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991.
Kei Ohnuma Bart L. Haagmans Ryo Hatano V. Stalin Raj Huihui Mou Satoshi Iwata Nam H. Dang Berend Jan Bosch Chikao Morimoto 《Journal of virology》2013,87(24):13892-13899
We identified the domains of CD26 involved in the binding of Middle East respiratory syndrome coronavirus (MERS-CoV) using distinct clones of anti-CD26 monoclonal antibodies (MAbs). One clone, named 2F9, almost completely inhibited viral entry. The humanized anti-CD26 MAb YS110 also significantly inhibited infection. These findings indicate that both 2F9 and YS110 are potential therapeutic agents for MERS-CoV infection. YS110, in particular, is a good candidate for immediate testing as a therapeutic modality for MERS. 相似文献
992.
Shweta Malik Mariya I. Petrova Ingmar J. J. Claes Tine L. A. Verhoeven Pieter Busschaert Mario Vaneechoutte Bart Lievens Ivo Lambrichts Roland J. Siezen Jan Balzarini Jos Vanderleyden Sarah Lebeer 《Applied and environmental microbiology》2013,79(15):4576-4585
Lactobacilli are important for the maintenance of a healthy ecosystem in the human vagina. Various mechanisms are postulated but so far are poorly substantiated by molecular studies, such as mutant analysis. Bacterial autoaggregation is an interesting phenomenon that can promote adhesion to host cells and displacement of pathogens. In this study, we report on the identification of a human vaginal isolate, Lactobacillus plantarum strain CMPG5300, which shows high autoaggregative and adhesive capacity. To investigate the importance of sortase-dependent proteins (SDPs) in these phenotypes, a gene deletion mutant was constructed for srtA, the gene encoding the housekeeping sortase that covalently anchors these SDPs to the cell surface. This mutant lost the capacity to autoaggregate, showed a decrease in adhesion to vaginal epithelial cells, and lost biofilm-forming capacity under the conditions tested. These results indicate that the housekeeping sortase SrtA of CMPG5300 is a key determinant of the peculiar surface properties of this vaginal Lactobacillus strain. 相似文献
993.
994.
Timothy H. Monk DSc Amy E. Begley Bart D. Billy Mary E. Fletcher Anne Germain Sati Mazumdar 《Chronobiology international》2013,30(1):83-98
A laboratory study of sleep and circadian rhythms was undertaken in 28 spousally bereaved seniors (≥60 yrs) at least four months after the loss event. Measures taken included two nights of polysomnography (second night used), ~36 h of continuous core body temperature monitoring, and four assessments of mood and alertness throughout a day. Preceding the laboratory study, two‐week diaries were completed, allowing the assessment of lifestyle regularity using the 17‐item Social Rhythm Metric (SRM) and the timing of sleep using the Pittsburgh Sleep Diary (PghSD). Also completed were questionnaires assessing level of grief (Texas Revised Inventory of Grief [TRIG] and Index of Complicated Grief [ICG]), subjective sleep quality (Pittsburgh Sleep Quality Index [PSQI]), morningness‐eveningness (Composite Scale of Morningness [CSM]), and clinical interview yielding a Hamilton Depression Rating Scale (HDRS) score. Grief was still present, as indicated by an average TRIG score of about 60. On average, the bereaved seniors habitually slept between ~23:00 and ~06:40 h, achieving ~6 h of sleep with a sleep efficiency of ~80%. They took about 30 min to fall asleep, and had their first REM episode after 75 min. About 20% of their sleep was in Stage REM, and about 3% in Stages 3 or 4 (slow wave sleep). Their mean PSQI score was 6.4. Their circadian temperature rhythms showed the usual classic shape with a trough at ~01:00 h, a fairly steep rise through the morning hours, and a more gradual rise to mid‐evening, with an amplitude of ~0.8°C. In terms of lifestyle regularity, the mean regularity (SRM) score was 3.65 (slightly lower than that usually seen in seniors). Mood and alertness showed time‐of‐day variation with peak alertness in the late morning and peak mood in the afternoon. Correlations between outcome sleep/circadian variables and level of grief (TRIG score) were calculated; there was a slight trend for higher grief to be associated with less time spent asleep (p=0.07) and reduced alertness at 20:00 h (p=0.05). Depression score was not correlated with TRIG score (p>0.20). When subjects were divided into groups by the nature of their late spouse's death (expected/after a long‐term chronic illness [n=18] versus unexpected [n=10]), no differences emerged in any of the variables. In conclusion, when studied at least four months after the loss event, there appears to be some sleep disruption in spousally bereaved seniors. However, this disruption does not appear to be due to bereavement‐related disruptions in the circadian system. 相似文献
995.
Timothy H. Monk Daniel J. Buysse Amy E. Begley Bart D. Billy Mary E. Fletcher 《Chronobiology international》2013,30(3):526-543
Some of the sleep disruption seen in seniors (>65 yrs) may be due to alteration of the circadian pacemaker phase and/or its phase angle with bedtime. The purpose of this study was to determine the effects of 2 h changes in the timing of bedtime (both earlier and later) on the sleep of seniors. Ten healthy seniors (9 F, 1 M, age 70–82 yrs) were each studied individually during three 120 h sessions (each separated by >2 weeks) in a time‐isolation laboratory. On nights 1 and 2, bedtime and rise‐time occurred at the subjects' habitual times; on nights 3–5, bedtime was specified by the experiment, but rise‐time was at the subjects' discretion (without knowledge of clock time). Under the control condition, subjects went to bed at their habitual bedtime (HBT), under the earlier bedtime condition at (HBT?2 h), and under the later bedtime condition at (HBT+2 h). Sleep was polysomnnographically recorded and rectal temperature continuously monitored. Although total sleep time increased in the earlier compared to the later condition (p<0.01), sleep efficiency decreased and wake after sleep onset increased (p<0.01). Subjective ratings of sleep were also worse under the earlier (HBT?2 h) than under later (HBT+ 2 h) condition (p<0.05). Performance did not differ between the earlier and later conditions. The larger the phase angle between actual bedtime and circadian temperature minimum (Tmin), the longer the time spent in bed and total sleep time, and the worse the sleep efficiency and subjective sleep ratings. There were no effects related to the phase angle between Tmin and rise‐time. The relative benefits of longer vs. more efficient sleep in the elderly require further investigation. 相似文献
996.
Kelli Z. Hunsucker Cierra Braga Harrison Gardner Michel Jongerius Roelant Hietbrink Bart Salters 《Biofouling》2013,29(6):658-668
AbstractA two-part study was designed to investigate the efficacy of using UVC to prevent biofouling in the context of ship hull coatings. The first study determined the frequency of UVC required for a coating that does not have any additives (epoxy). It was found that 1?min/day was effective at preventing hard fouling but not biofilm development. The second study addressed several variables: coating type (epoxy, copper, fouling release), frequency of UVC (no exposure, continuous exposure, 1min/6h, 1?min/day), and distance from the lamp (25 and 50?mm). Continuous UVC exposure resulted in no biofouling settlement but it did damage the copper coating. Intermittent UVC exposure was effective at preventing biofouling recruitment to both the copper and the fouling release coatings. Variations were observed with regards to the fouling composition, especially biofilms, sedimentary tubeworms and barnacles, suggesting tolerances within the community. 相似文献
997.
Distribution of mitochondrial haplotypes (cytb) in Polish populations of Emys orbicularis (L., 1758)
Beata Prusak Bart?omiej Najbar S?awomir Mitrus Grzegorz Górecki Urszula Rogalla Grzegorz Grzybowski Adam Hryniewicz Robert Wróblewski Robert Bochen Tomasz Grzybowski 《Biologia》2011,66(5):893-898
The European pond turtle, Emys orbicularis, inhabits a wide distribution area in the western Palaearctic. Polish populations of pond turtle represent the nominotypical
subspecies Emys orbicularis orbicularis. The mitochondrial DNA haplotype (cytb gene) variation among 131 turtles from 26 locations in five regions of Poland was investigated. Five haplotypes belonging
to three distinct lineages were identified. Two clades (I and II) were represented by two haplotypes each, while the other
clade (IV) was represented by one haplotype. Three haplotypes were reported for the first time in E. orbicularis. The eastern part of Poland is inhabited exclusively by turtles bearing haplotype Ia. The remaining four sequence variants
were recorded in western Poland where only the IIb haplotype is considered endemic. The distribution of the other haplotypes
in western Poland could thus reflect past introductions or accidental releases. The authors regarded the two locations (Drzeczkowo
and Karpicko) that were first included in the western Poland populations as autochthonous catchment areas of haplotype Ia. 相似文献
998.
999.
Gijsbers L Man HY Kloet SK de Haan LH Keijer J Rietjens IM van der Burg B Aarts JM 《Analytical biochemistry》2011,(1):77-83
Phosphatidylinositol (PtdIns) is phosphorylated at D-3, D-4, and/or D-5 of the inositol ring to produce seven distinct lipid second messengers known as phosphoinositides (PIs). The PI level is temporally and spatially controlled at the cytosolic face of the cellular membrane. Effectors containing PI-binding domains (e.g., PH, PX, FYVE, ENTH, FERM) associate with specific PIs. This process is crucial for the localization of a variety of cell-signaling proteins, thereby regulating intracellular membrane trafficking, cell growth and survival, cytoskeletal organization, and so on. However, quantitative assessments of protein–PI interactions are generally difficult due to insolubility of PIs in aqueous solution. Here we incorporated PIs into a lipid–protein nanoscale bilayer (nanodisc), which is applied for studying the protein–PI interactions using pull-down binding assay, fluorescence polarization, and nuclear magnetic resonance studies, each facilitating fast, quantitative, and residue-specific evaluation of the protein–PI interactions. Therefore, the PI-incorporated nanodisc could be used as a versatile tool for studying the protein–lipid interactions by various biochemical and biophysical techniques. 相似文献
1000.
ter Haar R Wildschut J Sugih AK Bart Möller W de Waard P Boeriu CG Heeres HJ Schols HA Gruppen H 《Carbohydrate research》2011,(8):12460-1012
To enable enzymatic coupling of saccharides to proteins, several di- and trisaccharides were hydroxy-arylated using anhydrous transesterification with methyl 3-(4-hydroxyphenyl)propionate, catalyzed by potassium carbonate. This transesterification resulted in the attachment of up to 3 hydroxy-aryl units per oligosaccharide molecule, with the monosubstituted product being by far the most abundant. The alkaline reaction conditions, however, resulted in a partial breakdown of reducing sugars. This breakdown could easily be bypassed by a preceding sugar reduction step converting them to polyols. Hydroxy-arylated products were purified by using solid phase extraction, based on the number of hydroxy-aryl moieties attached. Monohydroxy-arylated saccharose was subsequently linked to a tyrosine-containing tripeptide using horseradish peroxidase, as monitored by LC–MSn. This proof of principle for peptide and protein glycation with a range of possible saccharides and glycosidic polyols can lead to products with unique new properties. 相似文献