357 research outputs found
Vernix caseosa as a multi-component defence system based on polypeptides, lipids and their interactions
To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldVernix caseosa is a white cream-like substance that covers the skin of the foetus and the newborn baby. Recently, we discovered antimicrobial peptides/proteins such as LL-37 in vernix, suggesting host defence functions of vernix. In a proteomic approach, we have continued to characterize proteins in vernix and have identified 20 proteins, plus additional variant forms. The novel proteins identified, considered to be involved in host defence, are cystatin A, UGRP-1, and calgranulin A, B and C. These proteins add protective functions to vernix such as antifungal activity, opsonizing capacity, protease inhibition and parasite inactivation. The composition of the lipids in vernix has also been characterized and among these compounds the free fatty acids were found to exhibit antimicrobial activity. Interestingly, the vernix lipids enhance the antimicrobial activity of LL-37 in vitro, indicating interactions between lipids and antimicrobial peptides in vernix. In conclusion, vernix is a balanced cream of compounds involved in host defence, protecting the foetus and newborn against infection
On Planning of FTTH Access Networks with and without Redundancy
Abstract. This paper presents a planning analysis of FTTH access network with and without redundancy. Traditionally, access networks are planned only without redundancy, which is mainly due to lowering the cost of deployment. As fiber optics provide a huge amount of capacity, more and more services are being offered on a single fiber connection. Therefore, as a single point of failure in fiber connection can cause multiple service deprivation, redundancy is very crucial. In this work, an automated planning model was used to test different scenarios of implementation. Cost estimation is presented in terms of digging and amount of fiber used. Three topologies, including the traditional one "tree topology", were tested with a combination of various passive optical technologies
Synthesis and enantiospecific analysis of enantiostructured triacylglycerols containing n-3 polyunsaturated fatty acids
The stereospecific structure of triacylglycerols (TAGs) affects the bioavailability of fatty acids. Lack of enantiopure reference compounds and effective enantiospecific methods have hindered the stereospecific analysis of individual TAGs. Twelve novel enantiostructured AAB-type TAGs were synthesized containing one of the three n-3 polyunsaturated fatty acid: α-linolenic acid (ALA), eicosapentaenoic acid (EPA), or docosahexaenoic acid (DHA) in sn-1 or sn-3 position. These compounds formed six enantiomer pairs, which were separated with recycling high-performance liquid chromatography using chiral columns and UV detection. The chromatographic retention behavior of the enantiomers and the stereospecific elution order were studied. The enantiomer with an n-3 PUFA in the sn-1 position eluted faster than the enantiomer with the n-3 PUFA in the sn-3 position, regardless of the carbon chain length and number of double bonds of the PUFA. TAG enantiomers containing DHA exhibited highly different retention on the chiral column and were separated after the first column, whereas recycling was needed to separate the enantiomer pairs containing ALA or EPA. The system using two identical columns and one mobile phase, without sample derivatization, proved to be very effective also for peak purity assessment, confirming the enantiopurity of the synthesized structured TAGs being higher than 98 % (96 % ee)
Automated Risk Identification of Myocardial Infarction Using Relative Frequency Band Coefficient (RFBC) Features from ECG
Various structural and functional changes associated with ischemic (myocardial infarcted) heart cause amplitude and spectral changes in signals obtained at different leads of ECG. In order to capture these changes, Relative Frequency Band Coefficient (RFBC) features from 12-lead ECG have been proposed and used for automated identification of myocardial infarction risk. RFBC features reduces the effect of subject variabilty in body composition on the amplitude dependent features. The proposed method is evaluated on ECG data from PTB diagnostic database using support vector machine as classifier. The promising result suggests that the proposed RFBC features may be used in the screening and clinical decision support system for myocardial infarction
The effect of spiritual healing on in vitro tumour cell proliferation and viability – an experimental study
Alternative treatments such as spiritual healing and prayer are increasingly popular, especially among patients with life-threatening diseases such as cancer. According to theories of spiritual healing, this intervention is thought to influence living cells and organisms independently of the recipient's conscious awareness of the healer's intention. The aim of this study was to test the hypothesis that spiritual healing will reduce proliferation and viability of two cancer cell lines in vitro. Three controlled experiments were conducted with three different healers and randomised allocation of cells to five different doses of healing or control. Researchers conducting the assays and statistical analyses were blinded to the experimental conditions. Main outcome measures were MTT viability, 3H-thymidine incorporation and counts of an adherent human breast cancer cell line (MCF-7), and a nonadherent mouse B-lymphoid cell line (HB-94). Analyses of variance (ANOVAs) revealed no significant main or dose-related effects of spiritual healing compared to controls for either of the two cell lines or any of the assays (P-values between 0.09 and 0.96). When comparing healing and control across all three experimental days, doses, assays, and cells, 34 (51.6%) of 66 independent comparisons showed differences in the hypothesised direction (P=0.90). The average effect size across cell lines, days, assays, and doses approached zero (Cohen's d=−0.01). The results do not support previous reports of beneficial effects of spiritual healing on malignant cell growth in vitro. Reported beneficial effects of spiritual healing on the well-being of cancer patients seem more likely to be mediated by psychosocial and psychophysiological effects of the healer–patient relationship
Role of the podocyte in proteinuria
In recent years, the podocyte, with its elaborate cytoarchitecture and slit diaphragm, has been the focus of extensive research, yet its precise role in the glomerular filtration barrier is still debated. There are puzzling observations indicating that a comprehensive mechanistic model for glomerular filtration is still necessary. There is no doubt that podocytes are essential for glomerular filtration barrier integrity. However, most albumin never reaches the podocyte because it is prevented from entering the glomerular filter at the endothelium level. Another puzzling observation is that the glomerular filter never clogs despite its high load of several kilograms of plasma proteins per day. Recently, we proposed a novel model in which an electrical potential difference is generated across the glomerular filtration barrier by filtration. The model offers novel potential solutions to some of the riddles regarding the glomerular filter
Role of Glomerular Proteoglycans in IgA Nephropathy
Mesangial matrix expansion is a prominent feature of the most common form of glomerulonephritis, IgA nephropathy (IgAN). To find molecular markers and improve the understanding of the disease, the gene and protein expression of proteoglycans were investigated in biopsies from IgAN patients and correlated to clinical and morphological data. We collected and microdissected renal biopsies from IgAN patients (n = 19) and from healthy kidney donors (n = 14). Patients were followed for an average time of 4 years and blood pressure was according to target guidelines. Distinct patterns of gene expression were seen in glomerular and tubulo-interstitial cells. Three of the proteoglycans investigated were found to be of special interest and upregulated in glomeruli: perlecan, decorin and biglycan. Perlecan gene expression negatively correlated to albumin excretion and progress of the disease. Abundant decorin protein expression was found in sclerotic glomeruli, but not in unaffected glomeruli from IgAN patients or in controls. Transforming growth factor beta (TGF-β), known to interact with perlecan, decorin and biglycan, were upregulated both on gene and protein level in the glomeruli. This study provides further insight into the molecular mechanisms involved in mesangial matrix expansion in IgAN. We conclude that perlecan is a possible prognostic marker for patients with IgAN. In addition, the up-regulation of biglycan and decorin, as well as TGF-β itself, indicate that regulation of TGF-β, and other profibrotic markers plays a role in IgAN pathology
Is the Presence of Microalbuminuria a Relevant Marker of Kidney Disease?
Levels of urinary albumin excretion that are below the usual limit of detection by qualitative testing, but are above normal levels (microalbuminuria; MA), can be readily identified by simple measures, such as the urinary albumin to creatinine ratio in untimed urine samples. Such measurements, particularly when combined with assessment of estimated glomerular filtration rate (eGFR), have utility as biomarkers for enhanced risk of all-cause mortality, cardiovascular events, progressive chronic kidney disease, and end-stage renal disease in diabetic and nondiabetic subjects. However, it is controversial whether “isolated” MA (MA in the absence of a clear reduction in eGFR, urine sediment abnormalities, or structural renal disease) should be regarded as kidney disease. Such MA could also be regarded as a manifestation of a diffuse endothelial (microvascular) injury and thereby collateral kidney damage. This article reviews the current evidence concerning MA as a marker of kidney disease or kidney damage
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