers and consumers.


Assuntos
Zosteraceae , Animais , Biodiversidade , Ecossistema , França , Humanos , Invertebrados
19.
Risk Anal ; 30(6): 952-61, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20199650

RESUMO

The intake of Cd, methyl-Hg, and Pb through consumption of black scabbardfish (BSF) (Aphanopus carbo) in Portugal as well as the associated probability of exceeding the respective provisional tolerable weekly intakes (PTWIs) was estimated. For this purpose, the contamination levels of heavy metals in this fish species were combined with constructed consumption scenarios or with a hypothesized consumption distribution. Whereas Cd and Pb posed no serious risk, the consumption of at least one portion of BSF per month as well as the hypothetical study in the Portuguese population produced nonnegligible probabilities of surpassing the PTWI for Me-Hg. Risk assessment for Portuguese consumers revealed a higher risk regarding Me-Hg, 1.19% and 1.81% with the plug-in (PI) and the tail estimation (TE) estimators, respectively. On the other hand, the risk for Cd and Pb was less than 1 in 100,000. TE was more realistic and accurate for Cd and Pb. Concerning Me-Hg, TE and PI estimators produced similar results. Furthermore, the limitations of a deterministic approach were shown.


Assuntos
Metais Pesados/toxicidade , Animais , Peixes , Portugal , Medição de Risco
20.
Environ Sci Pollut Res Int ; 27(27): 33649-33657, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32358755

RESUMO

It has been emphasized that seafood consumers may have a higher risk of mercury (Hg) exposure. Nevertheless, the co-occurrence of selenium (Se) in organisms may affect the toxicity and bioavailability of Hg. In this work, we aim to demonstrate the possible role of Se as a potential protective element against Hg in muscle and liver tissues of three demersal deep-sea fish species: common mora Mora moro, birdbeak dogfish Deania calcea, and smooth lanternshark Etmopterus pusillus. Comparing species, the birdbeak dogfish D. calcea showed the highest Hg concentrations, the lowest Se levels, the lowest mean Se:Hg molar ratio, a negative HBV-Se index, and no correlation between total length. On the other hand, smooth lanternshark E. pusillus showed the lowest Hg concentrations, the highest Se concentrations, the highest mean Se:Hg molar ratio, a positive HBV-Se index, and a significant positive correlation between total length and Se concentrations in muscle. Comparing tissues, the common mora Mora moro seems to accumulate more Hg and Se in liver than shark species D. calcea and E. pusillus that showed to accumulate Hg and Se preferentially in muscle. Our results indicate that these three species for having Hg concentrations near and above the EU regulatory thresholds and for presenting low Se:Hg ratios, and negative (or low positive) HBV-Se index may pose a real risk of Hg toxicity for the consumer.


Assuntos
Mercúrio/análise , Selênio , Poluentes Químicos da Água/análise , Animais , Peixes , Músculos/química , Alimentos Marinhos/análise
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