965 resultados para Pressor reactivity
Resumo:
The present study examined trait self-compassion and trait self-esteem in relation to positive (PA) and negative affect (NA), as well as their associations with stress reactivity in daily life. One hundred and one subjects completed questionnaires on perceived stress and affect twice a day for 14 consecutive days on smart phones. Results indicated that self-compassion and global self-esteem were positively related to PA and negatively to NA. After controlling for self-esteem, self-compassion remained significantly associated with PA and NA, whereas self-esteem was no longer associated with PA and NA after controlling for self-compassion. Furthermore, results indicated that self-compassion buffered the effect of stress on NA, whereas this was not the case for global self-esteem. Neither self-compassion nor self-esteem moderated the relation of stress on PA in separate models. The results of the present study add to the growing literature regarding beneficial relations of self-compassion and psychological well-being and further emphasize the distinction of self-compassion and global self-esteem.
Resumo:
Bipolar Disorder (BD) is a recurrent and debilitating psychological disorder characterized by a chronic dysregulation of mood with fluctuations between extremely low (e.g., depression) and extremely elevated mood states (e.g., mania), and ranks as the 6th leading cause of disability in the world. Although research has consistently shown that exercise may have antidepressant and stress-attenuating benefits in other psychiatric illnesses (e.g., depression, anxiety), these benefits have not been directly investigated for BD. The current study represents the first known investigation to examine this relationship. Single-participant designs, with crossover and interaction treatment components (i.e., A/B/A/B/A, A/C/A/C/A, A/B/A/C/A, or A/C/A/B/A) were utilized to investigate the impact of participation in a prescribed regimen of exercise (EP) versus standard behavioral activation (SBA; i.e., non-exercise activity) has on stress perception and reactivity, and mood stability in a sample of individuals with BD. Individuals completed four total weeks of treatment, and psychophysiological measures of reactivity were recorded during a laboratory stress task (i.e., backward counting task) prior to and following each two-week intervention phase. No appreciable differences were found between levels of exercise participation between treatment groups. Interestingly, symptoms of depressed mood (BDI-II scores) decreased at similar rates following 4 weeks of treatment for all participants. BDI-II decreases were found to be most correlated with elective exercise participation, although this relationship was not significant. Regarding stress reactivity, elective participation in mild to moderate intensity exercise was found to reduce an individual’s perception of stress reactivity to an acute stressor, while participation in a prescribed program of exercise was more effective in reducing physiological response to the same task. Utilizing multiple forms of behavioral activation simultaneously was found to be most effective in decreasing perception of stress reactivity, and may also result in a positive change in the use of adaptive versus maladaptive coping strategies. Participation in a 4-week program of exercise appeared to provide the most benefit, consistent with exercise habituation theories. Overall, current findings provide preliminary support for the prophylactic benefits of including a prescribed and monitored program of exercise as an adjunct treatment for individuals with BD. Larger scale research is needed to more clearly determine the impact of exercise on stress reactivity and mood episode relapse in individuals with BD.
Resumo:
Antibodies (Abs) to autoantigens and foreign antigens (Ags) mediate, respectively, various pathogenic and beneficial effects. Abs express enzyme-like nucleophiles that react covalently with electrophiles. A subpopulation of nucleophilic Abs expresses proteolytic activity, which can inactivate the Ag permanently. This thesis shows how the nucleophilicity can be exploited to inhibit harmful Abs or potentially protect against a virus. ^ Inactivation of pathogenic Abs from Hemophilia A (HA) patients by means of nucleophile-electrophile pairing was studied. Deficient factor VIII (FVIII) in HA subjects impairs blood coagulation. FVIII replacement therapy fails in 20-30% of HA patients due to production of anti-FVIII Abs. FVIII analogs containing electrophilic phosphonate group (E-FVIII and E-C2) were hypothesized to inactivate the Abs by reacting specifically and covalently with nucleophilic sites. Anti-FVIII IgGs from HA patients formed immune complexes with E-FVIII and E-C2 that remained irreversibly associated under conditions that disrupt noncovalent Ab-Ag complexes. The reaction induced irreversible loss of Ab anti-coagulant activity. E-FVIII alone displayed limited interference with coagulation. E-FVIII is a prototype reagent suitable for further development as a selective inactivator of pathogenic anti-FVIII Abs. ^ The beneficial function of Abs to human immunodeficiency virus type 1 (HIV-1) was analyzed. HIV-1 eludes the immune system by rapidly changing its coat protein structure. IgAs from noninfected subjects hydrolyzed gp120 and neutralized HIV-1 with modest potency by recognizing the gp120 421-433 epitope, a conserved B cell superantigenic region that is also essential for HIV-1 attachment to host cell CD4 receptors. An adaptive immune response to superantigens is generally prohibited due to their ability to downregulate B cells. IgAs from subjects with prolonged HIV-1 infection displayed improved catalytic hydrolysis of gp120 and exceptionally potent and broad neutralization of diverse CCR5-dependent primary HIV isolates attributable to recognition of the 421-433 epitope. This indicates that slow immunological bypass of the superantigenic character of gp120 is possible, opening the path to effective HIV vaccination. ^ My research reveals a novel route to inactivate pathogenic nucleophilic Abs using electrophilic antigens. Conversely, naturally occurring nucleophilic Abs may help impede HIV infection, and the Abs could be developed for passive immunotherapy of HIV infected subjects. ^
Resumo:
The study of cross-reactivity in allergy is key to both understanding. the allergic response of many patients and providing them with a rational treatment In the present study, protein microarrays and a co-sensitization graph approach were used in conjunction with an allergen microarray immunoassay. This enabled us to include a wide number of proteins and a large number of patients, and to study sensitization profiles among members of the LTP family. Fourteen LTPs from the most frequent plant food-induced allergies in the geographical area studied were printed into a microarray specifically designed for this research. 212 patients with fruit allergy and 117 food-tolerant pollen allergic subjects were recruited from seven regions of Spain with different pollen profiles, and their sera were tested with allergen microarray. This approach has proven itself to be a good tool to study cross-reactivity between members of LTP family, and could become a useful strategy to analyze other families of allergens.
Resumo:
Cross-reactivity of plant foods is an important phenomenon in allergy, with geographical variations with respect to the number and prevalence of the allergens involved in this process, whose complexity requires detailed studies. We have addressed the role of thaumatin-like proteins (TLPs) in cross-reactivity between fruit and pollen allergies. A representative panel of 16 purified TLPs was printed onto an allergen microarray. The proteins selected belonged to the sources most frequently associated with peach allergy in representative regions of Spain. Sera from two groups of well characterized patients, one with allergy to Rosaceae fruit (FAG) and another against pollens but tolerant to food-plant allergens (PAG), were obtained from seven geographical areas with different environmental pollen profiles. Cross-reactivity between members of this family was demonstrated by inhibition assays. Only 6 out of 16 purified TLPs showed noticeable allergenic activity in the studied populations. Pru p 2.0201, the peach TLP (41%), chestnut TLP (24%) and plane pollen TLP (22%) proved to be allergens of probable relevance to fruit allergy, being mainly associated with pollen sensitization, and strongly linked to specific geographical areas such as Barcelona, Bilbao, the Canary Islands and Madrid. The patients exhibited mayor que50% positive response to Pru p 2.0201 and to chestnut TLP in these specific areas. Therefore, their recognition patterns were associated with the geographical area, suggesting a role for pollen in the sensitization of these allergens. Finally, the co-sensitizations of patients considering pairs of TLP allergens were analyzed by using the co-sensitization graph associated with an allergen microarray immunoassay. Our data indicate that TLPs are significant allergens in plant food allergy and should be considered when diagnosing and treating pollen-food allergy.