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We have investigated the structural, bonding, and electronic properties of both ferroelectric (FE) and paraelectric (PE) phases of the hexagonal LuMnO3 compound using calculations based on density functional theory. The structural properties have been determined by employing the generalized gradient approximation with Perdew-Burke-Ernzerhof and Wu-Cohen parameterization. The bonding and electronic properties have been treated by recently developed modified Becke-Johnson exchange potential, which succeeded to open a band gap for both PE and FE phases, in agreement with experimental predictions. The Bader's topological analysis of electronic density showed that the character of the Lu-O axial bonds changes when the crystal exhibits the PE → FE structural transition. This fact is in agreement with experimental findings. The covalent character of the Lu-O bond significantly increases due to orbital hybridization between the Lu 5dz(2) and O 2pz-states. This bonding mechanism causes the ferroelectricity in the hexagonal LuMnO3 compound.

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BACKGROUND AND OBJECTIVES: Despite a confirmed association between obstructive sleep apnea (OSA) and stroke, the pathogenesis of OSA in stroke has not been hitherto clarified. The aim of this study was to evaluate the relationship between respiratory abnormalities and atherogenic pro-inflammatory markers, interleukin-1beta (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in acute ischemic stroke patients. METHODS: Nocturnal polygraphy was performed in 50 consecutive patients with acute ischemic stroke in the first week after the event. Levels of inflammatory markers (IL-6, IL-1ß and TNF-α) were determined from morning blood samples and comparatively analyzed between cases with and without severe OSA and with age-matched controls. RESULTS: All patients with acute ischemic stroke, 31 men, mean age (64.3 ± 7.7 years), had apnea-hypopnea index (AHI) > 5 and 35 (70%) had severe OSA (AHI ≥ 30). Hypertension was more frequent in patients with severe OSA (85.7%) when compared to controls (40.0%) (P = 0.002). Stroke outcome, assessed by the Barthel index, tended to be more severe (P = 0.06) in cases with severe OSA. Patients with mild/moderate OSA and with severe OSA showed higher levels of IL-6 when compared to controls (P = 0.01 and P = 0.000, respectively). Among cases with acute stroke and severe OSA, IL-6 levels were correlated with lower oxyhemoglobin desaturation (r=-0.30; P = 0.001) and with the desaturation index (r = 0.15; P = 0.02). CONCLUSIONS: IL-6, an atherogenic marker, shows a commensurate increase in stroke patients with OSA. It is correlated with oxyhemoglobin desaturation and with desaturation index and may be a surrogate measure to evaluate continuous positive airway pressure therapy.

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BACKGROUND AND PURPOSE: the objective was to evaluate the presence of Restless Legs Syndrome (RLS) in acute stroke, its association with sleep disturbances and clinical outcome during long-term follow-up. METHODS: this was a longitudinal study (N = 96, 59 men, mean age 64.0 ± 8.9) of cases with acute ischaemic stroke. Patients were asked about the occurrence of RLS symptoms before the cerebrovascular event. RLS was diagnosed using the criteria established by the International RLS Study Group. Stroke outcome was estimated by the Barthel Index and the modified Rankin Scale. Daytime somnolence (Epworth Sleepiness Scale -ESS > 10), poor sleep quality (Pittsburgh Sleep Quality Index -PSQI > 5) and risk of obstructive sleep apnea (OSA) (Berlin questionnaire) were evaluated. RESULTS: twelve patients (12.5%) met the diagnostic criteria for RLS. All cases had symptoms of RLS before stroke. However, none of the cases had a previous medical diagnosis of RLS or were on use of specific medication. In only one case, a family history of RLS was found. In all patients, RLS symptoms started after the age of 40 (mean age 64 ± 6.7). Daytime sleepiness (44.8%) and poor quality sleep (62.8%) were present. Patients with RLS (12.5%) presented greater neck circumference (P = 0.04) and worse sleep quality (P = 0.007). Risk of OSA (56.2%) was associated with hypertension [OR = 0.12; CI=0.03-0.42]. Stroke outcome was significantly worse at three and 12 months (ancova, P < 0.005) in patients with RLS, remaining after adjustment for diabetes and body mass index (P < 0.05). CONCLUSIONS: patients with acute stroke and RLS have worse clinical outcome, at three and 12 months of follow-up.

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AIMS: Several studies have demonstrated worse perception of quality of life (QoL) among patients with type 2 diabetes mellitus (T2DM). The purpose of our study was to assess QoL in a clinical sample of patients with T2DM and its association with depressive symptoms and glycemic control. METHODS: One hundred outpatients from a sequential sample underwent clinical and psychiatric evaluation. The Problem Areas of Diabetes scale (PAID) and the Beck Depression Inventory (BDI) were used to assess, respectively, QoL and the presence of overall psychopathology. The levels of glycated hemoglobin (HbA1c) were used as the main parameter of glycemic control. RESULTS: The perception degree of the QoL related with diabetes was associated with the severity of depressive symptoms (r=0.503; p<0.001), but not with HbA1c levels (p=0.117). However, the severity of general psychopathology, evaluated through the BDI scores, predicted the metabolic control, measured by HbA1c levels, among the patients in our sample (r=0.233; p=0.019). CONCLUSIONS: In our study, PAID was a valuable tool for the evaluation of QoL in T2DM and the screening of depressive symptoms. However, no correlation observed between PAID scores and HbA1c levels. Self-perception evaluation of T2DM patient can help to identify susceptible subjects to current depression.

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Cardiovascular disease is a major killer in women yet is frequently considered a male-dominated disease. The risk of cardiovascular disease in women is frequently underestimated and there is also considerable evidence of a treatment bias against women. Women are generally underrepresented in cardiovascular clinical trials yet there is evidence of gender-specific differences in the responses to pharmacotherapy. The Sibutramine Cardiovascular Outcomes (SCOUT) trial has been designed to determine whether weight management with sibutramine together with a diet- and exercise-based lifestyle intervention can prevent cardiovascular morbidity and mortality in high-risk overweight and obese patients. The SCOUT population includes a large number of older women, at high risk for cardiovascular disease. Data from the trial's lead-in phase indicate that treatment with sibutramine and lifestyle management for 6 weeks result in clinically important weight loss and reduction in waist circumference. Despite an initial lower body weight, older women with cardiovascular disease and diabetes mellitus appear to lose as much weight as men. In the overall SCOUT population, treatment with sibutramine is associated with small median decreases in systolic and diastolic blood pressure and small median increases in pulse rate. The side-effect profile of sibutramine in this older, 'at-risk' population was similar to that previously observed in younger patients.

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OBJECTIVE: There is growing evidence suggesting that obese patients may be more prone to develop certain psychiatric diseases, especially mood disorders. However, no studies have already determined which indicator of fat distribution best explains these comorbidities. The aim of this study is to investigate which anthropometric indicator of overweight (i.e. body mass index [BMI], waist circumference [WC] or waist/hip ratio [WHR]) best correlates with the presence of current mood disorders and the severity of depressive symptoms in obese women. METHODS: Two hundred seventeen (217) obese women (BMI> or =30 kg/m2) between 18 and 75 years old were selected to participate in the study. All participants had anthropometrical data registered. The diagnosis of current mood disorders was assessed according to the Portuguese version of the Structured Clinical Interview for DSM-IV [SCID]. The severity of depressive symptoms was assessed using the Beck Depression Inventory (BDI). RESULTS: A statistically significant association was found between BDI scores and BMI (r=0.16; p=0.018) and WC (r=0.20; p=0.004), but not WHR (r=0.10; p=0.15) or any socio-demographic variable. An increased prevalence of mood disorders was observed in the fourth quartile of WC, but not BMI or WHR, in comparison with the first and the second ones (p<0.05). DISCUSSION: In conclusion, obesity, per se, seems to be an independent variable associated with the severity of depressive symptoms and the prevalence of current mood disorders in obese women. Waist circumference, and not BMI or WHR, seems to be the anthropometric indicator of overweight and fat distribution that best explains these findings.

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The objective of the present study was to establish the frequency of psychiatric comorbidity in a sample of diabetic patients with symmetric distal polyneuropathy (SDPN). Sixty-five patients with type 2 diabetes mellitus were selected consecutively to participate in the study at Instituto Estadual de Diabetes e Endocrinologia. All patients were submitted to a complete clinical and psychiatric evaluation, including the Portuguese version of the structured clinical interview for DSM-IV, the Beck Depression Inventory, the Neuropathy Symptom Score, and Neuropathy Disability Score. SDPN was identified in 22 subjects (33.8%). Patients with and without SDPN did not differ significantly regarding sociodemographic characteristics. However, a trend toward a worse glycemic control was found in patients with SDPN in comparison to patients without SDPN (HbA1c = 8.43 +/- 1.97 vs 7.48 +/- 1.95; P = 0.08). Patients with SDPN exhibited axis I psychiatric disorders significantly more often than those without SDPN (especially anxiety disorders, in general (81.8 vs 60.0%; P = 0.01), and major depression--current episode, in particular (18.2 vs 7.7%; P = 0.04)). The severity of the depressive symptoms correlated positively with the severity of SDPN symptoms (r = 0.38; P = 0.006), but not with the severity of SDPN signs (r = 0.07; P = 0.56). In conclusion, the presence of SDPN seems to be associated with a trend toward glycemic control. The diagnosis of SDPN in diabetic subjects seems also to be associated with relevant psychiatric comorbidity, including anxiety and current mood disorders.

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The objective of the present study was to establish the frequency of psychiatric comorbidity in a sample of diabetic patients with symmetric distal polyneuropathy (SDPN). Sixty-five patients with type 2 diabetes mellitus were selected consecutively to participate in the study at Instituto Estadual de Diabetes e Endocrinologia. All patients were submitted to a complete clinical and psychiatric evaluation, including the Portuguese version of the structured clinical interview for DSM-IV, the Beck Depression Inventory, the Neuropathy Symptom Score, and Neuropathy Disability Score. SDPN was identified in 22 subjects (33.8 percent). Patients with and without SDPN did not differ significantly regarding sociodemographic characteristics. However, a trend toward a worse glycemic control was found in patients with SDPN in comparison to patients without SDPN (HbA1c = 8.43 ± 1.97 vs 7.48 ± 1.95; P = 0.08). Patients with SDPN exhibited axis I psychiatric disorders significantly more often than those without SDPN (especially anxiety disorders, in general (81.8 vs 60.0 percent; P = 0.01), and major depression - current episode, in particular (18.2 vs 7.7 percent; P = 0.04)). The severity of the depressive symptoms correlated positively with the severity of SDPN symptoms (r = 0.38; P = 0.006), but not with the severity of SDPN signs (r = 0.07; P = 0.56). In conclusion, the presence of SDPN seems to be associated with a trend toward glycemic control. The diagnosis of SDPN in diabetic subjects seems also to be associated with relevant psychiatric comorbidity, including anxiety and current mood disorders.

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The hypothalamic-pituitary-adrenal (HPA) axis seems to play an important role in obesity and Type 2 diabetes (DM). The aim of the present study was to determine the adrenal volume in obese patients with DM in comparison to obese non-diabetic patients. Eleven diabetic obese and 19 non-diabetic obese women were sequentially invited to take part in the study. Computed tomography (CT) scan of the abdomen was performed to determine adrenal volume, visceral (VF) and sc fat (SCF). Daily urinary free cortisol (UFC) was used as a measure of integrated cortisol production. In the diabetic patients, hemoglobin A1c was measured as an index of metabolic control. Compared to nondiabetic controls, patients with diabetes had a significantly higher total adrenal volume (4.29+/-1.50 vs 2.95+/-1.64; p=0.03). A highly significant correlation was detected between VF and VF/SCF ratio and total adrenal volume in the whole group (r=0.36, p=0.04 and r=0.48, p=0.008, respectively). This study, therefore, suggests an association between abdominal obesity, enlarged adrenals and Type 2 diabetes. These findings support the hypothesis that an increased activity of the HPA axis in obese subjects may be involved in the pathogenesis of Type 2 diabetes.

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A importância do estudo das relaçöes entre o cérebro e o sistema endócrino e o seu impacto sobre o comportamento é um dos objetivos principais da nova disciplina chamada psiconeuroendocrinologia. Dentre os vários hormônios estudados, aqueles provenientes do eixo tireoidiano têm recebido uma atençäo especial. Os autores apresentam uma revisäo da literatura referente aos aspectos psiquiátricos dos transtornos tireoidianos e apresentam cinco casos de hipertireoidismo (Doença de Basedow-Graves) que cursaram com transtorno mental orgânico. Dois destes casos apresentaram-se como "delirium" e os outros três foram diagnosticados como síndrome orgânica do humor (maníaco). A evoluçäo e a conduta terapêutica dos casos säo discutidas de acordo com literatura revista.

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A importancia do estudo das relacoes entre o cerebro e o sistema endocrino e o seu impacto sobre o comportamento e um dos objetivos principais da nova disciplina chamada psiconeuroendocrinologia. Dentre os varios hormonios estudados, aqueles provenientes do eixo tireoidiano tem recebido uma atencao especial. Os autores apresentam uma revisao da literatura referente aos aspectos psiquiatricos dos transtornos tireoidianos e apresentam cinco casos de hipertireoidismo (Doenca de Basedow-Graves) que cursaram com transtorno mental organico. Dois destes casos apresentaram-se como 'delirium'e os outros tres foram diagnosticados como sindrome organico do humor (maniaco). A evolucao e a conduta terapeutica dos casos sao discutidas de acordo com literatura revista.

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