508 research outputs found
ABCB1-C3435T polymorphism and breast cancer risk: A case-control study and a meta-analysis
Purpose: To investigate the association of ABCB1-C3435T transition with breast cancer risk which was followed by a meta-analysis. Methods: In a case-control study we collected blood samples from 290 women (including 150 breast cancer patients and 140 healthy controls). ABCB1-C3435T genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. A meta-analysis was performed for a total of 13 eligible studies involving 5,835 cases and 8,178 controls. Results: The results of case-control study revealed a significant association between T allele (OR=1.770, 95%CI=1.236-2.535, p=0.002), CT genotype (OR=1.661, 95%CI=1.017-2.713, p=0.042), and TT genotype (OR=3.399, 95%C1=1.409-8.197, p=0.006) with breast cancer risk. Data from meta-analysis revealed a significant association between ABCB1-C3435T polymorphism and breast cancer risk in allelic (OR=1.243, 95%CI=1.079-1.432, p=0.003), co-dominant (OR=1.349, 95%CI=1.042-1.746, p=0.023), dominant (OR=1.204, 95%CI=1.019-1.422, p=0.029), and recessive (OR=1.226, 9S%C1-1.0U-1.488, p=0.039) models. Conclusions: The results suggest that the ABCB1-C3435T gene polymorphism might be a genetic risk factor and a potential biomarker for breast cancer
Perfectionism Search Algorithm (PSA): An Efficient Meta-Heuristic Optimization Approach
This paper proposes a novel population-based meta-heuristic optimization
algorithm, called Perfectionism Search Algorithm (PSA), which is based on the
psychological aspects of perfectionism. The PSA algorithm takes inspiration
from one of the most popular model of perfectionism, which was proposed by
Hewitt and Flett. During each iteration of the PSA algorithm, new solutions are
generated by mimicking different types and aspects of perfectionistic behavior.
In order to have a complete perspective on the performance of PSA, the proposed
algorithm is tested with various nonlinear optimization problems, through
selection of 35 benchmark functions from the literature. The generated
solutions for these problems, were also compared with 11 well-known
meta-heuristics which had been applied to many complex and practical
engineering optimization problems. The obtained results confirm the high
performance of the proposed algorithm in comparison to the other well-known
algorithms
Is corneal sensitivity sex dependent?
Purpose: To determine whether corneal sensitivity is different between the two genders. Methods: Corneal sensitivity of 130 normal volunteers, including 77 women and 53 men aged 20-35 years, with no history of previous ocular surgery was measured using the Cochet-Bonnet esthesiometer. Measurements were done on five corneal regions: central, nasal, inferior, temporal and superior. The findings were compared between men and women using the non-parametric Mann-Whitney U test. Results: Mean age of male subjects was 28.0 years and that of female participants was 26.8 years (P = 0.063). There was a significant difference in corneal sensitivity between men and women in the superior (P = 0.013), temporal (P = 0.020) and inferior (P = 0.046) regions. There was no significant difference in corneal sensitivity in the central (P = 0.862) and nasal (P = 0.273) regions. Conclusion: Except for the central and nasal regions, corneal sensitivity is significantly higher in men as compared to women. The reason for this difference is not yet evident. © 2015 Journal of Ophthalmic and Vision Research
Survivin c.-31G>C (rs9904341) gene transversion and urinary system cancers risk: A systematic review and a meta-analysis
Aim: To investigate the possible association between survivin c.-31G>C (rs9904341) gene polymorphism and urinary system cancers by a meta-analysis approach. Methods: Standard electronic literature databases were searched to find eligible studies. The odds ratios (ORs) with 95 CIs were estimated to find the associations possibility. Results: Overall meta-analysis revealed significant associations between c.-31G>C transversion and risk of urinary tract cancers in dominant (OR: 1.34; 95 CI: 1.02-1.75; p = 0.035), recessive (OR: 1.52; 95 CI: 1.33-1.74; p C transversion might be a risk factor for urinary system cancers. However, more articles with different ethnicities will help to obtain a more accurate conclusion. © 2018 Future Medicine Ltd
Motion correction of SPEC projection before reconstruction
In Single Photon Emission Computed Tomography (SPECT), the data acquisition occurs over a relatively long
time, typically in the range of 5-30 minutes. During this period, the patient must lie still to guarantee the image
quality. Nevertheless, patient movement has frequently been reported in clinical applications. This movement
causes misalignment of the projection frames, which degrades the reconstructed image and may introduce
artifacts. However, the ability to detect and correct for the motion using a computational method is valuable for
quality assurance of SPECT imaging.
In this work a correlation function based on Linogram and Sinogram of the projection is evaluated in order to
estimate the occurred motion and correct it for the best alignment.
By our implemented method the motion artifacts of our cases reduced considerably and our results showed that
the misalignment (motion) between the projections could be found with a small error depending on the
resolution of the images (pixel size), and the time and duration of the applied motion during the course of
projection acquisition
Il-1� C376a transversion variant and risk of idiopathic male infertility in Iranian men: A genetic association study
Background: IL-1α produced by Sertoli cells is considered to act as a growth factor for spermatogonia. In this study,
we investigated the association of the C376A polymorphism in IL-1α with male infertility in men referring to the Kashan IVF Center.
Materials and Methods: In this case-control study, 2 ml of blood was collected from 230 fertile and 230 infertile men. After DNA extraction, the C376A variant was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In addition, the molecular effects of the C376A transversion were analysed using bioinformatics tools.
Results: A significant association was observed between the homozygous genotype CC with male infertility [odds ratio
(OR)=1.97, 95% confidence interval (CI)=1.14-3.41, P=0.016)]. Carriers of C (AC+CC) showed a similar risk for
male infertility (OR=1.78, 95% CI=1.06-2.99, P=0.030). Also, allelic analysis showed that the C allele is associated
with male infertility (OR=1.43, 95% CI=1.09-1.88, P=0.011). In sub-group analysis, we found that the AC genotype
is associated with asthenozoospermia (OR=2.38, 95% CI=1.03-5.53, P=0.043). In addition, carriers of C were at
high risk for asthenozoospermia (OR=2.25, 95% CI=1.01-4.10, P=0.047). Also, C allele was significantly associated
with oligozoospermia (OR=1.44, 95% CI=1.01-2.06, P=0.049) and non-obstructive azoospermia (OR=1.67, 95% CI
=1.04-2.68, P=0.034). Finally, in silico analysis showed that the C376A polymorphism could alter splicing especially
in the acceptor site.
Conclusion: This is the preliminary report on the association of IL-1α C376A polymorphism with male infertility in the
Kashan population. This association shows that the IL-1α gene may be a biomarker for male infertility, and therefore
needs additional investigations in future studies to validate this.
Keywords: Genetic Polymorphism, Interleukin-1α, Male Infertility, Spermatogenesi
Detection and evaluation of damage in aircraft composites using electromagnetically coupled inductors
The paper presents a quantitative damage evaluation of carbon-fibre reinforced polymer (CFRP) plates using a non-contact electromagnetic (EM) sensor. The EM sensor with coupled spiral inductors (CSI) is employed here to detect both impact induced and simulated damage leading to an accurate evaluation of the location, depth and width of sub-surface defects. The effect of inspection frequency, standoff distance and signal power are also investigated leading to the development of an engineering circuit design tool that relates the set up and calibration of the sensor to its detection performance. It is found that the dynamic range of the transmission coefficient is the limiting factor in the original Salski CSI sensor and this problem is addressed by adding ferrite layers to reduce the reluctance of the magnetic circuit, improving damage sensing by 22%. The study leads to a further development of utilising an open ferrite yoke with a pair of encircling coils, which shows a 57% sensitivity improvement and clearer identification of air gaps (voids) and delamination in CFRP laminates. The proposed EM yoke design CSI sensor is low cost and could be assembled into an array for non-contact, in situ mechatronic scanning of aircraft composite wings
Association analysis of rs1049255 and rs4673 transitions in p22phox gene with coronary artery disease: A case-control study and a computational analysis
Background
The p22phox gene encodes the main subunit of NADH/NADPH-oxidase. This enzyme is expressed in smooth muscle cells of arteries, and it produces the reactive oxygen species. On the other hand, oxidative stress plays a main role in the pathogenesis of coronary artery disease (CAD).
Aim
The aim of this study is to evaluate the association between rs4673 and rs1049255 polymorphisms of p22phox gene with CAD in an Iranian population which was followed with a computational analysis approach.
Methods
In a cross-sectional study, we collected blood samples of 302 Iranian Caucasian including 143 patients and 159 healthy controls. Genotype of the polymorphisms was detected through PCR-RFLP method. A computational analysis was also performed using SNAP, Polyphen-2, Chou-Fasman, RNAsnp, and miRNA SNP databases.
Results
Data of case control study demonstrated that CT genotype (R = 1.84, 95% CI = 1.13–3.00, p = 0.014) and T allele (OR = 1.53, 95% CI = 1.09–2.15, p = 0.013) of rs4673 polymorphism, have a significant association with enhanced risk of CAD. But rs1049255 analysis demonstrated the absence of such an association with CAD. Indeed, in silico data analysis demonstrated that rs4673 transition could impact on function of p22phox protein (SNAP score 56, expected accuracy 75%; Polyphen-2 score 0.99, sensitivity 0.09, specificity 0.99). Data derived from miRNA SNP database demonstrated that rs1049255 polymorphism increases the affinity of attachment between has-miR-3689a-3b with 3′-UTR of p22phox gene.
Conclusion
Our data demonstrated that rs4673 transition may be involved in susceptibility to CAD and could be applied as a potential biomarker for this disease
Shearfree perfect fluids with solenoidal magnetic curvature and a gamma-law equation of state
We show that shearfree perfect fluids obeying an equation of state p=(gamma
-1) mu are non-rotating or non-expanding under the assumption that the spatial
divergence of the magnetic part of the Weyl tensor is zero.Comment: 11 page
Effects of Synaptic and Myelin Plasticity on Learning in a Network of Kuramoto Phase Oscillators
Models of learning typically focus on synaptic plasticity. However, learning
is the result of both synaptic and myelin plasticity. Specifically, synaptic
changes often co-occur and interact with myelin changes, leading to complex
dynamic interactions between these processes. Here, we investigate the
implications of these interactions for the coupling behavior of a system of
Kuramoto oscillators. To that end, we construct a fully connected,
one-dimensional ring network of phase oscillators whose coupling strength
(reflecting synaptic strength) as well as conduction velocity (reflecting
myelination) are each regulated by a Hebbian learning rule. We evaluate the
behavior of the system in terms of structural (pairwise connection strength and
conduction velocity) and functional connectivity (local and global
synchronization behavior). We find that for conditions in which a system
limited to synaptic plasticity develops two distinct clusters both structurally
and functionally, additional adaptive myelination allows for functional
communication across these structural clusters. Hence, dynamic conduction
velocity permits the functional integration of structurally segregated
clusters. Our results confirm that network states following learning may be
different when myelin plasticity is considered in addition to synaptic
plasticity, pointing towards the relevance of integrating both factors in
computational models of learning.Comment: 39 pages, 15 figures This work is submitted in Chaos: An
Interdisciplinary Journal of Nonlinear Scienc
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