1,163 research outputs found

    Microcirculation in Hypertension: A Therapeutic Target to Prevent Cardiovascular Disease?

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    Arterial hypertension is a common condition worldwide and an important risk factor for cardio- and cerebrovascular events, renal diseases, as well as microvascular eye diseases. Established hypertension leads to the chronic vasoconstriction of small arteries as well as to a decreased lumen diameter and the thickening of the arterial media or wall with a consequent increased media-to-lumen ratio (MLR) or wall-to-lumen ratio (WLR). This process, defined as vascular remodeling, was firstly demonstrated in small resistance arteries isolated from subcutaneous biopsies and measured by micromyography, and this is still considered the gold-standard method for the assessment of structural alterations in small resistance arteries; however, microvascular remodeling seems to represent a generalized phenomenon. An increased MLR may impair the organ flow reserve, playing a crucial role in the maintenance and, probably, also in the progressive worsening of hypertensive disease, as well as in the development of hypertension-mediated organ damage and related cardiovascular events, thus possessing a relevant prognostic relevance. New non-invasive techniques, such as scanning laser Doppler flowmetry or adaptive optics, are presently under development, focusing mainly on the evaluation of WLR in retinal arterioles; recently, also retinal microvascular WLR was demonstrated to have a prognostic impact in terms of cardio- and cerebrovascular events. A rarefaction of the capillary network has also been reported in hypertension, which may contribute to flow reduction in and impairment of oxygen delivery to different tissues. These microvascular alterations seem to represent an early step in hypertension-mediated organ damage since they might contribute to microvascular angina, stroke, and renal dysfunction. In addition, they can be markers useful in monitoring the beneficial effects of antihypertensive treatment. Additionally, conductance arteries may be affected by a remodeling process in hypertension, and an interrelationship is present in the structural changes in small and large conductance arteries. The review addresses the possible relations between structural microvascular alterations and hypertension-mediated organ damage, and their potential improvement with antihypertensive treatment

    Estrogen signaling in the cardiovascular system

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    Estrogen exerts complex biological effects through the two isoforms of estrogen receptors (ERs): ERα and ERβ. Whether through alteration of gene expression or rapid, plasma membrane-localized signaling to non-transcriptional actions, estrogen-activated ERs have significant implications in cardiovascular physiology. 17-β-estradiol (E2) generally has a protective property on the vasculature. Estrogen treatment is anti-atherogenic, protecting injured endothelial surfaces and lowering LDL oxidation in animal models. Increased NO production stimulated by E2 results in vasodilation of the coronary vascular bed, and involves rapid activation of phosphotidylinositol-3 kinase (PI3K)/Akt signaling to eNOS in carotid and femoral arteries. Both isoforms of ERs impact various vascular functions, modulating ion channel integrity, mitigating the response to arterial injury, inducing vasodilation, and preventing development of hypertension in animal models. In addition to reducing afterload by vasodilation, ERs have a direct antihypertrophic effect on the myocardium. E2-activated ERs (E2/ER) antagonize the hypertrophic pathway induced by vasoactive peptides such as angiotensin II by activating PI3K, subsequent MICIP gene expression, leading to the inhibition of calcineurin activity and the induction of hypertrophic genes. In models of ischemia-reperfusion, E2/ER is antiapoptotic for cardiomyocytes, exerting the protective actions via PI3K and p38 MAP kinases and suppressing the generation of reactive oxygen species. In sum, E2-activated ERs consistently and positively modulate multiple aspects of the cardiovascular system

    Modified percutaneous ethanol injection of parathyroid adenoma in primary hyperparathyroidism.

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    Surgery is the treatment of choice for symptomatic primary hyperparathyroidism; unlikely few patients do not meet established surgical criteria or have comorbid conditions that prohibit surgery. In these subjects, medical therapy alone offers little hope for a sustained long normocalcemic period. However percutaneous ethanol injection (PEI) may represent an alternative therapeutic procedure. It is currently in use for the treatment of secondary or tertiary hyperparathyroidism, however, few studies or case reports suggest it for the treatment of primary hyperparathyroidism. Moreover, little information is available about the long-term follow-up, where incomplete necrosis or the spreading of ethanol in the surrounding tissues is often reported. We believe that many of the side effects could be correlated to procedure itself. Taking these experiences into account, we have reasoned that in order to limit these side effects, we had to modify the standard PEI procedure. We reported this preliminary experience describing our modified PEI procedure

    Prognostic value of thyrotropin receptor antibodies (TRAb) in Graves' disease: a 120 months prospective study

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    In most trials, at least 30-60% of patients with Graves' disease treated with antithyroid drugs relapse within 2 years after therapy withdrawal. At present, there are no prognostic parameters available early in treatment to indicate patients likely to achieve long-term remission. Because thyrotropin receptor autoantibodies (TRAb) are specific for Graves' disease, we evaluated the ability of their levels and of their rate of change to predict long-term prognosis. In our study 216 consecutive patients with newly diagnosed Graves' disease started a therapy with methimazole. Patients were treated until they achieved euthyroidism and TRAb were measured at 6-month intervals throughout a follow up of 120 months. Our study demonstrated that at the onset of hyperthyroidism patients' age, sex, fT4 levels and goiter size had no prognostic value in predicting long-term prognosis (respectively p = 0.79; p = 0.98; p = 0.83; p = 0.89). On the contrary, at the time of diagnosis TRAb titer was a good predictor of the final outcome (p<0.001); a titer equal to (or) more than 46.5 UI/L could identify patients who had never achieved long-term remission with a sensitivity of 52% and a specificity of 78%. Also fall rate of TRAb at 6 months of follow up and after therapy withdrawal were useful to predict the final outcome (p<0.001). At 6 months of follow up the time of therapy withdrawal, a decrease of TRAb lower than 52.3% or even its increase could identify patients who had never achieved permanent remission with a sensitivity of 55% and a specificity of 79.1%. No single parameter among TRAb, satisfactory identified a sub-set of patients who achieved long remission. Accordingly to our data, the best result in predicting long term remission is probably given by the presence of at least one of the two features evaluated at 6 months (TRAb titer and/or percentage of TRAb fall rate), with a sensitivity of 63% and specificity of 88%. TRAb titers evaluated both at the onset of hyperthyroidism that at 6 months of therapy or their rate of fall at 6 months and at ATD withdrawal are predictors of outcome. However, the presence of at least one, between titers of TRAb or their rate of fall at six months, resulted to be the best predictor of remission with the higher sensitivity and specificity

    Fine needle cytology of complex thyroid nodules.

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    OBJECTIVE: To evaluate whether a preliminary aspiration (ASP) of the cystic component and/or using spinal needles in complex thyroid nodules (CTN) could improve the adequacy of cytological sampling. METHODS: Between January 2004 and December 2006, 386 consecutive patients with CTN were enrolled in this prospective investigation. Ultrasound (US) fine needle aspiration cytology (FNAC) of the solid component of the nodule (one nodule per patient) was performed using two different 25 gauge needles, with (Yale Spinal, YS) or without (Neolus, NS) a stylet, in alternate sequence on consecutive patients. In addition, a subgroup of patients presenting larger cystic component (approximately 50%) was submitted to total aspiration of the cystic component (ASP+) or not submitted (ASP-) before US-FNAC, in alternate sequence within each needle type group. All the samplings were performed by a single endocrinologist. RESULTS: Adequate specimens were observed in 163 (84.5%) and 183 (94.8%) nodules investigated by NS and YS respectively. Sampling with the stylet needle was associated with an overall significant reduction of non-diagnostic specimens (15.5% vs 5.2% by NS and YS respectively, P < 0.001). The favourable result obtained with YS was independent from preliminary aspiration of the cystic component (ASP+: 14.8% vs 5.7% by NS and YS; ASP-: 16.2% vs 4.8%, not significant). A logistic regression analysis, taking into account nodule size and presence of intranodal vascularity at eco-colour evaluation of the solid component, confirmed that needle type was the only significant predictor of successful sampling (odds ratio 3.6 (95% confidence interval 1.7-7.6), P < 0.001). CONCLUSIONS: Our data show that adopting stylet needles to perform FNAC in CTN may significantly improve the percentage of adequate sampling. On the other hand, preliminary aspiration of CTN with large cystic component does not add any advantage
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