888 resultados para Fear-relevance
Resumo:
Nuclear inositide signalling pathways, and particularly those regulated by PI-PLCβ1, are associated with cell proliferation and differentiation. Myelodysplastic syndromes (MDS) are a heterogeneous spectrum of chronic myeloid hemopathies with associated symptomatic cytopenias and substantial potential for evolution to acute myeloid leukemia (AML). MDS patients are currently treated with two main approaches, epigenetic (Azacitidine) and immunomodulatory (Lenalidomide: above all in cell clones bearing a deletion of the long arm of the chromosome 5 [del(5q)]). As Azacitidine and Lenalidomide alone can show adverse effects or patients can be refractory, an experimental current approach is the combination of the two drugs. Clinically, this combination therapy is promising, while its molecular effect has to be clarified. Stemming from these data, in this study the effect of an Azacitidine-Lenalidomide combination therapy was studied, in both MDS patients and hematopoietic cell lines. The specific aims of this study were to evaluate the effect of Azacitidine and Lenalidomide MDS therapy on: cell cycle regulation, hematopoietic differentiation, gene mutation and miR expression. Lenalidomide alone, via PI-PLCβ1/PKC pathway, was able to induce a selective G0/G1 arrest of the cell cycle in del(5q) cells, slowing down their rate proliferation and favouring erythropoiesis activation. In addition, although the mutation profile at baseline was not entirely capable of predicting the clinical effect of Azacitidine and Lenalidomide therapy, the presence of specific point mutations affecting three inositide genes (PI3KCD, AKT3, PLCG2) was correlated to and anticipated a negative clinical outcome. Moreover, the differential miR expression was detectable even from the 4th cycle of therapy in responder patients, as compared to non-responders. In MDS, this is the first evidence that the molecular mutation profiling of inositide genes or a specific mini-cluster of differentially expressed miRs, targeting inositide signaling molecules, can be associated with the clinical response, thus possibly predicting the effect of the therapy.
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Fear of Missing Out (FoMO) is a pervasive apprehension that others might be having rewarding experiences from which one is absent. Consequently, individuals experiencing FoMO wish to stay constantly in contact with what others are doing and engage with social networking sites for this purpose. In recent times, FoMO has received increased attention from psychological research, as a minority of users experiencing high levels of FoMO - particularly young people - might develop a problematic social networking site use, defined as the maladaptive and excessive use of social networking sites, resulting in symptoms associated with other addictions. According to the theoretical framework of the Interaction of Person-Affect-Cognition- Execution (I-PACE) model, FoMO and certain motives for use may foster problematic use in individuals who display unmet psychosocial needs. However, to date, the I-PACE model has only conceptualized the general higher-order mechanisms related to the development of problematic use. Consistently, the overall purpose of this dissertation was to deepen the understanding of the mediating role of FoMO between specific predisposing variables and problematic social networking sites use. Adopting a psychological approach, two empirical and exploratory cross-sectional studies, conceived as independent research, were conducted through path analysis.
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Lipid peroxidation is a complex mechanism that causes the degradation of lipid material of both industrial and biological significance. During processing, it is known that thermal stress produces oxidation and polymerization of oils. Additionally, biological lipids with both structural and bioactive roles are prone to peroxidation, which can have pathogenic effects including cancer and long-term degenerative disorders. To create innovative strategies to slow down the deterioration of lipids, it is crucial to improve our understanding of oxidation reactions and kinetics. To this purpose, Chapter II of this thesis focuses on the kinetic study of the oxidation reactions that take place during the thermal processing of bio-oils for industrial application. Through a new method it was possible to evaluate the kinetic parameters of oxidation of various lipid materials. This allowed us to distinguish between the different lipid materials based on their intrinsic properties. The effect of 18 antioxidants from the major families of natural and synthetic phenols were studied using the same methodology in order to acquire crucial data for enhancing the antioxidant activity of phenols based on structure-activity at high temperatures. Finally, it has been described how the antioxidant activity of α-tocopherol, revealed to be scarce in our conditions, can be improved in the presence of gamma-terpinene, through a synergistic action. Chapter III describes the synthesis and study of the antioxidant activity of polydopamine nanoparticles, in order to clarify the unclear mechanism of action of this material. Finally, in Chapter IV it was reported how the gamma-terpinene strongly inhibits the peroxidation of unsaturated lipids in heterogeneous model systems (micelles and liposomes) by forming hydroperoxyl radicals which diffuse outside the lipid nucleus, blocking the propagation of the chain radical. Furthermore, gamma-terpinene shows a very potent protective activity against ferroptosis being effective in the nanomolar range in the human neuroblastoma cell model.
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Xanthomonas citri subsp. citri (X. citri) is the causative agent of the citrus canker, a disease that affects several citrus plants in Brazil and across the world. Although many studies have demonstrated the importance of genes for infection and pathogenesis in this bacterium, there are no data related to phosphate uptake and assimilation pathways. To identify the proteins that are involved in the phosphate response, we performed a proteomic analysis of X. citri extracts after growth in three culture media with different phosphate concentrations. Using mass spectrometry and bioinformatics analysis, we showed that X. citri conserved orthologous genes from Pho regulon in Escherichia coli, including the two-component system PhoR/PhoB, ATP binding cassette (ABC transporter) Pst for phosphate uptake, and the alkaline phosphatase PhoA. Analysis performed under phosphate starvation provided evidence of the relevance of the Pst system for phosphate uptake, as well as both periplasmic binding proteins, PhoX and PstS, which were formed in high abundance. The results from this study are the first evidence of the Pho regulon activation in X. citri and bring new insights for studies related to the bacterial metabolism and physiology. Biological significance Using proteomics and bioinformatics analysis we showed for the first time that the phytopathogenic bacterium X. citri conserves a set of proteins that belong to the Pho regulon, which are induced during phosphate starvation. The most relevant in terms of conservation and up-regulation were the periplasmic-binding proteins PstS and PhoX from the ABC transporter PstSBAC for phosphate, the two-component system composed by PhoR/PhoB and the alkaline phosphatase PhoA.
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Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules.
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Long-acting reversible contraceptives (LARCs) include the copper-releasing intrauterine device (IUD), the levonorgestrel-releasing intrauterine system (LNG-IUS) and implants. Despite the high contraceptive efficacy of LARCs, their prevalence of use remains low in many countries. The objective of this study was to assess the main reasons for switching from contraceptive methods requiring daily or monthly compliance to LARC methods within a Brazilian cohort. Women of 18-50 years of age using different contraceptives and wishing to switch to a LARC method answered a questionnaire regarding their motivations for switching from their current contraceptive. Continuation rates were evaluated 1 year after method initiation. Sample size was calculated at 1040 women. Clinical performance was evaluated by life table analysis. The cutoff date for analysis was May 23, 2013. Overall, 1167 women were interviewed; however, after 1 year of use, the medical records of only 1154 women were available for review. The main personal reason for switching, as reported by the women, was fear of becoming pregnant while the main medical reasons were nausea and vomiting and unscheduled bleeding. No pregnancies occurred during LARC use, and the main reasons for discontinuation were expulsion (in the case of the IUD and LNG-IUS) and a decision to undergo surgical sterilization (in the case of the etonogestrel-releasing implant). Continuation rate was ~95.0/100 women/year for the three methods. Most women chose a LARC method for its safety and for practical reasons, and after 1 year of use, most women continued with the method.
Resumo:
The arboreal ant Odontomachus hastatus nests among roots of epiphytic bromeliads in the sandy forest at Cardoso Island (Brazil). Crepuscular and nocturnal foragers travel up to 8m to search for arthropod prey in the canopy, where silhouettes of leaves and branches potentially provide directional information. We investigated the relevance of visual cues (canopy, horizon patterns) during navigation in O. hastatus. Laboratory experiments using a captive ant colony and a round foraging arena revealed that an artificial canopy pattern above the ants and horizon visual marks are effective orientation cues for homing O. hastatus. On the other hand, foragers that were only given a tridimensional landmark (cylinder) or chemical marks were unable to home correctly. Navigation by visual cues in O. hastatus is in accordance with other diurnal arboreal ants. Nocturnal luminosity (moon, stars) is apparently sufficient to produce contrasting silhouettes from the canopy and surrounding vegetation, thus providing orientation cues. Contrary to the plain floor of the round arena, chemical cues may be important for marking bifurcated arboreal routes. This experimental demonstration of the use of visual cues by a predominantly nocturnal arboreal ant provides important information for comparative studies on the evolution of spatial orientation behavior in ants. This article is part of a Special Issue entitled: Neotropical Behaviour.
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Ant foraging on foliage can substantially affect how phytophagous insects use host plants and represents a high predation risk for caterpillars, which are important folivores. Ant-plant-herbivore interactions are especially pervasive in cerrado savanna due to continuous ant visitation to liquid food sources on foliage (extrafloral nectaries, insect honeydew). While searching for liquid rewards on plants, aggressive ants frequently attack or kill insect herbivores, decreasing their numbers. Because ants vary in diet and aggressiveness, their effect on herbivores also varies. Additionally, the differential occurrence of ant attractants (plant and insect exudates) on foliage produces variable levels of ant foraging within local floras and among localities. Here, we investigate how variation of ant communities and of traits among host plant species (presence or absence of ant attractants) can change the effect of carnivores (predatory ants) on herbivore communities (caterpillars) in a cerrado savanna landscape. We sampled caterpillars and foliage-foraging ants in four cerrado localities (70-460 km apart). We found that: (i) caterpillar infestation was negatively related with ant visitation to plants; (ii) this relationship depended on local ant abundance and species composition, and on local preference by ants for plants with liquid attractants; (iii) this was not related to local plant richness or plant size; (iv) the relationship between the presence of ant attractants and caterpillar abundance varied among sites from negative to neutral; and (v) caterpillars feeding on plants with ant attractants are more resistant to ant predation than those feeding on plants lacking attractants. Liquid food on foliage mediates host plant quality for lepidopterans by promoting generalized ant-caterpillar antagonism. Our study in cerrado shows that the negative effects of generalist predatory ants on herbivores are detectable at a community level, affecting patterns of abundance and host plant use by lepidopterans. The magnitude of ant-induced effects on caterpillar occurrence across the cerrado landscape may depend on how ants use plants locally and how they respond to liquid food on plants at different habitats. This study enhances the relevance of plant-ant and ant-herbivore interactions in cerrado and highlights the importance of a tritrophic perspective in this ant-rich environment.
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to assess the construct validity and reliability of the Pediatric Patient Classification Instrument. correlation study developed at a teaching hospital. The classification involved 227 patients, using the pediatric patient classification instrument. The construct validity was assessed through the factor analysis approach and reliability through internal consistency. the Exploratory Factor Analysis identified three constructs with 67.5% of variance explanation and, in the reliability assessment, the following Cronbach's alpha coefficients were found: 0.92 for the instrument as a whole; 0.88 for the Patient domain; 0.81 for the Family domain; 0.44 for the Therapeutic procedures domain. the instrument evidenced its construct validity and reliability, and these analyses indicate the feasibility of the instrument. The validation of the Pediatric Patient Classification Instrument still represents a challenge, due to its relevance for a closer look at pediatric nursing care and management. Further research should be considered to explore its dimensionality and content validity.
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Facial pain often persists long after any identifiable organic pathology has healed. Moreover, in a subgroup of patients with temporomandibular disorder (TMD), no treatment is effective. Knowledge of factors associated with persistent pain in TMD could help identify personalized treatment approaches. Therefore, we conducted a critical review of the literature for the period from January 2000 to December 2013 to identify factors related to TMD development and persistence. The literature findings showed that chronic TMD is marked by psychological distress (somatization and depression, affective distress, fear of pain, fear of movement, and catastrophizing) and characteristics of pain amplification (hyperalgesia and allodynia). Furthermore, these factors seem to interact in TMD development. In addition, our review demonstrates that upregulation of the serotonergic pathway, sleep problems, and gene polymorphisms influence the chronicity of TMD. We conclude that psychological distress and pain amplification contribute to chronic TMD development, and that interactions among these factors complicate pain management. These findings emphasize the importance of multidisciplinary assistance in TMD treatment.
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Oropouche virus (OROV) is a member of the Orthobunyavirus genus in the Bunyaviridae family and a prominent cause of insect-transmitted viral disease in Central and South America. Despite its clinical relevance, little is known about OROV pathogenesis. To define the host defense pathways that control OROV infection and disease, we evaluated OROV pathogenesis and immune responses in primary cells and mice that were deficient in the RIG-I-like receptor signaling pathway (MDA5, RIG-I, or MAVS), downstream regulatory transcription factors (IRF-3 or IRF-7), IFN-β, or the receptor for type I IFN signaling (IFNAR). OROV replicated to higher levels in primary fibroblasts and dendritic cells lacking MAVS signaling, the transcription factors IRF-3 and IRF-7, or IFNAR. In mice, deletion of IFNAR, MAVS, or IRF-3 and IRF-7 resulted in uncontrolled OROV replication, hypercytokinemia, extensive liver damage, and death whereas wild-type (WT) congenic animals failed to develop disease. Unexpectedly, mice with a selective deletion of IFNAR on myeloid cells (CD11c Cre(+) Ifnar(f/f) or LysM Cre(+) Ifnar(f/f)) did not sustain enhanced disease with OROV or La Crosse virus, a closely related encephalitic orthobunyavirus. In bone marrow chimera studies, recipient irradiated Ifnar(-/-) mice reconstituted with WT hematopoietic cells sustained high levels of OROV replication and liver damage, whereas WT mice reconstituted with Ifnar(-/-) bone marrow were resistant to disease. Collectively, these results establish a dominant protective role for MAVS, IRF-3 and IRF-7, and IFNAR in restricting OROV virus infection and tissue injury, and suggest that IFN signaling in non-myeloid cells contributes to the host defense against orthobunyaviruses. Oropouche virus (OROV) is an emerging arthropod-transmitted orthobunyavirus that causes episodic outbreaks of a debilitating febrile illness in humans in countries of South and Central America. The continued expansion of the range and number of its arthropod vectors increases the likelihood that OROV will spread into new regions. At present, the pathogenesis of OROV in humans or other vertebrate animals remains poorly understood. To define cellular mechanisms of control of OROV infection, we performed infection studies in a series of primary cells and mice that were deficient in key innate immune genes involved in pathogen recognition and control. Our results establish that a MAVS-dependent type I IFN signaling pathway has a dominant role in restricting OROV infection and pathogenesis in vivo.
Resumo:
Machado-Joseph disease (SCA3) is the most frequent spinocerebellar ataxia worldwide and characterized by remarkable phenotypic heterogeneity. MRI-based studies in SCA3 focused in the cerebellum and connections, but little is known about cord damage in the disease and its clinical relevance. To evaluate the spinal cord damage in SCA3 through quantitative analysis of MRI scans. A group of 48 patients with SCA3 and 48 age and gender-matched healthy controls underwent MRI on a 3T scanner. We used T1-weighted 3D images to estimate the cervical spinal cord area (CA) and eccentricity (CE) at three C2/C3 levels based on a semi-automatic image segmentation protocol. The scale for assessment and rating of ataxia (SARA) was employed to quantify disease severity. The two groups-SCA3 and controls-were significantly different regarding CA (49.5 ± 7.3 vs 67.2 ± 6.3 mm(2), p < 0.001) and CE values (0.79 ± 0.06 vs 0.75 ± 0.05, p = 0.005). In addition, CA presented a significant correlation with SARA scores in the patient group (p = 0.010). CE was not associated with SARA scores (p = 0.857). In the multiple variable regression, we found that disease duration was the only variable associated with CA (coefficient = -0.629, p = 0.025). SCA3 is characterized by cervical cord atrophy and antero-posterior flattening. In addition, the spinal cord areas did correlate with disease severity. This suggests that quantitative analyses of the spinal cord MRI might be a useful biomarker in SCA3.
Resumo:
OBJECTIVE: To verify the effectiveness of the support group in the identification of family variables linked to epilepsy. METHOD: Pre-test were applied to parents of 21 children with benign epilepsy of childhood recently diagnosed, from 5 to 15 years, who participated in the groups at HC/Unicamp. There was a presentation of an educational video, discussion and application of the post-test 1. After six months, the post-test 2 was applied. RESULTS: The beliefs were: fear of swallowing the tongue during the seizures (76.19%) and of a future mental disease (66.67%). Facing the epilepsy, fear and sadness appeared. 76.19% of the parents presented overprotection and 90.48%, expected a new seizure. In the post-test 1, the parents affirmed that the information offered had modified the beliefs. In the post-test 2, 80.95% didn't report great doubts about epilepsy and 90.48% considered their relationship with their children better. CONCLUSIONS: The demystification of beliefs supplied from the groups influenced the family positively, prevented behavior alterations and guaranteed effective care in the attendance to the child with epilepsy.
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The use of poorly water soluble molecules in pharmaceutical area has grown. Since these molecules exhibit low oral bioavailability, they are not used in intravenous administrations. Therefore, it is necessary to develop their new formulations with the aim to increase their oral bioavailabilities as to enable intravenous applications. One of the few possibilities in achieving this is a nanonization process that can produce crystals smaller than 1 μm by high pressure homogenization and without use of organic solvents. This mini-review describes technical aspects of the nanocrystal production, morphological aspects (polymorphisms), the market relevance of the nanocrystals products that are already in clinical phase or at the market, as well as, perspectives for the near future.
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In this paper we present a study of reading comprehension based on a contrastive argumentative-discursive approach. We examine the relationship between linguistic materiality and discursive processes, observing the connection between reading in a foreign language, writing production and textual memories in the mother tongue. In addition to an interest in practical language teaching and learning processes (in this case of Spanish and Portuguese), we investigate the question of politeness and the theoretical relationship between subjectivity, language, and textuality. The latter, being understood as the result of discourse regularities, is unique for each and every production, yet is also conditioned by plural discursive memories resulting from contradictory social relationships in a specific historical context (Foucault, 1986; Pêcheux, 1990). In the experiment presented here, we follow some of the procedures of the methodology applied in the European Galatea Project developed for the study of reading strategies in the inter-comprehension between Romance languages (Dabène, 1996). We use the procedure of simulation and the subjective projection of participants as well as the notion of discursive resonance in the analysis. The results, having to do with directness and indirectness in speech and the question of politeness in two typologically close languages, lead to the conclusion that the concept of politeness goes beyond a pragmatic strategy used to avoid conflicts to be approached as a marker of cultural identity constitution. The relevance of discursive awareness and its theoretical and practical consequences are then emphasized.