36 research outputs found
Assessment of the antidiabetic activity of flavonoids: targeting key enzymes involved in type 2 diabetes pathophysiology
A mulher idosa institucionalizada: Saúde mental e bem-estar espiritual
Dissertação de Mestrado em Psicologia ClÃnica apresentada ao ISPA - Instituto UniversitárioO envelhecimento é uma etapa da vida que permanece pouco conhecida e estudada, se comparada a outras fases do desenvolvimento humano. Nesta pesquisa procurou-se explorar a relação entre eventuais alterações psicológicas em mulheres idosas, e o seu bem-estar espiritual. Participaram neste estudo 30 mulheres, idosas, institucionalizadas, a quem foi aplicado o MMSE (Mini Mental State Examination) para detectar disfunções cognitivas, o MMPI-2 (Minnesota Multiphasic Personality Inventory -2) para identificar perfis de personalidade e por fim o SWBQ (Versão Portuguesa do Questionário de Bem-Estar Espiritual) para classificar o nÃvel de bem-estar espiritual das participantes. Entre os resultados salienta-se a não existência de declÃnio cognitivo e valores acima dos parâmetros normais nas escalas de bem-estar e mini-mult, observando-se neste último uma maior incidência de sintomas ansiosos e depressivos, em relação à s outras perturbações. Verificaram-se também relações significativas entre algumas dimensões das diferentes escalas utilizadas (nomeadamente entre as dimensões depressão, psicopatia e a dimensão pessoal do SWBQ) entre estas e alguns dados socio-demográficos. Entre as implicações destes resultados pensa-se ser importante a existência de mais estudos para compreender melhor a relação entre espiritualidade e saúde mental.ABSTRACT: Aging is a stage of life that remains little known and studied, compared to other phases of human development. This research sought to explore the possible relationship between psychological changes in older women, and their spiritual welfare. 30 women participated in this study, elderly, institutionalized, who were assessed with the MMSE (Mini Mental State Examination) to detect cognitive disorders, the MMPI - 2 (Minnesota Multiphasic Personality Inventory -2) to identify personality profiles and finally the SWBQ (Portuguese version of the Spiritual Well-being Questionnaire) to rate the level of spiritual well - being of participants. Among the findings highlight the absence of cognitive decline and values above the normal range in the scales of well -being and mini-mult, observing the latter a higher incidence of anxiety and depressive symptoms in relation to other disturbances. There were also significant relationships between some dimensions of the different scales used (particularly between dimensions depression, psychopathy and the personal dimension of the spiritual well -being questionnaire) between these and some socio - demographic data. Among the implications of these results are thought to be important to have more studies to better understand the relationship between spirituality and mental health
Synthesis and in vitro α-glucosidase inhibitory activity of polyhydroxylated 2-styrylchromones
2-Styrylchromones (2-SC) are a small class of naturally-occurring oxygen-containing heterocycles. Although
they are scarce in nature, a large number of 2-SC derivatives has been synthesized and their biological activ ity
evaluated, namely as antiallergic, anti-inflammatory, antimicrobial, antioxidant and antitumor agents [l]. As far
as we know, the antidiabetic activity of 2-SC is still unexplored. With this rational in mind, a series of 12
polyhydroxylated derivatives of 2-SC (1) were synthethized and used as inhibitors of the carbohydrate
hydrolyzing enzyme a-glucosidase. This enzyme catalyzes the final step of the digestive process of starch and
break down oligosaccharides to monosaccharides being one of the most currently used therapeutic approaches to
decrease postprandial hyperglycemia and consequently to control type 2 diabetes mellitus [2].
The synthesis of polyhydroxylated 2-SC involves a multi-step strategy starting with the condensation of the
appropriate 2'-hydroxyacetophenones with cinnamic acid derivatives, base-promoted Baker- Yenkataraman
rearrangement of the esters formed, cyclodehydration and finnaly cleavage of the protecting groups to afford the
desired polyhydroxylated 2-SC (3]. The in vitro assay to evaluate the inhibitory activity of the compounds under
study and the positive control, acarbose, against a-glucosidase was performed by monitoring the hydrolysis of
the substrate p-nitrophenyl glucopyranoside into the product p-nitrophenol at 405 nm. In addition, the study of
the inhibition type was carried out through nonlinear regression Michaelis-Menton enzymatic kinetics and the
corresponding Lineweaver-Burk plot [4].This work received financial support from the European Union (FEDER funds
POCI/01 /0145/FEDER/007265) and National Funds (FCT/MEC, Fundayiio para a Ciencia e Tecnologia and
Ministerio da Educação e Ciência) under the Partnership Agreement PT2020 UID/ AGR/00690/2013;
UID/QUI/50006/2013; UID/QUI/00062/2019, and "Programa Operacional Competitividade e
Intemacionalizayiio" (COMPETE) (POCI-01-0145-FEDER-029241), and under the framework of QREN
(NORTE-01-0145-FEDER-000024).info:eu-repo/semantics/publishedVersio
Inhibition of the carbohydrate-hydrolyzing enzymes α-amylase and α-glucosidase by hydroxylated xanthones
Xanthones are oxygen-containing heterocyclic compounds that exhibit a wide range of biological and
pharmacological properties. Some natural and synthetic derivatives have been identified for their antidiabetic
profile, mainly as α-glucosidase inhibitors. However, studies concerning the inhibition of both
carbohydrate-hydrolyzing enzymes α-amylase and α-glucosidase are scarce. Thus, in order to identify
some of these dual-target antidiabetic agents, a series of new synthetic xanthones were evaluated
together with their commercial parents mangiferin (4), α-mangostin (5) and γ-mangostin (6). The results
showed that xanthones exhibited a systematic stronger inhibition against α-glucosidase rather than for
α-amylase. Derivatives 2c, 3a and 3b, bearing one catechol moiety, were the most active inhibitors of
α-amylase, while xanthones 2c, 3b and 3c were the most active against α-glucosidase activity, with IC50
values lower than 10 μM. These findings suggest that the substitution pattern of the xanthone scaffold
modulated the inhibitory activity of these compounds, and some structure–activity relationships could be
established for both assays. In addition, the type of inhibition was also studied, and the results indicate a
competitive type of inhibition for α-amylase activity by xanthones 2c, 3b, 3c and γ-mangostin (6). On the
other hand, non-competitive inhibition mechanisms can be ascribed for all xanthones 1–6 against
α-glucosidase. The present work can open a promising area of research based on the design of novel
xanthone derivatives, based on natural ones, for targeting key enzymes involved in glucose metabolism
and therefore in the management of type 2 diabetes mellitus.The work was supported by UIBD/00690/2020 and UIDB/50006/2020 with funding from FCT/MCTES through national
funds, and by EXPL/MED-QUI/0815/2021, with funding from FCT. Carina Proença acknowledges funding from FCT and
MCTES through national funds and COMPETE, grant number PTDC/MED-QUI/29243/2017 -POCI-01-0145-FEDER-029243.
Marisa Freitas acknowledges her contract under the Scientific Employment Stimulus - Individual Call (CEEC Individual)
2020.04126.CEECIND/CP1596/CT0006.info:eu-repo/semantics/publishedVersio
Water quantity and quality under future climate and societal scenarios: a basin-wide approach applied to the Sorraia river, Portugal
Water resources are impacted by several stressors like over-population and over
consumption that compromises their availability. These stressors are expected to progressively
intensify due to climate change in most regions of the world, with direct impact on watersheds and
river systems. This study investigates the effect of different watershed pressure scenarios due to
climate change in the hydrological regime of the Sorraia River basin, Portugal. This catchment
includes one of the largest irrigated areas in the country, thus being strongly influenced by
anthropogenic activities, associated to hydrological (irrigation, flow regulation, damming) and
nutrient stressors. The SoilWater Assessment Tool has been used to simulate water flow and nutrient
dynamics in the watershed while considering inputs from two climate models and three societal
scenarios. Results have shown that the predicted rainfall reductions will have a significant impact
on river flow and nutrient concentrations when compared to baseline conditions. River flow will
expectably decrease by 75%, while nitrogen and phosphorus concentrations in river water will
expectably increase by 500% and 200%, respectively. These differences are more evident for storylines
that consider increasing pressures such as population growth and agricultural expansion marked
with unsustainable practices and increased reliance on technology. The results of this study indicate a
possible future outcome and provide effective guidelines for the formulation of water management
policies to counter the impacts of climate change and corresponding environmental pressures in the
Sorraia River basininfo:eu-repo/semantics/publishedVersio
Novel chromone and xanthone derivatives: synthesis and ROS/RNS scavenging activities
Chromones and xanthones are oxygen-containing heterocyclic compounds acknowledged by their antioxidant properties. In an effort to develop novel agents with improved activity, a series of compounds belonging to these chemical classes were prepared. Their syntheses involve the condensation of appropriate 2-methyl-4H-chromen-4-ones, obtained via Baker-Venkataraman rearrangement, with (E)-3-(3,4-dimethoxyphenyl)acrylaldehyde to provide the corresponding 2-[(1E,3E)-4-(3,4-dimethoxyphenyl)buta-1,3-dien-1-yl]-4H-chromen-4-ones. Subsequent electrocyclization and oxidation of these compounds led to the synthesis of 1-aryl-9H-xanthen-9-ones. After cleavage of the protecting groups, hydroxylated chromones and xanthones were assessed as scavenging agents against both reactive oxygen species (ROS) [superoxide radical (O2(•-)), hydrogen peroxide (H2O2), hypochlorous acid (HOCl), singlet oxygen ((1)O2), and peroxyl radical (ROO(•))] and reactive nitrogen species (RNS) [nitric oxide ((•)NO) and peroxynitrite anion (ONOO(-))]. Generally, all the tested new hydroxylated chromones and xanthones exhibited scavenger effects dependent on the concentration, with IC50 values found in the micromolar range. Some of them were shown to have improved scavenging activity when compared with previously reported analogues, allowing the inference of preliminary conclusions on the structure-activity relationship
Design, synthesis and preliminar antioxidant evaluation of new hydroxy- chromone and xanthone derivatives
Chromone and xanthone derivativas are well-known for their outstanding antioxidant
properties. ln an effort to develop new antioxidants with improved efficacy, here we
cteveloped a new synthetic strategy to prepare hydroxylated chromones 3 and xanthones 4
with extended conjugated rr-systems. The synthetic strategy involved the aldolcondensation
of 2-methylchromones 1 with cinnamaldehyde 2 to give chromones 3.
Subsequent electrocyclization and oxidation of chromones 3 afforded xanthones 4 (Fig. 1 ).
The scavenging activities of both derivativas 3 and 4 were addressed against both reactive
oxygen species (ROS) and reactive nitrogen species (RNS). Ali tested compounds exhibited
scavenger effects dependent on the concentration, with ICso values found in the micromolar
range [1].Sincere thanks are expressed to Faculdade de Farmácia da Universidade do Porto, Universidade de Aveiro, Instituto
Politécnico de Bragança, Fundação para a Ciência e a Tecnologia (FCT, Portugal), European Union, QREN, FEDER
and COMPETE funding UCIBIOREQUIMTE (FCT UID/Multi/04378/2013) and OOPNA (FCT UID/QUI/00062/2013)
Research Units and also to the Portuguesa National NMR Network (RNRMN).info:eu-repo/semantics/publishedVersio
Evaluation of the trophic status in a Mediterranean reservoir under climate change: an integrated modelling approach
This study describes an integrated modelling approach to better understand the trophic status of the
Montargil reservoir (southern Portugal) under climate change scenarios. The SWAT and CE-QUAL-W2
models were applied to the basin and reservoir, respectively, for simulating water and nutrient
dynamics while considering one climatic scenario and two decadal timelines (2025–2034 and
2055–2064). Model simulations showed that the dissolved oxygen concentration in the reservoir’s
hypolimnion is expected to decrease by 60% in both decadal timelines, while the chlorophyll-a
concentration in the reservoir’s epiliminion is expected to increase by 25%. The total phosphorus
concentration (TP) is predicted to increase in the water column surface by 63% and in the hypolimion
by 90% during the 2030 timeline. These results are even more severe during the 2060 timeline. Under
this climate change scenario, the reservoir showed a eutrophic state during 70–80% of both
timelines. Even considering measures that involve decreases in 30 to 35% of water use, the eutrophic
state is not expected to improveinfo:eu-repo/semantics/publishedVersio
The antioxidant activity of novel chromones and xanthones: a structure-activity relationship
Chromones and xanthones are oxygen-containing heterocyclic compounds with bioactive
properties widely reported in the literature, specially concerning to their antioxidant
properties. The search for new natural and synthetic chromone and xanthone derivatives order
to evaluate and discover new structural features rendering optimized biological effects has
been a challenge. Thus, the aim of this work was to evaluate the scavenging activity of
reactive oxygen (ROS) and nitrogen (RNS) species of new synthetic hydroxylated chromones
and xanthones (Fig. 1) using in vitro non-cellular systems. These compounds exhibited
scavenger effects dependent on the concentration, with IC50 values found at the micromolar
range. The overall scavenging activity of chromones was better than xanthones, specially the
one of chromone 3A. In conclusion, the novel tested chromone and xanthone scaffolds proved
to be promising pharmacophores with potential therapeutic applications as antioxidant agents