174 research outputs found

    The role of septal perforators and "myocardial bridging effect" in atherosclerotic plaque distribution in the coronary artery disease

    Get PDF
    The distribution of atherosclerotic plaque burden in the human coronary arteries is not uniform. Plaques are located mostly in the left anterior descending artery (LAD), then in the right coronary artery (RCA), circumflex branch (LCx) and the left main coronary artery (LM) in a decreasing order of frequency. In the LAD and LCx, plaques tend to cluster within the proximal segment, while in the RCA their distribution is more uniform. Several factors have been involved in this phenomenon, particularly flow patterns in the left and right coronary artery. Nevertheless, it does not explain the difference in lesion frequency between the LAD and the LCx as these are both parts of the left coronary artery. Branching points are considered to be the risk points of atherosclerosis. In the LCx, the number of side branches is lower than in the LAD or RCA and there are no septal perforators with intramuscular courses like in the proximal third of the LAD and the posterior descending artery (PDA). We hypothesized that septal branches generate disturbed flow in the LAD and PDA in a similar fashion to the myocardial bridge (myocardial bridging effect). This coronary architecture determines the non-uniform plaque distribution in coronary arteries and LAD predisposition to plaque formation

    Predominant location of coronary artery atherosclerosis in the left anterior descending artery. The impact of septal perforators and the myocardial bridging effect

    Get PDF
    INTRODUCTION: Coronary artery atherosclerosis presents characteristic patterns of plaque distribution despite systemic exposure to risk factors. We hypothesized that local hemodynamic forces induced by the systolic compression of intramuscular septal perforators could be involved in atherosclerotic processes in the left anterior descending artery (LAD) adjacent to the septal perforators' origin. Therefore we studied the spatial distribution of atherosclerosis in coronary arteries, especially in relation to the septal perforators' origin. MATERIAL AND METHODS: 64-slice computed tomography angiography was performed in 309 consecutive patients (92 male and 217 female) with a mean age of 59.9 years. Spatial plaque distribution in the LAD was analyzed in relation to the septal perforators' origin. Additionally, plaque distribution throughout the coronary artery tree is discussed. RESULTS: The coronary calcium score (CCS) was positive in 164 patients (53.1%). In subjects with a CCS > 0, calcifications were more frequent in the LAD (n = 150, 91.5%) compared with the right coronary artery (RCA) (n = 94, 57.3%), circumflex branch (CX) (n = 76, 46.3%) or the left main stem (n = 42, 25.6%) (p < 0.001). Total CCS was higher in the LAD at 46.1 (IQR: 104.2) and RCA at 34.1 (IQR: 90.7) than in the CX at 16.8 (IQR: 61.3) (p = 0.007). In patients with calcifications restricted to a single vessel (n = 54), the most frequently affected artery was the LAD (n = 42, 77.8%). In patients with lesions limited to the LAD, the plaque was located mostly (n = 37, 88.1%) adjacent to the septal perforators' origin. CONCLUSIONS: We demonstrated that coronary calcifications are most frequently located in the LAD in proximity to the septal branch origin. A possible explanation for this phenomenon could be the dynamic compression of the tunneled septal branches, which may result in disturbed blood flow in the adjacent LAD segment (milking effect)

    Polymorphism of the flap endonuclease 1 gene in keratoconus and Fuchs endothelial corneal dystrophy

    Get PDF
    Oxidative stress is implicated in the pathogenesis of many diseases, including serious ocular diseases, keratoconus (KC) and Fuchs endothelial corneal dystrophy (FECD). Flap endonuclease 1 (FEN1) plays an important role in the repair of oxidative DNA damage in the base excision repair pathway. We determined the association between two single nucleotide polymorphisms (SNPs), c.-441G>A (rs174538) and g.61564299G>T (rs4246215), in the FEN1 gene and the occurrence of KC and FECD. This study involved 279 patients with KC, 225 patients with FECD and 322 control individuals. Polymerase chain reaction (PCR) and length polymorphism restriction fragment analysis (RFLP) were applied. The T/T genotype of the g.61564299G>T polymorphism was associated with an increased occurrence of KC and FECD. There was no association between the c.-441G>A polymorphism and either disease. However, the GG haplotype of both polymorphisms was observed more frequently and the GT haplotype less frequently in the KC group than the control. The AG haplotype was associated with increased FECD occurrence. Our findings suggest that the g.61564299G>T and c.-441G>A polymorphisms in the FEN1 gene may modulate the risk of keratoconus and Fuchs endothelial corneal dystrophy.peer-reviewe

    Educating diabetics

    Get PDF
    Cukrzyca podobnie jak wiele innych chorób jest nieuleczalna. Diabetycy, aby mogli skutecznie kontrolować i panować nad chorobą muszą znać jej tajniki. Dogłębne poznanie choroby pozwoli na przewidywanie reakcji, z jakimi można się spotkać. Nieodzownym elementem w leczeniu cukrzycy typu 1 oprócz insulinoterapii jest sposób żywienia. I właśnie zasadom żywienia w cukrzycy poświęcony jest niniejszy artykuł.Like many other illnesses, diabetes is incurable. In order to have the illness under control in a proper manner, diabetics must know all the details related to it. An in-depth knowledge on the disease allows them to anticipate possible reactions. Apart from insulin therapy, an essential element of the treatment of type 1diabetes is a proper diet. This article is devoted precisely to the way diabetics should select their food

    The monitoring of glycaemia concentration

    Get PDF
    Jedną z najważniejszych rzeczy jakiej muszą nauczyć się diabetycy to kontrola glikemii. Autorzy w artykule omawiają zasady funkcjonowania i posługiwania się glukometrem. Szczegółowiej charakteryzują także urządzenia do pobierania krwi kapilarnej, oraz urządzenia alternatywne służące temu procederowi. Podkreślają także znaczenie oznaczeń stężenie hemoglobiny glikowanej u diabetyków.One of the most crucial things diabetics have to learn is controlling the glycaemia concentration. In this paper, the description of functions and operation of a glucometer is offered. Devices used to draw capillary blood and their substitutes are characterised in greater detail. Moreover, the significance of glycated haemoglobin measures for diabetics

    The self-care of diabetics : the role of a nurse

    Get PDF
    Chorzy na cukrzycę powinni stać się samowystarczalni w zakresie kontroli stężenia glukozy we krwi oraz wstrzyknięć insuliny do tkanki podskórnej. Posiadanie tych umiejętności nie uzależnia ich od innych osób. Stawiają się w komfortowej sytuacji, jaką jest zdolność do samoopieki. Wychodząc naprzeciw tej tezie autorzy omawiają korzystanie ze strzykawki do wstrzyknięć insuliny, charakteryzują obsługę automatycznych wstrzykiwaczy ( PEN-ów). Przedstawiają także nowoczesne rozwiązania techniczne stosowane w leczeniu chorych na cukrzycę insulinozależną.Diabetics should become self-sufficient as far as controlling their glucose level and injecting insulin to the subcutaneous tissue are concerned. Having these skill makes them independent from the help of others. It puts them in a convenient position of being capable of self-care. With the intention of exploring this matter, the authors discuss using the syringe to inject insulin and characterize the use of automatic injectors (pens). They also present modern technological solutions used for treating the insulin-dependent diabetics

    Enhanced near-infrared response of nano- and microstructured silicon/organic hybrid photodetectors

    Get PDF
    Heterojunctions between an organic semiconductor and silicon are an attractive route to extending the response of silicon photodiodes into the near infrared (NIR) range, up to 2000 nm. Silicon-based alternatives are of interest to replace expensive low band-gap materials, like InGaAs, in telecommunications and imaging applications. Herein, we report on the significant enhancement in NIR photodetector performance afforded by nano- and microstructuring of p-doped silicon (p-Si) prior to deposition of a layer of the organic semiconductor Tyrian Purple (TyP). We show how different silicon structuring techniques, namely, electrochemically grown porous Si, metal-assisted chemical etching, and finally micropyramids produced by anisotropic chemical etching (Si μP), are effective in increasing the NIR responsivity of p-Si/TyP heterojunction diodes. In all cases, the structured interfaces were found to give photodiodes with superior characteristics as compared with planar interface devices, providing up to 100-fold improvement in short-circuit photocurrent, corresponding with responsivity values of 1–5  mA/W in the range of 1.3–1.6 μm. Our measurements show this increased performance is neither correlated to optical effects, i.e., light trapping, nor simply to geometric surface area increase by micro- and nanostructuring. We conclude that the performance enhancement afforded by the structured p-Si/organic diodes is caused by a yet unresolved mechanism, possibly related to electric field enhancement near the sharp tips of the structured substrate. The observed responsivity of these devices places them closer to parity with other, well-established, Si-based NIR detection technologies

    Towards illiberal conditioning? New politics of media regulations in Poland (2015–2018)

    Get PDF
    In this article, we examine how media policy changes aid de-democratisation in Poland. Unfolding the logic underpinning the new politics of media regulations, this article argues that media policy paints a nuanced picture of democratic backsliding. Our Foucault-inspired discourse analysis of media policy archive focuses on the rise of illiberal trends at the cross-roads of the Polish hybrid media system, democracy and society. We find these trends display the features of centralisation of power, cultural politics, political partisanship and social polarisations. We explain these notions, using the concepts of “executive aggrandisement” and “politicisation” of public service media sector

    Fortunella margarita Transcriptional Reprogramming Triggered by Xanthomonas citri subsp. citri

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Citrus canker disease caused by the bacterial pathogen <it>Xanthomonas citri </it>subsp. <it>citri (</it>Xcc) <it>has </it>become endemic in areas where high temperature, rain, humidity, and windy conditions provide a favourable environment for the dissemination of the bacterium. Xcc is pathogenic on many commercial citrus varieties but appears to elicit an incompatible reaction on the citrus relative <it>Fortunella margarita </it>Swing (kumquat), in the form of a very distinct delayed necrotic response. We have developed subtractive libraries enriched in sequences expressed in kumquat leaves during both early and late stages of the disease. The isolated differentially expressed transcripts were subsequently sequenced. Our results demonstrate how the use of microarray expression profiling can help assign roles to previously uncharacterized genes and elucidate plant pathogenesis-response related mechanisms. This can be considered to be a case study in a citrus relative where high throughput technologies were utilized to understand defence mechanisms in <it>Fortunella </it>and citrus at the molecular level.</p> <p>Results</p> <p><b>cDNAs from sequenced kumquat libraries (ESTs) made from subtracted RNA populations, healthy vs. infected, were used to make this microarray</b>. Of 2054 selected genes on a customized array, 317 were differentially expressed (P < 0.05) in Xcc challenged kumquat plants compared to mock-inoculated ones. This study identified components of the incompatible interaction such as reactive oxygen species (ROS) and programmed cell death (PCD). Common defence mechanisms and a number of resistance genes were also identified. In addition, there were a considerable number of differentially regulated genes that had no homologues in the databases. This could be an indication of either a specialized set of genes employed by kumquat in response to canker disease or new defence mechanisms in citrus.</p> <p>Conclusion</p> <p>Functional categorization of kumquat Xcc-responsive genes revealed an enhanced defence-related metabolism as well as a number of resistant response-specific genes in the kumquat transcriptome in response to Xcc inoculation. Gene expression profile(s) were analyzed to assemble a comprehensive and inclusive image of the molecular interaction in the kumquat/Xcc system. This was done in order to elucidate molecular mechanisms associated with the development of the hypersensitive response phenotype in kumquat leaves. These data will be used to perform comparisons among citrus species to evaluate means to enhance the host immune responses against bacterial diseases.</p
    corecore