Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

Science.gov (United States)

Andrews, Joel F.; Sykora, Landon J.; Barik-Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna; Barik, Sailen; Shevde, Lalita A.; Samant, Rajeev S.

2012-01-01

HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington’s, Parkinson’s diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S). PMID:22504047

Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

International Nuclear Information System (INIS)

Andrews, Joel F.; Sykora, Landon J.; Barik Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna; Barik, Sailen; Shevde, Lalita A.; Samant, Rajeev S.

2012-01-01

HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington's, Parkinson's diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S).

Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

Energy Technology Data Exchange (ETDEWEB)

Andrews, Joel F.; Sykora, Landon J.; Barik Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Barik, Sailen [Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Science, Cleveland State University, Cleveland, OH (United States); Shevde, Lalita A. [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Samant, Rajeev S., E-mail: rsamant@usouthal.edu [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States)

2012-06-10

HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington's, Parkinson's diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S).

Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

Energy Technology Data Exchange (ETDEWEB)

Andrews, Joel F.; Sykora, Landon J.; Barik Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Barik, Sailen [Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Science, Cleveland State University, Cleveland, OH (United States); Shevde, Lalita A. [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Samant, Rajeev S., E-mail: rsamant@usouthal.edu [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States)

2012-06-10

HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington's, Parkinson's diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S).

Large Isoform of Mammalian Relative of DnaJ is a Major Determinant of Human Susceptibility to HIV-1 Infection

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Yu-Ping Chiang

2014-12-01

Full Text Available Individual differences in susceptibility to human immunodeficiency virus type 1 (HIV-1 infection have been of interest for decades. We aimed to determine the contribution of large isoform of Mammalian DnaJ (MRJ-L, a HIV-1 Vpr-interacting cellular protein, to this natural variation. Expression of MRJ-L in monocyte-derived macrophages was significantly higher in HIV-infected individuals (n = 31 than their uninfected counterparts (n = 27 (p = 0.009. Fifty male homosexual subjects (20 of them are HIV-1 positive were further recruited to examine the association between MRJ-L levels and occurrence of HIV infection. Bayesian multiple logistic regression revealed that playing a receptive role and increased levels of MRJ-L in macrophages were two risk factors for HIV-1 infection. A 1% rise in MRJ-L expression was associated with a 1.13 fold (95% CrI 1.06–1.29 increase in odds of contracting HIV-1 infection. Ex vivo experiments revealed that MRJ-L facilitated Vpr-dependent nuclear localization of virus. Infection of macrophage-tropic strain is a critical step in HIV-1 transmission. MRJ-L is a critical factor in this process; hence, subjects with higher macrophage MRJ-L levels are more vulnerable to HIV-1 infection.

Program 6 Technical Interchange Meeting Proceedings

Science.gov (United States)

1992-10-01

Buteau PRC (703)556-1355 Gary R. Dolson PRC (703) 5561859 David J. Gray Sterling (315)336-0500 Noreen S. Heyda Harris (407)984-6384 Jay Jesse GTE (719)570...Reed Sterling John Sautter Sterling (315)336-0500 Kevin Sculley PRC (402)291-5533 Stefan Shrier MRJ (703)934-9249 Peter Soliz Orion (505)262-2260...4730 Howard A. Melching GTE (719)570-8898 Noreen S. Heyda Harris (407)984-6384 Jonathan H. Reed Harris (407)984-6008 Stefan Shrier MRJ (703) 934-9249

Characterization of maximally random jammed sphere packings. III. Transport and electromagnetic properties via correlation functions

Science.gov (United States)

Klatt, Michael A.; Torquato, Salvatore

2018-01-01

In the first two papers of this series, we characterized the structure of maximally random jammed (MRJ) sphere packings across length scales by computing a variety of different correlation functions, spectral functions, hole probabilities, and local density fluctuations. From the remarkable structural features of the MRJ packings, especially its disordered hyperuniformity, exceptional physical properties can be expected. Here we employ these structural descriptors to estimate effective transport and electromagnetic properties via rigorous bounds, exact expansions, and accurate analytical approximation formulas. These property formulas include interfacial bounds as well as universal scaling laws for the mean survival time and the fluid permeability. We also estimate the principal relaxation time associated with Brownian motion among perfectly absorbing traps. For the propagation of electromagnetic waves in the long-wavelength limit, we show that a dispersion of dielectric MRJ spheres within a matrix of another dielectric material forms, to a very good approximation, a dissipationless disordered and isotropic two-phase medium for any phase dielectric contrast ratio. We compare the effective properties of the MRJ sphere packings to those of overlapping spheres, equilibrium hard-sphere packings, and lattices of hard spheres. Moreover, we generalize results to micro- and macroscopically anisotropic packings of spheroids with tensorial effective properties. The analytic bounds predict the qualitative trend in the physical properties associated with these structures, which provides guidance to more time-consuming simulations and experiments. They especially provide impetus for experiments to design materials with unique bulk properties resulting from hyperuniformity, including structural-color and color-sensing applications.

Electrorheology leads to healthier and tastier chocolate.

Science.gov (United States)

Tao, Rongjia; Tang, Hong; Tawhid-Al-Islam, Kazi; Du, Enpeng; Kim, Jeongyoo

2016-07-05

Chocolate is one of the most popular food types and flavors in the world. Unfortunately, at present, chocolate products contain too much fat, leading to obesity. Although this issue was called into attention decades ago, no actual solution was found. To bypass this critical outstanding problem, two manufacturers introduced some low-calorie fats to substitute for cocoa butter. Somehow, their products are not allowed in most countries. Here we show that this issue is deeply related to the basic science of soft matter, especially to the viscosity of liquid suspension and maximally random jammed (MRJ) density. When the concentration of cocoa solid is high, close to the MRJ density, removing a small amount of fat will jam the chocolate flow. Applying unconventional electrorheology to liquid chocolate with applied field in the flow direction, we aggregate the cocoa particles into prolate spheroids in micrometers. This microstructure change breaks the rotational symmetry, reduces liquid chocolate's viscosity along the flow direction, and increases its MRJ density significantly. Hence the fat level in chocolate can be effectively reduced. We are expecting a new class of healthier and tastier chocolate soon.

Electrorheology leads to healthier and tastier chocolate

Science.gov (United States)

Tao, Rongjia; Tang, Hong; Tawhid-Al-Islam, Kazi; Du, Enpeng; Kim, Jeongyoo

2016-01-01

Chocolate is one of the most popular food types and flavors in the world. Unfortunately, at present, chocolate products contain too much fat, leading to obesity. Although this issue was called into attention decades ago, no actual solution was found. To bypass this critical outstanding problem, two manufacturers introduced some low-calorie fats to substitute for cocoa butter. Somehow, their products are not allowed in most countries. Here we show that this issue is deeply related to the basic science of soft matter, especially to the viscosity of liquid suspension and maximally random jammed (MRJ) density. When the concentration of cocoa solid is high, close to the MRJ density, removing a small amount of fat will jam the chocolate flow. Applying unconventional electrorheology to liquid chocolate with applied field in the flow direction, we aggregate the cocoa particles into prolate spheroids in micrometers. This microstructure change breaks the rotational symmetry, reduces liquid chocolate’s viscosity along the flow direction, and increases its MRJ density significantly. Hence the fat level in chocolate can be effectively reduced. We are expecting a new class of healthier and tastier chocolate soon. PMID:27325758

Markers for Routine Assessment of Fatigue and Recovery in Male and Female Team Sport Athletes during High-Intensity Interval Training

Science.gov (United States)

Wiewelhove, Thimo; Raeder, Christian; Meyer, Tim; Kellmann, Michael; Pfeiffer, Mark; Ferrauti, Alexander

2015-01-01

Aim Our study aimed to investigate changes of different markers for routine assessment of fatigue and recovery in response to high-intensity interval training (HIIT). Methods 22 well-trained male and female team sport athletes (age, 23.0 ± 2.7 years; V̇O2max, 57.6 ± 8.6 mL·min·kg−1) participated in a six-day running-based HIIT-microcycle with a total of eleven HIIT sessions. Repeated sprint ability (RSA; criterion measure of fatigue and recovery), countermovement jump (CMJ) height, jump efficiency in a multiple rebound jump test (MRJ), 20-m sprint performance, muscle contractile properties, serum concentrations of creatinkinase (CK), c-reactive protein (CRP) and urea as well as perceived muscle soreness (DOMS) were measured pre and post the training program as well as after 72 h of recovery. Results Following the microcycle significant changes (p < 0.05) in RSA as well as in CMJ and MRJ performance could be observed, showing a decline (%Δ ± 90% confidence limits, ES = effect size; RSA: -3.8 ± 1.0, ES = -1.51; CMJ: 8.4 ± 2.9, ES = -1.35; MRJ: 17.4 ± 4.5, ES = -1.60) and a return to baseline level (RSA: 2.8 ± 2.6, ES = 0.53; CMJ: 4.1 ± 2.9, ES = 0.68; MRJ: 6.5 ± 4.5, ES = 0.63) after 72 h of recovery. Athletes also demonstrated significant changes (p < 0.05) in muscle contractile properties, CK, and DOMS following the training program and after the recovery period. In contrast, CRP and urea remained unchanged throughout the study. Further analysis revealed that the accuracy of markers for assessment of fatigue and recovery in comparison to RSA derived from a contingency table was insufficient. Multiple regression analysis also showed no correlations between changes in RSA and any of the markers. Conclusions Mean changes in measures of neuromuscular function, CK and DOMS are related to HIIT induced fatigue and subsequent recovery. However, low accuracy of a single or combined use of these markers requires the verification of their applicability on an

Markers for Routine Assessment of Fatigue and Recovery in Male and Female Team Sport Athletes during High-Intensity Interval Training.

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Thimo Wiewelhove

Full Text Available Our study aimed to investigate changes of different markers for routine assessment of fatigue and recovery in response to high-intensity interval training (HIIT.22 well-trained male and female team sport athletes (age, 23.0 ± 2.7 years; V̇O2 max, 57.6 ± 8.6 mL · min · kg(-1 participated in a six-day running-based HIIT-microcycle with a total of eleven HIIT sessions. Repeated sprint ability (RSA; criterion measure of fatigue and recovery, countermovement jump (CMJ height, jump efficiency in a multiple rebound jump test (MRJ, 20-m sprint performance, muscle contractile properties, serum concentrations of creatinkinase (CK, c-reactive protein (CRP and urea as well as perceived muscle soreness (DOMS were measured pre and post the training program as well as after 72 h of recovery.Following the microcycle significant changes (p < 0.05 in RSA as well as in CMJ and MRJ performance could be observed, showing a decline (%Δ ± 90% confidence limits, ES = effect size; RSA: -3.8 ± 1.0, ES = -1.51; CMJ: 8.4 ± 2.9, ES = -1.35; MRJ: 17.4 ± 4.5, ES = -1.60 and a return to baseline level (RSA: 2.8 ± 2.6, ES = 0.53; CMJ: 4.1 ± 2.9, ES = 0.68; MRJ: 6.5 ± 4.5, ES = 0.63 after 72 h of recovery. Athletes also demonstrated significant changes (p < 0.05 in muscle contractile properties, CK, and DOMS following the training program and after the recovery period. In contrast, CRP and urea remained unchanged throughout the study. Further analysis revealed that the accuracy of markers for assessment of fatigue and recovery in comparison to RSA derived from a contingency table was insufficient. Multiple regression analysis also showed no correlations between changes in RSA and any of the markers.Mean changes in measures of neuromuscular function, CK and DOMS are related to HIIT induced fatigue and subsequent recovery. However, low accuracy of a single or combined use of these markers requires the verification of their applicability on an individual basis.

Hyperuniformity, quasi-long-range correlations, and void-space constraints in maximally random jammed particle packings. II. Anisotropy in particle shape.

Science.gov (United States)

Zachary, Chase E; Jiao, Yang; Torquato, Salvatore

2011-05-01

We extend the results from the first part of this series of two papers by examining hyperuniformity in heterogeneous media composed of impenetrable anisotropic inclusions. Specifically, we consider maximally random jammed (MRJ) packings of hard ellipses and superdisks and show that these systems both possess vanishing infinite-wavelength local-volume-fraction fluctuations and quasi-long-range pair correlations scaling as r(-(d+1)) in d Euclidean dimensions. Our results suggest a strong generalization of a conjecture by Torquato and Stillinger [Phys. Rev. E 68, 041113 (2003)], namely, that all strictly jammed saturated packings of hard particles, including those with size and shape distributions, are hyperuniform with signature quasi-long-range correlations. We show that our arguments concerning the constrained distribution of the void space in MRJ packings directly extend to hard-ellipse and superdisk packings, thereby providing a direct structural explanation for the appearance of hyperuniformity and quasi-long-range correlations in these systems. Additionally, we examine general heterogeneous media with anisotropic inclusions and show unexpectedly that one can decorate a periodic point pattern to obtain a hard-particle system that is not hyperuniform with respect to local-volume-fraction fluctuations. This apparent discrepancy can also be rationalized by appealing to the irregular distribution of the void space arising from the anisotropic shapes of the particles. Our work suggests the intriguing possibility that the MRJ states of hard particles share certain universal features independent of the local properties of the packings, including the packing fraction and average contact number per particle.

Espaço urbano e a mortalidade por doença isquêmica do coração em idosos no Rio de Janeiro Espacio urbano y la mortalidad por enfermedad isquémica del corazón en adultos mayores en Rio de Janeiro Urban space and mortality from ischemic heart disease in the elderly in Rio de Janeiro

Directory of Open Access Journals (Sweden)

Germana Périssé

2010-04-01

Full Text Available FUNDAMENTO: As doenças cardiovasculares são a primeira causa de morte no Brasil, especialmente entre idosos. No município do Rio de Janeiro (MRJ, predomina a mortalidade por doenças isquêmicas do coração (DIC. Estudos mostram uma associação entre o processo de urbanização, as condições socioeconômicas e a mudança no estilo de vida com a ocorrência de DIC. OBJETIVO: Descrever a distribuição geográfica da taxa de mortalidade por DIC em idosos do MRJ em 2000 e sua correlação com variáveis socioeconômicas. MÉTODOS: Estudo ecológico, com análise espacial da distribuição da taxa de mortalidade por DIC em idosos que residiam no MRJ em 2000, padronizada por sexo e faixa etária, e de suas correlações com variáveis socioeconômicas do censo demográfico. RESULTADOS: Não foram observadas correlações fortes entre as variáveis socioeconômicas e a mortalidade por DIC em idosos no âmbito dos bairros. Algumas correlações encontradas, embora fracas, apontaram uma maior mortalidade associada a um melhor nível socioeconômico. Após correção da taxa de mortalidade por DIC por meio do acréscimo das causas mal definidas (CMD de óbito, algumas associações adquiriram o sentido de piores condições socioeconômicas e maior mortalidade por DIC. Foi encontrada dependência espacial para variáveis socioeconômicas, mas não para a mortalidade por DIC. CONCLUSÃO: A dependência espacial encontrada nas variáveis socioeconômicas mostra que o espaço urbano no MRJ, embora heterogêneo, possui certa dose de discriminação no âmbito dos bairros. Algumas correlações encontradas entre DIC e variáveis socioeconômicas apresentaram sentido oposto ao da literatura, o que pode estar em parte relacionado às proporções de CMD ou ao perfil distinto nessa faixa etária.FUNDAMENTO: Las enfermedades cardiovasculares son la primera causa de muerte en Brasil, especialmente en adultos mayores. En el municipio de Rio de Janeiro (MRJ

NMR spectroscopy of muscle proteins; Spektroskopia MRJ bialek miesniowych

Energy Technology Data Exchange (ETDEWEB)

Slosarek, G. [Inst. Fizyki, Univ. A. Mickiewicza, Poznan (Poland)

1995-12-31

Author reviews various experimental techniques used for study of the structure of muscle proteins. Difficulties of application of NMR are described. Studies of the influence of Ca{sup 2+} on flexibility of actin polymer are presented. 11 refs, 3 figs.

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Indian Academy of Sciences (India)

The solid line shows schematically the pressure-density relationship for cold matter. The dashed lines show the pressure PI1 needed to balance gravity in a body of mass M and radius R as a function of its density p. Intersection with the solid line is the condition for equilibrium P oc (GM. 2. ) / R 2 = GM 2 • Since p oc M/RJ ,.

The Perfect Glass Paradigm: Disordered Hyperuniform Glasses Down to Absolute Zero

Science.gov (United States)

Zhang, G.; Stillinger, F. H.; Torquato, S.

2016-11-01

Rapid cooling of liquids below a certain temperature range can result in a transition to glassy states. The traditional understanding of glasses includes their thermodynamic metastability with respect to crystals. However, here we present specific examples of interactions that eliminate the possibilities of crystalline and quasicrystalline phases, while creating mechanically stable amorphous glasses down to absolute zero temperature. We show that this can be accomplished by introducing a new ideal state of matter called a “perfect glass”. A perfect glass represents a soft-interaction analog of the maximally random jammed (MRJ) packings of hard particles. These latter states can be regarded as the epitome of a glass since they are out of equilibrium, maximally disordered, hyperuniform, mechanically rigid with infinite bulk and shear moduli, and can never crystallize due to configuration-space trapping. Our model perfect glass utilizes two-, three-, and four-body soft interactions while simultaneously retaining the salient attributes of the MRJ state. These models constitute a theoretical proof of concept for perfect glasses and broaden our fundamental understanding of glass physics. A novel feature of equilibrium systems of identical particles interacting with the perfect-glass potential at positive temperature is that they have a non-relativistic speed of sound that is infinite.

Increasing the maximally random jammed density with electric field to reduce the fat level in chocolate

Science.gov (United States)

Tao, R.; Tang, H.

Chocolate is one of the most popular food types and flavors in the world. Unfortunately, at present, chocolate products contain too much fat, leading to obesity. For example, a typical molding chocolate has various fat up to 40% in total and chocolate for covering ice cream has fat 50 -60%. Especially, as children are the leading chocolate consumers, reducing the fat level in chocolate products to make them healthier is important and urgent. While this issue was called into attention and elaborated in articles and books decades ago and led to some patent applications, no actual solution was found unfortunately. Why is reducing fat in chocolate so difficult? What is the underlying physical mechanism? We have found that this issue is deeply related to the basic science of soft matters, especially to their viscosity and maximally random jammed (MRJ) density φx. All chocolate productions are handling liquid chocolate, a suspension with cocoa solid particles in melted fat, mainly cocoa butter. The fat level cannot be lower than 1-φxin order to have liquid chocolate to flow. Here we show that that with application of an electric field to liquid chocolate, we can aggregate the suspended particles into prolate spheroids. This microstructure change reduces liquid chocolate's viscosity along the flow direction and increases its MRJ density significantly. Hence the fat level in chocolate can be effectively reduced. We are looking forward to a new class of healthier and tasteful chocolate coming to the market soon. Dept. of Physics, Temple Univ, Philadelphia, PA 19122.

MRI compatibility of robot actuation techniques--a comparative study.

Science.gov (United States)

Fischer, Gregory S; Krieger, Axel; Iordachita, Iulian; Csoma, Csaba; Whitcomb, Louis L; Gabor, Fichtinger

2008-01-01

This paper reports an experimental evaluation of the following three different MRI-compatible actuators: a Shinsei ultrasonic motor a Nanomotion ultrasonic motor and a pneumatic cylinder actuator. We report the results of a study comparing the effect of these actuators on the signal to noise ratio (SNR) of MRJ images under a variety of experimental conditions. Evaluation was performed with the controller inside and outside the scanner room and with both 1.5T and 3T MRI scanners. Pneumatic cylinders function with no loss of SNR with controller both inside and outside of the scanner room. The Nanomotion motor performs with moderate loss of SNR when moving during imaging. The Shinsei is unsuitable for motion during imaging. All may be used when motion is appropriately interleaved with imaging cycles.

Immunochemical analysis of Micrococcus lysodeikticus (luteus) F1-ATPase and its subunits.

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Urban, C; Salton, M R

1983-08-31

The F1-ATPase from Micrococcus lysodeikticus has been purified to 95% protein homogeneity in this laboratory and as all other bacterial F1S, possesses five distinct subunits with molecular weights ranging from 60 000 to 10 000 (Huberman, M. and Salton, M.R.J. (1979) Biochim. Biophys. Acta 547, 230-240). In this communication, we demonstrate the immunochemical reactivities of antibodies to native and SDS-dissociated subunits with the native and dissociated F1-ATPase and show that: (1) the antibodies generated to the native or SDS-dissociated subunits react with the native molecule; (2) all of the subunits comprising the F1 are antigenically unique as determined by crossed immunoelectrophoresis and the Ouchterlony double-diffusion techniques; (3) antibodies to the SDS-denatured individual delta- and epsilon-subunits can be used to destabilize the interaction of these specific subunits with the rest of the native F1; and (4) all subunit antibodies as well as anti-native F1 were found to inhibit ATPase activity to varying degrees, the strongest inhibition being seen with antibodies to the total F1 and anti-alpha- and anti-beta-subunit antibodies. The interaction of specific subunit antibodies may provide a new and novel way to study further and characterize the catalytic portions of F1-ATPases and in general may offer an additional method for the examination of multimeric proteins.

Magnetic resonance imaging findings compared with histological findings of the labrum in hip osteoarthritis

International Nuclear Information System (INIS)

Kanezaki, Shiho; Nakamura, Shigeru; Matsushita, Takashi; Yamamoto, Asako; Osawa, Marie

2015-01-01

Patients with disorders such as acetabular dysplasia or femoroacetabular impingement are at risk of developing hip osteoartbritis. Assessment of the cartilage and labrum in the hip joint based on magnetic resonance imaging (MRI) has been challenging because of the low signal-to-noise ratio (SNR) due to its deep location, ball and socket structure, and small volume of those structures compared with the whole joint size. To achieve better imaging assessment, direct MR. arthrography (d-MRA) and other techniques such as T2* mapping, T2 mapping, Tlrho, and delayed gadolinium-enhanced MRI (dGEMRIC) have been developed along with the increasing use of high-field MRI. In patients with no apparent osteoarthritic changes such as joint space narrowing or osteophyte and subchondral cyst formation on radiographs, these techniques can detect early cartilage or labral damage. A recently developed semiquantitative MRI-based scoring system for hip osteoarthritis includes evaluation of the labrum, and its application as a potential therapeutic monitoring tool is anticipated. The labrum shows pathological changes such as macroscopic hypertrophy and histological degeneration in hip osteoartbritis, but the pathological background is not well understood when evaluated by MRI. Kubo et al. compared radial MRI findings with histological changes of the labrum in ll hips with osteoarthritis using 1.5-T MRJ and found that fibrous separation and mucoid deposition occurred in the labrum with a ''diffuse high signal'' or ''obscure'' pattern. However, to the best of our knowledge, no studies have demonstrated a correlation between MRI fmdings and histological evidence of the severity of degeneration of the labrum. We hypothesized that radially reconstructed images of the acetabular labrum acquired by 3-T MRI can depict degenerative changes of the labrum. In this study, we sought to determine the correlation between MRI and histological findings of the