31 research outputs found
Endothelial Dysfunction: Associations with Exposure to Ambient Fine Particles in Diabetic Individuals
BACKGROUND: Exposure to fine airborne particulate matter [<= 2.5 mu m in aerodynamic diameter (PM2.5)] has been associated with cardiovascular and hematologic effects, especially in older people with cardiovascular disease. Some epidemiologic studies suggest that adults with diabetes also may be a particularly susceptible population. OBJECTIVES: The purpose of this study was to analyze the short-term effects of ambient PM2.5 on markers of endothelial function in diabetic volunteers.METHODS: We conducted a prospective panel study in 22 people with type 2 diabetes mellitus in Chapel Hill, North Carolina (USA), from November 2004 to December 2005. We acquired daily measurements of PM2.5 and meteorologic data at central monitoring sites. On 4 consecutive days, we measured endothelial function by brachial artery ultrasound in all participants and by pulsewave measurements in a subgroup. Data were analyzed using additive mixed models with a random participant effect and adjusted for season, day of the week, and meteorology. RESULTS: Flow-mediated dilatation decreased in association with PM2.5 during the first 24 hr, whereas small-artery elasticity index decreased with a delay of 1 and 3 days. These PM2.5-associated decrements in endothelial function were greater among participants with a high body mass index, high glycosylated hemoglobin Ale, low adiponectin, or the null polymorphism of glutathione S-transferase M1. However, high levels of myeloperoxidase on the examination day led to strongest effects on endothelial dysfunction. CONCLUSIONS: These data demonstrate that PM2.5 exposure may cause immediate endothelial dysfunction. Clinical characteristics associated with insulin resistance were associated with enhanced effects of PM on endothelial function. In addition, participants with greater oxidative potential seem to be more susceptible
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Reāevaluation of sodium, potassium and calcium salts of fatty acids (E 470a) and magnesium salts of fatty acids (E 470b) as food additives
The EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion reāevaluating the safety of sodium, potassium and calcium salts of fatty acids (E 470a) and magnesium salts of fatty acids (E 470b) when used as food additives. In 1991, the Scientific Committee on Food (SCF) established a group acceptable daily intake (ADI) ānot specifiedā for the fatty acids (myristicā, stearicā, palmiticā and oleic acid) and their salts. The sodium, potassium, calcium and magnesium salts of fatty acids are expected to dissociate in the gastrointestinal tract to fatty acid carboxylates and their corresponding cations. There were no data on subchronic toxicity, chronic toxicity, reproductive and developmental toxicity of the salts of fatty acids. There was no concern for mutagenicity of calcium caprylate, potassium oleate and magnesium stearate. From a carcinogenicity study with sodium oleate, a no observed adverse effect level (NOAEL) could not be identified but the substance was considered not to present a carcinogenic potential. Palmiticā and stearic acid which are the main fatty acids in E 470a and E 470b were already considered of no safety concern in the reāevaluation of the food additive E 570. The fatty acid moieties of E 470a and E 470b contributed maximally for 5% to the overall intake of saturated fatty acids from all dietary sources. Overall, the Panel concluded that there was no need for a numerical ADI and that the food additives sodium, potassium, calcium and magnesium salts of fatty acids (E 470a and E 470b) were of no safety concern at the reported uses and use levels
Endothelial Dysfunction: Associations with Exposure to Ambient Fine Particles in Diabetic Individuals
BackgroundExposure to fine airborne particulate matter [ā¤2.5 Ī¼m in aerodynamic diameter (PM2.5)] has been associated with cardiovascular and hematologic effects, especially in older people with cardiovascular disease. Some epidemiologic studies suggest that adults with diabetes also may be a particularly susceptible population.ObjectivesThe purpose of this study was to analyze the short-term effects of ambient PM2.5 on markers of endothelial function in diabetic volunteers.MethodsWe conducted a prospective panel study in 22 people with type 2 diabetes mellitus in Chapel Hill, North Carolina (USA), from November 2004 to December 2005. We acquired daily measurements of PM2.5 and meteorologic data at central monitoring sites. On 4 consecutive days, we measured endothelial function by brachial artery ultrasound in all participants and by pulsewave measurements in a subgroup. Data were analyzed using additive mixed models with a random participant effect and adjusted for season, day of the week, and meteorology.ResultsFlow-mediated dilatation decreased in association with PM2.5 during the first 24 hr, whereas small-artery elasticity index decreased with a delay of 1 and 3 days. These PM2.5-associated decrements in endothelial function were greater among participants with a high body mass index, high glycosylated hemoglobin A1c, low adiponectin, or the null polymorphism of glutathione S-transferase M1. However, high levels of myeloperoxidase on the examination day led to strongest effects on endothelial dysfunction.ConclusionsThese data demonstrate that PM2.5 exposure may cause immediate endothelial dysfunction. Clinical characteristics associated with insulin resistance were associated with enhanced effects of PM on endothelial function. In addition, participants with greater oxidative potential seem to be more susceptible
Neuroplasticity in visual impairments
The visual acuity loss enables the brain to access new pathways in the quest to overcome the visual limitation and this is wellknown as neuroplasticity which have mechanisms to cortical reorganization. In this review, we related the evidences about the neuroplasticity as well as cortical anatomical differences and functional repercussions in visual impairments. We performed a systematic review of PUBMED database, without date or status publication restrictions. The findings demonstrate that the visual impairment produce a compensatory sensorial effect, in which non-visual areas are related to both cross (visual congenital) and multimodal (late blind) neuroplasticity
Influence of ischemic core muscle fibers on surface depolarization potentials in superfused cardiac tissue preparations: a simulation study
Thin-walled cardiac tissue samples superfused with oxygenated solutions are widely used in experimental studies. However, due to decreased oxygen supply and insufficient wash out of waste products in the inner layers of such preparations, electrophysiological functions could be compromised. Although the cascade of events triggered by cutting off perfusion is well known, it remains unclear as to which degree electrophysiological function in viable surface layers is affected by pathological processes occurring in adjacent tissue. Using a 3D numerical bidomain model, we aim to quantify the impact of superfusion-induced heterogeneities occurring in the depth of the tissue on impulse propagation in superficial layers. Simulations demonstrated that both the pattern of activation as well as the distribution of extracellular potentials close to the surface remain essentially unchanged. This was true also for the electrophysiological properties of cells in the surface layer, where most relevant depolarization parameters varied by less than 5.5Ā %. The main observed effect on the surface was related to action potential duration that shortened noticeably by 53Ā % as hypoxia deteriorated. Despite the known limitations of such experimental methods, we conclude that superfusion is adequate for studying impulse propagation and depolarization whereas repolarization studies should consider the influence of pathological processes taking place at the core of tissue sample
A rare differential diagnosis of excessive daytime sleepiness - Artery of Percheron territory infarct
Stroke is an example of neurological diseases that can commonly drives Excessive Daytime Sleepiness (EDS). Extensive strokes with brain edema can leave a brain herniation and coma. Other causes of EDS after stroke are strategic lesions at Thalamus and brainstein. A 56-year-old man, right handed, with hypertension and hypercholesterolemia was admitted at Emergency Room due to 5 days onset of EDS, memory impairment, and left-sided weakness. A brain magnetic resonance imaging showed paramedian thalamic hyperintensity with rostral midbrain hyperintensity extending along the pial surface of the interpeduncular fossa. The artery of Percheron (AP) is an unusual anatomical variation that originates from the posterior cerebral artery and irrigates the paramedian regions of the thalamus and part of the midbrain. It is important the clinical suspicions with detailed drowsy patients history. Awareness of the clinical and neuroimaging features of this stroke syndrome is essential for timely diagnosis and appropriate management
Off-pump bidirectional Glenn through right anterior thoracotomy
AbstractThe Glenn operation involving anastomosis of the superior vena cava to the pulmonary artery has been performed for palliative operations of many cyanotic congenital heart diseases in addition to the single ventricle since the 1960s. The classic procedure is done via median sternotomy and cardiopulmonary bypass. The benefits of this procedure without the use of cardiopulmonary bypass remain mixed within reported series. Cases using this approach and off-pump technique together in Latin-America have not yet been reported in the scientific literature