136 research outputs found
Erectile Dysfunction and Hypertension: Impact on Cardiovascular Risk and Treatment
Erectile dysfunction (ED) is a common complaint in hypertensive men and can represent a systemic vascular disease, an adverse effect of antihypertensive medication or a frequent concern that may impair drug compliance. ED has been considered an early marker of cardiovascular disease. The connection between both conditions seems to be located in the endothelium, which may become unable to generate the necessary dilatation in penile vascular bed in response to sexual excitement, producing persistent impairment in erection. On the other hand, the real influence of antihypertensive drugs in erectile function still deserves discussion. Therefore, regardless of ED mechanism in hypertension, early diagnosis and correct approach of sexual life represent an important step of cardiovascular evaluation which certainly contributes for a better choice of hypertension treatment, preventing some complications and restoring the quality of life
Risk Factors Related to Low Ankle-Brachial Index Measured by Traditional and Modified Definition in Hypertensive Elderly Patients
Peripheral arterial disease (PAD) increases with age and ankle-brachial index (ABI) ≤ 0.9 is a noninvasive marker of PAD. The purpose of this study was to identify risk factors related to a low ABI in the elderly using two different methods of ABI calculation (traditional and modified definition using lower instead of higher ankle pressure). A cross-sectional study was carried out with 65 hypertensive patients aged 65 years or older. PAD was present in 18% of individuals by current ABI definition and in 32% by modified method. Diabetes, cardiovascular diseases, metabolic syndrome, higher levels of systolic blood pressure and pulse pressure, elevated risk by Framingham Risk Score (FRS), and a higher number of total and antihypertensive drugs in use were associated with low ABI by both definitions. Smoking and LDL-cholesterol were associated with low ABI only by the modified definition. Low ABI by the modified definition detected 9 new cases of PAD but cardiovascular risk had not been considered high in 3 patients when calculated by FRS. In conclusion, given that a simple modification of ABI calculation would be able to identify more patients at high risk, it should be considered for cardiovascular risk prediction in all elderly hypertensive outpatients
Ambulatory Arterial Stiffness Index Is Higher in Hypertensive Patients with Chronic Kidney Disease
Ambulatory arterial stiffness index (AASI) is a parameter obtained from ambulatory blood pressure monitoring (ABPM) that correlates with clinical endpoints. The aim of this study was to compare AASI in nondiabetic hypertensive patients with and without chronic kidney disease (CKD). Subjects with systemic arterial hypertension (SAH, n = 30) with normal renal function, aged 40 to 75 years, were compared to hypertensive patients with CKD (n = 30) presenting estimated glomerular filtration rate (eGFR) <60 mL/min by MDRD formula. ABPM was carried out in all patients. In CKD group, eGFR was 35.3 ± 2.8 ml/min. The mean 24-hour systolic and diastolic blood pressure (BP) was similar in both groups. AASI was significantly higher in CKD group (0.45 ± 0.03 versus 0.37 ± 0.02, P < 0.05), positively correlated to age (r = 0.38, P < 0.01) and pulse pressure (r = 0.43, P < 0.01) and negatively correlated to nocturnal BP fall (r = -0.28, P = 0.03). These findings indicate the presence of stiffer vessels in CKD hypertensive patients
Erectile Dysfunction and Hypertension: Impact on Cardiovascular Risk and Treatment
Erectile dysfunction (ED) is a common complaint in hypertensive men and can represent a systemic vascular disease, an adverse effect of antihypertensive medication or a frequent concern that may impair drug compliance. ED has been considered an early marker of cardiovascular disease. The connection between both conditions seems to be located in the endothelium, which may become unable to generate the necessary dilatation in penile vascular bed in response to sexual excitement, producing persistent impairment in erection. On the other hand, the real influence of antihypertensive drugs in erectile function still deserves discussion. Therefore, regardless of ED mechanism in hypertension, early diagnosis and correct approach of sexual life represent an important step of cardiovascular evaluation which certainly contributes for a better choice of hypertension treatment, preventing some complications and restoring the quality of life
Vascular Dysfunction as Target Organ Damage in Animal Models of Hypertension
Endothelial dysfunction is one of the main characteristics of chronic hypertension and it is characterized by impaired nitric oxide (NO) bioactivity determined by increased levels of reactive oxygen species. Endothelial function is usually evaluated by measuring the vasodilation induced by the local NO production stimulated by external mechanical or pharmacological agent. These vascular reactivity tests may be carried out in different models of experimental hypertension such as NO-deficient rats, spontaneously hypertensive rats, salt-sensitive rats, and many others. Wire myograph and pressurized myograph are the principal methods used for vascular studies. Usually, increasing concentrations of the vasodilator acetylcholine are added in cumulative manner to perform endothelium-dependent concentration-response curves. Analysis of vascular mechanics is relevant to identify arterial stiffness. Both endothelial dysfunction and vascular stiffness have been shown to be associated with increased cardiovascular risk
Levantamento da flora Pteridophyta do Parque Municipal “São Luís de Tolosa”, Rio Negro, PR
Neste trabalho realizou-se um levantamento da Flora Pterodophyta em uma parcela da floresta do Parque Ecoturístico Municipal “São Luis de Tolosa”, localizado no município de Rio Negro, Paraná. A coleta foi realizada nas bordas da Trilha Casa, próximo ao Centro Ambiental “Casa Branca”. Foram reconhecidos oito espécies de Pteridófitas, pertencentes a cinco famílias. Destas, a mais frequente foi Polipodiaceae, com três gêneros e quatro espécies: Campyloneurum nitidum (Kauf.), Nephrolepis pectinata (Willd.) Schott, Pleopeltis pleopeltifolia (Raddi) Alson; Presf e Polypodium catharinae Langsd & Fisch. A coleta foi realizada no mês de maio de 2009 e foram coletadas duas amostras de cada espécie: uma para o herbário da Universidade do Contestado – UnC/Mafra e outra para o herbário do Centro Ambiental “Casa Branca”. O parque Ecoturístico São Luis de Tolosa oferece um ambiente propício para ocorrência de grande diversidade de Pteridófitas
Evaluation of Clinical Variables Associated with Increased Carotid Intima-Media Thickness in Middle-Aged Hypertensive Women
It has been previously documented that carotid intima-media thickness (cIMT) is a predictor of cardiovascular disease. The aim of this study was to identify clinical parameters associated with an increased cIMT treated hypertensive women. Female patients (n = 116) with essential hypertension, aged 40–65 years, were included in this study. Vascular ultrasound was performed and the patients were divided into two groups according to the values of cIMT (< or ≥0.9 mm). Patients with greater cIMT presented significantly higher systolic blood pressure and pulse pressure. Serum HDL-cholesterol was significantly lower and CRP was significantly higher in the same group. There was a significant correlation between cIMT and age (r = 0.25, P = 0.007), systolic blood pressure (r = 0.19, P = 0.009), pulse pressure (r = 0.30, P = 0.001), and LDL-cholesterol (r = 0.19, P = 0.043). cIMT was correlated to CRP (r = 0.31, P = 0.007) and negatively correlated to HDL-cholesterol (r = 0.33, P = 0.001). In logistic regression, only HDL-cholesterol, CRP, and pulse pressure were shown to be independent variables associated to increased cIMT. In conclusion, pulse pressure, HDL-cholesterol, and CRP are variables correlated with cIMT in treated hypertensive women
Synthesis, thermogravimetric and high temperature X-ray diffraction analyses of zinc-substituted nickel manganites
Stoichiometric spinel phases Mn2.352xNi0.65ZnxO4 were prepared by thermal decomposition of mixed oxalate precursor powders Mn0.782aNi0.22ZnaC2O4znH2O (with 0 # a # 0.53) at 900°C. Cation-deficient phases Mn2.352xNi0.65Znxh3d/4O41d were identified in the temperature range 350–500°C. The nonstoichiometric coefficient d was found to strongly depend on the zinc content and the decomposition temperature. We showed that the introduction of zinc into the spinel phase enlarges the stability domain of the structure and inhibits oxidation at least up to 900°C. A cubic single-phase was observed for x # 1.00. The lattice parameter variation of the oxides in the composition range 0 # x # 0.60 can be explained using Poix’s method, in terms of the distribution of Zn21 cations on the tetrahedral sites. However, for higher zinc content (x . 0.6) a detailed analysis of data showed that a small fraction of Zn21 is located on octahedral sites
Development of the front-end electronics for a cost-effective PET-like detector system
Most detector systems used for positron emission particle tracking (PEPT) are
very expensive due to the use of inorganic plastic scintillators combined with
a high number of readout electronic channels. This work aims to reduce the
overall cost of a PEPT-capable detector system by using large and
cost-effective plastic scintillators and developing custom 2 x 2 silicon
photomultiplier (SiPM) arrays, preamplifiers, and discriminators. The use of
long (20 mm x 20 mm x 1000 mm) plastic scintillator bars read out with
photodetectors only at their respective ends allows an overall smaller number
of photodetectors and associated readout electronics, which in turn reduces the
overall cost of the system. In addition, the development of a custom SiPM array
and preamplifier allows a free selection of interconnection and readout, as
most commercial producers only offer specific types of interconnections and
therefore lack other connections such as serial or hybrid. Thus, several common
circuit types for SiPMs and preamplifiers were tested and compared in this
work, and it was found that a serial connection implemented in a hybrid
interconnection for the SiPMs and an inverting preamplifier based on a
high-frequency operational amplifier provided the best results for the proposed
detector system. Measured with a Na-22 source, the combination of SiPM array
and preamplifier led to a rise time of 3.7 ns and a signal amplitude of 175 mV.Comment: Published in Nuclear Instruments and Methods in Physics Research A
1057 (2023) 168767. This manuscript version is made available under the
CC-BY-NC-ND 4.0 licens
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