619 research outputs found
On the variance of the Least Mean Square squared-error sample curve
Most studies of adaptive algorithm behavior consider performance measures
based on mean values such as the mean-square error. The derived models are
useful for understanding the algorithm behavior under different environments
and can be used for design. Nevertheless, from a practical point of view, the
adaptive filter user has only one realization of the algorithm to obtain the
desired result. This letter derives a model for the variance of the
squared-error sample curve of the least-mean-square (LMS) adaptive algorithm,
so that the achievable cancellation level can be predicted based on the
properties of the steady-state squared error. The derived results provide the
user with useful design guidelines
Degradation of human kininogens with the release of kinin peptides by extracellular proteinases of Candida spp.
The secretion of proteolytic enzymes by pathogenic microorganisms is one of the most successful strategies used by pathogens to colonize and infect the host organism. The extracellular microbial proteinases can seriously deregulate the homeostatic proteolytic cascades of the host, including the kinin-forming system, repeatedly reported to he activated during bacterial infection. The current study assigns a kinin-releasing activity to secreted proteinases of Candida spp. yeasts, the major fungal pathogens of humans. Of several Candida species studied, C. parapsilosis and C. albicans in their invasive filamentous forms are shown to produce proteinases which most effectively degrade proteinaceous kinin precursors, the kininogens. These enzymes, classified as aspartyl proteinases, have the highest kininogen-degrading activity at low pH (approx. 3.5), but the associated production of bradykinin-related peptides from a small fraction of kininogen molecules is optimal at neutral pH (6.5). The peptides effectively interact with cellular B2-type kinin receptors. Moreover, kinin-related peptides capable of interacting with inflammation-induced B1-type receptors are also formed, but with a reversed pH dependence. The presented variability of the potential extracellular kinin production by secreted aspartyl proteinases of Candida spp. is consistent with the known adaptability of these opportunistic pathogens to different niches in the host organism
Comparison of the Effects of Two Types of Stretching Warm Ups for Rehabilitation
This pilot study compares the effects of static therapeutic trunk stretching using an unstable flex chair, a stretching bench and a stretching stick on physical fitness with those of a general Japanese style of static stretching. The participants underwent physical fitness tests. Before and after warming up using a general Japanese style of stretching and trunk treatment stretching. Twenty-three healthy college students (age, 20.7 ± 1.2 years; height, 165.3 ± 7.6 cm; weight, 59.0 ± 9.7 kg; BMI 21.4 ± 2.3) were enrolled in this study. The physical fitness test assesses grip strength, sit-ups, eyes-closed single-leg stance, sit-and-reach flexibility, six-minute walk, and ten-meter obstacle course. The participants performed vertical jump, forward standing flexion measured using the analog flexion meter, thoracolumbar extension, horizontal flexure, deep forward bow. These results suggest that trunk stretching improves flexibility, walking ability, endurance and explosive power more effectively than the general Japanese style of stretching. Three static trunk stretches can improve flexibility, walking ability, endurance and explosive power. Trunk treatment stretching before physical activity might reduce the incidence of injury and improve the physical performance of individuals who participate in exercise, athletes and injured persons undergoing rehabilitation.ArticleBAOJ Medical and nursing.1(1):003(2015)journal articl
Combined effect of regulatory polymorphisms on transcription of UGT1A1 as a cause of Gilbert syndrome
<p>Abstract</p> <p>Background</p> <p>Gilbert syndrome is caused by defects in bilirubin UDP-glucuronosyltransferase (UGT1A1). The most common variation believed to be involved is A(TA)7TAA. Although several polymorphisms have been found to link with A(TA)7TAA, the combined effect of regulatory polymorphisms in the development of Gilbert syndrome remains unclear.</p> <p>Methods</p> <p>In an analysis of 15 patients and 60 normal subjects, we detected 14 polymorphisms and nine haplotypes in the regulatory region. We classified the 4-kbp regulatory region of the patients into: the TATA box including A(TA)7TAA; a phenobarbital responsive enhancer module including c.-3275T>G; and a region including other ten linked polymorphisms. The effect on transcription of these polymorphisms was studied.</p> <p>Results</p> <p>All haplotypes with A(TA)7TAA had c.-3275T>G and additional polymorphisms. In an <it>in-vitro </it>expression study of the 4-kbp regulatory region, A(TA)7TAA alone did not significantly reduce transcription. In contrast, c.-3275T>G reduced transcription to 69% of that of wild type, and the linked polymorphisms reduced transcription to 88% of wild type. Transcription of the typical regulatory region of the patients was 56% of wild type. Co-expression of constitutive androstane receptor (CAR) increased the transcription of wild type by a factor of 4.3. Each polymorphism by itself did not reduce transcription to the level of the patients, however, even in the presence of CAR.</p> <p>Conclusions</p> <p>These results imply that co-operation of A(TA)7TAA, c.-3275T>G and the linked polymorphisms is necessary in causing Gilbert syndrome.</p
Novel scaling behavior of the Ising model on curved surfaces
We demonstrate the nontrivial scaling behavior of Ising models defined on (i)
a donut-shaped surface and (ii) a curved surface with a constant negative
curvature. By performing Monte Carlo simulations, we find that the former model
has two distinct critical temperatures at which both the specific heat
and magnetic susceptibility show sharp peaks.The critical exponents
associated with the two critical temperatures are evaluated by the finite-size
scaling analysis; the result reveals that the values of these exponents vary
depending on the temperature range under consideration. In the case of the
latter model, it is found that static and dynamic critical exponents deviate
from those of the Ising model on a flat plane; this is a direct consequence of
the constant negative curvature of the underlying surface.Comment: 11 pages 5 figure
UGT1A1 sequence variants and bilirubin levels in early postnatal life: a quantitative approach
<p>Abstract</p> <p>Background</p> <p>Fundamental to definitively identifying neonates at risk of developing significant hyperbilirubinemia is a better understanding of the genetic factors associated with early bilirubin rise. Previous genetic studies have focused on the UGT1A1 gene, associating common variation in the coding or promoter regions with qualitative assessments of bilirubin (i.e. significantly elevated or not). These studies have had conflicting results and limited success. We chose to approach the problem by focusing on the quantitative (absolute) change in bilirubin levels early in post-natal life. We apply this approach to the UGT1A1 gene - exploring the contribution of both rare and common variants to early bilirubin changes.</p> <p>Methods</p> <p>We sequenced the exons, PBREM, 5'-, and 3'- regions of the UGT1A1 gene in 80 otherwise healthy term neonates who had repeat bilirubin levels measured within the first five days of life.</p> <p>Results</p> <p>Three novel coding variants were observed, but there was no clear relationship between rare coding variants and bilirubin rise. Adjusted linear regression models fit to evaluate the relationship between changing bilirubin levels and common UGT1A1variants found that among 39 neonates whose bilirubin was resampled within 33 hours, individuals homozygous for the mutant allele of a 3'UTR SNP had significantly smaller changes in bilirubin (P = 0.003) than individuals carrying the wild-type allele.</p> <p>Conclusions</p> <p>Collectively, rare UGT1A1 coding variants do not appear to play a prominent role in determining early bilirubin levels; however common variants in the 3' UTR of UGT1A1 may modulate the early bilirubin rise. A quantitative approach to evaluating early bilirubin kinetics provides a more robust framework in which to better understand the genetics of neonatal hyperbilirubinemia.</p
Upregulation of the cell-cycle regulator RGC-32 in Epstein-Barr virus-immortalized cells
Epstein-Barr virus (EBV) is implicated in the pathogenesis of multiple human tumours of lymphoid and epithelial origin. The virus infects and immortalizes B cells establishing a persistent latent infection characterized by varying patterns of EBV latent gene expression (latency 0, I, II and III). The CDK1 activator, Response Gene to Complement-32 (RGC-32, C13ORF15), is overexpressed in colon, breast and ovarian cancer tissues and we have detected selective high-level RGC-32 protein expression in EBV-immortalized latency III cells. Significantly, we show that overexpression of RGC-32 in B cells is sufficient to disrupt G2 cell-cycle arrest consistent with activation of CDK1, implicating RGC-32 in the EBV transformation process. Surprisingly, RGC-32 mRNA is expressed at high levels in latency I Burkitt's lymphoma (BL) cells and in some EBV-negative BL cell-lines, although RGC-32 protein expression is not detectable. We show that RGC-32 mRNA expression is elevated in latency I cells due to transcriptional activation by high levels of the differentially expressed RUNX1c transcription factor. We found that proteosomal degradation or blocked cytoplasmic export of the RGC-32 message were not responsible for the lack of RGC-32 protein expression in latency I cells. Significantly, analysis of the ribosomal association of the RGC-32 mRNA in latency I and latency III cells revealed that RGC-32 transcripts were associated with multiple ribosomes in both cell-types implicating post-initiation translational repression mechanisms in the block to RGC-32 protein production in latency I cells. In summary, our results are the first to demonstrate RGC-32 protein upregulation in cells transformed by a human tumour virus and to identify post-initiation translational mechanisms as an expression control point for this key cell-cycle regulator
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