966 resultados para adrenergic responsiveness


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One facet of self-transcendence is creative self-forgetfulness (CSF; tendency to be attentionally absorbed in mindaltering experiences). Proneness to mind-altering attentional absorption and other aspects of self-transcendence were previously related to vaginal intercourse frequency, sexual arousability, and female coital orgasm. Given that sexual responsiveness is enhanced by focused attention, itwas testedwhether CSF correlates with sexual responsiveness, and if maladaptive defenses, openness to experience, and testosterone explain the hypothesized relationships. One hundred thirty-nine Portuguese (98 women) provided saliva samples for testosterone determination by luminescence immunoassays before and after a romantic movie scene and reported how intensely they felt sexual desire and arousal during the movie. CSF was measured by the Temperament and Character Inventory– Revised, maladaptive defenses by the immature defenses subscale of the Defense Style Questionnaire (DSQ-40), male and female past month desire by the desire dimensions of the International Index of Erectile Function (IIEF), and Female Sexual Function Index (FSFI). Female desire and arousal during themoviewere independently predicted by CSF, openness to experience and testosterone, but not by immature defenses. Female past month desire was independently predicted by CSF, testosterone, and less immature defenses. Possible psychobiological processes linking self-transcendence and sexual responsiveness are discussed.

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Abstract: Scorpion stings are currently the leading cause of venom-related injury to humans in Brazil and are a significant public health problem globally. Only scorpions of the Tityus genus are of medical importance in Brazil, and Tityus serrulatus is responsible for the most serious envenomations and deaths. The toxic effects of scorpion envenomation are due to a massive release of sympathetic and parasympathetic neurotransmitters; the severity is related to cardiac and hemodynamic changes, with cardiogenic shock and pulmonary edema contributing to the main causes of death. The pathophysiology of cardiac involvement has been discussed for decades and has been attributed to adrenergic discharge and a possible toxic effect of venom on the myocardium, while acute pulmonary edema may have a cardiogenic and/or non-cardiogenic origin. Currently, the clinical data point to catecholamine excess as the cause for reversible scorpion cardiomyopathy . These data include electrocardiographic changes, profiling of cardiac enzymes and troponin I, echocardiographic data with global or regional left ventricle dysfunction, and myocardial perfusion alterations compatible with spasm in the coronary microcirculation. Furthermore, recent data on cardiac magnetic resonance imaging findings, which are similar to those observed for stress-induced cardiomyopathy, have also been linked to catecholamine excess. The efficiency of antivenom serum treatment is controversial in the literature. Our experience in Brazil is that the management of patients with systemic manifestations of scorpion stings is based on three approaches, all of which are extremely important. These include symptomatic treatment, antivenom serum, and cardiorespiratory support.

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OBJECTIVE: To evaluate the results of the laparoscopic technique in the treatment of adrenal pheochromocytoma. METHOD: Ten patients, 7 men and 3 women, between 10 and 67 years of age (mean 48) with pheochromocytoma underwent transperitoneal laparoscopic adrenalectomy and were evaluated retrospectively, based on clinical, laboratory, and pathological diagnosis. In all cases there was a solid unilateral adrenal tumor, 5 on the left side and 5 on the right side, whose greater diameter varied from 7 to 80 mm (mean 32). Nine of the 10 patients were chronically hypertensive or had already had hypertensive crises. One patient was normotensive, but presented metabolic alterations suggestive of adrenergic hyperfunction. RESULTS: No deaths occurred in this series. There were two (20%) conversions to open surgery, one due to venous bleeding and one due to the difficulty of dissection behind the vena cava in a patient presenting a partially retro-caval tumor. Surgical time in the 8 non-converted cases ranged from 70 to 215 minutes (mean 136). One patient (10%) received blood transfusion, and another (10%) presented two complications - acute renal failure and a subcutaneous infection. Both had been converted to open surgery. None of the non-converted cases was transfused or presented complications. Hospital discharge occurred between the 2nd and 11th post-operative day (mean 3). The pathological exam of the surgical specimens confirmed the diagnoses of pheochromocytoma in all 10 cases, one of them associated with an aldosterone-producing cortical tumor. CONCLUSIONS: Laparoscopic adrenalectomy for selected patients presenting pheochromocytoma is feasible and provides good results.

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Introduction: Endometriosis Health Profile Questionnaire-30 is currently the most used questionnaire for quality of life measurement in women with endometriosis. The aim of this study is to evaluate the psychometric properties and to validate the Portuguese Endometriosis Health Profile Questionnaire-30 version. MATERIAL AND METHODS A sequential sample of 152 patients with endometriosis, followed in a Portugal reference center, were asked to complete a questionnaire on social and demographic features, the Portuguese version of the Endometriosis Health Profile Questionnaire-30 and of the Short Form Health Survey 36 Item â version 2. Appropriate statistical analysis was performed using descriptive statistics, factor analysis, internal consistency, item-total correlation and convergent validity. RESULTS Factorial analysis confirmed the validity of the five-dimension structure of the Endometriosis Health Profile Questionnaire-30 core questionnaire, which explained 83.2% of the total variance. All item-total correlations presented acceptable results and high internal consistency, with Cronbach's alpha ranging between 0.876 and 0.981 for the core questionnaire and between 0.863 and 0.951 for the modular questionnaire. Significant negative associations between similar scales of Endometriosis Health Profile Questionnaire-30 and Short Form Health Survey 36 Item â version 2 were demonstrated. Data completeness achieved was high for all dimensions. The emotional well-being scale in the core questionnaire and the infertility scale in the modular section had the highest median scores, and therefore the most negative impact on the quality of life of participating women. DISCUSSION The test-retest reliability and responsiveness of the questionnaire should be evaluated in future studies. CONCLUSION The present study demonstrates that the Portuguese version of the Endometriosis Health Profile Questionnaire-30 is a valid, reliable and acceptable tool for evaluating the health-related quality of life of Portuguese women with endometriosis.

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Tese de Doutoramento em Ciências da Saúde

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Background: The activation of the beta-adrenergic system promotes G protein stimulation that, via cyclic adenosine monophosphate (cAMP), alters the structure of protein kinase A (PKA) and leads to phospholamban (PLB) phosphorylation. This protein participates in the system that controls intracellular calcium in muscle cells, and it is the primary regulator of sarcoplasmic reticulum calcium pump activity. In obesity, the beta-adrenergic system is activated by the influence of increased leptin, therefore, resulting in higher myocardial phospholamban phosphorylation via cAMP-PKA. Objective: To investigate the involvement of proteins which regulate the degree of PLB phosphorylation due to beta-adrenergic activation in obesity. In the present study, we hypothesized that there is an imbalance between phospholamban phosphorylation and dephosphorylation, with prevalence of protein phosphorylation. Methods: Male Wistar rats were randomly distributed into two groups: control (n = 14), fed with normocaloric diet; and obese (n = 13), fed with a cycle of four unsaturated high-fat diets. Obesity was determined by the adiposity index, and protein expressions of phosphatase 1 (PP-1), PKA, PLB, phosphorylated phospholamban at serine16 (PPLB-Ser16) were assessed by Western blot. Results: Obesity caused glucose intolerance, hyperinsulinemia, hypertriglyceridemia, hyperleptinemia and did not alter the protein expression of PKA, PP-1, PLB, PPLB-Ser16. Conclusion: Obesity does not promote an imbalance between myocardial PLB phosphorylation and dephosphorylation via beta-adrenergic system.

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Background: In pathological situations, such as acute myocardial infarction, disorders of motility of the proximal gut can trigger symptoms like nausea and vomiting. Acute myocardial infarction delays gastric emptying (GE) of liquid in rats. Objective: Investigate the involvement of the vagus nerve, α 1-adrenoceptors, central nervous system GABAB receptors and also participation of paraventricular nucleus (PVN) of the hypothalamus in GE and gastric compliance (GC) in infarcted rats. Methods: Wistar rats, N = 8-15 in each group, were divided as INF group and sham (SH) group and subdivided. The infarction was performed through ligation of the left anterior descending coronary artery. GC was estimated with pressure-volume curves. Vagotomy was performed by sectioning the dorsal and ventral branches. To verify the action of GABAB receptors, baclofen was injected via icv (intracerebroventricular). Intravenous prazosin was used to produce chemical sympathectomy. The lesion in the PVN of the hypothalamus was performed using a 1mA/10s electrical current and GE was determined by measuring the percentage of gastric retention (% GR) of a saline meal. Results: No significant differences were observed regarding GC between groups; vagotomy significantly reduced % GR in INF group; icv treatment with baclofen significantly reduced %GR. GABAB receptors were not conclusively involved in delaying GE; intravenous treatment with prazosin significantly reduced GR% in INF group. PVN lesion abolished the effect of myocardial infarction on GE. Conclusion: Gastric emptying of liquids induced through acute myocardial infarction in rats showed the involvement of the vagus nerve, alpha1- adrenergic receptors and PVN.

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Background:Chemotherapy with anthracyclines and trastuzumab can cause cardiotoxicity. Alteration of cardiac adrenergic function assessed by metaiodobenzylguanidine labeled with iodine-123 (123I-mIBG) seems to precede the drop in left ventricular ejection fraction.Objective:To evaluate and to compare the presence of cardiovascular abnormalities among patients with breast cancer undergoing chemotherapy with anthracyclines and trastuzumab, and only with anthracycline.Methods:Patients with breast cancer were analyzed clinical, laboratory, electrocardiographic and echocardiographic and cardiac sympathetic activity. In scintigraphic images, the ratio of 123I-mIBG uptake between the heart and mediastinum, and the washout rate were calculated. The variables were compared between patients who received anthracyclines and trastuzumab (Group 1) and only anthracyclines (Group 2).Results:Twenty patients, with mean age 57 ± 14 years, were studied. The mean left ventricular ejection fraction by echocardiography was 67.8 ± 4.0%. Mean washout rate was 28.39 ± 9.23% and the ratio of 123I-mIBG uptake between the heart and mediastinum was 2.07 ± 0.28. Of the patients, 82% showed an increased in washout rate, and the ratio of 123I-mIBG uptake between the heart and mediastinum decreased in 25%. Concerning the groups, the mean washout rate of Group 1 was 32.68 ± 9.30% and of Group 2 was 24.56 ± 7.72% (p = 0,06). The ratio of 123I-mIBG uptake between the heart and mediastinum was normal in all patients in Group 2, however, the Group 1, showed 50% the ratio of 123I-mIBG uptake between the heart and mediastinum ≤ 1.8 (p = 0.02).Conclusion:In women with breast cancer undergoing chemotherapy, assessment of cardiac sympathetic activity with 123I-mIBG appears to be an early marker of cardiotoxicity. The combination of chemotherapy showed higher risk of cardiac adrenergic hyperactivity.

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Abstract Background: Diet-induced obesity is frequently used to demonstrate cardiac dysfunction. However, some rats, like humans, are susceptible to developing an obesity phenotype, whereas others are resistant to that. Objective: To evaluate the association between obesity resistance and cardiac function, and the impact of obesity resistance on calcium handling. Methods: Thirty-day-old male Wistar rats were distributed into two groups, each with 54 animals: control (C; standard diet) and obese (four palatable high-fat diets) for 15 weeks. After the experimental protocol, rats consuming the high-fat diets were classified according to the adiposity index and subdivided into obesity-prone (OP) and obesity-resistant (OR). Nutritional profile, comorbidities, and cardiac remodeling were evaluated. Cardiac function was assessed by papillary muscle evaluation at baseline and after inotropic maneuvers. Results: The high-fat diets promoted increase in body fat and adiposity index in OP rats compared with C and OR rats. Glucose, lipid, and blood pressure profiles remained unchanged in OR rats. In addition, the total heart weight and the weight of the left and right ventricles in OR rats were lower than those in OP rats, but similar to those in C rats. Baseline cardiac muscle data were similar in all rats, but myocardial responsiveness to a post-rest contraction stimulus was compromised in OP and OR rats compared with C rats. Conclusion: Obesity resistance promoted specific changes in the contraction phase without changes in the relaxation phase. This mild abnormality may be related to intracellular Ca2+ handling.

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Abstract Background: More than 50% of the patients with heart failure have normal ejection fraction (HFNEF). Iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy and cardiopulmonary exercise test (CPET) are prognostic markers in HFNEF. Nebivolol is a beta-blocker with vasodilating properties. Objectives: To evaluate the impact of nebivolol therapy on CPET and123I-MIBG scintigraphic parameters in patients with HFNEF. Methods: Twenty-five patients underwent 123I-MIBG scintigraphy to determine the washout rate and early and late heart-to-mediastinum ratios. During the CPET, we analyzed the systolic blood pressure (SBP) response, heart rate (HR) during effort and recovery (HRR), and oxygen uptake (VO2). After the initial evaluation, we divided our cohort into control and intervention groups. We then started nebivolol and repeated the tests after 3 months. Results: After treatment, the intervention group showed improvement in rest SBP (149 mmHg [143.5-171 mmHg] versus 135 mmHg [125-151 mmHg, p = 0.016]), rest HR (78 bpm [65.5-84 bpm] versus 64.5 bpm [57.5-75.5 bpm, p = 0.028]), peak SBP (235 mmHg [216.5-249 mmHg] versus 198 mmHg [191-220.5 mmHg], p = 0.001), peak HR (124.5 bpm [115-142 bpm] versus 115 bpm [103.7-124 bpm], p= 0.043), HRR on the 1st minute (6.5 bpm [4.75-12.75 bpm] versus 14.5 bpm [6.7-22 bpm], p = 0.025) and HRR on the 2nd minute (15.5 bpm [13-21.75 bpm] versus 23.5 bpm [16-31.7 bpm], p = 0.005), but no change in peak VO2 and 123I-MIBG scintigraphic parameters. Conclusion: Despite a better control in SBP, HR during rest and exercise, and improvement in HRR, nebivolol failed to show a positive effect on peak VO2 and 123I-MIBG scintigraphic parameters. The lack of effect on adrenergic activity may be the cause of the lack of effect on functional capacity.

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It is well-known that couples that look jointly for jobs in the same centralized labor market may cause instabilities. We demonstrate that for a natural preference domain for couples, namely the domain of responsive preferences, the existence of stable matchings can easily be established. However, a small deviation from responsiveness in one couple's preference relation that models the wish of a couple to be closer together may already cause instability. This demonstrates that the nonexistence of stable matchings in couples markets is not a singular theoretical irregularity. Our nonexistence result persists even when a weaker stability notion is used that excludes myopic blocking. Moreover, we show that even if preferences are responsive there are problems that do not arise for singles markets. Even though for couples markets with responsive preferences the set of stable matchings is nonempty, the lattice structure that this set has for singles markets does not carry over. Furthermore we demonstrate that the new algorithm adopted by the National Resident Matching Program to fill positions for physicians in the United States may cycle, while in fact a stable matchings does exist, and be prone to strategic manipulation if the members of a couple pretend to be single.

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The production of hyperglycemia during the acute phase of scorpion poisoning produced by T. bahiensis in dogs is confirmed now. The highest degree on average, was reached 10 minutes after the injection of venom. In our hands, the previous bilateral adrenalectomy did not avoid the hyperglycemia. The average of the blood sugar level has been similar to that observed in dogs with adrenal glands, the highest blood sugar level was also registered after 10 minutes. The hyperglycemia obtained in adrenolectomized dogs is, probably, due to the liberation of Sympatin (Nor-adrenalin and adrenalin) as a consequence of the central excitation by the poison on the hepatic nerves and other ganglionar terminations of the Sympathetic Nervous System. Our present researches suggest that the venom has adrenergic action besides the central action.

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In the present paper we studied the mechanism of the hyperglycemia and hypertension evoked by the intravenous injection of scorpion venom (Tityus bahiensis) in the dog. We used 34 dogs, of both sex, weighing between 4.3 to 22 kg. These animals were divided in 3 groups and the following experiments were performed: in the first group (8 dogs) the animals were adrenalectomized after the intravenous injection of chlorpromazine; in the second group (16 dogs) the animals were injected with ganglionic blocking drugs (9.295 Ciba and hexamethonium); in the third group (10 dogs) the naimals were injected with dibenamine, and in 3 of them the adrenal glands were removed. The dogs of each group were injected intravenously with aqueous extract of 2 telsons of scorpion/kg; the average weight of each telson was 6,5 mg. The following results were obtained: 1) The hyperglycemia evoked by scorpion venom, in adrenalectomized dogs, was inhibited by chlorpromazine; 2) Ganglionic blocking drugs (9.295 Ciba and hexamthonium) were inefective as far as the hyperglycemic and pressor effects of venom are concerned; 3) In the animals treated with dibenamine, the venom produced a fall in blood pressure, both in the controle and in the adrenalectomized. The present experiments suggest that the scorpion venom has, besides the central action already described by other investigators, an adrenergic action, very similar to the adrenaline. On basis of our experiments we think that the adrenergic action is responsible, in part, by the productrion of hyperglycemia and hypertension.