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11.
Melican K Boekel J Månsson LE Sandoval RM Tanner GA Källskog O Palm F Molitoris BA Richter-Dahlfors A 《Cellular microbiology》2008,10(10):1987-1998
Ascending urinary tract infections can cause extensive damage to kidney structure and function. We have used a number of advanced techniques including multiphoton microscopy to investigate the crucial early phases of uropathogenic Escherichia coli induced pyelonephritis within a living animal. Our results reveal a previously undescribed innate vascular response to mucosal infection, allowing isolation and eradication of the pathogen. The extremely rapid host response to mucosal infection was highlighted by the triggering of a cascade of events within 3-4 h. Epithelial signalling produced an increase in cellular O(2) consumption and affected microvascular flow by clotting, causing localized ischaemia. Subsequent ischaemic damage affected pathophysiology with actin re-arrangement and epithelial sloughing leading to paracellular bacterial movement. A denuded tubular basement membrane is shown to hinder immediate dissemination of bacteria, giving the host time to isolate the infection by clotting. Suppression of clotting by heparin treatment caused fatal urosepsis. Clinically these findings may be relevant in antibiotics delivery in pyelonephritis patients and to the use of anticoagulants in sepsis. 相似文献
12.
Receptor Binding Domain of Escherichia coli F18 Fimbrial Adhesin FedF Can Be both Efficiently Secreted and Surface Displayed in a Functional Form in Lactococcus lactis 下载免费PDF全文
Adherence of F18 fimbrial Escherichia coli to porcine intestinal epithelial cells is mediated by the adhesin (FedF) of F18 fimbriae. In a previous study, we demonstrated the specificity of the amino acid residues between 60 and 109 as the receptor binding domain of FedF. In this study, different expression, secretion, and anchoring systems for the receptor binding domain of the FedF adhesin in Lactococcus lactis were evaluated. Two partially overlapping receptor binding domains (42 and 62 amino acid residues) were expressed as fusions with L. lactis subsp. cremoris protein PrtP for evaluation of secretion efficiency. To evaluate the cell surface display of these FedF-PrtP fusions, they were further combined with different lengths of PrtP spacers fused with either the L. lactis AcmA anchor or the PrtP cell wall binding domain. An HtrA-defective L. lactis NZ9000 mutant was constructed to determine its effect on the level of secreted or anchored fusion proteins. Recombinant L. lactis clones secreting the receptor binding domain of F18 fimbriae as a fusion with the H domains of L. lactis protein PrtP were first constructed by using two different signal peptides. FedF-PrtP fusions, directed by the signal sequence of L. brevis SlpA, were throughout found to be secreted at significantly higher quantities than corresponding fusions with the signal peptide of L. lactis Usp45. In the surface display systems tested, the L. lactis AcmA anchor performed significantly better, particularly in the L. lactis NZ9000ΔhtrA strain, compared to the L. lactis PrtP anchor region. Of the cell surface display constructs with the AcmA anchor, only those with the longest PrtP spacer regions resulted in efficient binding of recombinant L. lactis cells to porcine intestinal epithelial cells. These results confirmed that it is possible to efficiently produce the receptor binding domain of the F18 adhesin in a functionally active form in L. lactis. 相似文献
13.
Agneta Nordenskjöld Fredrik Hedborg Holger Luthman Magnus Nordenskjöld 《Human genetics》1993,92(3):296-298
The Beckwith-Wiedemann syndrome (BWS) is characterized by somatic overgrowth, developmental anomalies, and proneness to embryonic tumor development. The majority of cases are sporadic, but several families with an autosomal dominant mode of inheritance with variable expression and reduced penetrance have been described. In three such families, BWS has been linked to DNA markers for the insulin gene (INS) and H-ras on chromosome band 11p15. Two additional families with inherited BWS are described here. Linkage analysis has been performed with a highly informative marker for the tyrosine hydroxylase (TH) locus within the INS-IGF2 (insulin-like growth factor II)-TH gene cluser and confirms the previous observed linkage to this region (lod score 2.16 at = 0). Linkage analysis to TH provides a basis for informed genetic counselling and carrier detection in the hereditary form of the syndrome. Based on the hypothesis that IGF2 may be a candidate gene for BWS, we screened for mutations in the coding exons 7 and 9, but found no abnormalities in 5 unrelated BWS cases. 相似文献
14.
Introduction
17β-hydroxysteroid dehydrogenases (17βHSDs) are important enzymes regulating the pool of bioactive steroids in the breast. The current study was undertaken in order to evaluate implications of 17βHSD14 in breast cancer, measuring 17βHSD14 protein expression in breast tumours.Methods
An antibody targeting the 17βHSD14 antigen was generated and validated using HSD17B14-transfected cells and a peptide-neutralising assay. Tissue microarrays with tumours from 912 post-menopausal women diagnosed with lymph node-negative breast cancer, and randomised to adjuvant tamoxifen or no endocrine treatment, were analysed for 17βHSD14 protein expression with immunohistochemistry.Results
Results were obtained from 847 tumours. Patients with oestrogen positive tumours with high 17βHSD14 expression had fewer local recurrences when treated with tamoxifen (HR 0.38; 95% C.I. 0.19–0.77, p = 0.007) compared to patients with lower tumoural 17βHSD14 expression, for whom tamoxifen did not reduce the number of local recurrences (HR 1.19; 95% C.I. 0.54–2.59; p = 0.66). No prognostic importance of 17βHSD14 was seen for systemically untreated patients.Conclusions
Using a highly specific validated antibody for immunohistochemical analysis of a large number of breast tumours, we have shown that tumoural expression levels of 17βHSD14 can predict the outcome of adjuvant tamoxifen treatment in terms of local recurrence-free survival in patients with lymph node-negative ER+ breast cancer. The results need be verified to confirm any clinical relevance. 相似文献15.
The anterio-posterior distribution of cholinergic receptor binding sites in human hippocampus (five parts) as well as the effect of age (age range 3 days - 85 years) on receptor properties has been studied. Muscarinic binding sites was measured using labelled quinuclidinyl benzilate (3H-QNB) as ligand and labelled tubocurarine (3H-TC) was used for measurement of nicotine-like binding sites.The highest number of 3H-QNB binding sites in human hippocampus was measured at 3 days and 3 weeks of age and the lowest at 82 years of age. The proportion of high and low affinity muscarinic binding sites respectively was about the same at all ages investigated.A decrease in 3H-QNB binding sites with age was found in the anterior parts of the hippocampus (age range 55–84 years). When individual data for number of 3H-TC binding sites were plotted against corresponding number of 3H-QNB binding sites a strong correlation was observed in most of the different regions of the hippocampus. 相似文献
16.
Agneta L. Sunehag Chiara Dalla Man Gianna Toffolo Morey W. Haymond Dennis M. Bier Claudio Cobelli 《Obesity (Silver Spring, Md.)》2009,17(2):233-239
Given the increase in the incidence of insulin resistance, obesity, and type 2 diabetes in children and adolescents, it would be of paramount importance to assess quantitative indices of insulin secretion and action during a physiological perturbation, such as a meal or an oral glucose‐tolerance test (OGTT). A minimal model method is proposed to measure quantitative indices of insulin secretion and action in adolescents from an oral test. A 7 h, 21‐sample OGTT was performed in 11 adolescents. The C‐peptide minimal model was identified on C‐peptide and glucose data to quantify indices of β‐cell function: static φs and dynamic φd responsivity to glucose from which total responsivity φ was also measured. The glucose minimal model was identified on glucose and insulin data to estimate insulin sensitivity, SI, which was compared to a reference measure, SIref, provided by a tracer method. Disposition indices, which adjust insulin secretion for insulin action, were then calculated. Indices of β‐cell function were φs = 51.35 ± 8.89 × 10?9min?1, φd = 1,392 ± 258 × 10?9, and φ = 82.09 ± 17.70 × 10?9min?1. Insulin sensitivity was SI = 14.19 ± 2.73 × 10?4, not significantly different from SIref = 14.96 ± 3.04 × 10?4 dl/kg·min per µU/ml, and well correlated: r = 0.98, P < 0.0001, thus indicating that SI can be accurately measured from an oral test. Disposition indices were DIs = 1,040 ± 201 × 10?14 dl/kg/min2 per pmol/l, DId = 33,178 ± 10,720 × 10?14 dl/kg/min per pmol/l, DI = 1,844 ± 522 × 10?14 dl/kg/min2 per pmol/l. Virtually the same minimal model assessment was obtained with a reduced 3 h, 9‐sample protocol. OGTT interpreted with C‐peptide and glucose minimal model has the potential to provide novel insight regarding the regulation of glucose metabolism in adolescents, and to evaluate the effect of obesity and interventions such as diet and exercise. 相似文献
17.
18.
Robotics of human movements 总被引:1,自引:0,他引:1
Patrick van der Smagt Markus Grebenstein Holger Urbanek Nadine Fligge Michael Strohmayr Georg Stillfried Jonathon Parrish Agneta Gustus 《Journal of Physiology》2009,103(3-5):119
The construction of robotic systems that can move the way humans do, with respect to agility, stability and precision, is a necessary prerequisite for the successful integration of robotic systems in human environments. We explain human-centered views on robotics, based on the three basic ingredients (1) actuation; (2) sensing; and (3) control, and formulate detailed examples thereof. 相似文献
19.
Niklas?L?fgrenEmail author Emma?Lenholm David?Conradsson Agneta?St?hle Erika?Franzén 《BMC neurology》2014,14(1):235
Background
The Mini-BESTest is a clinical balance test that has shown a high sensitivity in detecting balance impairments in elderly with Parkinson's disease (PD). However, its reproducibility between different raters and between test occasions has yet to be investigated in a clinical context. Moreover, no one has investigated the reproducibility of the Mini-BESTest's subcomponents (i.e. anticipatory postural adjustments; postural responses; sensory orientation and dynamic gait).We aimed to investigate the inter-rater and test-retest reproducibility (reliability as well as agreement) of the Mini-BESTest, as well as its subcomponents, in elderly with mild to moderate PD, performed under conditions assimilating clinical practice.Method
This was an observational measurement study with a test-retest design.Twenty-seven individuals with idiopathic PD (66 - 80 years, mean age: 73; Hoehn & Yahr: 2-3; 1-15 years since diagnosis) were included. Two test administrators, having different experiences with the Mini-BESTest, administered the test individually, in separate rooms in a hospital setting. For the test-retest assessment, all participants returned 7 days after the first test session to perform the Mini-BESTest under similar conditions. Intra-class correlation coefficients (ICC2.1), standard error of measurement (SEMagreement), and smallest real difference (SRD) were analyzed.Results
The Mini-BESTest showed good reliability for both inter-rater and test-retest reproducibility (ICC = 0.72 and 0.80). Regarding agreement, the measurement error (SRD) was found to be 4.1 points (accounting for 15% of the maximal total score) for inter-rater reproducibility and 3.4 points (12% of the maximal total score) for test-retest reproducibility. The investigation of the Mini-BESTest's subcomponents showed a similar pattern for both inter-rater and test-retest reproducibility, where postural responses had the largest proportional measurement error, and sensory orientation showed the highest agreement.Conclusions
Our findings indicate that the Mini-BESTest is able to distinguish between individuals with mild to moderate PD; however, when used in clinical balance assessments, the large measurement error needs to be accounted for.20.
Niels Andreasen Monica Simeoni Henrik Ostlund Pia I. Lisjo Tormod Fladby Amy E. Loercher Gerard J. Byrne Frances Murray Paul T. Scott-Stevens Anders Wallin Yinghua Y. Zhang Lena H. Bronge Henrik Zetterberg Agneta K. Nordberg Astrid J. Yeo Shahid A. Khan Jan Hilpert Prafull C. Mistry 《PloS one》2015,10(3)