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排序方式: 共有210条查询结果,搜索用时 15 毫秒
1.
CD36 is a fatty acid translocase in striated muscle cells and cardiomyocytes. Some study suggested that alterations in CD36 gene may be associated with coronary artery disease (CAD) risk. The aim of the current study was to compare the frequency of CD36 variants in region encoding lipid-binding domain in Caucasian patients with early-onset CAD, no-CAD adult controls and neonates. The study group comprised 100 patients with early onset CAD. The genetic control groups were 306 infants and 40 no-CAD adults aged over 70 years. Exons 4, 5 and 6 including fragments of flanking introns were studied using the denaturing high-performance liquid chromatography technique and direct sequencing. Changes detected in analyzed fragment of CD36: IVS3-6 T/C (rs3173798), IVS4-10 G/A (rs3211892), C311T (Thr104Ile, not described so far) in exon 5, G550A (Asp184Asn, rs138897347), C572T (Pro191Leu, rs143150225), G573A (Pro191Pro, rs5956) and A591T (Thr197Thr, rs141680676) in exon 6. No significant differences in the CD36 genotype, allele and haplotype frequencies were found between the three groups. Only borderline differences (p = 0.066) were found between early onset CAD patients and newborns in the frequencies of 591T allele (2.00% vs 0.50%) and CGCGCGT haplotype (2.00% vs 0.50%) with both IVS3-6C and 591T variant alleles. In conclusion, CD36 variants: rs3173798, rs3211892, rs138897347, rs5956, rs143150225 rs141680676 and C311T do not seem to be involved in the risk of early-onset CAD in Caucasian population. 相似文献
2.
The association between angiotensin-converting enzyme insertion/deletion (ACE I/D) polymorphism and risk of myocardial infarction (MI) has been extensively studied. However, the results were in controversy. This study aimed to explore the association between ACE I/D polymorphism and risk of MI by using a meta-analysis. We retrieved the following databases to indentify eligible studies: Medline, Embase, ISI, VIP, CBM and Wan Fang database. The latest update was 10th May, 2012. Odds ratio and 95% confidence interval (95% CI) were used to present the strength of the association. A total of 40 case–control studies with 34 993 participants were included. Overall, D allele of ACE I/D polymorphism was significantly associated with an increased risk of MI in genetic comparison models (OR (95% CI): 1.41 (1.22–1.64) for DD vs. II; 1.11 (1.01–1.21) for ID vs. II; 1.23 (1.10–1.37) for D carriers vs. II; 1.28 (1.15–1.43) for DD vs. I carriers and 1.06 (1.02–1.10) for D carriers vs. I carriers). Subgroup analyses, according to ethnicities and countries of participants also indicated that D allele was significantly associated with an increased risk of MI in Asians (especially for Chinese) and Caucasians (especially for English, French, Germans and Italians) (OR (95% CI) of DD vs. ID + II: 2.11 (1.65–2.70) for Asians and 1.15 (1.05–1.27) for Caucasians). In conclusion, this meta-analysis indicated that D allele of ACE I/D polymorphism was a possible risk factor for MI incidence for both Asians and Caucasians. 相似文献
3.
Danalyn R Holmes Melissa Bredow Kathrin Thor Sydney A Pascetta Irina Sementchoukova Kristen R Siegel Cyril Zipfel Jacqueline Monaghan 《Genetics》2021,217(4)
Immune recognition in plants is governed by two major classes of receptors: pattern recognition receptors (PRRs) and nucleotide-binding leucine-rich repeat receptors (NLRs). Located at the cell surface, PRRs bind extracellular ligands originating from microbes (indicative of “non-self”) or damaged plant cells (indicative of “infected-self”), and trigger signaling cascades to protect against infection. Located intracellularly, NLRs sense pathogen-induced physiological changes and trigger localized cell death and systemic resistance. Immune responses are under tight regulation in order to maintain homeostasis and promote plant health. In a forward-genetic screen to identify regulators of PRR-mediated immune signaling, we identified a novel allele of the membrane-attack complex and perforin (MACPF)-motif containing protein CONSTITUTIVE ACTIVE DEFENSE 1 (CAD1) resulting from a missense mutation in a conserved N-terminal cysteine. We show that cad1-5 mutants display deregulated immune signaling and symptoms of autoimmunity dependent on the lipase-like protein ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1), suggesting that CAD1 integrity is monitored by the plant immune system. We further demonstrate that CAD1 localizes to both the cytosol and plasma membrane using confocal microscopy and subcellular fractionation. Our results offer new insights into immune homeostasis and provide tools to further decipher the intriguing role of MACPF proteins in plants. 相似文献
4.
Emilia Anna Kiryk Konrad Kamieniecki Monika Kwacz 《Computer methods in biomechanics and biomedical engineering》2013,16(15):771-779
AbstractThis paper presents the process of designing a new elastic element replacing a membrane in the chamber stapes prosthesis (ChSP). The results of the study are volume displacement characteristics obtained for the prosthesis and physiological stapes. Simulation tests on a 3D CAD model have confirmed that a properly designed ring can stimulate perilymph with the same or greater efficacy as the physiological stapes footplate placed on the elastic annular ligament. The ChSP with a new elastic element creates a good chance of improving hearing in patients suffering from otosclerosis. 相似文献
5.
F. Veglia G. Cighetti M. De Franceschi L. Zingaro L. Boccotti E. Tremoli 《Biomarkers》2013,18(6):562-573
Oxidative stress has been related to various diseases, gender and ageing, and has been measured by various markers. The authors developed a procedure to compute a global oxidative stress index (OXY-SCORE), reflecting both oxidative and antioxidant markers in healthy subjects. Its performance was tested in relation to age and gender and in coronary artery disease (CAD) patients. Eighty-two healthy subjects and 20 CAD patients were enrolled. Plasma free and total malondialdehyde (F- and T-MDA), glutathione disulphide/reduced form ratio (GSSG/GSH) and urine isoprostanes (iPF2α-III) levels were combined as oxidative damage markers (damage score). GSH, α- and γ-tocopherol (TH) levels, and individual antioxidant capacity were combined as antioxidant defence indexes (protection score). The OXY-SCORE was computed by subtracting the protection score from the damage score. Among single parameters, T-MDA and iPF2α-III significantly correlated with age; only GSH and both tocopherols correlated with male gender in healthy subjects. The OXY-SCORE was positively associated with age (p=0.004) and male gender (p=0.03). As expected, the OXY-SCORE was higher in CAD with a very significant p-value (<0.0001), after adjusting for age, gender and smoking. Combining different markers can potentially provide a powerful index in the evaluation of oxidative stress related to age, gender and CAD status. 相似文献
6.
Rangaraj M. Rangayyan Shantanu Banik J.E. Leo Desautels 《Journal of visualized experiments : JoVE》2013,(78)
We demonstrate methods for the detection of architectural distortion in prior mammograms of interval-cancer cases based on analysis of the orientation of breast tissue patterns in mammograms. We hypothesize that architectural distortion modifies the normal orientation of breast tissue patterns in mammographic images before the formation of masses or tumors. In the initial steps of our methods, the oriented structures in a given mammogram are analyzed using Gabor filters and phase portraits to detect node-like sites of radiating or intersecting tissue patterns. Each detected site is then characterized using the node value, fractal dimension, and a measure of angular dispersion specifically designed to represent spiculating patterns associated with architectural distortion.Our methods were tested with a database of 106 prior mammograms of 56 interval-cancer cases and 52 mammograms of 13 normal cases using the features developed for the characterization of architectural distortion, pattern classification via quadratic discriminant analysis, and validation with the leave-one-patient out procedure. According to the results of free-response receiver operating characteristic analysis, our methods have demonstrated the capability to detect architectural distortion in prior mammograms, taken 15 months (on the average) before clinical diagnosis of breast cancer, with a sensitivity of 80% at about five false positives per patient. 相似文献
7.
Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are the major enzymes responsible for alcohol metabolism in humans. Emerging evidences have shown that functional polymorphisms in ADH and ALDH genes might play a critical role in increasing coronary artery disease (CAD) and myocardial infarction (MI) risks; however, individually published studies showed inconclusive results. The aim of this meta-analysis is to evaluate the associations between the genetic polymorphisms of ADH and ALDH genes with susceptibility to CAD and MI. A literature search was conducted on PubMed, Embase, Web of Science and Chinese BioMedical databases from inception through December 1st, 2012. Crude relative risks (RRs) with 95% confidence intervals (CIs) were calculated. Twelve case–control studies were included with a total of 9616 subjects, including 2053 CAD patients, 1436 MI patients, and 6127 healthy controls. Meta-analysis showed that mutant genotypes (GA + AA) of the rs671 polymorphism in the ALDH2 gene were associated with increased risk of both CAD and MI (CAD: RR = 1.20, 95%CI: 1.03–1.40, P = 0.021; MI: RR = 1.32, 95%CI: 1.11–1.57, P = 0.002). However, there were no significant associations of ADH genetic polymorphisms to CAD and MI risks (CAD: RR = 0.92, 95%CI: 0.73–1.15, P = 0.445; MI: RR = 0.93, 95%CI: 0.84–1.03, P = 0.148). In conclusion, this meta-analysis provides strong evidence that ALDH2 rs671 polymorphism may be associated with increased risks of CAD and MI. However, further studies are still needed to accurately determine whether ADH genetic polymorphisms are associated with susceptibility to CAD and MI. 相似文献
8.
Vinay Singh Tanwar Mandeep P. Chand Jitender Kumar Gaurav Garg Sandeep Seth Ganesan Karthikeyan Shantanu Sengupta 《Gene》2013
Vitamin B12 is an essential micronutrient synthesized by microorganisms. Mammals including humans have evolved ways for transport and absorption of this vitamin. Deficiency of vitamin B12 (either due to low intake or polymorphism in genes involved in absorption and intracellular transport of this vitamin) has been associated with various complex diseases. Genome-wide association studies have recently identified several common single nucleotide polymorphisms (SNPs) in fucosyl transferase 2 gene (FUT2) to be associated with levels of vitamin B12—the strongest association was with a non-synonymous SNP rs602662 in this gene. In the present study, we attempted to replicate the association of this SNP (rs602662) in an Indian population since a significant proportion has been reported to have low levels of vitamin B12 in this population. A total of 1146 individuals were genotyped for this SNP using a single base extension method and association with levels of vitamin B12 was assessed in these individuals. Regression analysis was performed to analyze the association considering various confounding factors like for age, sex, diet, hypertension, diabetes mellitus and coronary artery disease status. We found that the SNP rs602662 was significantly associated with the levels of vitamin B12 (p value < 0.0001). We also found that individuals adhering to a vegetarian diet with GG (homozygous major genotype) have significantly lower levels of vitamin B12 in these individuals. Thus, our study reveals that vegetarian diet along with polymorphism in the FUT2 gene may contribute significantly to the high prevalence of vitamin B12 deficiency in India. 相似文献
9.
Xiaofei Lv Yuan Zhang Shaoqi Rao Dongfang Su Dan Feng Min Wang Xinrui Li Dan Li Honghui Guo Xiaoyu Zuo Min Xia Haimei Ouyang Wenhua Ling Jian Qiu 《Gene》2013
Studies focusing on the association of gene methylthioadenosine phosphorylase (MTAP) with the risk of coronary artery disease (CAD) and myocardial infarction (MI) are limited. 相似文献
10.
Published data on the association between the myeloperoxidase (MPO) G-463A polymorphism and coronary artery disease (CAD) are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis on this topic was performed. PubMed, EMBASE and Chinese national knowledge infrastructure were searched for studies regarding the association between the MPO G-463A polymorphism and CAD. A logistic regression analysis was used to estimate the genetic effect and the possible genetic model of action. Summary odds ratios (ORs) with their corresponding 95% confidence intervals (CIs) were calculated. There was strong evidence for an association between the MPO G-463A polymorphism and CAD. The genetic model of action was most likely to be co-dominant. Overall, the data showed that AA and GA genotypes were significantly associated with reduced risk of CAD (AA vs. GG: OR = 0.37, 95% CI = 0.17–0.78; GA vs. GG: OR = 0.73, 95% CI = 0.57–0.92). In subgroup analyses by study population and sources of controls, statistically significant results were observed in the Chinese population (AA vs. GG: OR = 0.21, 95% CI = 0.10–0.43; GA vs. GG: OR = 0.57, 95% CI =0.44–0.74) and in hospital-based control studies (AA vs. GG: OR = 0.20, 95% CI = 0.10–0.39; GA vs. GG: OR = 0.61, 95% CI = 0.48–0.77). This meta-analysis suggests that the MPO G-463A variant genotypes may be associated with decreased risk of CAD. However, given the limited number of studies and the potential biases, the influence of this polymorphism on CAD risk needs further investigation. 相似文献