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11.
Mattsson E Heying R van de Gevel JS Hartung T Beekhuizen H 《FEMS immunology and medical microbiology》2008,52(1):110-117
Staphylococcus aureus is one of the most significant pathogens in human sepsis and endocarditis. A hallmark of these endovascular S. aureus infections is that the coagulation system is triggered by a tissue factor (TF)-dependent pathway. This study demonstrates that highly purified S. aureus peptidoglycan, lipoteichoic acid (LTA) and TSST-1 increase TF mRNA and TF surface protein in human umbilical vein endothelial cells (ECs). Concomitantly, peptidoglycan- and LTA-activated ECs express significant TF-dependent procoagulant activity (TF PCA). In addition peptidoglycan, but not LTA or TSST-1, induced surface expression of the EC inflammation markers ICAM-1 and VCAM-1, which supported the adhesion of monocytes to these ECs. During the coculture of peptidoglycan-activated ECs and adherent monocytes, a marked additional increase of TF PCA was observed. Marginal increases in TF PCA were observed in cocultures of monocytes with LTA- or TSST-1-activated ECs. This study defines in particular staphylococcal peptidoglycan, previously known as a potent initiator of TF PCA in monocytes, as also being an activator of a coagulant response in human ECs that is further intensified by the presence of surface-bound monocytes. 相似文献
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Joke Duyck Katleen Vandamme Stefanie Krausch-Hofmann Lies Boon Katrien De Keersmaecker Eline Jalon Wim Teughels 《PloS one》2016,11(1)
Background
Appropriate oral hygiene is required to maintain oral health in denture wearers. This study aims to compare the role of denture cleaning methods in combination with overnight storage conditions on biofilm mass and composition on acrylic removable dentures.Methods
In a cross-over randomized controlled trial in 13 older people, 4 conditions with 2 different mechanical cleaning methods and 2 overnight storage conditions were considered: (i) brushing and immersion in water without a cleansing tablet, (ii) brushing and immersion in water with a cleansing tablet, (iii) ultrasonic cleaning and immersion in water without a cleansing tablet, and (iv) ultrasonic cleaning and immersion in water with a cleansing tablet. Each test condition was performed for 5 consecutive days, preceded by a 2-days wash-out period. Biofilm samples were taken at baseline (control) and at the end of each test period from a standardized region. Total and individual levels of selected oral bacteria (n = 20), and of Candida albicans were identified using the Polymerase Chain Reaction (PCR) technique. Denture biofilm coverage was scored using an analogue denture plaque score. Paired t-tests and Wilcoxon-signed rank tests were used to compare the test conditions. The level of significance was set at α< 5%.Results
Overnight denture storage in water with a cleansing tablet significantly reduced the total bacterial count (p<0.01). The difference in total bacterial level between the two mechanical cleaning methods was not statistically significant. No significant effect was observed on the amount of Candida albicans nor on the analogue plaque scores.Conclusions
The use of cleansing tablets during overnight denture storage in addition to mechanical denture cleaning did not affect Candida albicans count, but reduced the total bacterial count on acrylic removable dentures compared to overnight storage in water. This effect was more pronounced when combined with ultrasonic cleaning compared to brushing.Trial Registration
ClinicalTrials.gov NCT02454413相似文献15.
Plant growth and fertility strongly depend on environmental conditions such as temperature. Remarkably, temperature also influences meiotic recombination and thus, the current climate change will affect the genetic make-up of plants. To better understand the effects of temperature on meiosis, we followed male meiocytes in Arabidopsis thaliana by live cell imaging under three temperature regimes: at 21°C; at heat shock conditions of 30°C and 34°C; after an acclimatization phase of 1 week at 30°C. This work led to a cytological framework of meiotic progression at elevated temperature. We determined that an increase from 21°C to 30°C speeds up meiosis with specific phases being more amenable to heat than others. An acclimatization phase often moderated this effect. A sudden increase to 34°C promoted a faster progression of early prophase compared to 21°C. However, the phase in which cross-overs mature was prolonged at 34°C. Since mutants involved in the recombination pathway largely did not show the extension of this phase at 34°C, we conclude that the delay is recombination-dependent. Further analysis also revealed the involvement of the ATAXIA TELANGIECTASIA MUTATED kinase in this prolongation, indicating the existence of a pachytene checkpoint in plants, yet in a specialized form.Live cell imaging of plants exposed to different heat stresses provides a temporal framework of meiosis at high temperatures in wild-type and mutants for several meiotic recombination factors. 相似文献
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The outermost layer of the skin, the stratum corneum (SC), comprises the main barrier function between body and environment. The SC features a highly structured lipid organization: a short periodicity phase and a long periodicity phase (LPP) with a repeat distance of 6 and 13 nm, respectively. Like SC, vernix caseosa (VC), the creamy white skin-surface biofilm of the newborn, also contains barrier lipids, i.e. ceramides, cholesterol and free fatty acids. Aim of this study was to investigate whether isolated VC lipids also form the characteristic LPP. Several preparation methods were examined and only when the solution of the lipid mixture, isolated either from VC or SC, was dried under nitrogen at 37 °C and subsequently spread onto a support, the LPP was formed. When VC barrier lipids were first exposed to elevated temperatures and subsequently cooled down, the LPP was formed at around 34 °C, which is at a much lower temperature than observed with the lipids in SC. In conclusion, we showed for the first time that depending on the preparation method, (i) VC lipids also form the LPP and (ii) the LPP in VC lipids and SC lipids was obtained at a low equilibration temperature, mimicking the physiological condition. 相似文献
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Qian Jiang Stacey Arnold Tiffany Heanue Krishna?Praneeth Kilambi Betty Doan Ashish Kapoor Albee?Yun Ling Maria?X. Sosa Moltu Guy Qingguang Jiang Grzegorz Burzynski Kristen West Seneca Bessling Paola Griseri Jeanne Amiel Raquel?M. Fernandez Joke?B.G.M. Verheij Robert?M.W. Hofstra Salud Borrego Stanislas Lyonnet Isabella Ceccherini Jeffrey?J. Gray Vassilis Pachnis Andrew?S. McCallion Aravinda Chakravarti 《American journal of human genetics》2015,96(4):581-596
Innervation of the gut is segmentally lost in Hirschsprung disease (HSCR), a consequence of cell-autonomous and non-autonomous defects in enteric neuronal cell differentiation, proliferation, migration, or survival. Rare, high-penetrance coding variants and common, low-penetrance non-coding variants in 13 genes are known to underlie HSCR risk, with the most frequent variants in the ret proto-oncogene (RET). We used a genome-wide association (220 trios) and replication (429 trios) study to reveal a second non-coding variant distal to RET and a non-coding allele on chromosome 7 within the class 3 Semaphorin gene cluster. Analysis in Ret wild-type and Ret-null mice demonstrates specific expression of Sema3a, Sema3c, and Sema3d in the enteric nervous system (ENS). In zebrafish embryos, sema3 knockdowns show reduction of migratory ENS precursors with complete ablation under conjoint ret loss of function. Seven candidate receptors of Sema3 proteins are also expressed within the mouse ENS and their expression is also lost in the ENS of Ret-null embryos. Sequencing of SEMA3A, SEMA3C, and SEMA3D in 254 HSCR-affected subjects followed by in silico protein structure modeling and functional analyses identified five disease-associated alleles with loss-of-function defects in semaphorin dimerization and binding to their cognate neuropilin and plexin receptors. Thus, semaphorin 3C/3D signaling is an evolutionarily conserved regulator of ENS development whose dys-regulation is a cause of enteric aganglionosis. 相似文献
18.
Brittany E. Evans Kirstin Greaves-Lord Anja S. Euser Joke H. M. Tulen Ingmar H. A. Franken Anja C. Huizink 《PloS one》2013,8(4)
Aims
Abnormal physiological stress reactivity is increasingly investigated as a vulnerability marker for various physical and psychological health problems. However, studies are inconsistent in taking into account potential covariates that may influence the developing stress system. We systematically tested determinants (individual, developmental, environmental and substance use-related) of physiological and perceived physiological stress reactivity. We also examined the relation between physiological and perceived physiological stress reactivity.Method
In a stratified sample of 363 children (7–12 years) and 344 adolescents (13–20 years) from the general population, we examined cortisol, heart rate, respiratory sinus arrhythmia and perceived physiological stress reactivity to a psychosocial stress procedure.Results
Using multivariate linear regression models, we found that individual, developmental, environmental and substance use-related factors were related to each of the stress response indices. These determinant factors were different for each of the stress reactivity indices, and different in children versus adolescents. Perceived physiological stress reactivity predicted cortisol reactivity in adolescents only. All other relations between perceived physiological and physiological stress reactivity were not significant.Conclusions
As physiological stress variables are often examined as vulnerability markers for the development of health problems, we maintain that it is essential that future studies take into consideration factors that may account for found relations. Our study provides an overview and indication of which variables should be considered in the investigation of the relation between physiological stress indices and illness. 相似文献19.
Use of Single-Point Genome Signature Tags as a Universal Tagging Method for Microbial Genome Surveys 下载免费PDF全文
Daniel van der Lelie Celine Lesaulnier Sean McCorkle Joke Geets Safiyh Taghavi John Dunn 《Applied microbiology》2006,72(3):2092-2101
We developed single-point genome signature tags (SP-GSTs), a generally applicable, high-throughput sequencing-based method that targets specific genes to generate identifier tags from well-defined points in a genome. The technique yields identifier tags that can distinguish between closely related bacterial strains and allow for the identification of microbial community members. SP-GSTs are determined by three parameters: (i) the primer designed to recognize a conserved gene sequence, (ii) the anchoring enzyme recognition sequence, and (iii) the type IIS restriction enzyme which defines the tag length. We evaluated the SP-GST method in silico for bacterial identification using the genes rpoC, uvrB, and recA and the 16S rRNA gene. The best distinguishing tags were obtained with the restriction enzyme Csp6I upstream of the 16S rRNA gene, which discriminated all organisms in our data set to at least the genus level and most organisms to the species level. The method was successfully used to generate Csp6I-based tags upstream of the 16S rRNA gene and allowed us to discriminate between closely related strains of Bacillus cereus and Bacillus anthracis. This concept was further used successfully to identify the individual members of a defined microbial community. 相似文献
20.
Reinier P Akkermans Marvin A Berrevoets Ivo J Smeele Annelies E Lucas Bart P Thoonen Joke G Grootens-Stekelenburg Yvonne F Heijdra Chris van Weel Tjard R Schermer 《BMC pulmonary medicine》2012,12(1):1-14