Molecular characterization of the fibronectin-binding protein BBK32 of Borrelia burgdorferi sensu lato

BBK32, a fibronectin (Fn)-binding protein of Borrelia (B.) burgdorferi sensu lato (s.l.) which is encoded by the bbk32 gene located on the 36kb linear plasmid (lp36) of isolate B31, is playing an important role in serological diagnosis of Lyme borreliosis. Firstly, we were interested in the genomic localization of bbk32 regarding different B. burgdorferi s.l. species as well as between strains of the same species. Southern blot analyses based on 23 strains of the species B. burgdorferi sensu stricto (s.s.), B. afzelii, B. garinii and B. spielmanii revealed that position of bbk32 is rather variable between the species but also within a given species. bbk32 could be located on different linear plasmids (lp), mainly on lp23kb, lp24kb, lp25kb, lp31kb and lp36kb. The meaning of this finding remains unclear so far. Secondly, a mumber of thirteen chimeric polypeptides representing different parts of the N-terminal regions of BBK32 proteins of both B. burgdorferi s.s. isolate B31 and B. garinii isolate PHei were generated. Fn-binding capabilities of those generated polypeptides were evaluated either by Western-ligand blot-based binding assay or by enzyme-linked immunosorbent assay (ELISA)-based binding assay. Results showed that BBK32 from PHei possesses a higher Fn-binding capability than that from B31. Furthermore, the higher Fn-binding capacity is associated with four amino acids (Lysine131, Lysine145, Threonine147 and Isoleucine155) in the 32-amino acid-long segment (from position 131 to 162). Moreover, both gelatin and collagen could partially inhibit the binding of BBK32 to Fn. This suggests that BBK32 might also bind to the collagen-binding domain of Fn (repeat I6-9 and II1, 2) and partially to its N-terminal fibrin-binding domain (repeat I1-5). Though the meaning of the different Fn-binding capacities remains unclear so far, such studies may provide us with markers to define the different pathogenic potentials of various Borrelia species and strains. Thirdly, eight recombinantly prepared BBK32 homologues (either as partial or as whole) were tested in a line assay to evaluate their contribution for serologic diagnosis of Lyme borreliosis. Though BBK32 homologues could react with sera from Lyme borreliosis patients, compared with other Borrelia-antigens established in the Max von Pettenkofer Institute, these BBK32 homologues could not improve the sensitivity and specificity of the class-specific IgG or IgM antibody tests. Nevertheless, this study underlines the fact that the heterogeneity of Lyme disease Borrelia species must be taken into consideration in the microbiological diagnosis of Lyme borreliosis in European patients.BBK32 ist ein Fibronectin (Fn)-bindendes Protein des Bakteriums Borrelia (B.) burgdorferi sensu lato (s.l.). BBK32 wird durch das bbk32-Gen, das im 36 kb linearen Plasmid (lp36) des Isolates B31 liegt, kodiert und spielt eine wichtige Rolle in serologischen Verfahren für den Nachweis von Lyme Borreliosis. Als erstes waren wir an der Lokalisierung von bbk32-Gen in verschiedenen B. burgdorferi s.l. Spezies sowie in verschiedenen Stämmen derselben Spezi interessiert. Southern-Blot-Analysen von 23 Stämmen der Spezies B. burgdorferi sensu stricto (s.s.), B. afzelii, B. garinii und B. spielmanii zeigten unterschiedliche Lokalisation des bbk32-Gens sowohl in den verschiedenen Spezies, als auch in verschiedenen Stämmen derselben Spezi. Das bbk32-Gen konnte in verschiedenen linearen Plasmiden (lp), hauptsächlich in lp23kb, lp24kb, lp25kb, lp31kb und lp36kb, lokalisiert werden. Die Relevanz dieser unterschiedlichen Lokalisierung ist nicht klar. Zweitens, es wurden 30 chimäre Polypeptid-Sequenzen aus unterschiedlichen Bereichen der N-terminalen Region des BBK32-Proteins von B. burgdorferi s.s. Isolat B31 und B. garinii Isolat PHei generiert. Die Fn-Bindungsfähigkeit dieser hergestellten Polypeptide wurde entweder mittels eines Western-Ligand Blot-basiertes Bindungstestes oder eines Enzymgekoppelter Immunadsorptionstest (ELISA)-basiertes Bindungstestes evaluiert. Die Ergebnisse zeigten, dass BBK32 aus PHei ein höheres Fn-Bindungspotenzial als BBK32-Polypetide aus B31 aufweist. Außerdem ist die höhere Fn-Bindungsfähigkeit mit dem Vorhandensein der vier Aminosäuren: Lysin131, Lysin145, Threonin147 und Isoleucin155 im 32-Aminosäuren langen Segment (von Aminosäure-Position 131 bis 162) assoziiert. Darüber hinaus konnten sowohl Kollagen als auch Gelatine die Bindungsfähigkeit von BBK32 an Fn teilweise inhibieren. Dies deutet darauf hin, dass BBK32 vielleicht auch an Kollagen-Bindungsdomäne in Fn (Motive I6-9 and II1, 2) und teilweise an der N-terminalen Fibrin-Bindungsdomäne (Motive I1-5) binden könnte. Obwohl die Bedeutung der unterschiedlichen Bindungsfähigkeit an Fibronectin noch unklar ist, diese Studie könnte Marker zur Identifizierung diverser Borrelia-Spezies und –Stämme mit unterschiedlichem Pathogenitätspotenzial liefern. Drittens, acht rekombinant hergestellte homologe BBK32-Proteine (gesamte oder nur Teil-Sequenzen des Proteins) wurden für ihre mögliche Verwendung für serologische Verfahren zum Nachweis von Lyme Borreliosis in einem Linientest geprüft. Obwohl BBK32-Homologe mit Seren aus Patienten mit Lyme Borreliosis reagierten, konnten diese, gegenüber anderen im Max von Pettenkofer-Institut etablierten Borrelien-Antigene, zu keiner Erhöhung der Sensitivität und Spezifität des klassenspezifischen Nachweises von IgG oder IgM im Antikörper-Test führen. Nichtsdestoweniger unterstreicht diese Arbeit die Tatsache, dass die Heterogenität der Borrelien-Spezies bei der mikrobiologischen Diagnose von Lyme Borreliosis in Betracht gezogen werden muss

Leakage discharge separation in multi-leaks pipe networks based on improved Independent Component Analysis with Reference (ICA-R) algorithm

The existing leakage assessment methods are not accurate and timely, making it difficult to meet the needs of water companies. In this paper, a methodology based on Independent Component Analysis with Reference (ICA-R) algorithm was proposed to give an more accurate estimation of leakage discharge in multi-leaks water distribution network without considering the specific individuality of one single leak. The proposed algorithm has been improved is improved to prevent error convergence in multi-leak pipe networks. Then an example EPANET model and a physical experimental platform were built to simulate and evaluate the flow in multi-leak WDNs, and the leakage flow rate is calculated by improved ICA-R algorithm and FastICA algorithm. The simulation results are shown the improved ICA-R algorithm has better performanc

A Wireless Passive SAW Delay Line Temperature and Pressure Sensor for Monitoring Water Distribution System

Wireless passive surface acoustic wave (SAW) sensor has been widely used in many applications. This paper presents a feasibility study on a designed wireless passive SAW delay line temperature and pressure sensor for monitoring water distribution systems. The substrate of the sensor node is a Y-Z orientation cut LiNbO3 crystalline with 0.5 mm thickness. The Interdigital transducer (IDT) was fabricated centrally on the surface of the substrate with an antenna connected. There are three reflectors fabricated on the same surface of the IDT. One reflector is on one side and the other two are on the other side of the IDT. A simulated water pipe platform with testing devices was assembled to test the feasibility of the sensor node working in water pipe environment. The experimental result showed that the designed sensor worked properly but 4/5 amplitude of signals is lost compared to the experimental results in the open-air environment

SAW Delay Line based Smart Sensing in Water Distribution System

Wireless Passive Surface Acoustic Wave (SAW) sensors have attracted great attention in numerous applications. They are powered by interrogating Radio Frequency (RF) pulses rather than batteries. In this study, a wireless passive SAW temperature and pressure delay line sensor was adapted in a designed framework which can control the ambient liquid temperature and pressure and characterised. The experimental results meet the theoretical analysis that the related phase delay of the response signal depends linearly on the temperature (pressure) when the pressure (temperature) keeps constant

A Reconstruction and Representation System for 3D Digital Archaeological Documentation – A Case Study of Dahecun Archaeological Site in China

[EN] In Dahecun, a famous archaeological site in China, the cultural strata have accumulated up to 12.5 meters, including archaeological remains covering 3,300 years. In order to improve the precision and convenience of archaeological work, a digitally aided 3D archaeological reconstruction and representation system is designed for the support of archaeological work and subsequent research and virtual reconstruction and representation of immediate site information and research output. The system shall benefit archaeologists and researchers as well as the general population with easy access to archaeological information.[ES] En Dahecun, un famoso sitio arqueológico en China, los estratos culturales se han acumulado durante 3.300 años hasta alcanzar los 12,5 metros de altura. Con el fin de mejorar la precisión y la comodidad de los trabajos arqueológicos, ha sido diseñado un sistema digital de representación y reconstrucción arqueológica 3D como herramienta de apoyo de los trabajos arqueológicos y la posterior investigación y representación y reconstrucción virtual de la información del sitio y resultados de la investigación. El sistema beneficiará a arqueólogos e investigadores, así como a la población en general, facilitando el acceso a la información arqueológica.Xiao, J.; Shang, J.; Gao, M.; Zhang, J.; Li, J. (2015). A Reconstruction and Representation System for 3D Digital Archaeological Documentation – A Case Study of Dahecun Archaeological Site in China. Virtual Archaeology Review. 4(8):50-54. https://doi.org/10.4995/var.2013.4288OJS505448Zhengzhou Municipal Relics and Archaeology Institute (2001): Zhengzhou Dahecun, Science Press, Beijing. China State Administration of Cultural Heritage (2009): Operationa Specifications for Field Archaeology, Cultural Relics Publishing House, Beijing.BI Shuoben, LV Guonian et al. (2011): "Research Framework and Implementation Procedure of Field Archaeology GIS", in China Association of Science and Technology Annual Youth Sympoisum proceeding.ZHAO Congcang (ed.) (2006): An Introduction to Scientific Archaeology, Higher Education Press, Beijing

A Multi-Iteration Enhanced 2P-SMA Method for Improved Error Reduction on a WP-SAW Water Temperature and Pressure Sensor

Due to the instability of the characteristics of materials, fabrication processes and user handling, newly designed and fabricated wireless passive surface acoustic wave (WP-SAW) sensor nodes have inconsistent sensing performance. Furthermore, ambient environmental interferences aggravate inconsistences under complex working conditions. In this paper, a multi-iteration enhanced two-point simple moving average (MI-2P-SMA) method is proposed for sensing error reduction of a WP-SAW reflective delay line water temperature and pressure sensor. This method is improved from the traditional 2P-SMA method for better performance on error reduction. The results show: the MI-2P-SMA method does not change the original characteristics of experimental data; it can reduce relative errors of the WP-SAW reflective delay line water temperature and pressure sensor and has better performance than a traditional 2P-SMA method; it reduces the number of data points and the extent of this reduction is dependent on iteration time

Does Pressure Reduction Test have Significant Effect on Evaluating Pressure Management to Reduce Physical Leakage Amount

Physical leakage flow is positively correlated with water head in water supply network (WSN). Index model is applied to engineering of pressure management in which physical leakage flow is expressed as index of average head in WSN. The paper analyzed three aspects involving flow meter measurement error, water head impact, water flow instability. The result shows that the error of this model is unacceptable from the data of pressure reduction measurement with water flow. Pressure reduction test have meaningless effect on evaluating physical losses reduction unless when it was conducted, users stop consuming water

Leakage control of water distribution system by drop-restore pressure based on viscoelastic mechanism

As a common method to control leakage of water distribution systems, pressure management has the advantages of reducing energy consumption, reducing the possibility of explosion, and avoiding the aggravation of leakage. With the popularization of plastic pipe in the world, it is necessary to study its leakage characteristic in recent years. Our research group carried out leakage experiments on high-density polyethylene (HDPE) pipe, and found that the correlation curve between leakage flow and pressure did not completely coincide in the phase of pressure boost and pressure reduction. The existing FAVAD and exponential leakage models could not explain this phenomenon, which challenges the pressure management theory dominated by a single depressing-pressure process, thus it’s necessary to explore pressure management strategies suitable for plastic pipes. Based on the viscoelastic properties of plastic pipe, we established the viscoelastic leakage model and proposed the leakage control method of drop-restore pressure, and verified its feasibility in practical engineering cases. The main research objectives of this paper will be first to describe the strain response of leakage area in the process of continuous stress application with the Boltzmann superposition principle for HDPE pipe; the Voigt-Kelvin model is used to simulate the creep behavior of viscoelastic material, and a suitable leakage model for viscoelastic pipe is proposed to provide accurate expression of the leakage under the regulation of drop-restore pressure. Secondly, the viscoelastic pipe leakage model is embedded into the pressure-driven analysis model based on non-iterative method and the pressure-driven viscoelastic leakage model is obtained. Finally, evaluating the proposed leakage model in the practical case. With the minimum leakage flow as the objective function, the leakage control model of drop-restore pressure is established and solved by a particle swarm optimization algorithm to obtain an accurate pressure regulation scheme. After applying the scheme from the optimization, the leakage rate decreases from 37.7% to 16.8% on weekdays, which is a great impact on leakage control