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1.
Front Psychol ; 14: 1165322, 2023.
Article in English | MEDLINE | ID: mdl-37275696

ABSTRACT

Introduction: Alcohol-related problems disproportionally affect people experiencing homelessness. As the first wave of the COVID-2019 pandemic spread in 2020, a number of emergency shelters were opened in Lisbon. Increased difficulties in obtaining alcohol could have led to an increased incidence of alcohol withdrawal. Therefore, a low-threshold harm reduction intervention was introduced to these emergency shelters. This consisted of a fixed medication treatment, made available immediately for those with specific conditions, without the need for a medical evaluation or abstinence from alcohol, together with an offer of subsequent access to specialized addiction centers. The Problemas Ligados ao Álcool em Centros de Emergência (PLACE) study (alcohol-related problems in emergency shelters) is a retrospective mixed-methods observational study. It describes the demographic, health, and social characteristics of shelter users participating in the program and aims to evaluate the intervention as well as the experience of the patients, professionals, and decision-makers involved. Results: A total of 69 people using shelters self-reported alcohol-related problems. Among them, 36.2% of the people accepted a pharmacological intervention, and 23.2% selected an addiction appointment. The take-up of the intervention was associated with better housing outcomes. A description of an individual's trajectory after leaving the shelter is provided. Discussion: This study suggests that non-abstinence-focused interventions can be useful and well-tolerated in treating addiction in this population.

2.
J Oral Sci ; 65(2): 81-86, 2023 Mar 30.
Article in English | MEDLINE | ID: mdl-36858605

ABSTRACT

PURPOSE: To evaluate the effect of intra-radicular cleaning protocols after post-space preparation (PSP) on marginal adaptation of a luting agent to root dentin. METHODS: Eighty bovine incisors were sectioned transversely to obtain 18-mm-long root sections. The roots were prepared with ProTaper instruments and filled using Tagger's hybrid technique. PSP was performed at a length of 14 mm using #3-5 Largo drills. The roots were distributed into eight groups according to the chelating solution used (17% EDTA or 0.2% Chitosan) and the chelating activation/delivery method employed (conventional needle irrigation [CNI], EndoActivator [EA], XP-Endo Finisher [XPF] or passive ultrasonic irrigation [PUI]). The fiber posts were cemented using self-adhesive resin cement, and the roots were sectioned to obtain three discs from each root third. The dentin discs were observed under an optical microscope at ×40 magnification to assess marginal adaptation. The different protocols were compared considering the frequency of the marginal adaptation scores using the Kruskal-Wallis test, followed by the Dwass-Steel-Critchlow-Fligner test (α = 5%). RESULTS: The use of 17% EDTA resulted in better marginal adaptation (P < 0.001). PUI yielded results that were similar to those for EA (P = 0.949) and superior to those for XPF (P = 0.020). The combination of 17% EDTA + PUI provided a greater number of interfaces without marginal gaps (P < 0.001). CONCLUSION: The cleaning protocol influenced the marginal adaptation of resin cement to root dentin.


Subject(s)
Dental Cements , Post and Core Technique , Animals , Cattle , Dental Cements/pharmacology , Resin Cements , Edetic Acid/pharmacology , Microscopy, Electron, Scanning , Dentin , Root Canal Preparation/methods , Dental Pulp Cavity , Root Canal Irrigants/pharmacology
3.
Biol Open ; 12(1)2023 01 01.
Article in English | MEDLINE | ID: mdl-36504260

ABSTRACT

In recent decades, study of the actions of bioactive lipids such as lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) has increased since they are involved in regulating many processes, including self-renewal of embryonic stem cells, embryo development and cancer. Phospholipid phosphatase type 3 (PLPP3) has been shown to be a key player in regulating the balance of these lipids and, in consequence, their signaling. Different lines of evidence suggest that PLPP3 could play a role in endoderm development. To approach this hypothesis, we used mouse embryonic stem cells (ESC) as a model to study Plpp3 function in self-renewal and the transition towards differentiation. We found that lack of PLPP3 mainly affects endoderm formation during differentiation of suspension-formed embryoid bodies. PLPP3-deficient ESC strongly decrease the amount of FOXA2-expressing cells and fail to properly downregulate the expression of pluripotency factors when subjected to an endoderm-directed differentiation protocol. Impaired endoderm differentiation correlated with a transient reduction in nuclear localization of YAP1. These phenotypes were rescued by transiently restoring the expression of catalytically active hPLPP3. In conclusion, PLPP3 plays a role in downregulating pluripotency-associated factors and in endodermal differentiation. PLPP3 regulates proper lipid/YAP1 signaling required for endodermal differentiation.


Subject(s)
Embryonic Stem Cells , Mouse Embryonic Stem Cells , Animals , Mice , Cell Differentiation/genetics , Embryonic Stem Cells/metabolism , Phosphoric Monoester Hydrolases/metabolism , Lipids
4.
Biomolecules ; 12(4)2022 04 07.
Article in English | MEDLINE | ID: mdl-35454139

ABSTRACT

Cytochromes-c are ubiquitous heme proteins with enormous impact at the cellular level, being key players in metabolic processes such as electron transfer chains and apoptosis. The assembly of these proteins requires maturation systems that catalyse the formation of the covalent thioether bond between two cysteine residues and the vinyl groups of the heme. System III is the maturation system present in Eukaryotes, designated CcHL or HCCS. This System requires a specific amino acid sequence in the apocytochrome to be recognized as a substrate and for heme insertion. To explore the recognition mechanisms of CcHL, the bacterial tetraheme cytochrome STC from Shewanella oneidensis MR-1, which is not a native substrate for System III, was mutated to be identified as a substrate. The results obtained show that it is possible to convert a bacterial cytochrome as a substrate by CcHL, but the presence of the recognition sequence is not the only factor that induces the maturation of a holocytochrome by System III. The location of this sequence in the polypeptide also plays a role in the maturation of the c-type cytochrome. Furthermore, CcHL appears to be able to catalyse the binding of only one heme per polypeptide chain, being unable to assemble multiheme cytochromes c, in contrast with bacterial maturation systems.


Subject(s)
Cytochromes c , Lyases , Cytochromes c/metabolism , Eukaryota/metabolism , Eukaryotic Cells/metabolism , Heme/metabolism , Lyases/metabolism
5.
Front Microbiol ; 11: 815, 2020.
Article in English | MEDLINE | ID: mdl-32457717

ABSTRACT

Microbial electrochemical technologies (METs) have emerged in recent years as a promising alternative green source of energy, with microbes consuming organic matter to produce energy or valuable byproducts. It is the ability of performing extracellular electron transfer that allows these microbes to exchange electrons with an electrode in these systems. The low levels of current achieved have been the limiting factor for the large-scale application of METs. Shewanella oneidensis MR-1 is one of the most studied electroactive organisms regarding extracellular electron transfer, and it has been shown that biofilm formation is a key factor for current generation. The transcription factor bolA has been identified as a central player in biofilm formation in other organisms, with its overexpression leading to increased biofilm. In this work we explore the effect of this gene in biofilm formation and current production by S. oneidensis MR-1. Our results demonstrate that an increased biofilm formation and consequent current generation was achieved by the overexpression of this gene. This information is crucial to optimize electroactive organisms toward their practical application in METs.

6.
Adv Microb Physiol ; 75: 69-135, 2019.
Article in English | MEDLINE | ID: mdl-31655743

ABSTRACT

Multihaem cytochromes c are widespread in nature where they perform numerous roles in diverse anaerobic metabolic pathways. This is achieved in two ways: multihaem cytochromes c display a remarkable diversity of ways to organize multiple hemes within the protein frame; and the hemes possess an intrinsic reactive versatility derived from diverse spin, redox and coordination states. Here we provide a brief survey of multihaem cytochromes c that have been characterized in the context of their metabolic role. The contribution of multihaem cytochromes c to dissimilatory pathways handling metallic minerals, nitrogen compounds, sulfur compounds, organic compounds and phototrophism are described. This aims to set the stage for the further exploration of the vast unknown "cytochromome" that can be anticipated from genomic databases.


Subject(s)
Cytochromes c/metabolism , Heme/metabolism , Oxidation-Reduction
7.
Anim Nutr ; 5(2): 163-173, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31193932

ABSTRACT

An experiment was designed to determine the influence of fibre and betaine on the development of the intestine, liver and pancreas of broilers from hatch to 14 d of age. A total of 250-day-old Cobb 500 male broilers were allocated to 16 cages with 15 broilers each. Treatments were arranged in a 2 × 4 factorial design, consisting of 2 feed formulations (low and high fibre diets) and 4 levels of betaine (0, 1, 3 or 5 kg/t). At hatch, 10 birds in total were euthanised, and samples of the liver, pancreas, yolk sac and intestine were collected for reference of the analysed parameters before the start of the trial. On d 4, 9 and 14, 5 birds per cage (10 birds per treatment) were selected, euthanised and treated as the same as the birds at hatch. Villus height and width and crypt depth were determined on the duodenum samples, and absorptive area was calculated. The number of enterocytes in mitosis at the villus was determined by a positive reaction to antibody for Ki67 protein, and fused villus was evaluated visually. The relative weight of the yolk sac reduced (P < 0.05) as birds aged while the intestine and liver reached a maximum (P < 0.05) at around d 4 and the pancreas at d 9. Birds fed the high fibre diet had greater feed intake, lower relative weight of the pancreas and higher villus (P < 0.05) than birds fed the low fibre diet. Villus width increased (P < 0.05) at 4 d of age, and this was associated with fused villus. Betaine inclusion reduced (P < 0.05) villus width, increased (P < 0.05) villus size and absorptive area, and reduced (P < 0.05) the number of enterocytes with positive reaction for the antibody Ki-67. Betaine inclusion reduced the width and increased the absorptive area and the villus height of the duodenum of birds up to 14 d of age. The higher fibre diet increased feed intake and villus height, yet reduced pancreas relative weight, while not affecting body weight gain. This response was possibly due to a dilution effect of the fibre, reducing nutrient absorption and consequently stimulating villus growth to improve absorption rates.

8.
Phys Chem Chem Phys ; 21(5): 2719-2726, 2019 Jan 30.
Article in English | MEDLINE | ID: mdl-30663744

ABSTRACT

Optically detectable labels and probes are commonly used in bioapplications. Together with the miniaturization of analytical platforms based on microfluidic technology, with tuneable properties, they yield unparalleled opportunities towards faster, cheaper and more efficient biomolecule analysis. This work describes the preparation and testing of uniformly shaded polydimethylsiloxane (PDMS) membranes and microfluidic devices used to enhance or inhibit optical detection of fluorescent labels. The uniformly pigmented black-PDMS nanocomposite mixtures have been prepared by adding a known quantity of black pigment to PDMS, and its optical, spectroscopic and morphological properties have been characterized. The effect of pigment-to-DMS mixing ratio has been investigated by Ultra-Violet/Visible, near infrared and middle infrared spectroscopies; scanning electron microscopy and atomic force microscopy; and contact angle measurements. The results demonstrate that optical and spectroscopic properties of black-PDMS are strongly altered with the progressive inclusion of black pigment while wetting behaviour and morphology are maintained. Surface contact angle decreases more prominently with the decreasing ratio of DMS-to-curing agent than for the inclusion of pigment nanocomposite in the mixture. The ability to tune optical properties of PDMS has been experimentally demonstrated in a Black-PDMS nanocomposite microfluidic chip cast and bonded to glass. The results show double the signal-to-noise in fluorescence images as compared to pure PDMS devices, demonstrating a very promising integrated optical detection strategy for portable microfluidic systems.

9.
Front Plant Sci ; 8: 1931, 2017.
Article in English | MEDLINE | ID: mdl-29184560

ABSTRACT

The Vitex genus (Lamiaceae) produces a plethora of metabolites that include ecdysteroids and terpenoids, some of which have demonstrated insect repellent properties. The volatile composition of several members of this genus has not been chemically defined, as many taxa are endemic to remote ecosystems. In this study, leaves were collected from the northeast of Brazil from Vitex capitata, V. megapotamica, V. gardneriana, and V. rufescens plants and examined for their chemical profile via GC-MS/FID of essential oil extracts. The analyses showed a diversity of terpenoids. Of particular note were seven-member ring sesquiterpenes which were present in great abundance; a dendrogram showed clades separating by the production of bicyclogermacrene, aromadendrane and 5,10-cycloaromadendrane sesquiterpenoids for the four species. Comparison of volatile metabolite profiles to 13 other Vitex species showed strong similarities in the production of some monoterpenes, but varied by their production of larger terpenes, especially those with gem-dimethylcyclopropyl subunits on seven-member ring compounds. From this work, we suggest that the sesquiterpene skeleton with seven member rings is a good chemosystematic biomarker candidate for the Vitex genus. Separation using this biomarker was then validated using Inter-Simple Sequence Repeat profiling. Lastly, experiments examining the toxicity of these four oils against the coconut mite Aceria guerreronis showed that only the oil of V. gardneriana had strong acaricidal activity, with an LC50 of 0.85 mg/mL, thus demonstrating its potential for use as a natural pesticide.

10.
Nanotechnology ; 27(4): 045501, 2016 Jan 29.
Article in English | MEDLINE | ID: mdl-26658286

ABSTRACT

The ability to detect the magnetic fields that surround us has promoted vast technological advances in sensing techniques. Among those, magnetoresistive sensors display an unpaired spatial resolution. Here, we successfully control the linear range of nanometric sensors using an interfacial exchange bias sensing layer coupling. An effective matching of material properties and sensor geometry improves the nanosensor performance, with top sensitivities of 3.7% mT(-1). The experimental results are well supported by 3D micromagnetic and magneto-transport simulations.

11.
Pesqui. vet. bras ; 32(1): 27-36, Jan. 2012. ilus, tab
Article in Portuguese | LILACS | ID: lil-614727

ABSTRACT

Dois experimentos foram desenvolvidos para avaliar a eficiência de ácidos orgânicos frente a Salmonella enterica enterica sorovar Enteritidis (SE) e Minnesota (SM) em frangos. No primeiro experimento foram avaliados 3 tratamentos: T1 - ração adicionada de ácido orgânico, T2 - ração adicionada de ácido orgânico e ácido orgânico na água de bebida, T3 - grupo controle. Todos os animais foram inoculados com SE, via oral. A utilização de ácidos orgânicos na ração (T1) e na ração e na água (T2) diminuíram a excreção de Salmonella no papo e no ceco 7 dias pós inoculação com SE e houve redução de células CD3+ no jejuno dos frangos. No segundo experimento foram avaliados 4 tratamentos sendo T1 - controle, T2 - controle inoculado via oral com Salmonella Minnesota (SM), T3 - animais inoculados via oral com SM e ácidos orgânicos na ração e T4 - animais inoculados via oral com SM e ácidos orgânicos na ração e na água de bebida. Ácidos orgânicos a ração (T3) e na ração e na água (T4) reduziram a excreção de SM em papo de frangos de corte desafiados, 7 dias após inoculação. O uso de ácidos orgânicos na ração e na ração e na água foram mais eficientes em reduzir SE do que SM.


Two experiments were carried out to evaluate effectiveness of organic acids against Salmonella enterica enterica serovars Enteritidis (SE) and Minnesota (SM) in broilers. In the first experiment three treatments were evaluated: T1 - feeding with organic acids, T2 - feeding with organic acids and organic acids in drink water, and T3 - control group. All animals were oral challenged with SE. Organic acids in diet (T1) and organic acids in diet and drink water (T2) reduced the shadding of Salmonella in crop and cecum 7 days post challenged with SE and reduced the CD3+ cells in jejunal mucosa of broilers. In the second experiment four treatments were evaluated, T1 - control group, T2 - control group oral challenged with Salmonella Minnesota (SM); T3 - oral challenged animals with SM and treated with organic acids in diet; T4 - oral challenged animals with SM and treated with organic acids in diet and in drink water. Organic acids in diet (T3) and organic acids in diet and in drink water (T4) reduced the shadding of SM in crop of challenged broilers, 7 days post inoculation The use of organic acids in diet and in water was more effective to control SE than SM.


Subject(s)
Animals , Chickens/anatomy & histology , Chickens/immunology , Chickens/microbiology , Salmonella Infections/chemically induced , Organic Acids , Autopsy/veterinary , Flow Cytometry/veterinary , Intestines/anatomy & histology , Intestines/pathology , Salmonella/isolation & purification
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