Myc-binding Protein Orthologue Interacts with AKAP240 In the Central Pair Apparatus of the \u3cem\u3eChlamydomonas\u3c/em\u3e Flagella

Background Flagella and cilia are fine thread-like organelles protruding from cells that harbour them. The typical ‘9 + 2’ cilia confer motility on these cells. Although the mechanistic details of motility remain elusive, the dynein-driven motility is regulated by various kinases and phosphatases. A-kinase anchoring proteins (AKAPs) are scaffolds that bind to a variety of such proteins. Usually, they are known to possess a dedicated domain that in vitro interacts with the regulatory subunits (RI and RII) present in the cAMP-dependent protein kinase (PKA) holoenzyme. These subunits conventionally harbour contiguous stretches of a.a. residues that reveal the presence of the Dimerization Docking (D/D) domain, Catalytic interface domain and cAMP-Binding domain. The Chlamydomonas reinhardtii flagella harbour two AKAPs; viz., the radial spoke AKAP97 or RSP3 and the central pair AKAP240. Both these were identified on the basis of their RII-binding property. Interestingly, AKAP97 binds in vivo to two RII-like proteins (RSP7 and RSP11) that contain only the D/D domain. Results We found a Chlamydomonas Flagellar Associated Protein (FAP174) orthologous to MYCBP-1, a protein that binds to organellar AKAPs and Myc onco-protein. An in silico analysis shows that the N-terminus of FAP174 is similar to those RII domain-containing proteins that have binding affinities to AKAPs. Binding of FAP174 was tested with the AKAP97/RSP3 using in vitro pull down assays; however, this binding was rather poor with AKAP97/RSP3. Antibodies were generated against FAP174 and the cellular localization was studied using Western blotting and immunoflourescence in wild type and various flagella mutants. We show that FAP174 localises to the central pair of the axoneme. Using overlay assays we show that FAP174 binds AKAP240 previously identified in the C2 portion of the central pair apparatus. Conclusion It appears that the flagella of Chlamydomonas reinhardtii contain proteins that bind to AKAPs and except for the D/D domain, lack the conventional a.a. stretches of PKA regulatory subunits (RSP7 and RSP11). We add FAP174 to this growing list

Effects of Asymmetric Information on Market Timing in the Mutual Fund Industry

Purpose The purpose of this paper is to investigate the effects of information asymmetry (between the realized return and the expected return) on market timing in the mutual fund industry. Design/methodology/approach For the purpose, the authors use a panel of 1,488 active open-end mutual funds for the period 2004-2013. The authors use fund-specific time-dynamic betas. The information asymmetry is measured as the standard deviation of idiosyncratic risk. The data set is decomposed into five market fundamentals in order to emphasis the policy implications of the findings with respect to: equity, fixed income, allocation, alternative, and tax-preferred mutual funds. The empirical evidence is based on endogeneity-robust difference and system generalized method of moments. Findings The following findings are established. First, the information asymmetry broadly follows the same trend as volatility, with a higher sensitivity to market risk exposure. Second, fund managers tend to raise (cutback) their risk exposure in time of high (low) market liquidity. Third, there is evidence of convergence in equity funds. The authors may, therefore, infer that equity funds with lower market risk exposure are catching-up with their counterparts with higher exposure to fluctuation in market conditions. Originality/value The paper complements the sparse literature on market timing in the mutual fund industry with time-dynamic betas, information asymmetry and an endogeneity-robust empirical approac

First description of a Shiga toxin-producing Escherichia coli O103:H2 strain isolated from sheep in Brazil

Univ Estadual Londrina, Dept Microbiol, Londrina, BrazilUniversidade Federal de São Paulo, Dept Microbiol Parasitol & Imunol, São Paulo, BrazilInst Butantan, Bacteriol Lab, São Paulo, BrazilUniv Santiago de Compostela, Fac Vet, Dept Microbiol & Parasitol, Lab Referencia E Coli, Lugo, SpainUniversidade Federal de São Paulo, Dept Microbiol Parasitol & Imunol, São Paulo, BrazilWeb of Scienc

Analyzing the Environmental Impacts and Potential Health Challenges Resulting From Artisanal Gold Mining in Shango Area of Minna, North-Central, Nigeria

The environmental impact and potential health challenges resulting from artisanal mining in Shango area of Minna, North Central Nigeria was put into perspective. The methodology adopted for the research includes field work and laboratory analysis. Results of field observation reveal that mining activity resulted in physical environmental impact such as land degradation, destruction of vegetation, erosion of soils and degrading water quality. Results from the laboratory analyses show that soils are contaminated with elements such as Cu (27.7ppm), Cd (0.6 ppm), Hg (0.62 ppm) and Ag (0.35 ppm) and generally show high status when compared to published standard for upper continental crust. While, Zn (14.8ppm), Ni (7.17ppm), Mn (207ppm), Pb (0.58ppm), As (0.4ppm), Co (0.55ppm), Mo (0.16ppm), and Zr (129.8ppm) are rated low in line with the published standard; other determined elements such as Cr (37.8ppm), Fe (31.1ppm) and Au (0.2ppm) are high. These elements can easily be absorbed by plants and subsequently accumulate in their tissues. When such plants are eventually eaten by man, it may lead to different health problems such as slow growth rate, liver and kidney problem. High concentration of these elements in plant tissues may causes different problems

Equilibrium and stability properties of detonation waves in the hydrodynamic limit of a kinetic model

A shock wave structure problem, like the one which can be formulated for the planar detonation wave, is analyzed here for a binary mixture of ideal gases undergoing the symmetric reaction A1+A1=A2+A2 . The problem is studied at the hydrodynamic Euler limit of a kinetic model of the reactive Boltzmann equation. The chemical rate law is deduced in this frame with a second-order reaction rate, in a hemical regime such that the gas flow is not far away from the chemical equilibrium. The caloric and the thermal equations of state for the specific internal energy and temperature are employed to close the system of balance laws. With respect to other approaches known in the kinetic literature for detonation problems with a reversible reaction, this paper aims to improve some aspects of the wave solution. Within the mathematical analysis of the detonation model, the equation of the equilibrium Hugoniot curve of the final states is explicitly derived for the first time and used to define the correct location of the equilibrium Chapman–Jouguet point in the Hugoniot diagram. The parametric space is widened to investigate the response of the detonation solution to the activation energy of the chemical reaction. Finally, the mathematical formulation of the linear stability problem is given for the wave detonation structure via a normal-mode approach, when bidimensional disturbances perturb the steady solution. The stability equations with their boundary conditions and the radiation condition of the considered model are explicitly derived for small transversal deviations of the shock wave location. The paper shows how a second-order chemical kinetics description, derived at the microscopic level, and an analytic deduction of the equilibrium Hugoniot curve, lead to an accurate picture of the steady detonation with reversible reaction, as well as to a proper bidimensional linear stability analysis.Brazilian Research Council (CNPq), by Italian Research Council GNFM-INdAM, and by the Research Centre of Mathematics of the University of Minho with the Portuguese Funds of FCT, project PEstOE/MAT/UI0013/2014

Prevalence of HEp-2 cell-adherent Escherichia coli and characterisation of enteroaggregative E-coli and chain-like adherent E-coli isolated from children with and without diarrhoea, in Londrina, Brazil

A total of 919 Escherichia coli isolates from 125 children with diarrhoea (cases) and 98 controls were assayed for adherence to HEp-2 cells. Localised adherence was found only in isolates from cases. Diffuse, aggregative (AA), chain-like adherence (CLA) and variants of the AA pattern were found in both cases and controls. the AA isolates were tested for gene sequences associated with enteroaggregative E. coli (EAEC). Only 25% of the isolates hybridised with the EAEC probe, and the aafA, astA and pet gene sequences were found in 7.9%, 44.7% and 7.9% of the isolates, respectively. the aggA gene was not found, although 7.9% were positive for aggC. the CLA isolates reacted with the EAEC probe (55.6%),nd the aggC, astA and pet gene sequences were found in 66.7%, 33.3% and 11.1%, respectively. the aggR (55.6%), aspU (55.6%), shf(33.3%) and she (22.2%) genes were also found in CLA isolates. (C) 2000 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.Univ Estadual Londrina, Dept Microbiol, BR-86051970 Londrina, Pr, BrazilInst Butantan, Lab Especial Microbiol, BR-05503990 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilWeb of Scienc

Evaluation of CIRS String Doppler Phantom as a Test Tool for Use in a Doppler Ultrasound Quality Assurance Program

Ultrasound Doppler systems are routinely used to perform blood flow velocity measurements which assist in the clinical assessment and diagnosis of vascular. Doppler measurements of peak velocities for vascular applications provide an indication of the degree of the stenosis which will ultimately assist in deciding how a patient is managed. It is imperative that Doppler systems are capable of accurately measuring blood flow velocities to ensure correct diagnosis and appropriate patient treatment; therefore such systems should be evaluated regularly as part of a Quality Assurance program. Although a range of Doppler test phantoms have been developed for quality control (QC) purposes to establish the measurement accuracy and stability of Doppler systems only a limited number of such test phantoms are commercially available, the easiest of these devices to operate is the String Phantom. Currently, only one string Doppler phantom is commercially available, namely the CIRS Model 043. In this study an evaluation of the performance of this test device was carried out as a number of problems currently exist with it such as the filament type, the fact that the filament passes through a water–air interface and vibrations from the motor. This study has established that the braided-silk filament, provided with the phantom, should not be used as it introduces errors of as much as 24% for the mean velocity accuracy and 20% for the intrinsic spectral broadening (ISB) depending on the soak time of the filament. Rather, to avoid such errors it is advised that the phantom be retrofitted with a filament made from an O-ring rubber. While this eliminates the temporal changes in backscatter seen with the braided-silk filament, further discrepancies were observed, even with an O-ring filament, when the filament velocity was set in the range 26–44 cm/s, where a resonance effect significantly increased the variability of the maximum velocity accuracy and ISB measurements. This was most likely as a result of the imposed vibrations from the motor, which is mounted directly onto the tank wall; hence, it would prove practical to avoid taking measurements in this velocity range where resonance effects are observed

Review of Ultrasound Elastography Quality Control and Training Test Phantoms

While the rapid development of ultrasound elastography techniques in recent decades has sparked its prompt implementation in the clinical setting adding new diagnostic information to conventional imaging techniques, questions still remain as to its full potential and efficacy in the hospital environment. A limited number of technical studies have objectively assessed the full capabilities of the different elastography approaches, perhaps due, in part, to the scarcity of suitable tissue-mimicking materials and appropriately designed phantoms available. Few commercially-available elastography phantoms possess the necessary test target characteristics or mechanical properties observed clinically, or indeed reflect the lesion-to-background elasticity ratio encountered during clinical scanning. Thus, while some phantoms may prove useful, they may not fully challenge the capabilities of the different elastography technniques, proving limited when it comes to quality control (QC) and/or training purposes. Although a variety of elastography tissue-mimicking materials, such as agar and gelatine dispersions, co-polymer in oil and poly(vinyl) alcohol cryogel, have been developed for specific research purposes, such work has yet to produce appropriately designed phantoms to adequately challenge the variety of current commercially-available elastography applications. Accordingly, there is a clear need for the further development of elastography TMMs and phantoms to keep pace with the rapid developments in elastography technology, to ensure the performance of these new diagnostic approaches are validated, and for clinical training purposes

The Effects of Fatty Desposits on the Accuracy of the Fibroscan Liver Transient Elastography Ultrasound System

A new generation of ultrasound transient elastography (TE) systems have emerged which exploit the well-known correlation between the liver’s pathological and mechanical properties through measurements of the Young’s elastic modulus; however, little work has been carried out to examine the effect that fatty deposits may have on the TE measurement accuracy. An investigation was carried out on the effects on the measurement accuracy of a transient elastography ultrasound system, the Fibroscan®, caused by overlaying fat layers of varying thickness on healthy liver-mimicking phantoms, simulating in vivo conditions for obese patients. Furthermore, a steatosis effect similar to that in non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) was simulated to investigate its effect on the TE system. A range of novel elastography fat-mimicking materials were developed using 6-10wt% poly(vinyl alcohol) cryogel capable of achieving a range of acoustic velocities (1482-1530m/s) and attenuation coefficients (0.4-1dB/MHz/cm) for simulating different liver states. Laboratory-based acoustic velocities and attenuation coefficients were measured while the Young’s modulus was established through a gold standard compression testing method. A significant variation of the Young’s elastic modulus was measured in healthy phantoms with overlaying fat layers of thicknesses exceeding 45mm, impinging on the scanners region of interest, overestimating the compression tested values by up to 11kPa in some cases. Furthermore, Fibroscan® measurements of the steatosis phantoms showed a consistent overestimation (~54%), which strongly suggests that the speed of sound mismatch between that of liver tissue and that assumed by the scanner is responsible for the high clinical cut-offs established in the case of ALD and NAFLD