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11.
In recent years parentage control by means of blood grouping tests (blood and protein systems) has been required for bulls to be registered in the Danish Hereford Herd Book. Because the Hereford breed shows less variation in the blood and protein systems, the probability of excluding an incorrectly stated bull (or cow) is estimated to be some 15 % lower in Hereford than in Danish dairy breeds (RDM, SDM and Jersey). 相似文献
12.
Saidi H. Kapiga Fiona M. Ewings Tony Ao Joseph Chilongani Aika Mongi Kathy Baisley Suzanna Francis Aura Andreasen Ramadhan Hashim Deborah Watson-Jones John Changalucha Richard Hayes 《PloS one》2013,8(7)
Objectives
To prepare for future HIV prevention trials, we conducted prospective cohort studies among women working in food and recreational facilities in northern Tanzania. We examined the prevalence and incidence of HIV and HSV-2, and associated risk factors.Methods
Women aged 18–44 years working in food and recreational facilities were screened to determine their eligibility for the studies. Between 2008–2010, HIV-negative women were enrolled and followed for 12 months. At enrolment and 3-monthly, we collected socio-demographic and behavioural data, and performed clinical examinations for collection of biological specimens that were tested for reproductive tract infections. Risk factors for HIV and HSV-2 incidence were investigated using Poisson regression models.Results
We screened 2,229 and enrolled 1,378 women. The median age was 27 years (interquartile range, IQR 22, 33), and median duration working at current facility was 2 years. The prevalences of HIV at screening and HSV-2 at enrolment were 16% and 67%, respectively. Attendance at the 12-month visit was 86%. HIV and HSV-2 incidence rates were 3.7 (95% confidence interval, CI: 2.8,5.1) and 28.6 (95% CI: 23.5,35.0)/100 person-years, respectively. Women who were separated, divorced, or widowed were at increased risk of HIV (adjusted incidence rate ratio, aRR = 6.63; 95% CI: 1.97,22.2) and HSV-2 (aRR = 2.00; 95% CI: 1.15,3.47) compared with married women. Women reporting ≥3 partners in the past 3 months were at higher HIV risk compared with women with 0–1 partner (aRR = 4.75; 95% CI: 2.10,10.8), while those who had reached secondary education or above were at lower risk of HSV-2 compared with women with incomplete primary education (aRR = 0.42; 95% CI: 0.22,0.82).Conclusions
HIV and HSV-2 rates remain substantially higher in this cohort than in the general population, indicating urgent need for effective interventions. These studies demonstrate the feasibility of conducting trials to test new interventions in this highly-mobile population. 相似文献13.
Silvio Schueler Stefan Kapeller Heino Konrad Thomas Geburek Michael Mengl Michele Bozzano Jarkko Koskela François Lefèvre Jason Hubert Hojka Kraigher Roman Longauer Ditte C. Olrik 《Biodiversity and Conservation》2013,22(5):1151-1166
Genetic resources of forest trees are considered as a key factor for the persistence of forest ecosystems because the ability of tree species to survive under changing climate depends strongly on their intraspecific variation in climate response. Therefore, utilizing available genetic variation in climate response and planting alternative provenances suitable for future climatic conditions is considered as an important adaptation measure for forestry. On the other hand, the distribution of adaptive genetic diversity of many tree species is still unknown and the predicted shift of ecological zones and species’ distribution may threaten forest genetic resources that are important for adaptation. Here, we use Norway spruce in Austria as a case study to demonstrate the genetic variation in climate response and to analyse the existing network of genetic conservation units for its effectiveness to safeguard the hotspots of adaptive and neutral genetic diversity of this species. An analysis of the climate response of 480 provenances, clustered into 9 groups of climatically similar provenances, revealed high variation among provenance groups. The most productive and promising provenance clusters for future climates originate from three regions that today depict the warmest and driest areas of the natural spruce distribution in Austria. Gap analysis of the Austrian genetic conservation units in the EUFGIS Portal suggests adequate coverage of the genetic hotspots in southern parts of Austria, but not in eastern and northern Austria. Therefore conservation measures and sustainable utilization of the valuable genetic resources in these regions need to be expanded to cover their high adaptive genetic variation and local adaptation to a warmer climate. The study shows that current conservation efforts need to be evaluated for their effectiveness to protect genetic resources that are important for the survival of trees in a future climate. 相似文献
14.
Simon Glerup Maria Lume Ditte Olsen Jens R. Nyengaard Christian B. Vaegter Camilla Gustafsen Erik I. Christensen Mads Kjolby Anders Hay-Schmidt Dirk Bender Peder Madsen Mart Saarma Anders Nykjaer Claus M. Petersen 《Cell reports》2013,3(1):186-199
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15.
Sarah Preisler Matejka Rebolj Anette Untermann Ditte M?ller Ejegod Elsebeth Lynge Carsten Rygaard Jesper Bonde 《PloS one》2013,8(3)
New commercially available Human Papillomavirus (HPV) assays need to be evaluated in a variety of cervical screening settings. Cobas HPV Test (cobas) is a real-time PCR-based assay allowing for separate detection of HPV genotypes 16 and 18 and a bulk of 12 other high-risk genotypes. The aim of the present study, Horizon, was to assess the prevalence of high-risk HPV infections in an area with a high background risk of cervical cancer, where women aged 23–65 years are targeted for cervical screening. We collected 6,258 consecutive cervical samples from the largest cervical screening laboratory in Denmark serving the whole of Copenhagen. All samples were stored in SurePath media. In total, 5,072 samples were tested with cobas, Hybrid Capture 2 High Risk HPV DNA test (HC2) and liquid-based cytology. Of these, 27% tested positive on cobas. This proportion decreased by age, being 43% in women aged 23–29 years and 10% in women aged 60–65 years. HC2 assay was positive in 20% of samples, and cytology was abnormal (≥ atypical squamous cells of undetermined significance) for 7% samples. When only samples without recent abnormalities were taken into account, 24% tested positive on cobas, 19% on HC2, and 5% had abnormal cytology. The proportion of positive cobas samples was higher than in the ATHENA trial. The age-standardized cobas positivity vs. cytology abnormality was 3.9 in our study and 1.7 in ATHENA. If in Copenhagen the presently used cytology would be replaced by cobas in women above age 30 years, an extra 11% of women would based on historical data be expected to have a positive cobas test without an underlying cervical intraepithelial lesion grade 3 or worse. Countries with a high prevalence of HPV infections should therefore proceed to primary HPV-based cervical screening with caution. 相似文献
16.
Urokinase links plasminogen activation and cell adhesion by cleavage of the RGD motif in vitronectin
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Valentina De Lorenzi Gian Maria Sarra Ferraris Jeppe B Madsen Michela Lupia Peter A Andreasen Nicolai Sidenius 《EMBO reports》2016,17(7):982-998
Components of the plasminogen activation system including urokinase (uPA), its inhibitor (PAI‐1) and its cell surface receptor (uPAR) have been implicated in a wide variety of biological processes related to tissue homoeostasis. Firstly, the binding of uPA to uPAR favours extracellular proteolysis by enhancing cell surface plasminogen activation. Secondly, it promotes cell adhesion and signalling through binding of the provisional matrix protein vitronectin. We now report that uPA and plasmin induces a potent negative feedback on cell adhesion through specific cleavage of the RGD motif in vitronectin. Cleavage of vitronectin by uPA displays a remarkable receptor dependence and requires concomitant binding of both uPA and vitronectin to uPAR. Moreover, we show that PAI‐1 counteracts the negative feedback and behaves as a proteolysis‐triggered stabilizer of uPAR‐mediated cell adhesion to vitronectin. These findings identify a novel and highly specific function for the plasminogen activation system in the regulation of cell adhesion to vitronectin. The cleavage of vitronectin by uPA and plasmin results in the release of N‐terminal vitronectin fragments that can be detected in vivo, underscoring the potential physiological relevance of the process. 相似文献
17.
A specific plasminogen activator inhibitor‐1 antagonist derived from inactivated urokinase
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Zebin Hong Zhonghui Lin Min Liu Guangpu Xue Cai Yuan Lin Lin Barbara Furie Robert Flaumenhaft Peter Andreasen Bruce Furie Mingdong Huang 《Journal of cellular and molecular medicine》2016,20(10):1851-1860
Fibrinolysis is a process responsible for the dissolution of formed thrombi to re‐establish blood flow after thrombus formation. Plasminogen activator inhibitor‐1 (PAI‐1) inhibits urokinase‐type and tissue‐type plasminogen activator (uPA and tPA) and is the major negative regulator of fibrinolysis. Inhibition of PAI‐1 activity prevents thrombosis and accelerates fibrinolysis. However, a specific antagonist of PAI‐1 is currently unavailable for therapeutic use. We screened a panel of uPA variants with mutations at and near the active site to maximize their binding to PAI‐1 and identified a potent PAI‐1 antagonist, PAItrap. PAItrap is the serine protease domain of urokinase containing active‐site mutation (S195A) and four additional mutations (G37bR–R217L–C122A–N145Q). PAItrap inhibits human recombinant PAI‐1 with high potency (Kd = 0.15 nM) and high specificity. In vitro using human plasma, PAItrap showed significant thrombolytic activity by inhibiting endogenous PAI‐1. In addition, PAItrap inhibits both human and murine PAI‐1, allowing the evaluation in murine models. In vivo, using a laser‐induced thrombosis mouse model in which thrombus formation and fibrinolysis are monitored by intravital microscopy, PAItrap reduced fibrin generation and inhibited platelet accumulation following vascular injury. Therefore, this work demonstrates the feasibility to generate PAI‐1 inhibitors using inactivated urokinase. 相似文献
18.
The Drosophila gene, pixie, is an essential gene required for normal growth and translation. Pixie is the fly ortholog of human RLI, which was first identified as an RNase L inhibitor, and yeast Rli1p, which has recently been shown to play a role in translation initiation and ribosome biogenesis. These proteins are all soluble ATP-binding cassette proteins with two N-terminal iron-sulfur clusters. Here we demonstrate that Pixie can be isolated from cells in complex with eukaryotic translation initiation factor 3 and ribosomal proteins of the small subunit. In addition, our analysis of polysome profiles reveals that double-stranded RNA interference-mediated depletion of Pixie results in an increase in empty 80 S ribosomes and a corresponding decrease in polysomes. Thus Pixie is required for normal levels of translation initiation. We also find that Pixie associates with the 40 S subunit on sucrose density gradients in an ATP-dependent manner. Our observations are consistent with Pixie playing a catalytic role in the assembly of complexes required for translation initiation. Thus, the function of this soluble ATP-binding cassette domain protein family in translation initiation has been conserved from yeast through to higher eukaryotes. 相似文献
19.
20.
Checker mallows (Sidalcea, Malvaceae) constitute a western North American genus of annuals and perennials that have been regarded as taxonomically difficult because of complex patterns of morphological variation putatively stemming from hybridization and polyploidy. In recent molecular phylogenetic investigations extensive polymorphism was observed in the internal and external transcribed spacers (ITS and ETS) of 18S-26S nuclear ribosomal DNA for some Sidalcea samples. To resolve the evolutionary basis for this polymorphism and to readdress the evolutionary impact of hybridization in Sidalcea we cloned and sequenced the polymorphic DNAs and included the clones in phylogenetic analyses together with direct sequences of non-polymorphic samples. The positions of cloned spacer sequences in the phylogenetic trees suggest that S. reptans and two subspecies of S. malviflora may have been influenced by past hybridization with lineages of the "glaucescens" clade. Polymorphic sequence patterns in other taxa may be a result of extensive interbreeding within young clades, in keeping with the minimal sequence divergence, largely overlapping geographic distributions and morphology, and ploidy variation in these groups. Other possible explanations for polymorphic sequences in members of Sidalcea include slow concerted evolution relative to mutation rates, incomplete lineage sorting, and recent pseudogene formation. 相似文献