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1.
Sensors (Basel) ; 24(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38676025

RESUMO

Wireless communication systems have grown rapidly, moving towards being highly compact, intelligent, and flexible to adapt to changing operating requirements. Multifunctional and highly versatile antennas are key in this development to ensure system quality. Reconfigurable antennas, particularly regarding polarization, allow frequency reuse and enable the mitigation of fading effects. This work presents a square microstrip patch antenna operating in the ISM 5.8 GHz band with reconfigurable polarization by controlling its feeding. This antenna has four different states through the application of a symmetrical DC voltage that controls an RF circuit with PIN diodes. As a result, the microstrip patch can operate with three different polarizations: linear polarization and both circular polarizations (right-handed and left-handed). The antenna was fabricated to validate the proposed concept. The good agreement between the measurement and the simulation results was possible to observe regarding its polarization behaviour, impedance adaptation and radiation pattern.

2.
Cytotherapy ; 26(7): 700-713, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38483360

RESUMO

BACKGROUND AIMS: Parkinson's disease (PD) is the second most common neurodegenerative disorder. The etiology of the disease remains largely unknown, but evidence have suggested that the overexpression and aggregation of alpha-synuclein (α-syn) play key roles in the pathogenesis and progression of PD. Mesenchymal stromal cells (MSCs) have been earning attention in this field, mainly due to their paracrine capacity. The bioactive molecules secreted by MSCs, i.e. their secretome, have been associated with enhanced neuronal survival as well as a strong modulatory capacity of the microenvironments where the disease develops. The selection of the appropriate animal model is crucial in studies of efficacy assessment. Given the involvement of α-syn in the pathogenesis of PD, the evidence generated from the use of animal models that develop a pathologic phenotype due to the action of this protein is extremely valuable. Therefore, in this work, we established an animal model based on the viral vector-mediated overexpression of A53T α-syn and studied the impact of the secretome of bone marrow mesenchymal stromal cells MSC(M) as a therapeutic strategy. METHODS: Adult male rats were subjected to α-syn over expression in the nigrostriatal pathway to model dopaminergic neurodegeneration. The impact of locally administered secretome treatment from MSC(M) was studied. Motor impairments were assessed throughout the study coupled with whole-region (striatum and substantia nigra) confocal microscopy evaluation of histopathological changes associated with dopaminergic neurodegeneration and glial cell reactivity. RESULTS: Ten weeks after lesion induction, the animals received secretome injections in the substantia nigra pars compacta (SNpc) and striatum (STR). The secretome used was produced from bone marrow mesenchymal stromal cells MSC(M) expanded in a spinner flask (SP) system. Nine weeks later, animals that received the viral vector containing the gene for A53T α-syn and treated with vehicle (Neurobasal-A medium) presented dopaminergic cell loss in the SNpc and denervation in the STR. The treatment with secretome significantly reduced the levels of α-syn in the SNpc and protected the dopaminergic neurons (DAn) within the SNpc and STR. CONCLUSIONS: Our results are aligned with previous studies in both α-syn Caenorhabditis elegans models, as well as 6-OHDA rodent model, revealing that secretome exerted a neuroprotective effect. Moreover, these effects were associated with a modulation of microglial reactivity supporting an immunomodulatory role for the factors contained within the secretome. This further supports the development of new studies exploring the effects and the mechanism of action of secretome from MSC(M) against α-syn-induced neurotoxicity.


Assuntos
Modelos Animais de Doenças , Células-Tronco Mesenquimais , Microglia , Neuroproteção , Doença de Parkinson , alfa-Sinucleína , Animais , Células-Tronco Mesenquimais/metabolismo , alfa-Sinucleína/metabolismo , alfa-Sinucleína/genética , Ratos , Masculino , Microglia/metabolismo , Doença de Parkinson/terapia , Doença de Parkinson/metabolismo , Secretoma/metabolismo , Neurônios Dopaminérgicos/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células Cultivadas , Humanos
3.
Int J Mol Sci ; 24(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37958924

RESUMO

Lignin has emerged as a promising eco-friendly multifunctional ingredient for cosmetic applications, due to its ability to protect against ultraviolet radiation and its antioxidant and antimicrobial properties. However, its typical dark color and low water solubility limit its application in cosmetics. This study presents a simple process for obtaining light-colored lignin (LCLig) from sugarcane bagasse (SCB) alkaline black liquor, involving an oxidation treatment with hydrogen peroxide, followed by precipitation with sulfuric acid. The physico-chemical characterization, antioxidant and emulsifying potential of LCLig, and determination of its safety and stability in an oil-in-water emulsion were performed. A high-purity lignin (81.6%) with improved water solubility was obtained, as a result of the balance between the total aromatic phenolic units and the carboxylic acids. In addition, the antioxidant and emulsifying capacities of the obtained LCLig were demonstrated. The color reduction treatment did not compromise the safety of lignin for topical cosmetic applications. The emulsion was stable in terms of organoleptic properties (color, pH, and viscosity) and antioxidant activity over 3 months at 4, 25, and 40 °C.


Assuntos
Cosméticos , Saccharum , Lignina/química , Celulose/química , Saccharum/química , Antioxidantes/farmacologia , Emulsões , Raios Ultravioleta , Beleza , Água
4.
Int J Biol Macromol ; 239: 124262, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37003388

RESUMO

Diet is a crucial factor on health and well-being of livestock animals. Nutritional strengthening with diet formulations is essential to the livestock industry and animal perfor-mance. Searching for valuable feed additives among by-products may promote not only circular economy, but also functional diets. Lignin from sugarcane bagasse was proposed as a potential prebiotic additive for chickens and incorporated at 1 % (w/w) in commercial chicken feed, tested in two feed forms, namely, mash and pellets. Physico-chemical characterization of both feed types with and without lignin was performed. Also, the prebiotic potential for feeds with lignin was assessed by an in vitro gastrointestinal model and evaluated the impact on chicken cecal Lactobacillus and Bifidobacterium. As for the pellet's physical quality, there was a higher cohesion of the pellets with lignin, indicating a higher resistance to breakout and lignin decreases the tendency of the pellets for microbial contamination. Regarding the prebiotic potential, mash feed with lignin showed higher promotion of Bifidobacterium in comparison with mash feed without lignin and to pellet feed with lignin. Lignin from sugarcane bagasse has prebiotic potential as additive to chicken feed when supplemented in mash feed diets, presenting itself as a sustainable and eco-friendly alternative to chicken feed additives supplementation.


Assuntos
Celulose , Saccharum , Animais , Lignina , Aves Domésticas , Prebióticos , Galinhas/microbiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Dieta , Grão Comestível
5.
Int J Biol Macromol ; 234: 123592, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36773873

RESUMO

Lignin has been suggested as a promising candidate for cosmetic applications due to its remarkable potential to absorb ultraviolet rays and distinctive antioxidant activity. This study aims at evaluating the performance of lignin from sugarcane bagasse (SCB) as natural UV blocker, antioxidant, and pigment. Lignin was extracted from SCB, characterized and incorporated into a blemish balm (BB) cream. The biological potential, concretely, in vitro and in vivo sun protection factor (SPF) and in vitro UVA-PF, and safety were assessed. A high-purity SCB lignin (>92 %) was obtained by a mild alkaline extraction process. The results of cytotoxicity, mutagenicity, skin sensitization and in vivo acute cutaneous irritation demonstrated that SCB lignin is safe for topical applications. Lignin showed capacity to scavenge both ABTS and DPPH radicals, which were preserved after its incorporation into the cosmetic formulation. Notable results were achieved in terms of in vitro and in vivo SPF of 9.5 ± 2.9 and 9.6 ± 0.8, respectively. Furthermore, the tested lignin-based BB cream revealed a broad-spectrum UV protection (critical wavelength of 378 ± 0.5 nm). These results suggest SCB lignin as multifunctional and safe ingredient for use in cosmetic products.


Assuntos
Cosméticos , Saccharum , Lignina/farmacologia , Lignina/química , Protetores Solares/química , Celulose , Pele , Cosméticos/farmacologia , Raios Ultravioleta , Antioxidantes/farmacologia , Antioxidantes/química
6.
Int J Biol Macromol ; 230: 123144, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36610579

RESUMO

This study evaluates the production of lignin bioactive extracts from sugarcane bagasse (SCB) and straw (SCS) alkaline black liquors using greener precipitating agents (methane sulfonic acid (MSA), formic acid (FA) and lactic acid (LA)) as replacers of sulfuric acid (SA), the most common one used in industry. Results showed that the highest precipitation yield was achieved by LA when applied to SCB (14.5 g extract/100 g SCB). Lignin SCB extracts were similar in composition in terms of total carbohydrates (61-70 %), lignin (22-30 %) and inorganics (1.6-2.6 %). Regarding the SCS extracts, similar yields were obtained among all extracts, however, differences in composition were observed between SA and greener precipitating agents, particularly in terms of sugar content. All extracts exhibited radical scavenging activity; overall the extracts were more effective in the scavenging of ABTS radical. FA was the most promising alternative to SA to recover lignin bioactive extracts. This work suggests organic acids as good candidates for obtaining valuable extracts from alkaline pulping of SCB and SCS instead of the conventional sulfuric acid.


Assuntos
Lignina , Saccharum , Celulose , Ácidos Sulfúricos , Extratos Vegetais , Hidrólise
7.
Stem Cell Rev Rep ; 19(1): 248-263, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36152233

RESUMO

Mesenchymal stem cells (MSCs) hold promising therapeutic potential in several clinical applications, mainly due to their paracrine activity. The implementation of future secretome-based therapeutic strategies requires the use of easily accessible MSCs sources that provide high numbers of cells with homogenous characteristics. MSCs obtained from induced pluripotent stem cells (iMSCs) have been put forward as an advantageous alternative to the gold-standard tissue sources, such as bone marrow (BM-MSCs). In this study, we aimed at comparing the secretome of BM-MSCs and iMSCs over long-term culture. For that, we performed a broad characterization of both sources regarding their identity, proteomic secretome analysis, as well as replicative senescence and associated phenotypes, including its effects on MSCs secretome composition and immunomodulatory action. Our results evidence a rejuvenated phenotype of iMSCs, which is translated into a superior proliferative capacity before the induction of replicative senescence. Despite this significant difference between iMSCs and BM-MSCs proliferation, both untargeted and targeted proteomic analysis revealed a similar secretome composition for both sources in pre-senescent and senescent states. These results suggest that shifting from the use of BM-MSCs to a more advantageous source, like iMSCs, may yield similar therapeutic effects as identified over the past years for this gold-standard MSC source.


Assuntos
Medula Óssea , Células-Tronco Mesenquimais , Diferenciação Celular , Proteômica , Secretoma , Senescência Celular
8.
Molecules ; 25(11)2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526879

RESUMO

Nowadays, the food sector is highly concerned with environmental issues and foreseen to develop strategies to reduce waste and losses resulting from activities developed in the food system. An approach is to increment added value to the agro-industrial wastes, which might provide economic growth and environmental protection, contributing to a circular economy. Mushroom by-products represent a disposal problem, but they are also promising sources of important compounds, which may be used due to their functional and nutritional properties. Research has been developed in different fields to obtain value added solutions for the by-products generated during mushroom production and processing. Bioactive compounds have been obtained and applied in the development of nutraceutical and pharmaceutical formulations. Additionally, other applications have been explored and include animal feed, fertilizer, bioremediation, energy production, bio-based materials, cosmetics and cosmeceuticals. The main purpose of this review is to highlight the relevant composition of mushroom by-products and discuss their potential as a source of functional compounds and other applications. Future research needs to explore pilot and industrial scale extraction methods to understand the technological feasibility and the economic sustainability of the bioactive compounds extraction and valorization towards different applications.


Assuntos
Agaricales/química , Antioxidantes/química , Suplementos Nutricionais/análise , Preparações Farmacêuticas/química , Resíduos/análise , Animais , Composição de Medicamentos , Humanos , Valor Nutritivo
9.
Molecules ; 25(5)2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32138318

RESUMO

This study aimed to develop new canned chub mackerel products incorporating edible seaweeds (Ascophyllum nodosum, Fucus spiralis, Saccorhiza polyschides, Chondrus crispus, Porphyra sp. and Ulva sp.) harvested in the Portuguese North-Central coast, with simultaneous sensory improvement and minerals enrichment. Two processes were compared, namely the addition of seaweeds in i) the canning step and ii) in the brining step (as the replacement for salt). The concentrations of four macrominerals (Na, K, Ca and Mg), chloride, and twelve trace elements (Co, Cu, Fe, I, Li, Mn, Mo, Rb, Se, Sr, V and Zn) were determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Results showed that canned chub mackerel incorporating C. crispus and F. spiralis was found to be the preferred sensory option, also exhibiting contents enriched with Cl, Co, Cu, Fe, I, Li, Mg, Mn, Mo, Na, Rb, Se, and Sr. This effect was more pronounced when both seaweed species were added to replace the salt added in the brining step.


Assuntos
Minerais/análise , Perciformes , Alga Marinha , Oligoelementos/análise , Animais , Espectrofotometria Atômica
10.
J Nerv Ment Dis ; 207(11): 951-957, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31503184

RESUMO

We explored the adherence to a home-delivered, computer-based, cognitive remediation protocol in a first-episode psychosis outpatient cohort. Seventeen patients underwent a cognitive training protocol for 6 months using an online platform accessible from their home under the supervision of a qualified neuropsychologist. Neuropsychological, psychopathological, and functional data were collected at baseline and postintervention, whereas qualitative appraisal of the intervention was assessed monthly. Overall, participants' evaluation of the program was positive. This was reflected in a good adherence rate with 12 (70%) of 17 patients completing 80% of the prescribed sessions. Exploratory analysis revealed significant improvements in sustained attention (p = 0.020) and verbal memory (p = 0.018). A decrease in negative symptoms and an improvement on the Clinical Global Impression were also found (p = 0.009). We believe these are encouraging results to further explore the adopted delivery approach, which could facilitate access to cognitive training earlier and to a larger group of patients.


Assuntos
Remediação Cognitiva/métodos , Intervenção Baseada em Internet , Internet , Transtornos Psicóticos/psicologia , Transtornos Psicóticos/terapia , Terapia Assistida por Computador/métodos , Adolescente , Adulto , Remediação Cognitiva/tendências , Feminino , Humanos , Internet/tendências , Intervenção Baseada em Internet/tendências , Masculino , Testes Neuropsicológicos , Projetos Piloto , Transtornos Psicóticos/diagnóstico , Terapia Assistida por Computador/tendências , Adulto Jovem
11.
Food Chem ; 269: 264-275, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100434

RESUMO

The total protein content and the (total and free) amino acid composition of nine edible species of red, brown and green seaweeds collected in the Portuguese North-Central coast were quantified to assess their potential contribution to the recommended dietary intake. Whenever possible, the protein and amino acid composition was compared with that of commercial European seaweeds. The protein content was the highest (P < 0.05) in red species (19.1-28.2 g/100 g dw), followed by the green seaweed Ulva spp. (20.5-23.3 g/100 g dw), with the lowest content found in brown seaweeds (6.90-19.5 g/100 g dw). Brown seaweeds presented the lowest mean contents of essential amino acids (EAAs) (41.0% protein) but significantly (P < 0.05) higher concentrations of non-essential amino acids (36.1% protein) and free amino acids (6.47-24.0% protein). Tryptophan, methionine and leucine were the limiting EAAs in all species. In contrast, lysine was found in high concentrations, especially in red (2.71-3.85% protein) and green (2.84-4.24% protein) seaweeds.


Assuntos
Aminoácidos/análise , Alga Marinha/química , Proteínas , Ulva/química
12.
Biochemistry ; 56(36): 4860-4870, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28799326

RESUMO

Glucagon-like peptide 1 (GLP-1) is a small incretin hormone stimulated by food intake, resulting in an amplification of the insulin response. Though GLP-1 is interesting as a drug candidate for the treatment of type 2 diabetes mellitus, its short plasma half-life of <3 min limits its clinical use. A strategy for extending the half-life of GLP-1 utilizes the long half-life of human serum albumin (HSA) by combining the two via chemical conjugation or genetic fusion. HSA has a plasma half-life of around 21 days because of its interaction with the neonatal Fc receptor (FcRn) expressed in endothelial cells of blood vessels, which rescues circulating HSA from lysosomal degradation. We have conjugated GLP-1 to C34 of native sequence recombinant HSA (rHSA) and two rHSA variants, one with increased and one with decreased binding affinity for human FcRn. We have investigated the impact of conjugation on FcRn binding affinities, GLP-1 potency, and pharmacokinetics, combined with the solution structure of the rHSA variants and GLP-1-albumin conjugates. The solution structures, determined by small-angle X-ray scattering, show the GLP-1 pointing away from the surface of rHSA. Combining the solution structures with the available structural information about the FcRn and GLP-1 receptor obtained from X-ray crystallography, we can explain the observed in vitro and in vivo behavior. We conclude that the conjugation of GLP-1 to rHSA does not affect the interaction between rHSA and FcRn, while the observed decrease in the potency of GLP-1 can be explained by a steric hindrance of binding of GLP-1 to its receptor.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/química , Antígenos de Histocompatibilidade Classe I/química , Receptores Fc/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/farmacocinética , Albumina Sérica/química , Animais , Ligação Competitiva , Feminino , Meia-Vida , Humanos , Camundongos , Ligação Proteica , Conformação Proteica , Estabilidade Proteica
13.
J Biol Chem ; 292(32): 13312-13322, 2017 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-28637874

RESUMO

Albumin is the most abundant plasma protein involved in the transport of many compounds, such as fatty acids, bilirubin, and heme. The endothelial cellular neonatal Fc receptor (FcRn) has been suggested to play a central role in maintaining high albumin plasma levels through a cellular recycling pathway. However, direct mapping of this process is still lacking. This work presents the use of wild-type and engineered recombinant albumins with either decreased or increased FcRn affinity in combination with a low or high FcRn-expressing endothelium cell line to clearly define the FcRn involvement, intracellular pathway, and kinetics of albumin trafficking by flow cytometry, quantitative confocal microscopy, and an albumin-recycling assay. We found that cellular albumin internalization was proportional to FcRn expression and albumin-binding affinity. Albumin accumulation in early endosomes was independent of FcRn-binding affinity, but differences in FcRn-binding affinities significantly affected the albumin distribution between late endosomes and lysosomes. Unlike albumin with low FcRn-binding affinity, albumin with high FcRn-binding affinity was directed less to the lysosomes, suggestive of FcRn-directed albumin salvage from lysosomal degradation. Furthermore, the amount of recycled albumin in cell culture media corresponded to FcRn-binding affinity, with a ∼3.3-fold increase after 1 h for the high FcRn-binding albumin variant compared with wild-type albumin. Together, these findings uncover an FcRn-dependent endosomal cellular-sorting pathway that has great importance in describing fundamental mechanisms of intracellular albumin recycling and the possibility to tune albumin-based therapeutic effects by FcRn-binding affinity.


Assuntos
Endossomos/metabolismo , Endotélio Vascular/metabolismo , Lisossomos/metabolismo , Microvasos/metabolismo , Receptores Fc/agonistas , Albumina Sérica/metabolismo , Substituição de Aminoácidos , Linhagem Celular Transformada , Microanálise por Sonda Eletrônica , Endossomos/ultraestrutura , Endotélio Vascular/citologia , Endotélio Vascular/ultraestrutura , Corantes Fluorescentes , Regulação da Expressão Gênica , Variação Genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Radioisótopos do Iodo , Cinética , Lisossomos/ultraestrutura , Microscopia Confocal , Microvasos/citologia , Microvasos/ultraestrutura , Engenharia de Proteínas , Transporte Proteico , Receptores Fc/genética , Receptores Fc/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/metabolismo , Albumina Sérica/genética
14.
Actas esp. psiquiatr ; 45(2): 56-61, mar.-abr. 2017. tab
Artigo em Espanhol | IBECS | ID: ibc-161749

RESUMO

La Escala de Valoración de Síntomas Psicóticos (PSYRATS) es una herramienta de evaluación clínica que se centra en la medición detallada de delirios y alucinaciones en pacientes con psicosis. El objetivo de este estudio fue examinar las propiedades psicométricas de la versión en portugués de la PSYRATS. Se evaluó una muestra de 92 pacientes ambulatorios con la PSYRATS y la Escala de Síndromes Positivo y Negativo (PANSS). Los pacientes padecían de esquizofrenia o trastornos esquizoafectivos y presentaban síntomas psicóticos persistentes. Se encontró una buena fiabilidad entre evaluadores, fiabilidad de repetibilidad, validez concurrente y consistencia interna. El análisis factorial de los ítems de la escala de alucinaciones auditivas reveló una solución de cuatro factores: características de la emoción y factor de perturbación (factor 1), un factor de características físicas (factor 2), un factor de características de control (factor 3) y un factor de atribución cognitiva (factor 4). En cuanto a los ítems de la escala de delirios, se encontró una solución de dos factores: un factor de interpretación cognitiva y perturbación (factor 1) y un factor de características emocionales (factor 2). La versión en portugués de la PSYRATS replicó parcialmente resultados publicados anteriormente en otros países


The Psychotic Symptom Rating Scales (PSYRATS) is a clinical assessment tool that focuses on the detailed measurement of delusions and hallucinations in patients with psychosis. The goal of this study was to examine the psychometric properties of the Portuguese version of the PSYRATS. A sample of 92 outpatients suffering from schizophrenia or schizoaffective disorders and presenting persistent psychotic symptoms was assessed using the PSYRATS and the Positive and Negative Syndrome Scale (PANSS). Good inter-rater reliability, test-retest reliability, concurrent validity and internal consistency were found. Factor analysis of the auditory hallucinations scale items disclosed a four-factor solution: emotion characteristics and disruption factor (factor 1), a physical characteristics factor (factor 2), a control characteristics factor (factor 3) and a cognitive attribution factor (factor 4). Regarding the delusions scale items, a two-factor solution was found: cognitive interpretation and disruption factor (factor 1) and an emotional characteristics (factor 2). The Portuguese version of the PSYRATS partially replicates previously published results in other countries


Assuntos
Humanos , Transtornos Psicóticos/classificação , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Esquizofrenia/diagnóstico , Psicometria/instrumentação , Reprodutibilidade dos Testes , Reprodutibilidade dos Testes , Alucinações/diagnóstico , Delusões/diagnóstico , Transtornos Psicóticos/diagnóstico
15.
Actas Esp Psiquiatr ; 45(2): 56-61, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28353290

RESUMO

The Psychotic Symptom Rating Scales (PSYRATS) is a clinical assessment tool that focuses on the detailed measurement of delusions and hallucinations in patients with psychosis. The goal of this study was to examine the psychometric properties of the Portuguese version of the PSYRATS. A sample of 92 outpatients suffering from schizophrenia or schizoaffective disorders and presenting persistent psychotic symptoms was assessed using the PSYRATS and the Positive and Negative Syndrome Scale (PANSS). Good inter-rater reliability, test-retest reliability, concurrent validity and internal consistency were found. Factor analysis of the auditory hallucinations scale items disclosed a four-factor solution: emotion characteristics and disruption factor (factor 1), a physical characteristics factor (factor 2), a control characteristics factor (factor 3) and a cognitive attribution factor (factor 4). Regarding the delusions scale items, a two-factor solution was found: cognitive interpretation and disruption factor (factor 1) and an emotional characteristics (factor 2). The Portuguese version of the PSYRATS partially replicates previously published results in other countries.


Assuntos
Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/diagnóstico , Adulto , Feminino , Humanos , Masculino , Psicometria , Traduções
16.
Front Psychol ; 7: 1642, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27877142

RESUMO

In psychiatric classifications, hallucinations (mainly auditory hallucinations) are one of the fundamental criteria for establishing a schizophrenia diagnosis or any of the related psychotic disorder's diagnoses. The conceptual proximity between delusions and hallucinations was maintained until the end of the XIX century, with several supporters during the XX century. Their limits were not yet definitely defined in terms of Descriptive Psychopathology, and much less so in terms of biochemical and anatomical models. In this article we aimed to analyse the dimensions of both hallucinations and delusions in a sample of patients with schizophrenia and schizoaffective disorder. We also intend to find the determinants of the main dimensions of hallucinations. One hundred patients with schizophrenia (80) or schizoaffective disorder (20), 64% males, mean age 39.75, from the outpatient and inpatient units of the Psychiatry Department of Hospital de Santa Maria and the Centro Hospitalar Psiquiátrico de Lisboa were assessed by means of the Psychotic Symptom Rating Scales (PSYRATS) and a structured interview. In this study we designed an empirical based model by means of bivariate Spearman's rank correlation coefficient, and multivariate statistics (linear regression and multiple multivariate linear regression), where the main dimensions of hallucinations are determined by the central dimensions of delusions.

17.
J Control Release ; 223: 22-30, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26699424

RESUMO

Human serum albumin (HSA) is a natural carrier protein possessing multiple ligand binding sites with a plasma half-life ~19days, facilitated by interaction with the human neonatal Fc receptor (FcRn), that promotes it as a highly attractive drug delivery technology. A lack of adequate rodent models, however, is a major challenge in the preclinical development of albumin-linked therapeutics. This work describes the first double transgenic mouse model bearing both human FcRn and HSA genes (hFcRn(+/+), hAlb(+/+)) under the control of an endogenous promoter. Human FcRn was shown by immunohistochemical and qPCR analysis to be ubiquitously expressed in the major organs. Physiological levels of HSA were detected in the blood that exhibited similar FcRn binding kinetics to recombinant or human serum-derived HSA. The circulatory half-life (t1/2) was shown to be dependent on FcRn binding affinity that increased from low affinity (t1/2 29h), to wild type (t1/2 50h), to high affinity (t1/2 80h) variants, that validates the application of the model for optimizing the pharmacokinetics of drug carriers who's circulatory half-life is dependent in some manner upon interaction with endogenous FcRn. This study presents a novel mouse model that better mimics the human physiological conditions and, thus, has potential wide applications in the development of albumin-linked drugs or conventional drugs whose action is influenced by reversible binding to endogenous HSA.


Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Receptores Fc/genética , Receptores Fc/metabolismo , Albumina Sérica/genética , Albumina Sérica/metabolismo , Animais , Feminino , Imunoglobulina G/metabolismo , Mucosa Intestinal/metabolismo , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Preparações Farmacêuticas/metabolismo , Ligação Proteica
18.
J Biol Chem ; 289(19): 13492-502, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24652290

RESUMO

A major challenge for the therapeutic use of many peptides and proteins is their short circulatory half-life. Albumin has an extended serum half-life of 3 weeks because of its size and FcRn-mediated recycling that prevents intracellular degradation, properties shared with IgG antibodies. Engineering the strictly pH-dependent IgG-FcRn interaction is known to extend IgG half-life. However, this principle has not been extensively explored for albumin. We have engineered human albumin by introducing single point mutations in the C-terminal end that generated a panel of variants with greatly improved affinities for FcRn. One variant (K573P) with 12-fold improved affinity showed extended serum half-life in normal mice, mice transgenic for human FcRn, and cynomolgus monkeys. Importantly, favorable binding to FcRn was maintained when a single-chain fragment variable antibody was genetically fused to either the N- or the C-terminal end. The engineered albumin variants may be attractive for improving the serum half-life of biopharmaceuticals.


Assuntos
Albuminas/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Receptores Fc/metabolismo , Albuminas/genética , Albuminas/farmacologia , Substituição de Aminoácidos , Animais , Feminino , Meia-Vida , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/farmacologia , Humanos , Macaca fascicularis , Camundongos , Mutação de Sentido Incorreto , Receptores Fc/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia
19.
Nat Immunol ; 15(2): 168-76, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24413774

RESUMO

STAT1 is an indispensable component of a heterotrimer (ISGF3) and a STAT1 homodimer (GAF) that function as transcription regulators in type 1 and type 2 interferon signaling, respectively. To investigate the importance of STAT1-cooperative DNA binding, we generated gene-targeted mice expressing cooperativity-deficient STAT1 with alanine substituted for Phe77. Neither ISGF3 nor GAF bound DNA cooperatively in the STAT1F77A mouse strain, but type 1 and type 2 interferon responses were affected differently. Type 2 interferon-mediated transcription and antibacterial immunity essentially disappeared owing to defective promoter recruitment of GAF. In contrast, STAT1 recruitment to ISGF3 binding sites and type 1 interferon-dependent responses, including antiviral protection, remained intact. We conclude that STAT1 cooperativity is essential for its biological activity and underlies the cellular responses to type 2, but not type 1 interferon.


Assuntos
Interferon Tipo I/metabolismo , Interferon gama/metabolismo , Proteínas Mutantes/metabolismo , Fator de Transcrição STAT1/metabolismo , Animais , Células Cultivadas , DNA/metabolismo , Fator Gênico 3 Estimulado por Interferon/metabolismo , Listeriose/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Mutantes/genética , Ligação Proteica/genética , Engenharia de Proteínas , Fator de Transcrição STAT1/genética , Transdução de Sinais/genética , Transgenes/genética , Vírus da Estomatite Vesicular Indiana
20.
Eur J Pharm Biopharm ; 83(3): 427-35, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23159710

RESUMO

In vitro cell culture models for studying oral drug absorption during early stages of drug development have become a useful tool in drug discovery and development, with respect to substance throughput and reproducibility. The aim of this study was to establish an in vitro cellular model based on human colon carcinoma Caco-2, mucus-producing HT29, and Raji B cells in order to design a model that more accurately mimics the small intestinal epithelial layer. Normal oriented model was set up by seeding co-cultures of Caco-2 and HT29 cells into Transwell filters and maintained under identical conditions following addition of Raji B to the basolateral chamber. Inverted model was set up seeding Caco-2 and HT29 cells on the basolateral chamber and then transferred in the Transwell device with the epithelial cells facing the basolateral chamber following Raji B addition to the apical compartment. Morphological differences on size and thickness of cell membranes were detected between the models studied by using fluorescence microscopy. On the triple co-culture models, cell membranes were increasing in size and thickness from the Caco-2 to Caco-2/HT29 and Caco-2/Raji B. Also, the nuclei seem to be larger than in the other studied models. Insulin permeation was higher on the triple co-culture model when compared to the Caco-2/HT29 co-culture model. Also, insulin permeation as mediated by nanoparticles and insulin solution permeation was higher on the normal oriented Caco-2/HT29/Raji B model as compared to the inverted model. Overall, our results suggest that Caco-2/HT29/Raji B triple co-culture normal oriented cellular model may be reliable to obtain a more physiological, functional, and reproducible in vitro model of the intestinal barrier to study protein absorption, both in solution and when delivered by nanocarriers.


Assuntos
Absorção Intestinal , Modelos Biológicos , Peptídeos/farmacocinética , Células CACO-2 , Técnicas de Cocultura , Células HT29 , Humanos , Microscopia de Fluorescência , Permeabilidade
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