537 research outputs found
IS element IS16 as a molecular screening tool to identify hospital-associated strains of Enterococcus faecium
<p>Abstract</p> <p>Background</p> <p>Hospital strains of <it>Enterococcus faecium </it>could be characterized and typed by various molecular methods (MLST, AFLP, MLVA) and allocated to a distinct clonal complex known as MLST CC17. However, these techniques are laborious, time-consuming and cost-intensive. Our aim was to identify hospital <it>E. faecium </it>strains and differentiate them from colonizing and animal variants by a simple, inexpensive and reliable PCR-based screening assay. We describe here performance and predictive value of a single PCR detecting the insertion element, IS<it>16</it>, to identify hospital <it>E. faecium </it>isolates within a collection of 260 strains of hospital, animal and human commensal origins.</p> <p>Methods</p> <p>Specific primers were selected amplifying a 547-bp fragment of IS<it>16</it>. Presence of IS<it>16 </it>was determined by PCR screenings among the 260 <it>E. faecium </it>isolates. Distribution of IS<it>16 </it>was compared with a prevalence of commonly used markers for hospital strains, <it>esp </it>and <it>hyl</it><sub><it>Efm</it></sub>. All isolates were typed by MLST and partly by PFGE. Location of IS<it>16 </it>was analysed by Southern hybridization of plasmid and chromosomal DNA.</p> <p>Results</p> <p>IS<it>16 </it>was exclusively distributed only among 155 invasive strains belonging to the clonal complex of hospital-associated strains ("CC17"; 28 MLST types) and various vancomycin resistance genotypes (<it>van</it>A/B/negative). The five invasive IS<it>16</it>-negative strains did not belong to the clonal complex of hospital-associated strains (CC17). IS<it>16 </it>was absent in all but three isolates from 100 livestock, food-associated and human commensal strains ("non-CC17"; 64 MLST types). The three IS<it>16</it>-positive human commensal isolates revealed MLST types belonging to the clonal complex of hospital-associated strains (CC17). The values predicting a hospital-associated strain ("CC17") deduced from presence and absence of IS<it>16 </it>was 100% and thus superior to screening for the presence of <it>esp </it>(66%) and/or <it>hyl</it><sub><it>Efm </it></sub>(46%). Southern hybridizations revealed chromosomal as well as plasmid localization of IS<it>16</it>.</p> <p>Conclusions</p> <p>This simple screening assay for insertion element IS<it>16 </it>is capable of differentiating hospital-associated from human commensal, livestock- and food-associated <it>E. faecium </it>strains and thus allows predicting the epidemic strengths or supposed pathogenic potential of a given <it>E. faecium </it>isolate identified within the nosocomial setting.</p
IS element IS16 as a molecular screening tool to identify hospital-associated strains of Enterococcus faecium
<p>Abstract</p> <p>Background</p> <p>Hospital strains of <it>Enterococcus faecium </it>could be characterized and typed by various molecular methods (MLST, AFLP, MLVA) and allocated to a distinct clonal complex known as MLST CC17. However, these techniques are laborious, time-consuming and cost-intensive. Our aim was to identify hospital <it>E. faecium </it>strains and differentiate them from colonizing and animal variants by a simple, inexpensive and reliable PCR-based screening assay. We describe here performance and predictive value of a single PCR detecting the insertion element, IS<it>16</it>, to identify hospital <it>E. faecium </it>isolates within a collection of 260 strains of hospital, animal and human commensal origins.</p> <p>Methods</p> <p>Specific primers were selected amplifying a 547-bp fragment of IS<it>16</it>. Presence of IS<it>16 </it>was determined by PCR screenings among the 260 <it>E. faecium </it>isolates. Distribution of IS<it>16 </it>was compared with a prevalence of commonly used markers for hospital strains, <it>esp </it>and <it>hyl</it><sub><it>Efm</it></sub>. All isolates were typed by MLST and partly by PFGE. Location of IS<it>16 </it>was analysed by Southern hybridization of plasmid and chromosomal DNA.</p> <p>Results</p> <p>IS<it>16 </it>was exclusively distributed only among 155 invasive strains belonging to the clonal complex of hospital-associated strains ("CC17"; 28 MLST types) and various vancomycin resistance genotypes (<it>van</it>A/B/negative). The five invasive IS<it>16</it>-negative strains did not belong to the clonal complex of hospital-associated strains (CC17). IS<it>16 </it>was absent in all but three isolates from 100 livestock, food-associated and human commensal strains ("non-CC17"; 64 MLST types). The three IS<it>16</it>-positive human commensal isolates revealed MLST types belonging to the clonal complex of hospital-associated strains (CC17). The values predicting a hospital-associated strain ("CC17") deduced from presence and absence of IS<it>16 </it>was 100% and thus superior to screening for the presence of <it>esp </it>(66%) and/or <it>hyl</it><sub><it>Efm </it></sub>(46%). Southern hybridizations revealed chromosomal as well as plasmid localization of IS<it>16</it>.</p> <p>Conclusions</p> <p>This simple screening assay for insertion element IS<it>16 </it>is capable of differentiating hospital-associated from human commensal, livestock- and food-associated <it>E. faecium </it>strains and thus allows predicting the epidemic strengths or supposed pathogenic potential of a given <it>E. faecium </it>isolate identified within the nosocomial setting.</p
Interpreting short tandem repeat variations in humans using mutational constraint
Identifying regions of the genome that are depleted of mutations can reveal potentially deleterious variants. Short tandem repeats (STRs), also known as microsatellites, are among the largest contributors of de novo mutations in humans. However, per-locus studies of STR mutations have been limited to highly ascertained panels of several dozen loci. Here, we harnessed bioinformatics tools and a novel analytical framework to estimate mutation parameters for each STR in the human genome by correlating STR genotypes with local sequence heterozygosity. We applied our method to obtain robust estimates of the impact of local sequence features on mutation parameters and used this to create a framework for measuring constraint at STRs by comparing observed vs. expected mutation rates. Constraint scores identified known pathogenic variants with early onset effects. Our metric will provide a valuable tool for prioritizing pathogenic STRs in medical genetics studies
Assessment of cardiovascular risk factors prior to NHS Health Checks in an urban setting: cross-sectional study
OBJECTIVES: To assess the completeness of cardiovascular disease (CVD) risk factor recording and levels of risk factors in patients eligible for the NHS Health Check. DESIGN: Cross-sectional study. SETTING: Twenty-eight general practices located in Hammersmith and Fulham, London, UK. PARTICIPANTS: 42,306 patients aged 40 to 74 years without existing cardiovascular disease or diabetes. MAIN OUTCOME MEASURES: MEASUREMENT AND LEVEL OF CVD RISK FACTORS: blood pressure, cholesterol, body mass index (BMI), blood glucose and smoking status. RESULTS: There was a high recording of smoking status (86.1%) and blood pressure (82.5%); whilst BMI, cholesterol and glucose recording was lower. There was large variation in BMI, cholesterol, glucose recording between practices (29.7-91.5% for BMI). Women had significantly better risk factor recording than men (AOR = 1.70 [1.61-1.80] for blood pressure). All risk factors were better recorded in the least deprived patient group (AOR = 0.79 [0.73-0.85] for blood pressure) and patients with diagnosed hypertension (AOR = 7.24 [6.67-7.86] for cholesterol). Risk factor recording varied considerably between practices but was more strongly associated with patient than practice level characteristics. Age-adjusted levels of cholesterol and BMI were not significantly different between men and women. More men had raised blood glucose, blood pressure and BMI than women (29.7% [29.1-30.4] compared to 19.8% [19.3-20.3] for blood pressure). CONCLUSIONS: Before the NHS Health Check, CVD risk factor recording varied considerably by practice and patient characteristics. We identified significant elevated levels of raised CVD risk factors in the population eligible for a Health Check, which will require considerable work to manage
COMMD1 promotes the ubiquitination of NF‐κB subunits through a cullin‐containing ubiquitin ligase
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102213/1/emboj7601489.pd
The Evolution of Compact Binary Star Systems
We review the formation and evolution of compact binary stars consisting of
white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and
BHs are thought to be the primary astrophysical sources of gravitational waves
(GWs) within the frequency band of ground-based detectors, while compact
binaries of WDs are important sources of GWs at lower frequencies to be covered
by space interferometers (LISA). Major uncertainties in the current
understanding of properties of NSs and BHs most relevant to the GW studies are
discussed, including the treatment of the natal kicks which compact stellar
remnants acquire during the core collapse of massive stars and the common
envelope phase of binary evolution. We discuss the coalescence rates of binary
NSs and BHs and prospects for their detections, the formation and evolution of
binary WDs and their observational manifestations. Special attention is given
to AM CVn-stars -- compact binaries in which the Roche lobe is filled by
another WD or a low-mass partially degenerate helium-star, as these stars are
thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure
Znf202 Affects High Density Lipoprotein Cholesterol Levels and Promotes Hepatosteatosis in Hyperlipidemic Mice
Background: The zinc finger protein Znf202 is a transcriptional suppressor of lipid related genes and has been linked to hypoalphalipoproteinemia. A functional role of Znf202 in lipid metabolism in vivo still remains to be established. Methodology and Principal Findings: We generated mouse Znf202 expression vectors, the functionality of which was established in several in vitro systems. Next, effects of adenoviral znf202 overexpression in vivo were determined in normo- as well as hyperlipidemic mouse models. Znf202 overexpression in mouse hepatoma cells mhAT3F2 resulted in downregulation of members of the Apoe/c1/c2 and Apoa1/c3/a4 gene cluster. The repressive activity of Znf202 was firmly confirmed in an apoE reporter assay and Znf202 responsive elements within the ApoE promoter were identified. Adenoviral Znf202 transfer to Ldlr-/- mice resulted in downregulation of apoe, apoc1, apoa1, and apoc3 within 24 h after gene transfer. Interestingly, key genes in bile flux (abcg5/8 and bsep) and in bile acid synthesis (cyp7a1) were also downregulated. At 5 days post-infection, the expression of the aforementioned genes was normalized, but mice had developed severe hepatosteatosis accompanied by hypercholesterolemia and hypoalphalipoproteinemia. A much milder phenotype was observed in wildtype mice after 5 days of hepatic Znf202 overexpression. Interestingly and similar to Ldl-/- mice, HDL-cholesterol levels in wildtype mice were lowered after hepatic Znf202 overexpression. Conclusion/Significance: Znf202 overexpression in vivo reveals an important role of this transcriptional regulator in liver lipid homeostasis, while firmly establishing the proposed key role in the control of HDL levels
The caudal regeneration blastema is an accumulation of rapidly proliferating stem cells in the flatworm Macrostomum lignano
Background: Macrostomum lignano is a small free-living flatworm capable of regenerating all body parts posterior of the pharynx and anterior to the brain. We quantified the cellular composition of the caudal-most body region, the tail plate, and investigated regeneration of the tail plate in vivo and in semithin sections labeled with bromodeoxyuridine, a marker for stem cells (neoblasts) in S-phase.
Results: The tail plate accomodates the male genital apparatus and consists of about 3,100 cells, about half of which are epidermal cells. A distinct regeneration blastema, characterized by a local accumulation of rapidly proliferating neoblasts and consisting of about 420 cells (excluding epidermal cells), was formed 24 hours after amputation. Differentiated cells in the blastema were observed two days after amputation (with about 920 blastema cells), while the male genital apparatus required four to five days for full differentiation. At all time points, mitoses were found within the blastema. At the place of organ differentiation, neoblasts did not replicate or divide. After three days, the blastema was made of about 1420 cells and gradually transformed into organ primordia, while the proliferation rate decreased. The cell number of the tail plate, including about 960 epidermal cells, was restored to 75% at this time point.
Conclusion: Regeneration after artificial amputation of the tail plate of adult specimens of Macrostomum lignano involves wound healing and the formation of a regeneration blastema. Neoblasts undergo extensive proliferation within the blastema. Proliferation patterns of S-phase neoblasts indicate that neoblasts are either determined to follow a specific cell fate not before, but after going through S-phase, or that they can be redetermined after S-phase. In pulse-chase experiments, dispersed distribution of label suggests that S-phase labeled progenitor cells of the male genital apparatus undergo further proliferation before differentiation, in contrast to progenitor cells of epidermal cells. Mitotic activity and proliferation within the blastema is a feature of M. lignano shared with many other regenerating animals
Early Childhood Caries among a Bedouin community residing in the eastern outskirts of Jerusalem
<p>Abstract</p> <p>Background</p> <p>ECC is commonly prevalent among underprivileged populations. The Jahalin Bedouin are a severely deprived, previously nomadic tribe, dwelling on the eastern outskirts of Jerusalem. The aim of this study was to assess ECC prevalence and potentially associated variables.</p> <p>Methods</p> <p>102 children aged 12–36 months were visually examined for caries, mothers' anterior dentition was visually subjectively appraised, demographic and health behavior data were collected by interview.</p> <p>Results</p> <p>Among children, 17.6% demonstrated ECC, among mothers, 37.3% revealed "fairly bad" anterior teeth. Among children drinking bottles there was about twice the level of ECC (20.3%) than those breast-fed (13.2%). ECC was found only among children aged more than one year (p < 0.001); more prevalent ECC (55.6%) was found among large (10–13 children) families than among smaller families (1–5 children: 13.5%, 6–9 children: 15.6%) (p = 0.009); ECC was more prevalent among children of less educated mothers (p = 0.037); ECC was more prevalent among mothers with "fairly poor" anterior dentition (p = 0.04). Oral hygiene practices were poor.</p> <p>Conclusion</p> <p>ECC levels in this community were not very high but neither low. This changing population might be on the verge of a wider dental disease "epidemic". Public health efforts clearly need to be invested towards the oral health and general welfare of this community.</p
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