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81.
82.
The multiscale time irreversibility (MTI) involves the lack of consistency in the properties of a time series if one reverses the reading direction along the time. To analyze the RR time series at rest and during aerobic exercise through the MTI, both in healthy people and cardiac patients. The heartbeat signal was recorded beat to beat for 15 min at rest and 15 min while pedalling on a static bicycle in 10 healthy and active men (age 26.5 ± 3.3 years; height 179.3 ± 6.6 cm; weight 80.4 ± 11.8 kg) and 10 cardiac patients (age 61.1 ± 4.7 years, height 165.3 ± 5.3 cm; weight 86.9 ± 11.1 kg). The MTI was calculated through the asymmetry index (AI), defined as the sum of the values of asymmetry obtained for each scale from 1 to 10. The AI decreases significantly in healthy subjects from 0.51 ± 0.28 at rest to 0.28 ± 0.24 during exercise (P = 0.01) but not in cardiac patients (?0.2204 ± 0.5097 at rest and 0.0848 ± 0.1200 during exercise; P = 0.07). MTI distinguish adequately the four experimental situations because it can be considered as an index of the internal property of the signal in contrast to linear methods which are highly sensitive to external influences over the heart rhythm, particularly sympathetic and parasympathetic stimuli. 相似文献
83.
Pilar A Saiz Maria P Garcia-Portilla Celso Arango Blanca Morales Sara Martinez-Barrondo Victoria Alvarez Eliecer Coto Juan Fernandez Manuel Bousono Julio Bobes 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(6):678-680
The aim of this study is to investigate the association between three polymorphisms of the interleukin-1 (IL-1) gene complex and schizophrenia. We genotyped 228 outpatients with schizophrenia (DSM-IV criteria) and 419 unrelated healthy controls. The following polymorphisms were analyzed: IL-1alpha -889 C/T, IL-1beta +3953 C/T, and IL-1RA (86 bp)n. No significant differences in genotype or in allelic distribution of the Il-1alpha, IL-1beta, and IL-1RA polymorphisms were found. Estimated haplotype frequencies were similar in both groups. Our data do not suggest that genetically determined changes in the IL-1 gene complex confer increased susceptibility for schizophrenia. 相似文献
84.
Li H Romieu I Sienra-Monge JJ Ramirez-Aguilar M Estela Del Rio-Navarro B Kistner EO Gjessing HK Lara-Sanchez Idel C Chiu GY London SJ 《The Journal of allergy and clinical immunology》2006,117(1):119-126
BACKGROUND: A recent microarray study implicated arginase I (ARG1) and arginase II (ARG2) in mouse allergic asthma models and human asthma. OBJECTIVES: To examine the association between genetic variation in ARG1 and ARG2 and childhood asthma and atopy risk. METHODS: We enrolled 433 case-parent triads, consisting of patients with asthma 4 to 17 years old and their biologic parents, from the allergy clinic of a public hospital in Mexico City between 1998 and 2003. Atopy to 24 aeroallergens was determined by skin prick tests. We genotyped 4 single nucleotide polymorphisms (SNPs) of ARG1 and 4 SNPs of ARG2 with minor allele frequencies higher than 10% by using the TaqMan assay (Roche Molecular Systems, Pleasanton, Calif). RESULTS: ARG1 SNPs and haplotypes were not associated with asthma, but all 4 ARG1 SNPs were associated with the number of positive skin tests (P = .007-.018). Carrying 2 copies of minor alleles for either of 2 highly associated ARG2 SNPs was associated with a statistically significant increased relative risk (RR) of asthma (1.5, 95% CI = 1.1-2.1 for arg2s1; RR = 1.6, 95% CI = 1.1-2.3 for arg2s2). The association was slightly stronger among children with a smoking parent (arg2s1 RR = 2.1, 95% CI = 1.2 - 3.9 with a smoking parent; RR = 1.2, 95% CI = 0.8-1.9 without; interaction P = .025). Haplotype analyses reduced the sample size but supported the single SNP results. One ARG2 SNP was related to the number of positive skin tests (P = .027). CONCLUSION: Variation in arginase genes may contribute to asthma and atopy in children. 相似文献
85.
Linda M. Starnes Dan Su Laura M. Pikkupeura Brian T. Weinert Margarida A. Santos Andreas Mund Rebeca Soria Young-Wook Cho Irina Pozdnyakova Martina Kubec H?jfeldt Andrea Vala Wenjing Yang Blanca López-Méndez Ji-Eun Lee Weiqun Peng Joan Yuan Kai Ge Guillermo Montoya André Nussenzweig Chunaram Choudhary Jeremy A. Daniel 《Genes & development》2016,30(2):149-163
86.
Chioza B Osei-Lah A Nashef L Suarez-Merino B Wilkie H Sham P Knight J Asherson P Makoff AJ 《European journal of human genetics : EJHG》2002,10(12):857-864
Idiopathic generalised epilepsy (IGE) is a common form of epilepsy, including several defined and overlapping syndromes, and likely to be due to the combined actions of mutations in several genes. In a recent study we investigated the calcium channel gene CACNA1A for involvement in IGE, unselected for syndrome, by means of association studies using several polymorphisms within the gene. We reported a highly significant case/control association with a silent single nucleotide polymorphism (SNP) in exon 8 that we confirmed by within-family analyses. In this present study we screened the gene for novel SNPs within 25 kb of exon 8, which have enabled us to define the critical region of CACNA1A in predisposing to IGE. Several intronic SNPs were identified and three, within 1.5 kb of exon 8 and in strong linkage disequilibrium with each other and with the original SNP, were significantly associated with IGE (P=0.00029, P=0.0015 and P=0.010). The associations were not limited to an IGE syndrome or other subgroup. Another SNP, 25 kb away, in intron 6 was also significantly associated with IGE (P=0.0057) but is not in linkage disequilibrium with the SNPs around exon 8. Haplotype predictions revealed even more significant associations (3-marker haplotype: P<10(-6)). Logistic regression showed that all the data can be explained by two of the SNPs, which is consistent with two functionally significant variants being responsible for all five associations, although a single variant cannot be excluded. The functionally significant variant(s) are unlikely to be exonic and suggests an effect on expression or alternative splicing. 相似文献
87.
88.
Zamora L Espinet B Salido M Florensa L Woessner S Pedro C Serrtano S Solé F 《Cancer Genetics and Cytogenetics》2002,134(2):165-167
We report a 89-year-old female diagnosed with chronic myelomonocytic leukemia (CMMoL) presenting with a monosomy 15. To our knowledge, this is the second reported case of CMMoL with monosomy 15. On the other hand, monosomy 15 in complex karyotypes is a frequent chromosome aberration in myelodysplastic syndromes, particularly in refractory anemia with excess of blasts. 相似文献
89.
Axonal damage in multiple sclerosis (MS) lesions is associated with failure of fibrinolysis because of the inhibition of the plasminogen activator system. Plasma membrane receptors for tissue plasminogen activator (tPA) and plasminogen concentrate proteolytic activity on the cell surface and provide protection from inhibitors that in turn may locally enhance the fibrinolytic response. Therefore, we have investigated expression of two of these receptors in MS lesions, annexin II tetramer (AIIt) and low-density lipoprotein receptor-related protein (LRP). In acute MS lesions both AIIt and LRP were immunolocalized on macrophages and astrocytes while LRP was additionally found on neuronal cells in cortical gray matter. Western blot analysis confirmed a significant increase in AIIt in MS lesions and in a proportion of normal-appearing white matter samples, with a highly significant correlation between annexin II levels and factors associated with impeded fibrinolysis, such as plasminogen activator inhibitor-1. Immunoblotting analysis of plasmin(ogen) revealed increased levels of lysine-plasminogen in samples expressing high AIIt protein levels. Our results suggest that limited availability of tPA in MS lesions because of formation of tPA-plasminogen activator inhibitor-1 complexes reduces capability of tPA receptors to generate plasmin, which further diminishes fibrinolytic capacity in active MS lesions and possibly leads to axonal damage. 相似文献
90.
Espinet B Solé F Pedro C Garcia M Bellosillo B Salido M Florensa L Camacho FI Baró T Lloreta J Serrano S 《Human pathology》2005,36(11):1232-1237
Mantle cell lymphoma (MCL) is a B-cell neoplasm with a relatively aggressive clinical course. There is a very small subgroup of patients who present with atypical lymphocytes in peripheral blood, with or without lymphocytosis, lymphadenopathy, or splenomegaly, and with an indolent clinical course. They frequently show mutated IgV(H) genes and CD5 negativity. We report an asymptomatic elderly patient who presented with a single submandibular lymphadenopathy. The biopsy showed immunophenotype and t(11;14)(q13;q32) consistent with MCL. The abnormal lymphoid population was also detected in peripheral blood and bone marrow. The patient has remained asymptomatic for 5 years without receiving any therapy. It is uncertain whether these cases represent an early-stage event in the development or an indolent form of MCL. The existence of such asymptomatic patients with an indolent clinical course should induce a strict clinical judgment in terms of therapeutic decisions. 相似文献