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Erik Senneby Torgny Sunnerhagen Björn Hallström Rolf Lood Johan Malmström Christofer Karlsson Magnus Rasmussen 《International journal of medical microbiology : IJMM》2019,309(7):151325
Aerococcus urinae is an emerging pathogen that causes urinary tract infections, bacteremia and infective endocarditis. The mechanisms through which A. urinae cause infection are largely unknown. The aims of this study were to describe the surface proteome of A. urinae and to analyse A. urinae genomes in search for genes encoding surface proteins. Two proteins, denoted Aerococcal surface protein (Asp) 1 and 2, were through the use of mass spectrometry based proteomics found to quantitatively dominate the aerococcal surface. The presence of these proteins on the surface was also shown using ELISA with serum from rabbits immunized with the recombinant Asp. These proteins had a signal sequence in the amino-terminal end and a cell wall-sorting region in the carboxy-terminal end, which contained an LPATG-motif, a hydrophobic domain and a positively charged tail. Twenty-three additional A. urinae genomes were sequenced using Illumina HiSeq technology. Six different variants of asp genes were found (denoted asp1-6). All isolates had either one or two of these asp-genes located in a conserved locus, designated Locus encoding Aerococcal Surface Proteins (LASP). The 25 genomes had in median 13 genes encoding LPXTG-proteins (range 6–24). For other Gram-positive bacteria, cell wall-anchored surface proteins with an LPXTG-motif play a key role for virulence. Thus, it will be of great interest to explore the function of the Asp proteins of A. urinae to establish a better understanding of the molecular mechanisms by which A. urinae cause disease. 相似文献
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João Piedade Johan Nordgren Filipa Esteves Aida Esteves Rosa Teodósio Lennart Svensson Claudia Istrate 《Journal of medical virology》2019,91(6):1014-1021
Norovirus (NoV) and rotavirus group A (RVA) are major agents of acute gastroenteritis worldwide. This study aimed to investigate their epidemiological profile in Portuguese elderly living in long-term care facilities and to assess the host genetic factors mediating infection susceptibility. From November 2013 to June 2015, 636 faecal specimens from 169 elderly, mainly asymptomatic, living in nursing homes in Greater Lisbon and Faro district, Portugal, were collected. NoV and RVA were detected by real-time polymerase chain reaction and NoV genotyped by phylogenetic analysis. NoV detection rate was 7.1% (12 of 169). Three GI.3 and one GII.6 strains were genotyped. RVA detection rate was 3.6% (6 of 169), exclusively in asymptomatic individuals. Host genetic factors associated with infection susceptibility were described on 250 samples by saliva-based enzyme-linked immunosorbent assays. The Lewis-negative phenotype was 8.8% (22 of 250) and the rate of nonsecretors was 16.8% (42 of 250). Association to NoV and RVA infection was performed in the subgroup of individuals (n = 147) who delivered both faecal and saliva samples. The majority of NoV- and RVA-positive individuals (90.9% and 83.3%, respectively) were secretor-positive, with Lewis B phenotype. In a subset of individuals, FUT2 and FUT3 genes were genotyped to assess mutations and validate the secretor and Lewis phenotypes. All sequenced nonsecretors were homozygous for FUT2 nonsense mutation G428A. In this study, low detection rates of NoV and RVA infections were found during two winter seasons. However, even in the absence of any outbreak, the importance of finding these infections in a nonepidemic situation in long-term care facilities may have important implications for infection control. 相似文献
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Hansen Ivo S. Schoonejans Josca M. Sritharan Lathees van Burgsteden Johan A. Ambarus Carmen A. Baeten Dominique L. P. den Dunnen Jeroen 《Inflammation research》2019,68(9):775-785
Inflammation Research - To determine whether ER stress affects the inhibitory pathways of the human immune system, particularly the immunosuppressive effect of IL-10 on macrophages. In vitro... 相似文献
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Sebastiaan ter Horst Ndia Conceio‐Neto Johan Neyts Joana Rocha‐Pereira 《Reviews in medical virology》2019,29(3)
The order of Bunyavirales includes numerous (re)emerging viruses that collectively have a major impact on human and animal health worldwide. There are no vaccines for human use or antiviral drugs available to prevent or treat infections with any of these viruses. The development of efficacious and safe drugs and vaccines is a pressing matter. Ideally, such antivirals possess pan‐bunyavirus antiviral activity, allowing the containment of every bunya‐related threat. The fact that many bunyaviruses need to be handled in laboratories with biosafety level 3 or 4, the great variety of species and the frequent emergence of novel species complicate such efforts. We here examined the potential druggable targets of bunyaviruses, together with the level of conservation of their biological functions, structure, and genetic similarity by means of heatmap analysis. In the light of this, we revised the available models and tools currently available, pointing out directions for antiviral drug discovery. 相似文献
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Fit of implant frameworks: an in vitro comparison between two fabrication techniques 总被引:2,自引:0,他引:2
STATEMENT OF PROBLEM: It has been suggested that a precise fit between the implant and the framework cylinder is necessary to ensure a satisfactory long-term clinical outcome. PURPOSE: The purpose of this study was to compare the precision of fit between implant abutments and framework cylinders in frameworks fabricated by the Procera system and those fabricated from cast gold-alloy. MATERIAL AND METHODS: A total of 19 frameworks, 14 made with the Procera system (type 1) and 5 made of a cast gold-alloy (type 2), were fabricated. A total of 95 implants, 70 type 1 and 25 type 2 frameworks, were evaluated. Three replicas of the space between the implant abutments and the framework cylinders of the master cast were made for each test specimen. The replicas were cut with a scalpel in 2 axial directions: buccal-lingual and right-left. For the purpose of measurement, a microscope with a precision of +/- 0.5 microm was used at original magnification x30. The Student t test was used to determine whether there were significant differences between the framework designs. RESULTS: The buccal-lingual measurements for the type 1 and type 2 frameworks showed mean values of 28.1 microm (SD 9.8) and 42.0 microm (SD 1.8) on the buccal side, respectively, and 25.6 microm (SD 11.2) and 51.6 microm (SD 10.9) on the lingual side, respectively. For the right-left view, the mean measurements were 26.6 microm (SD 8.4) and 49.2 microm (SD 11.4) on the right side, respectively, and 27.4 microm (SD 8.5) and 44.4 microm (SD 6.5) on the left side, respectively. The total mean value for type 1 frameworks was 26.9 microm (SD 9.3); that for type 2 frameworks was 46.8 microm (SD 8.8). CONCLUSION: Within the limitations of this experiment, it was demonstrated that the fit of frameworks made with the Procera system was significantly better than that of the frameworks made with cast gold-alloy (P<.01). 相似文献
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Versloot J Veerkamp JS Hoogstraten J Martens LC 《Community dentistry and oral epidemiology》2004,32(6):456-461
OBJECTIVES: The purpose of this study was (i) to assess the coping strategies of 11-year-old children when dealing with pain at the dentist, (ii) to determine the extent to which the level of the children's dental fear and their experience with pain at the dentist are related to their ability to cope and their choice of strategies, and (iii) to analyse the possible differences between subsamples concerning dental caries. METHODS: The coping strategies were investigated using the Dental Cope Questionnaire (n = 597); the level of dental fear was assessed using the Children's Fear Survey Schedule (CFSS-DS); a question is asked whether a child had experienced pain at the dentist in the past and dental caries was assessed using the DMFS index. RESULTS: The results show that 11-year olds use a variety of coping strategies. Internal strategies are used most frequently, external coping strategies are used less frequently, and destructive strategies are hardly used. The subjects rate internal and external strategies as effective. Children with pain experience and fearful children use more coping strategies, with fearful children using more internal strategies. Reported pain and anxiety were related to the dental status. CONCLUSIONS: The use and choice of coping strategies seems to be at least partly determined by the level of dental fear and the child's experience with pain. 相似文献