1000 resultados para Col·loides, Hipotensió arterial, Anestèsia epidural, Part


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Hailey-Hailey disease (HHD) is an autosomal dominant disorder characterized by suprabasal cutaneous cell separation (acantholysis) leading to the development of erosive and oozing skin lesion. Micro RNAs (miRNAs) are endogenous post-transcriptional modulators of gene expression with critical functions in health and disease. Here, we evaluated whether the expression of specific miRNAs may play a role in the pathogenesis of HHD. Here, we report that miRNAs are expressed in a non-random manner in Hailey-Hailey patients. miR-125b appeared a promising candidate for playing a role in HHD manifestation. Both Notch1 and p63 are part of a regulatory signalling whose function is essential for the control of keratinocyte proliferation and differentiation and of note, the expression of both Notch1 and p63 is downregulated in HHD-derived keratinocytes. We found that both Notch1 and p63 expression is strongly suppressed by miR-125b expression. Additionally, we found that miR-125b expression is increased by an oxidative stress-dependent mechanism. Our data suggest that oxidative stress-mediated induction of miR-125b plays a specific role in the pathogenesis of HHD by regulating the expression of factors playing an important role in keratinocyte proliferation and differentiation.

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Abstract Introduction The primary function of the contractile vascular smooth muscle cells (cVSMCs) is the regulation of the vascular contractility which means the adaptation of the vascular tonus in response to the modulation of the blood pressure and blood flow. The cVSMCs are essentially quiescent, and therefore their synthesis rate is very limited. They are characterized by the expression of contractile proteins specific to the muscular tissue including myosin, h-­‐caldesmon and <-­‐smooth muscle actin (〈-­‐SMA). These contractile cells are strongly represented in the media layer of the arterial wall and, in a smaller proportion, of the vein wall. Their typical stretched-­‐out morphology allows recognizing them by a histological analysis. They do not produce any extracellular matrix (ECM), and do not migrate through the different layers of the vessel wall, and are not directly involved in the development of intimal hyperplasia (IH). Neointimal formation occurs after endothelial disruption leading to complex molecular and biological mechanisms. The de-­‐differentiation of cVSMCs into synthetic VSMCs (sVSMCs) is mentioned as a key element. These non mature cells are able to proliferate and produce ECM. The characterization of the vascular smooth muscle cells (VSMCs) from healthy and stenosed vascular tissues will contribue to the understanding of the different biological processes leading to IH and will be useful for the development of new therapies to interfere with the cVSMCs growth and migration. The aim of our research was to quantify the proportion of cVSMCs and sVSMCs into the healthy and pathologic human blood vessel wall and to characterize their phenotype. Methods We selected 23 specimens of arterial and venous segments from 18 patients. All these specimens were stored in the biobank from the thoracic and vascular surgery departement. 4 groups were designed (group 1 :arteries without lesions (n=3) ;group 2 : veins without lesions (n=1); group 3: arteries with stenosis (n=9); group 4: veins with stenosis (n=10)). Histology: 5µm-­‐sections were made from each sample embedded in paraffin wax and further stained with hematoxylin & eosin (HE), Van Gieson's stain (VGEL) and Masson's Trichrome (TMB). Pathologic tissues were defined using the label that was given to the macroscopic samples by the surgeon and also, based on the histological analysis with HE and VGEL evaluating the presence of a thickened intima. The same was done to the control samples evaluating the absence of thickening. Immunohistochemistry : The primary antibodies were used :〈-­‐SMA, vimentin, h-­‐ caldesmon, calponin, smooth muscle-myosin heavy chain (SM-­‐MHC), tropomyosin-­‐4, retinol binding protein-­‐1 (RBP-­‐1), nonmuscle-­‐myosin heavy chain-­‐B (NM-­‐MHC-­‐B), Von Willebrand factor (VWF). A semi-­‐quantitative assessment of the intensity of each sample stained was performed. Western Blot : Segments of arteries and veins were analyzed using the following primary antibodies :〈-­‐SMA, Calponin, SM-­‐MHC, NM-­‐MHC-­‐B. The given results were then normalized with tubulin. Results Our data showed that, when using immunohistochemistry analysis we found that〈-­‐SMA was mostly expressed in control arteries, whereas NM-­‐MHC-­‐B in the pathologic ones. Using SM-­‐MHC, calponin, vimentin and caldesmon we found no significative differences in the expression of these proteins in the control and in the pathologic samples. Western Blot analysis showed an inverse correlation between healthy and pathological samples as <-­‐ SMA was more expressed in the pathological samples, while NM-­‐MHC-­‐B in the control group; SM-­‐MHC and calponin were mostly expressed in the pathologic samples. Conclusion Our study showed no clear differences between stenotic and control arterial and venous segments using semi-­‐quantitative assessement by immunohistochemistry. Western Blot showed a significant increased expression of 〈-­‐SMA, calponin and SM-­‐MHC in the arteries with stenosis, while NM-­‐MHC-­‐B was mostly expressed in the arteries without lesions. Further studies are needed to track the lineage of VSMCs to understand the mechanisms leading toIH.

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Conventional coronary magnetic resonance angiography (MRA) techniques display the coronary blood-pool along with the surrounding structures, including the myocardium, the ventricular and atrial blood-pool, and the great vessels. This representation of the coronary lumen is not directly analogous to the information provided by x-ray coronary angiography, in which the coronary lumen displayed by iodinated contrast agent is seen. Analogous "luminographic" data may be obtained using MR arterial spin tagging (projection coronary MRA) techniques. Such an approach was implemented using a 2D selective "pencil" excitation for aortic spin tagging in concert with a 3D interleaved segmented spiral imaging sequence with free-breathing, and real-time navigator technology. This technique allows for selective 3D visualization of the coronary lumen blood-pool, while signal from the surrounding structures is suppressed.

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En aquest TFC s'ha proposat dissenyar i implementar en llenguatge Java un sistema segur de descàrrega anònima de fitxers. Per fer aquesta tasca es proposa un conjunt d'aplicacions web que es s'intercanviaran dades en format XML de forma segura, sempre sota protocol HTTPS i mantenint la integritat, autenticitat i autenticació de les parts amb l'ajut d'un PKI.

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The Alcohol MOT is designed to support those working in primary care to carry out alcohol brief interventions. There is extensive evidence to show that primary care-based brief interventions are very effective at reducing drinking at both hazardous and harmful levels. MOT Part 1 enables patients to work out if they are drinking at hazardous or harmful levels. MOT Part 2 helps motivate and support patients to reduce their drinking. Both tools are designed so that a practitioner can work through them with a patient, or a patient can work through them alone.

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The Alcohol MOT is designed to support those working in primary care to carry out alcohol brief interventions. There is extensive evidence to show that primary care-based brief interventions are very effective at reducing drinking at both hazardous and harmful levels. MOT Part 1 enables patients to work out if they are drinking at hazardous or harmful levels. MOT Part 2 helps motivate and support patients to reduce their drinking. Both tools are designed so that a practitioner can work through them with a patient, or a patient can work through them alone.

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The aim of the present report is to outline, in concise from, the changes in vascular structure which accompany hypertension. Consideration will be given to their potential contribution to hypertensive end organ damage. In so doing, it is important to consider both the macrovascular and microvascular levels, because interactions between them are presently believed to be critically important. The links between hypertension and the pathogenesis of arteriosclerosis fall outside the scope of this short review.

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We present a system for dynamic network resource configuration in environments with bandwidth reservation and path restoration mechanisms. Our focus is on the dynamic bandwidth management results, although the main goal of the system is the integration of the different mechanisms that manage the reserved paths (bandwidth, restoration, and spare capacity planning). The objective is to avoid conflicts between these mechanisms. The system is able to dynamically manage a logical network such as a virtual path network in ATM or a label switch path network in MPLS. This system has been designed to be modular in the sense that in can be activated or deactivated, and it can be applied only in a sub-network. The system design and implementation is based on a multi-agent system (MAS). We also included details of its architecture and implementation

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INTRODUCTION Hemodynamic resuscitation should be aimed at achieving not only adequate cardiac output but also sufficient mean arterial pressure (MAP) to guarantee adequate tissue perfusion pressure. Since the arterial pressure response to volume expansion (VE) depends on arterial tone, knowing whether a patient is preload-dependent provides only a partial solution to the problem. The objective of this study was to assess the ability of a functional evaluation of arterial tone by dynamic arterial elastance (Ea(dyn)), defined as the pulse pressure variation (PPV) to stroke volume variation (SVV) ratio, to predict the hemodynamic response in MAP to fluid administration in hypotensive, preload-dependent patients with acute circulatory failure. METHODS We performed a prospective clinical study in an adult medical/surgical intensive care unit in a tertiary care teaching hospital, including 25 patients with controlled mechanical ventilation who were monitored with the Vigileo(®) monitor, for whom the decision to give fluids was made because of the presence of acute circulatory failure, including arterial hypotension (MAP ≤65 mmHg or systolic arterial pressure <90 mmHg) and preserved preload responsiveness condition, defined as a SVV value ≥10%. RESULTS Before fluid infusion, Ea(dyn) was significantly different between MAP responders (MAP increase ≥15% after VE) and MAP nonresponders. VE-induced increases in MAP were strongly correlated with baseline Ea(dyn) (r(2) = 0.83; P < 0.0001). The only predictor of MAP increase was Ea(dyn) (area under the curve, 0.986 ± 0.02; 95% confidence interval (CI), 0.84-1). A baseline Ea(dyn) value >0.89 predicted a MAP increase after fluid administration with a sensitivity of 93.75% (95% CI, 69.8%-99.8%) and a specificity of 100% (95% CI, 66.4%-100%). CONCLUSIONS Functional assessment of arterial tone by Ea(dyn), measured as the PVV to SVV ratio, predicted arterial pressure response after volume loading in hypotensive, preload-dependent patients under controlled mechanical ventilation.

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A better integration of the information conveyed by traces within intelligence-led framework would allow forensic science to participate more intensively to security assessments through forensic intelligence (part I). In this view, the collection of data by examining crime scenes is an entire part of intelligence processes. This conception frames our proposal for a model that promotes to better use knowledge available in the organisation for driving and supporting crime scene examination. The suggested model also clarifies the uncomfortable situation of crime scene examiners who must simultaneously comply with justice needs and expectations, and serve organisations that are mostly driven by broader security objectives. It also opens new perspective for forensic science and crime scene investigation, by the proposal to follow other directions than the traditional path suggested by dominant movements in these fields.

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Our objective was to analyze the prevalence of peripheral arterial disease (PAD) in HIV patients at risk and to compare them with the general population. All HIV patients older than 50 years who attended our unit from October 2005-July 2006 and all persons attending for an annual medical checkup at an employees' insurance association during the same period were invited to participate in the study. Of the latter (n = 407), a person of the same sex and age (+/-5 years) was included for each HIV patient. PAD was assessed by the ankle-brachial index (ABI) in all subjects, and all completed the Edinburgh questionnaire. Ninety-nine HIV patients and 99 persons from the general population of the same age and sex were included in the study. The HIV patients had a greater prevalence of dyslipidemia, diabetes, and PAD, which was symptomatic in five of them and in one subject from the general population. Patients with HIV infection older than 50 had a high prevalence of PAD, and as it was asymptomatic in half the cases, an ABI may be performed in this population to actively look for PAD. Control of cardiovascular risk factors and the use of such drugs as platelet antiaggregation agents should therefore be optimized in this population.

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To assess the behavior of the arterial wall in hypertensive patients, we developed a noninvasive ultrasonic device. Simultaneous recordings of internal diameter and blood pressure over the whole cardiac cycle are used to establish compliance-pressure curves. Blood pressure, which is a co-determinant of compliance, is thus taken into account. This method allows one to compare arteries from patients with different blood pressures. Arterial compliance and distensibility were first investigated in healthy young volunteers administered either lisinopril (20 mg), atenolol (100 mg) or nitrendipine (20 mg) once a day. After 8 days of treatment, only lisinopril was found to increase arterial compliance. Subsequently, we compared arterial diameter- and distensibility-pressure curves from newly diagnosed and untreated hypertensive patients with those of matched normotensive control patients. Diameter-pressure curves did not differ significantly between the groups and distensibility was not reduced. Similar findings were later obtained in an animal model, when mechanical properties of carotid arteries were compared between spontaneously hypertensive rats and normotensive counterparts (Wistar-Kyoto rats). These results, although interesting by providing noninvasive information on the elastic response of the wall, call for further development of the technique to be able to measure arterial wall thickness. Stress-strain relationship could ultimately be established to thoroughly characterize physical properties of blood vessel walls.

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During recovery from a maximal or submaximal aerobic exercise, augmentation of central (aortic) systolic pressure by reflected pressure waves is blunted in healthy humans. However, the extent to which reflected pressure waves modify the central pulse in diastole in these conditions remains unknown. We evaluated systolic and diastolic central reflected waves in 11 endurance-trained athletes on recovery from a maximal running test on a treadmill (treadmill-max) and a 4000 m run in field conditions. On both occasions in each subject, the radial pulse was recorded with applanation tonometry in the resting preexercise state and then 5, 15, 25, 35, and 45 min after exercise termination. From the central waveform, as reconstructed by application of a generalized transfer function, we computed a systolic (AIx) and a diastolic index (AId) of pressure augmentation by reflections. At 5 min, both indices were below preexercise. At further time-points, AIx remained low, while AId progressively increased, to overshoot above preexercise at 45 min. The same behavior was observed with both exercise types. Beyond the first few minutes of recovery following either maximal or submaximal aerobic exercise, reflected waves selectively augment the central pressure pulse in diastole, at least in endurance-trained athletes.

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Background: Transcatheter arterial chemoembolization (TACE) has been shown to offer a survival benefit for patients with intermediate-stage hepatocellular carcinoma (HCC). A widely accepted TACE regimen includes the administration of a doxorubicin-in-oil emulsion followed by gelatine sponge particles. Recently, a drug-eluting bead (DEB) has been developed to enhance drug delivery to the tumor and reduce its systemic availability. Purpose of this randomized trial was to compare conventional TACE with DEB-TACE for the treatment of intermediate-stage HCC in patients with cirrhosis. Methods: Two hundred and twelve patients (185 males and 27 females; mean age, 67 years) with Child-Pugh A or B liver cirrhosis and large and/or multinodular, unresectable HCC were randomized to receive DEB-TACE (DC Bead; Biocompatibles, UK) uploaded with doxorubicin or conventional TACE with doxorubicin, lipiodol, and gelatin sponge particles. Randomization was stratified according to Child Pugh status (A or B), performance status (ECOG 0 or 1), bilobar disease (yes or no) and prior curative treatment (yes or no). Tumor response at 6 months was the primary study endpoint. An independent, blinded review of magnetic resonance imaging studies was conducted to assess tumor response according to amended RECIST criteria. Results: DEB-TACE with doxorubicin showed a higher rate of complete response, objective response and disease control compared with conventional TACE (27% vs 22%; 52% vs 44%; and 63% vs 52%, respectively; p>0.05). Patients with Child Pugh B, ECOG 1, bilobar disease and recurrence following curative treatment showed a significant increase in objective response (p=0.038) compared to the control. There was a marked reduction in serious liver toxicity in patients treated with DEB-TACE. The rate of doxorubicin related side effects was significantly lower (p=0.0001) in the DEB-TACE group compared with the conventional TACE group. Conclusions: DEB-TACE with doxorubicin is safe and effective in the treatment of intermediate-stage HCC and may offer benefit to patients with more advanced disease.