1000 resultados para Regional vascular conductance
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Dendritic cells (DCs) are antigen (Ag)-presenting cells that activate and stimulate effective immune responses by T cells, but can also act as negative regulators of these responses and thus play important roles in immune regulation. Pro-angiogenic vascular endothelial growth factor (VEGF) has been shown to cause defective DC differentiation and maturation. Previous studies have demonstrated that the addition of VEGF to DC cultures renders these cells weak stimulators of Ag-specific T cells due to the inhibitory effects mediated by VEGF receptor 1 (VEGFR1) and/or VEGFR2 signalling. As the enzyme indoleamine 2,3-dioxygenase (IDO) is recognised as an important negative regulator of immune responses, this study aimed to investigate whether VEGF affects the expression of IDO by DCs and whether VEGF-matured DCs acquire a suppressor phenotype. Our results are the first to demonstrate that VEGF increases the expression and activity of IDO in DCs, which has a suppressive effect on Ag-specific and mitogen-stimulated lymphocyte proliferation. These mechanisms have broad implications for the study of immunological responses and tolerance under conditions as diverse as cancer, graft rejection and autoimmunity.
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Sección "Buenas prácticas en gestión clínica"
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This article examines the relationship between political parties and regional presidents in Italy and Spain, adopting a comparative case study approach based on extensive archival analysis and in-depth interviews with regional politicians. The findings confirm a strong pattern of growing presidentialism at regional level, regardless of whether there are formal mechanisms for direct election, and regardless of the partisan composition of regional government. Regional presidents tend to exert their growing power through a personalised control of regional party organisations, rather than governing past parties in a direct appeal to the electorate. Nevertheless, parties can still present a significant constraint on regional presidents, so successful regional presidents tend to maintain a mediating form of leadership and fully exploit the opportunities for party patronage to build up their support and smooth governing tensions. An autonomist drive helps presidents hold together disparate coalitions or loose parties at regional level, but their lack of internal coherence presents major problems when it comes to political succession.
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Mycobacterium bovis is the causative agent of bovine tuberculosis (TB), a disease that affects approximately 5% of Argentinean cattle. Among the molecular methods for genotyping, the most convenient are spoligotyping and variable number of tandem repeats (VNTR). A total of 378 samples from bovines with visible lesions consistent with TB were collected at slaughterhouses in three provinces, yielding 265 M. bovis spoligotyped isolates, which were distributed into 35 spoligotypes. In addition, 197 isolates were also typed by the VNTR method and 54 combined VNTR types were detected. There were 24 clusters and 27 orphan types. When both typing methods were combined, 98 spoligotypes and VNTR types were observed with 27 clusters and 71 orphan types. By performing a meta-analysis with previous spoligotyping results, we identified regional and temporal trends in the population structure of M. bovis. For SB0140, the most predominant spoligotype in Argentina, the prevalence percentage remained high during different periods, varying from 25.5-57.8% (1994-2011). By contrast, the second and third most prevalent spoligotypes exhibited important fluctuations. This study shows that there has been an expansion in ancestral lineages as demonstrated by spoligotyping. However, exact tandem repeat typing suggests dynamic changes in the clonal population of this microorganism.
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Cerebral malaria (CM) is a life-threatening complication of Plasmodium falciparum malaria that continues to be a major global health problem. Brain vascular dysfunction is a main factor underlying the pathogenesis of CM and can be a target for the development of adjuvant therapies for the disease. Vascular occlusion by parasitised red blood cells and vasoconstriction/vascular dysfunction results in impaired cerebral blood flow, ischaemia, hypoxia, acidosis and death. In this review, we discuss the mechanisms of vascular dysfunction in CM and the roles of low nitric oxide bioavailability, high levels of endothelin-1 and dysfunction of the angiopoietin-Tie2 axis. We also discuss the usefulness and relevance of the murine experimental model of CM by Plasmodium berghei ANKA to identify mechanisms of disease and to screen potential therapeutic interventions.
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PURPOSE: To evaluate whether anti-vascular endothelial growth factor (VEGF) neutralizing antibodies injected in the vitreous of rat eyes influence retinal microglia and macrophage activation. To dissociate the effect of anti-VEGF on microglia and macrophages subsequent to its antiangiogenic effect, we chose a model of acute intraocular inflammation. METHODS: Lewis rats were challenged with systemic lipopolysaccharide (LPS) injection and concomitantly received 5 µl of rat anti-VEGF-neutralizing antibody (1.5 mg/ml) in the vitreous. Rat immunoglobulin G (IgG) isotype was used as the control. The effect of anti-VEGF was evaluated at 24 and 48 h clinically (uveitis scores), biologically (cytokine multiplex analysis in ocular media), and histologically (inflammatory cell counts on eye sections). Microglia and macrophages were immunodetected with ionized calcium-binding adaptor molecule 1 (IBA1) staining and counted based on their differential shapes (round amoeboid or ramified dendritiform) on sections and flatmounted retinas using confocal imaging and automatic quantification. Activation of microglia was also evaluated with inducible nitric oxide synthase (iNOS) and IBA1 coimmunostaining. Coimmunolocalization of VEGF receptor 1 and 2 (VEGF-R1 and R2) with IBA1 was performed on eye sections with or without anti-VEGF treatment. RESULTS: Neutralizing rat anti-VEGF antibodies significantly decreased ocular VEGF levels but did not decrease the endotoxin-induced uveitis (EIU) clinical score or the number of infiltrating cells and cytokines in ocular media (interleukin [IL]-1β, IL-6, tumor necrosis factor [TNF]-α, and monocyte chemoattractant protein [MCP]-1). Eyes treated with anti-VEGF showed a significantly decreased number of activated microglia and macrophages in the retina and the choroid and decreased iNOS-positive microglia. IBA1-positive cells expressed VEGF-R1 and R2 in the inflamed retina. CONCLUSIONS: Microglia and macrophages expressed VEGF receptors, and intravitreous anti-VEGF influenced the microglia and macrophage activation state. Taking into account that anti-VEGF drugs are repeatedly injected in the vitreous of patients with retinal diseases, part of their effects could result from unsuspected modulation of the microglia activation state. This should be further studied in other ocular pathogenic conditions and human pathology.
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This research investigates differences in the stereotype content of immigrant groups between linguistic regions. We expected that immigrant groups who speak the local language of a specific linguistic region would be perceived as more competitive within this region than in another linguistic region. Further, we expected these differences would underlie regional differences in stereotype content, albeit only for the warmth dimension. Predictions were tested in the two largest linguistic regions of Switzerland. As expected, in the German-speaking region, locals perceived German immigrants as more competitive and thus as less warm, whereas in the French-speaking region, locals perceived French immigrants as more competitive and, consequently, as less warm. So, paradoxically, immigrants with strong integration potential are particularly disliked because they are regarded as direct competitors.
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Background: Understanding the true prevalence of lymphangioleiomyomatosis (LAM) is important in estimating disease burden and targeting specific interventions. As with all rare diseases, obtaining reliable epidemiological data is difficult and requires innovative approaches.Aim: To determine the prevalence and incidence of LAM using data from patient organizations in seven countries, and to use the extent to which the prevalence of LAM varies regionally and nationally to determine whether prevalence estimates are related to health-care provision.Methods: Numbers of women with LAM were obtained from patient groups and national databases from seven countries (n = 1001). Prevalence was calculated for regions within countries using female population figures from census data. Incidence estimates were calculated for the USA, UK and Switzerland. Regional variation in prevalence and changes in incidence over time were analysed using Poisson regression and linear regression.Results: Prevalence of LAM in the seven countries ranged from 3.4 to 7.8/million women with significant variation, both between countries and between states in the USA. This variation did not relate to the number of pulmonary specialists in the region nor the percentage of population with health insurance, but suggests a large number of patients remain undiagnosed. The incidence of LAM from 2004 to 2008 ranged from 0.23 to 0.31/million women/per year in the USA, UK and Switzerland.Conclusions: Using this method, we have found that the prevalence of LAM is higher than that previously recorded and that many patients with LAM are undiagnosed.
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Regional policies aiming to attract new firms are largely based on evidence that originates from Europe, the USA and Japan. This may raise doubts about the usefulness of such policies when applied to developing economies. This paper addresses this issue by providing estimates of the determinants of firm entry in the Argentinean provinces. We find that most of the determinants used in previous studies analysing developed countries are still relevant. However, there is a need for additional explanatory variables that reflect the specificities of developing economies. Key words: firm entry, regional economics, Argentina. JEL: R12; R30; C33
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CONTEXT Soluble TNF-like weak inducer of apoptosis (sTWEAK) is generated by the intracellular proteolytic cleavage of full-length membrane-bound TNF-like weak inducer of apoptosis (mTWEAK). sTWEAK levels are reduced in diseases with an inflammatory component. Additionally, sTWEAK hampers TNFα activity in human cells. OBJECTIVES The objectives of the study were as follows: 1) to determine circulating sTWEAK in severe obesity and after bariatric surgery; 2) to study m/sTWEAK and its receptor fibroblast growth factor-inducible 14 (Fn14) protein expression in sc adipose tissue (SAT) of severely obese subjects, in SAT stromal vascular fraction (SVF), and isolated adipocytes and in human monocyte-derived macrophages; and 3) to explore, on human adipocytes, the sTWEAK effect on TNFα proinflammatory activity. DESIGN sTWEAK levels were measured in cohort 1: severely obese subjects (n = 23) and a control group (n = 35); and in cohort 2: (n = 23) severely obese subjects before and after surgery. The m/sTWEAK and Fn14 expressions were determined in SAT biopsies, SVF, and isolated adipocytes from severely obese and control subjects and in human monocyte-derived macrophages. In human primary cultured adipocytes, sTWEAK pretreated and TNFα challenged, IL-6, IL-8, and adiponectin protein and gene expressions were determined and nuclear factor-κ B and MAPK signaling analyzed. RESULTS sTWEAK levels were reduced in severely obese subjects. After surgery, sTWEAK levels rose in 69% of patients. mTWEAK protein expression was increased in SAT and SVF of severely obese subjects, whereas Fn14 was up-regulated in isolated adipocytes. M2 human monocyte-derived macrophages overexpress mTWEAK. In human adipocytes, sTWEAK down-regulates TNFα cytokine production by hampering TNFα intracellular signaling events. CONCLUSION The decrease of sTWEAK in severely obese patients may favor the proinflammatory activity elicited by TNFα.
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The screening of vascular pathologies in physician offices starts with precise medical history and clinical exam. Tools like the Edinburgh Claudication Questionnaire for the peripheral artery disease or the Wells score for the probability of a thromboembolic event are useful. The measure of the ankle brachial index, the D-dimers or any other biological screening are complementary. In the presence of pathological features, it is recommended to organise a specialised consultation in order to precise diagnosis, treatment and follow-up. The screening of a vascular disease is interesting not only for the management of local symptoms, but also for the associated systemic pathologies to provide a preventive medicine of good quality.
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AIM: Patients with non-insulin-dependent diabetes mellitus (NIDDM) are at increased cardiovascular risk due to an accelerated atherosclerotic process. The present study aimed to compare skin microvascular function, pulse wave velocity (PWV), and a variety of hemostatic markers of endothelium injury [von Willebrand factor (vWF), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (t-PA), tissue factor pathway inhibitor (TFPI), and the soluble form of thrombomodulin (s-TM)] in patients with NIDDM. METHODS: 54 patients with NIDDM and 38 sex- and age-matched controls were studied. 27 diabetics had no overt micro- and/or macrovascular complications, while the remainder had either or both. The forearm skin blood flow was assessed by laser-Doppler imaging, which allowed the measurement of the response to iontophoretically applied acetylcholine (endothelium-dependent vasodilation) and sodium nitroprusside (endothelium-independent vasodilation), as well as the reactive hyperemia triggered by the transient occlusion of the circulation. RESULTS: Both endothelial and non-endothelial reactivity were significantly blunted in diabetics, regardless of the presence or the absence of vascular complications. Plasma vWF, TFPI and s-TM levels were significantly increased compared with controls only in patients exhibiting vascular complications. Concentrations of t-PA and PAI-1 were significantly increased in the two groups of diabetics versus controls. CONCLUSION: In NIDDM, both endothelium-dependent and -independent microvascular skin reactivity are impaired, whether or not underlying vascular complications exist. It also appears that microvascular endothelial dysfunction is not necessarily associated in NIDDM with increased circulating levels of hemostatic markers of endothelial damage known to reflect a hypercoagulable state.