997 resultados para SUBSET


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The phenotypic and genetic factor structure of performance on five Multidimensional Aptitude Battery (MAB) subtests and one Wechsler Adult Intelligence Scale-Revised (WAIS-R) subtest was explored in 390 adolescent twin pairs (184 monozygotic [MZ]; 206 dizygotic (DZ)). The temporal stability of these measures was derived from a subsample of 49 twin pairs, with test-retest correlations ranging from .67 to .85. A phenotypic factor model, in which performance and verbal factors were correlated, provided a good fit to the data. Genetic modeling was based on the phenotypic factor structure, but also took into account the additive genetic (A), common environmental (C), and unique environmental (E) parameters derived from a fully saturated ACE model. The best fitting model was characterized by a genetic correlated two-factor structure with specific effects, a general common environmental factor, and overlapping unique environmental effects. Results are compared to multivariate genetic models reported in children and adults, with the most notable difference being the growing importance of common genes influencing diverse abilities in adolescence. (C) 2003 Elsevier Inc. All rights reserved.

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Purpose: This study investigated leukocyte subset responses to moderate-intensity exercise under heat stress, with water (W) or carbohydrate (CHO) drink ingestion. Methods: In repeated trials, 13 soldiers consumed either a W or CHO drink during 3 h of walking at 4.4 km center dot h(-1) with a 5% gradient (15 min rest per hour) under heat stress (35 C and 55% relative humidity). The soldiers wore combat uniforms and carried water bottles and dummy rifles and ammunition, altogether weighing about 11.5 +/- 1.0 kg. Results: Plasma glucose concentration was significantly higher with CHO than W ingestion during exercise (p < 0.01). There were no significant differences between W and CHO conditions in exercise performance, plasma cortisol concentration, heart rate, or core temperature. CHO ingestion significantly moderated the increases in leukocyte (83% in W, 28% in CHO; p < 0.001), monocyte (60% in W, 34% in CHO; p < 0.05), and granulocyte counts (120% in W, 30% in CHO; p < 0.001), but not in lymphocyte count (41% in W, 25% in CHO). Conclusions: The increases in leukocyte and subset counts during moderate-intensity exercise under heat stress may be comparable to those observed during intense exercise in cool conditions. The response of immune cell counts is blunted by CHO intake during moderate-intensity exercise in the heat, and may not occur through the cortisol pathway.

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In this paper we develop an evolutionary kernel-based time update algorithm to recursively estimate subset discrete lag models (including fullorder models) with a forgetting factor and a constant term, using the exactwindowed case. The algorithm applies to causality detection when the true relationship occurs with a continuous or a random delay. We then demonstrate the use of the proposed evolutionary algorithm to study the monthly mutual fund data, which come from the 'CRSP Survivor-bias free US Mutual Fund Database'. The results show that the NAV is an influential player on the international stage of global bond and stock markets.

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Aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) has been used to describe the histological lesion associated with metal-on-metal (M-M) bearings. We tested the hypothesis that the lymphoid aggregates, associated with ALVAL lesions resemble tertiary lymphoid organs (TLOs). Histopathological changes were examined in the periprosthetic tissue of 62 M-M hip replacements requiring revision surgery, with particular emphasis on the characteristics and pattern of the lymphocytic infiltrate. Immunofluorescence and immunohistochemistry were used to study the classical features of TLOs in cases where large organized lymphoid follicles were present. Synchrotron X-ray fluorescence (XRF) measurements were undertaken to detect localisation of implant derived ions/particles within the samples. Based on type of lymphocytic infiltrates, three different categories were recognised; diffuse aggregates (51%), T cell aggregates (20%), and organised lymphoid aggregates (29%). Further investigation of tissues with organised lymphoid aggregates showed that these tissues recapitulate many of the features of TLOs with T cells and B cells organised into discrete areas, the presence of follicular dendritic cells, acquisition of high endothelial venule like phenotype by blood vessels, expression of lymphoid chemokines and the presence of plasma cells. Co-localisation of implant-derived metals with lymphoid aggregates was observed. These findings suggest that in addition to the well described general foreign body reaction mediated by macrophages and a T cell mediated type IV hypersensitivity response, an under-recognized immunological reaction to metal wear debris involving B cells and the formation of tertiary lymphoid organs occurs in a distinct subset of patients with M-M implants. © 2013 Mittal et al.

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* The research is supported partly by INTAS: 04-77-7173 project, http://www.intas.be

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Composition problem is considered for partition constrained vertex subsets of n dimensional unit cube E^n . Generating numerical characteristics of E^n subsets partitions is considered by means of the same characteristics in 1 − n dimensional unit cube, and construction of corresponding subsets is given for a special particular case. Using pairs of lower layer characteristic vectors for E^(1-n) more characteristic vectors for E^n are composed which are boundary from one side, and which take part in practical recognition of validness of a given candidate vector of partitions.

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Владимир Тодоров, Петър Стоев - Тази бележка съдържа елементарна конструкция на множество с указаните в заглавието свойства. Да отбележим в допълнение, че така полученото множество остава напълно несвързано дори и след като се допълни с краен брой елементи.

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Background: Monocytes are implicated in the initiation and progression of theatherosclerotic plaque contributing to plaque instability and rupture. Little is knownof the role played by the 3 phenotypically and functionally different monocytesubpopulations in determining ventricular remodeling following ST elevation my-ocardial infarction (STEMI). Mon1 are "classical" inflammatory monocytes, whilstMon3 are considered reparative with fibroblast deposition ability. The function ofthe newly described Mon2 is yet to be elucidated. Method: STEMI patients (n=196, mean age 62±13 years; 72% male) treatedwith percutaneous revascularization were recruited within the first 24 hours. Pe-ripheral blood monocyte subpopulations were enumerated and characterizedusing flow cytometry after staining for CD14, CD16 and CCR2. Phenotypi-cally, monocyte subpopulations are defined as: CD14+CD16-CCR2+ (Mon1),CD14+CD16+CCR+ (Mon2) and CD14lowCD16+CCR2- (Mon3) cells. Transtho-racic 2D echocardiography was performed within 7 days and 6 months post infarctto assess ventricular volumes, mass, systolic, and diastolic functions. Results: Using linear regression analysis higher counts for Mon1, and lowercounts for Mon2 and Mon3 were significantly associated with the baseline leftventricular ejection fraction (LVEF) within seven days post infarction. At 6 monthspost STEMI lower counts of Mon2 remained positively associated with decreasedLVEF (p value= 0.002).Monocyte subsets correlation with LVEFMonocytes mean florescence Baseline left ventricular Left ventricular ejectionintensity (cells/μl) ejection fraction (%) fraction (%) at 6 months post infarctβ-value P-valueβ-value P-valueTotal Mon0.31 P<0.001 0.360.009Mon 10.019 0.020.070.62Mon 2−0.28 0.001 −0.420.002Mon 3−0.27 0.001 −0.180.21 Conclusion: Peripheral monocytes of all three subsets correlate with LVEF af-ter a myocardial infarction. High counts of the inflammatory Mon1 are associatedwith reduction in the baseline LVEF. Post remodelling, the convalescent EF wasindependently predicted by monocyte subpopulation 2. As lower counts depictednegative ventricular remodeling, this suggests a reparative role for the newly de-scribed Mon2, possibly via myofibroblast deposition and angiogenesis, in contrastto an anticipated inflammatory role.

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High-grade Brainstem Glioma (BSG), also known as Diffuse Intrinsic Pontine Glioma (DIPG), is an incurable pediatric brain cancer. Increasing evidence supports the existence of regional differences in gliomagenesis such that BSG is considered a distinct disease from glioma of the cerebral cortex (CG). In an effort to elucidate unique characteristics of BSG, we conducted expression analysis of mouse PDGF-B-driven BSG and CG initiated in Nestin progenitor cells and identified a short list of expression changes specific to the brainstem gliomagenesis process, including abnormal upregulation of paired box 3 (Pax3). In the neonatal mouse brain, Pax3 expression marks a subset of brainstem progenitor cells, while it is absent from the cerebral cortex, mirroring its regional expression in glioma. Ectopic expression of Pax3 in normal brainstem progenitors in vitro shows that Pax3 inhibits apoptosis. Pax3-induced inhibition of apoptosis is p53-dependent, however, and in the absence of p53, Pax3 promotes proliferation of brainstem progenitors. In vivo, Pax3 enhances PDGF-B-driven gliomagenesis by shortening tumor latency and increasing tumor penetrance and grade, in a region-specific manner, while loss of Pax3 function extends survival of PDGF-B-driven;p53-deficient BSG-bearing mice by 33%. Importantly, Pax3 is regionally expressed in human glioma as well, with high PAX3 mRNA characterizing 40% of human BSG, revealing a subset of tumors that significantly associates with PDGFRA alterations, amplifications of cell cycle regulatory genes, and is exclusive of ACVR1 mutations. Collectively, these data suggest that regional Pax3 expression not only marks a novel subset of BSG but also contributes to PDGF-B-induced brainstem gliomagenesis.

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The mechanisms responsible for increased cardiovascular risk associated with HIV-1 infection are incompletely defined. Using flow cytometry, in the present study, we examined activation phenotypes of monocyte subpopulations in patients with HIV-1 infection or acute coronary syndrome to find common cellular profiles. Nonclassic (CD14(+)CD16(++)) and intermediate (CD14(++)CD16(+)) monocytes are proportionally increased and express high levels of tissue factor and CD62P in HIV-1 infection. These proportions are related to viremia, T-cell activation, and plasma levels of IL-6. In vitro exposure of whole blood samples from uninfected control donors to lipopolysaccharide increased surface tissue factor expression on all monocyte subsets, but exposure to HIV-1 resulted in activation only of nonclassic monocytes. Remarkably, the profile of monocyte activation in uncontrolled HIV-1 disease mirrors that of acute coronary syndrome in uninfected persons. Therefore, drivers of immune activation and inflammation in HIV-1 disease may alter monocyte subpopulations and activation phenotype, contributing to a pro-atherothrombotic state that may drive cardiovascular risk in HIV-1 infection.

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Translocations in myeloma are thought to occur solely in mature B cells in the germinal center through class switch recombination (CSR). We used a targeted captured technique followed by massively parallel sequencing to determine the exact breakpoints in both the immunoglobulin heavy chain (IGH) locus and the partner chromosome in 61 presentation multiple myeloma samples. The majority of samples (62%) have a breakpoint within the switch regions upstream of the IGH constant genes and are generated through CSR in a mature B cell. However, the proportion of CSR translocations is not consistent between cytogenetic subgroups. We find that 100% of t(4;14) are CSR-mediated; however, 21% of t(11;14) and 25% of t(14;20) are generated through DH-JH recombination activation gene-mediated mechanisms, indicating they occur earlier in B-cell development at the pro-B-cell stage in the bone marrow. These 2 groups also generate translocations through receptor revision, as determined by the breakpoints and mutation status of the segments used in 10% and 50% of t(11;14) and t(14;20) samples, respectively. The study indicates that in a significant number of cases the translocation-based etiological events underlying myeloma may arise at the pro-B-cell hematological progenitor cell level, much earlier in B-cell development than was previously thought.

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Bis-(3´-5´)-cyclic dimeric guanosine monophosphate, or cyclic di-GMP (c-di-GMP) is a ubiquitous bacterial second messenger that regulates processes such biofilm formation, motility, and virulence. C-di-GMP is synthesized by diguanylate cyclases (DGCs), while phosphodiesterases (PDE-As) end signaling by linearizing c-di-GMP to 5ʹ-phosphoguanylyl-(3ʹ,5ʹ)-guanosine (pGpG), which is then hydrolyzed to two GMPs by previously unidentified enzymes termed PDE-Bs. To identify the PDE-B responsible for pGpG turnover, a screen for pGpG binding proteins in a Vibrio cholerae open reading frame library was conducted to identify potential pGpG binding proteins. This screen led to identification of oligoribonuclease (Orn). Purified Orn binds to pGpG and can cleave pGpG to GMP in vitro. A deletion mutant of orn in Pseudomonas aeruginosa was highly defective in pGpG turnover and accumulated pGpG. Deletion of orn also resulted in accumulation c-di-GMP, likely through pGpG-mediated inhibition of the PDE-As, causing an increase in c-di-GMP-governed auto-aggregation and biofilm. Thus, we found that Orn serves as the primary PDE-B enzyme in P. aeruginosa that removes pGpG, which is necessary to complete the final step in the c-di-GMP degradation pathway. However, not all bacteria that utilize c-di-GMP signaling also have an ortholog of orn, suggesting that other PDE-Bs must be present. Therefore, we asked whether RNases that cleave small oligoribonucleotides in other species could also act as PDE-Bs. NrnA, NrnB, and NrnC can rapidly degrade pGpG to GMP. Furthermore, they can reduce the elevated aggregation and biofilm formation in P. aeruginosa ∆orn. Together, these results indicate that rather than having a single dedicated PDE-B, different bacteria utilize distinct RNases to cleave pGpG and complete c-di-GMP signaling. The ∆orn strain also has a growth defect, indicating changes in other regulatory processes that could be due to pGpG accumulation, c-di-GMP accumulation, or another effect due to loss of Orn. We sought to investigate the genetic pathways responsible for these growth defect phenotypes by use of a transposon suppressor screen, and also investigated transcriptional changes using RNA-Seq. This work identifies that c-di-GMP degradation intersects with RNA degradation at the point of the Orn and the functionally related RNases.

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The effectiveness of higher-order spectral (HOS) phase features in speaker recognition is investigated by comparison with Mel Cepstral features on the same speech data. HOS phase features retain phase information from the Fourier spectrum unlikeMel–frequency Cepstral coefficients (MFCC). Gaussian mixture models are constructed from Mel– Cepstral features and HOS features, respectively, for the same data from various speakers in the Switchboard telephone Speech Corpus. Feature clusters, model parameters and classification performance are analyzed. HOS phase features on their own provide a correct identification rate of about 97% on the chosen subset of the corpus. This is the same level of accuracy as provided by MFCCs. Cluster plots and model parameters are compared to show that HOS phase features can provide complementary information to better discriminate between speakers.