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991.
Among the 1700 mutations reported in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, a missense mutation, p.Ser1235Arg, is a relatively frequent finding. To clarify its clinical significance, we collected data from 104 subjects heterozygous for the mutation p.Ser1235Arg from the French CF network, addressed for various indications including classical CF, atypical phenotypes or carrier screening in subjects with or without a family history. Among them, 26 patients (5 having CF, 10 CBAVD (congenital bilateral absence of the vas deferens) and 11 with CF-like symptoms) and 14 healthy subjects were compound heterozygous for a second CFTR mutation. An exhaustive CFTR gene analysis identified a second mutation in cis of p.Ser1235Arg in all CF patients and in 81.8% CBAVD patients. Moreover, epidemiological data from >2100 individuals found a higher frequency of p.Ser1235Arg in the general population than in CF or CBAVD patients. These data, added to the fact that in silico analysis and functional assays suggest a benign nature of this substitution, give several lines of evidence against an association of p.Ser1235Arg with CF or CBAVD.  相似文献   
992.
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994.
A rarely challenged dogma in cell-mediated immune (CMI) assays is the incubation temperature, 37°C. Fever augments proinflammatory immune responses in vivo, and the aim of this study was to explore whether incubation at fever-range temperature could increase antigen-specific biomarker responses. We compared CMI responses following incubation of whole blood at 37°C and 39°C. Whole blood was obtained from (i) 34 healthy subjects whose blood was incubated with TB10.4 antigen, present in the Mycobacterium bovis bacillus Calmette-Guérin vaccine and many environmental mycobacteria; (ii) 8 TB patients and 8 controls incubated with Mycobacterium tuberculosis-specific antigens in the QuantiFERON-TB Gold test (QFT-IT); and (iii) from both groups incubated with a T cell mitogen. T cell responses (gamma interferon [IFN-γ]) and responses from antigen-presenting cells (IFN-γ-induced protein 10 [IP-10]) were determined. We further evaluated the effect of adding interleukin-7 (IL-7) and blocking IL-10 during incubation. In TB patients, IFN-γ and IP-10 levels were increased 4.1- and 3.4-fold, respectively, at 39°C incubation (P < 0.001). Similar results were seen after mitogen stimulation. In subjects responding to TB10.4, the effects were less pronounced and significant only for IP-10. Incubation at 39°C increased IP-10 and IFN-γ responsiveness to both antigens and mitogen in persons with baseline or initial low responses. Adding IL-7 and blocking IL-10 augmented the effects in synergy with fever-range temperature. Incubation at fever-range temperature vividly increases CMI responsiveness to antigen stimulation in vitro in tuberculosis patients and may increase the sensitivity of CMI assays.  相似文献   
995.
RotaTeq (Merck & Co. Inc./Sanofi Pasteur MSD) is a three-dose, oral pentavalent rotavirus vaccine for the immunization of infants from 6 weeks of age for the prevention of rotavirus gastroenteritis. The primary objective of the present trial was to demonstrate that RotaTeq can be coadministered with meningococcal serogroup C conjugate vaccine (MenCC; NeisVac-C; Baxter Healthcare) to healthy infants without impairing the protective immune responses to MenCC. This was an open-label, randomized, comparative study conducted in Finland. The study was designed to assess concomitant versus sequential administration of RotaTeq and MenCC on the immune response to both vaccines. Healthy infants (n = 247), aged 6 to 7 weeks, were recruited. Coadministration of MenCC with RotaTeq was noninferior to sequential administration for the seroprotection rate against meningococcal serogroup C (the proportion of infants with a serum bactericidal antibody titer using baby rabbit complement of ≥ 8 was 100% in both groups). The other responses to MenCC (titer of ≥ 1:128, ≥ 4-fold increase in titer, and geometric mean titers [GMTs]) and the responses to RotaTeq (IgA and SNA response to G1 to G4 and P1A[8], GMTs, and ≥ 3-fold increase in titer) were comparable between groups, including a ≥ 3-fold IgA increase in >96% of the infants in both groups. Concomitant administration of the first doses of MenCC, diphtheria and tetanus toxoids and acellular pertussis vaccine, inactivated poliovirus vaccine, and Haemophilus influenzae type b conjugate vaccine (DTaP-IPV-Hib), and RotaTeq was associated with a higher rate of vomiting and diarrhea than concomitant administration of MenCC and DTaP-IPV-Hib, but that was not observed after the second concomitant administration. The convenience of concomitant administration of RotaTeq and MenCC may, however, outweigh the additive effect of mostly mild adverse events reported after the individual administration of each vaccine. These results support the coadministration of RotaTeq and MenCC.  相似文献   
996.
Mice born from high care‐giving females show, as adults, low anxiety levels, decreased responsiveness to stress, and substantial improvements in cognitive function and hippocampal plasticity. Given the relevance of this issue for preventing emotional and cognitive abnormalities in high‐risk subjects, this study examines the possibility to further enhance the beneficial effects observed in the progeny by augmenting maternal care beyond the highest levels females can display in standard laboratory conditions. This was produced by placing a second female with the dam and its litter in the rearing cage from the partum until pups weaning. Maternal behavior of all females was scored during the first week postpartum, and behavioral indices of emotionality, prestress and poststress corticosterone levels, cognitive performance, and hippocampal morphology were assessed in the adult offspring. We found that pups reared by female dyads received more maternal care than pups reared by dams alone, but as adults, they did not exhibit alterations in emotionality or corticosterone response estimated in basal condition or following restraint stress. Conversely, they showed enhanced performance in hippocampal‐dependent tasks including long‐term object discrimination, reactivity to spatial change, and fear conditioning together with an increase in dendritic length and spine density in the CA1 region of the hippocampus. In general, the beneficial effects of dyadic maternal care were stronger when both the females were lactating. This study demonstrates that double‐mothering exerts a long‐term positive control on cognitive function and hippocampal neuronal connectivity. This experimental manipulation, especially if associated with increased feeding, might offer a concrete possibility to limit or reverse the consequences of negative predisposing conditions for normal cognitive development. © 2010 Wiley‐Liss, Inc.  相似文献   
997.
998.
Brain oscillations constitute a prominent feature of electroencephalography (EEG), in both physiological and pathological states. An efficient separation of oscillation from transient signals in EEG is important not only for detection of oscillations, but also for advanced signal processing such as source localization. A major difficulty lies in the fact that filtering transient phenomena can lead to spurious oscillatory activity. Therefore, in the presence of a mixture of transient and oscillatory events, it is not clear to which extent filtering methods are able to separate them efficiently. The objective of this study was to evaluate methods for separating oscillations from transients. We compared three methods: finite impulse response (FIR) filtering, wavelet analysis with stationary wavelet transform (SWT), time-frequency sparse decomposition with Matching Pursuit (MP). We evaluated the quality of reconstruction and the results of automatic detection of oscillations intermingled with transients. The emphasis of our study was on epileptic signals and single channel processing. In both simulations and on real data, FIR performed generally worse than the time-frequency methods. Both SWT and MP showed good results in separation and detection, each method having its advantages and its limitations. The SWT had good results in separation and detection of transients due to the time invariance property, but still did not completely resolve the frequency overlap for the oscillation during the time-frequency thresholding. The MP provides a sparse representation, and gave good results for simulated data. However, in the real data, we observed distortions introduced by the subtractive approach, and departure from dictionary waveforms. Future directions are proposed for overcoming these limitations.  相似文献   
999.
Accumulation of PrP(Sc), an abnormal form of cellular prion protein (PrP), in the brain of animals and humans leads to fatal neurodegenerative disorders known as prion diseases. Limited protease digestion of PrP(Sc) produces a truncated form called PrP(27-30) that retains prion infectivity and is the main marker of disease targeted in most diagnostic tests. In the search for new anti-prion molecules, drug-screening assays on prion-infected murine cells have been oriented toward decreasing levels of PrP(27-30). In contrast, we screened for drugs promoting multimers of PrP(27-30), illustrating a possible stabilization of mouse PrP(Sc) species, because recent studies aiming to characterize the conformational stability of various prion strains showed that stable recombinant amyloids produced more stable prion strain, leading to longest incubation time. We identified a family of thienyl pyrimidine derivatives that induce SDS-resistant dimers and trimers of PrP(27-30). Bioassays performed on mice brain homogenates treated with these compounds showed that these thienyl pyrimidine derivatives diminished prion infectivity in vivo. Oligomeric-induced activity by thienyl pyrimidine compounds is a promising approach not only to understanding the pathogenesis of prions but also for prion diagnostics. This approach could be extended to other neurodegenerative "prionopathies," such as Alzheimer's, Huntington, or Parkinson's diseases.  相似文献   
1000.
Attention-deficit/hyperactivity disorder (ADHD) was found to be characterized by a deviant pattern of electrocortical activity during resting state, particularly increased theta and decreased beta activity. The first objective of the present study is to confirm whether individuals with slow alpha peak frequency contribute to the finding of increased theta activity in ADHD. The second objective is to explore the relation between resting-state brain oscillations and specific cognitive functions. From 49 boys with ADHD and 49 healthy control boys, resting-state EEG during eyes open and eyes closed was recorded, and a variety of cognitive tasks were administered. Theta and beta power and theta/beta ratio were calculated using both fixed frequency bands and individualized frequency bands. As expected, theta/beta ratio, calculated using fixed frequency bands, was significantly higher in ADHD children than control children. However, this group effect was not significant when theta/beta ratio was assessed using individualized frequency bands. No consistent relation was found between resting-state brain oscillations and cognition. The present results suggest that previous findings of increased theta/beta ratio in ADHD may reflect individuals with slow alpha peak frequencies in addition to individuals with true increased theta activity. Therefore, the often reported theta/beta ratio in ADHD can be considered a non-specific measure combining several distinct neurophysiological subgroups such as frontal theta and slowed alpha peak frequencies. Future research should elucidate the functional role of resting-state brain oscillations by investigating neurophysiological subgroups, which may have a clearer relation to cognitive functions than single frequency bands.  相似文献   
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