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1.
Dalton Trans ; 53(20): 8791-8802, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38713065

RESUMO

Two new spin crossover (SCO) Fe(III) compounds were prepared, their structures were analysed and their magnetic properties were investigated. An exhaustive analysis of the effects of halogen substitution and aromatic ring functionalisation on the magnetic properties of non-solvated Fe(III) perchlorate complexes has been performed. Through comparative analysis, different magnetic profiles were found for the compounds studied, namely F (1), Cl (2), H (3), Br (4a, 4b), and I (5). Using tools like Hirshfeld analysis, the study revealed patterns in octahedral distortions and deviations from the ideal octahedral geometry. The SCO phenomenon as the conducting wire in this study, emphasises the influence of intermolecular interactions on the low spin (LS) to high spin (HS) transitions in these halogen-substituted complexes. The prevalence of H⋯H contributions has been demonstrated, albeit being the weakest and an inverse strength relationship in H⋯X interactions ranging from F to I. The findings not only interpret the intricate balance between halogen substitution, functionalisation, and intermolecular interactions in modulating magnetic properties but also direct future works in designing similar molecular systems.

2.
Neurobiol Stress ; 30: 100619, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38500791

RESUMO

Sorting Nexin 27 (SNX27) is a brain-enriched endosome-associated cargo adaptor that shapes excitatory control, being relevant for cognitive and reward processing, and for several neurological conditions. Despite this, SNX27's role in the nervous system remains poorly explored. To further understand SNX27 function, we performed an extensive behavioral characterization comprising motor, cognitive and emotional dimensions of SNX27+/- mice. Furthermore, attending on the recently described association between SNX27 function and cellular stress signaling mechanisms in vitro, we explored SNX27-stress interplay using a Caenorhabditis elegans Δsnx-27 mutant and wild-type (WT) rodents after stress exposure. SNX27+/- mice, as C. elegans Δsnx-27 mutants, present cognitive impairments, highlighting a conserved role for SNX27 in cognitive modulation across species. Interestingly, SNX27 downmodulation leads to anxiety-like behavior in mice evaluated in the Elevated Plus Maze (EPM). This anxious phenotype is associated with increased dendritic complexity of the bed nucleus of the stria terminalis (BNST) neurons, and increased complexity of the basolateral amygdala (BLA) pyramidal neurons. These findings highlight the still unknown role of SNX27 in anxiety regulation. Moreover, we uncovered a direct link between SNX27 dysfunction and stress susceptibility in C. elegans and found that stress-exposed rodents display decreased SNX27 levels in stress-susceptible brain regions. Altogether, we provided new insights on SNX27's relevance in anxiety-related behaviors and neuronal structure in stress-associated brain regions.

3.
Adv Healthc Mater ; : e2303861, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38041539

RESUMO

Responsive magnetic nanomaterials offer significant advantages for innovative therapies, for instance, in cancer treatments that exploit on-demand delivery on alternating magnetic field (AMF) stimulus. In this work, biocompatible magnetic bionanocomposite films are fabricated from chitosan by film casting with incorporation of magnetite nanoparticles (MNPs) produced by facile one pot synthesis. The influence of synthesis conditions and MNP concentration on the films' heating efficiency and heat dissipation are evaluated through spatio-temporal mapping of the surface temperature changes by video-thermography. The cast films have a thickness below 100 µm, and upon exposure to AMF (663 kHz, 12.8 kA m-1 ), induce exceptionally strong heating, reaching a maximum temperature increase of 82 °C within 270 s irradiation. Further, it is demonstrated that the films can serve as substrates that supply heat for multiple hyperthermia scenarios, including: i) non-contact automated heating of cell culture medium, ii) heating of gelatine-based hydrogels of different shapes, and iii) killing of cancerous melanoma cells. The films are versatile components for non-contact stimulus with translational potential in multiple biomedical applications.

4.
Front Chem ; 11: 1106349, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37025548

RESUMO

We report the synthesis and characterization of a group of benzoylhydrazones (Ln) derived from 2-carbaldehyde-8-hydroxyquinoline and benzylhydrazides containing distinct para substituents (R = H, Cl, F, CH3, OCH3, OH and NH2, for L1-7, respectively; in L8 isonicotinohydrazide was used instead of benzylhydrazide). Cu(II) complexes were prepared by reaction of each benzoylhydrazone with Cu(II) acetate. All compounds were characterized by elemental analysis and mass spectrometry as well as by FTIR, UV-visible absorption, NMR or electron paramagnetic resonance spectroscopies. Complexes isolated in the solid state (1-8) are either formulated as [Cu(HL)acetate] (with L1 and L4) or as [Cu(Ln)]3 (n = 2, 3, 5, 6, 7 and 8). Single crystal X-ray diffraction studies were done for L5 and [Cu(L5)]3, confirming the trinuclear formulation of several complexes. Proton dissociation constants, lipophilicity and solubility were determined for all free ligands by UV-Vis spectrophotometry in 30% (v/v) DMSO/H2O. Formation constants were determined for [Cu(LH)], [Cu(L)] and [Cu(LH-1)] for L = L1, L5 and L6, and also [Cu(LH-2)] for L = L6, and binding modes are proposed, [Cu(L)] predominating at physiological pH. The redox properties of complexes formed with L1, L5 and L6 are investigated by cyclic voltammetry; the formal redox potentials fall in the range of +377 to +395 mV vs. NHE. The binding of the Cu(II)-complexes to bovine serum albumin was evaluated by fluorescence spectroscopy, showing moderate-to-strong interaction and suggesting formation of a ground state complex. The interaction of L1, L3, L5 and L7, and of the corresponding complexes with calf thymus DNA was evaluated by thermal denaturation. The antiproliferative activity of all compounds was evaluated in malignant melanoma (A-375) and lung (A-549) cancer cells. The complexes show higher activity than the corresponding free ligand, and most complexes are more active than cisplatin. Compounds 1, 3, 5, and 8 were selected for additional studies: while these complexes induce reactive oxygen species and double-strand breaks in both cancer cells, their ability to induce cell-death by apoptosis varies. Within the set of compounds tested, 8 emerges as the most promising one, presenting low IC50 values, and high induction of oxidative stress and DNA damage, which eventually lead to high rates of apoptosis.

5.
J Prim Care Community Health ; 14: 21501319231159973, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36932868

RESUMO

BACKGROUND: Sexually transmitted infections (STIs) are a public health problem with a high risk of morbidity and community transmissibility. Evidence points to their continuous increase. This study describes the design, development, and implementation of a community-based STI prevention program for community healthcare users. METHODS: Based on the Health Planning Process design method, a structured, community-based intervention program on STI counseling and detection was conducted in a primary health care unit in Lisbon. Two data collection instruments were applied in the diagnosis of the situation, namely the Health Literacy Survey Portugal (ILS-PT) and the STD Attitude Scale, to 47 patients who attended the health consultation on STI counseling and detection in a primary care unit in Lisbon. Two interventions were implemented, the health education session and the provision of an educational poster. In the evaluation of the project, the acceptance and satisfaction of the patients with the implemented interventions were considered as outcome indicators. A descriptive statistical analysis of the data was performed. RESULTS: The participants shows considerably low levels of health literacy and high-risk behaviors for acquiring STIs. After an intervention, a high percentage of the participants point out the project as exciting and valuable and reveal having acquired knowledge that allowed them to improve their health. Furthermore, the patients were very satisfied with the implemented health education session and the educational poster. CONCLUSION: This project revealed the urgent and important need to implement community intervention projects to prevent STIs and promote health literacy among the most vulnerable groups.


Assuntos
Infecções por HIV , Letramento em Saúde , Infecções Sexualmente Transmissíveis , Humanos , Promoção da Saúde , Infecções Sexualmente Transmissíveis/prevenção & controle , Aconselhamento , Educação em Saúde , Infecções por HIV/prevenção & controle
7.
Nanomaterials (Basel) ; 12(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35683726

RESUMO

Magnetite nanoparticles were synthesized by the co-precipitation method with and without the assistance of an additive, namely, gelatin, agar-agar or pectin, using eco-friendly conditions and materials embodying a green synthesis process. X-ray diffraction and transmission electron microscopy were used to analyze the structure and morphology of the nanoparticles. Magnetic properties were investigated by SQUID magnetometry and 57Fe Mössbauer spectroscopy. The results show that the presence of the additives implies a higher reproducibility of the morphological magnetic nanoparticle characteristics compared with synthesis without any additive, with small differences associated with different additives. To assess their potential for magnetic hyperthermia, water-based suspensions of these nanoparticles were prepared with and without citric acid. The stable solutions obtained were studied for their structural, magnetic and heating efficiency properties. The results indicate that the best additive for the stabilization of a water-based emulsion and better heating efficiency is pectin or a combination of pectin and agar-agar, attaining an intrinsic loss power of 3.6 nWg-1.

9.
Methods Mol Biol ; 2494: 47-59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35467200

RESUMO

Shoot branching is an important trait that depends on the activity of axillary meristems and buds and their outgrowth into branches. It is remarkably plastic, being influenced by a number of external cues, such as light, temperature, soil nutrients, and mechanical manipulation. These are transduced into an internal hormone signaling network where auxin, cytokinins, and strigolactones play leading regulatory roles. Recently, sugars have also emerged as important signals promoting bud activation. These signals are in part integrated by the bud-specific growth repressor BRANCHED1 (BRC1).To understand how shoot branching is affected by particular growth conditions or in specific plant lines, it is necessary to count the number of branches and/or quantify other branch-related parameters. Here we describe how to perform such quantifications in Arabidopsis and in tomato.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Solanum lycopersicum , Arabidopsis/genética , Ácidos Indolacéticos , Mutação , Brotos de Planta , Fatores de Transcrição/genética
11.
J Sex Marital Ther ; 48(5): 489-501, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34839803

RESUMO

This study researched how age predicts women's cognitive and emotional appraisal of sex pictures. One hundred and fifty five women were exposed to romantic, sexually moderate and sexually explicit pictures. Women reported on the emotional valence, subjective sexual arousal, and level of sexual content attributed to the pictures; women's sexual beliefs were further evaluated. Findings revealed that age predicted increased pleasantness to sexually moderate and explicit pictures, as well as higher subjective sexual arousal to all type of pictures. Some predictions were moderated by sexual beliefs and exposure time, pointing the role of contextual factors in women's appraisal of erotica.


Assuntos
Literatura Erótica , Comportamento Sexual , Cognição , Emoções , Literatura Erótica/psicologia , Feminino , Humanos , Excitação Sexual , Comportamento Sexual/psicologia
12.
Toxics ; 9(12)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34941763

RESUMO

In this work, carbon dots (CD) were synthesized and coupled to titanium dioxide (TiO2) to improve the photodegradation of antibiotics in aquaculture effluents under solar irradiation. Oxolinic acid (OXA) and sulfadiazine (SDZ), which are widely used in aquaculture, were used as target antibiotics. To prepare nanocomposites of CD containing TiO2, two modes were used: in-situ (CD@TiO2) and ex-situ (CD/TiO2). For CD synthesis, citric acid and glycerol were used, while for TiO2 synthesis, titanium butoxide was the precursor. In ultrapure water (UW), CD@TiO2 and CD/TiO2 showed the largest photocatalytic effect for SDZ and OXA, respectively. Compared with their absence, the presence of CD@TiO2 increased the photodegradation of SDZ from 23 to 97% (after 4 h irradiation), whereas CD/TiO2 increased the OXA photodegradation from 22 to 59% (after 1 h irradiation). Meanwhile, in synthetic sea salts (SSS, 30‱, simulating marine aquaculture effluents), CD@TiO2 allowed for the reduction of SDZ's half-life time (t1/2) from 14.5 ± 0.7 h (in absence of photocatalyst) to 0.38 ± 0.04 h. Concerning OXA in SSS, the t1/2 remained the same either in the absence of a photocatalyst or in the presence of CD/TiO2 (3.5 ± 0.3 h and 3.9 ± 0.4 h, respectively). Overall, this study provided novel perspectives on the use of eco-friendly CD-TiO2 nanocomposites for the removal of antibiotics from aquaculture effluents using solar radiation.

13.
Nanomaterials (Basel) ; 11(11)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34835704

RESUMO

Magnetic nanoparticles (NP), such as magnetite, have been the subject of research for application in the biomedical field, especially in Magnetic Hyperthermia Therapy (MHT), a promising technique for cancer therapy. NP are often coated with different compounds such as natural or synthetic polymers to protect them from oxidation and enhance their colloidal electrostatic stability while maintaining their thermal efficiency. In this work, the synthesis and characterization of magnetite nanoparticles coated with fucoidan, a biopolymer with recognized biocompatibility and antitumoral activity, is reported. The potential application of NP in MHT was evaluated through the assessment of Specific Loss Power (SLP) under an electromagnetic field amplitude of 14.7 kA m-1 and at 276 kHz. For fucoidan-coated NP, it was obtained SLP values of 100 and 156 W/g, corresponding to an Intrinsic Loss Power (ILP) of 1.7 and 2.6 nHm2kg-1, respectively. These values are, in general, higher than the ones reported in the literature for non-coated magnetite NP or coated with other polymers. Furthermore, in vitro assays showed that fucoidan and fucoidan-coated NP are biocompatible. The particle size (between ca. 6 to 12 nm), heating efficiency, and biocompatibility of fucoidan-coated magnetite NP meet the required criteria for MHT application.

15.
Z Anorg Allg Chem ; 647(14): 1429-1435, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34413550

RESUMO

In the present work we have prepared and fully characterized several Fe(0) complexes of the type [Fe(PNP)(CO)2] treating Fe(II) complexes [Fe(PNP)(Cl)2] with KC8 in the presence of carbon monoxide. While complexes [Fe(PNPNMe-iPr)(CO)2], [Fe(PNPNEt-iPr)(CO)2] adopt a trigonal bipyramidal geometry, the bulkier and more electron rich [Fe(PNPNH-tBu)(CO)2] is closer to a square pyramidal geometry. Mössbauer spectra showed isomer shifts very close to 0 and similar to those reported for Fe(I) systems. Quadrupole splitting values range between 2.2 and 2.7 mm s-1 both in experiments and DFT calculations, while those of Fe(I) complexes are much smaller (∼0.6 mm s-1).

16.
Cancers (Basel) ; 13(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809543

RESUMO

Biglycan (BGN gene), an extracellular proteoglycan, has been described to be associated with cancer aggressiveness. The purpose of this study was to clarify the clinical value of biglycan as a biomarker in multiple independent GC cohorts and determine the in vitro and in vivo role of biglycan in GC malignant features. We found that BGN is commonly over-expressed in all analyzed cohorts, being associated with disease relapse and poor prognosis in patients with advanced stages of disease. In vitro and in vivo experiments demonstrated that biglycan knock-out GC cells display major phenotypic changes with a lower cell survival, migration, and angiogenic potential when compared with biglycan expressing cells. Biglycan KO GC cells present increased levels of PARP1 and caspase-3 cleavage and a decreased expression of mesenchymal markers. Importantly, biglycan deficient GC cells that were supplemented with exogenous biglycan were able to restore biological features, such as survival, clonogenic and migratory capacities. Our in vitro and in vivo findings were validated in human GC samples, where BGN expression was associated with several oncogenic gene signatures that were associated with apoptosis, cell migration, invasion, and angiogenesis. This study provided new insights on biglycan role in GC that should be taken in consideration as a key cellular regulator with major impact in tumor progression and patients' clinical outcome.

17.
eNeuro ; 8(3)2021.
Artigo em Inglês | MEDLINE | ID: mdl-33879568

RESUMO

Sex hormone levels continuously fluctuate across the reproductive cycle, changing the activity of neuronal circuits to coordinate female behavior and reproductive capacity. The ventrolateral division of the ventromedial hypothalamus (VMHvl) contains neurons expressing receptors for sex hormones and its function is intimately linked to female sexual receptivity. However, recent findings suggest that the VMHvl is functionally heterogeneous. Here, we used whole recordings and intracellular labeling to characterize the electrophysiological and morphologic properties of individual VMHvl neurons in naturally cycling females and report the existence of multiple electrophysiological phenotypes within the VMHvl. We found that the properties of progesterone receptor expressing (PR+) neurons, but not PR- neurons, depended systematically on the neuron's location along the anterior-posterior (AP) axis of the VMHvl and the phase within the reproductive cycle. Prominent among this, the resting membrane potential of anterior PR+ neurons decreased during the receptive phase, while the excitability of medial PR+ neurons increased during the non-receptive phase. During the receptive phase of the cycle, posterior PR+ neurons simultaneously showed an increase in dendritic complexity and a decrease in spine density. These findings reveal an extensive diversity of local rules driving structural and physiological changes in response to fluctuating levels of sex hormones, supporting the anatomic and functional subdivision of the VMHvl and its possible role in the orchestration of different aspects of female socio-sexual behavior.


Assuntos
Hipotálamo , Receptores de Progesterona , Feminino , Humanos , Hipotálamo/metabolismo , Neurônios/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Reprodução
18.
Environ Sci Pollut Res Int ; 28(14): 17228-17243, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33394452

RESUMO

The increased use of pharmaceutical and personal care products (PPCPs) has contributed to the contamination of water systems and put pressure on the development of new techniques to deal with this problem. Acetaminophen (paracetamol), a common analgesic and antipyretic drug, and caffeine, a known central nervous system stimulant, are being used frequently by many people and found in large amounts in wastewater systems. In this work, their removal, by photocatalytic degradation, was promoted using magnetic nanoparticles (NPs) based on iron oxides. Besides being obtained from cheap and plentiful source, the magnetic properties of these NPs provide an easy way to separate them from the solution when the reaction is complete. Three types of hematite-based NPs, one pure (1) and two of them composed by a magnetite core partially (2) or completely (3) covered by a hematite shell, were synthesized and characterized. Sample 2 was the best photocatalyst for both pollutants' photo-assisted degradation. Under UV-vis irradiation and using a 0.13 g catalyst/L solution, the total acetaminophen and caffeine degradation (20 ppm/150 mL) was achieved in 45 min and 60 min, respectively. The identification of some of the intermediate products was carried out by liquid chromatography in combination with electrospray ionization mass spectrometry. A complementary Density Functional Theory (DFT) study revealed the relative stability of several species formed during the acetaminophen and caffeine degradation processes and gave some insight about the most favorable degradation pathways.


Assuntos
Nanopartículas de Magnetita , Poluentes Químicos da Água , Acetaminofen , Cafeína , Catálise , Compostos Férricos , Óxido Ferroso-Férrico , Humanos , Cinética , Titânio , Poluentes Químicos da Água/análise
20.
Acta Med Port ; 34(10): 692-695, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33159729

RESUMO

In obsessive-compulsive disorder, pedophilia-themed obsessions-distressing intrusive thoughts about being sexually attracted to, or sexually abusing, children-are the most distressing for patients and the most misdiagnosed among healthcare professionals. Our aim is to present a case report highlighting the role stigma plays in delaying treatment, the clinical challenges in the diagnosis, and in the treatment of pedophilia-themed obsessive-compulsive disorder, in order to address the lack of literature on the subject. The case concerns a 33-year-old man with suicidal thoughts associated with the unbearable suffering caused by pedophilia-themed obsessions he had been having over the previous decade, without ever asking for help. This situation was highly disabling, leaving him mostly isolated in his bedroom. After the differential diagnosis was made, a treatment plan combining pharmacological and cognitive-behavioural therapy was implemented. After 18 months he showed a degree of remission that made it possible for him to apply for a job.


Na perturbação obsessivo-compulsiva as obsessões pedofílicas - pensamentos intrusivos sobre ser sexualmente excitado, ou abusar sexualmente, de crianças - estão entre os mais angustiantes para os doentes e os mais incorretamente diagnosticados pelos profissionais de saúde. O nosso objetivo é apresentar um caso clínico destacando o papel que o estigma tem no atraso do início do tratamento e os desafios clínicos que se verificam em relação ao diagnóstico e ao tratamento desta perturbação, de modo a colmatar a falta de literatura sobre o assunto. O caso é relativo a um homem de 33 anos, com ideação suicida associada ao sofrimento insuportável causado pelas obsessões sexuais pedofílicas que tinha desde há uma década, sem nunca ter recorrido a um profissional de saúde. Esta situação teve muito impacto no seu funcionamento deixando-o maioritariamente isolado no seu quarto. Após o diagnóstico diferencial, implementou-se o projeto terapêutico combinando tratamento farmacológico e psicoterapia cognitivo-comportamental. Após 18 meses o doente apresentou uma melhoria significativa permitindo-o concorrer a um emprego.


Assuntos
Terapia Cognitivo-Comportamental , Transtorno Obsessivo-Compulsivo , Pedofilia , Adulto , Criança , Cognição , Humanos , Masculino , Transtorno Obsessivo-Compulsivo/terapia , Pedofilia/terapia , Comportamento Sexual
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