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1.
BMC Psychol ; 11(1): 407, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990335

RESUMO

BACKGROUND: Compulsivity is the hallmark of addiction progression and, as a construct, has played an important role in unveiling the etiological pathways from learning mechanisms underlying addictive behavior to harms resulting from it. However, a sound use of the compulsivity construct in the field of behavioral addictions has been hindered to date by the lack of consensus regarding its definition and measurement. Here we capitalize on a previous systematic review and expert appraisal to develop a compulsivity scale for candidate behavioral addictions (the Granada Assessment for Cross-domain Compulsivity, GRACC). METHODS: The initial scale (GRACC90) consisted of 90 items comprising previously proposed operationalizations of compulsivity, and was validated in two panel samples of individuals regularly engaging in gambling and video gaming, using exploratory structural equation modeling (ESEM) and convergence analyses. RESULTS: The GRACC90 scale is unidimensional and structurally invariant across samples, and predicted severity of symptoms, lower quality of life, and negative affect, to similar degrees in the two samples. Additionally, poorer quality of life and negative affect were comparably predicted by compulsivity and by severity of symptoms. A shorter version of the scale (GRACC18) is proposed, based on selecting the 18 items with highest factor loadings. CONCLUSIONS: Results support the proposal that core symptoms of behavioral addictions strongly overlap with compulsivity, and peripheral symptoms are not essential for their conceptualization. Further research should clarify the etiology of compulsive behavior, and whether pathways to compulsivity in behavioral addictions could be common or different across domains.


Assuntos
Comportamento Aditivo , Jogo de Azar , Jogos de Vídeo , Humanos , Qualidade de Vida , Comportamento Compulsivo
2.
J Clin Med ; 12(18)2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37762941

RESUMO

BACKGROUND: Necrotizing fasciitis (NF) is a serious infectious disease that can initially place the patient's life in danger and, after successful surgical and antibiotic treatment, leaves extensive wounds with sometimes even exposed bones and tendons. Autologous skin grafts are not always possible or require adequate wound bed preparation. Novel intact fish skin grafts (iFSGs; Kerecis® Omega3 Wound, Kerecis hf, Isafjördur, Iceland) have already shown their potential to promote granulation in many other wound situations. Faster wound healing rates and better functional and cosmetic outcomes were observed due to their additionally postulated anti-inflammatory and analgesic properties. Therefore, iFSGs may also be essential in treating NF. We present our initial experience with iFSGs in treating leg wounds after NF and review the literature for the current spectrum of clinical use of iFSGs. CASE PRESENTATIONS: We present two male patients (aged 60 and 69 years) with chronic or acute postsurgical extensive leg ulcers six weeks and six days after necrotizing fasciitis, respectively. Both suffered from diabetes mellitus without vascular pathologies of the lower limbs. A single application of one pre-meshed (Kerecis® Graftguide) and one self-meshed 300 cm2 iFSG (Kerecis® Surgiclose) was performed in our operation room after extensive surgical debridement and single circles of negative wound pressure therapy. Application and handling were easy. An excellent wound granulation was observed, even in uncovered tibia bone and tendons, accompanied by pain relief in both patients. Neither complications nor allergic reactions occurred. The patients received autologous skin grafting with excellent functional and cosmetic outcomes. CONCLUSIONS: iFSGs have the potential to play a significant role in the future treatment of NF due to the fast promotion of wound granulation and pain relief. Our experience may encourage surgeons to use iFSGs in NF patients, although high-quality, large-sized studies are still required to confirm these results. The observed effects of iFSGs on wounds associated with NF may be transferred to other wound etiologies as well.

3.
Cells ; 11(15)2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35954160

RESUMO

The myosin light chain phosphatase target subunit 1 (MYPT1), encoded by the PPP1R12A gene, is a key component of the myosin light chain phosphatase (MLCP) protein complex. MYPT1 isoforms have been described as products of the cassette-type alternative splicing of exons E13, E14, E22, and E24. Through in silico analysis of the publicly available EST and mRNA databases, we established that PPP1R12A contains 32 exons (6 more than the 26 previously reported), of which 29 are used in 11 protein-coding transcripts. An in silico analysis of publicly available RNAseq data combined with validation by reverse transcription (RT)-PCR allowed us to determine the relative abundance of each transcript in three cell types of the circulatory system where MYPT1 plays important roles: human umbilical vein endothelial cells (HUVEC), human saphenous vein smooth muscle cells (HSVSMC), and platelets. All three cell types express up to 10 transcripts at variable frequencies. HUVECs and HSVSMCs predominantly express the full-length variant (58.3% and 64.3%, respectively) followed by the variant skipping E13 (33.7% and 23.1%, respectively), whereas in platelets the predominant variants are those skipping E14 (51.4%) and E13 (19.9%), followed by the full-length variant (14.4%). Variants including E24 account for 5.4% of transcripts in platelets but are rare (<1%) in HUVECs and HSVSMCs. Complex transcriptional profiles were also found across organs using in silico analysis of RNAseq data from the GTEx project. Our findings provide a platform for future studies investigating the specific (patho)physiological roles of understudied MYPT1 isoforms.


Assuntos
Sistema Cardiovascular , Fosfatase de Miosina-de-Cadeia-Leve/genética , Transcrição Reversa , Sistema Cardiovascular/metabolismo , Células Endoteliais/metabolismo , Humanos , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Reação em Cadeia da Polimerase , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
4.
Life (Basel) ; 12(8)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-36013311

RESUMO

Cognitive behavioral therapy (CBT) packages for anxiety disorders, such as phobias, usually include gradual exposure to anxious contexts, positive self-verbalizations, and relaxation breathing. The objective of this research was to analyze the specific neural activation produced by the self-verbalizations (S) and breathing (B) included in CBT. Thirty participants with clinical levels of a specific phobia to small animals were randomly assigned to three fMRI conditions in which individuals were exposed to phobic stimuli in real images: a group underwent S as a technique to reduce anxiety; a second group underwent B; and a control group underwent exposure only (E). Simple effects showed higher brain activation comparing E > S, E > B, and S > B. In particular, in the E group, compared to the experimental conditions, an activation was observed in sensory-perceptive and prefrontal and in other regions involved in the triggering of emotion (i.e., amygdala, supplementary motor area, and cingulate gyrus) as well as an activation associated with interoceptive sensitivity (i.e., insula and cingulate cortex). According to the specific tool used, discrepancies in the neural changes of CBT efficacy were observed. We discuss the theoretical implications according to the dual model of CBT as a set of therapeutic tools that activate different processes.

5.
Life (Basel) ; 13(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36676068

RESUMO

The objective of this study was to analyze the neurostructural abnormalities of brain areas responsible for the acquisition and maintenance of fear in small animal phobia by comparing gray matter volume (GMV) in individuals with phobia and non-fearful controls. Structural magnetic resonance imaging was obtained from 62 adults (79% female) assigned to one of two groups: 31 were diagnosed with small animal phobia and 31 were non-fearful controls. To investigate structural alterations, a whole-brain voxel-based morphometry analysis was conducted to compare the GMV of the brain areas involved in fear between both groups. The results indicated that individuals with a small animal specific phobia showed smaller GMV in cortical regions, such as the orbitofrontal (OFC) and medial frontal cortex, and greater GMV in the putamen than non-fearful controls. These brain areas are responsible for avoidant behavior (putamen) and emotional regulation processes or inhibitory control (prefrontal cortex (PFC)), which might suggest a greater vulnerability of phobic individuals to acquiring non-adaptive conditioned responses and emotional dysregulation. The findings provide preliminary support for the involvement of structural deficits in OFC and medial frontal cortex in phobia, contributing to clarify the neurobiological substrates for phobias.

6.
Small GTPases ; 13(1): 239-254, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34565293

RESUMO

GTP binding proteins known as small GTPases make up one of the largest groups of regulatory proteins and control almost all functions of living cells. Their activity is under, respectively, positive and negative regulation by guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs), which together with their upstream regulators and the downstream targets of the small GTPases form formidable signalling networks. While genomics has revealed the large size of the GTPase, GEF and GAP repertoires, only a small fraction of their interactions and functions have yet been experimentally explored. Dictyostelid social amoebas have been particularly useful in unravelling the roles of many proteins in the Rac-Rho and Ras-Rap families of GTPases in directional cell migration and regulation of the actin cytoskeleton. Genomes and cell-type specific and developmental transcriptomes are available for Dictyostelium species that span the 0.5 billion years of evolution of the group from their unicellular ancestors. In this work, we identified all GTPases, GEFs and GAPs from genomes representative of the four major taxon groups and investigated their phylogenetic relationships and evolutionary conservation and changes in their functional domain architecture and in their developmental and cell-type specific expression. We performed a hierarchical cluster analysis of the expression profiles of the ~2000 analysed genes to identify putative interacting sets of GTPases, GEFs and GAPs, which highlight sets known to interact experimentally and many novel combinations. This work represents a valuable resource for research into all fields of cellular regulation.


Assuntos
Dictyostelium , Proteínas Monoméricas de Ligação ao GTP , Dictyostelium/genética , Dictyostelium/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Filogenia
7.
Front Immunol ; 12: 766272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912339

RESUMO

Bacterial infections are a major cause of morbidity and mortality in chronic lymphocytic leukemia (CLL), and infection risk increases in patients treated with the Bruton's tyrosine kinase (Btk) inhibitor, ibrutinib. Btk and related kinases (like Tec) are expressed in non-leukemic hematopoietic cells and can be targeted by ibrutinib. In platelets, ibrutinib therapy is associated with bleeding complications mostly due to off-target effects. But the ability of platelets to respond to bacteria in CLL, and the potential impact of ibrutinib on platelet innate immune functions remain unknown. FcγRIIA is a tyrosine kinase-dependent receptor critical for platelet activation in response to IgG-coated pathogens. Crosslinking of this receptor with monoclonal antibodies causes downstream activation of Btk and Tec in platelets, however, this has not been investigated in response to bacteria. We asked whether ibrutinib impacts on FcγRIIA-mediated activation of platelets derived from CLL patients and healthy donors after exposure to Staphylococcus aureus Newman and Escherichia coli RS218. Platelet aggregation, α-granule secretion and integrin αIIbß3-dependent scavenging of bacteria were detected in CLL platelets but impaired in platelets from ibrutinib-treated patients and in healthy donor-derived platelets exposed to ibrutinib in vitro. While levels of surface FcγRIIA remained unaffected, CLL platelets had reduced expression of integrin αIIbß3 and GPVI compared to controls regardless of therapy. In respect of intracellular signaling, bacteria induced Btk and Tec phosphorylation in both CLL and control platelets that was inhibited by ibrutinib. To address if Btk is essential for platelet activation in response to bacteria, platelets derived from X-linked agammaglobulinemia patients (lacking functional Btk) were exposed to S. aureus Newman and E. coli RS218, and FcγRIIA-dependent aggregation was observed. Our data suggest that ibrutinib impairment of FcγRIIA-mediated platelet activation by bacteria results from a combination of Btk and Tec inhibition, although off-target effects on additional kinases cannot be discarded. This is potentially relevant to control infection-risk in CLL patients and, thus, future studies should carefully evaluate the effects of CLL therapies, including Btk inhibitors with higher specificity for Btk, on platelet-mediated immune functions.


Assuntos
Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Plaquetas/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de IgG/imunologia , Adenina/farmacologia , Adenina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Plaquetas/imunologia , Escherichia coli , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Leucemia Linfocítica Crônica de Células B/imunologia , Masculino , Pessoa de Meia-Idade , Piperidinas/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Pirazinas/farmacologia , Staphylococcus aureus
8.
ACS Pharmacol Transl Sci ; 4(5): 1567-1577, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34661075

RESUMO

Protein arginine methyltransferases (PRMTs) catalyze the transfer of methyl groups to arginine residues in proteins. PRMT inhibitors are novel, promising drugs against cancer that are currently in clinical trials, which include oral administration of the drugs. However, off-target activities of systemically available PRMT inhibitors have not yet been investigated. In this work, we study the relevance of arginine methylation in platelets and investigate the effect of PRMT inhibitors on platelet function and on the expression of relevant platelet receptors. We show that (1) key platelet proteins are modified by arginine methylation; (2) incubation of human platelets with PRMT inhibitors for 4 h results in impaired capacity of platelets to aggregate in response to thrombin and collagen, with IC50 values in the µM range; and (3) treatment with PRMT inhibitors leads to decreased membrane expression and reduced activation of the critical platelet integrin αIIbß3. Our contribution opens new avenues for research on arginine methylation in platelets, including the repurposing of arginine methylation inhibitors as novel antiplatelet drugs. We also recommend that current and future clinical trials with PRMT inhibitors consider any adverse effects associated with platelet inhibition of these emerging anticancer drugs.

9.
J Clin Med ; 10(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34441804

RESUMO

BACKGROUND: Cognitive-behavioral therapy (CBT) with exposure is the treatment of choice for specific phobia. Virtual reality exposure therapy (VRET) has shown benefits for the treatment and prevention of the return of fear in specific phobias by addressing the therapeutic limitations of exposure to real images. METHOD: Thirty-one participants with specific phobias to small animals were included: 14 were treated with CBT + VRET (intervention group), and 17 were treated with CBT + exposure to real images (active control group). Participants' scores in anxiety and phobia levels were measured at baseline, post-treatment, and 3-month follow-up, and brain activation was measured through functional magnetic resonance imaging (fMRI) baseline and post-treatment. RESULTS: Both groups showed a significant decrease in anxiety and phobia scores after the therapy and were maintained until follow-up. There were no significant differences between both groups. Overall, fMRI tests showed a significant decrease in brain activity after treatment in some structures (e.g., prefrontal and frontal cortex) and other structures (e.g., precuneus) showed an increasing activity after therapy. However, structures such as the amygdala remained active in both groups. CONCLUSIONS: The efficacy of CBT + VRET was observed in the significant decrease in anxiety responses. However, the results of brain activity observed suggest that there was still a fear response in the brain, despite the significant decrease in subjective anxiety levels.

10.
Life (Basel) ; 11(4)2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810230

RESUMO

Brain regions involved in small-animal phobia include subcortical and cortical areas. The present study explored the neuronal correlates of small-animal phobia through fMRI data to determine whether a manipulation of number and proximity parameters affects the neurobiology of the processing of feared stimuli. The participants were 40 individuals with phobia and 40 individuals without phobia (28.7% male and 71.3% female). They watched videos of real and virtual images of spiders, cockroaches and lizards in motion presented more or less nearby with one or three stimuli in the different conditions. The results suggested a differential brain activity between participants with and without phobia depending on the proximity and number of phobic stimuli. Proximity activated the motor response marked by the precentral gyrus and the cingulate gyrus. By contrast, the number of stimuli was associated with significant sensory activity in the postcentral gyrus and ventromedial prefrontal cortex. We also observed a greater activity in the occipital cortex when exploring the number compared to the proximity factor. Threatening stimuli presented nearby and those presented in greater numbers generated an intense phobic response, suggesting a different emotion regulation strategy. Based on these findings, exposure therapies might consider including proximity to the threat and number of stimuli as key factors in treatment.

11.
Foods ; 10(3)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668279

RESUMO

Overripe seeds from sun-dried grapes submitted to postharvest dehydration constitute a scarcely investigated class of vinification byproduct with limited reports on their phenolic composition and industrial applications. In this study, Raman spectroscopy was applied to characterize a selection of overripe seed byproducts from different white grapes (cv. Moscatel, cv. Pedro Ximénez and cv. Zalema) submitted to postharvest sun drying. The Raman measurements were taken using a 1064 nm excitation laser in order to mitigate the fluorescent effect and the dispersive detection scheme allowed a compactness of the optical system. Spectroscopic data were processed by a principal component analysis to reduce the dimensionality and partner recognition. The evolution of the Raman spectrum during the overripening process was compared with the phenolic composition of grape seeds, which was determined by rapid resolution liquid chromatography/mass spectrometry (RRLC/MS). A multivariate processing of the spectroscopic data allowed the classification of overripe seeds according to the grape variety and the monitoring of stages of the postharvest sun drying process.

12.
Food Chem ; 346: 128919, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33418420

RESUMO

The post-fermentative double addition of Pedro Ximénez cv seeds obtained from natural matured grapes (ripe seeds, RS) and postharvest sun-dried grapes (overripe seeds, OS) were studied as sustainable enological alternatives to conventional vinification (CW) to improve the stability of Syrah wines produced in a warm climate. The phenolic composition was assessed by rapid resolution liquid chromatography, copigmentation/polymerization processes by spectrophotometry, and color quality and stability by Differential Colorimetry. OSW and RSW wines enriched their total phenolic content, being the effect more pronounced with overripe seeds (by 23% versus 10%). OSW differences were found for gallic acid, monomeric flavan-3-ols, and procyanidins compared to CW, and for (+)-catechin, procyanidin B2-3-O-gallate and the tetramer to RSW. Phenolic changes were related to higher color intensity in seed-added wines. OSW having higher percentage of polymeric pigments maintained for longer time the chromatic improvement, being visually darker and more intense than final CW and RSW.


Assuntos
Clima , Cor , Fermentação , Fenóis/análise , Vinho/análise , Sementes/química , Vitis/química
13.
Rev. neurol. (Ed. impr.) ; 71(11): 391-398, 1 dic., 2020. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-198938

RESUMO

INTRODUCCIÓN: La evidencia disponible recoge resultados consistentes sobre cambios cerebrales morfológicos y funcionales producidos por el tratamiento psicológico. La terapia cognitivo-conductual (TCC) de exposición es actualmente el tratamiento psicológico más eficaz para las fobias. OBJETIVOS: Explorar los cambios cerebrales y autoinformados en pacientes con fobias específicas a animales pequeños sometidos a un programa de TCC de exposición y comprobar si el programa consiguió que estos pacientes procesaran los estímulos temidos de manera similar a las personas no fóbicas. Sujetos y métodos. La muestra estuvo compuesta por 32 adultos, de los que 16 (5 hombres y 11 mujeres; edad media: 38,08 años) tenían un diagnóstico de fobia específica a animales pequeños y 16 (4 hombres y 12 mujeres; edad media: 21,81 años) no tenían dicho diagnóstico. Se utilizó un diseño univariado de tratamiento antes-después. Las puntuaciones del grupo sin fobia en autoinformes y activación cerebral se compararon con las puntuaciones del grupo con fobia posteriores al tratamiento. RESULTADOS: Los datos muestran cambios significativos en la actividad cerebral y mejoras en las medidas autoinformadas debido a la aplicación de la TCC a la fobia específica. Tras recibir TCC, los participantes mostraron una mayor activación en puntos del precúneo. Además, comparado con los participantes sin fobia, los pacientes fóbicos mantenían las respuestas defensivas y de miedo ante los estímulos fóbicos. CONCLUSIONES: El precúneo parece ser un regulador que reorganiza el procesamiento de los estímulos fóbicos. Puede implicar que la TCC de exposición, además, activa mecanismos de aceptación, autoconciencia y autoeficacia


INTRODUCTION. The current evidence collected consistent results about morphological and functional brain changes produced by psychological treatment. Exposure cognitive-behavioral therapy (CBT) is currently the most effective psychological treatment for phobias. AIMS. To explore the brain activation and self-reported changes in patients with specific phobias to small animals who underwent a CBT exposure program and to prove if the CBT program made phobic patients process feared stimuli similarly to non-phobic persons. SUBJECTS AND METHODS. The sample consisted of 32 adults, of which 16 (5 males and 11 females; mean age: 38.08) had specific phobia to small animals and 16 (4 males and 12 females; mean age: 21.81) had no phobias. A univariate before-and-after treatment design were used. In addition, the scores of the non-phobic group in self-reports and brain activity were compared with the post-treatment scores of the phobic group. RESULTS. Data show significant changes in brain activity, and improvements in self-reported measures because of applying CBT to specific phobias. As a highlight, participants showed a greater activation in points of the precuneus after receiving CBT. Also, when compared with non-phobic participants, phobic patients still remain with both fear and defensive responses to phobic stimuli. CONCLUSIONS. The precuneus seems to be a regulator that reorganizes the processing of phobic stimuli. It can imply as CBT/ exposure also active acceptance, self-awareness, and self-efficacy mechanisms


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Transtornos Fóbicos/fisiopatologia , Transtornos Fóbicos/terapia , Terapia Cognitivo-Comportamental/métodos , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Imageamento por Ressonância Magnética/métodos , Autorrelato , Resultado do Tratamento
15.
Int J Mol Sci ; 21(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948107

RESUMO

Remodeling of the actin cytoskeleton is one of the critical events that allows platelets to undergo morphological and functional changes in response to receptor-mediated signaling cascades. Coronins are a family of evolutionarily conserved proteins implicated in the regulation of the actin cytoskeleton, represented by the abundant coronins 1, 2, and 3 and the less abundant coronin 7 in platelets, but their functions in these cells are poorly understood. A recent report revealed impaired agonist-induced actin polymerization and cofilin phosphoregulation and altered thrombus formation in vivo as salient phenotypes in the absence of an overt hemostasis defect in vivo in a knockout mouse model of coronin 1. Here we show that the absence of coronin 1 is associated with impaired translocation of integrin ß2 to the platelet surface upon stimulation with thrombin while morphological and functional alterations, including defects in Arp2/3 complex localization and cAMP-dependent signaling, are absent. Our results suggest a large extent of functional overlap among coronins 1, 2, and 3 in platelets, while aspects like integrin ß2 translocation are specifically or predominantly dependent on coronin 1.


Assuntos
Plaquetas/metabolismo , Cadeias beta de Integrinas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Animais , Colágeno/farmacologia , AMP Cíclico/metabolismo , Epoprostenol/farmacologia , Integrina alfa2/genética , Integrina alfa2/metabolismo , Cadeias beta de Integrinas/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Glicoproteína IIb da Membrana de Plaquetas/genética , Glicoproteína IIb da Membrana de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/genética , Ligação Proteica , Transporte Proteico , Trombina/farmacologia
16.
Platelets ; 31(7): 913-924, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31801396

RESUMO

Rapid reorganization of the actin cytoskeleton in response to receptor-mediated signaling cascades allows platelets to transition from a discoid shape to a flat spread shape upon adhesion to damaged vessel walls. Coronins are conserved regulators of the actin cytoskeleton turnover but they also participate in signaling events. To gain a better picture of their functions in platelets we have undertaken a biochemical and immunocytochemical investigation with a focus on Coro1. We found that class I coronins Coro1, 2 and 3 are abundant in human and mouse platelets whereas little Coro7 can be detected. Coro1 is mainly cytosolic, but a significant amount associates with membranes in an actin-independent manner and does not translocate from or to the membrane fraction upon exposure to thrombin, collagen or prostacyclin. Coro1 rapidly translocates to the Triton insoluble cytoskeleton upon platelet stimulation with thrombin or collagen. Coro1, 2 and 3 show a diffuse cytoplasmic localization with discontinuous accumulation at the cell cortex and actin nodules of human platelets, where all three coronins colocalize. Our data are consistent with a role of coronins as integrators of extracellular signals with actin remodeling and suggests a high extent of functional overlap among class I coronins in platelets.


Assuntos
4-Butirolactona/análogos & derivados , Plaquetas/metabolismo , Imuno-Histoquímica/métodos , 4-Butirolactona/metabolismo , Animais , Humanos , Camundongos
17.
J Clin Med ; 8(12)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817140

RESUMO

The clinical use of virtual reality (VR) has proven its efficacy, especially when used as an exposure technique. A prominent property of VR's utility is its equivalence with the reality it represents. In this study, we explored this equivalence in a clinical context using neuroimaging. A sample of 32 adults with specific phobias (i.e., to cockroaches, spiders, or lizards) was divided into two groups: One was exposed to phobic stimuli using VR and the other was exposed to real phobic images (RI). We used brain activations as a dependent measure, focusing specifically on brain areas usually associated with fear processing. Whole-brain analysis detected higher activations for RI in the hippocampus, occipital, and calcarine areas. A specific analysis of the amygdala and insula also detected higher activations and extensions in response to RI, but VR stimuli also activated those areas in a significant manner. These results suggest that even in those cases where RI stimuli activate all of the brain's fear-processing circuits, VR stimuli do so as well. This implies that VR can be useful as an exposure technique similar to RI and applied as more than a mere training mechanism.

18.
Food Res Int ; 126: 108650, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31732037

RESUMO

One of the main consequences of the advancement of harvest date associated to global climate change is that the phenolic maturity of grapes can be delayed in relation to their technological maturity. As a consequence, wines made from these grapes can be poor in phenolic compounds or possess an unbalanced phenolic composition, affecting their global quality. The combined post-fermentative addition of seeds and an astringency-modulator mannoprotein (MP) might be a potential strategy to solve this problem, since seeds might supply flavanols and improve wine chemical stability and the mannoprotein might modulate the changes induced in astringency by the addition of seeds and improve wine colloidal stability. The present study aimed at monitoring at different moments of winemaking and ageing the effects and side-effects of this combined strategy on the detailed flavanol, flavonol and anthocyanin compositions and on colour of wines made from Syrah grapes. Seeds were obtained from Pedro Ximénez overripe grapes. Flavanol composition and flavonol and anthocyanin compositions were determined by HPLC-MSn-MRM and HPLC-DAD-MSn analyses, respectively. Colour changes caused by these additions were studied from CIELAB parameters as well as the ability of these techniques to protect colour from bleaching agents, such as SO2. In general, the addition of seeds initially increased the levels of flavanols and anthocyanins. However, during bottle ageing a reduction in the levels of flavanols, flavonols and anthocyanins could be observed in seed treated wines, which might be related to the greater formation of flavanol aggregates associated with greater levels of flavanols. This effect was partially solved for most of the flavonoids studied with the additional MP treatment. Treated and control wines showed colour differences that were visible to human eye, although they were reduced over time. At the end of the study, treated wines showed colour parameters corresponding to younger wines than those observed in control wines. A greater resistance against SO2 bleaching was also observed in treated wines, which can be mainly associated to the greater percentages of polymeric pigments caused by seed treatment and to the improvement of the colloidal stability of SO2-resistant pigments caused by the addition of the MP.


Assuntos
Fermentação , Flavonoides/análise , Manipulação de Alimentos/métodos , Glicoproteínas de Membrana/administração & dosagem , Sementes/química , Vinho/análise , Antocianinas/análise , Cor , Frutas/química , Vitis/química
19.
J Agric Food Chem ; 67(14): 4031-4042, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30892885

RESUMO

The increase of temperature can cause a decoupling of sugar and anthocyanin accumulation in grapes, leading to wines poor in color. Different enological techniques are nowadays under study to overcome this problem. Among them, the present study has evaluated the color and pigment composition modifications caused by the addition during Syrah winemaking of either Pedro Ximénez seeds (intended to increase chemical stability) or/and two different mannoproteins (color-protective and astringency-modulator) to increase colloidal stability. Color and pigment composition modifications were assessed from CIELAB color parameters and from HPLC-DAD-MS n results before and after cold-treatment (used to force colloidal instability). The addition of both seeds and mannoproteins increased color stability against cold and, additionally, against SO2-bleaching in the case of mannoproteins. However, the initial pigment composition and color of the samples were differently affected by these additions, being clearly affected (Δ E* ab > 3) in the cases of seeds and with the astringency-modulator mannoprotein and hardly modified with the other one.


Assuntos
Aditivos Alimentares/química , Manipulação de Alimentos/métodos , Glicoproteínas de Membrana/química , Pigmentos Biológicos/química , Sementes/química , Vitis/química , Vinho/análise , Cor , Fermentação , Aditivos Alimentares/metabolismo , Glicoproteínas de Membrana/metabolismo , Pigmentos Biológicos/metabolismo , Saccharomyces cerevisiae/metabolismo , Vitis/metabolismo , Vitis/microbiologia , Vinho/microbiologia
20.
Cells ; 8(2)2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30754723

RESUMO

Typical Rho GTPases, such as Rac1, Cdc42, and RhoA, act as molecular switches regulating various aspects of platelet cytoskeleton reorganization. The loss of these enzymes results in reduced platelet functionality. Atypical Rho GTPases of the RhoBTB subfamily are characterized by divergent domain architecture. One family member, RhoBTB3, is expressed in platelets, but its function is unclear. In the present study we examined the role of RhoBTB3 in platelet function using a knockout mouse model. We found the platelet count, size, numbers of both alpha and dense granules, and surface receptor profile in these mice were comparable to wild-type mice. Deletion of Rhobtb3 had no effect on aggregation and dense granule secretion in response to a range of agonists including thrombin, collagen, and adenosine diphosphate (ADP). By contrast, alpha-granule secretion increased in mice lacking RhoBTB3 in response to thrombin, collagen related peptide (CRP) and U46619/ADP. Integrin activation and spreading on fibrinogen and collagen under static conditions were also unimpaired; however, we observed reduced platelet accrual on collagen under flow conditions. These defects did not translate into alterations in tail bleeding time. We conclude that genetic deletion of Rhobtb3 leads to subtle alterations in alpha-granule secretion and adhesion to collagen without significant effects on hemostasis in vivo.


Assuntos
Plaquetas/metabolismo , Colágeno/farmacologia , Grânulos Citoplasmáticos/metabolismo , Adesividade Plaquetária , Reologia , Proteínas rho de Ligação ao GTP/deficiência , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/ultraestrutura , Linhagem Celular , Grânulos Citoplasmáticos/efeitos dos fármacos , Humanos , Megacariócitos/efeitos dos fármacos , Megacariócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Adesividade Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo
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